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authorKartik Agaram <vc@akkartik.com>2019-07-27 16:01:55 -0700
committerKartik Agaram <vc@akkartik.com>2019-07-27 17:47:59 -0700
commit6e1eeeebfb453fa7c871869c19375ce60fbd7413 (patch)
tree539c4a3fdf1756ae79770d5c4aaf6366f1d1525e /apps
parent8846a7f85cc04b77b2fe8a67b6d317723437b00c (diff)
downloadmu-6e1eeeebfb453fa7c871869c19375ce60fbd7413.tar.gz
5485 - promote SubX to top-level
Diffstat (limited to 'apps')
-rw-r--r--apps/Readme.md2
-rwxr-xr-xapps/assortbin0 -> 34384 bytes
-rw-r--r--apps/assort.subx911
-rwxr-xr-xapps/crenshaw2-1bin0 -> 24788 bytes
-rw-r--r--apps/crenshaw2-1.subx585
-rwxr-xr-xapps/crenshaw2-1bbin0 -> 25347 bytes
-rw-r--r--apps/crenshaw2-1b.subx785
-rwxr-xr-xapps/dquotesbin0 -> 40940 bytes
-rw-r--r--apps/dquotes.subx2757
-rwxr-xr-xapps/factorialbin0 -> 23704 bytes
-rw-r--r--apps/factorial.subx117
-rwxr-xr-xapps/handlebin0 -> 24558 bytes
-rw-r--r--apps/handle.subx412
-rwxr-xr-xapps/hexbin0 -> 36939 bytes
-rw-r--r--apps/hex.subx1515
-rwxr-xr-xapps/packbin0 -> 47070 bytes
-rw-r--r--apps/pack.subx5986
-rw-r--r--apps/subx-common.subx3118
-rwxr-xr-xapps/surveybin0 -> 43605 bytes
-rw-r--r--apps/survey.subx4787
-rwxr-xr-xapps/testsbin0 -> 33196 bytes
-rw-r--r--apps/tests.subx279
22 files changed, 21254 insertions, 0 deletions
diff --git a/apps/Readme.md b/apps/Readme.md
new file mode 100644
index 00000000..b76c5a8b
--- /dev/null
+++ b/apps/Readme.md
@@ -0,0 +1,2 @@
+Larger programs than in the subx/examples/ subdirectory, combining the
+techniques demonstrated there.
diff --git a/apps/assort b/apps/assort
new file mode 100755
index 00000000..70d7aaf3
--- /dev/null
+++ b/apps/assort
Binary files differdiff --git a/apps/assort.subx b/apps/assort.subx
new file mode 100644
index 00000000..801e52d0
--- /dev/null
+++ b/apps/assort.subx
@@ -0,0 +1,911 @@
+# Read a series of segments from stdin and concatenate segments with the same
+# name on stdout.
+#
+# Segments are emitted in order of first encounter.
+#
+# Drop lines that are all comments. They could get misleading after assortment
+# because we don't know if they refer to the line above or the line below.
+#
+# To run (from the subx/ directory):
+#   $ ./subx translate *.subx apps/assort.subx -o apps/assort
+#   $ cat x
+#   == code
+#   abc
+#   == code
+#   def
+#   $ cat x  |./subx run apps/assort
+#   == code
+#   abc
+#   def
+
+== code
+#   instruction                     effective address                                                   register    displacement    immediate
+# . op          subop               mod             rm32          base        index         scale       r32
+# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
+
+Entry:
+    # initialize heap
+    # . Heap = new-segment(Heap-size)
+    # . . push args
+    68/push  Heap/imm32
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Heap-size/disp32                  # push *Heap-size
+    # . . call
+    e8/call  new-segment/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+
+    # run tests if necessary, convert stdin if not
+    # . prolog
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # - if argc > 1 and argv[1] == "test", then return run_tests()
+    # . argc > 1
+    81          7/subop/compare     1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0/disp8         1/imm32           # compare *EBP
+    7e/jump-if-lesser-or-equal  $run-main/disp8
+    # . argv[1] == "test"
+    # . . push args
+    68/push  "test"/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  kernel-string-equal?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . check result
+    3d/compare-EAX-and  1/imm32
+    75/jump-if-not-equal  $run-main/disp8
+    # . run-tests()
+    e8/call  run-tests/disp32
+    8b/copy                         0/mod/indirect  5/rm32/.disp32            .             .           3/r32/EBX   Num-test-failures/disp32          # copy *Num-test-failures to EBX
+    eb/jump  $main:end/disp8
+$run-main:
+    # - otherwise convert stdin
+    # var ed/EAX : exit-descriptor
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # subtract from ESP
+    89/copy                         3/mod/direct    0/rm32/EAX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EAX
+    # configure ed to really exit()
+    # . ed->target = 0
+    c7          0/subop/copy        0/mod/direct    0/rm32/EAX    .           .             .           .           .               0/imm32           # copy to *EAX
+    # return convert(Stdin, 1/stdout, 2/stderr, ed)
+    # . . push args
+    50/push-EAX/ed
+    68/push  Stderr/imm32
+    68/push  Stdout/imm32
+    68/push  Stdin/imm32
+    # . . call
+    e8/call  convert/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
+    # . syscall(exit, 0)
+    bb/copy-to-EBX  0/imm32
+$main:end:
+    b8/copy-to-EAX  1/imm32/exit
+    cd/syscall  0x80/imm8
+
+# data structure:
+#   table: (address stream {string, (address stream byte)})     (8 bytes per row)
+# inefficient; uses sequential search for looking up segments by name
+
+convert:  # in : (address buffered-file), out : (address buffered-file) -> <void>
+    # pseudocode:
+    #   var table : (address stream) = new-stream(10 rows, 8 bytes each)
+    #   read-segments(in, table)
+    #   write-segments(out, table)
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    51/push-ECX
+    # var table/ECX : (address stream byte) = stream(10 * 8)
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x50/imm32        # subtract from ESP
+    68/push  0x50/imm32/length
+    68/push  0/imm32/read
+    68/push  0/imm32/write
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # clear-stream(table)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+$convert:read:
+#?     # print("read\n") {{{
+#?     # . . push args
+#?     68/push  "read\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # read-segments(in, table)
+    # . . push args
+    51/push-ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  read-segments/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+$convert:write:
+#?     # print("write\n") {{{
+#?     # . . push args
+#?     68/push  "write\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # write-segments(out, table)
+    # . . push args
+    51/push-ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write-segments/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+$convert:end:
+    # . reclaim locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x5c/imm32        # add to ESP
+    # . restore registers
+    59/pop-to-ECX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-input-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-input-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input (meta comments in parens)
+    #   # comment 1
+    #     # comment 2 indented
+    #   == code 0x09000000  (new segment)
+    #   # comment 3 inside a segment
+    #   1
+    #                         (empty line)
+    #   2 3 # comment 4 inline with other contents
+    #   == data 0x0a000000  (new segment)
+    #   4 5/imm32
+    #   == code  (existing segment but non-contiguous with previous iteration)
+    #   6 7
+    #   8 9  (multiple lines)
+    #   == code  (existing segment contiguous with previous iteration)
+    #   10 11
+    # . write(_test-input-stream, "# comment 1\n")
+    # . . push args
+    68/push  "# comment 1\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "  # comment 2 indented\n")
+    # . . push args
+    68/push  "  # comment 2 indented\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "== code 0x09000000\n")
+    # . . push args
+    68/push  "== code 0x09000000\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "# comment 3 inside a segment\n")
+    # . . push args
+    68/push  "# comment 3 inside a segment\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "1\n")
+    # . . push args
+    68/push  "1\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "\n")  # empty line
+    # . . push args
+    68/push  "\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "2 3 # comment 4 inline with other contents\n")
+    # . . push args
+    68/push  "2 3 # comment 4 inline with other contents\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "== data 0x0a000000\n")
+    # . . push args
+    68/push  "== data 0x0a000000\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "4 5/imm32\n")
+    # . . push args
+    68/push  "4 5/imm32\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "== code\n")
+    # . . push args
+    68/push  "== code\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "6 7\n")
+    # . . push args
+    68/push  "6 7\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "8 9\n")
+    # . . push args
+    68/push  "8 9\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "== code\n")
+    # . . push args
+    68/push  "== code\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "10 11\n")
+    # . . push args
+    68/push  "10 11\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert(_test-input-buffered-file, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-buffered-file/imm32
+    # . . call
+    e8/call  convert/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check output
+    #   == code 0x09000000
+    #   1
+    #   2 3 # comment 4 inline with other contents
+    #   6 7
+    #   8 9
+    #   10 11
+    #   == data 0x0a000000
+    #   4 5/imm32
+#?     # dump output {{{
+#?     # . write(2/stderr, "result: ^")
+#?     # . . push args
+#?     68/push  "result: ^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . rewind-stream(_test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     # . . call
+#?     e8/call  rewind-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # }}}
+    # . check-next-stream-line-equal(_test-output-stream, "== code 0x09000000", msg)
+    # . . push args
+    68/push  "F - test-convert/0"/imm32
+    68/push  "== code 0x09000000"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "1", msg)
+    # . . push args
+    68/push  "F - test-convert/1"/imm32
+    68/push  "1"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "2 3 # comment 4 inline with other contents", msg)
+    # . . push args
+    68/push  "F - test-convert/2"/imm32
+    68/push  "2 3 # comment 4 inline with other contents"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "6 7", msg)
+    # . . push args
+    68/push  "F - test-convert/3"/imm32
+    68/push  "6 7"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "8 9", msg)
+    # . . push args
+    68/push  "F - test-convert/4"/imm32
+    68/push  "8 9"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "10 11", msg)
+    # . . push args
+    68/push  "F - test-convert/5"/imm32
+    68/push  "10 11"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "== data 0x0a000000", msg)
+    # . . push args
+    68/push  "F - test-convert/6"/imm32
+    68/push  "== data 0x0a000000"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "4 5/imm32", msg)
+    # . . push args
+    68/push  "F - test-convert/7"/imm32
+    68/push  "4 5/imm32"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+# beware: leaks memory (one name per segment read)
+read-segments:  # in : (address buffered-file), table : (address stream {string, (address stream byte)})
+    # pseudocode:
+    #   var curr-segment = null
+    #   var line = new-stream(512, 1)
+    #   while true
+    #     clear-stream(line)
+    #     read-line-buffered(in, line)
+    #     if (line->write == 0) break             # end of file
+    #     var word-slice = next-word(line)
+    #     if slice-empty?(word-slice)             # whitespace
+    #       continue
+    #     if slice-starts-with?(word-slice, "#")  # comment
+    #       continue
+    #     if slice-equal?(word-slice, "==")
+    #       var segment-name = next-word(line)
+    #       segment-slot = leaky-get-or-insert-slice(table, segment-name, row-size=8)
+    #       curr-segment = *segment-slot
+    #       if curr-segment != 0
+    #         continue
+    #       curr-segment = new-stream(Segment-size)
+    #       *segment-slot = curr-segment
+    #     rewind-stream(line)
+    #     write-stream(curr-segment, line)  # abort if curr-segment overflows
+    #
+    # word-slice and segment-name are both slices with disjoint lifetimes, so
+    # we'll use the same address for them.
+    #
+    # registers:
+    #   line: ECX
+    #   word-slice and segment-name: EDX
+    #   segment-name and curr-segment: EBX
+    #   word-slice->start: ESI
+    #   temporary: EAX
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+    51/push-ECX
+    52/push-EDX
+    53/push-EBX
+    56/push-ESI
+    # var line/ECX : (address stream byte) = stream(512)
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x200/imm32       # subtract from ESP
+    68/push  0x200/imm32/length
+    68/push  0/imm32/read
+    68/push  0/imm32/write
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # var word-slice/EDX = {0, 0}
+    68/push  0/imm32/end
+    68/push  0/imm32/start
+    89/copy                         3/mod/direct    2/rm32/EDX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EDX
+$read-segments:loop:
+    # clear-stream(line)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # read-line-buffered(in, line)
+    # . . push args
+    51/push-ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  read-line-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+$read-segments:check0:
+    # if (line->write == 0) break
+    81          7/subop/compare     0/mod/indirect  1/rm32/ECX    .           .             .           .           .               0/imm32           # compare *ECX
+    0f 84/jump-if-equal  $read-segments:break/disp32
+#?     # dump line {{{
+#?     # . write(2/stderr, "LL: ")
+#?     # . . push args
+#?     68/push  "LL: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, line)
+#?     # . . push args
+#?     51/push-ECX
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . rewind-stream(line)
+#?     # . . push args
+#?     51/push-ECX
+#?     # . . call
+#?     e8/call  rewind-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # next-word(line, word-slice)
+    # . . push args
+    52/push-EDX
+    51/push-ECX
+    # . . call
+    e8/call  next-word/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+$read-segments:check1:
+#?     # print("check1\n") {{{
+#?     # . . push args
+#?     68/push  "check1\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # if (slice-empty?(word-slice)) continue
+    # . EAX = slice-empty?(word-slice)
+    # . . push args
+    52/push-EDX
+    # . . call
+    e8/call  slice-empty?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . if (EAX != 0) continue
+    3d/compare-EAX-and  0/imm32
+    0f 85/jump-if-not-equal  $read-segments:loop/disp32
+$read-segments:check-for-comment:
+#?     # print("check for comment\n") {{{
+#?     # . . push args
+#?     68/push  "check for comment\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # if (slice-starts-with?(word-slice, "#")) continue
+    # . start/ESI = word-slice->start
+    8b/copy                         0/mod/indirect  2/rm32/EDX    .           .             .           6/r32/ESI   .               .                 # copy *ECX to ESI
+    # . c/EAX = *start
+    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
+    8a/copy-byte                    0/mod/indirect  6/rm32/ESI    .           .             .           0/r32/AL    .               .                 # copy byte at *ESI to AL
+    # . if (EAX == '#') continue
+    3d/compare-EAX-and  0x23/imm32/hash
+    0f 84/jump-if-equal  $read-segments:loop/disp32
+$read-segments:check-for-segment-header:
+#?     # print("check for segment header\n") {{{
+#?     # . . push args
+#?     68/push  "check for segment header\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+#?     # dump word-slice {{{
+#?     # . write(2/stderr, "AA: ")
+#?     # . . push args
+#?     68/push  "AA: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . clear-stream(Stderr+4)
+#?     # . . push args
+#?     b8/copy-to-EAX  Stderr/imm32
+#?     05/add-to-EAX  4/imm32
+#?     50/push-EAX
+#?     # . . call
+#?     e8/call  clear-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . write-slice-buffered(Stderr, word-slice)
+#?     # . . push args
+#?     52/push-EDX
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  write-slice-buffered/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . flush(Stderr)
+#?     # . . push args
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  flush/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # if !slice-equal?(word-slice, "==") goto next check
+    # . EAX = slice-equal?(word-slice, "==")
+    # . . push args
+    68/push  "=="/imm32
+    52/push-EDX
+    # . . call
+    e8/call  slice-equal?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX == 0) goto check3
+    3d/compare-EAX-and  0/imm32
+    0f 84/jump-if-equal  $read-segments:regular-line/disp32
+    # segment-name = next-word(line)
+    # . . push args
+    52/push-EDX
+    51/push-ECX
+    # . . call
+    e8/call  next-word/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # dump segment name {{{
+#?     # . write(2/stderr, "AA: ")
+#?     # . . push args
+#?     68/push  "AA: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . clear-stream(Stderr+4)
+#?     # . . push args
+#?     b8/copy-to-EAX  Stderr/imm32
+#?     05/add-to-EAX  4/imm32
+#?     50/push-EAX
+#?     # . . call
+#?     e8/call  clear-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . write-slice-buffered(Stderr, word-slice)
+#?     # . . push args
+#?     52/push-EDX
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  write-slice-buffered/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . flush(Stderr)
+#?     # . . push args
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  flush/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # segment-slot/EAX = leaky-get-or-insert-slice(table, segment-name, row-size=8)
+    # . . push args
+    68/push  8/imm32/row-size
+    52/push-EDX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  leaky-get-or-insert-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # curr-segment = *segment-slot
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           3/r32/EBX   .               .                 # copy *EAX to EBX
+    # if (curr-segment != 0) continue
+    81          7/subop/compare     3/mod/direct    3/rm32/EBX    .           .             .           .           .               0/imm32           # compare EBX
+    0f 85/jump-if-not-equal  $read-segments:loop/disp32
+    # curr-segment = new-stream(Heap, Segment-size, 1)
+    # . save segment-slot
+    50/push-EAX
+    # . EAX = new-stream(Heap, Segment-size, 1)
+    # . . push args
+    68/push  1/imm32
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Segment-size/disp32               # push *Segment-size
+    68/push  Heap/imm32
+    # . . call
+    e8/call  new-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . curr-segment = EAX
+    89/copy                         3/mod/direct    3/rm32/EBX    .           .             .           0/r32/EAX   .               .                 # copy EAX to EBX
+    # . restore segment-slot
+    58/pop-to-EAX
+    # *segment-slot = curr-segment
+    89/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           3/r32/EBX   .               .                 # copy EBX to *EAX
+    # fall through
+$read-segments:regular-line:
+#?     # print("regular line\n") {{{
+#?     # . . push args
+#?     68/push  "regular line\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+#?     # dump line {{{
+#?     # . write(2/stderr, "regular line: ")
+#?     # . . push args
+#?     68/push  "regular line: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . rewind-stream(line)
+#?     # . . push args
+#?     51/push-ECX
+#?     # . . call
+#?     e8/call  rewind-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . write-stream(2/stderr, line)
+#?     # . . push args
+#?     51/push-ECX
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # rewind-stream(line)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  rewind-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # print("write stream\n") {{{
+#?     # . . push args
+#?     68/push  "write stream\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # write-stream(curr-segment, line)
+    # . . push args
+    51/push-ECX
+    53/push-EBX
+    # . . call
+    e8/call  write-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # loop
+#?     # print("loop\n") {{{
+#?     # . . push args
+#?     68/push  "loop\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    e9/jump  $read-segments:loop/disp32
+$read-segments:break:
+$read-segments:end:
+    # . reclaim locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x214/imm32       # add to ESP
+    # . restore registers
+    5e/pop-to-ESI
+    5b/pop-to-EBX
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+write-segments:  # out : (address buffered-file), table : (address stream {string, (address stream byte)})
+    # pseudocode:
+    #   var curr = table->data
+    #   var max = table->data + table->write
+    #   while curr < max
+    #     stream = table[i].stream
+    #     write-stream-data(out, stream)
+    #     curr += 8
+    #   flush(out)
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+    52/push-EDX
+    56/push-ESI
+    # ESI = table
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   0xc/disp8       .                 # copy *(EBP+12) to ESI
+    # write/EDX = table->write
+    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           2/r32/EDX   .               .                 # copy *ESI to EDX
+    # curr/ESI = table->data
+    81          0/subop/add         3/mod/direct    6/rm32/ESI    .           .             .           .           .               0xc/imm32         # add to EAX
+    # max/EDX = curr + write
+    01/add                          3/mod/direct    2/rm32/EDX    .           .             .           6/r32/ESI   .               .                 # add ESI to EDX
+$write-segments:loop:
+    # if (curr >= max) break
+    39/compare                      3/mod/direct    6/rm32/ESI    .           .             .           2/r32/EDX   .               .                 # compare ESI with EDX
+    73/jump-if-greater-or-equal-unsigned  $write-segments:break/disp8
+    # stream/EAX = table[i].stream
+    8b/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           0/r32/EAX   4/disp8         .                 # copy *(ESI+4) to EAX
+    # write-stream-data(out, stream)
+    # . . push args
+    50/push-EAX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  write-stream-data/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+$write-segments:continue:
+    # curr += 8
+    81          0/subop/add         3/mod/direct    6/rm32/ESI    .           .             .           .           .               8/imm32           # add to ESI
+    eb/jump  $write-segments:loop/disp8
+$write-segments:break:
+    # flush(out)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+$write-segments:end:
+    # . restore registers
+    5e/pop-to-ESI
+    5a/pop-to-EDX
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+# . . vim:nowrap:textwidth=0
diff --git a/apps/crenshaw2-1 b/apps/crenshaw2-1
new file mode 100755
index 00000000..47ee601e
--- /dev/null
+++ b/apps/crenshaw2-1
Binary files differdiff --git a/apps/crenshaw2-1.subx b/apps/crenshaw2-1.subx
new file mode 100644
index 00000000..0c3f180b
--- /dev/null
+++ b/apps/crenshaw2-1.subx
@@ -0,0 +1,585 @@
+# Port of https://github.com/akkartik/crenshaw/blob/master/tutor2.1.pas
+# which corresponds to the section "single digits" in https://compilers.iecc.com/crenshaw/tutor2.txt
+# except that we support hex digits.
+#
+# To run (from the subx/ directory):
+#   $ ./subx translate *.subx apps/crenshaw2-1.subx -o apps/crenshaw2-1
+#   $ echo '3'  |./subx run apps/crenshaw2-1
+# Expected output:
+#   # syscall(exit, 3)
+#   bb/copy-to-EBX  3/imm32
+#   b8/copy-to-EAX  1/imm32/exit
+#   cd/syscall  0x80/imm8
+#
+# To run the generated output:
+#   $ echo '3'  |./subx run apps/crenshaw2-1 > z1.subx
+#   $ ./subx translate z1.subx -o z1
+#   $ ./subx run z1
+#   $ echo $?
+#   3
+#
+# Stdin must contain just a single hex digit. Other input will print an error:
+#   $ echo 'xyz'  |./subx run apps/crenshaw2-1
+#   Error: integer expected
+#
+# Names in this file sometimes follow Crenshaw's original rather than my usual
+# naming conventions.
+
+== code
+#   instruction                     effective address                                                   register    displacement    immediate
+# . op          subop               mod             rm32          base        index         scale       r32
+# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
+
+Entry:  # run tests if necessary, call 'compile' if not
+    # initialize heap
+    # . Heap = new-segment(64KB)
+    # . . push args
+    68/push  Heap/imm32
+    68/push  0x10000/imm32/64KB
+    # . . call
+    e8/call  new-segment/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+
+    # . prolog
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # - if argc > 1 and argv[1] == "test", then return run_tests()
+    # . argc > 1
+    81          7/subop/compare     1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0/disp8         1/imm32           # compare *EBP
+    7e/jump-if-lesser-or-equal  $run-main/disp8
+    # . argv[1] == "test"
+    # . . push args
+    68/push  "test"/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  kernel-string-equal?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . check result
+    3d/compare-EAX-and  1/imm32
+    75/jump-if-not-equal  $run-main/disp8
+    # . run-tests()
+    e8/call  run-tests/disp32
+    8b/copy                         0/mod/indirect  5/rm32/.disp32            .             .           3/r32/EBX   Num-test-failures/disp32          # copy *Num-test-failures to EBX
+    eb/jump  $main:end/disp8
+$run-main:
+    # - otherwise read a program from stdin and emit its translation to stdout
+    # var ed/EAX : exit-descriptor
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # subtract from ESP
+    89/copy                         3/mod/direct    0/rm32/EAX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EAX
+    # configure ed to really exit()
+    # . ed->target = 0
+    c7          0/subop/copy        0/mod/direct    0/rm32/EAX    .           .             .           .           .               0/imm32           # copy to *EAX
+    # return compile(Stdin, 1/stdout, 2/stderr, ed)
+    # . . push args
+    50/push-EAX/ed
+    68/push  2/imm32/stderr
+    68/push  1/imm32/stdout
+    68/push  Stdin/imm32
+    # . . call
+    e8/call  compile/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
+    # . syscall(exit, 0)
+    bb/copy-to-EBX  0/imm32
+$main:end:
+    b8/copy-to-EAX  1/imm32/exit
+    cd/syscall  0x80/imm8
+
+# the main entry point
+compile:  # in : (address buffered-file), out : fd or (address stream), err : fd or (address stream), ed : (address exit-descriptor) -> <void>
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+    51/push-ECX
+    # prime the pump
+    # . Look = get-char(in)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8      .                    # push *(EBP+8)
+    # . . call
+    e8/call  get-char/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # var num/ECX : (address stream) on the stack
+    # Numbers can be 32 bits or 8 hex bytes long. One of them will be in 'Look', so we need space for 7 bytes.
+    # Sizing the stream just right buys us overflow-handling for free inside 'get-num'.
+    # Add 12 bytes for 'read', 'write' and 'length' fields, for a total of 19 bytes, or 0x13 in hex.
+    # The stack pointer is no longer aligned, so dump_stack() can be misleading past this point.
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x13/imm32        # subtract from ESP
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # initialize the stream
+    # . num->length = 7
+    c7          0/subop/copy        1/mod/*+disp8   1/rm32/ECX    .           .             .           .           8/disp8         7/imm32           # copy to *(ECX+8)
+    # . clear-stream(num)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # read a digit from 'in' into 'num'
+    # . get-num(in, num, err, ed)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x14/disp8      .                 # push *(EBP+20)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x10/disp8      .                 # push *(EBP+16)
+    51/push-ECX/num
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8      .                    # push *(EBP+8)
+    # . . call
+    e8/call  get-num/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
+    # render 'num' into the following template on 'out':
+    #   bb/copy-to-EBX  _num_
+    #   b8/copy-to-EAX  1/imm32/exit
+    #   cd/syscall  0x80/imm8
+    #
+    # . write(out, "bb/copy-to-EBX  ")
+    # . . push args
+    68/push  "bb/copy-to-EBX  "/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write-stream(out, num)
+    # . . push args
+    51/push-ECX/num
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(out, Newline)
+    # . . push args
+    68/push  Newline/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(out, "b8/copy-to-EAX  1/imm32/exit\n")
+    # . . push args
+    68/push  "b8/copy-to-EAX  1/imm32/exit\n"/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(out, "cd/syscall  0x80/imm8\n")
+    # . . push args
+    68/push  "cd/syscall  0x80/imm8\n"/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+$compile:end:
+    # . restore registers
+    59/pop-to-ECX
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+# Read a single digit into 'out'. Abort if there are none, or if there is no space in 'out'.
+# Input comes from the global variable 'Look', and we leave the next byte from
+# 'in' into it on exit.
+get-num:  # in : (address buffered-file), out : (address stream), err : fd or (address stream), ed : (address exit-descriptor) -> <void>
+    # pseudocode:
+    #   if (!is-digit?(Look)) expected(ed, err, "integer")
+    #   if out->write >= out->length
+    #     write(err, "Error: too many digits in number\n")
+    #     stop(ed, 1)
+    #   out->data[out->write] = LSB(Look)
+    #   ++out->write
+    #   Look = get-char(in)
+    #
+    # registers:
+    #   in: ESI
+    #   out: EDI
+    #   out->write: ECX (cached copy; need to keep in sync)
+    #   out->length: EDX
+    #   temporaries: EAX, EBX
+    # We can't allocate Look to a register because it gets written implicitly in
+    # get-char in each iteration of the loop. (Thereby demonstrating that it's
+    # not the right interface for us. But we'll keep it just to follow Crenshaw.)
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # - if (is-digit?(Look)) expected(ed, err, "integer")
+    # . EAX = is-digit?(Look)
+    # . . push args
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Look/disp32     .                 # push *Look
+    # . . call
+    e8/call  is-digit?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . if (EAX == 0)
+    3d/compare-EAX-and  0/imm32
+    75/jump-if-not-equal  $get-num:main/disp8
+    # . expected(ed, err, "integer")
+    # . . push args
+    68/push  "integer"/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x10/disp8      .                 # push *(EBP+16)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x14/disp8      .                 # push *(EBP+20)
+    # . . call
+    e8/call  expected/disp32  # never returns
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$get-num:main:
+    # - otherwise read a digit
+    # . save registers
+    50/push-EAX
+    51/push-ECX
+    52/push-EDX
+    53/push-EBX
+    56/push-ESI
+    57/push-EDI
+    # read necessary variables to registers
+    # ESI = in
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   8/disp8         .                 # copy *(EBP+8) to ESI
+    # EDI = out
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           7/r32/EDI   0xc/disp8       .                 # copy *(EBP+12) to EDI
+    # ECX = out->write
+    8b/copy                         0/mod/indirect  7/rm32/EDI    .           .             .           1/r32/ECX   .               .                 # copy *EDI to ECX
+    # EDX = out->length
+    8b/copy                         1/mod/*+disp8   7/rm32/EDI    .           .             .           2/r32/EDX   8/disp8         .                 # copy *(EDI+8) to EDX
+    # if (out->write >= out->length) error
+    39/compare                      3/mod/direct    2/rm32/EDX    .           .             .           1/r32/ECX   .               .                 # compare EDX with ECX
+    7d/jump-if-lesser  $get-num:stage2/disp8
+    # . error(ed, err, msg)  # TODO: show full number
+    # . . push args
+    68/push  "get-num: too many digits in number"/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x10/disp8      .                 # push *(EBP+16)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x14/disp8      .                 # push *(EBP+20)
+    # . . call
+    e8/call  error/disp32  # never returns
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$get-num:stage2:
+    # out->data[out->write] = LSB(Look)
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    7/base/EDI  1/index/ECX   .           3/r32/EBX   0xc/disp8       .                 # copy EDI+ECX+12 to EBX
+    8b/copy                         0/mod/indirect  5/rm32/.disp32            .             .           0/r32/EAX   Look/disp32     .                 # copy *Look to EAX
+    88/copy-byte                    0/mod/indirect  3/rm32/EBX    .           .             .           0/r32/AL    .               .                 # copy byte at AL to *EBX
+    # ++out->write
+    41/increment-ECX
+    # Look = get-char(in)
+    # . . push args
+    56/push-ESI
+    # . . call
+    e8/call  get-char/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+$get-num:loop-end:
+    # persist necessary variables from registers
+    89/copy                         0/mod/indirect  7/rm32/EDI    .           .             .           1/r32/ECX   .               .                 # copy ECX to *EDI
+$get-num:end:
+    # . restore registers
+    5f/pop-to-EDI
+    5e/pop-to-ESI
+    5b/pop-to-EBX
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-get-num-reads-single-digit:
+    # - check that get-num returns first character if it's a digit
+    # This test uses exit-descriptors. Use EBP for setting up local variables.
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # clear all streams
+    # . clear-stream(_test-stream)
+    # . . push args
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-error-stream)
+    # . . push args
+    68/push  _test-error-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize 'in'
+    # . write(_test-stream, "3")
+    # . . push args
+    68/push  "3"/imm32
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # initialize exit-descriptor 'ed' for the call to 'get-num' below
+    # . var ed/EAX : exit-descriptor
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # subtract from ESP
+    89/copy                         3/mod/direct    0/rm32/EAX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EAX
+    # . tailor-exit-descriptor(ed, 16)
+    # . . push args
+    68/push  0x10/imm32/nbytes-of-args-for-get-num
+    50/push-EAX/ed
+    # . . call
+    e8/call  tailor-exit-descriptor/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # prime the pump
+    # . get-char(_test-buffered-file)
+    # . . push args
+    68/push  _test-buffered-file/imm32
+    # . . call
+    e8/call  get-char/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # get-num(in, out, err, ed)
+    # . . push args
+    50/push-EAX/ed
+    68/push  _test-error-stream/imm32
+    68/push  _test-output-stream/imm32
+    68/push  _test-buffered-file/imm32
+    # . . call
+    e8/call  get-num/disp32
+    # registers except ESP may be clobbered at this point
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
+    # check-ints-equal(*_test-output-stream->data, '3', msg)
+    # . . push args
+    68/push  "F - test-get-num-reads-single-digit"/imm32
+    68/push  0x33/imm32
+    b8/copy-to-EAX  _test-output-stream/imm32
+    ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           0xc/disp8       .                 # push *(EAX+12)
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . reclaim locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-get-num-aborts-on-non-digit-in-Look:
+    # - check that get-num returns first character if it's a digit
+    # This test uses exit-descriptors. Use EBP for setting up local variables.
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # clear all streams
+    # . clear-stream(_test-stream)
+    # . . push args
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-error-stream)
+    # . . push args
+    68/push  _test-error-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize 'in'
+    # . write(_test-stream, "3")
+    # . . push args
+    68/push  "3"/imm32
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # initialize exit-descriptor 'ed' for the call to 'get-num' below
+    # . var ed/EAX : (address exit-descriptor)
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # subtract from ESP
+    89/copy                         3/mod/direct    0/rm32/EAX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EAX
+    # . tailor-exit-descriptor(ed, 16)
+    # . . push args
+    68/push  0x10/imm32/nbytes-of-args-for-get-num
+    50/push-EAX/ed
+    # . . call
+    e8/call  tailor-exit-descriptor/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # *don't* prime the pump
+    # get-num(in, out, err, ed)
+    # . . push args
+    50/push-EAX/ed
+    68/push  _test-error-stream/imm32
+    68/push  _test-output-stream/imm32
+    68/push  _test-buffered-file/imm32
+    # . . call
+    e8/call  get-num/disp32
+    # registers except ESP may be clobbered at this point
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
+    # check that get-num tried to call exit(1)
+    # . check-ints-equal(ed->value, 2, msg)  # i.e. stop was called with value 1
+    # . . push args
+    68/push  "F - test-get-num-aborts-on-non-digit-in-Look"/imm32
+    68/push  2/imm32
+    # . . push ed->value
+    ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           4/disp8         .                 # push *(EAX+4)
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . reclaim locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    5d/pop-to-EBP
+    c3/return
+
+## helpers
+
+# write(f, "Error: "+s+" expected\n") then stop(ed, 1)
+expected:  # ed : (address exit-descriptor), f : fd or (address stream), s : (address array byte) -> <void>
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # write(f, "Error: ")
+    # . . push args
+    68/push  "Error: "/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # write(f, s)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x10/disp8      .                 # push *(EBP+16)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # write(f, " expected")
+    # . . push args
+    68/push  " expected\n"/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # stop(ed, 1)
+    # . . push args
+    68/push  1/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  stop/disp32
+    # should never get past this point
+$expected:dead-end:
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+# read a byte from 'f', and save it in 'Look'
+get-char:  # f : (address buffered-file) -> <void>
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+    # EAX = read-byte-buffered(f)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  read-byte-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # save EAX to Look
+    89/copy                         0/mod/indirect  5/rm32/.disp32            .             .           0/r32/EAX   Look/disp32     .                 # copy EAX to *Look
+$get-char:end:
+    # . restore registers
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+is-digit?:  # c : int -> EAX : boolean
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # EAX = false
+    b8/copy-to-EAX  0/imm32
+    # if (c < '0') return false
+    81          7/subop/compare     1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         0x30/imm32        # compare *(EBP+8)
+    7c/jump-if-lesser  $is-digit?:end/disp8
+    # if (c > '9') return false
+    81          7/subop/compare     1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         0x39/imm32        # compare *(EBP+8)
+    7f/jump-if-greater  $is-digit?:end/disp8
+    # otherwise return true
+    b8/copy-to-EAX  1/imm32
+$is-digit?:end:
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+== data
+
+Look:  # (char with some extra padding)
+    0/imm32
+
+_test-output-stream:
+    # current write index
+    0/imm32
+    # current read index
+    0/imm32
+    # length
+    8/imm32
+    # data
+    00 00 00 00 00 00 00 00  # 8 bytes
+
+_test-error-stream:
+    # current write index
+    0/imm32
+    # current read index
+    0/imm32
+    # length
+    0x40/imm32
+    # data (4 lines x 16 bytes/line)
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+
+# . . vim:nowrap:textwidth=0
diff --git a/apps/crenshaw2-1b b/apps/crenshaw2-1b
new file mode 100755
index 00000000..fba81a7d
--- /dev/null
+++ b/apps/crenshaw2-1b
Binary files differdiff --git a/apps/crenshaw2-1b.subx b/apps/crenshaw2-1b.subx
new file mode 100644
index 00000000..e1bb6448
--- /dev/null
+++ b/apps/crenshaw2-1b.subx
@@ -0,0 +1,785 @@
+# Port of https://github.com/akkartik/crenshaw/blob/master/tutor2.1.pas
+# which corresponds to the section "single digits" in https://compilers.iecc.com/crenshaw/tutor2.txt
+# except that we support hex numbers of multiple digits.
+#
+# To run (from the subx/ directory):
+#   $ ./subx translate *.subx apps/crenshaw2-1b.subx -o apps/crenshaw2-1b
+#   $ echo '1a'  |./subx run apps/crenshaw2-1b
+# Expected output:
+#   # syscall(exit, 1a)
+#   bb/copy-to-EBX  3/imm32
+#   b8/copy-to-EAX  1/imm32/exit
+#   cd/syscall  0x80/imm8
+#
+# To run the generated output:
+#   $ echo '1a'  |./subx run apps/crenshaw2-1b > z1.subx
+#   $ ./subx translate z1.subx -o z1
+#   $ ./subx run z1
+#   $ echo $?
+#   26  # 0x1a in decimal
+#
+# Stdin must contain just a single hex digit. Other input will print an error:
+#   $ echo 'xyz'  |./subx run apps/crenshaw2-1b
+#   Error: integer expected
+#
+# Names in this file sometimes follow Crenshaw's original rather than my usual
+# naming conventions.
+
+== code
+#   instruction                     effective address                                                   register    displacement    immediate
+# . op          subop               mod             rm32          base        index         scale       r32
+# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
+
+Entry:  # run tests if necessary, call 'compile' if not
+    # initialize heap
+    # . Heap = new-segment(64KB)
+    # . . push args
+    68/push  Heap/imm32
+    68/push  0x10000/imm32/64KB
+    # . . call
+    e8/call  new-segment/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+
+    # . prolog
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # - if argc > 1 and argv[1] == "test", then return run_tests()
+    # . argc > 1
+    81          7/subop/compare     1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0/disp8         1/imm32           # compare *EBP
+    7e/jump-if-lesser-or-equal  $run-main/disp8
+    # . argv[1] == "test"
+    # . . push args
+    68/push  "test"/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  kernel-string-equal?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . check result
+    3d/compare-EAX-and  1/imm32
+    75/jump-if-not-equal  $run-main/disp8
+    # . run-tests()
+    e8/call  run-tests/disp32
+    8b/copy                         0/mod/indirect  5/rm32/.disp32            .             .           3/r32/EBX   Num-test-failures/disp32          # copy *Num-test-failures to EBX
+    eb/jump  $main:end/disp8
+$run-main:
+    # - otherwise read a program from stdin and emit its translation to stdout
+    # var ed/EAX : exit-descriptor
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # subtract from ESP
+    89/copy                         3/mod/direct    0/rm32/EAX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EAX
+    # configure ed to really exit()
+    # . ed->target = 0
+    c7          0/subop/copy        0/mod/direct    0/rm32/EAX    .           .             .           .           .               0/imm32           # copy to *EAX
+    # return compile(Stdin, 1/stdout, 2/stderr, ed)
+    # . . push args
+    50/push-EAX/ed
+    68/push  2/imm32/stderr
+    68/push  1/imm32/stdout
+    68/push  Stdin/imm32
+    # . . call
+    e8/call  compile/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
+    # . syscall(exit, 0)
+    bb/copy-to-EBX  0/imm32
+$main:end:
+    b8/copy-to-EAX  1/imm32/exit
+    cd/syscall  0x80/imm8
+
+# the main entry point
+compile:  # in : (address buffered-file), out : fd or (address stream), err : fd or (address stream), ed : (address exit-descriptor) -> <void>
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+    51/push-ECX
+    # prime the pump
+    # . Look = get-char(in)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8      .                    # push *(EBP+8)
+    # . . call
+    e8/call  get-char/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # var num/ECX : (address stream) on the stack
+    # Numbers can be 32 bits or 8 hex bytes long. One of them will be in 'Look', so we need space for 7 bytes.
+    # Sizing the stream just right buys us overflow-handling for free inside 'get-num'.
+    # Add 12 bytes for 'read', 'write' and 'length' fields, for a total of 19 bytes, or 0x13 in hex.
+    # The stack pointer is no longer aligned, so dump_stack() can be misleading past this point.
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x13/imm32        # subtract from ESP
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # initialize the stream
+    # . num->length = 7
+    c7          0/subop/copy        1/mod/*+disp8   1/rm32/ECX    .           .             .           .           8/disp8         7/imm32           # copy to *(ECX+8)
+    # . clear-stream(num)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # read a digit from 'in' into 'num'
+    # . get-num(in, num, err, ed)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x14/disp8      .                 # push *(EBP+20)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x10/disp8      .                 # push *(EBP+16)
+    51/push-ECX/num
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8      .                    # push *(EBP+8)
+    # . . call
+    e8/call  get-num/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
+    # render 'num' into the following template on 'out':
+    #   bb/copy-to-EBX  _num_
+    #   b8/copy-to-EAX  1/imm32/exit
+    #   cd/syscall  0x80/imm8
+    #
+    # . write(out, "bb/copy-to-EBX  ")
+    # . . push args
+    68/push  "bb/copy-to-EBX  "/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write-stream(out, num)
+    # . . push args
+    51/push-ECX/num
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(out, Newline)
+    # . . push args
+    68/push  Newline/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(out, "b8/copy-to-EAX  1/imm32/exit\n")
+    # . . push args
+    68/push  "b8/copy-to-EAX  1/imm32/exit\n"/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(out, "cd/syscall  0x80/imm8\n")
+    # . . push args
+    68/push  "cd/syscall  0x80/imm8\n"/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+$compile:end:
+    # . restore registers
+    59/pop-to-ECX
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+# Read a sequence of digits into 'out'. Abort if there are none, or if there is
+# no space in 'out'.
+# Input comes from the global variable 'Look' (first byte) and the argument
+# 'in' (rest). We leave the next byte from 'in' into 'Look' on exit.
+get-num:  # in : (address buffered-file), out : (address stream), err : fd or (address stream), ed : (address exit-descriptor) -> <void>
+    # pseudocode:
+    #   if (!is-digit?(Look)) expected(ed, err, "integer")
+    #   do
+    #     if out->write >= out->length
+    #       write(err, "Error: too many digits in number\n")
+    #       stop(ed, 1)
+    #     out->data[out->write] = LSB(Look)
+    #     ++out->write
+    #     Look = get-char(in)
+    #   while is-digit?(Look)
+    # This is complicated because I don't want to hard-code the error strategy in
+    # a general helper like write-byte-buffered. Maybe I should just create a
+    # local helper.
+    #
+    # within the loop we'll try to keep things in registers:
+    #   in: ESI
+    #   out: EDI
+    #   out->write: ECX (cached copy; need to keep in sync)
+    #   out->length: EDX
+    #   temporaries: EAX, EBX
+    # We can't allocate Look to a register because it gets written implicitly in
+    # get-char in each iteration of the loop. (Thereby demonstrating that it's
+    # not the right interface for us. But we'll keep it just to follow Crenshaw.)
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # - if (is-digit?(Look)) expected(ed, err, "integer")
+    # . EAX = is-digit?(Look)
+    # . . push args
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Look/disp32     .                 # push *Look
+    # . . call
+    e8/call  is-digit?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . if (EAX == 0)
+    3d/compare-EAX-and  0/imm32
+    75/jump-if-not-equal  $get-num:main/disp8
+    # . expected(ed, err, "integer")
+    # . . push args
+    68/push  "integer"/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x10/disp8      .                 # push *(EBP+16)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x14/disp8      .                 # push *(EBP+20)
+    # . . call
+    e8/call  expected/disp32  # never returns
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$get-num:main:
+    # - otherwise read a digit
+    # . save registers
+    50/push-EAX
+    51/push-ECX
+    52/push-EDX
+    53/push-EBX
+    56/push-ESI
+    57/push-EDI
+    # read necessary variables to registers
+    # ESI = in
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   8/disp8         .                 # copy *(EBP+8) to ESI
+    # EDI = out
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           7/r32/EDI   0xc/disp8       .                 # copy *(EBP+12) to EDI
+    # ECX = out->write
+    8b/copy                         0/mod/indirect  7/rm32/EDI    .           .             .           1/r32/ECX   .               .                 # copy *EDI to ECX
+    # EDX = out->length
+    8b/copy                         1/mod/*+disp8   7/rm32/EDI    .           .             .           2/r32/EDX   8/disp8         .                 # copy *(EDI+8) to EDX
+$get-num:loop:
+    # if (out->write >= out->length) error
+    39/compare                      3/mod/direct    2/rm32/EDX    .           .             .           1/r32/ECX   .               .                 # compare EDX with ECX
+    7d/jump-if-lesser  $get-num:loop-stage2/disp8
+    # . error(ed, err, msg)  # TODO: show full number
+    # . . push args
+    68/push  "get-num: too many digits in number"/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x10/disp8      .                 # push *(EBP+16)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x14/disp8      .                 # push *(EBP+20)
+    # . . call
+    e8/call  error/disp32  # never returns
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$get-num:loop-stage2:
+    # out->data[out->write] = LSB(Look)
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    7/base/EDI  1/index/ECX   .           3/r32/EBX   0xc/disp8       .                 # copy EDI+ECX+12 to EBX
+    8b/copy                         0/mod/indirect  5/rm32/.disp32            .             .           0/r32/EAX   Look/disp32     .                 # copy *Look to EAX
+    88/copy-byte                    0/mod/indirect  3/rm32/EBX    .           .             .           0/r32/AL    .               .                 # copy byte at AL to *EBX
+    # ++out->write
+    41/increment-ECX
+    # Look = get-char(in)
+    # . . push args
+    56/push-ESI
+    # . . call
+    e8/call  get-char/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # if (is-digit?(Look)) loop
+    # . EAX = is-digit?(Look)
+    # . . push args
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Look/disp32     .                 # push *Look
+    # . . call
+    e8/call  is-digit?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . if (EAX != 0) loop
+    3d/compare-EAX-and  0/imm32
+    0f 85/jump-if-not-equal  $get-num:loop/disp32
+$get-num:loop-end:
+    # persist necessary variables from registers
+    89/copy                         0/mod/indirect  7/rm32/EDI    .           .             .           1/r32/ECX   .               .                 # copy ECX to *EDI
+$get-num:end:
+    # . restore registers
+    5f/pop-to-EDI
+    5e/pop-to-ESI
+    5b/pop-to-EBX
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-get-num-reads-single-digit:
+    # - check that get-num returns first character if it's a digit
+    # This test uses exit-descriptors. Use EBP for setting up local variables.
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # clear all streams
+    # . clear-stream(_test-stream)
+    # . . push args
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-error-stream)
+    # . . push args
+    68/push  _test-error-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize 'in'
+    # . write(_test-stream, "3")
+    # . . push args
+    68/push  "3"/imm32
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # initialize exit-descriptor 'ed' for the call to 'get-num' below
+    # . var ed/EAX : exit-descriptor
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # subtract from ESP
+    89/copy                         3/mod/direct    0/rm32/EAX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EAX
+    # . tailor-exit-descriptor(ed, 16)
+    # . . push args
+    68/push  0x10/imm32/nbytes-of-args-for-get-num
+    50/push-EAX/ed
+    # . . call
+    e8/call  tailor-exit-descriptor/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # prime the pump
+    # . get-char(_test-buffered-file)
+    # . . push args
+    68/push  _test-buffered-file/imm32
+    # . . call
+    e8/call  get-char/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # get-num(in, out, err, ed)
+    # . . push args
+    50/push-EAX/ed
+    68/push  _test-error-stream/imm32
+    68/push  _test-output-stream/imm32
+    68/push  _test-buffered-file/imm32
+    # . . call
+    e8/call  get-num/disp32
+    # registers except ESP may be clobbered at this point
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
+    # check-ints-equal(*_test-output-stream->data, '3', msg)
+    # . . push args
+    68/push  "F - test-get-num-reads-single-digit"/imm32
+    68/push  0x33/imm32
+    b8/copy-to-EAX  _test-output-stream/imm32
+    ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           0xc/disp8       .                 # push *(EAX+12)
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . reclaim locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-get-num-aborts-on-non-digit-in-Look:
+    # - check that get-num returns first character if it's a digit
+    # This test uses exit-descriptors. Use EBP for setting up local variables.
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # clear all streams
+    # . clear-stream(_test-stream)
+    # . . push args
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-error-stream)
+    # . . push args
+    68/push  _test-error-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize 'in'
+    # . write(_test-stream, "3")
+    # . . push args
+    68/push  "3"/imm32
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # initialize exit-descriptor 'ed' for the call to 'get-num' below
+    # . var ed/EAX : (address exit-descriptor)
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # subtract from ESP
+    89/copy                         3/mod/direct    0/rm32/EAX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EAX
+    # . tailor-exit-descriptor(ed, 16)
+    # . . push args
+    68/push  0x10/imm32/nbytes-of-args-for-get-num
+    50/push-EAX/ed
+    # . . call
+    e8/call  tailor-exit-descriptor/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # *don't* prime the pump
+    # get-num(in, out, err, ed)
+    # . . push args
+    50/push-EAX/ed
+    68/push  _test-error-stream/imm32
+    68/push  _test-output-stream/imm32
+    68/push  _test-buffered-file/imm32
+    # . . call
+    e8/call  get-num/disp32
+    # registers except ESP may be clobbered at this point
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
+    # check that get-num tried to call exit(1)
+    # . check-ints-equal(ed->value, 2, msg)  # i.e. stop was called with value 1
+    # . . push args
+    68/push  "F - test-get-num-aborts-on-non-digit-in-Look"/imm32
+    68/push  2/imm32
+    # . . push ed->value
+    ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           4/disp8         .                 # push *(EAX+4)
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . reclaim locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-get-num-reads-multiple-digits:
+    # - check that get-num returns all initial digits until it encounters a non-digit
+    # This test uses exit-descriptors. Use EBP for setting up local variables.
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # clear all streams
+    # . clear-stream(_test-stream)
+    # . . push args
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-error-stream)
+    # . . push args
+    68/push  _test-error-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize 'in'
+    # . write(_test-stream, "3456 x")
+    # . . push args
+    68/push  "3456"/imm32
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # initialize exit-descriptor 'ed' for the call to 'get-num' below
+    # . var ed/EAX : (address exit-descriptor)
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # subtract from ESP
+    89/copy                         3/mod/direct    0/rm32/EAX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EAX
+    # . tailor-exit-descriptor(ed, 16)
+    # . . push args
+    68/push  0x10/imm32/nbytes-of-args-for-get-num
+    50/push-EAX/ed
+    # . . call
+    e8/call  tailor-exit-descriptor/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # prime the pump
+    # . get-char(_test-buffered-file)
+    # . . push args
+    68/push  _test-buffered-file/imm32
+    # . . call
+    e8/call  get-char/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # get-num(in, out, err, ed)
+    # . . push args
+    50/push-EAX/ed
+    68/push  _test-error-stream/imm32
+    68/push  _test-output-stream/imm32
+    68/push  _test-buffered-file/imm32
+    # . . call
+    e8/call  get-num/disp32
+    # registers except ESP may be clobbered at this point
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
+    # check-ints-equal(*_test-output-stream->data, '3456', msg)
+    # . . push args
+    68/push  "F - test-get-num-reads-multiple-digits"/imm32
+    68/push  0x36353433/imm32
+    b8/copy-to-EAX  _test-output-stream/imm32
+    ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           0xc/disp8       .                 # push *(EAX+12)
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . reclaim locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-get-num-reads-multiple-digits-followed-by-nondigit:
+    # - check that get-num returns all initial digits until it encounters a non-digit
+    # This test uses exit-descriptors. Use EBP for setting up local variables.
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # clear all streams
+    # . clear-stream(_test-stream)
+    # . . push args
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-error-stream)
+    # . . push args
+    68/push  _test-error-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize 'in'
+    # . write(_test-stream, "3456 x")
+    # . . push args
+    68/push  "3456 x"/imm32
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # initialize exit-descriptor 'ed' for the call to 'get-num' below
+    # . var ed/EAX : (address exit-descriptor)
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # subtract from ESP
+    89/copy                         3/mod/direct    0/rm32/EAX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EAX
+    # . tailor-exit-descriptor(ed, 16)
+    # . . push args
+    68/push  0x10/imm32/nbytes-of-args-for-get-num
+    50/push-EAX/ed
+    # . . call
+    e8/call  tailor-exit-descriptor/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # prime the pump
+    # . get-char(_test-buffered-file)
+    # . . push args
+    68/push  _test-buffered-file/imm32
+    # . . call
+    e8/call  get-char/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # get-num(in, out, err, ed)
+    # . . push args
+    50/push-EAX/ed
+    68/push  _test-error-stream/imm32
+    68/push  _test-output-stream/imm32
+    68/push  _test-buffered-file/imm32
+    # . . call
+    e8/call  get-num/disp32
+    # registers except ESP may be clobbered at this point
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
+    # check-ints-equal(*_test-output-stream->data, '3456', msg)
+    # . . push args
+    68/push  "F - test-get-num-reads-multiple-digits-followed-by-nondigit"/imm32
+    68/push  0x36353433/imm32
+    b8/copy-to-EAX  _test-output-stream/imm32
+    ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           0xc/disp8       .                 # push *(EAX+12)
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . reclaim locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    5d/pop-to-EBP
+    c3/return
+
+## helpers
+
+# write(f, "Error: "+s+" expected\n") then stop(ed, 1)
+expected:  # ed : (address exit-descriptor), f : fd or (address stream), s : (address array byte) -> <void>
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # write(f, "Error: ")
+    # . . push args
+    68/push  "Error: "/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # write(f, s)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x10/disp8      .                 # push *(EBP+16)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # write(f, " expected\n")
+    # . . push args
+    68/push  " expected\n"/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # stop(ed, 1)
+    # . . push args
+    68/push  1/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  stop/disp32
+    # should never get past this point
+$expected:dead-end:
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+# read a byte from 'f', and save it in 'Look'
+get-char:  # f : (address buffered-file) -> <void>
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+    # EAX = read-byte-buffered(f)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  read-byte-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # save EAX to Look
+    89/copy                         0/mod/indirect  5/rm32/.disp32            .             .           0/r32/EAX   Look/disp32     .                 # copy EAX to *Look
+$get-char:end:
+    # . restore registers
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+is-digit?:  # c : int -> EAX : boolean
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # EAX = false
+    b8/copy-to-EAX  0/imm32
+    # if (c < '0') return false
+    81          7/subop/compare     1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         0x30/imm32        # compare *(EBP+8)
+    7c/jump-if-lesser  $is-digit?:end/disp8
+    # if (c > '9') return false
+    81          7/subop/compare     1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         0x39/imm32        # compare *(EBP+8)
+    7f/jump-if-greater  $is-digit?:end/disp8
+    # otherwise return true
+    b8/copy-to-EAX  1/imm32
+$is-digit?:end:
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+== data
+
+Look:  # (char with some extra padding)
+    0/imm32
+
+_test-output-stream:
+    # current write index
+    0/imm32
+    # current read index
+    0/imm32
+    # length
+    8/imm32
+    # data
+    00 00 00 00 00 00 00 00  # 8 bytes
+
+_test-error-stream:
+    # current write index
+    0/imm32
+    # current read index
+    0/imm32
+    # length
+    0x40/imm32
+    # data (4 lines x 16 bytes/line)
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+
+# . . vim:nowrap:textwidth=0
diff --git a/apps/dquotes b/apps/dquotes
new file mode 100755
index 00000000..b7a4adfe
--- /dev/null
+++ b/apps/dquotes
Binary files differdiff --git a/apps/dquotes.subx b/apps/dquotes.subx
new file mode 100644
index 00000000..6848ad19
--- /dev/null
+++ b/apps/dquotes.subx
@@ -0,0 +1,2757 @@
+# Translate literal strings within double quotes.
+# Replace them with references to new variables in the data segment.
+#
+# To run (from the subx/ directory):
+#   $ ./subx translate *.subx apps/dquotes.subx -o apps/dquotes
+#   $ cat x
+#   == code
+#   ab "cd ef"/imm32
+#   $ cat x  |./subx run apps/dquotes
+#   == code
+#   ab __string1/imm32
+#   == data
+#   __string1:
+#     5/imm32
+#     0x63/c 0x64/d 0x20/  0x65/e 0x66/f
+
+== code
+#   instruction                     effective address                                                   register    displacement    immediate
+# . op          subop               mod             rm32          base        index         scale       r32
+# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
+
+Entry:
+    # initialize heap
+    # . Heap = new-segment(Heap-size)
+    # . . push args
+    68/push  Heap/imm32
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Heap-size/disp32                  # push *Heap-size
+    # . . call
+    e8/call  new-segment/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+
+    # run tests if necessary, convert stdin if not
+    # . prolog
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # - if argc > 1 and argv[1] == "test", then return run_tests()
+    # . argc > 1
+    81          7/subop/compare     1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0/disp8         1/imm32           # compare *EBP
+    7e/jump-if-lesser-or-equal  $run-main/disp8
+    # . argv[1] == "test"
+    # . . push args
+    68/push  "test"/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  kernel-string-equal?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . check result
+    3d/compare-EAX-and  1/imm32
+    75/jump-if-not-equal  $run-main/disp8
+    # . run-tests()
+    e8/call  run-tests/disp32
+    8b/copy                         0/mod/indirect  5/rm32/.disp32            .             .           3/r32/EBX   Num-test-failures/disp32          # copy *Num-test-failures to EBX
+    eb/jump  $main:end/disp8
+$run-main:
+    # - otherwise convert stdin
+    # var ed/EAX : exit-descriptor
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # subtract from ESP
+    89/copy                         3/mod/direct    0/rm32/EAX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EAX
+    # configure ed to really exit()
+    # . ed->target = 0
+    c7          0/subop/copy        0/mod/direct    0/rm32/EAX    .           .             .           .           .               0/imm32           # copy to *EAX
+    # return convert(Stdin, 1/stdout, 2/stderr, ed)
+    # . . push args
+    50/push-EAX/ed
+    68/push  Stderr/imm32
+    68/push  Stdout/imm32
+    68/push  Stdin/imm32
+    # . . call
+    e8/call  convert/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
+    # . syscall(exit, 0)
+    bb/copy-to-EBX  0/imm32
+$main:end:
+    b8/copy-to-EAX  1/imm32/exit
+    cd/syscall  0x80/imm8
+
+# conceptual hierarchy within a line:
+#   line = words separated by ' ', maybe followed by comment starting with '#'
+#   word = datum until '/', then 0 or more metadata separated by '/'
+
+convert:  # in : (address buffered-file), out : (address buffered-file) -> <void>
+    # pseudocode:
+    #   var line = new-stream(512, 1)
+    #   var new-data-segment = new-stream(Heap, Segment-size, 1)
+    #   write(new-data-segment, "== data\n")
+    #   while true
+    #     clear-stream(line)
+    #     read-line-buffered(in, line)
+    #     if (line->write == 0) break               # end of file
+    #     while true
+    #       var word-slice = next-word-or-string(line)
+    #       if slice-empty?(word-slice)             # end of line
+    #         break
+    #       if slice-starts-with?(word-slice, "#")  # comment
+    #         continue
+    #       if slice-starts-with?(word-slice, '"')  # string literal <== what we're here for
+    #         process-string-literal(word-slice, out, new-data-segment)
+    #       else
+    #         write-slice-buffered(out, word-slice)
+    #       write(out, " ")
+    #     write(out, "\n\n")
+    #   write-stream-data(out, new-data-segment)
+    #   flush(out)
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+    51/push-ECX
+    52/push-EDX
+    53/push-EBX
+    56/push-ESI
+    57/push-EDI
+    # var line/ECX : (address stream byte) = stream(512)
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x200/imm32       # subtract from ESP
+    68/push  0x200/imm32/length
+    68/push  0/imm32/read
+    68/push  0/imm32/write
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # var word-slice/EDX = {0, 0}
+    68/push  0/imm32/end
+    68/push  0/imm32/start
+    89/copy                         3/mod/direct    2/rm32/EDX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EDX
+    # new-data-segment/EDI = new-stream(Heap, Segment-size, 1)
+    # . EAX = new-stream(Heap, Segment-size, 1)
+    # . . push args
+    68/push  1/imm32
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Segment-size/disp32               # push *Segment-size
+    68/push  Heap/imm32
+    # . . call
+    e8/call  new-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . EDI = EAX
+    89/copy                         3/mod/direct    7/rm32/EDI    .           .             .           0/r32/EAX   .               .                 # copy EAX to EDI
+    # write(new-data-segment, "== data\n")
+    # . . push args
+    68/push  "== data\n"/imm32
+    57/push-EDI
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+$convert:line-loop:
+    # clear-stream(line)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # read-line-buffered(in, line)
+    # . . push args
+    51/push-ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  read-line-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+$convert:check0:
+    # if (line->write == 0) break
+    81          7/subop/compare     0/mod/indirect  1/rm32/ECX    .           .             .           .           .               0/imm32           # compare *ECX
+    0f 84/jump-if-equal  $convert:break/disp32
+$convert:word-loop:
+    # next-word-or-string(line, word-slice)
+    # . . push args
+    52/push-EDX
+    51/push-ECX
+    # . . call
+    e8/call  next-word-or-string/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+$convert:check1:
+    # if (slice-empty?(word-slice)) break
+    # . EAX = slice-empty?(word-slice)
+    # . . push args
+    52/push-EDX
+    # . . call
+    e8/call  slice-empty?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . if (EAX != 0) break
+    3d/compare-EAX-and  0/imm32
+    0f 85/jump-if-not-equal  $convert:next-line/disp32
+$convert:check-for-comment:
+    # if (slice-starts-with?(word-slice, "#")) continue
+    # . start/ESI = word-slice->start
+    8b/copy                         0/mod/indirect  2/rm32/EDX    .           .             .           6/r32/ESI   .               .                 # copy *EDX to ESI
+    # . c/EAX = *start
+    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
+    8a/copy-byte                    0/mod/indirect  6/rm32/ESI    .           .             .           0/r32/AL    .               .                 # copy byte at *ESI to AL
+    # . if (EAX == '#') continue
+    3d/compare-EAX-and  0x23/imm32/hash
+    74/jump-if-equal  $convert:word-loop/disp8
+$convert:check-for-string-literal:
+    3d/compare-EAX-and  0x22/imm32/dquote
+    75/jump-if-not-equal  $convert:regular-word/disp8
+$convert:string-literal:
+    # process-string-literal(word-slice, out, new-data-segment)
+    # . . push args
+    57/push-EDI
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    52/push-EDX
+    # . . call
+    e8/call  process-string-literal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # continue
+    eb/jump  $convert:next-word/disp8
+$convert:regular-word:
+    # write-slice-buffered(out, word-slice)
+    # . . push args
+    52/push-EDX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write-slice-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # fall through
+$convert:next-word:
+    # write-buffered(out, " ")
+    # . . push args
+    68/push  " "/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # loop
+    eb/jump  $convert:word-loop/disp8
+$convert:next-line:
+    # write-buffered(out, "\n")
+    # . . push args
+    68/push  Newline/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # loop
+    e9/jump  $convert:line-loop/disp32
+$convert:break:
+    # write-stream-data(out, new-data-segment)
+    # . . push args
+    57/push-EDI
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write-stream-data/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # flush(out)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+$convert:end:
+    # . reclaim locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x214/imm32       # add to ESP
+    # . restore registers
+    5f/pop-to-EDI
+    5e/pop-to-ESI
+    5b/pop-to-EBX
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+# Write out 'string-literal' in a new format to 'out-segment', assign it a new
+# label, and write the new label out to 'out'.
+process-string-literal:  # string-literal : (address slice), out : (address buffered-file), out-segment : (address stream)
+    # pseudocode:
+    #   print(out-segment, "_string#{Next-string-literal}:\n")
+    #   emit-string-literal-data(out-segment, string-literal)
+    #   print(out, "_string#{Next-string-literal}")
+    #   emit-metadata(out, string-literal)
+    #   ++ *Next-string-literal
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    51/push-ECX
+    # var int32-stream/ECX = stream(10)  # number of decimal digits a 32-bit number can have
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xa/imm32         # subtract from ESP
+    68/push  0xa/imm32/decimal-digits-in-32bit-number
+    68/push  0/imm32/read
+    68/push  0/imm32/write
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # print(out-segment, "_string#{Next-string-literal}:\n")
+    # . write(out-segment, "_string")
+    # . . push args
+    68/push  "_string"/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x10/disp8      .                 # push *(EBP+16)
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . print-int32-decimal(out-segment, *Next-string-literal)
+    # . . push args
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Next-string-literal/disp32        # push *Next-string-literal
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x10/disp8      .                 # push *(EBP+16)
+    # . . call
+    e8/call  print-int32-decimal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(out-segment, ":\n")
+    # . . push args
+    68/push  ":\n"/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x10/disp8      .                 # push *(EBP+16)
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # emit-string-literal-data(out-segment, string-literal)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x8/disp8       .                 # push *(EBP+8)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x10/disp8      .                 # push *(EBP+16)
+    # . . call
+    e8/call  emit-string-literal-data/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # write(out-segment, "\n")
+    # . . push args
+    68/push  Newline/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x10/disp8      .                 # push *(EBP+16)
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # print(out, "_string#{Next-string-literal}")
+    # . write-buffered(out, "_string")
+    # . . push args
+    68/push  "_string"/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . print-int32-decimal(int32-stream, *Next-string-literal)
+    # . . push args
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Next-string-literal/disp32        # push *Next-string-literal
+    51/push-ECX
+    # . . call
+    e8/call  print-int32-decimal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write-stream-data(out, int32-stream)
+    # . . push args
+    51/push-ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write-stream-data/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # emit-metadata(out, string-literal)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  emit-metadata/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # ++ *Next-string-literal
+    ff          0/subop/increment   0/mod/indirect  5/rm32/.disp32            .             .           .           Next-string-literal/disp32        # increment *Num-test-failures
+$process-string-literal:end:
+    # . reclaim locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x16/imm32        # add to ESP
+    # . restore registers
+    59/pop-to-ECX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-is-idempotent-by-default:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-input-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-input-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input (meta comments in parens)
+    #   # comment 1
+    #     # comment 2 indented
+    #   == code 0x1  (new segment)
+    #   # comment 3 inside a segment
+    #   1
+    #                         (empty line)
+    #   2 3 # comment 4 inline with other contents
+    #   == data 0x2  (new segment)
+    #   4 5/imm32
+    # . write(_test-input-stream, "# comment 1\n")
+    # . . push args
+    68/push  "# comment 1\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "  # comment 2 indented\n")
+    # . . push args
+    68/push  "  # comment 2 indented\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "== code 0x1\n")
+    # . . push args
+    68/push  "== code 0x1\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "# comment 3 inside a segment\n")
+    # . . push args
+    68/push  "# comment 3 inside a segment\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "1\n")
+    # . . push args
+    68/push  "1\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "\n")  # empty line
+    # . . push args
+    68/push  "\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "2 3 # comment 4 inline with other contents\n")
+    # . . push args
+    68/push  "2 3 # comment 4 inline with other contents\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "== data 0x2\n")
+    # . . push args
+    68/push  "== data 0x2\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "4 5/imm32\n")
+    # . . push args
+    68/push  "4 5/imm32\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert(_test-input-buffered-file, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-buffered-file/imm32
+    # . . call
+    e8/call  convert/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check output
+    #     (comment dropped for now)
+    #     (comment dropped for now)
+    #   == code 0x1
+    #     (comment dropped for now)
+    #   1
+    #     (comment dropped for now)
+    #   2 3
+    #   == data 0x2
+    #   4 5/imm32
+    # We don't care right now what exactly happens to comments. Trailing spaces are also minor details.
+#?     # dump output {{{
+#?     # . write(2/stderr, "result: ^")
+#?     # . . push args
+#?     68/push  "result: ^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-next-stream-line-equal(_test-output-stream, "", msg)
+    # . . push args
+    68/push  "F - test-convert-is-idempotent-by-default/0"/imm32
+    68/push  ""/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "", msg)
+    # . . push args
+    68/push  "F - test-convert-is-idempotent-by-default/1"/imm32
+    68/push  ""/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "== code 0x1 ", msg)
+    # . . push args
+    68/push  "F - test-convert-is-idempotent-by-default/2"/imm32
+    68/push  "== code 0x1 "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "", msg)
+    # . . push args
+    68/push  "F - test-convert-is-idempotent-by-default/3"/imm32
+    68/push  ""/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "1 ", msg)
+    # . . push args
+    68/push  "F - test-convert-is-idempotent-by-default/4"/imm32
+    68/push  "1 "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "", msg)
+    # . . push args
+    68/push  "F - test-convert-is-idempotent-by-default/5"/imm32
+    68/push  ""/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "2 3 ", msg)
+    # . . push args
+    68/push  "F - test-convert-is-idempotent-by-default/6"/imm32
+    68/push  "2 3 "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "== data 0x2 ", msg)
+    # . . push args
+    68/push  "F - test-convert-is-idempotent-by-default/7"/imm32
+    68/push  "== data 0x2 "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "4 5/imm32 ", msg)
+    # . . push args
+    68/push  "F - test-convert-is-idempotent-by-default/8"/imm32
+    68/push  "4 5/imm32 "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-processes-string-literals:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-input-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-input-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input (meta comments in parens)
+    #   == code  (new segment)
+    #   1 "a"/x
+    #   2 "bc"/y
+    68/push  "== code 0x1\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "1 \"a\"/x\n")
+    # . . push args
+    68/push  "1 \"a\"/x\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "2 \"bc\"/y\n")
+    # . . push args
+    68/push  "2 \"bc\"/y\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert(_test-input-buffered-file, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-buffered-file/imm32
+    # . . call
+    e8/call  convert/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check output
+    #   == code 0x1
+    #   1 _string1/x
+    #   2 _string2/y
+    #   == data
+    #   _string1:
+    #   1/imm32 61/a
+    #   _string2:
+    #   2/imm32 62/b 63/c
+    # We don't care right now what exactly happens to comments. Trailing spaces are also minor details.
+    #
+    # Open question: how to make this check more robust.
+    # We don't actually care what the auto-generated string variables are
+    # called. We just want to make sure instructions using string literals
+    # switch to a string variable with the right value.
+    # (Modifying string literals completely off the radar for now.)
+#?     # dump output {{{
+#?     # . write(2/stderr, "result: ^")
+#?     # . . push args
+#?     68/push  "result: ^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . rewind-stream(_test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     # . . call
+#?     e8/call  rewind-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # }}}
+    # . check-next-stream-line-equal(_test-output-stream, "== code 0x1 ", msg)
+    # . . push args
+    68/push  "F - test-convert-processes-string-literals/0"/imm32
+    68/push  "== code 0x1 "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "1 _string1/x ", msg)
+    # . . push args
+    68/push  "F - test-convert-processes-string-literals/1"/imm32
+    68/push  "1 _string1/x "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "2 _string2/y ", msg)
+    # . . push args
+    68/push  "F - test-convert-processes-string-literals/2"/imm32
+    68/push  "2 _string2/y "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "== data", msg)
+    # . . push args
+    68/push  "F - test-convert-processes-string-literals/3"/imm32
+    68/push  "== data"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "_string1: ", msg)
+    # . . push args
+    68/push  "F - test-convert-processes-string-literals/4"/imm32
+    68/push  "_string1:"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "1/imm32 61/a ", msg)
+    # . . push args
+    68/push  "F - test-convert-processes-string-literals/5"/imm32
+    68/push  "0x00000001/imm32 61/a "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "_string2: ", msg)
+    # . . push args
+    68/push  "F - test-convert-processes-string-literals/6"/imm32
+    68/push  "_string2:"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "2/imm32 62/b 63/c ", msg)
+    # . . push args
+    68/push  "F - test-convert-processes-string-literals/7"/imm32
+    68/push  "0x00000002/imm32 62/b 63/c "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+# generate the data segment contents byte by byte for a given slice
+emit-string-literal-data:  # out : (address stream), word : (address slice)
+    # pseudocode
+    #   len = string-length-at-start-of-slice(word->start, word->end)
+    #   print(out, "#{len}/imm32 ")
+    #   curr = word->start
+    #   ++curr  # skip '"'
+    #   while true
+    #     if (curr >= word->end) break
+    #     c = *curr
+    #     if (c == '"') break
+    #     if (c == '\') {
+    #       ++curr
+    #       c = *curr
+    #       if (c == 'n')
+    #         c = newline
+    #     }
+    #     append-byte-hex(out, c)
+    #     if c is alphanumeric:
+    #       write(out, "/")
+    #       append-byte(out, c)
+    #     write(out, " ")
+    #     ++curr
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+    51/push-ECX
+    52/push-EDX
+    56/push-ESI
+    # ESI = word
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   0xc/disp8       .                 # copy *(EBP+12) to ESI
+    # curr/EDX = word->start
+    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           2/r32/EDX   .               .                 # copy *ESI to EDX
+    # max/ESI = word->end
+    8b/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           6/r32/ESI   4/disp8         .                 # copy *(ESI+4) to ESI
+$emit-string-literal-data:emit-length:
+    # len/EAX = string-length-at-start-of-slice(word->start, word->end)
+    # . . push args
+    56/push-ESI
+    52/push-EDX
+    # . . call
+    e8/call  string-length-at-start-of-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # print(out, "#{len}/imm32 ")
+    # . print-int32(out, len)
+    # . . push args
+    50/push-EAX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  print-int32/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(out, "/imm32 ")
+    # . . push args
+    68/push  "/imm32 "/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+$emit-string-literal-data:loop-init:
+    # ++curr  # skip initial '"'
+    42/increment-EDX
+    # c/ECX = 0
+    31/xor                          3/mod/direct    1/rm32/ECX    .           .             .           1/r32/ECX   .               .                 # clear ECX
+$emit-string-literal-data:loop:
+    # if (curr >= max) break
+    39/compare                      3/mod/direct    2/rm32/EDX    .           .             .           6/r32/ESI   .               .                 # compare EDX with ESI
+    0f 83/jump-if-greater-or-equal-unsigned  $emit-string-literal-data:end/disp32
+    # CL = *curr
+    8a/copy-byte                    0/mod/indirect  2/rm32/EDX    .           .             .           1/r32/CL    .               .                 # copy byte at *EDX to CL
+    # if (c == '"') break
+    81          7/subop/compare     3/mod/direct    1/rm32/ECX    .           .             .           .           .               0x22/imm32/dquote # compare ECX
+    74/jump-if-equal  $emit-string-literal-data:end/disp8
+    # if (c != '\') goto emit
+    81          7/subop/compare     3/mod/direct    1/rm32/ECX    .           .             .           .           .               0x5c/imm32/backslash  # compare ECX
+    75/jump-if-not-equal  $emit-string-literal-data:emit/disp8
+    # ++curr
+    42/increment-EDX
+    # if (curr >= max) break
+    39/compare                      3/mod/direct    2/rm32/EDX    .           .             .           6/r32/ESI   .               .                 # compare EDX with ESI
+    73/jump-if-greater-or-equal-unsigned  $emit-string-literal-data:end/disp8
+    # c = *curr
+    8a/copy-byte                    0/mod/indirect  2/rm32/EDX    .           .             .           1/r32/CL    .               .                 # copy byte at *EDX to CL
+    # if (c == 'n') c = newline
+    81          7/subop/compare     3/mod/direct    1/rm32/ECX    .           .             .           .           .               0x6e/imm32/n      # compare ECX
+    75/jump-if-not-equal  $emit-string-literal-data:emit/disp8
+    b9/copy-to-ECX  0x0a/imm32/newline
+$emit-string-literal-data:emit:
+    # append-byte-hex(out, CL)
+    # . . push args
+    51/push-ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  append-byte-hex/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # if (is-alphanumeric?(*curr)) print(out, "/#{*curr}")
+    # . EAX = is-alphanumeric?(CL)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  is-alphanumeric?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . if (EAX == 0) goto char-done
+    3d/compare-EAX-and  0/imm32
+    74/jump-if-equal  $emit-string-literal-data:char-done/disp8
+    # . write(out, "/")
+    # . . push args
+    68/push  Slash/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . append-byte(out, *curr)
+    # . . push args
+    51/push-ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  append-byte/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+$emit-string-literal-data:char-done:
+    # write(out, " ")
+    # . . push args
+    68/push  Space/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # ++curr
+    42/increment-EDX
+    e9/jump $emit-string-literal-data:loop/disp32
+$emit-string-literal-data:end:
+    # . restore registers
+    5e/pop-to-ESI
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+is-alphanumeric?:  # c : int -> EAX : boolean
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # EAX = c
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           0/r32/EAX   8/disp8         .                 # copy *(EBP+8) to EAX
+    # if (EAX < '0') return false
+    3d/compare-EAX-with  0x30/imm32/0
+    7c/jump-if-lesser  $is-alphanumeric?:false/disp8
+    # if (EAX <= '9') return true
+    3d/compare-EAX-with  0x39/imm32/9
+    7e/jump-if-lesser-or-equal  $is-alphanumeric?:true/disp8
+    # if (EAX < 'A') return false
+    3d/compare-EAX-with  0x41/imm32/A
+    7c/jump-if-lesser  $is-alphanumeric?:false/disp8
+    # if (EAX <= 'Z') return true
+    3d/compare-EAX-with  0x5a/imm32/Z
+    7e/jump-if-lesser-or-equal  $is-alphanumeric?:true/disp8
+    # if (EAX < 'a') return false
+    3d/compare-EAX-with  0x61/imm32/a
+    7c/jump-if-lesser  $is-alphanumeric?:false/disp8
+    # if (EAX <= 'z') return true
+    3d/compare-EAX-with  0x7a/imm32/z
+    7e/jump-if-lesser-or-equal  $is-alphanumeric?:true/disp8
+    # return false
+$is-alphanumeric?:false:
+    b8/copy-to-EAX  0/imm32/false
+    eb/jump  $is-alphanumeric?:end/disp8
+$is-alphanumeric?:true:
+    b8/copy-to-EAX  1/imm32/true
+$is-alphanumeric?:end:
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-emit-string-literal-data:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # var slice/ECX = '"abc"/d'
+    68/push  _test-slice-abc-limit/imm32
+    68/push  _test-slice-abc/imm32
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # emit-string-literal-data(_test-output-stream, slice)
+    # . . push args
+    51/push-ECX
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  emit-string-literal-data/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "result: ^")
+#?     # . . push args
+#?     68/push  "result: ^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-stream-equal(_test-output-stream, "3/imm32 61/a 62/b 63/c ", msg)
+    # . . push args
+    68/push  "F - test-emit-string-literal-data"/imm32
+    68/push  "0x00000003/imm32 61/a 62/b 63/c "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-emit-string-literal-data-empty:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # var slice/ECX = '""'
+    68/push  0/imm32/end
+    68/push  0/imm32/start
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # emit-string-literal-data(_test-output-stream, slice)
+    # . . push args
+    51/push-ECX
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  emit-string-literal-data/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "result: ^")
+#?     # . . push args
+#?     68/push  "result: ^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-stream-equal(_test-output-stream, "0/imm32 ", msg)
+    # . . push args
+    68/push  "F - test-emit-string-literal-data-empty"/imm32
+    68/push  "0x00000000/imm32 "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+# just to keep things simple
+test-emit-string-literal-data-no-metadata-for-non-alphanumerics:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # var slice/ECX = '"a b"'
+    68/push  _test-slice-a-space-b-limit/imm32
+    68/push  _test-slice-a-space-b/imm32
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # emit-string-literal-data(_test-output-stream, slice)
+    # . . push args
+    51/push-ECX
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  emit-string-literal-data/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "result: ^")
+#?     # . . push args
+#?     68/push  "result: ^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-stream-equal(_test-output-stream, "3/imm32 61/a 20 62/b ", msg)  # ideally we'd like to say '20/space' but that requires managing names for codepoints
+    # . . push args
+    68/push  "F - test-emit-string-literal-data-no-metadata-for-non-alphanumerics"/imm32
+    68/push  "0x00000003/imm32 61/a 20 62/b "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-emit-string-literal-data-handles-escape-sequences:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # var slice/ECX = '"a\"b"'
+    68/push  _test-slice-a-dquote-b-limit/imm32
+    68/push  _test-slice-a-dquote-b/imm32
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # emit-string-literal-data(_test-output-stream, slice)
+    # . . push args
+    51/push-ECX
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  emit-string-literal-data/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "result: ^")
+#?     # . . push args
+#?     68/push  "result: ^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-stream-equal(_test-output-stream, "3/imm32 61/a 22 62/b ", msg)
+    # . . push args
+    68/push  "F - test-emit-string-literal-data-handles-escape-sequences"/imm32
+    68/push  "0x00000003/imm32 61/a 22 62/b "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-emit-string-literal-data-handles-newline-escape:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # var slice/ECX = '"a\nb"'
+    68/push  _test-slice-a-newline-b-limit/imm32
+    68/push  _test-slice-a-newline-b/imm32
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # emit-string-literal-data(_test-output-stream, slice)
+    # . . push args
+    51/push-ECX
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  emit-string-literal-data/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "result: ^")
+#?     # . . push args
+#?     68/push  "result: ^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-stream-equal(_test-output-stream, "3/imm32 61/a 0a 62/b ", msg)
+    # . . push args
+    68/push  "F - test-emit-string-literal-data-handles-newline-escape"/imm32
+    68/push  "0x00000003/imm32 61/a 0a 62/b "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+# emit everything from a word except the initial datum
+emit-metadata:  # out : (address buffered-file), word : (address slice)
+    # pseudocode
+    #   var slice = {0, word->end}
+    #   curr = word->start
+    #   if *curr == '"'
+    #     curr = skip-string-in-slice(curr, word->end)
+    #   else
+    #     while true
+    #       if curr == word->end
+    #         return
+    #       if *curr == '/'
+    #         break
+    #       ++curr
+    #   slice->start = curr
+    #   write-slice-buffered(out, slice)
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+    51/push-ECX
+    52/push-EDX
+    53/push-EBX
+    56/push-ESI
+    # ESI = word
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   0xc/disp8       .                 # copy *(EBP+12) to ESI
+    # curr/ECX = word->start
+    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           1/r32/ECX   .               .                 # copy *ESI to ECX
+    # end/EDX = word->end
+    8b/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           2/r32/EDX   4/disp8         .                 # copy *(ESI+4) to EDX
+    # var slice/EBX = {0, end}
+    52/push-EDX
+    68/push  0/imm32
+    89/copy                         3/mod/direct    3/rm32/EBX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBX
+    # EAX = 0
+    b8/copy-to-EAX  0/imm32
+$emit-metadata:check-for-string-literal:
+    # -  if (*curr == '"') curr = skip-string-in-slice(curr, end)
+    8a/copy-byte                    0/mod/indirect  1/rm32/ECX    .           .             .           0/r32/AL    .               .                 # copy byte at *ECX to AL
+    3d/compare-EAX-and  0x22/imm32/dquote
+    75/jump-if-not-equal  $emit-metadata:skip-datum-loop/disp8
+$emit-metadata:skip-string-literal:
+    # . EAX = skip-string-in-slice(curr, end)
+    # . . push args
+    52/push-EDX
+    51/push-ECX
+    # . . call
+    e8/call  skip-string-in-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . curr = EAX
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           0/r32/EAX   .               .                 # copy EAX to ECX
+    eb/jump  $emit-metadata:emit/disp8
+$emit-metadata:skip-datum-loop:
+    # - otherwise scan for '/'
+    # if (curr == end) return
+    39/compare                      3/mod/direct    1/rm32/ECX    .           .             .           2/r32/EDX   .               .                 # compare ECX and EDX
+    74/jump-if-equal  $emit-metadata:end/disp8
+    # if (*curr == '/') break
+    8a/copy-byte                    0/mod/indirect  1/rm32/ECX    .           .             .           0/r32/AL    .               .                 # copy byte at *ECX to AL
+    3d/compare-EAX-and  0x2f/imm32/slash
+    74/jump-if-equal  $emit-metadata:emit/disp8
+    # ++curr
+    41/increment-ECX
+    eb/jump  $emit-metadata:skip-datum-loop/disp8
+$emit-metadata:emit:
+    # slice->start = ECX
+    89/copy                         0/mod/indirect  3/rm32/EBX    .           .             .           1/r32/ECX   .               .                 # copy ECX to *EBX
+    # write-slice-buffered(out, slice)
+    # . . push args
+    53/push-EBX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  write-slice-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           8/imm32      .                    # add to ESP
+$emit-metadata:end:
+    # . reclaim locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           8/imm32      .                    # add to ESP
+    # . restore registers
+    5e/pop-to-ESI
+    5b/pop-to-EBX
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-emit-metadata:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # (EAX..ECX) = "abc/def"
+    b8/copy-to-EAX  "abc/def"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # var slice/ECX = {EAX, ECX}
+    51/push-ECX
+    50/push-EAX
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # emit-metadata(_test-output-buffered-file, slice)
+    # . . push args
+    51/push-ECX
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  emit-metadata/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-stream-equal(_test-output-stream, "/def", msg)  # important that there's no leading space
+    # . . push args
+    68/push  "F - test-emit-metadata"/imm32
+    68/push  "/def"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-emit-metadata-none:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # (EAX..ECX) = "abc"
+    b8/copy-to-EAX  "abc"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # var slice/ECX = {EAX, ECX}
+    51/push-ECX
+    50/push-EAX
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # emit-metadata(_test-output-buffered-file, slice)
+    # . . push args
+    51/push-ECX
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  emit-metadata/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-stream-equal(_test-output-stream, "", msg)
+    # . . push args
+    68/push  "F - test-emit-metadata-none"/imm32
+    68/push  ""/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-emit-metadata-multiple:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # (EAX..ECX) = "abc/def/ghi"
+    b8/copy-to-EAX  "abc/def/ghi"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # var slice/ECX = {EAX, ECX}
+    51/push-ECX
+    50/push-EAX
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # emit-metadata(_test-output-buffered-file, slice)
+    # . . push args
+    51/push-ECX
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  emit-metadata/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-stream-equal(_test-output-stream, "/def/ghi", msg)  # important that there's no leading space
+    # . . push args
+    68/push  "F - test-emit-metadata-multiple"/imm32
+    68/push  "/def/ghi"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-emit-metadata-when-no-datum:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # var slice/ECX = "/abc"
+    b8/copy-to-EAX  "/abc"/imm32
+    # . push end/ECX
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    51/push-ECX
+    # . push curr/EAX
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . save stack pointer
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # emit-metadata(_test-output-buffered-file, slice)
+    # . . push args
+    51/push-ECX
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  emit-metadata/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-stream-equal(_test-output-stream, "/abc", msg)  # nothing skipped
+    # . . push args
+    68/push  "F - test-emit-metadata-when-no-datum"/imm32
+    68/push  "/abc"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-emit-metadata-in-string-literal:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # var slice/ECX = "\"abc/def\"/ghi"
+    68/push  _test-slice-literal-string-with-limit/imm32
+    68/push  _test-slice-literal-string/imm32/start
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # emit-metadata(_test-output-buffered-file, slice)
+    # . . push args
+    51/push-ECX
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  emit-metadata/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "result: ^")
+#?     # . . push args
+#?     68/push  "result: ^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # check-stream-equal(_test-output-stream, "/ghi", msg)  # important that there's no leading space
+    # . . push args
+    68/push  "F - test-emit-metadata-in-string-literal"/imm32
+    68/push  "/ghi"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+# (re)compute the bounds of the next word in the line
+# return empty string on reaching end of file
+next-word-or-string:  # line : (address stream byte), out : (address slice)
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+    51/push-ECX
+    56/push-ESI
+    57/push-EDI
+    # ESI = line
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   8/disp8         .                 # copy *(EBP+8) to ESI
+    # EDI = out
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           7/r32/EDI   0xc/disp8       .                 # copy *(EBP+12) to EDI
+    # skip-chars-matching(line, ' ')
+    # . . push args
+    68/push  0x20/imm32/space
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  skip-chars-matching/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+$next-word-or-string:check0:
+    # if (line->read >= line->write) clear out and return
+    # . EAX = line->read
+    8b/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           0/r32/EAX   4/disp8         .                 # copy *(ESI+4) to EAX
+    # . if (EAX < line->write) goto next check
+    3b/compare                      0/mod/indirect  6/rm32/ESI    .           .             .           0/r32/EAX   .               .                 # compare EAX with *ESI
+    7c/jump-if-lesser  $next-word-or-string:check-for-comment/disp8
+    # . return out = {0, 0}
+    c7          0/subop/copy        0/mod/direct    7/rm32/EDI    .           .             .           .           .               0/imm32           # copy to *EDI
+    c7          0/subop/copy        1/mod/*+disp8   7/rm32/EDI    .           .             .           .           4/disp8         0/imm32           # copy to *(EDI+4)
+    eb/jump  $next-word-or-string:end/disp8
+$next-word-or-string:check-for-comment:
+    # out->start = &line->data[line->read]
+    8b/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           1/r32/ECX   4/disp8         .                 # copy *(ESI+4) to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    6/base/ESI  1/index/ECX   .           0/r32/EAX   0xc/disp8       .                 # copy ESI+ECX+12 to EAX
+    89/copy                         0/mod/indirect  7/rm32/EDI    .           .             .           0/r32/EAX   .               .                 # copy EAX to *EDI
+    # if line->data[line->read] == '#'
+    # . EAX = line->data[line->read]
+    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
+    8a/copy-byte                    1/mod/*+disp8   4/rm32/sib    6/base/ESI  1/index/ECX   .           0/r32/AL    0xc/disp8       .                 # copy byte at *(ESI+ECX+12) to AL
+    # . compare
+    3d/compare-EAX-and  0x23/imm32/pound
+    75/jump-if-not-equal  $next-word-or-string:check-for-string-literal/disp8
+$next-word-or-string:comment:
+    # out->end = &line->data[line->write]
+    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           0/r32/EAX   .               .                 # copy *ESI to EAX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    6/base/ESI  0/index/EAX   .           0/r32/EAX   0xc/disp8       .                 # copy ESI+EAX+12 to EAX
+    89/copy                         1/mod/*+disp8   7/rm32/EDI    .           .             .           0/r32/EAX   4/disp8         .                 # copy EAX to *(EDI+4)
+    # line->read = line->write  # skip rest of line
+    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           0/r32/EAX   .               .                 # copy *ESI to EAX
+    89/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           0/r32/EAX   4/disp8         .                 # copy EAX to *(ESI+4)
+    # return
+    eb/jump  $next-word-or-string:end/disp8
+$next-word-or-string:check-for-string-literal:
+    # if line->data[line->read] == '"'
+    # . EAX = line->data[line->read]
+    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
+    8a/copy-byte                    1/mod/*+disp8   4/rm32/sib    6/base/ESI  1/index/ECX   .           0/r32/AL    0xc/disp8       .                 # copy byte at *(ESI+ECX+12) to AL
+    # . compare
+    3d/compare-EAX-and  0x22/imm32/dquote
+    75/jump-if-not-equal  $next-word-or-string:regular-word/disp8
+$next-word-or-string:string-literal:
+    # skip-string(line)
+    # . . push args
+    56/push-ESI
+    # . . call
+    e8/call  skip-string/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # fall through
+$next-word-or-string:regular-word:
+    # skip-chars-not-matching-whitespace(line)  # including trailing newline
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  skip-chars-not-matching-whitespace/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # out->end = &line->data[line->read]
+    8b/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           1/r32/ECX   4/disp8         .                 # copy *(ESI+4) to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    6/base/ESI  1/index/ECX   .           0/r32/EAX   0xc/disp8       .                 # copy ESI+ECX+12 to EAX
+    89/copy                         1/mod/*+disp8   7/rm32/EDI    .           .             .           0/r32/EAX   4/disp8         .                 # copy EAX to *(EDI+4)
+$next-word-or-string:end:
+    # . restore registers
+    5f/pop-to-EDI
+    5e/pop-to-ESI
+    59/pop-to-ECX
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-next-word-or-string:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # var slice/ECX = {0, 0}
+    68/push  0/imm32/end
+    68/push  0/imm32/start
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # write(_test-input-stream, "  ab")
+    # . . push args
+    68/push  "  ab"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # next-word-or-string(_test-input-stream, slice)
+    # . . push args
+    51/push-ECX
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  next-word-or-string/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check-ints-equal(_test-input-stream->read, 4, msg)
+    # . . push args
+    68/push  "F - test-next-word-or-string/updates-stream-read-correctly"/imm32
+    68/push  4/imm32
+    b8/copy-to-EAX  _test-input-stream/imm32
+    ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           4/disp8         .                 # push *(EAX+4)
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # check-ints-equal(slice->start - _test-input-stream->data, 2, msg)
+    # . check-ints-equal(slice->start - _test-input-stream, 14, msg)
+    # . . push args
+    68/push  "F - test-next-word-or-string: start"/imm32
+    68/push  0xe/imm32
+    # . . push slice->start - _test-input-stream
+    8b/copy                         0/mod/indirect  1/rm32/ECX    .           .             .           0/r32/EAX   .               .                 # copy *ECX to EAX
+    81          5/subop/subtract    3/mod/direct    0/rm32/EAX    .           .             .           .           .               _test-input-stream/imm32 # subtract from EAX
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # check-ints-equal(slice->end - _test-input-stream->data, 4, msg)
+    # . check-ints-equal(slice->end - _test-input-stream, 16, msg)
+    # . . push args
+    68/push  "F - test-next-word-or-string: end"/imm32
+    68/push  0x10/imm32
+    # . . push slice->end - _test-input-stream
+    8b/copy                         1/mod/*+disp8   1/rm32/ECX    .           .             .           0/r32/EAX   4/disp8         .                 # copy *(ECX+4) to EAX
+    81          5/subop/subtract    3/mod/direct    0/rm32/EAX    .           .             .           .           .               _test-input-stream/imm32 # subtract from EAX
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-next-word-or-string-returns-whole-comment:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # var slice/ECX = {0, 0}
+    68/push  0/imm32/end
+    68/push  0/imm32/start
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # write(_test-input-stream, "  # a")
+    # . . push args
+    68/push  "  # a"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # next-word-or-string(_test-input-stream, slice)
+    # . . push args
+    51/push-ECX
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  next-word-or-string/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check-ints-equal(_test-input-stream->read, 5, msg)
+    # . . push args
+    68/push  "F - test-next-word-or-string-returns-whole-comment/updates-stream-read-correctly"/imm32
+    68/push  5/imm32
+    b8/copy-to-EAX  _test-input-stream/imm32
+    ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           4/disp8         .                 # push *(EAX+4)
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # check-ints-equal(slice->start - _test-input-stream->data, 2, msg)
+    # . check-ints-equal(slice->start - _test-input-stream, 14, msg)
+    # . . push args
+    68/push  "F - test-next-word-or-string-returns-whole-comment: start"/imm32
+    68/push  0xe/imm32
+    # . . push slice->start - _test-input-stream
+    8b/copy                         0/mod/indirect  1/rm32/ECX    .           .             .           0/r32/EAX   .               .                 # copy *ECX to EAX
+    81          5/subop/subtract    3/mod/direct    0/rm32/EAX    .           .             .           .           .               _test-input-stream/imm32 # subtract from EAX
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # check-ints-equal(slice->end - _test-input-stream->data, 5, msg)
+    # . check-ints-equal(slice->end - _test-input-stream, 17, msg)
+    # . . push args
+    68/push  "F - test-next-word-or-string-returns-whole-comment: end"/imm32
+    68/push  0x11/imm32
+    # . . push slice->end - _test-input-stream
+    8b/copy                         1/mod/*+disp8   1/rm32/ECX    .           .             .           0/r32/EAX   4/disp8         .                 # copy *(ECX+4) to EAX
+    81          5/subop/subtract    3/mod/direct    0/rm32/EAX    .           .             .           .           .               _test-input-stream/imm32 # subtract from EAX
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-next-word-or-string-returns-empty-string-on-eof:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # var slice/ECX = {0, 0}
+    68/push  0/imm32/end
+    68/push  0/imm32/start
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # write nothing to _test-input-stream
+    # next-word-or-string(_test-input-stream, slice)
+    # . . push args
+    51/push-ECX
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  next-word-or-string/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check-ints-equal(slice->end - slice->start, 0, msg)
+    # . . push args
+    68/push  "F - test-next-word-or-string-returns-empty-string-on-eof"/imm32
+    68/push  0/imm32
+    # . . push slice->end - slice->start
+    8b/copy                         1/mod/*+disp8   1/rm32/ECX    .           .             .           0/r32/EAX   4/disp8         .                 # copy *(ECX+4) to EAX
+    2b/subtract                     0/mod/indirect  1/rm32/ECX    .           .             .           0/r32/EAX   .               .                 # subtract *ECX from EAX
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-next-word-or-string-returns-whole-string:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # var slice/ECX = {0, 0}
+    68/push  0/imm32/end
+    68/push  0/imm32/start
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # write(_test-input-stream, " \"a b\"/imm32 ")
+    # . . push args
+    68/push  " \"a b\"/imm32 "/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # next-word-or-string(_test-input-stream, slice)
+    # . . push args
+    51/push-ECX
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  next-word-or-string/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check-ints-equal(slice->start - _test-input-stream->data, 1, msg)
+    # . check-ints-equal(slice->start - _test-input-stream, 13, msg)
+    # . . push args
+    68/push  "F - test-next-word-or-string-returns-whole-string: start"/imm32
+    68/push  0xd/imm32
+    # . . push slice->start - _test-input-stream
+    8b/copy                         0/mod/indirect  1/rm32/ECX    .           .             .           0/r32/EAX   .               .                 # copy *ECX to EAX
+    81          5/subop/subtract    3/mod/direct    0/rm32/EAX    .           .             .           .           .               _test-input-stream/imm32 # subtract from EAX
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # check-ints-equal(slice->end - _test-input-stream->data, 12, msg)
+    # . check-ints-equal(slice->end - _test-input-stream, 24, msg)
+    # . . push args
+    68/push  "F - test-next-word-or-string-returns-whole-string: end"/imm32
+    68/push  0x18/imm32
+    # . . push slice->end - _test-input-stream
+    8b/copy                         1/mod/*+disp8   1/rm32/ECX    .           .             .           0/r32/EAX   4/disp8         .                 # copy *(ECX+4) to EAX
+    81          5/subop/subtract    3/mod/direct    0/rm32/EAX    .           .             .           .           .               _test-input-stream/imm32 # subtract from EAX
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-next-word-or-string-returns-string-with-escapes:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # var slice/ECX = {0, 0}
+    68/push  0/imm32/end
+    68/push  0/imm32/start
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # write(_test-input-stream, " \"a\\\"b\"/x")
+    # . . push args
+    68/push  " \"a\\\"b\"/x"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # next-word-or-string(_test-input-stream, slice)
+    # . . push args
+    51/push-ECX
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  next-word-or-string/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check-ints-equal(slice->start - _test-input-stream->data, 1, msg)
+    # . check-ints-equal(slice->start - _test-input-stream, 13, msg)
+    # . . push args
+    68/push  "F - test-next-word-or-string-returns-string-with-escapes: start"/imm32
+    68/push  0xd/imm32
+    # . . push slice->start - _test-input-stream
+    8b/copy                         0/mod/indirect  1/rm32/ECX    .           .             .           0/r32/EAX   .               .                 # copy *ECX to EAX
+    81          5/subop/subtract    3/mod/direct    0/rm32/EAX    .           .             .           .           .               _test-input-stream/imm32 # subtract from EAX
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # check-ints-equal(slice->end - _test-input-stream->data, 9, msg)
+    # . check-ints-equal(slice->end - _test-input-stream, 21, msg)
+    # . . push args
+    68/push  "F - test-next-word-or-string-returns-string-with-escapes: end"/imm32
+    68/push  0x15/imm32
+    # . . push slice->end - _test-input-stream
+    8b/copy                         1/mod/*+disp8   1/rm32/ECX    .           .             .           0/r32/EAX   4/disp8         .                 # copy *(ECX+4) to EAX
+    81          5/subop/subtract    3/mod/direct    0/rm32/EAX    .           .             .           .           .               _test-input-stream/imm32 # subtract from EAX
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+# update line->read to end of string literal surrounded by double quotes
+# line->read must start out at a double-quote
+skip-string:  # line : (address stream)
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+    51/push-ECX
+    52/push-EDX
+    # ECX = line
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .                         1/r32/ECX   8/disp8         .                 # copy *(EBP+8) to ECX
+    # EAX = skip-string-in-slice(&line->data[line->read], &line->data[line->write])
+    # . . push &line->data[line->write]
+    8b/copy                         1/mod/*+disp8   1/rm32/ECX    .           .                         2/r32/EDX   8/disp8         .                 # copy *(ECX+8) to EDX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    1/base/ECX  2/index/EDX   .           2/r32/EDX   0xc/disp8       .                 # copy ECX+EDX+12 to EDX
+    52/push-EDX
+    # . . push &line->data[line->read]
+    8b/copy                         1/mod/*+disp8   1/rm32/ECX    .           .                         2/r32/EDX   4/disp8         .                 # copy *(ECX+4) to EDX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    1/base/ECX  2/index/EDX   .           2/r32/EDX   0xc/disp8       .                 # copy ECX+EDX+12 to EDX
+    52/push-EDX
+    # . . call
+    e8/call  skip-string-in-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # line->read = EAX - line->data
+    29/subtract                     3/mod/direct    0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # subtract ECX from EAX
+    2d/subtract-from-EAX  0xc/imm32
+    89/copy                         1/mod/*+disp8   1/rm32/ECX    .           .                         0/r32/EAX   4/disp8         .                 # copy EAX to *(ECX+4)
+$skip-string:end:
+    # . restore registers
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-skip-string:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . write(_test-input-stream, "\"abc\" def")
+    # .                   indices:  0123 45
+    # . . push args
+    68/push  "\"abc\" def"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # precondition: line->read == 0
+    # . . push args
+    68/push  "F - test-skip-string/precondition"/imm32
+    68/push  0/imm32
+    b8/copy-to-EAX  _test-input-stream/imm32
+    ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           4/disp8         .                 # push *(EAX+4)
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # skip-string(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  skip-string/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-ints-equal(line->read, 5, msg)
+    # . . push args
+    68/push  "F - test-skip-string"/imm32
+    68/push  5/imm32
+    b8/copy-to-EAX  _test-input-stream/imm32
+    ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           4/disp8         .                 # push *(EAX+4)
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-skip-string-ignores-spaces:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . write(_test-input-stream, "\"a b\"/yz")
+    # .                   indices:  0123 45
+    # . . push args
+    68/push  "\"a b\"/yz"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # precondition: line->read == 0
+    # . . push args
+    68/push  "F - test-skip-string-ignores-spaces/precondition"/imm32
+    68/push  0/imm32
+    b8/copy-to-EAX  _test-input-stream/imm32
+    ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           4/disp8         .                 # push *(EAX+4)
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # skip-string(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  skip-string/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-ints-equal(line->read, 5, msg)
+    # . . push args
+    68/push  "F - test-skip-string-ignores-spaces"/imm32
+    68/push  5/imm32
+    b8/copy-to-EAX  _test-input-stream/imm32
+    ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           4/disp8         .                 # push *(EAX+4)
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-skip-string-ignores-escapes:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . write(_test-input-stream, "\"a\\\"b\"/yz")
+    # .                   indices:  01 2 34 56
+    # . . push args
+    68/push  "\"a\\\"b\"/yz"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # precondition: line->read == 0
+    # . . push args
+    68/push  "F - test-skip-string-ignores-escapes/precondition"/imm32
+    68/push  0/imm32
+    b8/copy-to-EAX  _test-input-stream/imm32
+    ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           4/disp8         .                 # push *(EAX+4)
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # skip-string(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  skip-string/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-ints-equal(line->read, 6, msg)
+    # . . push args
+    68/push  "F - test-skip-string-ignores-escapes"/imm32
+    68/push  6/imm32
+    b8/copy-to-EAX  _test-input-stream/imm32
+    ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           4/disp8         .                 # push *(EAX+4)
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-skip-string-works-from-mid-stream:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . write(_test-input-stream, "0 \"a\\\"b\"/yz")
+    # .                   indices:  01 2 34 56
+    # . . push args
+    68/push  "0 \"a\\\"b\"/yz"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # precondition: line->read == 2
+    c7          0/subop/copy        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           4/disp8         2/imm32           # copy to *(EAX+4)
+    # skip-string(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  skip-string/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-ints-equal(line->read, 8, msg)
+    # . . push args
+    68/push  "F - test-skip-string-works-from-mid-stream"/imm32
+    68/push  8/imm32
+    b8/copy-to-EAX  _test-input-stream/imm32
+    ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           4/disp8         .                 # push *(EAX+4)
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+skip-string-in-slice:  # curr : (address byte), end : (address byte) -> new_curr/EAX
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    51/push-ECX
+    52/push-EDX
+    53/push-EBX
+    # ECX = curr
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .                         1/r32/ECX   8/disp8         .                 # copy *(EBP+8) to ECX
+    # EDX = end
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .                         2/r32/EDX   0xc/disp8         .               # copy *(EBP+12) to EDX
+    # EAX = 0
+    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
+    # skip initial dquote
+    41/increment-ECX
+$skip-string-in-slice:loop:
+    # if (curr >= end) return curr
+    39/compare                      3/mod/direct    1/rm32/ECX    .           .             .           2/r32/EDX   .               .                 # compare ECX with EDX
+    73/jump-if-greater-unsigned-or-equal  $skip-string-in-slice:return-curr/disp8
+    # AL = *curr
+    8a/copy-byte                    0/mod/indirect  1/rm32/ECX    .           .             .           0/r32/AL    .               .                 # copy byte at *ECX to AL
+$skip-string-in-slice:dquote:
+    # if (EAX == '"') break
+    3d/compare-EAX-and  0x22/imm32/double-quote
+    74/jump-if-equal  $skip-string-in-slice:break/disp8
+$skip-string-in-slice:check-for-escape:
+    # if (EAX == '\') escape next char
+    3d/compare-EAX-and  0x5c/imm32/backslash
+    75/jump-if-not-equal  $skip-string-in-slice:continue/disp8
+$skip-string-in-slice:escape:
+    41/increment-ECX
+$skip-string-in-slice:continue:
+    # ++curr
+    41/increment-ECX
+    eb/jump  $skip-string-in-slice:loop/disp8
+$skip-string-in-slice:break:
+    # skip final dquote
+    41/increment-ECX
+$skip-string-in-slice:return-curr:
+    # return curr
+    89/copy                         3/mod/direct    0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy ECX to EAX
+$skip-string-in-slice:end:
+    # . restore registers
+    5b/pop-to-EBX
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-skip-string-in-slice:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup: (EAX..ECX) = "\"abc\" def"
+    b8/copy-to-EAX  "\"abc\" def"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # EAX = skip-string-in-slice(EAX, ECX)
+    # . . push args
+    51/push-ECX
+    50/push-EAX
+    # . . call
+    e8/call  skip-string-in-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check-ints-equal(ECX-EAX, 4, msg)  # number of chars remaining after the string literal
+    # . . push args
+    68/push  "F - test-skip-string-in-slice"/imm32
+    68/push  4/imm32
+    # . . push ECX-EAX
+    29/subtract                     3/mod/direct    1/rm32/ECX    .           .             .           0/r32/EAX   .               .                 # subtract EAX from ECX
+    51/push-ECX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-skip-string-in-slice-ignores-spaces:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup: (EAX..ECX) = "\"a b\"/yz"
+    b8/copy-to-EAX  "\"a b\"/yz"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # EAX = skip-string-in-slice(EAX, ECX)
+    # . . push args
+    51/push-ECX
+    50/push-EAX
+    # . . call
+    e8/call  skip-string-in-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check-ints-equal(ECX-EAX, 3, msg)  # number of chars remaining after the string literal
+    # . . push args
+    68/push  "F - test-skip-string-in-slice-ignores-spaces"/imm32
+    68/push  3/imm32
+    # . . push ECX-EAX
+    29/subtract                     3/mod/direct    1/rm32/ECX    .           .             .           0/r32/EAX   .               .                 # subtract EAX from ECX
+    51/push-ECX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-skip-string-in-slice-ignores-escapes:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup: (EAX..ECX) = "\"a\\\"b\"/yz"
+    b8/copy-to-EAX  "\"a\\\"b\"/yz"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # EAX = skip-string-in-slice(EAX, ECX)
+    # . . push args
+    51/push-ECX
+    50/push-EAX
+    # . . call
+    e8/call  skip-string-in-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check-ints-equal(ECX-EAX, 3, msg)  # number of chars remaining after the string literal
+    # . . push args
+    68/push  "F - test-skip-string-in-slice-ignores-escapes"/imm32
+    68/push  3/imm32
+    # . . push ECX-EAX
+    29/subtract                     3/mod/direct    1/rm32/ECX    .           .             .           0/r32/EAX   .               .                 # subtract EAX from ECX
+    51/push-ECX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-skip-string-in-slice-stops-at-end:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup: (EAX..ECX) = "\"abc"  # unbalanced dquote
+    b8/copy-to-EAX  "\"abc"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # EAX = skip-string-in-slice(EAX, ECX)
+    # . . push args
+    51/push-ECX
+    50/push-EAX
+    # . . call
+    e8/call  skip-string-in-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check-ints-equal(ECX-EAX, 0, msg)  # skipped to end of slice
+    # . . push args
+    68/push  "F - test-skip-string-in-slice-stops-at-end"/imm32
+    68/push  0/imm32
+    # . . push ECX-EAX
+    29/subtract                     3/mod/direct    1/rm32/ECX    .           .             .           0/r32/EAX   .               .                 # subtract EAX from ECX
+    51/push-ECX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+string-length-at-start-of-slice:  # curr : (address byte), end : (address byte) -> length/EAX
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    51/push-ECX
+    52/push-EDX
+    53/push-EBX
+    # ECX = curr
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .                         1/r32/ECX   8/disp8         .                 # copy *(EBP+8) to ECX
+    # EDX = end
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .                         2/r32/EDX   0xc/disp8         .               # copy *(EBP+12) to EDX
+    # length/EAX = 0
+    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
+    # EBX = 0
+    31/xor                          3/mod/direct    3/rm32/EBX    .           .             .           3/r32/EBX   .               .                 # clear EBX
+    # skip initial dquote
+    41/increment-ECX
+$string-length-at-start-of-slice:loop:
+    # if (curr >= end) return length
+    39/compare                      3/mod/direct    1/rm32/ECX    .           .             .           2/r32/EDX   .               .                 # compare ECX with EDX
+    73/jump-if-greater-unsigned-or-equal  $string-length-at-start-of-slice:end/disp8
+    # BL = *curr
+    8a/copy-byte                    0/mod/indirect  1/rm32/ECX    .           .             .           3/r32/BL    .               .                 # copy byte at *ECX to BL
+$string-length-at-start-of-slice:dquote:
+    # if (EBX == '"') break
+    81          7/subop/compare     3/mod/direct    3/rm32/EBX    .           .             .           .           .               0x22/imm32/dquote # compare EBX
+    74/jump-if-equal  $string-length-at-start-of-slice:end/disp8
+$string-length-at-start-of-slice:check-for-escape:
+    # if (EBX == '\') escape next char
+    81          7/subop/compare     3/mod/direct    3/rm32/EBX    .           .             .           .           .               0x5c/imm32/backslash # compare EBX
+    75/jump-if-not-equal  $string-length-at-start-of-slice:continue/disp8
+$string-length-at-start-of-slice:escape:
+    # increment curr but not result
+    41/increment-ECX
+$string-length-at-start-of-slice:continue:
+    # ++result
+    40/increment-EAX
+    # ++curr
+    41/increment-ECX
+    eb/jump  $string-length-at-start-of-slice:loop/disp8
+$string-length-at-start-of-slice:end:
+    # . restore registers
+    5b/pop-to-EBX
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-string-length-at-start-of-slice:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup: (EAX..ECX) = "\"abc\" def"
+    b8/copy-to-EAX  "\"abc\" def"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # EAX = string-length-at-start-of-slice(EAX, ECX)
+    # . . push args
+    51/push-ECX
+    50/push-EAX
+    # . . call
+    e8/call  string-length-at-start-of-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check-ints-equal(EAX, 3, msg)
+    # . . push args
+    68/push  "F - test-string-length-at-start-of-slice"/imm32
+    68/push  3/imm32
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-string-length-at-start-of-slice-escaped:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup: (EAX..ECX) = "\"ab\\c\" def"
+    b8/copy-to-EAX  "\"ab\\c\" def"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # EAX = string-length-at-start-of-slice(EAX, ECX)
+    # . . push args
+    51/push-ECX
+    50/push-EAX
+    # . . call
+    e8/call  string-length-at-start-of-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check-ints-equal(EAX, 3, msg)
+    # . . push args
+    68/push  "F - test-string-length-at-start-of-slice-escaped"/imm32
+    68/push  3/imm32
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+== data
+
+Next-string-literal:  # tracks the next auto-generated variable name
+  1/imm32
+
+# length-prefixed string containing just a single space
+Space:
+    # size
+    1/imm32
+    # data
+    20/space
+
+# length-prefixed string containing just a single slash
+Slash:
+    # size
+    1/imm32
+    # data
+    2f/slash
+
+_test-slice-abc:
+  22/dquote 61/a 62/b 63/c 22/dquote  # "abc"
+  2f/slash 64/d
+_test-slice-abc-limit:
+
+_test-slice-a-space-b:
+  22/dquote 61/a 20/space 62/b 22/dquote  # "a b"
+_test-slice-a-space-b-limit:
+
+_test-slice-a-dquote-b:
+  22/dquote 61/a 5c/backslash 22/dquote 62/b 22/dquote  # "a\"b"
+_test-slice-a-dquote-b-limit:
+
+_test-slice-a-newline-b:
+  22/dquote 61/a 5c/backslash 6e/n 62/b 22/dquote  # "a\nb"
+_test-slice-a-newline-b-limit:
+
+# "abc/def"/ghi
+_test-slice-literal-string:
+  22/dquote
+  61/a 62/b 63/c  # abc
+  2f/slash 64/d 65/e 66/f  # /def
+  22/dquote
+  2f/slash 67/g 68/h 69/i  # /ghi
+_test-slice-literal-string-with-limit:
+
+# . . vim:nowrap:textwidth=0
diff --git a/apps/factorial b/apps/factorial
new file mode 100755
index 00000000..b82be120
--- /dev/null
+++ b/apps/factorial
Binary files differdiff --git a/apps/factorial.subx b/apps/factorial.subx
new file mode 100644
index 00000000..e4b7a057
--- /dev/null
+++ b/apps/factorial.subx
@@ -0,0 +1,117 @@
+## compute the factorial of 5, and return the result in the exit code
+#
+# To run (from the subx directory):
+#   $ ./subx translate apps/factorial.subx -o apps/factorial
+#   $ ./subx run apps/factorial
+# Expected result:
+#   $ echo $?
+#   120
+#
+# You can also run the automated test suite:
+#   $ ./subx run apps/factorial test
+# Expected output:
+#   ........
+# Every '.' indicates a passing test. Failing tests get a 'F'.
+
+== code
+#   instruction                     effective address                                                   register    displacement    immediate
+# . op          subop               mod             rm32          base        index         scale       r32
+# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
+
+Entry:  # run tests if necessary, compute `factorial(5)` if not
+    # initialize heap
+    # . Heap = new-segment(64KB)
+    # . . push args
+    68/push  Heap/imm32
+    68/push  0x10000/imm32/64KB
+    # . . call
+    e8/call  new-segment/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+
+    # . prolog
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # - if argc > 1 and argv[1] == "test", then return run_tests()
+    # . argc > 1
+    81          7/subop/compare     1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0/disp8         1/imm32           # compare *EBP
+    7e/jump-if-lesser-or-equal  $run-main/disp8
+    # . argv[1] == "test"
+    # . . push args
+    68/push  "test"/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  kernel-string-equal?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . check result
+    3d/compare-EAX-and  1/imm32
+    75/jump-if-not-equal  $run-main/disp8
+    # . run-tests()
+    e8/call  run-tests/disp32
+    8b/copy                         0/mod/indirect  5/rm32/.disp32            .             .           0/r32/EAX   Num-test-failures/disp32          # copy *Num-test-failures to EAX
+    eb/jump  $main:end/disp8  # where EAX will get copied to EBX
+$run-main:
+    # - otherwise return factorial(5)
+    # . . push args
+    68/push  5/imm32
+    # . . call
+    e8/call  factorial/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+$main:end:
+    # syscall(exit, EAX)
+    89/copy                         3/mod/direct    3/rm32/EBX    .           .             .           0/r32/EAX   .               .                 # copy EAX to EBX
+    b8/copy-to-EAX  1/imm32/exit
+    cd/syscall  0x80/imm8
+
+factorial:  # n : int -> int/EAX
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    53/push-EBX
+    # EAX = 1 (base case)
+    b8/copy-to-EAX  1/imm32
+    # if (n <= 1) return
+    81          7/subop/compare     1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         1/imm32           # compare *(EBP+8)
+    7e/jump-if-<=  $factorial:end/disp8
+    # EBX = n-1
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .                         3/r32/EBX   8/disp8         .                 # copy *(EBP+8) to EBX
+    81          5/subop/subtract    3/mod/direct    3/rm32/EBX    .           .             .           .           .               1/imm32           # subtract from EBX
+    # EAX = factorial(n-1)
+    # . . push args
+    53/push-EBX
+    # . . call
+    e8/call  factorial/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # return n * factorial(n-1)
+    f7          4/subop/multiply    1/mod/*+disp8   5/rm32/EBP    .           .                                     8/disp8         .                 # multiply *(EBP+8) into EAX
+    # TODO: check for overflow
+$factorial:end:
+    # . epilog
+    5b/pop-to-EBX
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-factorial:
+    # factorial(5)
+    # . . push args
+    68/push  5/imm32
+    # . . call
+    e8/call  factorial/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-ints-equal(EAX, 120, msg)
+    # . . push args
+    68/push  "F - test-factorial"/imm32
+    68/push  0x78/imm32/expected-120
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # end
+    c3/return
+
+# . . vim:nowrap:textwidth=0
diff --git a/apps/handle b/apps/handle
new file mode 100755
index 00000000..b6794474
--- /dev/null
+++ b/apps/handle
Binary files differdiff --git a/apps/handle.subx b/apps/handle.subx
new file mode 100644
index 00000000..ba824f85
--- /dev/null
+++ b/apps/handle.subx
@@ -0,0 +1,412 @@
+# A sketch of Mu-style handles or kinda-safe pointers, that add a modicum of
+# checking to dynamically allocated memory.
+#
+# This approach avoids using 'allocate' directly in favor of two primitives:
+#   - 'new', which allocates some space (the 'payload'), stores the address
+#     along with an opaque 'alloc id' in a 'handle', and prepends the same
+#     alloc id to the payload.
+#   - 'lookup', which checks that the alloc id at the start of a handle matches
+#     the alloc id at the start of the payload before returning the address.
+#
+# Layout of a handle:
+#   offset 0: alloc id
+#   offset 4: address
+#
+# To run (from the subx directory):
+#   $ ./subx translate *.subx apps/handle.subx -o apps/handle
+#   $ ./subx run apps/handle
+# Expected result is a successful lookup followed by a hard abort:
+#   lookup succeeded
+#   lookup failed
+# (This file is a prototype. The 'tests' in it aren't real; failures are
+# expected.)
+
+== code
+#   instruction                     effective address                                                   register    displacement    immediate
+# . op          subop               mod             rm32          base        index         scale       r32
+# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
+
+# no Entry; the standard library runs all tests by default
+
+new:  # ad : (address allocation-descriptor), n : int, out : (address handle)
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+    51/push-ECX
+    52/push-EDX
+    # ECX = n+4
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           1/r32/ECX   0xc/disp8       .                 # copy *(EBP+12) to ECX
+    81          0/subop/add         3/mod/direct    1/rm32/ECX    .           .             .           .           .               4/imm32           # add to ECX
+    # EAX = allocate(ad, ECX)
+    # . . push args
+    51/push-ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  allocate/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # EDX = out
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           2/r32/EDX   0x10/disp8      .                 # copy *(EBP+16) to EDX
+    # out->address = EAX
+    89/copy                         1/mod/*+disp8   2/rm32/EDX    .           .             .           0/r32/EAX   4/disp8         .                 # copy EAX to *(EDX+4)
+    # if (EAX == 0) out->alloc_id = 0, return
+    3d/compare-EAX-and  0/imm32
+    75/jump-if-not-equal  $new:continue/disp8
+    c7          0/subop/copy        0/mod/indirect  2/rm32/EDX    .           .             .           .           .               0/imm32           # copy to *EDX
+    eb/jump  $new:end/disp8
+$new:continue:
+    # otherwise:
+    # ECX = *Next-alloc-id
+    8b/copy                         0/mod/indirect  5/rm32/.disp32            .             .           1/r32/ECX   Next-alloc-id/disp32              # copy *Next-alloc-id to ECX
+    # *EAX = *Next-alloc-id/ECX
+    89/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy ECX to *EAX
+    # out->alloc_id = *Next-alloc-id
+    89/copy                         0/mod/indirect  2/rm32/EDX    .           .             .           1/r32/ECX   .               .                 # copy ECX to *EDX
+    # increment *Next-alloc-id
+    ff          0/subop/increment   0/mod/indirect  5/rm32/.disp32            .             .           .           Next-alloc-id/disp32              # increment *Next-alloc-id
+$new:end:
+    # . restore registers
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-new:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # var heap/EDX : (address allocation-descriptor) = {0, 0}
+    68/push  0/imm32/limit
+    68/push  0/imm32/curr
+    89/copy                         3/mod/direct    2/rm32/EDX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EDX
+    # heap = new-segment(512)
+    # . . push args
+    52/push-EDX
+    68/push  0x200/imm32
+    # . . call
+    e8/call  new-segment/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # *Next-alloc-id = 0x34
+    c7          0/subop/copy        0/mod/indirect  5/rm32/.disp32            .             .           .     Next-alloc-id/disp32  0x34/imm32        # copy to *Next-alloc-id
+    # var handle/ECX = {0, 0}
+    68/push  0/imm32/address
+    68/push  0/imm32/alloc-id
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # new(heap, 2, handle/ECX)
+    # . . push args
+    51/push-ECX
+    68/push  2/imm32/size
+    52/push-EDX
+    # . . call
+    e8/call  new/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # check-ints-equal(handle->alloc_id, 0x34, msg)
+    # . . push args
+    68/push  "F - test-new: alloc id of handle"/imm32
+    68/push  0x34/imm32
+    ff          6/subop/push        0/mod/indirect  1/rm32/ECX    .           .             .           .           .               .                 # push *ECX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # check-ints-equal(*handle->address, 0x34, msg)
+    # . . push args
+    68/push  "F - test-new: alloc id of payload"/imm32
+    68/push  0x34/imm32
+    8b/copy                         1/mod/*+disp8   1/rm32/ECX    .           .             .           2/r32/EDX   4/disp8         .                 # copy *(ECX+4) to EDX
+    ff          6/subop/push        0/mod/indirect  2/rm32/EDX    .           .             .           .           .               .                 # push *EDX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # check-ints-equal(*Next-alloc-id, 0x35)
+    # . . push args
+    68/push  "F - test-new: next alloc id"/imm32
+    68/push  0x35/imm32
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Next-alloc-id/disp32              # copy to *Next-alloc-id
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # clean up
+    # . *Next-alloc-id = 1
+    c7          0/subop/copy        0/mod/indirect  5/rm32/.disp32            .             .           .     Next-alloc-id/disp32  1/imm32           # copy to *Next-alloc-id
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+_pending-test-new-failure:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . *Next-alloc-id = 0x34
+    c7          0/subop/copy        0/mod/indirect  5/rm32/.disp32            .             .           .           Next-alloc-id/disp32  0x34/imm32  # copy to *Next-alloc-id
+    # define an allocation-descriptor with no space left
+    # . var ad/EAX : (address allocation-descriptor) = {0x10, 0x10}
+    68/push  0x10/imm32/limit
+    68/push  0x10/imm32/curr
+    89/copy                         3/mod/direct    0/rm32/EAX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EAX
+    # . var handle/ECX = {random, random}
+    68/push  1234/imm32/address
+    68/push  5678/imm32/alloc-id
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # try to allocate
+    # . new(ad, 2, handle/ECX)
+    # . . push args
+    51/push-ECX
+    68/push  2/imm32/size
+    50/push-EAX
+    # . . call
+    e8/call  new/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # handle should be cleared
+    # . check-ints-equal(handle->alloc_id, 0, msg)
+    # . . push args
+    68/push  "F - test-new-failure: alloc id of handle"/imm32
+    68/push  0/imm32
+    ff          6/subop/push        0/mod/indirect  1/rm32/ECX    .           .             .           .           .               .                 # push *ECX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-ints-equal(handle->address, 0, msg)
+    # . . push args
+    68/push  "F - test-new-failure: address of handle"/imm32
+    68/push  0/imm32
+    ff          6/subop/push        1/mod/*+disp8   1/rm32/ECX    .           .             .           .           4/disp8         .                 # push *(ECX+4)
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # Next-alloc-id should be unmodified
+    # . check-ints-equal(*Next-alloc-id, 0x34)
+    # . . push args
+    68/push  "F - test-new-failure: next alloc id"/imm32
+    68/push  0x34/imm32
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Next-alloc-id/disp32              # copy to *Next-alloc-id
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # clean up
+    # . *Next-alloc-id = 1
+    c7          0/subop/copy        0/mod/indirect  5/rm32/.disp32            .             .           .     Next-alloc-id/disp32  1/imm32           # copy to *Next-alloc-id
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+lookup:  # h : (handle T) -> EAX : (address T)
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # - as a proof of concept for future inlining, uses no general-purpose registers besides the output (EAX)
+    # EAX = handle
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           0/r32/EAX   8/disp8         .                 # copy *(EBP+8) to EAX
+    # - inline {
+    # push handle->alloc_id
+    ff          6/subop/push        0/mod/indirect  0/rm32/EAX    .           .             .           .           .               .                 # push *EAX
+    # EAX = handle->address (payload)
+    8b/copy                         1/mod/*+disp8   0/rm32/EAX    .           .             .           .           4/disp8         .                 # copy *(EAX+4) to EAX
+    # push handle->address
+    50/push-EAX
+    # EAX = payload->alloc_id
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           .           .               .                 # copy *EAX to EAX
+    # if (EAX != handle->alloc_id) abort
+    39/compare                      1/mod/*+disp8   4/rm32/sib    4/base/ESP  4/index/none  .           0/r32/EAX   4/disp8         .                 # compare *(ESP+4) and EAX
+    75/jump-if-not-equal  $lookup:abort/disp8
+    # EAX = pop handle->address
+    58/pop-to-EAX
+    # discard handle->alloc_id
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # add 4
+    05/add-to-EAX  4/imm32
+    # - }
+    # - alternative consuming a second register {
+#?     # ECX = handle->alloc_id
+#?     8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+#?     # EAX = handle->address (payload)
+#?     8b/copy                         1/mod/*+disp8   0/rm32/EAX    .           .             .           0/r32/EAX   4/disp8         .                 # copy *(EAX+4) to EAX
+#?     # if (ECX != *EAX) abort
+#?     39/compare                      0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # compare *EAX and ECX
+#?     75/jump-if-not-equal  $lookup:abort/disp8
+#?     # add 4 to EAX
+#?     05/add-to-EAX  4/imm32
+    # - }
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+$lookup:abort:
+    # . _write(2/stderr, msg)
+    # . . push args
+    68/push  "lookup failed\n"/imm32
+    68/push  2/imm32/stderr
+    # . . call
+    e8/call  _write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . syscall(exit, 1)
+    bb/copy-to-EBX  1/imm32/exit-status
+    b8/copy-to-EAX  1/imm32/exit
+    cd/syscall  0x80/imm8
+
+test-lookup-success:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    # var heap/EBX : (address allocation-descriptor) = {0, 0}
+    68/push  0/imm32/limit
+    68/push  0/imm32/curr
+    89/copy                         3/mod/direct    3/rm32/EBX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBX
+    # heap = new-segment(512)
+    # . . push args
+    53/push-EBX
+    68/push  0x200/imm32
+    # . . call
+    e8/call  new-segment/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # var handle/ECX = {0, 0}
+    68/push  0/imm32/address
+    68/push  0/imm32/alloc-id
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # var old_top/EDX = heap->curr
+    8b/copy                         0/mod/indirect  3/rm32/EBX    .           .             .           2/r32/EDX   .               .                 # copy *EBX to EDX
+    # new(heap, 2, handle)
+    # . . push args
+    51/push-ECX
+    68/push  2/imm32/size
+    53/push-EBX
+    # . . call
+    e8/call  new/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # EAX = lookup(handle)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  lookup/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # EAX contains old top of heap, except skipping the alloc id in the payload
+    # . check-ints-equal(EAX, old_top+4, msg)
+    # . . push args
+    68/push  "F - test-lookup-success"/imm32
+    81          0/subop/add         3/mod/direct    2/rm32/EDX    .           .             .           .           .               4/imm32           # add to EDX
+    52/push-EDX
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # clean up
+    # . *Next-alloc-id = 1
+    c7          0/subop/copy        0/mod/indirect  5/rm32/.disp32            .             .           .     Next-alloc-id/disp32  1/imm32           # copy to *Next-alloc-id
+    # write(2/stderr, "lookup succeeded\n")
+    # . . push args
+    68/push  "lookup succeeded\n"/imm32
+    68/push  2/imm32/stderr
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . restore registers
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-lookup-failure:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # var heap/ESI : (address allocation-descriptor) = {0, 0}
+    68/push  0/imm32/limit
+    68/push  0/imm32/curr
+    89/copy                         3/mod/direct    6/rm32/ESI    .           .             .           4/r32/ESP   .               .                 # copy ESP to ESI
+    # heap = new-segment(512)
+    # . . push args
+    56/push-ESI
+    68/push  0x200/imm32
+    # . . call
+    e8/call  new-segment/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # var h1/ECX = {0, 0}
+    68/push  0/imm32/address
+    68/push  0/imm32/alloc-id
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # var old_top/EBX = heap->curr
+    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           3/r32/EBX   .               .                 # copy *ESI to EBX
+    # first allocation, to h1
+    # . new(heap, 2, h1)
+    # . . push args
+    51/push-ECX
+    68/push  2/imm32/size
+    56/push-ESI
+    # . . call
+    e8/call  new/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # reset heap->curr to mimic reclamation
+    89/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           3/r32/EBX   .               .                 # copy EBX to *ESI
+    # second allocation that returns the same address as the first
+    # var h2/EDX = {0, 0}
+    68/push  0/imm32/address
+    68/push  0/imm32/alloc-id
+    89/copy                         3/mod/direct    2/rm32/EDX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EDX
+    # . new(heap, 2, h2)
+    # . . push args
+    52/push-EDX
+    68/push  2/imm32/size
+    56/push-ESI
+    # . . call
+    e8/call  new/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # check-ints-equal(h1->address, h2->address, msg)
+    # . . push args
+    68/push  "F - test-lookup-failure"/imm32
+    ff          6/subop/push        1/mod/*+disp8   2/rm32/ECX    .           .             .           .           4/disp8         .                 # push *(EDX+4)
+    ff          6/subop/push        1/mod/*+disp8   1/rm32/ECX    .           .             .           .           4/disp8         .                 # push *(ECX+4)
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # lookup(h1) should crash
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  lookup/disp32
+    # should never get past this point
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # clean up
+    # . *Next-alloc-id = 1
+    c7          0/subop/copy        0/mod/indirect  5/rm32/.disp32            .             .           .     Next-alloc-id/disp32  1/imm32           # copy to *Next-alloc-id
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+== data
+
+# Monotonically increasing counter for calls to 'new'
+Next-alloc-id:
+    1/imm32
+
+# . . vim:nowrap:textwidth=0
diff --git a/apps/hex b/apps/hex
new file mode 100755
index 00000000..84575cfd
--- /dev/null
+++ b/apps/hex
Binary files differdiff --git a/apps/hex.subx b/apps/hex.subx
new file mode 100644
index 00000000..a24c5a2e
--- /dev/null
+++ b/apps/hex.subx
@@ -0,0 +1,1515 @@
+# Read a text file containing whitespace-separated pairs of ascii hex bytes
+# from stdin, and convert them into binary bytes (octets) on stdout. Ignore
+# comments between '#' and newline.
+#
+# To run (from the subx/ directory):
+#   $ ./subx translate *.subx apps/hex.subx -o apps/hex
+#   $ echo '80 81 82  # comment'  |./subx run apps/hex  |xxd -
+# Expected output:
+#   00000000: 8081 82
+#
+# Only hex bytes and comments are permitted. Outside of comments all words
+# must be exactly 2 characters long and contain only characters [0-9a-f]. No
+# uppercase hex.
+
+== code
+#   instruction                     effective address                                                   register    displacement    immediate
+# . op          subop               mod             rm32          base        index         scale       r32
+# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
+
+Entry:  # run tests if necessary, convert stdin if not
+    # initialize heap
+    # . Heap = new-segment(64KB)
+    # . . push args
+    68/push  Heap/imm32
+    68/push  0x10000/imm32/64KB
+    # . . call
+    e8/call  new-segment/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+
+    # . prolog
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # - if argc > 1 and argv[1] == "test", then return run_tests()
+    # . argc > 1
+    81          7/subop/compare     1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0/disp8         1/imm32           # compare *EBP
+    7e/jump-if-lesser-or-equal  $run-main/disp8
+    # . argv[1] == "test"
+    # . . push args
+    68/push  "test"/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  kernel-string-equal?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . check result
+    3d/compare-EAX-and  1/imm32
+    75/jump-if-not-equal  $run-main/disp8
+    # . run-tests()
+    e8/call  run-tests/disp32
+    8b/copy                         0/mod/indirect  5/rm32/.disp32            .             .           3/r32/EBX   Num-test-failures/disp32          # copy *Num-test-failures to EBX
+    eb/jump  $main:end/disp8
+$run-main:
+    # - otherwise convert stdin
+    # var ed/EAX : exit-descriptor
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # subtract from ESP
+    89/copy                         3/mod/direct    0/rm32/EAX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EAX
+    # configure ed to really exit()
+    # . ed->target = 0
+    c7          0/subop/copy        0/mod/direct    0/rm32/EAX    .           .             .           .           .               0/imm32           # copy to *EAX
+    # return convert(Stdin, 1/stdout, 2/stderr, ed)
+    # . . push args
+    50/push-EAX/ed
+    68/push  Stderr/imm32
+    68/push  Stdout/imm32
+    68/push  Stdin/imm32
+    # . . call
+    e8/call  convert/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
+    # . syscall(exit, 0)
+    bb/copy-to-EBX  0/imm32
+$main:end:
+    b8/copy-to-EAX  1/imm32/exit
+    cd/syscall  0x80/imm8
+
+# the main entry point
+convert:  # in : (address buffered-file), out : (address buffered-file), err : (address buffered-file), ed : (address exit-descriptor) -> <void>
+    # pseudocode:
+    #   while true
+    #     EAX = convert-next-octet(in, err, ed)
+    #     if (EAX == Eof) break
+    #     write-byte-buffered(out, AL)
+    #   flush(out)
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+$convert:loop:
+    # EAX = convert-next-octet(in, err, ed)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x14/disp8      .                 # push *(EBP+20)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x10/disp8      .                 # push *(EBP+16)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  convert-next-octet/disp32
+    # . . discard first 2 args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # if (EAX == Eof) break
+    3d/compare-EAX-and  0xffffffff/imm32/Eof
+    74/jump-if-equal  $convert:loop-end/disp8
+    # write-byte-buffered(out, AL)
+    # . . push args
+    50/push-EAX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write-byte-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # loop
+    eb/jump  $convert:loop/disp8
+$convert:loop-end:
+    # flush(out)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+$convert:end:
+    # . restore registers
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+# read bytes from 'in' until a sequence of two lowercase hex (0-9, a-f) bytes
+# skip spaces and newlines
+# on '#' skip bytes until newline
+# raise an error and abort on all other unexpected bytes
+# return in EAX an _octet_ containing the binary value of the two hex characters
+# return Eof on reaching end of file
+convert-next-octet:  # in : (address buffered-file), err : (address buffered-file), ed : (address exit-descriptor) -> byte-or-Eof/EAX
+    # pseudocode:
+    #   EAX = scan-next-byte(in, err, ed)
+    #   if (EAX == Eof) return
+    #   ECX = from-hex-char(EAX)
+    #   EAX = scan-next-byte(in, err, ed)
+    #   if (EAX == Eof) error("partial byte found.")
+    #   EAX = from-hex-char(EAX)
+    #   EAX = (ECX << 4) | EAX
+    #   return
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    51/push-ECX
+    # EAX = scan-next-byte(in, err, ed)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x10/disp8      .                 # push *(EBP+16)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  scan-next-byte/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # if (EAX == Eof) return
+    3d/compare-EAX-and  0xffffffff/imm32/Eof
+    74/jump-if-equal  $convert-next-octet:end/disp8
+    # EAX = from-hex-char(EAX)
+    e8/call from-hex-char/disp32
+    # ECX = EAX
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           0/r32/EAX   .               .                 # copy EAX to ECX
+    # EAX = scan-next-byte(in, err, ed)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x10/disp8      .                 # push *(EBP+16)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  scan-next-byte/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # if (EAX == Eof) error(ed, err, "partial byte found.")
+    3d/compare-EAX-and  0xffffffff/imm32/Eof
+    75/jump-if-not-equal  $convert-next-octet:convert/disp8
+    # . error-byte(ed, err, msg, '.')  # reusing error-byte to avoid creating _yet_ another helper
+    # . . push args
+    68/push  0x2e/imm32/period/dummy
+    68/push  "convert-next-octet: partial byte found"/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x10/disp8      .                 # push *(EBP+16)
+    # . . call
+    e8/call  error-byte/disp32  # never returns
+$convert-next-octet:convert:
+    # EAX = from-hex-char(EAX)
+    e8/call from-hex-char/disp32
+    # EAX = (ECX << 4) | EAX
+    # . ECX <<= 4
+    c1/shift    4/subop/left        3/mod/direct    1/rm32/ECX    .           .             .           .           .               4/imm8            # shift ECX left by 4 bits
+    # . EAX |= ECX
+    09/or                           3/mod/direct    0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # EAX = bitwise OR with ECX
+$convert-next-octet:end:
+    # . restore registers
+    59/pop-to-ECX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-next-octet:
+    # - check that the first two bytes of the input are assembled into the resulting octet
+    # This test uses exit-descriptors. Use EBP for setting up local variables.
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # clear all streams
+    # . clear-stream(_test-stream)
+    # . . push args
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-error-stream)
+    # . . push args
+    68/push  _test-error-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-error-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-error-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize '_test-stream' to "abc"
+    # . write(_test-stream, "abc")
+    # . . push args
+    68/push  "abc"/imm32
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # initialize exit-descriptor 'ed' for the call to 'convert-next-octet' below
+    # . var ed/ECX : exit-descriptor
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # subtract from ESP
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # . tailor-exit-descriptor(ed, 12)
+    # . . push args
+    68/push  0xc/imm32/nbytes-of-args-for-convert-next-octet
+    51/push-ECX/ed
+    # . . call
+    e8/call  tailor-exit-descriptor/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # EAX = convert-next-octet(_test-buffered-file, _test-error-buffered-file, ed)
+    # . . push args
+    51/push-ECX/ed
+    68/push  _test-error-buffered-file/imm32
+    68/push  _test-buffered-file/imm32
+    # . . call
+    e8/call  convert-next-octet/disp32
+    # registers except ESP may be clobbered at this point
+    # pop args to convert-next-octet
+    # . . discard first 2 args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . . restore ed
+    59/pop-to-ECX
+    # check that convert-next-octet didn't abort
+    # . check-ints-equal(ed->value, 0, msg)
+    # . . push args
+    68/push  "F - test-convert-next-octet: unexpected abort"/imm32
+    68/push  0/imm32
+    # . . push ed->value
+    ff          6/subop/push        1/mod/*+disp8   1/rm32/ECX    .           .             .           .           4/disp8         .                 # push *(ECX+4)
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # return if abort
+    81          7/subop/compare     1/mod/*+disp8   1/rm32/ECX    .           .             .           .           4/disp8         0/imm32           # compare *(ECX+4)
+    75/jump-if-not-equal  $test-convert-next-octet:end/disp8
+    # check-ints-equal(EAX, 0xab, msg)
+    # . . push args
+    68/push  "F - test-convert-next-octet"/imm32
+    68/push  0xab/imm32/ab
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-convert-next-octet:end:
+    # . epilog
+    # don't restore ESP from EBP; manually reclaim locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-next-octet-handles-Eof:
+    # - check that reaching end of file returns Eof
+    # This test uses exit-descriptors. Use EBP for setting up local variables.
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # clear all streams
+    # . clear-stream(_test-stream)
+    # . . push args
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-error-stream)
+    # . . push args
+    68/push  _test-error-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-error-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-error-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # don't initialize '_test-stream'
+    # initialize exit-descriptor 'ed' for the call to 'convert-next-octet' below
+    # . var ed/ECX : exit-descriptor
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # subtract from ESP
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # . tailor-exit-descriptor(ed, 12)
+    # . . push args
+    68/push  0xc/imm32/nbytes-of-args-for-convert-next-octet
+    51/push-ECX/ed
+    # . . call
+    e8/call  tailor-exit-descriptor/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # EAX = convert-next-octet(_test-buffered-file, _test-error-buffered-file, ed)
+    # . . push args
+    51/push-ECX/ed
+    68/push  _test-error-buffered-file/imm32
+    68/push  _test-buffered-file/imm32
+    # . . call
+    e8/call  convert-next-octet/disp32
+    # registers except ESP may be clobbered at this point
+    # pop args to convert-next-octet
+    # . . discard first 2 args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . . restore ed
+    59/pop-to-ECX
+    # check that convert-next-octet didn't abort
+    # . check-ints-equal(ed->value, 0, msg)
+    # . . push args
+    68/push  "F - test-convert-next-octet: unexpected abort"/imm32
+    68/push  0/imm32
+    # . . push ed->value
+    ff          6/subop/push        1/mod/*+disp8   1/rm32/ECX    .           .             .           .           4/disp8         .                 # push *(ECX+4)
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # return if abort
+    81          7/subop/compare     1/mod/*+disp8   1/rm32/ECX    .           .             .           .           4/disp8         0/imm32           # compare *(ECX+4)
+    75/jump-if-not-equal  $test-convert-next-octet-handles-Eof:end/disp8
+    # check-ints-equal(EAX, Eof, msg)
+    # . . push args
+    68/push  "F - test-convert-next-octet-handles-Eof"/imm32
+    68/push  0xffffffff/imm32/Eof
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-convert-next-octet-handles-Eof:end:
+    # . epilog
+    # don't restore ESP from EBP; manually reclaim locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-next-octet-aborts-on-single-hex-byte:
+    # - check that a single unaccompanied hex byte aborts
+    # This test uses exit-descriptors. Use EBP for setting up local variables.
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # clear all streams
+    # . clear-stream(_test-stream)
+    # . . push args
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-error-stream)
+    # . . push args
+    68/push  _test-error-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-error-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-error-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize '_test-stream' to "a"
+    # . write(_test-stream, "a")
+    # . . push args
+    68/push  "a"/imm32
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # initialize exit-descriptor 'ed' for the call to 'convert-next-octet' below
+    # . var ed/ECX : exit-descriptor
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # subtract from ESP
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # . tailor-exit-descriptor(ed, 12)
+    # . . push args
+    68/push  0xc/imm32/nbytes-of-args-for-convert-next-octet
+    51/push-ECX/ed
+    # . . call
+    e8/call  tailor-exit-descriptor/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # EAX = convert-next-octet(_test-buffered-file, _test-error-buffered-file, ed)
+    # . . push args
+    51/push-ECX/ed
+    68/push  _test-error-buffered-file/imm32
+    68/push  _test-buffered-file/imm32
+    # . . call
+    e8/call  convert-next-octet/disp32
+    # registers except ESP may be clobbered at this point
+    # pop args to convert-next-octet
+    # . . discard first 2 args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . . restore ed
+    59/pop-to-ECX
+    # check that convert-next-octet aborted
+    # . check-ints-equal(ed->value, 2, msg)
+    # . . push args
+    68/push  "F - test-convert-next-octet-aborts-on-single-hex-byte: unexpected abort"/imm32
+    68/push  2/imm32
+    # . . push ed->value
+    ff          6/subop/push        1/mod/*+disp8   1/rm32/ECX    .           .             .           .           4/disp8         .                 # push *(ECX+4)
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-convert-next-octet-aborts-on-single-hex-byte:end:
+    # . epilog
+    # don't restore ESP from EBP; manually reclaim locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    5d/pop-to-EBP
+    c3/return
+
+# read whitespace until a hex byte, and return it
+# return Eof if file ends without finding a hex byte
+# on '#' skip all bytes until newline
+# abort on any other byte
+scan-next-byte:  # in : (address buffered-file), err : (address buffered-file), ed : (address exit-descriptor) -> byte-or-Eof/EAX
+    # pseudocode:
+    #   while true
+    #     EAX = read-byte-buffered(in)
+    #     if (EAX == Eof) return EAX
+    #     if (is-hex-digit?(EAX)) return EAX
+    #     if (EAX == ' ' or '\t' or '\n') continue
+    #     if (EAX == '#') skip-until-newline(in)
+    #     else error-byte(ed, err, "invalid byte: " EAX)
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+$scan-next-byte:loop:
+    # EAX = read-byte-buffered(in)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  read-byte-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # if (EAX == Eof) return EAX
+    3d/compare-with-EAX  0xffffffff/imm32/Eof
+    74/jump-if-equal  $scan-next-byte:end/disp8
+    # if (is-hex-digit?(EAX)) return EAX
+    # . save EAX for now
+    50/push-EAX
+    # . is-hex-digit?(EAX)
+    # . . push args
+    50/push-EAX
+    # . . call
+    e8/call  is-hex-digit?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . compare with 'false'
+    3d/compare-with-EAX  0/imm32
+    # . restore EAX (does not affect flags)
+    58/pop-to-EAX
+    # . check whether to return
+    75/jump-if-not-equal  $scan-next-byte:end/disp8
+$scan-next-byte:check1:
+    # if (EAX == ' ') continue
+    3d/compare-EAX-and  0x20/imm32/space
+    74/jump-if-equal  $scan-next-byte:loop/disp8
+    # if (EAX == '\t') continue
+    3d/compare-EAX-and  9/imm32/tab
+    74/jump-if-equal  $scan-next-byte:loop/disp8
+    # if (EAX == '\n') continue
+    3d/compare-EAX-and  0xa/imm32/newline
+    74/jump-if-equal  $scan-next-byte:loop/disp8
+$scan-next-byte:check2:
+    # if (EAX == '#') skip-until-newline(in)
+    3d/compare-with-EAX  0x23/imm32
+    75/jump-if-not-equal  $scan-next-byte:check3/disp8
+    # . skip-until-newline(in)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  skip-until-newline/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    eb/jump  $scan-next-byte:loop/disp8
+$scan-next-byte:check3:
+    # otherwise error-byte(ed, err, msg, EAX)
+    # . . push args
+    50/push-EAX
+    68/push  "scan-next-byte: invalid byte"/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x10/disp8      .                 # push *(EBP+16)
+    # . . call
+    e8/call  error-byte/disp32  # never returns
+$scan-next-byte:end:
+    # . restore registers
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-scan-next-byte:
+    # - check that the first byte of the input is returned
+    # This test uses exit-descriptors. Use EBP for setting up local variables.
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # clear all streams
+    # . clear-stream(_test-stream)
+    # . . push args
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-error-stream)
+    # . . push args
+    68/push  _test-error-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-error-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-error-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize '_test-stream' to "abc"
+    # . write(_test-stream, "abc")
+    # . . push args
+    68/push  "abc"/imm32
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # initialize exit-descriptor 'ed' for the call to 'scan-next-byte' below
+    # . var ed/ECX : exit-descriptor
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # subtract from ESP
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # . tailor-exit-descriptor(ed, 12)
+    # . . push args
+    68/push  0xc/imm32/nbytes-of-args-for-scan-next-byte
+    51/push-ECX/ed
+    # . . call
+    e8/call  tailor-exit-descriptor/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # EAX = scan-next-byte(_test-buffered-file, _test-error-buffered-file, ed)
+    # . . push args
+    51/push-ECX/ed
+    68/push  _test-error-buffered-file/imm32
+    68/push  _test-buffered-file/imm32
+    # . . call
+    e8/call  scan-next-byte/disp32
+    # registers except ESP may be clobbered at this point
+    # pop args to scan-next-byte
+    # . . discard first 2 args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . . restore ed
+    59/pop-to-ECX
+    # check that scan-next-byte didn't abort
+    # . check-ints-equal(ed->value, 0, msg)
+    # . . push args
+    68/push  "F - test-scan-next-byte: unexpected abort"/imm32
+    68/push  0/imm32
+    # . . push ed->value
+    ff          6/subop/push        1/mod/*+disp8   1/rm32/ECX    .           .             .           .           4/disp8         .                 # push *(ECX+4)
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # return if abort
+    81          7/subop/compare     1/mod/*+disp8   1/rm32/ECX    .           .             .           .           4/disp8         0/imm32           # compare *(ECX+4)
+    75/jump-if-not-equal  $test-scan-next-byte:end/disp8
+    # check-ints-equal(EAX, 0x61/a, msg)
+    # . . push args
+    68/push  "F - test-scan-next-byte"/imm32
+    68/push  0x61/imm32/a
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-scan-next-byte:end:
+    # . epilog
+    # don't restore ESP from EBP; manually reclaim locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-scan-next-byte-skips-whitespace:
+    # - check that the first byte after whitespace is returned
+    # This test uses exit-descriptors. Use EBP for setting up local variables.
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # clear all streams
+    # . clear-stream(_test-stream)
+    # . . push args
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-error-stream)
+    # . . push args
+    68/push  _test-error-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-error-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-error-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize '_test-stream' to input with leading whitespace
+    # . write(_test-stream, text)
+    # . . push args
+    68/push  "  abc"/imm32
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # initialize exit-descriptor 'ed' for the call to 'scan-next-byte' below
+    # . var ed/ECX : exit-descriptor
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # subtract from ESP
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # . tailor-exit-descriptor(ed, 12)
+    # . . push args
+    68/push  0xc/imm32/nbytes-of-args-for-scan-next-byte
+    51/push-ECX/ed
+    # . . call
+    e8/call  tailor-exit-descriptor/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # EAX = scan-next-byte(_test-buffered-file, _test-error-buffered-file, ed)
+    # . . push args
+    51/push-ECX/ed
+    68/push  _test-error-buffered-file/imm32
+    68/push  _test-buffered-file/imm32
+    # . . call
+    e8/call  scan-next-byte/disp32
+    # registers except ESP may be clobbered at this point
+    # pop args to scan-next-byte
+    # . . discard first 2 args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . . restore ed
+    59/pop-to-ECX
+    # check that scan-next-byte didn't abort
+    # . check-ints-equal(ed->value, 0, msg)
+    # . . push args
+    68/push  "F - test-scan-next-byte-skips-whitespace: unexpected abort"/imm32
+    68/push  0/imm32
+    # . . push ed->value
+    ff          6/subop/push        1/mod/*+disp8   1/rm32/ECX    .           .             .           .           4/disp8         .                 # push *(ECX+4)
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # return if abort
+    81          7/subop/compare     1/mod/*+disp8   1/rm32/ECX    .           .             .           .           4/disp8         0/imm32           # compare *(ECX+4)
+    75/jump-if-not-equal  $test-scan-next-byte-skips-whitespace:end/disp8
+    # check-ints-equal(EAX, 0x61/a, msg)
+    # . . push args
+    68/push  "F - test-scan-next-byte-skips-whitespace"/imm32
+    68/push  0x61/imm32/a
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-scan-next-byte-skips-whitespace:end:
+    # . epilog
+    # don't restore ESP from EBP; manually reclaim locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-scan-next-byte-skips-comment:
+    # - check that the first byte after a comment (and newline) is returned
+    # This test uses exit-descriptors. Use EBP for setting up local variables.
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # clear all streams
+    # . clear-stream(_test-stream)
+    # . . push args
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-error-stream)
+    # . . push args
+    68/push  _test-error-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-error-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-error-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize '_test-stream' to input with leading comment
+    # . write(_test-stream, comment)
+    # . . push args
+    68/push  "#x\n"/imm32
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-stream, real text)
+    # . . push args
+    68/push  "ab"/imm32
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # initialize exit-descriptor 'ed' for the call to 'scan-next-byte' below
+    # . var ed/ECX : exit-descriptor
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # subtract from ESP
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # . tailor-exit-descriptor(ed, 12)
+    # . . push args
+    68/push  0xc/imm32/nbytes-of-args-for-scan-next-byte
+    51/push-ECX/ed
+    # . . call
+    e8/call  tailor-exit-descriptor/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # EAX = scan-next-byte(_test-buffered-file, _test-error-buffered-file, ed)
+    # . . push args
+    51/push-ECX/ed
+    68/push  _test-error-buffered-file/imm32
+    68/push  _test-buffered-file/imm32
+    # . . call
+    e8/call  scan-next-byte/disp32
+    # registers except ESP may be clobbered at this point
+    # pop args to scan-next-byte
+    # . . discard first 2 args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . . restore ed
+    59/pop-to-ECX
+    # check that scan-next-byte didn't abort
+    # . check-ints-equal(ed->value, 0, msg)
+    # . . push args
+    68/push  "F - test-scan-next-byte-skips-comment: unexpected abort"/imm32
+    68/push  0/imm32
+    # . . push ed->value
+    ff          6/subop/push        1/mod/*+disp8   1/rm32/ECX    .           .             .           .           4/disp8         .                 # push *(ECX+4)
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # return if abort
+    81          7/subop/compare     1/mod/*+disp8   1/rm32/ECX    .           .             .           .           4/disp8         0/imm32           # compare *(ECX+4)
+    75/jump-if-not-equal  $test-scan-next-byte-skips-comment:end/disp8
+    # check-ints-equal(EAX, 0x61/a, msg)
+    # . . push args
+    68/push  "F - test-scan-next-byte-skips-comment"/imm32
+    68/push  0x61/imm32/a
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-scan-next-byte-skips-comment:end:
+    # . epilog
+    # don't restore ESP from EBP; manually reclaim locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-scan-next-byte-skips-comment-and-whitespace:
+    # - check that the first byte after a comment and any further whitespace is returned
+    # This test uses exit-descriptors. Use EBP for setting up local variables.
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # clear all streams
+    # . clear-stream(_test-stream)
+    # . . push args
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-error-stream)
+    # . . push args
+    68/push  _test-error-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-error-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-error-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize '_test-stream' to input with leading comment and more whitespace after newline
+    # . write(_test-stream, comment)
+    # . . push args
+    68/push  "#x\n"/imm32
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-stream, real text)
+    # . . push args
+    68/push  " ab"/imm32
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # initialize exit-descriptor 'ed' for the call to 'scan-next-byte' below
+    # . var ed/ECX : exit-descriptor
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # subtract from ESP
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # . tailor-exit-descriptor(ed, 12)
+    # . . push args
+    68/push  0xc/imm32/nbytes-of-args-for-scan-next-byte
+    51/push-ECX/ed
+    # . . call
+    e8/call  tailor-exit-descriptor/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # EAX = scan-next-byte(_test-buffered-file, _test-error-buffered-file, ed)
+    # . . push args
+    51/push-ECX/ed
+    68/push  _test-error-buffered-file/imm32
+    68/push  _test-buffered-file/imm32
+    # . . call
+    e8/call  scan-next-byte/disp32
+    # registers except ESP may be clobbered at this point
+    # pop args to scan-next-byte
+    # . . discard first 2 args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . . restore ed
+    59/pop-to-ECX
+    # check that scan-next-byte didn't abort
+    # . check-ints-equal(ed->value, 0, msg)
+    # . . push args
+    68/push  "F - test-scan-next-byte-skips-comment-and-whitespace: unexpected abort"/imm32
+    68/push  0/imm32
+    # . . push ed->value
+    ff          6/subop/push        1/mod/*+disp8   1/rm32/ECX    .           .             .           .           4/disp8         .                 # push *(ECX+4)
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # return if abort
+    81          7/subop/compare     1/mod/*+disp8   1/rm32/ECX    .           .             .           .           4/disp8         0/imm32           # compare *(ECX+4)
+    75/jump-if-not-equal  $test-scan-next-byte-skips-comment-and-whitespace:end/disp8
+    # check-ints-equal(EAX, 0x61/a, msg)
+    # . . push args
+    68/push  "F - test-scan-next-byte-skips-comment-and-whitespace"/imm32
+    68/push  0x61/imm32/a
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-scan-next-byte-skips-comment-and-whitespace:end:
+    # . epilog
+    # don't restore ESP from EBP; manually reclaim locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-scan-next-byte-skips-whitespace-and-comment:
+    # - check that the first byte after any whitespace and comments is returned
+    # This test uses exit-descriptors. Use EBP for setting up local variables.
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # clear all streams
+    # . clear-stream(_test-stream)
+    # . . push args
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-error-stream)
+    # . . push args
+    68/push  _test-error-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-error-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-error-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize '_test-stream' to input with leading whitespace and comment
+    # . write(_test-stream, comment)
+    # . . push args
+    68/push  " #x\n"/imm32
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-stream, real text)
+    # . . push args
+    68/push  "ab"/imm32
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # initialize exit-descriptor 'ed' for the call to 'scan-next-byte' below
+    # . var ed/ECX : exit-descriptor
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # subtract from ESP
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # . tailor-exit-descriptor(ed, 12)
+    # . . push args
+    68/push  0xc/imm32/nbytes-of-args-for-scan-next-byte
+    51/push-ECX/ed
+    # . . call
+    e8/call  tailor-exit-descriptor/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # EAX = scan-next-byte(_test-buffered-file, _test-error-buffered-file, ed)
+    # . . push args
+    51/push-ECX/ed
+    68/push  _test-error-buffered-file/imm32
+    68/push  _test-buffered-file/imm32
+    # . . call
+    e8/call  scan-next-byte/disp32
+    # registers except ESP may be clobbered at this point
+    # pop args to scan-next-byte
+    # . . discard first 2 args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . . restore ed
+    59/pop-to-ECX
+    # check that scan-next-byte didn't abort
+    # . check-ints-equal(ed->value, 0, msg)
+    # . . push args
+    68/push  "F - test-scan-next-byte-skips-whitespace-and-comment: unexpected abort"/imm32
+    68/push  0/imm32
+    # . . push ed->value
+    ff          6/subop/push        1/mod/*+disp8   1/rm32/ECX    .           .             .           .           4/disp8         .                 # push *(ECX+4)
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # return if abort
+    81          7/subop/compare     1/mod/*+disp8   1/rm32/ECX    .           .             .           .           4/disp8         0/imm32           # compare *(ECX+4)
+    75/jump-if-not-equal  $test-scan-next-byte-skips-whitespace-and-comment:end/disp8
+    # check-ints-equal(EAX, 0x61/a, msg)
+    # . . push args
+    68/push  "F - test-scan-next-byte-skips-whitespace-and-comment"/imm32
+    68/push  0x61/imm32/a
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-scan-next-byte-skips-whitespace-and-comment:end:
+    # . epilog
+    # don't restore ESP from EBP; manually reclaim locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-scan-next-byte-reads-final-byte:
+    # - check that the final byte in input is returned
+    # This test uses exit-descriptors. Use EBP for setting up local variables.
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # clear all streams
+    # . clear-stream(_test-stream)
+    # . . push args
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-error-stream)
+    # . . push args
+    68/push  _test-error-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-error-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-error-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize '_test-stream' to input with single character
+    # . write(_test-stream, character)
+    # . . push args
+    68/push  "a"/imm32
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # initialize exit-descriptor 'ed' for the call to 'scan-next-byte' below
+    # . var ed/ECX : exit-descriptor
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # subtract from ESP
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # . tailor-exit-descriptor(ed, 12)
+    # . . push args
+    68/push  0xc/imm32/nbytes-of-args-for-scan-next-byte
+    51/push-ECX/ed
+    # . . call
+    e8/call  tailor-exit-descriptor/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # EAX = scan-next-byte(_test-buffered-file, _test-error-buffered-file, ed)
+    # . . push args
+    51/push-ECX/ed
+    68/push  _test-error-buffered-file/imm32
+    68/push  _test-buffered-file/imm32
+    # . . call
+    e8/call  scan-next-byte/disp32
+    # registers except ESP may be clobbered at this point
+    # pop args to scan-next-byte
+    # . . discard first 2 args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . . restore ed
+    59/pop-to-ECX
+    # check that scan-next-byte didn't abort
+    # . check-ints-equal(ed->value, 0, msg)
+    # . . push args
+    68/push  "F - test-scan-next-byte-reads-final-byte: unexpected abort"/imm32
+    68/push  0/imm32
+    # . . push ed->value
+    ff          6/subop/push        1/mod/*+disp8   1/rm32/ECX    .           .             .           .           4/disp8         .                 # push *(ECX+4)
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # return if abort
+    81          7/subop/compare     1/mod/*+disp8   1/rm32/ECX    .           .             .           .           4/disp8         0/imm32           # compare *(ECX+4)
+    75/jump-if-not-equal  $test-scan-next-byte-reads-final-byte:end/disp8
+    # check-ints-equal(EAX, 0x61/a, msg)
+    # . . push args
+    68/push  "F - test-scan-next-byte-reads-final-byte"/imm32
+    68/push  0x61/imm32/a
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-scan-next-byte-reads-final-byte:end:
+    # . epilog
+    # don't restore ESP from EBP; manually reclaim locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-scan-next-byte-handles-Eof:
+    # - check that the right sentinel value is returned when there's no data remaining to be read
+    # This test uses exit-descriptors. Use EBP for setting up local variables.
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # clear all streams
+    # . clear-stream(_test-stream)
+    # . . push args
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-error-stream)
+    # . . push args
+    68/push  _test-error-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-error-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-error-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # leave '_test-stream' empty
+    # initialize exit-descriptor 'ed' for the call to 'scan-next-byte' below
+    # . var ed/ECX : exit-descriptor
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # subtract from ESP
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # . tailor-exit-descriptor(ed, 12)
+    # . . push args
+    68/push  0xc/imm32/nbytes-of-args-for-scan-next-byte
+    51/push-ECX/ed
+    # . . call
+    e8/call  tailor-exit-descriptor/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # EAX = scan-next-byte(_test-buffered-file, _test-error-buffered-file, ed)
+    # . . push args
+    51/push-ECX/ed
+    68/push  _test-error-buffered-file/imm32
+    68/push  _test-buffered-file/imm32
+    # . . call
+    e8/call  scan-next-byte/disp32
+    # registers except ESP may be clobbered at this point
+    # pop args to scan-next-byte
+    # . . discard first 2 args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . . restore ed
+    59/pop-to-ECX
+    # check that scan-next-byte didn't abort
+    # . check-ints-equal(ed->value, 0, msg)
+    # . . push args
+    68/push  "F - test-scan-next-byte-handles-Eof: unexpected abort"/imm32
+    68/push  0/imm32
+    # . . push ed->value
+    ff          6/subop/push        1/mod/*+disp8   1/rm32/ECX    .           .             .           .           4/disp8         .                 # push *(ECX+4)
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # return if abort
+    81          7/subop/compare     1/mod/*+disp8   1/rm32/ECX    .           .             .           .           4/disp8         0/imm32           # compare *(ECX+4)
+    75/jump-if-not-equal  $test-scan-next-byte-handles-Eof:end/disp8
+    # check-ints-equal(EAX, Eof, msg)
+    # . . push args
+    68/push  "F - test-scan-next-byte-handles-Eof"/imm32
+    68/push  0xffffffff/imm32/Eof
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-scan-next-byte-handles-Eof:end:
+    # . epilog
+    # don't restore ESP from EBP; manually reclaim locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-scan-next-byte-aborts-on-invalid-byte:
+    # - check that the a bad byte immediately aborts
+    # This test uses exit-descriptors. Use EBP for setting up local variables.
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # clear all streams
+    # . clear-stream(_test-stream)
+    # . . push args
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-error-stream)
+    # . . push args
+    68/push  _test-error-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-error-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-error-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize '_test-stream' to "x"
+    # . write(_test-stream, "x")
+    # . . push args
+    68/push  "x"/imm32
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # initialize exit-descriptor 'ed' for the call to 'scan-next-byte' below
+    # . var ed/ECX : exit-descriptor
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # subtract from ESP
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # . tailor-exit-descriptor(ed, 12)
+    # . . push args
+    68/push  0xc/imm32/nbytes-of-args-for-scan-next-byte
+    51/push-ECX/ed
+    # . . call
+    e8/call  tailor-exit-descriptor/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # EAX = scan-next-byte(_test-buffered-file, _test-error-buffered-file, ed)
+    # . . push args
+    51/push-ECX/ed
+    68/push  _test-error-buffered-file/imm32
+    68/push  _test-buffered-file/imm32
+    # . . call
+    e8/call  scan-next-byte/disp32
+    # registers except ESP may be clobbered at this point
+    # pop args to scan-next-byte
+    # . . discard first 2 args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . . restore ed
+    59/pop-to-ECX
+    # check that scan-next-byte aborted
+    # . check-ints-equal(ed->value, 2, msg)
+    # . . push args
+    68/push  "F - test-scan-next-byte-aborts-on-invalid-byte"/imm32
+    68/push  2/imm32
+    # . . push ed->value
+    ff          6/subop/push        1/mod/*+disp8   1/rm32/ECX    .           .             .           .           4/disp8         .                 # push *(ECX+4)
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-scan-next-byte-aborts-on-invalid-byte:end:
+    # . epilog
+    # don't restore ESP from EBP; manually reclaim locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    5d/pop-to-EBP
+    c3/return
+
+skip-until-newline:  # in : (address buffered-file) -> <void>
+    # pseudocode:
+    #   push EAX
+    #   while true
+    #     EAX = read-byte-buffered(in)
+    #     if (EAX == Eof) break
+    #     if (EAX == 0x0a) break
+    #   pop EAX
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+$skip-until-newline:loop:
+    # . EAX = read-byte-buffered(in)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  read-byte-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . if (EAX == Eof) break
+    3d/compare-EAX-and  0xffffffff/imm32/Eof
+    74/jump-if-equal  $skip-until-newline:end/disp8
+    # . if (EAX != 0xa/newline) loop
+    3d/compare-EAX-and  0xa/imm32/newline
+    75/jump-if-not-equal  $skip-until-newline:loop/disp8
+$skip-until-newline:end:
+    # . restore registers
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-skip-until-newline:
+    # - check that the read pointer points after the newline
+    # setup
+    # . clear-stream(_test-stream)
+    # . . push args
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize '_test-stream' to "abc\nde"
+    # . write(_test-stream, "abc")
+    # . . push args
+    68/push  "abc\n"/imm32
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-stream, "de")
+    # . . push args
+    68/push  "de"/imm32
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # skip-until-newline(_test-buffered-file)
+    # . . push args
+    68/push  _test-buffered-file/imm32
+    # . . call
+    e8/call  skip-until-newline/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-ints-equal(_test-buffered-file->read, 4, msg)
+    # . . push args
+    68/push  "F - test-skip-until-newline"/imm32
+    68/push  4/imm32
+    b8/copy-to-EAX  _test-buffered-file/imm32
+    ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           8/disp8         .                 # push *(EAX+8)
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . end
+    c3/return
+
+== data
+
+_test-error-stream:
+    # current write index
+    0/imm32
+    # current read index
+    0/imm32
+    # line
+    0x80/imm32  # 128 bytes
+    # data (8 lines x 16 bytes/line)
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+
+# a test buffered file for _test-error-stream
+_test-error-buffered-file:
+    # file descriptor or (address stream)
+    _test-error-stream/imm32
+    # current write index
+    0/imm32
+    # current read index
+    0/imm32
+    # length
+    6/imm32
+    # data
+    00 00 00 00 00 00  # 6 bytes
+
+# . . vim:nowrap:textwidth=0
diff --git a/apps/pack b/apps/pack
new file mode 100755
index 00000000..720ba3ea
--- /dev/null
+++ b/apps/pack
Binary files differdiff --git a/apps/pack.subx b/apps/pack.subx
new file mode 100644
index 00000000..61a837ba
--- /dev/null
+++ b/apps/pack.subx
@@ -0,0 +1,5986 @@
+# Read a text file of SubX instructions from stdin, and convert it into a list
+# of whitespace-separated ascii hex bytes on stdout. Label definitions and
+# uses are left untouched.
+#
+# To run (from the subx/ directory):
+#   $ ./subx translate *.subx apps/pack.subx -o apps/pack
+#   $ echo '05/add-to-EAX 0x20/imm32'  |./subx run apps/pack
+# Expected output:
+#   05 20 00 00 00  # 05/add-to-EAX 0x20/imm32
+# The original instruction gets included as a comment at the end of each
+# converted line.
+#
+# There's zero error-checking. For now we assume the input program is valid.
+# We'll continue to rely on the C++ version for error messages.
+
+== code
+#   instruction                     effective address                                                   register    displacement    immediate
+# . op          subop               mod             rm32          base        index         scale       r32
+# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
+
+Entry:  # run tests if necessary, convert stdin if not
+    # initialize heap
+    # . Heap = new-segment(64KB)
+    # . . push args
+    68/push  Heap/imm32
+    68/push  0x10000/imm32/64KB
+    # . . call
+    e8/call  new-segment/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+
+    # . prolog
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # - if argc > 1 and argv[1] == "test", then return run_tests()
+    # . argc > 1
+    81          7/subop/compare     1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0/disp8         1/imm32           # compare *EBP
+    7e/jump-if-lesser-or-equal  $run-main/disp8
+    # . argv[1] == "test"
+    # . . push args
+    68/push  "test"/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  kernel-string-equal?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . check result
+    3d/compare-EAX-and  1/imm32
+    75/jump-if-not-equal  $run-main/disp8
+    # . run-tests()
+    e8/call  run-tests/disp32
+    8b/copy                         0/mod/indirect  5/rm32/.disp32            .             .           3/r32/EBX   Num-test-failures/disp32          # copy *Num-test-failures to EBX
+    eb/jump  $main:end/disp8
+$run-main:
+    # - otherwise convert stdin
+    # var ed/EAX : exit-descriptor
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # subtract from ESP
+    89/copy                         3/mod/direct    0/rm32/EAX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EAX
+    # configure ed to really exit()
+    # . ed->target = 0
+    c7          0/subop/copy        0/mod/direct    0/rm32/EAX    .           .             .           .           .               0/imm32           # copy to *EAX
+    # return convert(Stdin, 1/stdout, 2/stderr, ed)
+    # . . push args
+    50/push-EAX/ed
+    68/push  Stderr/imm32
+    68/push  Stdout/imm32
+    68/push  Stdin/imm32
+    # . . call
+    e8/call  convert/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
+    # . syscall(exit, 0)
+    bb/copy-to-EBX  0/imm32
+$main:end:
+    b8/copy-to-EAX  1/imm32/exit
+    cd/syscall  0x80/imm8
+
+# - big picture
+# We'll operate on each line/instruction in isolation. That way we only need to
+# allocate memory for converting a single instruction.
+#
+# To pack an entire file, convert every segment in it
+# To convert a code segment, convert every instruction (line) until the next segment header
+# To convert a non-data segment, convert every word until the next segment header
+#
+# primary state: line
+#   stream of 512 bytes; abort if it ever overflows
+
+# conceptual hierarchy within a line:
+#   line = words separated by ' ', maybe followed by comment starting with '#'
+#   word = datum until '/', then 0 or more metadata separated by '/'
+#
+# we won't bother saving the internal structure of lines; reparsing should be cheap using three primitives:
+#   next-token(stream, delim char) -> slice (start, end pointers)
+#   next-token-from-slice(start, end, delim char) -> slice
+#   slice-equal?(slice, string)
+
+convert:  # in : (address buffered-file), out : (address buffered-file) -> <void>
+    # pseudocode:
+    #   var line = new-stream(512, 1)
+    #   var in-code? = false
+    #   while true
+    #     clear-stream(line)
+    #     read-line-buffered(in, line)
+    #     if (line->write == 0) break             # end of file
+    #     var word-slice = next-word(line)
+    #     if slice-empty?(word-slice)             # whitespace
+    #       write-stream-data(out, line)
+    #     else if (slice-equal?(word-slice, "=="))
+    #       word-slice = next-word(line)
+    #       in-code? = slice-equal?(word-slice, "code")
+    #       write-stream-data(out, line)
+    #     else if (in-code?)
+    #       rewind-stream(line)
+    #       convert-instruction(line, out)
+    #     else
+    #       rewind-stream(line)
+    #       convert-data(line, out)
+    #   flush(out)
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+    51/push-ECX
+    52/push-EDX
+    53/push-EBX
+    # var line/ECX : (address stream byte) = stream(512)
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x200/imm32       # subtract from ESP
+    68/push  0x200/imm32/length
+    68/push  0/imm32/read
+    68/push  0/imm32/write
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # var word-slice/EDX = {0, 0}
+    68/push  0/imm32/end
+    68/push  0/imm32/start
+    89/copy                         3/mod/direct    2/rm32/EDX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EDX
+    # var in-code?/EBX = false
+    31/xor                          3/mod/direct    3/rm32/EBX    .           .             .           3/r32/EBX   .               .                 # clear EBX
+$convert:loop:
+    # clear-stream(line)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # read-line-buffered(in, line)
+    # . . push args
+    51/push-ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  read-line-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+$convert:check0:
+    # if (line->write == 0) break
+    81          7/subop/compare     0/mod/indirect  1/rm32/ECX    .           .             .           .           .               0/imm32           # compare *ECX
+    0f 84/jump-if-equal  $convert:break/disp32
+#?     # dump line {{{
+#?     # . write(2/stderr, "LL: ")
+#?     # . . push args
+#?     68/push  "LL: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, line)
+#?     # . . push args
+#?     51/push-ECX
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # next-word(line, word-slice)
+    # . . push args
+    52/push-EDX
+    51/push-ECX
+    # . . call
+    e8/call  next-word/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+$convert:check1:
+    # if (slice-empty?(word-slice)) write-stream-data(out, line)
+    # . EAX = slice-empty?(word-slice)
+    # . . push args
+    52/push-EDX
+    # . . call
+    e8/call  slice-empty?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . if (EAX != 0) write-stream-data(out, line)
+    3d/compare-EAX-and  0/imm32
+    0f 85/jump-if-not-equal  $convert:pass-through/disp32
+$convert:check2:
+#?     # dump word-slice {{{
+#?     # . write(2/stderr, "AA: ")
+#?     # . . push args
+#?     68/push  "AA: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . clear-stream(Stderr+4)
+#?     # . . push args
+#?     b8/copy-to-EAX  Stderr/imm32
+#?     05/add-to-EAX  4/imm32
+#?     50/push-EAX
+#?     # . . call
+#?     e8/call  clear-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . write-slice-buffered(Stderr, word-slice)
+#?     # . . push args
+#?     52/push-EDX
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  write-slice-buffered/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . flush(Stderr)
+#?     # . . push args
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  flush/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # if (!slice-equal?(word-slice, "==")) goto next check
+    # . EAX = slice-equal?(word-slice, "==")
+    # . . push args
+    68/push  "=="/imm32
+    52/push-EDX
+    # . . call
+    e8/call  slice-equal?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX == 0) goto check3
+    3d/compare-EAX-and  0/imm32
+    0f 84/jump-if-equal  $convert:check3/disp32
+    # word-slice = next-word(line)
+    # . . push args
+    52/push-EDX
+    51/push-ECX
+    # . . call
+    e8/call  next-word/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # dump segment name {{{
+#?     # . write(2/stderr, "AA: ")
+#?     # . . push args
+#?     68/push  "AA: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . clear-stream(Stderr+4)
+#?     # . . push args
+#?     b8/copy-to-EAX  Stderr/imm32
+#?     05/add-to-EAX  4/imm32
+#?     50/push-EAX
+#?     # . . call
+#?     e8/call  clear-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . write-slice-buffered(Stderr, word-slice)
+#?     # . . push args
+#?     52/push-EDX
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  write-slice-buffered/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . flush(Stderr)
+#?     # . . push args
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  flush/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # in-code? = slice-equal?(word-slice, "code")
+    # . . push args
+    68/push  "code"/imm32
+    52/push-EDX
+    # . . call
+    e8/call  slice-equal?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . . in-code? = EAX
+    89/copy                         3/mod/direct    3/rm32/EBX    .           .             .           0/r32/EAX   .               .                 # copy EAX to EBX
+    # write-stream-data(out, line)
+    eb/jump  $convert:pass-through/disp8
+$convert:check3:
+    # else rewind-stream(line)
+    # . rewind-stream(line)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  rewind-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # if (in-code? != 0) convert-instruction(line, out)
+    81          7/subop/compare     3/mod/direct    3/rm32/EBX    .           .             .           .           .               0/imm32           # compare EBX
+    74/jump-if-equal  $convert:data/disp8
+$convert:code:
+    # . convert-instruction(line, out)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    51/push-ECX
+    # . . call
+    e8/call  convert-instruction/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . loop
+    e9/jump  $convert:loop/disp32
+$convert:data:
+    # else convert-data(line, out)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    51/push-ECX
+    # . . call
+    e8/call  convert-data/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . loop
+    e9/jump  $convert:loop/disp32
+$convert:pass-through:
+    # write-stream-data(out, line)
+    # . . push args
+    51/push-ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write-stream-data/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . loop
+    e9/jump  $convert:loop/disp32
+$convert:break:
+    # flush(out)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+$convert:end:
+    # . reclaim locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x214/imm32       # add to ESP
+    # . restore registers
+    5b/pop-to-EBX
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-passes-empty-lines-through:
+    # if a line is empty, pass it along unchanged
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-input-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-input-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # write nothing to input
+    # convert(_test-input-buffered-file, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-buffered-file/imm32
+    # . . call
+    e8/call  convert/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check that the line just passed through
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . check-stream-equal(_test-output-stream, "", msg)
+    # . . push args
+    68/push  "F - test-convert-passes-empty-lines-through"/imm32
+    68/push  ""/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-passes-lines-with-just-whitespace-through:
+    # if a line is empty, pass it along unchanged
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-input-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-input-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "    ")
+    # . . push args
+    68/push  "    "/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert(_test-input-buffered-file, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-buffered-file/imm32
+    # . . call
+    e8/call  convert/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check that the line just passed through
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "    ", msg)
+    # . . push args
+    68/push  "F - test-convert-passes-with-just-whitespace-through"/imm32
+    68/push  "    "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-passes-segment-headers-through:
+    # if a line starts with '==', pass it along unchanged
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-input-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-input-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "== abcd 0x1")
+    # . . push args
+    68/push  "== abcd 0x1"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert(_test-input-buffered-file, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-buffered-file/imm32
+    # . . call
+    e8/call  convert/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check that the line just passed through
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . check-stream-equal(_test-output-stream, "== abcd 0x1", msg)
+    # . . push args
+    68/push  "F - test-convert-passes-segment-headers-through"/imm32
+    68/push  "== abcd 0x1"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-in-data-segment:
+    # correctly process lines in the data segment
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-input-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-input-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    #   == code 0x1
+    #   == data 0x2
+    #   3 4/imm32
+    # . write(_test-input-stream, "== code 0x1")
+    # . . push args
+    68/push  "== code 0x1\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "== data 0x2\n")
+    # . . push args
+    68/push  "== data 0x2\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "3 4/imm32\n")
+    # . . push args
+    68/push  "3 4/imm32\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert(_test-input-buffered-file, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-buffered-file/imm32
+    # . . call
+    e8/call  convert/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check output
+#?     # debug print {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "== code 0x1", msg)
+    # . . push args
+    68/push  "F - test-convert-in-data-segment/0"/imm32
+    68/push  "== code 0x1"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "== data 0x2", msg)
+    # . . push args
+    68/push  "F - test-convert-in-data-segment/1"/imm32
+    68/push  "== data 0x2"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "03 04 00 00 00 ", msg)
+    # . . push args
+    68/push  "F - test-convert-in-data-segment/2"/imm32
+    68/push  "03 04 00 00 00 "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-code-and-data-segments:
+    # correctly process lines in both code and data segments
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-input-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-input-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    #   == code 0x1
+    #   e8/call 20/disp32
+    #   68/push 0x20/imm8
+    #   == data 0x2
+    #   3 4/imm32
+    # . write(_test-input-stream, "== code 0x1\n")
+    # . . push args
+    68/push  "== code 0x1\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "e8/call 20/disp32\n")
+    # . . push args
+    68/push  "e8/call 20/disp32\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "68/push 0x20/imm8\n")
+    # . . push args
+    68/push  "68/push 0x20/imm8\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "== data 0x2\n")
+    # . . push args
+    68/push  "== data 0x2\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "3 4/imm32\n")
+    # . . push args
+    68/push  "3 4/imm32\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert(_test-input-buffered-file, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-buffered-file/imm32
+    # . . call
+    e8/call  convert/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check output
+    #   == code 0x1
+    #   e8 20 00 00 00  # e8/call 20/disp32
+    #   68 20  # 68/push 0x20/imm8
+    #   == data 0x2
+    #   03 04 00 00 00
+#?     # debug print {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "== code 0x1", msg)
+    # . . push args
+    68/push  "F - test-convert-code-and-data-segments/0"/imm32
+    68/push  "== code 0x1"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "e8 20 00 00 00  # e8/call 20/disp32", msg)
+    # . . push args
+    68/push  "F - test-convert-code-and-data-segments/1"/imm32
+    68/push  "e8 20 00 00 00  # e8/call 20/disp32"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "68 20  # 68/push 0x20/imm8", msg)
+    # . . push args
+    68/push  "F - test-convert-code-and-data-segments/2"/imm32
+    68/push  "68 20  # 68/push 0x20/imm8"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "== data 0x2", msg)
+    # . . push args
+    68/push  "F - test-convert-code-and-data-segments/3"/imm32
+    68/push  "== data 0x2"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "03 04 00 00 00 ", msg)
+    # . . push args
+    68/push  "F - test-convert-code-and-data-segments/4"/imm32
+    68/push  "03 04 00 00 00 "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+convert-data:  # line : (address stream byte), out : (address buffered-file) -> <void>
+    # pseudocode:
+    #   var word-slice = {0, 0}
+    #   while true
+    #     word-slice = next-word(line)
+    #     if slice-empty?(word-slice)                 # end of file (maybe including trailing whitespace)
+    #       break  # skip emitting some whitespace
+    #     if slice-starts-with?(word-slice, "#")      # comment
+    #       write-slice-buffered(out, word-slice)
+    #       return
+    #     if slice-ends-with?(word-slice, ":")        # label
+    #       write-stream-data(out, line)
+    #       return
+    #     if has-metadata?(word-slice, "imm32")
+    #       emit(out, word-slice, 4)
+    #     # disp32 is not permitted in data segments, and anything else is only a byte long
+    #     else
+    #       emit(out, word-slice, 1)
+    #   write-buffered(out, "\n")
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+    51/push-ECX
+    52/push-EDX
+    # var word-slice/ECX = {0, 0}
+    68/push  0/imm32/end
+    68/push  0/imm32/start
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+#?     # dump line {{{
+#?     # . write(2/stderr, "LL: ")
+#?     # . . push args
+#?     68/push  "LL: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # write-stream(2/stderr, line)
+#?     # . . push args
+#?     ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+$convert-data:loop:
+    # next-word(line, word-slice)
+    # . . push args
+    51/push-ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  next-word/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # dump word-slice {{{
+#?     # . write(2/stderr, "AA: ")
+#?     # . . push args
+#?     68/push  "AA: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . clear-stream(Stderr+4)
+#?     # . . push args
+#?     b8/copy-to-EAX  Stderr/imm32
+#?     05/add-to-EAX  4/imm32
+#?     50/push-EAX
+#?     # . . call
+#?     e8/call  clear-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . write-slice-buffered(Stderr, word-slice)
+#?     # . . push args
+#?     51/push-ECX
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  write-slice-buffered/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . flush(Stderr)
+#?     # . . push args
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  flush/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+$convert-data:check0:
+    # if (slice-empty?(word-slice)) break
+    # . EAX = slice-empty?(word-slice)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  slice-empty?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . if (EAX != 0) break
+    3d/compare-EAX-and  0/imm32
+    0f 85/jump-if-not-equal  $convert-data:break/disp32
+$convert-data:check-for-comment:
+    # if (slice-starts-with?(word-slice, "#"))
+    # . start/EDX = word-slice->start
+    8b/copy                         0/mod/indirect  1/rm32/ECX    .           .             .           2/r32/EDX   .               .                 # copy *ECX to EDX
+    # . c/EAX = *start
+    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
+    8a/copy-byte                    0/mod/indirect  2/rm32/EDX    .           .             .           0/r32/AL    .               .                 # copy byte at *EDX to AL
+    # . if (EAX != '#') goto next check
+    3d/compare-EAX-and  0x23/imm32/hash
+    75/jump-if-not-equal  $convert-data:check-for-label/disp8
+$convert-data:comment:
+    # write-slice-buffered(out, word-slice)
+    # . . push args
+    51/push-ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write-slice-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # return
+    0f 85/jump-if-not-equal  $convert-data:end/disp32
+$convert-data:check-for-label:
+    # if (slice-ends-with?(word-slice, ":"))
+    # . end/EDX = word-slice->end
+    8b/copy                         1/mod/*+disp8   1/rm32/ECX    .           .             .           2/r32/EDX   4/disp8         .                 # copy *(ECX+4) to EDX
+    # . c/EAX = *(end-1)
+    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
+    8a/copy-byte                    1/mod/*+disp8   2/rm32/EDX    .           .             .           0/r32/AL    -1/disp8        .                 # copy byte at *ECX to AL
+    # . if (EAX != ':') goto next check
+    3d/compare-EAX-and  0x3a/imm32/colon
+    75/jump-if-not-equal  $convert-data:check-for-imm32/disp8
+$convert-data:label:
+    # write-stream-data(out, line)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write-stream-data/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # return
+    75/jump-if-not-equal  $convert-data:end/disp8
+$convert-data:check-for-imm32:
+    # if (has-metadata?(word-slice, "imm32"))
+    # . EAX = has-metadata?(ECX, "imm32")
+    # . . push args
+    68/push  "imm32"/imm32
+    51/push-ECX
+    # . . call
+    e8/call  has-metadata?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX == 0) process as a single byte
+    3d/compare-EAX-and  0/imm32
+    74/jump-if-equal  $convert-data:single-byte/disp8
+$convert-data:imm32:
+    # emit(out, word-slice, 4)
+    # . . push args
+    68/push  4/imm32
+    51/push-ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  emit/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    e9/jump  $convert-data:loop/disp32
+$convert-data:single-byte:
+    # emit(out, word-slice, 1)
+    # . . push args
+    68/push  1/imm32
+    51/push-ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  emit/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    e9/jump  $convert-data:loop/disp32
+$convert-data:break:
+    # write-buffered(out, "\n")
+    # . . push args
+    68/push  "\n"/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+$convert-data:end:
+    # . reclaim locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . restore registers
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-data-passes-comments-through:
+    # if a line starts with '#', pass it along unchanged
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "# abcd")
+    # . . push args
+    68/push  "# abcd"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-data(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-data/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check that the line just passed through
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-stream-equal(_test-output-stream, "# abcd", msg)
+    # . . push args
+    68/push  "F - test-convert-data-passes-comments-through"/imm32
+    68/push  "# abcd"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-data-passes-labels-through:
+    # if the first word ends with ':', pass along the entire line unchanged
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "ab: # cd")
+    # . . push args
+    68/push  "ab: # cd"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-data(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-data/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check that the line just passed through
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . check-stream-equal(_test-output-stream, "ab: # cd", msg)
+    # . . push args
+    68/push  "F - test-convert-data-passes-labels-through"/imm32
+    68/push  "ab: # cd"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-data-passes-names-through:
+    # If a word is a valid name, just emit it unchanged.
+    # Later phases will deal with it.
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "abcd/imm32")
+    # . . push args
+    68/push  "abcd/imm32"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-data(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-data/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check that the line just passed through
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . check-stream-equal(_test-output-stream, "abcd/imm32 \n", msg)
+    # . . push args
+    68/push  "F - test-convert-data-passes-names-through"/imm32
+    68/push  "abcd/imm32 \n"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-data-handles-imm32:
+    # If a word has the /imm32 metadata, emit it in 4 bytes.
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "30/imm32")
+    # . . push args
+    68/push  "30/imm32"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-data(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-data/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check that 4 bytes were written
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . check-stream-equal(_test-output-stream, "30 00 00 00 \n", msg)
+    # . . push args
+    68/push  "F - test-convert-data-handles-imm32"/imm32
+    68/push  "30 00 00 00 \n"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-data-handles-single-byte:
+    # Any metadata but /imm32 will emit a single byte.
+    # Data segments can't have /disp32, and SubX doesn't support 16-bit operands.
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "30/imm16")
+    # . . push args
+    68/push  "30/imm16"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-data(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-data/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check that a single byte was written (imm16 is not a valid operand type)
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . check-stream-equal(_test-output-stream, "30 \n", msg)
+    # . . push args
+    68/push  "F - test-convert-data-handles-single-byte"/imm32
+    68/push  "30 \n"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-data-multiple-bytes:
+    # Multiple single-byte words in input stream get processed one by one.
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "1 2")
+    # . . push args
+    68/push  "1 2"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-data(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-data/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check output
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . check-stream-equal(_test-output-stream, "01 02 \n", msg)
+    # . . push args
+    68/push  "F - test-convert-data-multiple-bytes"/imm32
+    68/push  "01 02 \n"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-data-byte-then-name:
+    # Single-byte word followed by valid name get processed one by one.
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "30 abcd/o")
+    # . . push args
+    68/push  "30 abcd/o"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-data(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-data/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check output
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . check-stream-equal(_test-output-stream, "30 abcd/o \n", msg)
+    # . . push args
+    68/push  "F - test-convert-data-byte-then-name"/imm32
+    68/push  "30 abcd/o \n"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-data-multiple-words:
+    # Multiple words in input stream get processed one by one.
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "30 abcd/o 42e1/imm32")
+    # . . push args
+    68/push  "30 abcd/o 42e1/imm32"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-data(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-data/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check output
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-stream-equal(_test-output-stream, "30 abcd/o 42 e1 00 00 \n", msg)
+    # . . push args
+    68/push  "F - test-convert-data-multiple-words"/imm32
+    68/push  "30 abcd/o e1 42 00 00 \n"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-data-trailing-comment:
+    # Trailing comments in data segment get appropriately ignored.
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "30/imm32 # comment")
+    # . . push args
+    68/push  "30/imm32 # comment"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-data(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-data/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check output
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-stream-equal(_test-output-stream, "30 00 00 00 # comment", msg)
+    # . . push args
+    68/push  "F - test-convert-data-trailing-comment"/imm32
+    68/push  "30 00 00 00 # comment"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+# pack an instruction, following the C++ version
+#
+# zero error handling at the moment (continuing to rely on the C++ version for that):
+#   missing fields are always 0-filled
+#   bytes never mentioned are silently dropped; if you don't provide /mod, /rm32 or /r32 you don't get a 0 ModR/M byte. You get *no* ModR/M byte.
+#   may pick up any of duplicate operands in an instruction
+#   silently drop extraneous operands
+#   unceremoniously abort on non-numeric operands except disp or imm
+#   opcodes must be lowercase and zero padded
+#   opcodes with misleading operand metadata may get duplicated as operands as well. don't rely on this.
+convert-instruction:  # line : (address stream byte), out : (address buffered-file) -> <void>
+    # pseudocode:
+    #   # some early exits
+    #   var word-slice = next-word(line)
+    #   if slice-empty?(word-slice)
+    #     write-stream-data(out, line)
+    #     return
+    #   if slice-starts-with?(word-slice, "#")
+    #     write-stream-data(out, line)
+    #     return
+    #   if slice-ends-with?(word-slice, ":")
+    #     write-stream-data(out, line)
+    #     return
+    #   # really convert
+    #   emit-opcodes(line, out)
+    #   emit-modrm(line, out)
+    #   emit-sib(line, out)
+    #   emit-disp(line, out)
+    #   emit-imm(line, out)
+    #   emit-line-in-comment(line, out)
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+    51/push-ECX
+    52/push-EDX
+    # var word-slice/ECX = {0, 0}
+    68/push  0/imm32/end
+    68/push  0/imm32/start
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # next-word(line, word-slice)
+    # . . push args
+    51/push-ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  next-word/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+$convert-instruction:check0:
+    # if (slice-empty?(word-slice)) break
+    # . EAX = slice-empty?(word-slice)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  slice-empty?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . if (EAX != 0) pass through
+    3d/compare-EAX-and  0/imm32
+    75/jump-if-not-equal  $convert-instruction:pass-through/disp8
+$convert-instruction:check1:
+    # if (slice-starts-with?(word-slice, "#")) write-stream-data(out, line)
+    # . start/EDX = word-slice->start
+    8b/copy                         0/mod/indirect  1/rm32/ECX    .           .             .           2/r32/EDX   .               .                 # copy *ECX to EDX
+    # . c/EAX = *start
+    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
+    8a/copy-byte                    0/mod/indirect  2/rm32/EDX    .           .             .           0/r32/AL    .               .                 # copy byte at *EDX to AL
+    # . if (EAX == '#') pass through
+    3d/compare-EAX-and  0x23/imm32/hash
+    74/jump-if-equal  $convert-instruction:pass-through/disp8
+$convert-instruction:check2:
+    # if (slice-ends-with?(word-slice, ":")) write-stream-data(out, line)
+    # . end/EDX = word-slice->end
+    8b/copy                         1/mod/*+disp8   1/rm32/ECX    .           .             .           2/r32/EDX   4/disp8         .                 # copy *(ECX+4) to EDX
+    # . c/EAX = *(end-1)
+    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
+    8a/copy-byte                    1/mod/*+disp8   2/rm32/EDX    .           .             .           0/r32/AL    -1/disp8        .                 # copy byte at *ECX to AL
+    # . if (EAX == ':') pass through
+    3d/compare-EAX-and  0x3a/imm32/colon
+    75/jump-if-not-equal  $convert-instruction:really-convert/disp8
+$convert-instruction:pass-through:
+    # write-stream-data(out, line)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write-stream-data/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # return
+    eb/jump  $convert-instruction:end/disp8
+$convert-instruction:really-convert:
+    # emit-opcodes(line, out)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  emit-opcodes/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # emit-modrm(line, out)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  emit-modrm/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # emit-sib(line, out)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  emit-sib/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # emit-disp(line, out)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  emit-disp/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # emit-imm(line, out)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  emit-imm/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # emit-line-in-comment(line, out)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  emit-line-in-comment/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+$convert-instruction:end:
+    # . restore locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . restore registers
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+emit-opcodes:  # line : (address stream byte), out : (address buffered-file) -> <void>
+    # opcodes occupy 1-3 bytes:
+    #   xx
+    #   0f xx
+    #   f2 xx
+    #   f3 xx
+    #   f2 0f xx
+    #   f3 0f xx
+    #
+    # pseudocode:
+    #   rewind-stream(line)
+    #
+    #   var op1 = next-word(line)
+    #   if (slice-empty?(op1) || slice-starts-with?(op1, "#")) return
+    #   op1 = next-token-from-slice(op1->start, op1->end, "/")
+    #   write-slice-buffered(out, op1)
+    #   if !slice-equal?(op1, "0f") && !slice-equal?(op1, "f2") && !slice-equal?(op1, "f3")
+    #     return
+    #
+    #   var op2 = next-word(line)
+    #   if (slice-empty?(op2) || slice-starts-with?(op2, "#")) return
+    #   op2 = next-token-from-slice(op2->start, op2->end, "/")
+    #   write-slice-buffered(out, op2)
+    #   if slice-equal?(op1, "0f")
+    #     return
+    #   if !slice-equal?(op2, "0f")
+    #     return
+    #
+    #   var op3 = next-word(line)
+    #   if (slice-empty?(op3) || slice-starts-with?(op3, "#")) return
+    #   op3 = next-token-from-slice(op3->start, op3->end, "/")
+    #   write-slice-buffered(out, op3)
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+    51/push-ECX
+    52/push-EDX
+    53/push-EBX
+    # var op1/ECX = {0, 0}
+    68/push  0/imm32/end
+    68/push  0/imm32/start
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # var op2/EDX = {0, 0}
+    68/push  0/imm32/end
+    68/push  0/imm32/start
+    89/copy                         3/mod/direct    2/rm32/EDX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EDX
+    # rewind-stream(line)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  rewind-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+$emit-opcodes:op1:
+    # next-word(line, op1)
+    # . . push args
+    51/push-ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  next-word/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # if (slice-empty?(op1)) return
+    # . EAX = slice-empty?(op1)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  slice-empty?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . if (EAX != 0) return
+    3d/compare-EAX-and  0/imm32
+    0f 85/jump-if-not-equal  $emit-opcodes:end/disp32
+    # if (slice-starts-with?(op1, "#")) return
+    # . start/EBX = op1->start
+    8b/copy                         0/mod/indirect  1/rm32/ECX    .           .             .           3/r32/EBX   .               .                 # copy *ECX to EBX
+    # . c/EAX = *start
+    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
+    8a/copy-byte                    0/mod/indirect  3/rm32/EBX    .           .             .           0/r32/AL    .               .                 # copy byte at *EBX to AL
+    # . if (EAX == '#') return
+    3d/compare-EAX-and  0x23/imm32/hash
+    0f 84/jump-if-equal  $emit-opcodes:end/disp32
+    # op1 = next-token-from-slice(op1->start, op1->end, '/')
+    # . . push args
+    51/push-ECX
+    68/push  0x2f/imm32/slash
+    ff          6/subop/push        1/mod/*+disp8   1/rm32/ECX    .           .             .           .           4/disp8         .                 # push *(ECX+4)
+    ff          6/subop/push        0/mod/indirect  1/rm32/ECX    .           .             .           .           .               .                 # push *ECX
+    # . . call
+    e8/call  next-token-from-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
+    # write-slice-buffered(out, op1)
+    # . . push args
+    51/push-ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write-slice-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # write-buffered(out, " ")
+    # . . push args
+    68/push  " "/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # if (slice-equal?(op1, "0f")) goto op2
+    # . EAX = slice-equal?(op1, "0f")
+    # . . push args
+    68/push  "0f"/imm32
+    51/push-ECX
+    # . . call
+    e8/call  slice-equal?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX != 0) goto op2
+    3d/compare-EAX-and  0/imm32
+    75/jump-if-not-equal  $emit-opcodes:op2/disp8
+    # if (slice-equal?(op1, "f2")) goto op2
+    # . EAX = slice-equal?(op1, "f2")
+    # . . push args
+    68/push  "f2"/imm32
+    51/push-ECX
+    # . . call
+    e8/call  slice-equal?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX != 0) goto op2
+    3d/compare-EAX-and  0/imm32
+    75/jump-if-not-equal  $emit-opcodes:op2/disp8
+    # if (slice-equal?(op1, "f3")) goto op2
+    # . EAX = slice-equal?(op1, "f3")
+    # . . push args
+    68/push  "f3"/imm32
+    51/push-ECX
+    # . . call
+    e8/call  slice-equal?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX != 0) goto op2
+    3d/compare-EAX-and  0/imm32
+    75/jump-if-not-equal  $emit-opcodes:op2/disp8
+    # otherwise return
+    e9/jump  $emit-opcodes:end/disp32
+$emit-opcodes:op2:
+    # next-word(line, op2)
+    # . . push args
+    52/push-EDX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  next-word/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # if (slice-empty?(op2)) return
+    # . EAX = slice-empty?(op2)
+    # . . push args
+    52/push-EDX
+    # . . call
+    e8/call  slice-empty?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . if (EAX != 0) return
+    3d/compare-EAX-and  0/imm32
+    0f 85/jump-if-not-equal  $emit-opcodes:end/disp32
+    # if (slice-starts-with?(op2, "#")) return
+    # . start/EBX = op2->start
+    8b/copy                         0/mod/indirect  2/rm32/EDX    .           .             .           3/r32/EBX   .               .                 # copy *EDX to EBX
+    # . c/EAX = *start
+    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
+    8a/copy-byte                    0/mod/indirect  3/rm32/EBX    .           .             .           0/r32/AL    .               .                 # copy byte at *EBX to AL
+    # . if (EAX == '#') return
+    3d/compare-EAX-and  0x23/imm32/hash
+    0f 84/jump-if-equal  $emit-opcodes:end/disp32
+    # op2 = next-token-from-slice(op2->start, op2->end, '/')
+    # . . push args
+    52/push-EDX
+    68/push  0x2f/imm32/slash
+    ff          6/subop/push        1/mod/*+disp8   2/rm32/EDX    .           .             .           .           4/disp8         .                 # push *(EDX+4)
+    ff          6/subop/push        0/mod/indirect  2/rm32/EDX    .           .             .           .           .               .                 # push *EDX
+    # . . call
+    e8/call  next-token-from-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
+    # write-slice-buffered(out, op2)
+    # . . push args
+    52/push-EDX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write-slice-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # write-buffered(out, " ")
+    # . . push args
+    68/push  " "/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # if (slice-equal?(op1, "0f")) return
+    # . EAX = slice-equal?(op1, "0f")
+    # . . push args
+    68/push  "0f"/imm32
+    51/push-ECX
+    # . . call
+    e8/call  slice-equal?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX != 0) return
+    3d/compare-EAX-and  0/imm32
+    0f 85/jump-if-not-equal  $emit-opcodes:end/disp32
+    # if (!slice-equal?(op2, "0f")) return
+    # . EAX = slice-equal?(op2, "0f")
+    # . . push args
+    68/push  "0f"/imm32
+    52/push-EDX
+    # . . call
+    e8/call  slice-equal?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX == 0) return
+    3d/compare-EAX-and  0/imm32
+    0f 84/jump-if-equal  $emit-opcodes:end/disp32
+$emit-opcodes:op3:
+    # next-word(line, op3)  # reuse op2/EDX
+    # . . push args
+    52/push-EDX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  next-word/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # if (slice-empty?(op3)) return
+    # . EAX = slice-empty?(op3)
+    # . . push args
+    52/push-EDX
+    # . . call
+    e8/call  slice-empty?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . if (EAX != 0) return
+    3d/compare-EAX-and  0/imm32
+    0f 85/jump-if-not-equal  $emit-opcodes:end/disp32
+    # if (slice-starts-with?(op3, "#")) return
+    # . start/EBX = op2->start
+    8b/copy                         0/mod/indirect  2/rm32/EDX    .           .             .           3/r32/EBX   .               .                 # copy *EDX to EBX
+    # . c/EAX = *start
+    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
+    8a/copy-byte                    0/mod/indirect  3/rm32/EBX    .           .             .           0/r32/AL    .               .                 # copy byte at *EBX to AL
+    # . if (EAX == '#') return
+    3d/compare-EAX-and  0x23/imm32/hash
+    0f 84/jump-if-equal  $emit-opcodes:end/disp32
+    # op3 = next-token-from-slice(op3->start, op3->end, '/')
+    # . . push args
+    52/push-EDX
+    68/push  0x2f/imm32/slash
+    ff          6/subop/push        1/mod/*+disp8   2/rm32/EDX    .           .             .           .           4/disp8         .                 # push *(EDX+4)
+    ff          6/subop/push        0/mod/indirect  2/rm32/EDX    .           .             .           .           .               .                 # push *EDX
+    # . . call
+    e8/call  next-token-from-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
+    # write-slice-buffered(out, op3)
+    # . . push args
+    52/push-EDX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write-slice-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # write-buffered(out, " ")
+    # . . push args
+    68/push  " "/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+$emit-opcodes:end:
+    # . restore locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
+    # . restore registers
+    5b/pop-to-EBX
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+emit-modrm:  # line : (address stream byte), out : (address buffered-file) -> <void>
+    # pseudocode:
+    #   rewind-stream(line)
+    #   var has-modrm? = false, mod = 0, rm32 = 0, r32 = 0
+    #   var word-slice = {0, 0}
+    #   while true
+    #     word-slice = next-word(line)
+    #     if (slice-empty?(word-slice)) break
+    #     if (slice-starts-with?(word-slice, "#")) break
+    #     if (has-metadata?(word-slice, "mod"))
+    #       mod = parse-hex-int(next-token-from-slice(word-slice, "/"))
+    #       has-modrm? = true
+    #     else if (has-metadata?(word-slice, "rm32"))
+    #       rm32 = parse-hex-int(next-token-from-slice(word-slice, "/"))
+    #       has-modrm? = true
+    #     else if (has-metadata?(word-slice, "r32") or has-metadata?(word-slice, "subop"))
+    #       r32 = parse-hex-int(next-token-from-slice(word-slice, "/"))
+    #       has-modrm? = true
+    #   if has-modrm?
+    #     var modrm = mod & 0b11
+    #     modrm <<= 3
+    #     modrm |= r32 & 0b111
+    #     modrm <<= 3
+    #     modrm |= rm32 & 0b111
+    #     emit-hex(out, modrm, 1)
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+    51/push-ECX
+    52/push-EDX
+    53/push-EBX
+    56/push-ESI
+    57/push-EDI
+    # var word-slice/ECX = {0, 0}
+    68/push  0/imm32/end
+    68/push  0/imm32/start
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # var has-modrm?/EDX = false
+    31/xor                          3/mod/direct    2/rm32/EDX    .           .             .           2/r32/EDX   .               .                 # clear EDX
+    # var mod/EBX = 0
+    31/xor                          3/mod/direct    3/rm32/EBX    .           .             .           3/r32/EBX   .               .                 # clear EBX
+    # var rm32/ESI = 0
+    31/xor                          3/mod/direct    6/rm32/ESI    .           .             .           6/r32/ESI   .               .                 # clear ESI
+    # var r32/EDI = 0
+    31/xor                          3/mod/direct    7/rm32/EDI    .           .             .           7/r32/EDI   .               .                 # clear EDI
+    # rewind-stream(line)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  rewind-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump line {{{
+#?     # . write(2/stderr, "LL: ")
+#?     # . . push args
+#?     68/push  "LL: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, line)
+#?     # . . push args
+#?     ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . rewind-stream(line)
+#?     # . . push args
+#?     ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+#?     # . . call
+#?     e8/call  rewind-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # }}}
+$emit-modrm:loop:
+    # next-word(line, word-slice)
+    # . . push args
+    51/push-ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  next-word/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # dump word-slice {{{
+#?     # . write(2/stderr, "AA: ")
+#?     # . . push args
+#?     68/push  "AA: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . clear-stream(Stderr+4)
+#?     # . . push args
+#?     b8/copy-to-EAX  Stderr/imm32
+#?     05/add-to-EAX  4/imm32
+#?     50/push-EAX
+#?     # . . call
+#?     e8/call  clear-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . write-slice-buffered(Stderr, word-slice)
+#?     # . . push args
+#?     51/push-ECX
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  write-slice-buffered/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . flush(Stderr)
+#?     # . . push args
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  flush/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+$emit-modrm:check0:
+    # if (slice-empty?(word-slice)) break
+    # . EAX = slice-empty?(word-slice)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  slice-empty?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . if (EAX != 0) pass through
+    3d/compare-EAX-and  0/imm32
+    0f 85/jump-if-not-equal  $emit-modrm:break/disp32
+$emit-modrm:check1:
+    # if (slice-starts-with?(word-slice, "#")) break
+    # . spill EDX
+    52/push-EDX
+    # . start/EDX = word-slice->start
+    8b/copy                         0/mod/indirect  1/rm32/ECX    .           .             .           2/r32/EDX   .               .                 # copy *ECX to EDX
+    # . c/EAX = *start
+    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
+    8a/copy-byte                    0/mod/indirect  2/rm32/EDX    .           .             .           0/r32/AL    .               .                 # copy byte at *EDX to AL
+    # . restore EDX
+    5a/pop-to-EDX
+    # . if (EAX == '#') pass through
+    3d/compare-EAX-and  0x23/imm32/hash
+    0f 84/jump-if-equal  $emit-modrm:break/disp32
+$emit-modrm:check-for-mod:
+    # if (has-metadata?(word-slice, "mod"))
+    # . EAX = has-metadata?(ECX, "mod")
+    # . . push args
+    68/push  "mod"/imm32
+    51/push-ECX
+    # . . call
+    e8/call  has-metadata?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX == 0) goto next check
+    3d/compare-EAX-and  0/imm32
+    74/jump-if-equal  $emit-modrm:check-for-rm32/disp8
+$emit-modrm:mod:
+    # mod = parse-hex-int(next-token-from-slice(word-slice->start, word-slice->end, '/'))
+    # . EAX = parse-datum-of-word(word-slice)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  parse-datum-of-word/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . mod = EAX
+    89/copy                         3/mod/direct    3/rm32/EBX    .           .             .           0/r32/EAX   .               .                 # copy EAX to EBX
+    # has-modrm? = true
+    ba/copy-to-EDX  1/imm32/true
+    # continue
+    e9/jump  $emit-modrm:loop/disp32
+$emit-modrm:check-for-rm32:
+    # if (has-metadata?(word-slice, "rm32"))
+    # . EAX = has-metadata?(ECX, "rm32")
+    # . . push args
+    68/push  "rm32"/imm32
+    51/push-ECX
+    # . . call
+    e8/call  has-metadata?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX == 0) goto next check
+    3d/compare-EAX-and  0/imm32
+    74/jump-if-equal  $emit-modrm:check-for-r32/disp8
+$emit-modrm:rm32:
+    # rm32 = parse-hex-int(next-token-from-slice(word-slice->start, word-slice->end, '/'))
+    # . EAX = parse-datum-of-word(word-slice)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  parse-datum-of-word/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . rm32 = EAX
+    89/copy                         3/mod/direct    6/rm32/ESI    .           .             .           0/r32/EAX   .               .                 # copy EAX to ESI
+    # has-modrm? = true
+    ba/copy-to-EDX  1/imm32/true
+    # continue
+    e9/jump  $emit-modrm:loop/disp32
+$emit-modrm:check-for-r32:
+    # if (has-metadata?(word-slice, "r32"))
+    # . EAX = has-metadata?(ECX, "r32")
+    # . . push args
+    68/push  "r32"/imm32
+    51/push-ECX
+    # . . call
+    e8/call  has-metadata?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX == 0) goto next check
+    3d/compare-EAX-and  0/imm32
+    74/jump-if-equal  $emit-modrm:check-for-subop/disp8
+$emit-modrm:r32:
+    # r32 = parse-hex-int(next-token-from-slice(word-slice->start, word-slice->end, '/'))
+    # . EAX = parse-datum-of-word(word-slice)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  parse-datum-of-word/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . r32 = EAX
+    89/copy                         3/mod/direct    7/rm32/EDI    .           .             .           0/r32/EAX   .               .                 # copy EAX to EDI
+    # has-modrm? = true
+    ba/copy-to-EDX  1/imm32/true
+    # continue
+    e9/jump  $emit-modrm:loop/disp32
+$emit-modrm:check-for-subop:
+    # if (has-metadata?(word-slice, "subop"))
+    # . EAX = has-metadata?(ECX, "subop")
+    # . . push args
+    68/push  "subop"/imm32
+    51/push-ECX
+    # . . call
+    e8/call  has-metadata?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX == 0) loop
+    3d/compare-EAX-and  0/imm32
+    0f 84/jump-if-equal  $emit-modrm:loop/disp32
+$emit-modrm:subop:
+    # r32 = parse-hex-int(next-token-from-slice(word-slice->start, word-slice->end, '/'))
+    # . EAX = parse-datum-of-word(word-slice)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  parse-datum-of-word/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . r32 = EAX
+    89/copy                         3/mod/direct    7/rm32/EDI    .           .             .           0/r32/EAX   .               .                 # copy EAX to EDI
+    # has-modrm? = true
+    ba/copy-to-EDX  1/imm32/true
+    # continue
+    e9/jump  $emit-modrm:loop/disp32
+$emit-modrm:break:
+    # if (!has-modrm?) return
+    81          7/subop/compare     3/mod/direct    2/rm32/EDX    .           .             .           .           .               0/imm32           # compare EDX
+    74/jump-if-equal  $emit-modrm:end/disp8
+$emit-modrm:calculate:
+    # modrm/EBX = mod & 0b11
+    81          4/subop/and         3/mod/direct    3/rm32/EBX    .           .             .           .           .               3/imm32/0b11      # bitwise and of EBX
+    # modrm <<= 3
+    c1/shift    4/subop/left        3/mod/direct    3/rm32/EBX    .           .             .           .           .               3/imm8            # shift EBX left by 3 bits
+    # modrm |= r32 & 0b111
+    81          4/subop/and         3/mod/direct    7/rm32/EDI    .           .             .           .           .               7/imm32/0b111     # bitwise and of EDI
+    09/or                           3/mod/direct    3/rm32/EBX    .           .             .           7/r32/EDI   .               .                 # EBX = bitwise OR with EDI
+    # modrm <<= 3
+    c1/shift    4/subop/left        3/mod/direct    3/rm32/EBX    .           .             .           .           .               3/imm8            # shift EBX left by 3 bits
+    # modrm |= rm32 & 0b111
+    81          4/subop/and         3/mod/direct    6/rm32/ESI    .           .             .           .           .               7/imm32/0b111     # bitwise and of ESI
+    09/or                           3/mod/direct    3/rm32/EBX    .           .             .           6/r32/ESI   .               .                 # EBX = bitwise OR with ESI
+$emit-modrm:emit:
+    # emit-hex(out, modrm, 1)
+    # . . push args
+    68/push  1/imm32
+    53/push-EBX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  emit-hex/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$emit-modrm:end:
+    # . restore locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . restore registers
+    5f/pop-to-EDI
+    5e/pop-to-ESI
+    5b/pop-to-EBX
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+emit-sib:  # line : (address stream byte), out : (address buffered-file) -> <void>
+    # pseudocode:
+    #   var has-sib? = false, base = 0, index = 0, scale = 0
+    #   var word-slice = {0, 0}
+    #   while true
+    #     word-slice = next-word(line)
+    #     if (slice-empty?(word-slice)) break
+    #     if (slice-starts-with?(word-slice, "#")) break
+    #     if (has-metadata?(word-slice, "base")
+    #       base = parse-hex-int(next-token-from-slice(word-slice, "/"))
+    #       has-sib? = true
+    #     else if (has-metadata?(word-slice, "index")
+    #       index = parse-hex-int(next-token-from-slice(word-slice, "/"))
+    #       has-sib? = true
+    #     else if (has-metadata?(word-slice, "scale")
+    #       scale = parse-hex-int(next-token-from-slice(word-slice, "/"))
+    #       has-sib? = true
+    #   if has-sib?
+    #     var sib = scale & 0b11
+    #     sib <<= 2
+    #     sib |= index & 0b111
+    #     sib <<= 3
+    #     sib |= base & 0b111
+    #     emit-hex(out, sib, 1)
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+    51/push-ECX
+    52/push-EDX
+    53/push-EBX
+    56/push-ESI
+    57/push-EDI
+    # var word-slice/ECX = {0, 0}
+    68/push  0/imm32/end
+    68/push  0/imm32/start
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # var has-sib?/EDX = false
+    31/xor                          3/mod/direct    2/rm32/EDX    .           .             .           2/r32/EDX   .               .                 # clear EDX
+    # var scale/EBX = 0
+    31/xor                          3/mod/direct    3/rm32/EBX    .           .             .           3/r32/EBX   .               .                 # clear EBX
+    # var base/ESI = 0
+    31/xor                          3/mod/direct    6/rm32/ESI    .           .             .           6/r32/ESI   .               .                 # clear ESI
+    # var index/EDI = 0
+    31/xor                          3/mod/direct    7/rm32/EDI    .           .             .           7/r32/EDI   .               .                 # clear EDI
+    # rewind-stream(line)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  rewind-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+$emit-sib:loop:
+#?     # dump line {{{
+#?     # . write(2/stderr, "LL: ")
+#?     # . . push args
+#?     68/push  "LL: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, line)
+#?     # . . push args
+#?     ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # next-word(line, word-slice)
+    # . . push args
+    51/push-ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  next-word/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # dump word-slice {{{
+#?     # . write(2/stderr, "AA: ")
+#?     # . . push args
+#?     68/push  "AA: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . clear-stream(Stderr+4)
+#?     # . . push args
+#?     b8/copy-to-EAX  Stderr/imm32
+#?     05/add-to-EAX  4/imm32
+#?     50/push-EAX
+#?     # . . call
+#?     e8/call  clear-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . write-slice-buffered(Stderr, word-slice)
+#?     # . . push args
+#?     51/push-ECX
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  write-slice-buffered/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . flush(Stderr)
+#?     # . . push args
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  flush/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+$emit-sib:check0:
+    # if (slice-empty?(word-slice)) break
+    # . EAX = slice-empty?(word-slice)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  slice-empty?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . if (EAX != 0) pass through
+    3d/compare-EAX-and  0/imm32
+    0f 85/jump-if-not-equal  $emit-sib:break/disp32
+$emit-sib:check1:
+    # if (slice-starts-with?(word-slice, "#")) break
+    # . spill EDX
+    52/push-EDX
+    # . start/EDX = word-slice->start
+    8b/copy                         0/mod/indirect  1/rm32/ECX    .           .             .           2/r32/EDX   .               .                 # copy *ECX to EDX
+    # . c/EAX = *start
+    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
+    8a/copy-byte                    0/mod/indirect  2/rm32/EDX    .           .             .           0/r32/AL    .               .                 # copy byte at *EDX to AL
+    # . restore EDX
+    5a/pop-to-EDX
+    # . if (EAX == '#') pass through
+    3d/compare-EAX-and  0x23/imm32/hash
+    0f 84/jump-if-equal  $emit-sib:break/disp32
+$emit-sib:check-for-scale:
+    # if (has-metadata?(word-slice, "scale"))
+    # . EAX = has-metadata?(ECX, "scale")
+    # . . push args
+    68/push  "scale"/imm32
+    51/push-ECX
+    # . . call
+    e8/call  has-metadata?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX == 0) goto next check
+    3d/compare-EAX-and  0/imm32
+    74/jump-if-equal  $emit-sib:check-for-base/disp8
+$emit-sib:scale:
+    # scale = parse-hex-int(next-token-from-slice(word-slice->start, word-slice->end, '/'))
+    # . EAX = parse-datum-of-word(word-slice)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  parse-datum-of-word/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . scale = EAX
+    89/copy                         3/mod/direct    3/rm32/EBX    .           .             .           0/r32/EAX   .               .                 # copy EAX to EBX
+    # has-sib? = true
+    ba/copy-to-EDX  1/imm32/true
+    # continue
+    e9/jump  $emit-sib:loop/disp32
+$emit-sib:check-for-base:
+    # if (has-metadata?(word-slice, "base"))
+    # . EAX = has-metadata?(ECX, "base")
+    # . . push args
+    68/push  "base"/imm32
+    51/push-ECX
+    # . . call
+    e8/call  has-metadata?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX == 0) goto next check
+    3d/compare-EAX-and  0/imm32
+    74/jump-if-equal  $emit-sib:check-for-index/disp8
+$emit-sib:base:
+    # base = parse-hex-int(next-token-from-slice(word-slice->start, word-slice->end, '/'))
+    # . EAX = parse-datum-of-word(word-slice)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  parse-datum-of-word/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . base = EAX
+    89/copy                         3/mod/direct    6/rm32/ESI    .           .             .           0/r32/EAX   .               .                 # copy EAX to ESI
+    # has-sib? = true
+    ba/copy-to-EDX  1/imm32/true
+    # continue
+    e9/jump  $emit-sib:loop/disp32
+$emit-sib:check-for-index:
+    # if (has-metadata?(word-slice, "index"))
+    # . EAX = has-metadata?(ECX, "index")
+    # . . push args
+    68/push  "index"/imm32
+    51/push-ECX
+    # . . call
+    e8/call  has-metadata?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX == 0) loop
+    3d/compare-EAX-and  0/imm32
+    0f 84/jump-if-equal  $emit-sib:loop/disp32
+$emit-sib:index:
+    # index = parse-hex-int(next-token-from-slice(word-slice->start, word-slice->end, '/'))
+    # . EAX = parse-datum-of-word(word-slice)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  parse-datum-of-word/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . index = EAX
+    89/copy                         3/mod/direct    7/rm32/EDI    .           .             .           0/r32/EAX   .               .                 # copy EAX to EDI
+    # has-sib? = true
+    ba/copy-to-EDX  1/imm32/true
+    # continue
+    e9/jump  $emit-sib:loop/disp32
+$emit-sib:break:
+    # if (!has-sib?) return
+    81          7/subop/compare     3/mod/direct    2/rm32/EDX    .           .             .           .           .               0/imm32           # compare EDX
+    74/jump-if-equal  $emit-sib:end/disp8
+$emit-sib:calculate:
+    # sib/EBX = scale & 0b11
+    81          4/subop/and         3/mod/direct    3/rm32/EBX    .           .             .           .           .               3/imm32/0b11      # bitwise and of EBX
+    # sib <<= 2
+    c1/shift    4/subop/left        3/mod/direct    3/rm32/EBX    .           .             .           .           .               2/imm8            # shift EBX left by 2 bits
+    # sib |= index & 0b111
+    81          4/subop/and         3/mod/direct    7/rm32/EDI    .           .             .           .           .               7/imm32/0b111     # bitwise and of EDI
+    09/or                           3/mod/direct    3/rm32/EBX    .           .             .           7/r32/EDI   .               .                 # EBX = bitwise OR with EDI
+    # sib <<= 3
+    c1/shift    4/subop/left        3/mod/direct    3/rm32/EBX    .           .             .           .           .               3/imm8            # shift EBX left by 3 bits
+    # sib |= base & 0b111
+    81          4/subop/and         3/mod/direct    6/rm32/ESI    .           .             .           .           .               7/imm32/0b111     # bitwise and of ESI
+    09/or                           3/mod/direct    3/rm32/EBX    .           .             .           6/r32/ESI   .               .                 # EBX = bitwise OR with ESI
+$emit-sib:emit:
+    # emit-hex(out, sib, 1)
+    # . . push args
+    68/push  1/imm32
+    53/push-EBX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  emit-hex/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$emit-sib:end:
+    # . restore locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . restore registers
+    5f/pop-to-EDI
+    5e/pop-to-ESI
+    5b/pop-to-EBX
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+emit-disp:  # line : (address stream byte), out : (address buffered-file) -> <void>
+    # pseudocode:
+    #   rewind-stream(line)
+    #   var word-slice = {0, 0}
+    #   while true
+    #     word-slice = next-word(line)
+    #     if (slice-empty?(word-slice)) break
+    #     if (slice-starts-with?(word-slice, "#")) break
+    #     if has-metadata?(word-slice, "disp32")
+    #       emit(out, word-slice, 4)
+    #       break
+    #     if has-metadata?(word-slice, "disp16")
+    #       emit(out, word-slice, 2)
+    #       break
+    #     if has-metadata?(word-slice, "disp8")
+    #       emit(out, word-slice, 1)
+    #       break
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+    51/push-ECX
+    52/push-EDX
+    # var word-slice/ECX = {0, 0}
+    68/push  0/imm32/end
+    68/push  0/imm32/start
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # rewind-stream(line)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  rewind-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump line {{{
+#?     # . write(2/stderr, "LL: ")
+#?     # . . push args
+#?     68/push  "LL: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, line)
+#?     # . . push args
+#?     ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+$emit-disp:loop:
+    # next-word(line, word-slice)
+    # . . push args
+    51/push-ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  next-word/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # dump word-slice {{{
+#?     # . write(2/stderr, "AA: ")
+#?     # . . push args
+#?     68/push  "AA: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . clear-stream(Stderr+4)
+#?     # . . push args
+#?     b8/copy-to-EAX  Stderr/imm32
+#?     05/add-to-EAX  4/imm32
+#?     50/push-EAX
+#?     # . . call
+#?     e8/call  clear-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . write-slice-buffered(Stderr, word-slice)
+#?     # . . push args
+#?     51/push-ECX
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  write-slice-buffered/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . flush(Stderr)
+#?     # . . push args
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  flush/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+$emit-disp:check0:
+    # if (slice-empty?(word-slice)) break
+    # . EAX = slice-empty?(word-slice)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  slice-empty?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . if (EAX != 0) pass through
+    3d/compare-EAX-and  0/imm32
+    0f 85/jump-if-not-equal  $emit-disp:break/disp32
+$emit-disp:check1:
+    # if (slice-starts-with?(word-slice, "#")) break
+    # . start/EDX = word-slice->start
+    8b/copy                         0/mod/indirect  1/rm32/ECX    .           .             .           2/r32/EDX   .               .                 # copy *ECX to EDX
+    # . c/EAX = *start
+    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
+    8a/copy-byte                    0/mod/indirect  2/rm32/EDX    .           .             .           0/r32/AL    .               .                 # copy byte at *EDX to AL
+    # . if (EAX == '#') break
+    3d/compare-EAX-and  0x23/imm32/hash
+    0f 84/jump-if-equal  $emit-disp:break/disp32
+$emit-disp:check-for-disp32:
+    # if (has-metadata?(word-slice, "disp32"))
+    # . EAX = has-metadata?(ECX, "disp32")
+    # . . push args
+    68/push  "disp32"/imm32
+    51/push-ECX
+    # . . call
+    e8/call  has-metadata?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX == 0) goto next check
+    3d/compare-EAX-and  0/imm32
+    74/jump-if-equal  $emit-disp:check-for-disp16/disp8
+$emit-disp:disp32:
+    # emit(out, word-slice, 4)
+    # . . push args
+    68/push  4/imm32
+    51/push-ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  emit/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # break
+    e9/jump  $emit-disp:break/disp32
+$emit-disp:check-for-disp16:
+    # else if (has-metadata?(word-slice, "disp16"))
+    # . EAX = has-metadata?(ECX, "disp16")
+    # . . push args
+    68/push  "disp16"/imm32
+    51/push-ECX
+    # . . call
+    e8/call  has-metadata?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX == 0) goto next check
+    3d/compare-EAX-and  0/imm32
+    74/jump-if-equal  $emit-disp:check-for-disp8/disp8
+$emit-disp:disp16:
+    # emit(out, word-slice, 2)
+    # . . push args
+    68/push  2/imm32
+    51/push-ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  emit/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # break
+    e9/jump  $emit-disp:break/disp32
+$emit-disp:check-for-disp8:
+    # if (has-metadata?(word-slice, "disp8"))
+    # . EAX = has-metadata?(ECX, "disp8")
+    # . . push args
+    68/push  "disp8"/imm32
+    51/push-ECX
+    # . . call
+    e8/call  has-metadata?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX == 0) loop
+    3d/compare-EAX-and  0/imm32
+    0f 84/jump-if-equal  $emit-disp:loop/disp32
+$emit-disp:disp8:
+    # emit(out, word-slice, 1)
+    # . . push args
+    68/push  1/imm32
+    51/push-ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  emit/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # break
+$emit-disp:break:
+    # . restore locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . restore registers
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+emit-imm:  # line : (address stream byte), out : (address buffered-file) -> <void>
+    # pseudocode:
+    #   rewind-stream(line)
+    #   var word-slice = {0, 0}
+    #   while true
+    #     word-slice = next-word(line)
+    #     if (slice-empty?(word-slice)) break
+    #     if (slice-starts-with?(word-slice, "#")) break
+    #     if has-metadata?(word-slice, "imm32")
+    #       emit(out, word-slice, 4)
+    #       break
+    #     if has-metadata?(word-slice, "imm16")
+    #       emit(out, word-slice, 2)
+    #       break
+    #     if has-metadata?(word-slice, "imm8")
+    #       emit(out, word-slice, 1)
+    #       break
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+    51/push-ECX
+    52/push-EDX
+    # var word-slice/ECX = {0, 0}
+    68/push  0/imm32/end
+    68/push  0/imm32/start
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # rewind-stream(line)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  rewind-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump line {{{
+#?     # . write(2/stderr, "LL: ")
+#?     # . . push args
+#?     68/push  "LL: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, line)
+#?     # . . push args
+#?     ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+$emit-imm:loop:
+    # next-word(line, word-slice)
+    # . . push args
+    51/push-ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  next-word/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # dump word-slice {{{
+#?     # . write(2/stderr, "AA: ")
+#?     # . . push args
+#?     68/push  "AA: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . clear-stream(Stderr+4)
+#?     # . . push args
+#?     b8/copy-to-EAX  Stderr/imm32
+#?     05/add-to-EAX  4/imm32
+#?     50/push-EAX
+#?     # . . call
+#?     e8/call  clear-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . write-slice-buffered(Stderr, word-slice)
+#?     # . . push args
+#?     51/push-ECX
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  write-slice-buffered/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . flush(Stderr)
+#?     # . . push args
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  flush/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+$emit-imm:check0:
+    # if (slice-empty?(word-slice)) break
+    # . EAX = slice-empty?(word-slice)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  slice-empty?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . if (EAX != 0) pass through
+    3d/compare-EAX-and  0/imm32
+    0f 85/jump-if-not-equal  $emit-imm:break/disp32
+$emit-imm:check1:
+    # if (slice-starts-with?(word-slice, "#")) break
+    # . start/EDX = slice->start
+    8b/copy                         0/mod/indirect  1/rm32/ECX    .           .             .           2/r32/EDX   .               .                 # copy *ECX to EDX
+    # . c/EAX = *start
+    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
+    8a/copy-byte                    0/mod/indirect  2/rm32/EDX    .           .             .           0/r32/AL    .               .                 # copy byte at *EDX to AL
+    # . if (EAX == '#') break
+    3d/compare-EAX-and  0x23/imm32/hash
+    0f 84/jump-if-equal  $emit-imm:break/disp32
+$emit-imm:check-for-imm32:
+    # if (has-metadata?(word-slice, "imm32"))
+    # . EAX = has-metadata?(ECX, "imm32")
+    # . . push args
+    68/push  "imm32"/imm32
+    51/push-ECX
+    # . . call
+    e8/call  has-metadata?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX == 0) goto next check
+    3d/compare-EAX-and  0/imm32
+    74/jump-if-equal  $emit-imm:check-for-imm16/disp8
+$emit-imm:imm32:
+    # emit(out, word-slice, 4)
+    # . . push args
+    68/push  4/imm32
+    51/push-ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  emit/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # break
+    e9/jump  $emit-imm:break/disp32
+$emit-imm:check-for-imm16:
+    # if (has-metadata?(word-slice, "imm16"))
+    # . EAX = has-metadata?(ECX, "imm16")
+    # . . push args
+    68/push  "imm16"/imm32
+    51/push-ECX
+    # . . call
+    e8/call  has-metadata?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX == 0) goto next check
+    3d/compare-EAX-and  0/imm32
+    74/jump-if-equal  $emit-imm:check-for-imm8/disp8
+$emit-imm:imm16:
+    # emit(out, word-slice, 2)
+    # . . push args
+    68/push  2/imm32
+    51/push-ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  emit/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # break
+    e9/jump  $emit-imm:break/disp32
+$emit-imm:check-for-imm8:
+    # if (has-metadata?(word-slice, "imm8"))
+    # . EAX = has-metadata?(ECX, "imm8")
+    # . . push args
+    68/push  "imm8"/imm32
+    51/push-ECX
+    # . . call
+    e8/call  has-metadata?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX == 0) loop
+    3d/compare-EAX-and  0/imm32
+    0f 84/jump-if-equal  $emit-imm:loop/disp32
+$emit-imm:imm8:
+    # emit(out, word-slice, 1)
+    # . . push args
+    68/push  1/imm32
+    51/push-ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  emit/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # break
+$emit-imm:break:
+    # . restore locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . restore registers
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+emit-line-in-comment:  # line : (address stream byte), out : (address buffered-file) -> <void>
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # write-buffered(out, " # ")
+    # . . push args
+    68/push  " # "/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # write-stream-data(out, line)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write-stream-data/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+$emit-line-in-comment:end:
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-instruction-passes-comments-through:
+    # if a line starts with '#', pass it along unchanged
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "# abcd")
+    # . . push args
+    68/push  "# abcd"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-instruction(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-instruction/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check that the line just passed through
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . check-stream-equal(_test-output-stream, "# abcd", msg)
+    # . . push args
+    68/push  "F - test-convert-instruction-passes-comments-through"/imm32
+    68/push  "# abcd"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-instruction-passes-labels-through:
+    # if the first word ends with ':', pass along the entire line unchanged
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "ab: # cd")
+    # . . push args
+    68/push  "ab: # cd"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-instruction(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-instruction/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check that the line just passed through
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . check-stream-equal(_test-output-stream, "ab: # cd", msg)
+    # . . push args
+    68/push  "F - test-convert-instruction-passes-labels-through"/imm32
+    68/push  "ab: # cd"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-instruction-handles-single-opcode:
+    # if the instruction consists of a single opcode, strip its metadata and pass it along
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "ab/cd # comment")
+    # . . push args
+    68/push  "ab/cd # comment"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-instruction(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-instruction/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check output
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-stream-equal(_test-output-stream, "ab  # ab/cd # comment", msg)
+    # . . push args
+    68/push  "F - test-convert-instruction-handles-single-opcode"/imm32
+    68/push  "ab  # ab/cd # comment"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-instruction-handles-0f-opcode:
+    # if the instruction starts with 0f opcode, include a second opcode
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "0f/m1 ab/m2 # comment")
+    # . . push args
+    68/push  "0f/m1 ab/m2 # comment"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-instruction(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-instruction/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check output
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-stream-equal(_test-output-stream, "0f ab  # 0f/m1 ab/m2 # comment", msg)
+    # . . push args
+    68/push  "F - test-convert-instruction-handles-0f-opcode"/imm32
+    68/push  "0f ab  # 0f/m1 ab/m2 # comment"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-instruction-handles-f2-opcode:
+    # if the instruction starts with f2 opcode, include a second opcode
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "f2/m1 ab/m2 # comment")
+    # . . push args
+    68/push  "f2/m1 ab/m2 # comment"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-instruction(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-instruction/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check output
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-stream-equal(_test-output-stream, "f2 ab  # f2/m1 ab/m2 # comment", msg)
+    # . . push args
+    68/push  "F - test-convert-instruction-handles-f2-opcode"/imm32
+    68/push  "f2 ab  # f2/m1 ab/m2 # comment"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-instruction-handles-f3-opcode:
+    # if the instruction starts with f3 opcode, include a second opcode
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "f3/m1 ab/m2 # comment")
+    # . . push args
+    68/push  "f3/m1 ab/m2 # comment"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-instruction(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-instruction/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check output
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-stream-equal(_test-output-stream, "f3 ab  # f3/m1 ab/m2 # comment", msg)
+    # . . push args
+    68/push  "F - test-convert-instruction-handles-f3-opcode"/imm32
+    68/push  "f3 ab  # f3/m1 ab/m2 # comment"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-instruction-handles-f2-0f-opcode:
+    # if the instruction starts with f2 0f opcode, include a second opcode
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "f2/m1 0f/m2 ab/m3 # comment")
+    # . . push args
+    68/push  "f2/m1 0f/m2 ab/m3 # comment"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-instruction(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-instruction/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check output
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-stream-equal(_test-output-stream, "f2 0f ab  # f2/m1 0f/m2 ab/m3 # comment", msg)
+    # . . push args
+    68/push  "F - test-convert-instruction-handles-f2-0f-opcode"/imm32
+    68/push  "f2 0f ab  # f2/m1 0f/m2 ab/m3 # comment"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-instruction-handles-f3-0f-opcode:
+    # if the instruction starts with f3 0f opcode, include a second opcode
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "f3/m1 0f/m2 ab/m3 # comment")
+    # . . push args
+    68/push  "f3/m1 0f/m2 ab/m3 # comment"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-instruction(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-instruction/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check output
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-stream-equal(_test-output-stream, "f3 0f ab  # f3/m1 0f/m2 ab/m3 # comment", msg)
+    # . . push args
+    68/push  "F - test-convert-instruction-handles-f3-0f-opcode"/imm32
+    68/push  "f3 0f ab  # f3/m1 0f/m2 ab/m3 # comment"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-instruction-handles-unused-opcodes:
+    # if the instruction doesn't start with f2, f3 or 0f, don't include other opcodes
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "ab/m1 cd/m2 # comment")
+    # . . push args
+    68/push  "ab/m1 cd/m2 # comment"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-instruction(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-instruction/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check output
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-stream-equal(_test-output-stream, "ab  # f3/m1 0f/m2 ab/m3 # comment", msg)
+    # . . push args
+    68/push  "F - test-convert-instruction-handles-unused-opcodes"/imm32
+    68/push  "ab  # ab/m1 cd/m2 # comment"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-instruction-handles-unused-second-opcodes:
+    # if the second opcode isn't 0f, don't include further opcodes
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "f2/m1 ab/m2 cd/m3 # comment")
+    # . . push args
+    68/push  "f2/m1 ab/m2 cd/m3 # comment"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-instruction(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-instruction/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check output
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-stream-equal(_test-output-stream, "f2 ab  # f2/m1 ab/m2 cd/m3 # comment", msg)
+    # . . push args
+    68/push  "F - test-convert-instruction-handles-unused-second-opcodes"/imm32
+    68/push  "f2 ab  # f2/m1 ab/m2 cd/m3 # comment"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-instruction-handles-unused-second-opcodes-2:
+    # if the second opcode isn't 0f, don't include further opcodes
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "f3/m1 ab/m2 cd/m3 # comment")
+    # . . push args
+    68/push  "f3/m1 ab/m2 cd/m3 # comment"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-instruction(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-instruction/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check output
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-stream-equal(_test-output-stream, "f3 ab  # f3/m1 ab/m2 cd/m3 # comment", msg)
+    # . . push args
+    68/push  "F - test-convert-instruction-handles-unused-second-opcodes"/imm32
+    68/push  "f3 ab  # f3/m1 ab/m2 cd/m3 # comment"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-instruction-emits-modrm-byte:
+    # pack mod, rm32 and r32 operands into ModR/M byte
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "8b/copy 0/mod 0/rm32 1/r32")
+    # . . push args
+    68/push  "8b/copy 0/mod 0/rm32 1/r32"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-instruction(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-instruction/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check output
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-stream-equal(_test-output-stream, "8b 08  # 8b/copy 0/mod 0/rm32 1/r32", msg)
+    # . . push args
+    68/push  "F - test-convert-instruction-emits-modrm-byte"/imm32
+    68/push  "8b 08  # 8b/copy 0/mod 0/rm32 1/r32"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-instruction-emits-modrm-byte-with-non-zero-mod:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "01/add 3/mod/direct 3/rm32/EBX 1/r32/ECX")
+    # . . push args
+    68/push  "01/add 3/mod/direct 3/rm32/EBX 1/r32/ECX"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-instruction(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-instruction/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "out: ")
+#?     # . . push args
+#?     68/push  "out: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # check output
+    # . check-stream-equal(_test-output-stream, "# abcd", msg)
+    # . . push args
+    68/push  "F - test-convert-instruction-foo"/imm32
+    68/push  "01 cb  # 01/add 3/mod/direct 3/rm32/EBX 1/r32/ECX"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-instruction-emits-modrm-byte-from-subop:
+    # pack mod, rm32 and subop operands into ModR/M byte
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "ff 6/subop/push 0/mod 0/rm32")
+    # . . push args
+    68/push  "ff 6/subop/push 0/mod 0/rm32"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-instruction(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-instruction/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check output
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-stream-equal(_test-output-stream, "ff 30  # ff 6/subop/push 0/mod 0/rm32", msg)
+    # . . push args
+    68/push  "F - test-convert-instruction-emits-modrm-byte-from-subop"/imm32
+    68/push  "ff 30  # ff 6/subop/push 0/mod 0/rm32"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-instruction-emits-modrm-byte-with-missing-mod:
+    # pack rm32 and r32 operands into ModR/M byte
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "8b/copy 0/rm32 1/r32")
+    # . . push args
+    68/push  "8b/copy 0/rm32 1/r32"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-instruction(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-instruction/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check output
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-stream-equal(_test-output-stream, "8b 08  # 8b/copy 0/rm32 1/r32", msg)
+    # . . push args
+    68/push  "F - test-convert-instruction-emits-modrm-byte-with-missing-mod"/imm32
+    68/push  "8b 08  # 8b/copy 0/rm32 1/r32"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-instruction-emits-modrm-byte-with-missing-rm32:
+    # pack mod and r32 operands into ModR/M byte
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "8b/copy 0/mod 1/r32")
+    # . . push args
+    68/push  "8b/copy 0/mod 1/r32"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-instruction(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-instruction/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check output
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-stream-equal(_test-output-stream, "8b 08  # 8b/copy 0/mod 1/r32", msg)
+    # . . push args
+    68/push  "F - test-convert-instruction-emits-modrm-byte-with-missing-rm32"/imm32
+    68/push  "8b 08  # 8b/copy 0/mod 1/r32"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-instruction-emits-modrm-byte-with-missing-r32:
+    # pack mod and rm32 operands into ModR/M byte
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "8b/copy 0/mod 0/rm32")
+    # . . push args
+    68/push  "8b/copy 0/mod 0/rm32"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-instruction(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-instruction/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check output
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-stream-equal(_test-output-stream, "8b 00  # 8b/copy 0/mod 0/rm32", msg)
+    # . . push args
+    68/push  "F - test-convert-instruction-emits-modrm-byte-with-missing-r32"/imm32
+    68/push  "8b 00  # 8b/copy 0/mod 0/rm32"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-instruction-emits-sib-byte:
+    # pack base, index and scale operands into SIB byte
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "8b/copy 0/mod 4/rm32 1/r32 0/base 1/index 0/scale")
+    # . . push args
+    68/push  "8b/copy 0/mod 4/rm32 1/r32 0/base 1/index 0/scale"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-instruction(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-instruction/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check output
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-stream-equal(_test-output-stream, "8b 08  # 8b/copy 0/mod 4/rm32 1/r32 0/base 1/index 0/scale", msg)
+    # . . push args
+    68/push  "F - test-convert-instruction-emits-sib-byte"/imm32
+    68/push  "8b 0c 08  # 8b/copy 0/mod 4/rm32 1/r32 0/base 1/index 0/scale"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-instruction-emits-sib-byte-with-missing-base:
+    # pack index and scale operands into SIB byte
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "8b/copy 0/mod 4/rm32 1/r32 1/index 0/scale")
+    # . . push args
+    68/push  "8b/copy 0/mod 4/rm32 1/r32 1/index 0/scale"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-instruction(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-instruction/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check output
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-stream-equal(_test-output-stream, "8b 0c 08  # 8b/copy 0/mod 4/rm32 1/r32 1/index 0/scale", msg)
+    # . . push args
+    68/push  "F - test-convert-instruction-emits-sib-byte-with-missing-base"/imm32
+    68/push  "8b 0c 08  # 8b/copy 0/mod 4/rm32 1/r32 1/index 0/scale"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-instruction-emits-sib-byte-with-missing-index:
+    # pack base and scale operands into SIB byte
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "8b/copy 0/mod 4/rm32 1/r32 0/base 0/scale")
+    # . . push args
+    68/push  "8b/copy 0/mod 4/rm32 1/r32 0/base 0/scale"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-instruction(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-instruction/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check output
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-stream-equal(_test-output-stream, "8b 0c 08  # 8b/copy 0/mod 4/rm32 1/r32 0/base 0/scale", msg)
+    # . . push args
+    68/push  "F - test-convert-instruction-emits-sib-byte-with-missing-index"/imm32
+    68/push  "8b 0c 00  # 8b/copy 0/mod 4/rm32 1/r32 0/base 0/scale"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-instruction-emits-sib-byte-with-missing-scale:
+    # pack base and index operands into SIB byte
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "8b/copy 0/mod 4/rm32 1/r32 0/base 1/index")
+    # . . push args
+    68/push  "8b/copy 0/mod 4/rm32 1/r32 0/base 1/index"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-instruction(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-instruction/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check output
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-stream-equal(_test-output-stream, "8b 0c 08  # 8b/copy 0/mod 4/rm32 1/r32 0/base 1/index", msg)
+    # . . push args
+    68/push  "F - test-convert-instruction-emits-sib-byte-with-missing-scale"/imm32
+    68/push  "8b 0c 08  # 8b/copy 0/mod 4/rm32 1/r32 0/base 1/index"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-instruction-handles-disp32-operand:
+    # expand /disp32 operand into 4 bytes
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "e8/call 20/disp32")
+    # . . push args
+    68/push  "e8/call 20/disp32"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-instruction(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-instruction/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check output
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-stream-equal(_test-output-stream, "e8 20 00 00 00  # e8/call 20/disp32", msg)
+    # . . push args
+    68/push  "F - test-convert-instruction-handles-disp32-operand"/imm32
+    68/push  "e8 20 00 00 00  # e8/call 20/disp32"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-instruction-handles-disp16-operand:
+    # expand /disp16 operand into 2 bytes
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "e8/call 20/disp16")
+    # . . push args
+    68/push  "e8/call 20/disp16"/imm32  # not a valid instruction
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-instruction(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-instruction/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check output
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-stream-equal(_test-output-stream, "e8 20 00  # e8/call 20/disp16", msg)
+    # . . push args
+    68/push  "F - test-convert-instruction-handles-disp16-operand"/imm32
+    68/push  "e8 20 00  # e8/call 20/disp16"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-instruction-handles-disp8-operand:
+    # expand /disp8 operand into 1 byte
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "eb/jump 20/disp8")
+    # . . push args
+    68/push  "eb/jump 20/disp8"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-instruction(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-instruction/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check output
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-stream-equal(_test-output-stream, "eb 20  # eb/jump 20/disp8", msg)
+    # . . push args
+    68/push  "F - test-convert-instruction-handles-disp8-operand"/imm32
+    68/push  "eb 20  # eb/jump 20/disp8"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-instruction-handles-disp8-name:
+    # pass /disp8 name directly through
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "eb/jump xyz/disp8")
+    # . . push args
+    68/push  "eb/jump xyz/disp8"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-instruction(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-instruction/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check output
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-stream-equal(_test-output-stream, "eb xyz/disp8  # eb/jump xyz/disp8", msg)
+    # . . push args
+    68/push  "F - test-convert-instruction-handles-disp8-name"/imm32
+    68/push  "eb xyz/disp8  # eb/jump xyz/disp8"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-instruction-handles-imm32-operand:
+    # expand /imm32 operand into 4 bytes
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "68/push 0x20/imm32")
+    # . . push args
+    68/push  "68/push 0x20/imm32"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-instruction(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-instruction/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check output
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-stream-equal(_test-output-stream, "68 20 00 00 00  # 68/push 0x20/imm32", msg)
+    # . . push args
+    68/push  "F - test-convert-instruction-handles-imm32-operand"/imm32
+    68/push  "68 20 00 00 00  # 68/push 0x20/imm32"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-instruction-handles-imm16-operand:
+    # expand /imm16 operand into 2 bytes
+    # we don't have one of these at the moment, so this expands to an invalid instruction
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "68/push 0x20/imm16")
+    # . . push args
+    68/push  "68/push 0x20/imm16"/imm32  # not a valid instruction
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-instruction(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-instruction/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check output
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-stream-equal(_test-output-stream, "68 20 00  # 68/push 0x20/imm16", msg)
+    # . . push args
+    68/push  "F - test-convert-instruction-handles-imm16-operand"/imm32
+    68/push  "68 20 00  # 68/push 0x20/imm16"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-instruction-handles-imm8-operand:
+    # expand /imm8 operand into 1 byte
+    # we don't have one of these at the moment, so this expands to an invalid instruction
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "68/push 0x20/imm8")
+    # . . push args
+    68/push  "68/push 0x20/imm8"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert-instruction(_test-input-stream, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  convert-instruction/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check output
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-stream-equal(_test-output-stream, "68 20  # 68/push 0x20/imm8", msg)
+    # . . push args
+    68/push  "F - test-convert-instruction-handles-imm8-operand"/imm32
+    68/push  "68 20  # 68/push 0x20/imm8"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+# shortcut for parse-hex-int(next-token-from-slice(word->start, word->end, '/'))
+parse-datum-of-word:  # word : (address slice) -> value/EAX
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    51/push-ECX
+    56/push-ESI
+    # ESI = word
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   8/disp8         .                 # copy *(EBP+8) to ESI
+    # var slice/ECX = {0, 0}
+    68/push  0/imm32/end
+    68/push  0/imm32/start
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # slice = next-token-from-slice(word->start, word->end, '/')
+    # . . push args
+    51/push-ECX
+    68/push  0x2f/imm32/slash
+    ff          6/subop/push        1/mod/*+disp8   6/rm32/ESI    .           .             .           .           4/disp8         .                 # push *(ESI+4)
+    ff          6/subop/push        0/mod/indirect  6/rm32/ESI    .           .             .           .           .               .                 # push *ESI
+    # . . call
+    e8/call  next-token-from-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
+    # value/EAX = parse-hex-int(slice)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  parse-hex-int/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+$parse-datum-of-word:end:
+    # . reclaim locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . restore registers
+    5e/pop-to-ESI
+    59/pop-to-ECX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+# . . vim:nowrap:textwidth=0
diff --git a/apps/subx-common.subx b/apps/subx-common.subx
new file mode 100644
index 00000000..abb223fb
--- /dev/null
+++ b/apps/subx-common.subx
@@ -0,0 +1,3118 @@
+# common helpers shared by phases of the SubX translator
+
+# - some limits on the programs we can translate
+== data
+
+# maximum memory available for allocation
+Heap-size:
+  0x200000/imm32/2MB
+
+# maximum size of a single segment
+Segment-size:
+  0x80000/imm32/512KB
+
+# maximum size of input textual stream (spanning all segments)
+Input-size:
+  0x100000/imm32/1MB
+
+# maximum size of the 'labels' table in survey.subx
+Max-labels:
+  0x10000/imm32/4K-labels/64KB
+
+== code
+#   instruction                     effective address                                                   register    displacement    immediate
+# . op          subop               mod             rm32          base        index         scale       r32
+# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
+
+# - managing tables
+# SubX has rudimentary support for tables.
+#
+# Each table is a stream of rows.
+#
+# Each row consists of a 4-byte row (address to a string) and a variable-size
+# value.
+#
+# Accessing the table performs a linear scan for a key string, and always
+# requires passing in the row size.
+#
+# Table primitives:
+#   get(stream, string, row-size)
+#     aborts if not found
+#   get-or-insert(stream, string, row-size)
+#     inserts if not found
+#   get-slice(stream, slice, row-size)
+#     aborts if not found
+#   leaky-get-or-insert-slice(stream, slice, row-size)
+#     inserts if not found
+
+# 'table' is a stream of (key, value) rows
+# keys are always strings (addresses; size 4 bytes)
+# values may be any type, but rows (key+value) always occupy 'row-size' bytes
+# scan 'table' for a row with a key 'key' and return the address of the corresponding value
+# if no row is found, abort
+get:  # table : (address stream {string, _}), key : (address string), row-size : int -> EAX : (address _)
+    # pseudocode:
+    #   curr = table->data
+    #   max = &table->data[table->write]
+    #   while curr < max
+    #     if string-equal?(key, *curr)
+    #       return curr+4
+    #     curr += row-size
+    #   abort
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    51/push-ECX
+    52/push-EDX
+    56/push-ESI
+    # ESI = table
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   8/disp8         .                 # copy *(EBP+8) to ESI
+    # curr/ECX = table->data
+    8d/copy-address                 1/mod/*+disp8   6/rm32/ESI    .           .             .           1/r32/ECX   0xc/disp8       .                 # copy ESI+12 to ECX
+    # max/EDX = table->data + table->write
+    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           2/r32/EDX   .               .                 # copy *ESI to EDX
+    8d/copy-address                 0/mod/indirect  4/rm32/sib    1/base/ECX  2/index/EDX   .           2/r32/EDX   .               .                 # copy ECX+EDX to EDX
+$get:search-loop:
+    # if (curr >= max) abort
+    39/compare                      3/mod/direct    1/rm32/ECX    .           .             .           2/r32/EDX   .               .                 # compare ECX with EDX
+    73/jump-if-greater-or-equal-unsigned  $get:abort/disp8
+    # if (string-equal?(key, *curr)) return curr+4
+    # . EAX = string-equal?(key, *curr)
+    # . . push args
+    ff          6/subop/push        0/mod/indirect  1/rm32/ECX    .           .             .           .           .               .                 # push *ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  string-equal?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX != 0) return EAX = curr+4
+    3d/compare-EAX-and  0/imm32
+    74/jump-if-equal  $get:mismatch/disp8
+    8d/copy-address                 1/mod/*+disp8   1/rm32/ECX    .           .             .           0/r32/EAX   4/disp8         .                 # copy ECX+4 to EAX
+    eb/jump  $get:end/disp8
+$get:mismatch:
+    # curr += row-size
+    03/add                          1/mod/*+disp8   5/rm32/EBP    .           .             .           1/r32/ECX   0x10/disp8      .                 # add *(EBP+16) to ECX
+    # loop
+    eb/jump  $get:search-loop/disp8
+$get:end:
+    # . restore registers
+    5e/pop-to-ESI
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+$get:abort:
+    # . _write(2/stderr, error)
+    # . . push args
+    68/push  "get: key not found: "/imm32
+    68/push  2/imm32/stderr
+    # . . call
+    e8/call  _write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . _write(2/stderr, key)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    68/push  2/imm32/stderr
+    # . . call
+    e8/call  _write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . _write(2/stderr, "\n")
+    # . . push args
+    68/push  "\n"/imm32
+    68/push  2/imm32/stderr
+    # . . call
+    e8/call  _write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . syscall(exit, 1)
+    bb/copy-to-EBX  1/imm32
+    b8/copy-to-EAX  1/imm32/exit
+    cd/syscall  0x80/imm8
+    # never gets here
+
+test-get:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # - setup: create a table with a couple of keys
+    # var table/ECX : (address stream {string, number}) = stream(2 rows * 8 bytes)
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # subtract from ESP
+    68/push  0x10/imm32/length
+    68/push  0/imm32/read
+    68/push  0/imm32/write
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # insert(table, "code", 8 bytes per row)
+    # . . push args
+    68/push  8/imm32/row-size
+    68/push  "code"/imm32
+    51/push-ECX
+    # . . call
+    e8/call  get-or-insert/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # insert(table, "data", 8 bytes per row)
+    # . . push args
+    68/push  8/imm32/row-size
+    68/push  "data"/imm32
+    51/push-ECX
+    # . . call
+    e8/call  get-or-insert/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-get:check1:
+    # EAX = get(table, "code", 8 bytes per row)
+    # . . push args
+    68/push  8/imm32/row-size
+    68/push  "code"/imm32
+    51/push-ECX
+    # . . call
+    e8/call  get/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # check-ints-equal(EAX - table->data, 4, msg)
+    # . check-ints-equal(EAX - table, 16, msg)
+    # . . push args
+    68/push  "F - test-get/0"/imm32
+    68/push  0x10/imm32
+    29/subtract                     3/mod/direct    0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # subtract ECX from EAX
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-get:check2:
+    # EAX = get(table, "data", 8 bytes per row)
+    # . . push args
+    68/push  8/imm32/row-size
+    68/push  "data"/imm32
+    51/push-ECX
+    # . . call
+    e8/call  get/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # check-ints-equal(EAX - table->data, 12, msg)
+    # . check-ints-equal(EAX - table, 24, msg)
+    # . . push args
+    68/push  "F - test-get/1"/imm32
+    68/push  0x18/imm32
+    29/subtract                     3/mod/direct    0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # subtract ECX from EAX
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-get:end:
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+# 'table' is a stream of (key, value) rows
+# keys are always strings (addresses; size 4 bytes)
+# values may be any type, but rows (key+value) always occupy 'row-size' bytes
+# scan 'table' for a row with a key 'key' and return the address of the corresponding value
+# if no row is found, abort
+get-slice:  # table : (address stream {string, _}), key : (address slice), row-size : int -> EAX : (address _)
+    # pseudocode:
+    #   curr = table->data
+    #   max = &table->data[table->write]
+    #   while curr < max
+    #     if slice-equal?(key, *curr)
+    #       return curr+4
+    #     curr += row-size
+    #   abort
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    51/push-ECX
+    52/push-EDX
+    56/push-ESI
+    # ESI = table
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   8/disp8         .                 # copy *(EBP+8) to ESI
+    # curr/ECX = table->data
+    8d/copy-address                 1/mod/*+disp8   6/rm32/ESI    .           .             .           1/r32/ECX   0xc/disp8       .                 # copy ESI+12 to ECX
+    # max/EDX = table->data + table->write
+    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           2/r32/EDX   .               .                 # copy *ESI to EDX
+    8d/copy-address                 0/mod/indirect  4/rm32/sib    1/base/ECX  2/index/EDX   .           2/r32/EDX   .               .                 # copy ECX+EDX to EDX
+$get-slice:search-loop:
+    # if (curr >= max) abort
+    39/compare                      3/mod/direct    1/rm32/ECX    .           .             .           2/r32/EDX   .               .                 # compare ECX with EDX
+    73/jump-if-greater-or-equal-unsigned  $get-slice:abort/disp8
+    # if (slice-equal?(key, *curr)) return curr+4
+    # . EAX = slice-equal?(key, *curr)
+    # . . push args
+    ff          6/subop/push        0/mod/indirect  1/rm32/ECX    .           .             .           .           .               .                 # push *ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  slice-equal?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX != 0) return EAX = curr+4
+    3d/compare-EAX-and  0/imm32
+    74/jump-if-equal  $get-slice:mismatch/disp8
+    8d/copy-address                 1/mod/*+disp8   1/rm32/ECX    .           .             .           0/r32/EAX   4/disp8         .                 # copy ECX+4 to EAX
+    eb/jump  $get-slice:end/disp8
+$get-slice:mismatch:
+    # curr += row-size
+    03/add                          1/mod/*+disp8   5/rm32/EBP    .           .             .           1/r32/ECX   0x10/disp8      .                 # add *(EBP+16) to ECX
+    # loop
+    eb/jump  $get-slice:search-loop/disp8
+$get-slice:end:
+    # . restore registers
+    5e/pop-to-ESI
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+$get-slice:abort:
+    # . _write(2/stderr, error)
+    # . . push args
+    68/push  "get-slice: key not found: "/imm32
+    68/push  2/imm32/stderr
+    # . . call
+    e8/call  _write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write-slice-buffered(Stderr, key)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    68/push  Stderr/imm32
+    # . . call
+    e8/call  write-slice-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . flush(Stderr)
+    # . . push args
+    68/push  Stderr/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . _write(2/stderr, "\n")
+    # . . push args
+    68/push  "\n"/imm32
+    68/push  2/imm32/stderr
+    # . . call
+    e8/call  _write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . syscall(exit, 1)
+    bb/copy-to-EBX  1/imm32
+    b8/copy-to-EAX  1/imm32/exit
+    cd/syscall  0x80/imm8
+    # never gets here
+
+test-get-slice:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # - setup: create a table with a couple of keys
+    # var table/ECX : (address stream {string, number}) = stream(2 rows * 8 bytes)
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # subtract from ESP
+    68/push  0x10/imm32/length
+    68/push  0/imm32/read
+    68/push  0/imm32/write
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # insert(table, "code", 8 bytes per row)
+    # . . push args
+    68/push  8/imm32/row-size
+    68/push  "code"/imm32
+    51/push-ECX
+    # . . call
+    e8/call  get-or-insert/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # insert(table, "data", 8 bytes per row)
+    # . . push args
+    68/push  8/imm32/row-size
+    68/push  "data"/imm32
+    51/push-ECX
+    # . . call
+    e8/call  get-or-insert/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-get-slice:check1:
+    # (EAX..EDX) = "code"
+    b8/copy-to-EAX  "code"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           2/r32/EDX   .               .                 # copy *EAX to EDX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  2/index/EDX   .           2/r32/EDX   4/disp8         .                 # copy EAX+EDX+4 to EDX
+    05/add-to-EAX  4/imm32
+    # var slice/EDX = {EAX, EDX}
+    52/push-EDX
+    50/push-EAX
+    89/copy                         3/mod/direct    2/rm32/EDX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EDX
+    # EAX = get-slice(table, "code", 8 bytes per row)
+    # . . push args
+    68/push  8/imm32/row-size
+    52/push-EDX
+    51/push-ECX
+    # . . call
+    e8/call  get-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # check-ints-equal(EAX - table->data, 4, msg)  # first row's value slot returned
+    # . check-ints-equal(EAX - table, 16, msg)
+    # . . push args
+    68/push  "F - test-get-slice/0"/imm32
+    68/push  0x10/imm32
+    29/subtract                     3/mod/direct    0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # subtract ECX from EAX
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-get-slice:check2:
+    # (EAX..EDX) = "data"
+    b8/copy-to-EAX  "data"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           2/r32/EDX   .               .                 # copy *EAX to EDX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  2/index/EDX   .           2/r32/EDX   4/disp8         .                 # copy EAX+EDX+4 to EDX
+    05/add-to-EAX  4/imm32
+    # var slice/EDX = {EAX, EDX}
+    52/push-EDX
+    50/push-EAX
+    89/copy                         3/mod/direct    2/rm32/EDX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EDX
+    # EAX = get-slice(table, "data" slice, 8 bytes per row)
+    # . . push args
+    68/push  8/imm32/row-size
+    52/push-EDX
+    51/push-ECX
+    # . . call
+    e8/call  get-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # check-ints-equal(EAX - table->data, 12, msg)
+    # . check-ints-equal(EAX - table, 24, msg)
+    # . . push args
+    68/push  "F - test-get-slice/1"/imm32
+    68/push  0x18/imm32
+    29/subtract                     3/mod/direct    0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # subtract ECX from EAX
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-get-slice:end:
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+# 'table' is a stream of (key, value) rows
+# keys are always strings (addresses; size 4 bytes)
+# values may be any type, but rows (key+value) always occupy 'row-size' bytes
+# scan 'table' for a row with a key 'key' and return the address of the corresponding value
+# if no row is found, save 'key' to the next available row
+# if there are no rows free, abort
+# return the address of the value
+# Beware: assume keys are immutable; they're inserted by reference
+# TODO: pass in an allocation descriptor
+get-or-insert:  # table : (address stream {string, _}), key : (address string), row-size : int -> EAX : (address _)
+    # pseudocode:
+    #   curr = table->data
+    #   max = &table->data[table->write]
+    #   while curr < max
+    #     if string-equal?(key, *curr)
+    #       return curr+4
+    #     curr += row-size
+    #   if table->write >= table->length
+    #     abort
+    #   zero-out(max, row-size)
+    #   *max = key
+    #   table->write += row-size
+    #   return max+4
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    51/push-ECX
+    52/push-EDX
+    56/push-ESI
+    # ESI = table
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   8/disp8         .                 # copy *(EBP+8) to ESI
+    # curr/ECX = table->data
+    8d/copy-address                 1/mod/*+disp8   6/rm32/ESI    .           .             .           1/r32/ECX   0xc/disp8       .                 # copy ESI+12 to ECX
+    # max/EDX = table->data + table->write
+    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           2/r32/EDX   .               .                 # copy *ESI to EDX
+    8d/copy-address                 0/mod/indirect  4/rm32/sib    1/base/ECX  2/index/EDX   .           2/r32/EDX   .               .                 # copy ECX+EDX to EDX
+$get-or-insert:search-loop:
+    # if (curr >= max) break
+    39/compare                      3/mod/direct    1/rm32/ECX    .           .             .           2/r32/EDX   .               .                 # compare ECX with EDX
+    73/jump-if-greater-or-equal-unsigned  $get-or-insert:not-found/disp8
+    # if (string-equal?(key, *curr)) return curr+4
+    # . EAX = string-equal?(key, *curr)
+    # . . push args
+    ff          6/subop/push        0/mod/indirect  1/rm32/ECX    .           .             .           .           .               .                 # push *ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  string-equal?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX != 0) return EAX = curr+4
+    3d/compare-EAX-and  0/imm32
+    74/jump-if-equal  $get-or-insert:mismatch/disp8
+    8d/copy-address                 1/mod/*+disp8   1/rm32/ECX    .           .             .           0/r32/EAX   4/disp8         .                 # copy ECX+4 to EAX
+    eb/jump  $get-or-insert:end/disp8
+$get-or-insert:mismatch:
+    # curr += row-size
+    03/add                          1/mod/*+disp8   5/rm32/EBP    .           .             .           1/r32/ECX   0x10/disp8      .                 # add *(EBP+16) to ECX
+    # loop
+    eb/jump  $get-or-insert:search-loop/disp8
+$get-or-insert:not-found:
+    # result/EAX = 0
+    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
+    # if (table->write >= table->length) abort
+    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           1/r32/ECX   .               .                 # copy *ESI to ECX
+    3b/compare                      1/mod/*+disp8   6/rm32/ESI    .           .             .           1/r32/ECX   8/disp8         .                 # compare ECX with *(ESI+8)
+    73/jump-if-greater-or-equal-unsigned  $get-or-insert:abort/disp8
+    # zero-out(max, row-size)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x10/disp8      .                 # push *(EBP+16)
+    52/push-EDX
+    # . . call
+    e8/call  zero-out/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # *max = key
+    # . EAX = key
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           0/r32/EAX   0xc/disp8       .                 # copy *(EBP+12) to EAX
+    # . *max = EAX
+    89/copy                         0/mod/indirect  2/rm32/EDX    .           .             .           0/r32/EAX   .               .                 # copy EAX to *EDX
+    # table->write += row-size
+    # . EAX = row-size
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           0/r32/EAX   0x10/disp8      .                 # copy *(EBP+16) to EAX
+    # . table->write += EAX
+    01/add                          0/mod/indirect  6/rm32/ESI    .           .             .           0/r32/EAX   .               .                 # add EAX to *ESI
+    # return max+4
+    # . EAX = max
+    89/copy                         3/mod/direct    0/rm32/EAX    .           .             .           2/r32/EDX   .               .                 # copy EDX to EAX
+    # . EAX += 4
+    05/add-to-EAX  4/imm32
+$get-or-insert:end:
+    # . restore registers
+    5e/pop-to-ESI
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+$get-or-insert:abort:
+    # . _write(2/stderr, error)
+    # . . push args
+    68/push  "get-or-insert: table is full\n"/imm32
+    68/push  2/imm32/stderr
+    # . . call
+    e8/call  _write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . syscall(exit, 1)
+    bb/copy-to-EBX  1/imm32
+    b8/copy-to-EAX  1/imm32/exit
+    cd/syscall  0x80/imm8
+    # never gets here
+
+test-get-or-insert:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # var table/ECX : (address stream {string, number}) = stream(2 rows * 8 bytes)
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # subtract from ESP
+    68/push  0x10/imm32/length
+    68/push  0/imm32/read
+    68/push  0/imm32/write
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+$test-get-or-insert:first-call:
+    # - start with an empty table, insert one key, verify that it was inserted
+    # EAX = get-or-insert(table, "code", 8 bytes per row)
+    # . . push args
+    68/push  8/imm32/row-size
+    68/push  "code"/imm32
+    51/push-ECX
+    # . . call
+    e8/call  get-or-insert/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # check-ints-equal(EAX - table->data, 4, msg)  # first row's value slot returned
+    # . check-ints-equal(EAX - table, 16, msg)
+    # . . push args
+    68/push  "F - test-get-or-insert/0"/imm32
+    68/push  0x10/imm32
+    29/subtract                     3/mod/direct    0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # subtract ECX from EAX
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-get-or-insert:check2:
+    # check-ints-equal(table->write, row-size = 8, msg)
+    # . . push args
+    68/push  "F - test-get-or-insert/1"/imm32
+    68/push  8/imm32/row-size
+    ff          6/subop/push        0/mod/indirect  1/rm32/ECX    .           .             .           .           .               .                 # push *ECX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # check-string-equal(*table->data, "code", msg)
+    # . . push args
+    68/push  "F - test-get-or-insert/2"/imm32
+    68/push  "code"/imm32
+    ff          6/subop/push        1/mod/*+disp8   1/rm32/ECX    .           .             .           .           0xc/disp8       .                 # push *(ECX+12)
+    # . . call
+    e8/call  check-string-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-get-or-insert:second-call:
+    # - insert the same key again, verify that it was reused
+    # EAX = get-or-insert(table, "code", 8 bytes per row)
+    # . . push args
+    68/push  8/imm32/row-size
+    68/push  "code"/imm32
+    51/push-ECX
+    # . . call
+    e8/call  get-or-insert/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # check-ints-equal(EAX - table->data, 4, msg)
+    # . check-ints-equal(EAX - table, 16, msg)
+    # . . push args
+    68/push  "F - test-get-or-insert/3"/imm32
+    68/push  0x10/imm32
+    29/subtract                     3/mod/direct    0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # subtract ECX from EAX
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # no new row inserted
+    # . check-ints-equal(table->write, row-size = 8, msg)
+    # . . push args
+    68/push  "F - test-get-or-insert/4"/imm32
+    68/push  8/imm32/row-size
+    ff          6/subop/push        0/mod/indirect  1/rm32/ECX    .           .             .           .           .               .                 # push *ECX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # check-string-equal(*table->data, "code", msg)
+    # . . push args
+    68/push  "F - test-get-or-insert/5"/imm32
+    68/push  "code"/imm32
+    ff          6/subop/push        1/mod/*+disp8   1/rm32/ECX    .           .             .           .           0xc/disp8       .                 # push *(ECX+12)
+    # . . call
+    e8/call  check-string-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-get-or-insert:third-call:
+    # - insert a new key, verify that it was inserted
+    # EAX = get-or-insert(table, "data", 8 bytes per row)
+    # . . push args
+    68/push  8/imm32/row-size
+    68/push  "data"/imm32
+    51/push-ECX
+    # . . call
+    e8/call  get-or-insert/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # table gets a new row
+    # check-ints-equal(EAX - table->data, 12, msg)  # second row's value slot returned
+    # . check-ints-equal(EAX - table, 24, msg)
+    # . . push args
+    68/push  "F - test-get-or-insert/6"/imm32
+    68/push  0x18/imm32
+    29/subtract                     3/mod/direct    0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # subtract ECX from EAX
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # check-ints-equal(table->write, 2 rows = 16, msg)
+    # . . push args
+    68/push  "F - test-get-or-insert/7"/imm32
+    68/push  0x10/imm32/two-rows
+    ff          6/subop/push        0/mod/indirect  1/rm32/ECX    .           .             .           .           .               .                 # push *ECX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # check-string-equal(*table->data+8, "data", msg)
+    # check-string-equal(*(table+20), "data", msg)
+    # . . push args
+    68/push  "F - test-get-or-insert/8"/imm32
+    68/push  "data"/imm32
+    ff          6/subop/push        1/mod/*+disp8   1/rm32/ECX    .           .             .           .           0x14/disp8      .                 # push *(ECX+20)
+    # . . call
+    e8/call  check-string-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-get-or-insert:end:
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+# 'table' is a stream of (key, value) rows
+# keys are always strings (addresses; size 4 bytes)
+# values may be any type, but rows (key+value) always occupy 'row-size' bytes
+# scan 'table' for a row with a key 'key' and return the address of the corresponding value
+# if no row is found, save 'key' in the next available row
+# if there are no rows free, abort
+# WARNING: leaks memory
+# TODO: pass in an allocation descriptor
+leaky-get-or-insert-slice:  # table : (address stream {string, _}), key : (address slice), row-size : int -> EAX : (address _)
+    # pseudocode:
+    #   curr = table->data
+    #   max = &table->data[table->write]
+    #   while curr < max
+    #     if slice-equal?(key, *curr)
+    #       return curr+4
+    #     curr += row-size
+    #   if table->write >= table->length
+    #     abort
+    #   zero-out(max, row-size)
+    #   *max = slice-to-string(Heap, key)
+    #   table->write += row-size
+    #   return max+4
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    51/push-ECX
+    52/push-EDX
+    56/push-ESI
+    # ESI = table
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   8/disp8         .                 # copy *(EBP+8) to ESI
+    # curr/ECX = table->data
+    8d/copy-address                 1/mod/*+disp8   6/rm32/ESI    .           .             .           1/r32/ECX   0xc/disp8       .                 # copy ESI+12 to ECX
+    # max/EDX = table->data + table->write
+    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           2/r32/EDX   .               .                 # copy *ESI to EDX
+    8d/copy-address                 0/mod/indirect  4/rm32/sib    1/base/ECX  2/index/EDX   .           2/r32/EDX   .               .                 # copy ECX+EDX to EDX
+$leaky-get-or-insert-slice:search-loop:
+    # if (curr >= max) break
+    39/compare                      3/mod/direct    1/rm32/ECX    .           .             .           2/r32/EDX   .               .                 # compare ECX with EDX
+    73/jump-if-greater-or-equal-unsigned  $leaky-get-or-insert-slice:not-found/disp8
+    # if (slice-equal?(key, *curr)) return curr+4
+    # . EAX = slice-equal?(key, *curr)
+    # . . push args
+    ff          6/subop/push        0/mod/indirect  1/rm32/ECX    .           .             .           .           .               .                 # push *ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  slice-equal?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX != 0) return EAX = curr+4
+    3d/compare-EAX-and  0/imm32
+    74/jump-if-equal  $leaky-get-or-insert-slice:mismatch/disp8
+    8d/copy-address                 1/mod/*+disp8   1/rm32/ECX    .           .             .           0/r32/EAX   4/disp8         .                 # copy ECX+4 to EAX
+    eb/jump  $leaky-get-or-insert-slice:end/disp8
+$leaky-get-or-insert-slice:mismatch:
+    # curr += row-size
+    03/add                          1/mod/*+disp8   5/rm32/EBP    .           .             .           1/r32/ECX   0x10/disp8      .                 # add *(EBP+16) to ECX
+    # loop
+    eb/jump  $leaky-get-or-insert-slice:search-loop/disp8
+$leaky-get-or-insert-slice:not-found:
+    # result/EAX = 0
+    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
+    # if (table->write >= table->length) abort
+    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           1/r32/ECX   .               .                 # copy *ESI to ECX
+    3b/compare                      1/mod/*+disp8   6/rm32/ESI    .           .             .           1/r32/ECX   8/disp8         .                 # compare ECX with *(ESI+8)
+    7d/jump-if-greater-or-equal  $leaky-get-or-insert-slice:abort/disp8
+    # zero-out(max, row-size)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x10/disp8      .                 # push *(EBP+16)
+    52/push-EDX
+    # . . call
+    e8/call  zero-out/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # *max = slice-to-string(Heap, key)
+    # . EAX = slice-to-string(Heap, key)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    68/push  Heap/imm32
+    # . . call
+    e8/call  slice-to-string/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . *max = EAX
+    89/copy                         0/mod/indirect  2/rm32/EDX    .           .             .           0/r32/EAX   .               .                 # copy EAX to *EDX
+    # table->write += row-size
+    # . EAX = row-size
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           0/r32/EAX   0x10/disp8      .                 # copy *(EBP+16) to EAX
+    # . table->write += EAX
+    01/add                          0/mod/indirect  6/rm32/ESI    .           .             .           0/r32/EAX   .               .                 # add EAX to *ESI
+    # return max+4
+    # . EAX = max
+    89/copy                         3/mod/direct    0/rm32/EAX    .           .             .           2/r32/EDX   .               .                 # copy EDX to EAX
+    # . EAX += 4
+    05/add-to-EAX  4/imm32
+$leaky-get-or-insert-slice:end:
+    # . restore registers
+    5e/pop-to-ESI
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+$leaky-get-or-insert-slice:abort:
+    # . _write(2/stderr, error)
+    # . . push args
+    68/push  "leaky-get-or-insert-slice: table is full\n"/imm32
+    68/push  2/imm32/stderr
+    # . . call
+    e8/call  _write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . syscall(exit, 1)
+    bb/copy-to-EBX  1/imm32
+    b8/copy-to-EAX  1/imm32/exit
+    cd/syscall  0x80/imm8
+    # never gets here
+
+test-leaky-get-or-insert-slice:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # var table/ECX : (address stream {string, number}) = stream(2 rows * 8 bytes)
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # subtract from ESP
+    68/push  0x10/imm32/length
+    68/push  0/imm32/read
+    68/push  0/imm32/write
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # (EAX..EDX) = "code"
+    b8/copy-to-EAX  "code"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           2/r32/EDX   .               .                 # copy *EAX to EDX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  2/index/EDX   .           2/r32/EDX   4/disp8         .                 # copy EAX+EDX+4 to EDX
+    05/add-to-EAX  4/imm32
+    # var slice/EDX = {EAX, EDX}
+    52/push-EDX
+    50/push-EAX
+    89/copy                         3/mod/direct    2/rm32/EDX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EDX
+$test-leaky-get-or-insert-slice:first-call:
+    # - start with an empty table, insert one key, verify that it was inserted
+    # EAX = leaky-get-or-insert-slice(table, "code" slice, 8 bytes per row)
+    # . . push args
+    68/push  8/imm32/row-size
+    52/push-EDX
+    51/push-ECX
+    # . . call
+    e8/call  leaky-get-or-insert-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # check-ints-equal(EAX - table->data, 4, msg)  # first row's value slot returned
+    # . check-ints-equal(EAX - table, 16, msg)
+    # . . push args
+    68/push  "F - test-leaky-get-or-insert-slice/0"/imm32
+    68/push  0x10/imm32
+    29/subtract                     3/mod/direct    0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # subtract ECX from EAX
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-leaky-get-or-insert-slice:check2:
+    # check-ints-equal(table->write, row-size = 8, msg)
+    # . . push args
+    68/push  "F - test-leaky-get-or-insert-slice/1"/imm32
+    68/push  8/imm32/row-size
+    ff          6/subop/push        0/mod/indirect  1/rm32/ECX    .           .             .           .           .               .                 # push *ECX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # check-string-equal(*table->data, "code", msg)
+    # . . push args
+    68/push  "F - test-leaky-get-or-insert-slice/2"/imm32
+    68/push  "code"/imm32
+    ff          6/subop/push        1/mod/*+disp8   1/rm32/ECX    .           .             .           .           0xc/disp8       .                 # push *(ECX+12)
+    # . . call
+    e8/call  check-string-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-leaky-get-or-insert-slice:second-call:
+    # - insert the same key again, verify that it was reused
+    # EAX = leaky-get-or-insert-slice(table, "code" slice, 8 bytes per row)
+    # . . push args
+    68/push  8/imm32/row-size
+    52/push-EDX
+    51/push-ECX
+    # . . call
+    e8/call  leaky-get-or-insert-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # check-ints-equal(EAX - table->data, 4, msg)
+    # . check-ints-equal(EAX - table, 16, msg)
+    # . . push args
+    68/push  "F - test-leaky-get-or-insert-slice/3"/imm32
+    68/push  0x10/imm32
+    29/subtract                     3/mod/direct    0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # subtract ECX from EAX
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # no new row inserted
+    # . check-ints-equal(table->write, row-size = 8, msg)
+    # . . push args
+    68/push  "F - test-leaky-get-or-insert-slice/4"/imm32
+    68/push  8/imm32/row-size
+    ff          6/subop/push        0/mod/indirect  1/rm32/ECX    .           .             .           .           .               .                 # push *ECX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # check-string-equal(*table->data, "code", msg)
+    # . . push args
+    68/push  "F - test-leaky-get-or-insert-slice/5"/imm32
+    68/push  "code"/imm32
+    ff          6/subop/push        1/mod/*+disp8   1/rm32/ECX    .           .             .           .           0xc/disp8       .                 # push *(ECX+12)
+    # . . call
+    e8/call  check-string-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-leaky-get-or-insert-slice:third-call:
+    # - insert a new key, verify that it was inserted
+    # (EAX..EDX) = "data"
+    b8/copy-to-EAX  "data"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           2/r32/EDX   .               .                 # copy *EAX to EDX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  2/index/EDX   .           2/r32/EDX   4/disp8         .                 # copy EAX+EDX+4 to EDX
+    05/add-to-EAX  4/imm32
+    # var slice/EDX = {EAX, EDX}
+    52/push-EDX
+    50/push-EAX
+    89/copy                         3/mod/direct    2/rm32/EDX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EDX
+    # EAX = leaky-get-or-insert-slice(table, "data" slice, 8 bytes per row)
+    # . . push args
+    68/push  8/imm32/row-size
+    52/push-EDX
+    51/push-ECX
+    # . . call
+    e8/call  leaky-get-or-insert-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # table gets a new row
+    # check-ints-equal(EAX - table->data, 12, msg)  # second row's value slot returned
+    # . check-ints-equal(EAX - table, 24, msg)
+    # . . push args
+    68/push  "F - test-leaky-get-or-insert-slice/6"/imm32
+    68/push  0x18/imm32
+    29/subtract                     3/mod/direct    0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # subtract ECX from EAX
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # check-ints-equal(table->write, 2 rows = 16, msg)
+    # . . push args
+    68/push  "F - test-leaky-get-or-insert-slice/7"/imm32
+    68/push  0x10/imm32/two-rows
+    ff          6/subop/push        0/mod/indirect  1/rm32/ECX    .           .             .           .           .               .                 # push *ECX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # check-string-equal(*table->data+8, "data", msg)
+    # check-string-equal(*(table+20), "data", msg)
+    # . . push args
+    68/push  "F - test-leaky-get-or-insert-slice/8"/imm32
+    68/push  "data"/imm32
+    ff          6/subop/push        1/mod/*+disp8   1/rm32/ECX    .           .             .           .           0x14/disp8      .                 # push *(ECX+20)
+    # . . call
+    e8/call  check-string-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-leaky-get-or-insert-slice:end:
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+# (re)compute the bounds of the next word in the line
+# return empty string on reaching end of file
+next-word:  # line : (address stream byte), out : (address slice)
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+    51/push-ECX
+    56/push-ESI
+    57/push-EDI
+    # ESI = line
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   8/disp8         .                 # copy *(EBP+8) to ESI
+    # EDI = out
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           7/r32/EDI   0xc/disp8       .                 # copy *(EBP+12) to EDI
+    # skip-chars-matching(line, ' ')
+    # . . push args
+    68/push  0x20/imm32/space
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  skip-chars-matching/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+$next-word:check0:
+    # if (line->read >= line->write) clear out and return
+    # . EAX = line->read
+    8b/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           0/r32/EAX   4/disp8         .                 # copy *(ESI+4) to EAX
+    # . if (EAX < line->write) goto next check
+    3b/compare                      0/mod/indirect  6/rm32/ESI    .           .             .           0/r32/EAX   .               .                 # compare EAX with *ESI
+    7c/jump-if-lesser  $next-word:check-for-comment/disp8
+    # . return out = {0, 0}
+    c7          0/subop/copy        0/mod/direct    7/rm32/EDI    .           .             .           .           .               0/imm32           # copy to *EDI
+    c7          0/subop/copy        1/mod/*+disp8   7/rm32/EDI    .           .             .           .           4/disp8         0/imm32           # copy to *(EDI+4)
+    eb/jump  $next-word:end/disp8
+$next-word:check-for-comment:
+    # out->start = &line->data[line->read]
+    8b/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           1/r32/ECX   4/disp8         .                 # copy *(ESI+4) to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    6/base/ESI  1/index/ECX   .           0/r32/EAX   0xc/disp8       .                 # copy ESI+ECX+12 to EAX
+    89/copy                         0/mod/indirect  7/rm32/EDI    .           .             .           0/r32/EAX   .               .                 # copy EAX to *EDI
+    # if (line->data[line->read] == '#') out->end = &line->data[line->write]), skip rest of stream and return
+    # . EAX = line->data[line->read]
+    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
+    8a/copy-byte                    1/mod/*+disp8   4/rm32/sib    6/base/ESI  1/index/ECX   .           0/r32/AL    0xc/disp8       .                 # copy byte at *(ESI+ECX+12) to AL
+    # . compare
+    3d/compare-EAX-and  0x23/imm32/pound
+    75/jump-if-not-equal  $next-word:regular-word/disp8
+$next-word:comment:
+    # . out->end = &line->data[line->write]
+    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           0/r32/EAX   .               .                 # copy *ESI to EAX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    6/base/ESI  0/index/EAX   .           0/r32/EAX   0xc/disp8       .                 # copy ESI+EAX+12 to EAX
+    89/copy                         1/mod/*+disp8   7/rm32/EDI    .           .             .           0/r32/EAX   4/disp8         .                 # copy EAX to *(EDI+4)
+    # . line->read = line->write
+    89/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           0/r32/EAX   4/disp8         .                 # copy EAX to *(ESI+4)
+    # . return
+    eb/jump  $next-word:end/disp8
+$next-word:regular-word:
+    # otherwise skip-chars-not-matching-whitespace(line)  # including trailing newline
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  skip-chars-not-matching-whitespace/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # out->end = &line->data[line->read]
+    8b/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           1/r32/ECX   4/disp8         .                 # copy *(ESI+4) to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    6/base/ESI  1/index/ECX   .           0/r32/EAX   0xc/disp8       .                 # copy ESI+ECX+12 to EAX
+    89/copy                         1/mod/*+disp8   7/rm32/EDI    .           .             .           0/r32/EAX   4/disp8         .                 # copy EAX to *(EDI+4)
+$next-word:end:
+    # . restore registers
+    5f/pop-to-EDI
+    5e/pop-to-ESI
+    59/pop-to-ECX
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-next-word:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-stream)
+    # . . push args
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # var slice/ECX = {0, 0}
+    68/push  0/imm32/end
+    68/push  0/imm32/start
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # write(_test-stream, "  ab")
+    # . . push args
+    68/push  "  ab"/imm32
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # next-word(_test-stream, slice)
+    # . . push args
+    51/push-ECX
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  next-word/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check-ints-equal(slice->start - _test-stream->data, 2, msg)
+    # . check-ints-equal(slice->start - _test-stream, 14, msg)
+    # . . push args
+    68/push  "F - test-next-word: start"/imm32
+    68/push  0xe/imm32
+    # . . push slice->start - _test-stream
+    8b/copy                         0/mod/indirect  1/rm32/ECX    .           .             .           0/r32/EAX   .               .                 # copy *ECX to EAX
+    81          5/subop/subtract    3/mod/direct    0/rm32/EAX    .           .             .           .           .               _test-stream/imm32 # subtract from EAX
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # check-ints-equal(slice->end - _test-stream->data, 4, msg)
+    # . check-ints-equal(slice->end - _test-stream, 16, msg)
+    # . . push args
+    68/push  "F - test-next-word: end"/imm32
+    68/push  0x10/imm32
+    # . . push slice->end - _test-stream
+    8b/copy                         1/mod/*+disp8   1/rm32/ECX    .           .             .           0/r32/EAX   4/disp8         .                 # copy *(ECX+4) to EAX
+    81          5/subop/subtract    3/mod/direct    0/rm32/EAX    .           .             .           .           .               _test-stream/imm32 # subtract from EAX
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-next-word-returns-whole-comment:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-stream)
+    # . . push args
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # var slice/ECX = {0, 0}
+    68/push  0/imm32/end
+    68/push  0/imm32/start
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # write(_test-stream, "  # a")
+    # . . push args
+    68/push  "  # a"/imm32
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # next-word(_test-stream, slice)
+    # . . push args
+    51/push-ECX
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  next-word/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check-ints-equal(slice->start - _test-stream->data, 2, msg)
+    # . check-ints-equal(slice->start - _test-stream, 14, msg)
+    # . . push args
+    68/push  "F - test-next-word-returns-whole-comment: start"/imm32
+    68/push  0xe/imm32
+    # . . push slice->start - _test-stream
+    8b/copy                         0/mod/indirect  1/rm32/ECX    .           .             .           0/r32/EAX   .               .                 # copy *ECX to EAX
+    81          5/subop/subtract    3/mod/direct    0/rm32/EAX    .           .             .           .           .               _test-stream/imm32 # subtract from EAX
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # check-ints-equal(slice->end - _test-stream->data, 5, msg)
+    # . check-ints-equal(slice->end - _test-stream, 17, msg)
+    # . . push args
+    68/push  "F - test-next-word-returns-whole-comment: end"/imm32
+    68/push  0x11/imm32
+    # . . push slice->end - _test-stream
+    8b/copy                         1/mod/*+disp8   1/rm32/ECX    .           .             .           0/r32/EAX   4/disp8         .                 # copy *(ECX+4) to EAX
+    81          5/subop/subtract    3/mod/direct    0/rm32/EAX    .           .             .           .           .               _test-stream/imm32 # subtract from EAX
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-next-word-returns-empty-string-on-eof:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-stream)
+    # . . push args
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # var slice/ECX = {0, 0}
+    68/push  0/imm32/end
+    68/push  0/imm32/start
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # write nothing to _test-stream
+    # next-word(_test-stream, slice)
+    # . . push args
+    51/push-ECX
+    68/push  _test-stream/imm32
+    # . . call
+    e8/call  next-word/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check-ints-equal(slice->end - slice->start, 0, msg)
+    # . . push args
+    68/push  "F - test-next-word-returns-empty-string-on-eof"/imm32
+    68/push  0/imm32
+    # . . push slice->end - slice->start
+    8b/copy                         1/mod/*+disp8   1/rm32/ECX    .           .             .           0/r32/EAX   4/disp8         .                 # copy *(ECX+4) to EAX
+    2b/subtract                     0/mod/indirect  1/rm32/ECX    .           .             .           0/r32/EAX   .               .                 # subtract *ECX from EAX
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+# write an entire stream's contents to a buffered-file
+# ways to do this:
+#   - construct a 'maximal slice' and pass it to write-slice-buffered
+#   - flush the buffered-file and pass the stream directly to its fd (disabling buffering)
+# we'll go with the first way for now
+write-stream-data:  # f : (address buffered-file), s : (address stream) -> <void>
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+    51/push-ECX
+    56/push-ESI
+    # ESI = s
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   0xc/disp8       .                 # copy *(EBP+12) to ESI
+    # var slice/ECX = {s->data, s->data + s->write}
+    # . push s->data + s->write
+    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           0/r32/EAX   .               .                 # copy *ESI to EAX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    6/base/ESI  0/index/EAX   .           0/r32/EAX   0xc/disp8       .                 # copy ESI+EAX+12 to EAX
+    50/push-EAX
+    # . push s->data
+    8d/copy-address                 1/mod/*+disp8   6/rm32/ESI    .           .             .           0/r32/EAX   0xc/disp8       .                 # copy ESI+12 to EAX
+    50/push-EAX
+    # . ECX = ESP
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # write-slice-buffered(f, slice)
+    # . . push args
+    51/push-ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  write-slice-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+$write-stream-data:end:
+    # . restore locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . restore registers
+    5e/pop-to-ESI
+    59/pop-to-ECX
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-write-stream-data:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "abcd")
+    # . . push args
+    68/push  "abcd"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # write-stream-data(_test-output-buffered-file, _test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  write-stream-data/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check that the write happened as expected
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . check-stream-equal(_test-output-stream, "abcd", msg)
+    # . . push args
+    68/push  "F - test-write-stream-data"/imm32
+    68/push  "abcd"/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+has-metadata?:  # word : (address slice), s : (address string) -> EAX : boolean
+    # pseudocode:
+    #   var twig : &slice = next-token-from-slice(word->start, word->end, '/')  # skip name
+    #   curr = twig->end
+    #   while true
+    #     twig = next-token-from-slice(curr, word->end, '/')
+    #     if (twig.empty()) break
+    #     if (slice-equal?(twig, s)) return true
+    #     curr = twig->end
+    #   return false
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    51/push-ECX
+    52/push-EDX
+    56/push-ESI
+    57/push-EDI
+    # ESI = word
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   8/disp8         .                 # copy *(EBP+8) to ESI
+    # EDX = word->end
+    8b/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           2/r32/EDX   4/disp8         .                 # copy *(ESI+4) to EDX
+    # var twig/EDI : (address slice) = {0, 0}
+    68/push  0/imm32/end
+    68/push  0/imm32/start
+    89/copy                         3/mod/direct    7/rm32/EDI    .           .             .           4/r32/ESP   .               .                 # copy ESP to EDI
+    # next-token-from-slice(word->start, word->end, '/', twig)
+    # . . push args
+    57/push-EDI
+    68/push  0x2f/imm32/slash
+    52/push-EDX
+    ff          6/subop/push        0/mod/indirect  6/rm32/ESI    .           .             .           .           .               .                 # push *ESI
+    # . . call
+    e8/call  next-token-from-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
+    # curr/ECX = twig->end
+    8b/copy                         1/mod/*+disp8   7/rm32/EDI    .           .             .           1/r32/ECX   4/disp8         .                 # copy *(EDI+4) to ECX
+$has-metadata?:loop:
+    # next-token-from-slice(curr, word->end, '/', twig)
+    # . . push args
+    57/push-EDI
+    68/push  0x2f/imm32/slash
+    52/push-EDX
+    51/push-ECX
+    # . . call
+    e8/call  next-token-from-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
+    # if (slice-empty?(twig)) return false
+    # . EAX = slice-empty?(twig)
+    # . . push args
+    57/push-EDI
+    # . . call
+    e8/call  slice-empty?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . if (EAX != 0) return false
+    3d/compare-EAX-and  0/imm32
+    75/jump-if-not-equal  $has-metadata?:false/disp8
+    # if (slice-equal?(twig, s)) return true
+    # . EAX = slice-equal?(twig, s)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    57/push-EDI
+    # . . call
+    e8/call  slice-equal?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX != 0) return true
+    3d/compare-EAX-and  0/imm32
+    75/jump-if-not-equal  $has-metadata?:true/disp8
+    # curr = twig->end
+    8b/copy                         1/mod/*+disp8   7/rm32/EDI    .           .             .           1/r32/ECX   4/disp8         .                 # copy *(EDI+4) to ECX
+    eb/jump  $has-metadata?:loop/disp8
+$has-metadata?:true:
+    b8/copy-to-EAX  1/imm32/true
+    eb/jump  $has-metadata?:end/disp8
+$has-metadata?:false:
+    b8/copy-to-EAX  0/imm32/false
+$has-metadata?:end:
+    # . reclaim locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . restore registers
+    5f/pop-to-EDI
+    5e/pop-to-ESI
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-has-metadata-true:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # (EAX..ECX) = "ab/imm32"
+    b8/copy-to-EAX  "ab/imm32"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # var in/ESI : (address slice) = {EAX, ECX}
+    51/push-ECX
+    50/push-EAX
+    89/copy                         3/mod/direct    6/rm32/ESI    .           .             .           4/r32/ESP   .               .                 # copy ESP to ESI
+    # EAX = has-metadata?(ESI, "imm32")
+    # . . push args
+    68/push  "imm32"/imm32
+    56/push-ESI
+    # . . call
+    e8/call  has-metadata?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check-ints-equal(EAX, 1, msg)
+    # . . push args
+    68/push  "F - test-has-metadata-true"/imm32
+    68/push  1/imm32/true
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-has-metadata-false:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # (EAX..ECX) = "ab/c"
+    b8/copy-to-EAX  "ab/c"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # var in/ESI : (address slice) = {EAX, ECX}
+    51/push-ECX
+    50/push-EAX
+    89/copy                         3/mod/direct    6/rm32/ESI    .           .             .           4/r32/ESP   .               .                 # copy ESP to ESI
+    # EAX = has-metadata?(ESI, "d")
+    # . . push args
+    68/push  "d"/imm32
+    56/push-ESI
+    # . . call
+    e8/call  has-metadata?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check-ints-equal(EAX, 0, msg)
+    # . . push args
+    68/push  "F - test-has-metadata-false"/imm32
+    68/push  0/imm32/false
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-has-metadata-ignore-name:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # (EAX..ECX) = "a/b"
+    b8/copy-to-EAX  "a/b"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # var in/ESI : (address slice) = {EAX, ECX}
+    51/push-ECX
+    50/push-EAX
+    89/copy                         3/mod/direct    6/rm32/ESI    .           .             .           4/r32/ESP   .               .                 # copy ESP to ESI
+    # EAX = has-metadata?(ESI, "a")
+    # . . push args
+    68/push  "a"/imm32
+    56/push-ESI
+    # . . call
+    e8/call  has-metadata?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check-ints-equal(EAX, 0, msg)
+    # . . push args
+    68/push  "F - test-has-metadata-ignore-name"/imm32
+    68/push  0/imm32/false
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-has-metadata-multiple-true:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # (EAX..ECX) = "a/b/c"
+    b8/copy-to-EAX  "a/b/c"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # var in/ESI : (address slice) = {EAX, ECX}
+    51/push-ECX
+    50/push-EAX
+    89/copy                         3/mod/direct    6/rm32/ESI    .           .             .           4/r32/ESP   .               .                 # copy ESP to ESI
+    # EAX = has-metadata?(ESI, "c")
+    # . . push args
+    68/push  "c"/imm32
+    56/push-ESI
+    # . . call
+    e8/call  has-metadata?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check-ints-equal(EAX, 1, msg)
+    # . . push args
+    68/push  "F - test-has-metadata-multiple-true"/imm32
+    68/push  1/imm32/true
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-has-metadata-multiple-false:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # (EAX..ECX) = "a/b/c"
+    b8/copy-to-EAX  "a/b/c"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # var in/ESI : (address slice) = {EAX, ECX}
+    51/push-ECX
+    50/push-EAX
+    89/copy                         3/mod/direct    6/rm32/ESI    .           .             .           4/r32/ESP   .               .                 # copy ESP to ESI
+    # EAX = has-metadata?(ESI, "d")
+    # . . push args
+    68/push  "d"/imm32
+    56/push-ESI
+    # . . call
+    e8/call  has-metadata?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check-ints-equal(EAX, 0, msg)
+    # . . push args
+    68/push  "F - test-has-metadata-multiple-false"/imm32
+    68/push  0/imm32/false
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+# If datum of 'word' is not a valid name, it must be a hex int. Parse and print
+# it in 'width' bytes of hex, least significant first.
+# Otherwise just print the entire word including metadata.
+# Always print a trailing space.
+emit:  # out : (address buffered-file), word : (address slice), width : int -> <void>
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+    56/push-ESI
+    57/push-EDI
+    # ESI = word
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   0xc/disp8       .                 # copy *(EBP+12) to ESI
+    # var name/EDI : (address slice) = {0, 0}
+    68/push  0/imm32/end
+    68/push  0/imm32/start
+    89/copy                         3/mod/direct    7/rm32/EDI    .           .             .           4/r32/ESP   .               .                 # copy ESP to EDI
+    # datum = next-token-from-slice(word->start, word->end, '/')
+    # . . push args
+    57/push-EDI
+    68/push  0x2f/imm32/slash
+    ff          6/subop/push        1/mod/*+disp8   6/rm32/ESI    .           .             .           .           4/disp8         .                 # push *(ESI+4)
+    ff          6/subop/push        0/mod/indirect  6/rm32/ESI    .           .             .           .           .               .                 # push *ESI
+    # . . call
+    e8/call  next-token-from-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
+    # if (is-valid-name?(datum)) write-slice-buffered(out, word) and return
+    # . EAX = is-valid-name?(name)
+    # . . push args
+    57/push-EDI
+    # . . call
+    e8/call  is-valid-name?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . if (EAX != 0)
+    3d/compare-EAX-and  0/imm32
+    74/jump-if-equal  $emit:hex-int/disp8
+$emit:name:
+    # . write-slice-buffered(out, word)
+    # . . push args
+    56/push-ESI
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  write-slice-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write-buffered(out, " ")
+    # . . push args
+    68/push  " "/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  write-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . return
+    eb/jump  $emit:end/disp8
+    # otherwise emit-hex(out, parse-hex-int(datum), width)
+    #   (Weird shit can happen here if the datum of 'word' isn't either a valid
+    #   name or a hex number, but we're only going to be passing in real legal
+    #   programs. We just want to make sure that valid names aren't treated as
+    #   (valid) hex numbers.)
+$emit:hex-int:
+    # . value/EAX = parse-hex-int(datum)
+    # . . push args
+    57/push-EDI
+    # . . call
+    e8/call  parse-hex-int/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . emit-hex(out, value, width)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x10/disp8      .                 # push *(EBP+16)
+    50/push-EAX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  emit-hex/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$emit:end:
+    # . reclaim locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . restore registers
+    5f/pop-to-EDI
+    5e/pop-to-ESI
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-emit-number:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # (EAX..ECX) = "30"
+    b8/copy-to-EAX  "30"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # var slice/ECX = {EAX, ECX}
+    51/push-ECX
+    50/push-EAX
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # emit(_test-output-buffered-file, slice, 1)
+    # . . push args
+    68/push  1/imm32
+    51/push-ECX
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  emit/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-stream-equal(_test-output-stream, "30 ", msg)
+    # . . push args
+    68/push  "F - test-emit-number/1"/imm32
+    68/push  "30 "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-emit-negative-number:
+    # test support for sign-extending negative numbers
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # (EAX..ECX) = "-2"
+    b8/copy-to-EAX  "-2"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # var slice/ECX = {EAX, ECX}
+    51/push-ECX
+    50/push-EAX
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # emit(_test-output-buffered-file, slice, 2)
+    # . . push args
+    68/push  2/imm32
+    51/push-ECX
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  emit/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-stream-equal(_test-output-stream, "fe ff ", msg)
+    # . . push args
+    68/push  "F - test-emit-number/1"/imm32
+    68/push  "fe ff "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-emit-number-with-metadata:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # (EAX..ECX) = "-2/foo"
+    b8/copy-to-EAX  "-2/foo"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # var slice/ECX = {EAX, ECX}
+    51/push-ECX
+    50/push-EAX
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # emit(_test-output-buffered-file, slice, 2)
+    # . . push args
+    68/push  2/imm32
+    51/push-ECX
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  emit/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # the '/foo' will have no impact on the output
+    # check-stream-equal(_test-output-stream, "fe ff ", msg)
+    # . . push args
+    68/push  "F - test-emit-number-with-metadata"/imm32
+    68/push  "fe ff "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-emit-non-number:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # (EAX..ECX) = "xyz"
+    b8/copy-to-EAX  "xyz"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # var slice/ECX = {EAX, ECX}
+    51/push-ECX
+    50/push-EAX
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # emit(_test-output-buffered-file, slice, 2)
+    # . . push args
+    68/push  2/imm32
+    51/push-ECX
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  emit/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-stream-equal(_test-output-stream, "xyz", msg)
+    # . . push args
+    68/push  "F - test-emit-non-number"/imm32
+    68/push  "xyz "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-emit-non-number-with-metadata:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # (EAX..ECX) = "xyz/"
+    b8/copy-to-EAX  "xyz/"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # var slice/ECX = {EAX, ECX}
+    51/push-ECX
+    50/push-EAX
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # emit(_test-output-buffered-file, slice, 2)
+    # . . push args
+    68/push  2/imm32
+    51/push-ECX
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  emit/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-stream-equal(_test-output-stream, "xyz/", msg)
+    # . . push args
+    68/push  "F - test-emit-non-number-with-metadata"/imm32
+    68/push  "xyz/ "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-emit-non-number-with-all-hex-digits-and-metadata:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # (EAX..ECX) = "abcd/xyz"
+    b8/copy-to-EAX  "abcd/xyz"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # var slice/ECX = {EAX, ECX}
+    51/push-ECX
+    50/push-EAX
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # emit(_test-output-buffered-file, slice, 2)
+    # . . push args
+    68/push  2/imm32
+    51/push-ECX
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  emit/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # check-stream-equal(_test-output-stream, "abcd/xyz")
+    # . . push args
+    68/push  "F - test-emit-non-number-with-all-hex-digits"/imm32
+    68/push  "abcd/xyz "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+# conditions for 'valid' names that are not at risk of looking like hex numbers
+# keep in sync with the rules in labels.cc
+#: - if it starts with a digit, it's treated as a number. If it can't be
+#:   parsed as hex it will raise an error.
+#: - if it starts with '-' it's treated as a number.
+#: - if it starts with '0x' it's treated as a number. (redundant)
+#: - if it's two characters long, it can't be a name. Either it's a hex
+#:   byte, or it raises an error.
+is-valid-name?:  # in : (address slice) -> EAX : boolean
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    51/push-ECX
+    56/push-ESI
+    # ESI = in
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   8/disp8         .                 # copy *(EBP+8) to ESI
+    # start/ECX = in->start
+    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           1/r32/ECX   .               .                 # copy *ESI to ECX
+    # end/EAX = in->end
+    8b/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           0/r32/EAX   4/disp8         .                 # copy *(ESI+4) to EAX
+$is-valid-name?:check0:
+    # if (start >= end) return false
+    39/compare                      3/mod/direct    1/rm32/ECX    .           .             .           0/r32/EAX   .               .                 # compare ECX with EAX
+    73/jump-if-greater-or-equal-unsigned  $is-valid-name?:false/disp8
+$is-valid-name?:check1:
+    # EAX -= ECX
+    29/subtract                     3/mod/direct    0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # subtract ECX from EAX
+    # if (EAX == 2) return false
+    3d/compare-EAX-and  2/imm32
+    74/jump-if-equal  $is-valid-name?:false/disp8
+$is-valid-name?:check2:
+    # c/EAX = *ECX
+    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
+    8a/copy-byte                    0/mod/indirect  1/rm32/ECX    .           .             .           0/r32/AL    .               .                 # copy byte at *ECX to AL
+    # if (c == "-") return false
+    3d/compare-EAX-and  2d/imm32/-
+    74/jump-if-equal  $is-valid-name?:false/disp8
+$is-valid-name?:check3a:
+    # if (c < "0") return true
+    3d/compare-EAX-with  30/imm32/0
+    7c/jump-if-lesser  $is-valid-name?:true/disp8
+$is-valid-name?:check3b:
+    # if (c > "9") return true
+    3d/compare-EAX-with  39/imm32/9
+    7f/jump-if-greater  $is-valid-name?:true/disp8
+$is-valid-name?:false:
+    # return false
+    b8/copy-to-EAX  0/imm32/false
+    eb/jump  $is-valid-name?:end/disp8
+$is-valid-name?:true:
+    # return true
+    b8/copy-to-EAX  1/imm32/true
+$is-valid-name?:end:
+    # . restore registers
+    5e/pop-to-ESI
+    59/pop-to-ECX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-is-valid-name-digit-prefix:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # (EAX..ECX) = "34"
+    b8/copy-to-EAX  "34"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # var slice/ECX = {EAX, ECX}
+    51/push-ECX
+    50/push-EAX
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # EAX = is-valid-name?(slice)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  is-valid-name?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-ints-equal(EAX, 0, msg)
+    # . . push args
+    68/push  "F - test-is-valid-name-digit-prefix"/imm32
+    68/push  0/imm32/false
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-is-valid-name-negative-prefix:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # (EAX..ECX) = "-0x34"
+    b8/copy-to-EAX  "-0x34"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # var slice/ECX = {EAX, ECX}
+    51/push-ECX
+    50/push-EAX
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # EAX = is-valid-name?(slice)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  is-valid-name?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-ints-equal(EAX, 0, msg)
+    # . . push args
+    68/push  "F - test-is-valid-name-negative-prefix"/imm32
+    68/push  0/imm32/false
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-is-valid-name-0x-prefix:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # (EAX..ECX) = "0x34"
+    b8/copy-to-EAX  "0x34"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # var slice/ECX = {EAX, ECX}
+    51/push-ECX
+    50/push-EAX
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # EAX = is-valid-name?(slice)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  is-valid-name?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-ints-equal(EAX, 0, msg)
+    # . . push args
+    68/push  "F - test-is-valid-name-0x-prefix"/imm32
+    68/push  0/imm32/false
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-is-valid-name-starts-with-pre-digit:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # (EAX..ECX) = "/03"
+    b8/copy-to-EAX  "/03"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # var slice/ECX = {EAX, ECX}
+    51/push-ECX
+    50/push-EAX
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # EAX = is-valid-name?(slice)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  is-valid-name?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-ints-equal(EAX, 1, msg)
+    # . . push args
+    68/push  "F - test-is-valid-name-starts-with-pre-digit"/imm32
+    68/push  1/imm32/true
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-is-valid-name-starts-with-post-digit:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # (EAX..ECX) = "q34"
+    b8/copy-to-EAX  "q34"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # var slice/ECX = {EAX, ECX}
+    51/push-ECX
+    50/push-EAX
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # EAX = is-valid-name?(slice)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  is-valid-name?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-ints-equal(EAX, 1, msg)
+    # . . push args
+    68/push  "F - test-is-valid-name-starts-with-post-digit"/imm32
+    68/push  1/imm32/true
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-is-valid-name-starts-with-digit:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # (EAX..ECX) = "0x34"
+    b8/copy-to-EAX  "0x34"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # var slice/ECX = {EAX, ECX}
+    51/push-ECX
+    50/push-EAX
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # EAX = is-valid-name?(slice)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  is-valid-name?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-ints-equal(EAX, 0, msg)
+    # . . push args
+    68/push  "F - test-is-valid-name-starts-with-digit"/imm32
+    68/push  0/imm32/false
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+# print 'n' in hex in 'width' bytes in lower-endian order, with a space after every byte
+emit-hex:  # out : (address buffered-file), n : int, width : int -> <void>
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+    51/push-ECX
+    52/push-EDX
+    53/push-EBX
+    57/push-EDI
+    # EDI = out
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           7/r32/EDI   8/disp8         .                 # copy *(EBP+8) to EDI
+    # EBX = n
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           3/r32/EBX   0xc/disp8       .                 # copy *(EBP+12) to EBX
+    # EDX = width
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           2/r32/EDX   0x10/disp8      .                 # copy *(EBP+16) to EDX
+    # var curr/ECX = 0
+    31/xor                          3/mod/direct    1/rm32/ECX    .           .             .           1/r32/ECX   .               .                 # clear ECX
+$emit-hex:loop:
+    # if (curr >= width) break
+    39/compare                      3/mod/direct    1/rm32/ECX    .           .             .           2/r32/EDX   .               .                 # compare ECX with EDX
+    7d/jump-if-greater-or-equal  $emit-hex:end/disp8
+    # print-byte-buffered(out, EBX)
+    # . . push args
+    53/push-EBX
+    57/push-EDI
+    # . . call
+    e8/call  print-byte-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # write-byte-buffered(out, ' ')
+    # . . push args
+    68/push  0x20/imm32/space
+    57/push-EDI
+    # . . call
+    e8/call  write-byte-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # EBX = EBX >> 8
+    c1/shift    5/subop/logic-right 3/mod/direct    3/rm32/EBX    .           .             .           .           .               8/imm8            # shift EBX right by 8 bits, while padding zeroes
+$emit-hex:continue:
+    # ++curr
+    41/increment-ECX
+    eb/jump  $emit-hex:loop/disp8
+$emit-hex:end:
+    # . restore registers
+    5f/pop-to-EDI
+    5b/pop-to-EBX
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-emit-hex-single-byte:
+    # setup
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # emit-hex(_test-output-buffered-file, 0xab, 1)
+    # . . push args
+    68/push  1/imm32
+    68/push  0xab/imm32
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  emit-hex/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-ints-equal(*_test-output-stream->data, 'ab ', msg)
+    # . . push args
+    68/push  "F - test-emit-hex-single-byte"/imm32
+    68/push  0x206261/imm32
+    # . . push *_test-output-stream->data
+    b8/copy-to-EAX  _test-output-stream/imm32
+    ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           0xc/disp8       .                 # push *(EAX+12)
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . end
+    c3/return
+
+test-emit-hex-multiple-byte:
+    # setup
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # emit-hex(_test-output-buffered-file, 0x1234, 2)
+    # . . push args
+    68/push  2/imm32
+    68/push  0x1234/imm32
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  emit-hex/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-stream-equal(_test-output-stream, "34 12 ", msg)
+    # . . push args
+    68/push  "F - test-emit-hex-multiple-byte/1"/imm32
+    68/push  "34 12 "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . end
+    c3/return
+
+test-emit-hex-zero-pad:
+    # setup
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # emit-hex(_test-output-buffered-file, 0xab, 2)
+    # . . push args
+    68/push  2/imm32
+    68/push  0xab/imm32
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  emit-hex/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check(_test-output-stream->data == 'ab 00 ')
+    # . . push args
+    68/push  "F - test-emit-hex-zero-pad/1"/imm32
+    68/push  "ab 00 "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . end
+    c3/return
+
+test-emit-hex-negative:
+    # setup
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # emit-hex(_test-output-buffered-file, -1, 2)
+    # . . push args
+    68/push  2/imm32
+    68/push  -1/imm32
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  emit-hex/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-stream-equal(_test-output-stream == "ff ff ")
+    # . . push args
+    68/push  "F - test-emit-hex-negative/1"/imm32
+    68/push  "ff ff "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-stream-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . end
+    c3/return
+
+# print 'arr' in hex with a space after every byte
+emit-hex-array:  # out : (address buffered-file), arr : (address array byte) -> <void>
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+    51/push-ECX
+    52/push-EDX
+    57/push-EDI
+    # EDI = out
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           7/r32/EDI   8/disp8         .                 # copy *(EBP+8) to EDI
+    # EDX = arr  # <== 0xbdffffe4
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           2/r32/EDX   0xc/disp8       .                 # copy *(EBP+12) to EDX
+    # curr/ECX = arr->data
+    8d/copy-address                 1/mod/*+disp8   2/rm32/EDX    .           .             .           1/r32/ECX   4/disp8         .                 # copy EDX+4 to ECX
+    # max/EDX = arr->data + arr->length
+    8b/copy                         0/mod/indirect  2/rm32/EDX    .           .             .           2/r32/EDX   .               .                 # copy *EDX to EDX
+    01/add                          3/mod/direct    2/rm32/EDX    .           .             .           1/r32/ECX   .               .                 # add ECX to EDX
+    # EAX = 0
+    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
+$emit-hex-array:loop:
+    # if (curr >= width) break
+    39/compare                      3/mod/direct    1/rm32/ECX    .           .             .           2/r32/EDX   .               .                 # compare ECX with EDX
+    73/jump-if-greater-or-equal-unsigned  $emit-hex-array:end/disp8
+    # emit-hex(out, *curr, width=1)
+    # . . push args
+    68/push  1/imm32/width
+    8a/copy-byte                    0/mod/indirect  1/rm32/ECX    .           .             .           0/r32/AL    .               .                 # copy byte at *ECX to AL
+    50/push-EAX
+    57/push-EDI
+    # . . call
+    e8/call  emit-hex/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # ++curr
+    41/increment-ECX
+    eb/jump  $emit-hex-array:loop/disp8
+$emit-hex-array:end:
+    # . restore registers
+    5f/pop-to-EDI
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-emit-hex-array:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # var arr/ECX (address array byte) = [01, 02, 03]
+    68/push  0x00030201/imm32  # bytes 01 02 03
+    68/push  3/imm32/length
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # emit-hex-array(_test-output-buffered-file, arr)
+    # . . push args
+    51/push-ECX
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  emit-hex-array/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "result: ^")
+#?     # . . push args
+#?     68/push  "result: ^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . rewind-stream(_test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     # . . call
+#?     e8/call  rewind-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # }}}
+    # check-next-stream-line-equal(_test-output-stream, "01 02 03 ", msg)
+    # . . push args
+    68/push  "F - test-emit-hex-array"/imm32
+    68/push  "01 02 03 "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+compute-width: # word : (address array byte) -> EAX : int
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    51/push-ECX
+    # EAX = word
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           0/r32/EAX   8/disp8         .                 # copy *(EBP+8) to ECX
+    # ECX = word + word->length
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    # EAX = word->data
+    05/add-to-EAX  4/imm32
+    # var in/ECX : (address slice) = {EAX, ECX}
+    51/push-ECX
+    50/push-EAX
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # return compute-width-of-slice(ECX)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  compute-width-of-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+$compute-width:end:
+    # . reclaim locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . restore registers
+    59/pop-to-ECX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+compute-width-of-slice: # s : (address slice) -> EAX : int
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    51/push-ECX
+    # ECX = s
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           1/r32/ECX   8/disp8         .                 # copy *(EBP+8) to ECX
+    # if (has-metadata?(word, "imm32")) return 4
+    # . EAX = has-metadata?(word, "imm32")
+    # . . push args
+    68/push  "imm32"/imm32
+    51/push-ECX
+    # . . call
+    e8/call  has-metadata?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX != 0) return 4
+    3d/compare-EAX-and  0/imm32
+    b8/copy-to-EAX  4/imm32         # ZF is set, so we can overwrite EAX now
+    75/jump-if-not-equal  $compute-width-of-slice:end/disp8
+    # if (has-metadata?(word, "disp32")) return 4
+    # . EAX = has-metadata?(word, "disp32")
+    # . . push args
+    68/push  "disp32"/imm32
+    51/push-ECX
+    # . . call
+    e8/call  has-metadata?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX != 0) return 4
+    3d/compare-EAX-and  0/imm32
+    b8/copy-to-EAX  4/imm32         # ZF is set, so we can overwrite EAX now
+    75/jump-if-not-equal  $compute-width-of-slice:end/disp8
+    # if (has-metadata?(word, "imm16")) return 2
+    # . EAX = has-metadata?(word, "imm16")
+    # . . push args
+    68/push  "imm16"/imm32
+    51/push-ECX
+    # . . call
+    e8/call  has-metadata?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX != 0) return 2
+    3d/compare-EAX-and  0/imm32
+    b8/copy-to-EAX  2/imm32         # ZF is set, so we can overwrite EAX now
+    75/jump-if-not-equal  $compute-width-of-slice:end/disp8
+    # if (has-metadata?(word, "disp16")) return 2
+    # . EAX = has-metadata?(word, "disp16")
+    # . . push args
+    68/push  "disp16"/imm32
+    51/push-ECX
+    # . . call
+    e8/call  has-metadata?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX != 0) return 2
+    3d/compare-EAX-and  0/imm32
+    b8/copy-to-EAX  2/imm32         # ZF is set, so we can overwrite EAX now
+    75/jump-if-not-equal  $compute-width-of-slice:end/disp8
+    # otherwise return 1
+    b8/copy-to-EAX  1/imm32
+$compute-width-of-slice:end:
+    # . restore registers
+    59/pop-to-ECX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-compute-width:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+$test-compute-width:imm8:
+    # EAX = compute-width("0x2/imm8")
+    # . . push args
+    68/push  "0x2/imm8"/imm32
+    # . . call
+    e8/call  compute-width/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-ints-equal(EAX, 1, msg)
+    # . . push args
+    68/push  "F - test-compute-width: 0x2/imm8"/imm32
+    50/push-EAX
+    68/push  1/imm32
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-compute-width:imm16:
+    # EAX = compute-width("4/imm16")
+    # . . push args
+    68/push  "4/imm16"/imm32
+    # . . call
+    e8/call  compute-width/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-ints-equal(EAX, 2, msg)
+    # . . push args
+    68/push  "F - test-compute-width: 4/imm16"/imm32
+    50/push-EAX
+    68/push  2/imm32
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-compute-width:imm32:
+    # EAX = compute-width("4/imm32")
+    # . . push args
+    68/push  "4/imm32"/imm32
+    # . . call
+    e8/call  compute-width/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-ints-equal(EAX, 4, msg)
+    # . . push args
+    68/push  "F - test-compute-width: 4/imm32"/imm32
+    50/push-EAX
+    68/push  4/imm32
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-compute-width:disp8:
+    # EAX = compute-width("foo/disp8")
+    # . . push args
+    68/push  "foo/disp8"/imm32
+    # . . call
+    e8/call  compute-width/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-ints-equal(EAX, 1, msg)
+    # . . push args
+    68/push  "F - test-compute-width: foo/disp8"/imm32
+    50/push-EAX
+    68/push  1/imm32
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-compute-width:disp16:
+    # EAX = compute-width("foo/disp16")
+    # . . push args
+    68/push  "foo/disp16"/imm32
+    # . . call
+    e8/call  compute-width/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-ints-equal(EAX, 2, msg)
+    # . . push args
+    68/push  "F - test-compute-width: foo/disp16"/imm32
+    50/push-EAX
+    68/push  2/imm32
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-compute-width:disp32:
+    # EAX = compute-width("foo/disp32")
+    # . . push args
+    68/push  "foo/disp32"/imm32
+    # . . call
+    e8/call  compute-width/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-ints-equal(EAX, 4, msg)
+    # . . push args
+    68/push  "F - test-compute-width: foo/disp32"/imm32
+    50/push-EAX
+    68/push  4/imm32
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-compute-width:no-metadata:
+    # EAX = compute-width("45")
+    # . . push args
+    68/push  "45"/imm32
+    # . . call
+    e8/call  compute-width/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-ints-equal(EAX, 1, msg)
+    # . . push args
+    68/push  "F - test-compute-width: 45 (no metadata)"/imm32
+    50/push-EAX
+    68/push  1/imm32
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+is-label?: # word : (address slice) -> EAX : boolean
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    51/push-ECX
+    # ECX = word
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           1/r32/ECX   8/disp8         .                 # copy *(EBP+8) to ECX
+    # ECX = word->end
+    8b/copy                         1/mod/*+disp8   1/rm32/ECX    .           .             .           1/r32/ECX   4/disp8         .                 # copy *(ECX+4) to ECX
+    # return *(word->end - 1) == ':'
+    # . EAX = 0
+    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
+    # . EAX = *((char *) word->end - 1)
+    8a/copy-byte                    1/mod/*+disp8   1/rm32/ECX    .           .             .           0/r32/AL    -1/disp8         .                 # copy byte at *(ECX-1) to AL
+    # . return (EAX == ':')
+    3d/compare-EAX-and  0x3a/imm32/colon
+    b8/copy-to-EAX  1/imm32/true
+    74/jump-if-equal  $is-label?:end/disp8
+    b8/copy-to-EAX  0/imm32/false
+$is-label?:end:
+    # . restore registers
+    59/pop-to-ECX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-is-label?:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+$test-is-label?:true:
+    # (EAX..ECX) = "AAA:"
+    b8/copy-to-EAX  "AAA:"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # var slice/ECX = {EAX, ECX}
+    51/push-ECX
+    50/push-EAX
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # is-label?(slice/ECX)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  is-label?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-ints-equal(EAX, 1, msg)
+    # . . push args
+    68/push  "F - test-is-label?:true"/imm32
+    68/push  1/imm32
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$test-is-label?:false:
+    # (EAX..ECX) = "AAA"
+    b8/copy-to-EAX  "AAA"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # var slice/ECX = {EAX, ECX}
+    51/push-ECX
+    50/push-EAX
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # is-label?(slice/ECX)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  is-label?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-ints-equal(EAX, 0, msg)
+    # . . push args
+    68/push  "F - test-is-label?:false"/imm32
+    68/push  0/imm32
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+== data
+
+_test-input-stream:
+    # current write index
+    0/imm32
+    # current read index
+    0/imm32
+    # length
+    0x100/imm32  # 256 bytes
+    # data (16 lines x 16 bytes/line)
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+
+# a test buffered file for _test-input-stream
+_test-input-buffered-file:
+    # file descriptor or (address stream)
+    _test-input-stream/imm32
+    # current write index
+    0/imm32
+    # current read index
+    0/imm32
+    # length
+    6/imm32
+    # data
+    00 00 00 00 00 00  # 6 bytes
+
+_test-output-stream:
+    # current write index
+    0/imm32
+    # current read index
+    0/imm32
+    # length
+    0x200/imm32  # 512 bytes
+    # data (32 lines x 16 bytes/line)
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
+
+# a test buffered file for _test-output-stream
+_test-output-buffered-file:
+    # file descriptor or (address stream)
+    _test-output-stream/imm32
+    # current write index
+    0/imm32
+    # current read index
+    0/imm32
+    # length
+    6/imm32
+    # data
+    00 00 00 00 00 00  # 6 bytes
+
+_test-data-segment:
+  64/d 61/a 74/t 61/a
+_test-data-segment-end:
+
+# . . vim:nowrap:textwidth=0
diff --git a/apps/survey b/apps/survey
new file mode 100755
index 00000000..621efa5c
--- /dev/null
+++ b/apps/survey
Binary files differdiff --git a/apps/survey.subx b/apps/survey.subx
new file mode 100644
index 00000000..15957fa2
--- /dev/null
+++ b/apps/survey.subx
@@ -0,0 +1,4787 @@
+# Assign addresses (co-ordinates) to instructions (landmarks) in a program
+# (landscape).
+# Use the addresses assigned to:
+#   a) replace labels
+#   b) add segment headers with addresses and offsets correctly filled in
+#
+# To build (from the subx/ directory):
+#   $ ./subx translate *.subx apps/survey.subx -o apps/survey
+#
+# The expected input is a stream of bytes with segment headers, comments and
+# some interspersed labels.
+#   $ cat x
+#   == code 0x1
+#   l1:
+#   aa bb l1/imm8
+#   cc dd l2/disp32
+#   l2:
+#   ee foo/imm32
+#   == data 0x10
+#   foo:
+#     00
+#
+# The output is the stream of bytes without segment headers or label definitions,
+# and with label references replaced with numeric values/displacements.
+#
+#   $ cat x  |./subx run apps/assort
+#   ...ELF header bytes...
+#   # ELF header above will specify that code segment begins at this offset
+#   aa bb nn  # some computed address
+#   cc dd nn nn nn nn  # some computed displacement
+#   ee nn nn nn nn  # some computed address
+#   # ELF header above will specify that data segment begins at this offset
+#   00
+#
+# The ELF format has some persnickety constraints on the starting addresses of
+# segments, so input headers are treated as guidelines and adjusted in the
+# output.
+
+== code
+#   instruction                     effective address                                                   register    displacement    immediate
+# . op          subop               mod             rm32          base        index         scale       r32
+# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
+
+Entry:
+    # Heap = new-segment(Heap-size)
+    # . . push args
+    68/push  Heap/imm32
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Heap-size/disp32                  # push *Heap-size
+    # . . call
+    e8/call  new-segment/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # initialize-trace-stream(256KB)
+    # . . push args
+    68/push  0x40000/imm32/256KB
+    # . . call
+    e8/call  initialize-trace-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+
+    # run tests if necessary, convert stdin if not
+    # . prolog
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # initialize heap
+    # - if argc > 1 and argv[1] == "test", then return run_tests()
+    # . argc > 1
+    81          7/subop/compare     1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0/disp8         1/imm32           # compare *EBP
+    7e/jump-if-lesser-or-equal  $run-main/disp8
+    # . argv[1] == "test"
+    # . . push args
+    68/push  "test"/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  kernel-string-equal?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . check result
+    3d/compare-EAX-and  1/imm32
+    75/jump-if-not-equal  $run-main/disp8
+    # . run-tests()
+    e8/call  run-tests/disp32
+    8b/copy                         0/mod/indirect  5/rm32/.disp32            .             .           3/r32/EBX   Num-test-failures/disp32          # copy *Num-test-failures to EBX
+    eb/jump  $main:end/disp8
+$run-main:
+    # - otherwise convert stdin
+    # convert(Stdin, Stdout)
+    # . . push args
+    68/push  Stdout/imm32
+    68/push  Stdin/imm32
+    # . . call
+    e8/call  convert/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, Trace-stream)
+#?     # . . push args
+#?     ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Trace-stream/disp32               # push *Trace-stream
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . syscall(exit, 0)
+    bb/copy-to-EBX  0/imm32
+$main:end:
+    b8/copy-to-EAX  1/imm32/exit
+    cd/syscall  0x80/imm8
+
+# data structures:
+#   segment-info: {address, file-offset, size}            (12 bytes)
+#   segments: (address stream {string, segment-info})     (16 bytes per row)
+#   label-info: {segment-name, segment-offset, address}   (12 bytes)
+#   labels: (address stream {string, label-info})         (16 bytes per row)
+# these are all inefficient; use sequential scans for lookups
+
+convert:  # infile : (address buffered-file), out : (address buffered-file) -> <void>
+    # pseudocode
+    #   var in : (address stream byte) = stream(4096)
+    #   slurp(infile, in)
+    #   var segments = new-stream(10 rows, 16 bytes each)
+    #   var labels = new-stream(Max-labels rows, 16 bytes each)
+    #   compute-offsets(in, segments, labels)
+    #   compute-addresses(segments, labels)
+    #   rewind-stream(in)
+    #   emit-output(in, out, segments, labels)
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    51/push-ECX
+    52/push-EDX
+    56/push-ESI
+    # var segments/ECX = stream(10 * 16)
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xa0/imm32        # subtract from ESP
+    68/push  0xa0/imm32/length
+    68/push  0/imm32/read
+    68/push  0/imm32/write
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # var labels/EDX = stream(Max-labels * 16)
+    # . data
+    2b/subtract                     0/mod/indirect  5/rm32/.disp32            .             .           4/r32/ESP   Max-labels/disp32                 # subtract *Max-labels from ESP
+    # . length
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Max-labels/disp32                 # push *Max-labels
+    # . read
+    68/push  0/imm32/read
+    # . write
+    68/push  0/imm32/write
+    89/copy                         3/mod/direct    2/rm32/EDX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EDX
+    # var in/ESI = stream(Input-size * 1)
+    # . data
+    2b/subtract                     0/mod/indirect  5/rm32/.disp32            .             .           4/r32/ESP   Input-size/disp32                 # subtract *Input-size from ESP
+    # . length
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Input-size/disp32                 # push *Input-size
+    # . read
+    68/push  0/imm32/read
+    # . write
+    68/push  0/imm32/write
+    89/copy                         3/mod/direct    6/rm32/ESI    .           .             .           4/r32/ESP   .               .                 # copy ESP to ESI
+#?     # dump labels->write {{{
+#?     # . write(2/stderr, "labels->write right after initialization: ")
+#?     # . . push args
+#?     68/push  "labels->write right after initialization: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . clear-stream(Stderr+4)
+#?     # . . save EAX
+#?     50/push-EAX
+#?     # . . push args
+#?     b8/copy-to-EAX  Stderr/imm32
+#?     05/add-to-EAX  4/imm32
+#?     50/push-EAX
+#?     # . . call
+#?     e8/call  clear-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . . restore EAX
+#?     58/pop-to-EAX
+#?     # . print-int32-buffered(Stderr, labels->write)
+#?     # . . push args
+#? $watch-1:
+#?     ff          6/subop/push        0/mod/indirect  2/rm32/EDX    .           .             .           .           .               .                 # push *EDX
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  print-int32-buffered/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . flush(Stderr)
+#?     # . . push args
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  flush/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . write(2/stderr, "\n")
+#?     # . . push args
+#?     68/push  "\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+#?     # write(2/stderr, "slurp in\n") {{{
+#?     # . . push args
+#?     68/push  "slurp in\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # slurp(infile, in)
+    # . . push args
+    56/push-ESI
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  slurp/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # dump labels->write {{{
+#?     # . write(2/stderr, "labels->write after slurp: ")
+#?     # . . push args
+#?     68/push  "labels->write after slurp: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . clear-stream(Stderr+4)
+#?     # . . save EAX
+#?     50/push-EAX
+#?     # . . push args
+#?     b8/copy-to-EAX  Stderr/imm32
+#?     05/add-to-EAX  4/imm32
+#?     50/push-EAX
+#?     # . . call
+#?     e8/call  clear-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . . restore EAX
+#?     58/pop-to-EAX
+#?     # . print-int32-buffered(Stderr, labels->write)
+#?     # . . push args
+#?     ff          6/subop/push        0/mod/indirect  2/rm32/EDX    .           .             .           .           .               .                 # push *EDX
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  print-int32-buffered/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . flush(Stderr)
+#?     # . . push args
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  flush/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . write(2/stderr, "\n")
+#?     # . . push args
+#?     68/push  "\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+#?     # dump in {{{
+#?     # . write(2/stderr, "in: ")
+#?     # . . push args
+#?     68/push  "in: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # write-stream(2/stderr, in)
+#?     # . . push args
+#?     56/push-ESI
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . rewind-stream(in)
+#?     # . . push args
+#?     56/push-ESI
+#?     # . . call
+#?     e8/call  rewind-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # }}}
+#?     # write(2/stderr, "compute-offsets\n") {{{
+#?     # . . push args
+#?     68/push  "compute-offsets\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # compute-offsets(in, segments, labels)
+    # . . push args
+    52/push-EDX
+    51/push-ECX
+    56/push-ESI
+    # . . call
+    e8/call  compute-offsets/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+#?     # write(2/stderr, "compute-addresses\n") {{{
+#?     # . . push args
+#?     68/push  "compute-addresses\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # compute-addresses(segments, labels)
+    # . . push args
+    52/push-EDX
+    51/push-ECX
+    # . . call
+    e8/call  compute-addresses/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x8/imm32         # add to ESP
+    # rewind-stream(in)
+    # . . push args
+    56/push-ESI
+    # . . call
+    e8/call  rewind-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # write(2/stderr, "emit-output\n") {{{
+#?     # . . push args
+#?     68/push  "emit-output\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+#?     # dump *Trace-stream {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, *Trace-stream)
+#?     # . . push args
+#?     ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Trace-stream/disp32               # push *Trace-stream
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+#?     # dump labels->write {{{
+#?     # . write(2/stderr, "labels->write after rewinding input: ")
+#?     # . . push args
+#?     68/push  "labels->write after rewinding input: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . clear-stream(Stderr+4)
+#?     # . . save EAX
+#?     50/push-EAX
+#?     # . . push args
+#?     b8/copy-to-EAX  Stderr/imm32
+#?     05/add-to-EAX  4/imm32
+#?     50/push-EAX
+#?     # . . call
+#?     e8/call  clear-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . . restore EAX
+#?     58/pop-to-EAX
+#?     # . print-int32-buffered(Stderr, labels)
+#?     # . . push args
+#?     ff          6/subop/push        0/mod/indirect  2/rm32/EDX    .           .             .           .           .               .                 # push *EDX
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  print-int32-buffered/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . flush(Stderr)
+#?     # . . push args
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  flush/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . write(2/stderr, "\n")
+#?     # . . push args
+#?     68/push  "\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # emit-output(in, out, segments, labels)
+    # . . push args
+    52/push-EDX
+    51/push-ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    56/push-ESI
+    # . . call
+    e8/call  emit-output/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
+    # flush(out)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+$convert:end:
+    # . reclaim locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x30a0/imm32      # add to ESP
+    # . restore registers
+    5e/pop-to-ESI
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-convert-computes-addresses:
+    # input:
+    #   == code 0x1
+    #   Entry:
+    #   ab x/imm32
+    #   == data 0x1000
+    #   x:
+    #     01
+    #
+    # trace contains (in any order):
+    #   label x is at address 0x1079
+    #   segment code starts at address 0x74
+    #   segment code has size 5
+    #   segment data starts at address 0x1079
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-input-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-input-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "== code 0x1\n")
+    # . . push args
+    68/push  "== code 0x1\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "Entry:\n")
+    # . . push args
+    68/push  "Entry:\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "ab x/imm32\n")
+    # . . push args
+    68/push  "ab x/imm32\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "== data 0x1000\n")
+    # . . push args
+    68/push  "== data 0x1000\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "x:\n")
+    # . . push args
+    68/push  "x:\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "01\n")
+    # . . push args
+    68/push  "01\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # convert(_test-input-buffered-file, _test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-buffered-file/imm32
+    # . . call
+    e8/call  convert/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # check trace
+#?     # dump *Trace-stream {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, *Trace-stream)
+#?     # . . push args
+#?     ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Trace-stream/disp32               # push *Trace-stream
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-trace-contains("label 'x' is at address 0x00001079.", msg)
+    # . . push args
+    68/push  "F - test-convert-computes-addresses/0"/imm32
+    68/push  "label 'x' is at address 0x00001079."/imm32
+    # . . call
+    e8/call  check-trace-contains/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . check-trace-contains("segment 'code' starts at address 0x00000074.", msg)
+    # . . push args
+    68/push  "F - test-convert-computes-addresses/1"/imm32
+    68/push  "segment 'code' starts at address 0x00000074."/imm32
+    # . . call
+    e8/call  check-trace-contains/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . check-trace-contains("segment 'code' has size 0x00000005.", msg)
+    # . . push args
+    68/push  "F - test-convert-computes-addresses/2"/imm32
+    68/push  "segment 'code' has size 0x00000005."/imm32
+    # . . call
+    e8/call  check-trace-contains/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . check-trace-contains("segment 'data' starts at address 0x00001079.", msg)
+    # . . push args
+    68/push  "F - test-convert-computes-addresses/3"/imm32
+    68/push  "segment 'data' starts at address 0x00001079."/imm32
+    # . . call
+    e8/call  check-trace-contains/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+# global scratch space for compute-offsets in the data segment
+== data
+
+compute-offsets:file-offset:  # int
+  0/imm32
+compute-offsets:segment-offset:  # int
+  0/imm32
+compute-offsets:word-slice:
+  0/imm32/start
+  0/imm32/end
+compute-offsets:segment-tmp:  # slice
+  0/imm32/start
+  0/imm32/end
+
+== code
+
+compute-offsets:  # in : (address stream), segments : (address stream {string, segment-info}), labels : (address stream {string, label-info})
+    # skeleton:
+    #   for lines in 'in'
+    #     for words in line
+    #       switch word
+    #         case 1
+    #         case 2
+    #         ...
+    #         default
+    #
+    # pseudocode:
+    #   curr-segment-name : (address string) = 0
+    #   var line = new-stream(512, 1)
+    #   while true                                  # line loop
+    #     clear-stream(line)
+    #     read-line(in, line)
+    #     if (line->write == 0) break               # end of file
+    #     while true                                # word loop
+    #       word-slice = next-word(line)
+    #       if slice-empty?(word-slice)             # end of line
+    #         break
+    #       else if slice-starts-with?(word-slice, "#")  # comment
+    #         break                                 # end of line
+    #       else if slice-equal?(word-slice, "==")
+    #         if curr-segment-name != 0
+    #           seg = get-or-insert(segments, curr-segment-name)
+    #           seg->size = *file-offset - seg->file-offset
+    #           trace("segment '", curr-segment-name, "' has size ", seg->size)
+    #         segment-tmp = next-word(line)
+    #         curr-segment-name = slice-to-string(segment-tmp)
+    #         if empty?(curr-segment-name)
+    #           abort
+    #         segment-tmp = next-word(line)
+    #         if slice-empty?(segment-tmp)
+    #           abort
+    #         seg = get-or-insert(segments, curr-segment-name)
+    #         seg->starting-address = parse-hex-int(segment-tmp)
+    #         seg->file-offset = *file-offset
+    #         trace("segment '", curr-segment-name, "' is at file offset ", seg->file-offset)
+    #         segment-offset = 0
+    #         break  (next line)
+    #       else if is-label?(word-slice)
+    #         strip trailing ':' from word-slice
+    #         x : (address label-info) = get-or-insert(labels, name)
+    #         x->segment-name = curr-segment-name
+    #         trace("label '", word-slice, "' is in segment '", curr-segment-name, "'.")
+    #         x->segment-offset = segment-offset
+    #         trace("label '", word-slice, "' is at segment offset ", segment-offset, ".")
+    #         # labels occupy no space, so no need to increment offsets
+    #       else
+    #         width = compute-width-of-slice(word-slice)
+    #         *segment-offset += width
+    #         *file-offset += width
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+    51/push-ECX
+    52/push-EDX
+    53/push-EBX
+    56/push-ESI
+    57/push-EDI
+    # curr-segment-name/ESI = 0
+    31/xor                          3/mod/direct    6/rm32/ESI    .           .             .           6/r32/ESI   .               .                 # clear ESI
+    # file-offset = 0
+    c7          0/subop/copy        0/mod/indirect  5/rm32/.disp32            .             .           .           compute-offsets:file-offset/disp32  0/imm32               # copy to *compute-offsets:word-slice
+    # segment-offset = 0
+    c7          0/subop/copy        0/mod/indirect  5/rm32/.disp32            .             .           .           compute-offsets:segment-offset/disp32  0/imm32            # copy to *compute-offsets:word-slice
+    # line/ECX = new-stream(512, 1)
+    # . EAX = new-stream(512, 1)
+    # . . push args
+    68/push  1/imm32
+    68/push  0x200/imm32
+    68/push  Heap/imm32
+    # . . call
+    e8/call  new-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . line/ECX = EAX
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           0/r32/EAX   .               .                 # copy EAX to ECX
+$compute-offsets:line-loop:
+    # clear-stream(line/ECX)
+    51/push-ECX
+    e8/call  clear-stream/disp32
+    # . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # read-line(in, line/ECX)
+    51/push-ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    e8/call  read-line/disp32
+    # . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # if (line->write == 0) break
+    8b/copy                         0/mod/indirect  1/rm32/ECX    .           .             .           0/r32/EAX   .               .                 # copy *ECX to EAX
+    3d/compare-EAX-and  0/imm32
+    0f 84/jump-if-equal  $compute-offsets:break-line-loop/disp32
+#?     # dump line {{{
+#?     # . write(2/stderr, "LL: ")
+#?     # . . push args
+#?     68/push  "LL: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # write-stream(2/stderr, line)
+#?     # . . push args
+#?     51/push-ECX
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . rewind-stream(line)
+#?     # . . push args
+#?     51/push-ECX
+#?     # . . call
+#?     e8/call  rewind-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # }}}
+$compute-offsets:word-loop:
+    # EDX = word-slice
+    ba/copy-to-EDX  compute-offsets:word-slice/imm32
+    # next-word(line/ECX, word-slice/EDX)
+    52/push-EDX
+    51/push-ECX
+    e8/call  next-word/disp32
+    # . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # dump word-slice and maybe curr-segment-name {{{
+#?     # . write(2/stderr, "w: ")
+#?     # . . push args
+#?     68/push  "w: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . clear-stream(Stderr+4)
+#?     # . . save EAX
+#?     50/push-EAX
+#?     # . . push args
+#?     b8/copy-to-EAX  Stderr/imm32
+#?     05/add-to-EAX  4/imm32
+#?     50/push-EAX
+#?     # . . call
+#?     e8/call  clear-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . . restore EAX
+#?     58/pop-to-EAX
+#?     # . write-slice-buffered(Stderr, word-slice)
+#?     # . . push args
+#?     52/push-EDX
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  write-slice-buffered/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . flush(Stderr)
+#?     # . . push args
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  flush/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . if (curr-segment-name == 0) print curr-segment-name
+#?     81          7/subop/compare     3/mod/direct    6/rm32/ESI    .           .             .           .           .               0/imm32           # compare ESI
+#?     74/jump-if-equal  $compute-offsets:case-empty/disp8
+#?     # . write(2/stderr, "segment at start of word: ")
+#?     # . . push args
+#?     68/push  "segment at start of word: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-buffered(Stderr, curr-segment-name)
+#?     # . . push args
+#?     56/push-ESI
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  write-buffered/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . flush(Stderr)
+#?     # . . push args
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  flush/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+$compute-offsets:case-empty:
+    # if slice-empty?(word/EDX) break
+    # . EAX = slice-empty?(word/EDX)
+    52/push-EDX
+    e8/call  slice-empty?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . if (EAX != 0) break
+    3d/compare-EAX-and  0/imm32
+    0f 85/jump-if-not-equal  $compute-offsets:line-loop/disp32
+$compute-offsets:case-comment:
+    # if slice-starts-with?(word-slice, "#") continue
+    68/push  "#"/imm32
+    52/push-EDX
+    e8/call  slice-starts-with?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX != 0) break
+    3d/compare-EAX-and  0/imm32
+    0f 85/jump-if-not-equal  $compute-offsets:line-loop/disp32
+$compute-offsets:case-segment-header:
+    # if (!slice-equal?(word-slice/EDX, "==")) goto next case
+    # . EAX = slice-equal?(word-slice/EDX, "==")
+    68/push  "=="/imm32
+    52/push-EDX
+    e8/call  slice-equal?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX == 0) goto next case
+    3d/compare-EAX-and  0/imm32
+    0f 84/jump-if-equal  $compute-offsets:case-label/disp32
+    # if (curr-segment-name == 0) goto construct-next-segment
+    81          7/subop/compare     3/mod/direct    6/rm32/ESI    .           .             .           .           .               0/imm32           # compare ESI
+    74/jump-if-equal  $compute-offsets:construct-next-segment/disp8
+    # seg/EAX = get-or-insert(segments, curr-segment-name, row-size=16)
+    # . . push args
+    68/push  0x10/imm32/row-size
+    56/push-ESI
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  get-or-insert/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # seg->size = file-offset - seg->file-offset
+    # . save ECX
+    51/push-ECX
+    # . EBX = *file-offset
+    8b/copy                         0/mod/indirect  5/rm32/.disp32            .             .           3/r32/EBX   compute-offsets:file-offset/disp32 # copy *file-offset to EBX
+    # . ECX = seg->file-offset
+    8b/copy                         1/mod/*+disp8   0/rm32/EAX    .           .             .           1/r32/ECX   4/disp8         .                 # copy *(EAX+4) to ECX
+    # . EBX -= ECX
+    29/subtract                     3/mod/direct    3/rm32/EBX    .           .             .           1/r32/ECX   .               .                 # subtract ECX from EBX
+    # . seg->size = EBX
+    89/copy                         1/mod/*+disp8   0/rm32/EAX    .           .             .           3/r32/EBX   8/disp8         .                 # copy EBX to *(EAX+8)
+    # . restore ECX
+    59/pop-to-ECX
+    # trace-sssns("segment '", curr-segment-name, "' has size ", seg->size, ".")
+    # . . push args
+    68/push  "."/imm32
+    53/push-EBX
+    68/push  "' has size "/imm32
+    56/push-ESI
+    68/push  "segment '"/imm32
+    # . . call
+    e8/call  trace-sssns/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x14/imm32        # add to ESP
+$compute-offsets:construct-next-segment:
+    # next-word(line/ECX, segment-tmp)
+    68/push  compute-offsets:segment-tmp/imm32
+    51/push-ECX
+    e8/call  next-word/disp32
+    # . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # dump curr-segment-name if not null (clobbering EAX) {{{
+#?     # . if (curr-segment-name == 0) goto update-curr-segment-name
+#?     81          7/subop/compare     3/mod/direct    6/rm32/ESI    .           .             .           .           .               0/imm32           # compare ESI
+#?     74/jump-if-equal  $compute-offsets:update-curr-segment-name/disp8
+#?     # . write(2/stderr, "setting segment to: ")
+#?     # . . push args
+#?     68/push  "setting segment to: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . clear-stream(Stderr+4)
+#?     # . . push args
+#?     b8/copy-to-EAX  Stderr/imm32
+#?     05/add-to-EAX  4/imm32
+#?     50/push-EAX
+#?     # . . call
+#?     e8/call  clear-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . . restore EAX
+#?     58/pop-to-EAX
+#?     # . write-buffered(Stderr, curr-segment-name)
+#?     # . . push args
+#?     56/push-ESI
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  write-buffered/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . flush(Stderr)
+#?     # . . push args
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  flush/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+$compute-offsets:update-curr-segment-name:
+    # curr-segment-name = slice-to-string(segment-tmp)
+    # . EAX = slice-to-string(Heap, segment-tmp)
+    # . . push args
+    68/push  compute-offsets:segment-tmp/imm32
+    68/push  Heap/imm32
+    # . . call
+    e8/call  slice-to-string/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . curr-segment-name = EAX
+    89/copy                         3/mod/direct    6/rm32/ESI    .           .             .           0/r32/EAX   .               .                 # copy EAX to ESI
+    # if empty?(curr-segment-name) abort
+    # . if (EAX == 0) abort
+    3d/compare-EAX-and  0/imm32
+    0f 84/jump-if-equal  $compute-offsets:abort/disp32
+    # next-word(line/ECX, segment-tmp)
+    68/push  compute-offsets:segment-tmp/imm32
+    51/push-ECX
+    e8/call  next-word/disp32
+    # . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # if slice-empty?(segment-tmp) abort
+    # . EAX = slice-empty?(segment-tmp)
+    68/push  compute-offsets:segment-tmp/imm32
+    e8/call  slice-empty?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . if (EAX != 0) abort
+    3d/compare-EAX-and  0/imm32
+    0f 85/jump-if-not-equal  $compute-offsets:abort/disp32
+    # seg/EBX = get-or-insert(segments, curr-segment-name, row-size=16)
+    # . . push args
+    68/push  0x10/imm32/row-size
+    56/push-ESI
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  get-or-insert/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . EBX = EAX
+    89/copy                         3/mod/direct    3/rm32/EBX    .           .             .           0/r32/EAX   .               .                 # copy EAX to EBX
+    # seg->address = parse-hex-int(segment-tmp)
+    # . EAX = parse-hex-int(segment-tmp)
+    68/push  compute-offsets:segment-tmp/imm32
+    e8/call  parse-hex-int/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . seg->address = EAX
+    89/copy                         0/mod/indirect  3/rm32/EBX    .           .             .           0/r32/EAX   .               .                 # copy EAX to *EBX
+    # seg->file-offset = *file-offset
+    8b/copy                         0/mod/indirect  5/rm32/.disp32            .             .           0/r32/EAX   compute-offsets:file-offset/disp32 # copy *file-offset to EAX
+    89/copy                         1/mod/*+disp8   3/rm32/EBX    .           .             .           0/r32/EAX   4/disp8         .                 # copy EAX to *(EBX+4)
+    # trace-sssns("segment '", curr-segment-name, "' is at file offset ", seg->file-offset, "")
+    # . . push args
+    68/push  "."/imm32
+    50/push-EAX
+    68/push  "' is at file offset "/imm32
+    56/push-ESI
+    68/push  "segment '"/imm32
+    # . . call
+    e8/call  trace-sssns/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x14/imm32        # add to ESP
+    # segment-offset = 0
+    c7          0/subop/copy        0/mod/indirect  5/rm32/.disp32            .             .           .     compute-offsets:segment-offset/disp32  0/imm32           # copy to *segment-offset
+    # break
+    e9/jump $compute-offsets:line-loop/disp32
+$compute-offsets:case-label:
+    # if (!is-label?(word-slice/EDX)) goto next case
+    # . EAX = is-label?(word-slice/EDX)
+    # . . push args
+    52/push-EDX
+    # . . call
+    e8/call  is-label?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . if (EAX == 0) goto next case
+    3d/compare-EAX-and  0/imm32
+    74/jump-if-equal  $compute-offsets:case-default/disp8
+    # strip trailing ':' from word-slice
+    ff          1/subop/decrement   1/mod/*+disp8   2/rm32/EDX    .           .             .           .           4/disp8         .                 # decrement *(EDX+4)
+    # x/EAX = leaky-get-or-insert-slice(labels, word-slice, row-size=16)
+    # . . push args
+    68/push  0x10/imm32/row-size
+    52/push-EDX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x10/disp8      .                 # push *(EBP+16)
+    # . . call
+    e8/call  leaky-get-or-insert-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+$compute-offsets:save-label-offset:
+    # x->segment-name = curr-segment-name
+    89/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           6/r32/ESI   .               .                 # copy ESI to *EAX
+    # trace-slsss("label '" word-slice/EDX "' is in segment '" current-segment-name "'.")
+    # . . push args
+    68/push  "'."/imm32
+    56/push-ESI
+    68/push  "' is in segment '"/imm32
+    52/push-EDX
+    68/push  "label '"/imm32
+    # . . call
+    e8/call  trace-slsss/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x14/imm32        # add to ESP
+    # x->segment-offset = segment-offset
+    # . EBX = segment-offset
+    8b/copy                         0/mod/indirect  5/rm32/.disp32            .             .           3/r32/EBX   compute-offsets:segment-offset/disp32  # copy *segment-offset to EBX
+    # . x->segment-offset = EBX
+    89/copy                         1/mod/*+disp8   0/rm32/EAX    .           .             .           3/r32/EBX   4/disp8         .                 # copy EBX to *(EAX+4)
+    # trace-slsns("label '" word-slice/EDX "' is at segment offset " *segment-offset/EAX ".")
+    # . . EAX = file-offset
+    b8/copy-to-EAX compute-offsets:segment-offset/imm32
+    # . . EAX = *file-offset/EAX
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # copy *EAX to EAX
+    # . . push args
+    68/push  "."/imm32
+    50/push-EAX
+    68/push  "' is at segment offset "/imm32
+    52/push-EDX
+    68/push  "label '"/imm32
+    # . . call
+    e8/call  trace-slsns/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x14/imm32        # add to ESP
+    # continue
+    e9/jump  $compute-offsets:word-loop/disp32
+$compute-offsets:case-default:
+    # width/EAX = compute-width-of-slice(word-slice)
+    # . . push args
+    52/push-EDX
+    # . . call
+    e8/call compute-width-of-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # segment-offset += width
+    01/add                          0/mod/indirect  5/rm32/.disp32            .             .           0/r32/EAX   compute-offsets:segment-offset/disp32 # add EAX to *segment-offset
+    # file-offset += width
+    01/add                          0/mod/indirect  5/rm32/.disp32            .             .           0/r32/EAX   compute-offsets:file-offset/disp32 # add EAX to *file-offset
+#?     # dump segment-offset {{{
+#?     # . write(2/stderr, "segment-offset: ")
+#?     # . . push args
+#?     68/push  "segment-offset: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . clear-stream(Stderr+4)
+#?     # . . save EAX
+#?     50/push-EAX
+#?     # . . push args
+#?     b8/copy-to-EAX  Stderr/imm32
+#?     05/add-to-EAX  4/imm32
+#?     50/push-EAX
+#?     # . . call
+#?     e8/call  clear-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . . restore EAX
+#?     58/pop-to-EAX
+#?     # . print-int32-buffered(Stderr, segment-offset)
+#?     # . . push args
+#?     52/push-EDX
+#?     ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           compute-offsets:segment-offset/disp32  # push *segment-offset
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  print-int32-buffered/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . flush(Stderr)
+#?     # . . push args
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  flush/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . write(2/stderr, "\n")
+#?     # . . push args
+#?     68/push  "\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    e9/jump $compute-offsets:word-loop/disp32
+$compute-offsets:break-line-loop:
+    # seg/EAX = get-or-insert(segments, curr-segment-name, row-size=16)
+    # . . push args
+    68/push  0x10/imm32/row-size
+    56/push-ESI
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  get-or-insert/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # seg->size = file-offset - seg->file-offset
+    # . save ECX
+    51/push-ECX
+    # . EBX = *file-offset
+    8b/copy                         0/mod/indirect  5/rm32/.disp32            .             .           3/r32/EBX   compute-offsets:file-offset/disp32 # copy *file-offset to EBX
+    # . ECX = seg->file-offset
+    8b/copy                         1/mod/*+disp8   0/rm32/EAX    .           .             .           1/r32/ECX   4/disp8         .                 # copy *(EAX+4) to ECX
+    # . EBX -= ECX
+    29/subtract                     3/mod/direct    3/rm32/EBX    .           .             .           1/r32/ECX   .               .                 # subtract ECX from EBX
+    # . seg->size = EBX
+    89/copy                         1/mod/*+disp8   0/rm32/EAX    .           .             .           3/r32/EBX   8/disp8         .                 # copy EBX to *(EAX+8)
+    # . restore ECX
+    59/pop-to-ECX
+    # trace-sssns("segment '", curr-segment-name, "' has size ", seg->size, ".")
+    # . trace-sssns("segment '", curr-segment-name, "' has size ", EBX, ".")
+    # . . push args
+    68/push  "."/imm32
+    53/push-EBX
+    68/push  "' has size "/imm32
+    56/push-ESI
+    68/push  "segment '"/imm32
+    # . . call
+    e8/call  trace-sssns/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x14/imm32        # add to ESP
+$compute-offsets:end:
+    # . reclaim locals
+    # . restore registers
+    5f/pop-to-EDI
+    5e/pop-to-ESI
+    5b/pop-to-EBX
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+$compute-offsets:abort:
+    # . _write(2/stderr, error)
+    # . . push args
+    68/push  "'==' must be followed by segment name and segment-start\n"/imm32
+    68/push  2/imm32/stderr
+    # . . call
+    e8/call  _write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . syscall(exit, 1)
+    bb/copy-to-EBX  1/imm32
+    b8/copy-to-EAX  1/imm32/exit
+    cd/syscall  0x80/imm8
+    # never gets here
+
+test-compute-offsets:
+    # input:
+    #   == code 0x1
+    #   ab x/imm32  # skip comment
+    #   == data 0x1000
+    #   00
+    #   x:
+    #     34
+    #
+    # trace contains (in any order):
+    #   segment 'code' is at file offset 0x0.
+    #   segment 'code' has size 0x5.
+    #   segment 'data' is at file offset 0x5.
+    #   segment 'data' has size 0x2.
+    #   label 'x' is in segment 'data'.
+    #   label 'x' is at segment offset 0x1.
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # var segments/ECX = stream(2 * 16)
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x20/imm32        # subtract from ESP
+    68/push  0x20/imm32/length
+    68/push  0/imm32/read
+    68/push  0/imm32/write
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # var labels/EDX = stream(2 * 16)
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x20/imm32        # subtract from ESP
+    68/push  0x20/imm32/length
+    68/push  0/imm32/read
+    68/push  0/imm32/write
+    89/copy                         3/mod/direct    2/rm32/EDX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EDX
+    # initialize input
+    # . write(_test-input-stream, "== code 0x1\n")
+    # . . push args
+    68/push  "== code 0x1\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "ab x/imm32  # skip comment\n")
+    # . . push args
+    68/push  "ab x/imm32  # skip comment\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "== data 0x1000\n")
+    # . . push args
+    68/push  "== data 0x1000\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "00\n")
+    # . . push args
+    68/push  "00\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "x:\n")
+    # . . push args
+    68/push  "x:\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "34\n")
+    # . . push args
+    68/push  "34\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # compute-offsets(_test-input-stream, segments, labels)
+    # . . push args
+    52/push-EDX
+    51/push-ECX
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  compute-offsets/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32        # add to ESP
+#?     # dump *Trace-stream {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, *Trace-stream)
+#?     # . . push args
+#?     ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Trace-stream/disp32               # push *Trace-stream
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # check trace
+    # . check-trace-contains("segment 'code' is at file offset 0x00000000.", msg)
+    # . . push args
+    68/push  "F - test-compute-offsets/0"/imm32
+    68/push  "segment 'code' is at file offset 0x00000000."/imm32
+    # . . call
+    e8/call  check-trace-contains/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . check-trace-contains("segment 'code' has size 0x00000005", msg)
+    # . . push args
+    68/push  "F - test-compute-offsets/1"/imm32
+    68/push  "segment 'code' has size 0x00000005."/imm32
+    # . . call
+    e8/call  check-trace-contains/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . check-trace-contains("segment 'data' is at file offset 0x00000005.", msg)
+    # . . push args
+    68/push  "F - test-compute-offsets/2"/imm32
+    68/push  "segment 'data' is at file offset 0x00000005."/imm32
+    # . . call
+    e8/call  check-trace-contains/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . check-trace-contains("segment 'data' has size 0x00000002.", msg)
+    # . . push args
+    68/push  "F - test-compute-offsets/3"/imm32
+    68/push  "segment 'data' has size 0x00000002."/imm32
+    # . . call
+    e8/call  check-trace-contains/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . check-trace-contains("label 'x' is in segment 'data'.", msg)
+    # . . push args
+    68/push  "F - test-compute-offsets/4"/imm32
+    68/push  "label 'x' is in segment 'data'."/imm32
+    # . . call
+    e8/call  check-trace-contains/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . check-trace-contains("label 'x' is at segment offset 0x00000001.", msg)
+    # . . push args
+    68/push  "F - test-compute-offsets/5"/imm32
+    68/push  "label 'x' is at segment offset 0x00000001."/imm32
+    # . . call
+    e8/call  check-trace-contains/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . check-ints-equal(labels->write, 0x10, msg)
+    # . . push args
+    68/push  "F - test-compute-offsets-maintains-labels-write-index"/imm32
+    68/push  0x10/imm32/1-entry
+    ff          6/subop/push        0/mod/indirect  2/rm32/EDX    .           .             .           .           .               .                 # push *EDX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+compute-addresses:  # segments : (address stream {string, segment-info}), labels : (address stream {string, label-info})
+    # pseudocode:
+    #   srow : (address segment-info) = segments->data
+    #   max = segments->data + segments->write
+    #   num-segments = segments->write / 16
+    #   starting-offset = 0x34 + (num-segments * 0x20)
+    #   while true
+    #     if (srow >= max) break
+    #     s->file-offset += starting-offset
+    #     s->address &= 0xfffff000  # clear last 12 bits for p_align
+    #     s->address += (s->file-offset & 0x00000fff)
+    #     trace-sssns("segment " s->key " starts at address " s->address)
+    #     srow += 16  # row-size
+    #   lrow : (address label-info) = labels->data
+    #   max = labels->data + labels->write
+    #   while true
+    #     if (lrow >= max) break
+    #     seg-name : (address string) = lrow->segment-name
+    #     label-seg : (address segment-info) = get(segments, seg-name, row-size=16)
+    #     lrow->address = label-seg->address + lrow->segment-offset
+    #     trace-sssns("label " lrow->key " is at address " lrow->address)
+    #     lrow += 16  # row-size
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+    51/push-ECX
+    52/push-EDX
+    53/push-EBX
+    56/push-ESI
+    57/push-EDI
+    # ESI = segments
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   8/disp8         .                 # copy *(EBP+8) to ESI
+    # starting-offset/EDI = 0x34 + (num-segments * 0x20)  # make room for ELF headers
+    # . EDI = segments->write / 16 (row-size)
+    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           7/r32/EDI   .               .                 # copy *ESI to EDI
+    c1/shift    5/subop/logic-right 3/mod/direct    7/rm32/EDI    .           .             .           .           .               4/imm8            # shift EDI right by 4 bits, while padding zeroes
+    # . EDI = (EDI * 0x20) + 0x34
+    c1/shift    4/subop/left        3/mod/direct    7/rm32/EDI    .           .             .           .           .               5/imm8            # shift EDI left by 5 bits
+    81          0/subop/add         3/mod/direct    7/rm32/EDI    .           .             .           .           .               0x34/imm32        # add to EDI
+    # srow/EAX = segments->data
+    8d/copy-address                 1/mod/*+disp8   6/rm32/ESI    .           .             .           0/r32/EAX   0xc/disp8       .                 # copy ESI+12 to EAX
+    # max/ECX = segments->data + segments->write
+    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           1/r32/ECX   .               .                 # copy *ESI to ECX
+    01/add                          3/mod/direct    1/rm32/ECX    .           .             .           6/r32/ESI   .               .                 # add ESI to ECX
+$compute-addresses:segment-loop:
+    # if (srow >= max) break
+    39/compare                      3/mod/direct    0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # compare EAX with ECX
+    73/jump-if-greater-or-equal-unsigned  $compute-addresses:segment-break/disp8
+    # srow->file-offset += starting-offset
+    01/add                          1/mod/*+disp8   0/rm32/EAX    .           .             .           7/r32/EDI   8/disp8         .                 # add EDI to *(EAX+8)
+    # clear last 12 bits of srow->address for p_align=0x1000
+    # . EDX = srow->address
+    8b/copy                         1/mod/*+disp8   0/rm32/EAX    .           .             .           2/r32/EDX   4/disp8         .                 # copy *(EAX+4) to EDX
+    # . EDX &= 0xfffff000
+    81          4/subop/and         3/mod/direct    2/rm32/EDX    .           .             .           .           .               0xfffff000/imm32  # bitwise and of EDX
+    # update last 12 bits from srow->file-offset
+    # . EBX = srow->file-offset
+    8b/copy                         1/mod/*+disp8   0/rm32/EAX    .           .             .           3/r32/EBX   8/disp8         .                 # copy *(EAX+8) to EBX
+    # . EBX &= 0xfff
+    81          4/subop/and         3/mod/direct    3/rm32/EBX    .           .             .           .           .               0x00000fff/imm32  # bitwise and of EBX
+    # . srow->address = EDX | EBX
+    09/or                           3/mod/direct    2/rm32/EDX    .           .             .           3/r32/EBX   .               .                 # EDX = bitwise OR with EBX
+    89/copy                         1/mod/*+disp8   0/rm32/EAX    .           .             .           2/r32/EDX   4/disp8         .                 # copy EDX to *(EAX+4)
+    # trace-sssns("segment " srow " starts at address " srow->address ".")
+    # . . push args
+    68/push  "."/imm32
+    52/push-EDX
+    68/push  "' starts at address "/imm32
+    ff          6/subop/push        0/mod/indirect  0/rm32/EAX    .           .             .           .           .               .                 # push *EAX
+    68/push  "segment '"/imm32
+    # . . call
+    e8/call  trace-sssns/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x14/imm32        # add to ESP
+    # srow += 16  # size of row
+    05/add-to-EAX  0x10/imm32
+    eb/jump  $compute-addresses:segment-loop/disp8
+$compute-addresses:segment-break:
+#?     # dump *Trace-stream {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, *Trace-stream)
+#?     # . . push args
+#?     ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Trace-stream/disp32               # push *Trace-stream
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # ESI = labels
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   0xc/disp8       .                 # copy *(EBP+12) to ESI
+    # lrow/EAX = labels->data
+    8d/copy-address                 1/mod/*+disp8   6/rm32/ESI    .           .             .           0/r32/EAX   0xc/disp8       .                 # copy ESI+12 to EAX
+    # max/ECX = labels->data + labels->write
+    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           1/r32/ECX   .               .                 # copy *ESI to ECX
+    01/add                          3/mod/direct    1/rm32/ECX    .           .             .           6/r32/ESI   .               .                 # add ESI to ECX
+$compute-addresses:label-loop:
+    # if (lrow >= max) break
+    39/compare                      3/mod/direct    0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # compare EAX with ECX
+    0f 83/jump-if-greater-or-equal-unsigned  $compute-addresses:end/disp32
+#?     # dump lrow->key {{{
+#?     # . write(2/stderr, "label: ")
+#?     # . . push args
+#?     68/push  "label: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, lrow->key)
+#?     # . . push args
+#?     ff          6/subop/push        0/mod/indirect  0/rm32/EAX    .           .             .           .           .               .                 # push *EAX
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # seg-name/EDX = lrow->segment-name
+    8b/copy                         1/mod/*+disp8   0/rm32/EAX    .           .             .           2/r32/EDX   4/disp8         .                 # copy *EAX to EDX
+#?     # dump seg-name {{{
+#?     # . write(2/stderr, "compute-addresses: seg-name: ")
+#?     # . . push args
+#?     68/push  "seg-name: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, seg-name)
+#?     # . . push args
+#?     52/push-EDX
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # label-seg/EDX : (address segment-info) = get(segments, seg-name, row-size=16)
+    # . save EAX
+    50/push-EAX
+    # . EAX = get(segments, seg-name, row-size=16)
+    # . . push args
+    68/push  0x10/imm32/row-size
+    52/push-EDX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  get/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . EDX = EAX
+    89/copy                         3/mod/direct    2/rm32/EDX    .           .             .           0/r32/EAX   .               .                 # copy EAX to EDX
+    # . restore EAX
+    58/pop-to-EAX
+    # EBX = label-seg->address
+    8b/copy                         0/mod/indirect  2/rm32/EDX    .           .             .           3/r32/EBX   .               .                 # copy *EDX to EBX
+    # EBX += lrow->segment-offset
+    03/add                          1/mod/*+disp8   0/rm32/EAX    .           .             .           3/r32/EBX   8/disp8         .                 # add *(EAX+8) to EBX
+    # lrow->address = EBX
+    89/copy                         1/mod/*+disp8   0/rm32/EAX    .           .             .           3/r32/EBX   0xc/disp8       .                 # copy EBX to *(EAX+12)
+    # trace-sssns("label " lrow->key " is at address " lrow->address ".")
+    # . . push args
+    68/push  "."/imm32
+    53/push-EBX
+    68/push  "' is at address "/imm32
+    ff          6/subop/push        0/mod/indirect  0/rm32/EAX    .           .             .           .           .               .                 # push *EAX
+    68/push  "label '"/imm32
+    # . . call
+    e8/call  trace-sssns/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x14/imm32        # add to ESP
+    # lrow += 16  # size of row
+    05/add-to-EAX  0x10/imm32
+    e9/jump  $compute-addresses:label-loop/disp32
+$compute-addresses:end:
+    # . restore registers
+    5f/pop-to-EDI
+    5e/pop-to-ESI
+    5b/pop-to-EBX
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-compute-addresses:
+    # input:
+    #   segments:
+    #     - 'a': {0x1000, 0, 5}
+    #     - 'b': {0x2018, 5, 1}
+    #     - 'c': {0x5444, 6, 12}
+    #   labels:
+    #     - 'l1': {'a', 3, 0}
+    #     - 'l2': {'b', 0, 0}
+    #
+    # trace contains in any order (comments in parens):
+    #   segment 'a' starts at address 0x00001094.  (0x34 + 0x20 for each segment)
+    #   segment 'b' starts at address 0x00002099.  (0x018 discarded)
+    #   segment 'c' starts at address 0x0000509a.  (0x444 discarded)
+    #   label 'l1' is at address 0x00001097.       (0x1094 + segment-offset 3)
+    #   label 'l2' is at address 0x00002099.       (0x2099 + segment-offset 0)
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . var segments/ECX = stream(10 * 16)
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xa0/imm32        # subtract from ESP
+    68/push  0xa0/imm32/length
+    68/push  0/imm32/read
+    68/push  0/imm32/write
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # . var labels/EDX = stream(512 * 16)
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x2000/imm32      # subtract from ESP
+    68/push  0x2000/imm32/length
+    68/push  0/imm32/read
+    68/push  0/imm32/write
+    89/copy                         3/mod/direct    2/rm32/EDX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EDX
+    # . stream-add4(segments, "a", 0x1000, 0, 5)
+    68/push  5/imm32/segment-size
+    68/push  0/imm32/file-offset
+    68/push  0x1000/imm32/start-address
+    68/push  "a"/imm32/segment-name
+    51/push-ECX
+    # . . call
+    e8/call  stream-add4/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x14/imm32        # add to ESP
+    # . stream-add4(segments, "b", 0x2018, 5, 1)
+    68/push  1/imm32/segment-size
+    68/push  5/imm32/file-offset
+    68/push  0x2018/imm32/start-address
+    68/push  "b"/imm32/segment-name
+    51/push-ECX
+    # . . call
+    e8/call  stream-add4/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x14/imm32        # add to ESP
+    # . stream-add4(segments, "c", 0x5444, 6, 12)
+    68/push  0xc/imm32/segment-size
+    68/push  6/imm32/file-offset
+    68/push  0x5444/imm32/start-address
+    68/push  "c"/imm32/segment-name
+    51/push-ECX
+    # . . call
+    e8/call  stream-add4/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x14/imm32        # add to ESP
+    # . stream-add4(labels, "l1", "a", 3, 0)
+    68/push  0/imm32/label-address
+    68/push  3/imm32/segment-offset
+    68/push  "a"/imm32/segment-name
+    68/push  "l1"/imm32/label-name
+    52/push-EDX
+    # . . call
+    e8/call  stream-add4/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x14/imm32        # add to ESP
+    # . stream-add4(labels, "l2", "b", 0, 0)
+    68/push  0/imm32/label-address
+    68/push  0/imm32/segment-offset
+    68/push  "b"/imm32/segment-name
+    68/push  "l2"/imm32/label-name
+    52/push-EDX
+    # . . call
+    e8/call  stream-add4/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x14/imm32        # add to ESP
+    # component under test
+    # . compute-addresses(segments, labels)
+    # . . push args
+    52/push-EDX
+    51/push-ECX
+    # . . call
+    e8/call  compute-addresses/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # checks
+#?     # dump *Trace-stream {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, *Trace-stream)
+#?     # . . push args
+#?     ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Trace-stream/disp32               # push *Trace-stream
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . check-trace-contains("segment 'a' starts at address 0x00001094.", msg)
+    # . . push args
+    68/push  "F - test-compute-addresses/0"/imm32
+    68/push  "segment 'a' starts at address 0x00001094."/imm32
+    # . . call
+    e8/call  check-trace-contains/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . check-trace-contains("segment 'b' starts at address 0x00002099.", msg)
+    # . . push args
+    68/push  "F - test-compute-addresses/1"/imm32
+    68/push  "segment 'b' starts at address 0x00002099."/imm32
+    # . . call
+    e8/call  check-trace-contains/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . check-trace-contains("segment 'c' starts at address 0x0000509a.", msg)
+    # . . push args
+    68/push  "F - test-compute-addresses/2"/imm32
+    68/push  "segment 'c' starts at address 0x0000509a."/imm32
+    # . . call
+    e8/call  check-trace-contains/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . check-trace-contains("label 'l1' is at address 0x00001097.", msg)
+    # . . push args
+    68/push  "F - test-compute-addresses/3"/imm32
+    68/push  "label 'l1' is at address 0x00001097."/imm32
+    # . . call
+    e8/call  check-trace-contains/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . check-trace-contains("label 'l2' is at address 0x00002099.", msg)
+    # . . push args
+    68/push  "F - test-compute-addresses/4"/imm32
+    68/push  "label 'l2' is at address 0x00002099."/imm32
+    # . . call
+    e8/call  check-trace-contains/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . check-ints-equal(labels->write, 0x20, msg)
+    # . . push args
+    68/push  "F - test-compute-addresses/maintains-labels-write-index"/imm32
+    68/push  0x20/imm32/2-entries
+    ff          6/subop/push        0/mod/indirect  2/rm32/EDX    .           .             .           .           .               .                 # push *EDX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-compute-addresses-large-segments:
+    # input:
+    #   segments:
+    #     - 'a': {0x1000, 0, 0x5604}
+    #     - 'b': {0x2018, 0x5604, 1}
+    #   labels:
+    #     - 'l1': {'a', 3, 0}
+    #
+    # trace contains in any order (comments in parens):
+    #   segment 'a' starts at address 0x00001074.  (0x34 + 0x20 for each segment)
+    #   segment 'b' starts at address 0x00002678.  (0x018 discarded; last 3 nibbles from 0x1074 + 0x5604)
+    #   label 'l1' is at address 0x00001077.       (0x1074 + segment-offset 3)
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . var segments/ECX = stream(10 * 16)
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xa0/imm32        # subtract from ESP
+    68/push  0xa0/imm32/length
+    68/push  0/imm32/read
+    68/push  0/imm32/write
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # . var labels/EDX = stream(512 * 16)
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x2000/imm32      # subtract from ESP
+    68/push  0x2000/imm32/length
+    68/push  0/imm32/read
+    68/push  0/imm32/write
+    89/copy                         3/mod/direct    2/rm32/EDX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EDX
+    # . stream-add4(segments, "a", 0x1000, 0, 0x5604)
+    68/push  0x5604/imm32/segment-size
+    68/push  0/imm32/file-offset
+    68/push  0x1000/imm32/start-address
+    68/push  "a"/imm32/segment-name
+    51/push-ECX
+    # . . call
+    e8/call  stream-add4/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x14/imm32        # add to ESP
+    # . stream-add4(segments, "b", 0x2018, 0x5604, 1)
+    68/push  1/imm32/segment-size
+    68/push  0x5604/imm32/file-offset
+    68/push  0x2018/imm32/start-address
+    68/push  "b"/imm32/segment-name
+    51/push-ECX
+    # . . call
+    e8/call  stream-add4/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x14/imm32        # add to ESP
+    # . stream-add4(labels, "l1", "a", 3, 0)
+    68/push  0/imm32/label-address
+    68/push  3/imm32/segment-offset
+    68/push  "a"/imm32/segment-name
+    68/push  "l1"/imm32/label-name
+    52/push-EDX
+    # . . call
+    e8/call  stream-add4/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x14/imm32        # add to ESP
+    # component under test
+    # . compute-addresses(segments, labels)
+    # . . push args
+    52/push-EDX
+    51/push-ECX
+    # . . call
+    e8/call  compute-addresses/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # checks
+    # . check-trace-contains("segment 'a' starts at address 0x00001074.", msg)
+    # . . push args
+    68/push  "F - test-compute-addresses-large-segments/0"/imm32
+    68/push  "segment 'a' starts at address 0x00001074."/imm32
+    # . . call
+    e8/call  check-trace-contains/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . check-trace-contains("segment 'b' starts at address 0x00002678.", msg)
+    # . . push args
+    68/push  "F - test-compute-addresses-large-segments/1"/imm32
+    68/push  "segment 'b' starts at address 0x00002678."/imm32
+    # . . call
+    e8/call  check-trace-contains/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . check-trace-contains("label 'l1' is at address 0x00001077.", msg)
+    # . . push args
+    68/push  "F - test-compute-addresses-large-segments/3"/imm32
+    68/push  "label 'l1' is at address 0x00001077."/imm32
+    # . . call
+    e8/call  check-trace-contains/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+emit-output:  # in : (address stream), out : (address buffered-file), segments : (address stream {string, segment-info}), labels : (address stream {string, label-info})
+    # pseudocode:
+    #   emit-headers(out, segments, labels)
+    #   emit-segments(in, out, segments, labels)
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+#?     # write(2/stderr, "emit-headers\n") {{{
+#?     # . . push args
+#?     68/push  "emit-headers\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # emit-headers(out, segments, labels)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x14/disp8       .                # push *(EBP+20)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x10/disp8       .                # push *(EBP+16)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8        .                # push *(EBP+12)
+    # . . call
+    e8/call  emit-headers/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+#?     # write(2/stderr, "emit-segments\n") {{{
+#?     # . . push args
+#?     68/push  "emit-segments\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # emit-segments(in, out, segments, labels)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x14/disp8       .                # push *(EBP+20)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x10/disp8       .                # push *(EBP+16)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  emit-segments/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
+$emit-output:end:
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+emit-segments:  # in : (address stream), out : (address buffered-file), segments : (address stream {string, segment-info}), labels : (address stream {string, label-info})
+    # pseudocode:
+    #   var offset-of-next-instruction = 0
+    #   var line = new-stream(512, 1)
+    #   line-loop:
+    #   while true
+    #     clear-stream(line)
+    #     read-line(in, line)
+    #     if (line->write == 0) break               # end of file
+    #     offset-of-next-instruction += num-bytes(line)
+    #     while true
+    #       var word-slice = next-word(line)
+    #       if slice-empty?(word-slice)             # end of line
+    #         break
+    #       if slice-starts-with?(word-slice, "#")  # comment
+    #         break
+    #       if is-label?(word-slice)                # no need for label declarations anymore
+    #         goto line-loop                        # don't insert empty lines
+    #       if slice-equal?(word-slice, "==")       # no need for segment header lines
+    #         goto line-loop                        # don't insert empty lines
+    #       if length(word-slice) == 2
+    #         write-slice-buffered(out, word-slice)
+    #         write-buffered(out, " ")
+    #         continue
+    #       datum = next-token-from-slice(word-slice->start, word-slice->end, "/")
+    #       info = get-slice(labels, datum)
+    #       if !string-equal?(info->segment-name, "code")
+    #         if has-metadata?(word-slice, "disp8")
+    #           abort
+    #         if has-metadata?(word-slice, "imm8")
+    #           abort
+    #         emit(out, info->address, 4)  # global variables always translate to absolute addresses
+    #       # code segment cases
+    #       else if has-metadata?(word-slice, "imm8")
+    #         abort  # label should never go to imm8
+    #       else if has-metadata?(word-slice, "imm32")
+    #         emit(out, info->address, 4)
+    #       else if has-metadata?(word-slice, "disp8")
+    #         value = info->offset - offset-of-next-instruction
+    #         emit(out, value, 1)
+    #       else if has-metadata?(word-slice, "disp32")
+    #         value = info->offset - offset-of-next-instruction
+    #         emit(out, value, 4)
+    #       else
+    #         abort
+    #     write-buffered(out, "\n")
+    #
+    # registers:
+    #   line: ECX
+    #   word-slice: EDX
+    #   offset-of-next-instruction: EBX
+    #   datum: EDI
+    #   info: ESI (inner loop only)
+    #   temporaries: EAX, ESI (outer loop)
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+    51/push-ECX
+    52/push-EDX
+    53/push-EBX
+    56/push-ESI
+    57/push-EDI
+    # var line/ECX : (address stream byte) = stream(512)
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x200/imm32       # subtract from ESP
+    68/push  0x200/imm32/length
+    68/push  0/imm32/read
+    68/push  0/imm32/write
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # var word-slice/EDX = {0, 0}
+    68/push  0/imm32/end
+    68/push  0/imm32/start
+    89/copy                         3/mod/direct    2/rm32/EDX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EDX
+    # var datum/EDI = {0, 0}
+    68/push  0/imm32/end
+    68/push  0/imm32/start
+    89/copy                         3/mod/direct    7/rm32/EDI    .           .             .           4/r32/ESP   .               .                 # copy ESP to EDI
+    # offset-of-next-instruction/EBX = 0
+    31/xor                          3/mod/direct    3/rm32/EBX    .           .             .           3/r32/EBX   .               .                 # clear EBX
+$emit-segments:line-loop:
+    # clear-stream(line)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # read-line(in, line)
+    # . . push args
+    51/push-ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  read-line/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # dump line {{{
+#?     # . write(2/stderr, "LL: ")
+#?     # . . push args
+#?     68/push  "LL: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # write-stream(2/stderr, line)
+#?     # . . push args
+#?     51/push-ECX
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . rewind-stream(line)
+#?     # . . push args
+#?     51/push-ECX
+#?     # . . call
+#?     e8/call  rewind-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # }}}
+$emit-segments:check-for-end-of-input:
+    # if (line->write == 0) break
+    81          7/subop/compare     0/mod/indirect  1/rm32/ECX    .           .             .           .           .               0/imm32           # compare *ECX
+    0f 84/jump-if-equal  $emit-segments:end/disp32
+    # offset-of-next-instruction += num-bytes(line)
+    # . EAX = num-bytes(line)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  num-bytes/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . EBX += EAX
+    01/add                          3/mod/direct    3/rm32/EBX    .           .             .           0/r32/EAX   .               .                 # add EAX to EBX
+$emit-segments:word-loop:
+    # next-word(line, word-slice)
+    # . . push args
+    52/push-EDX
+    51/push-ECX
+    # . . call
+    e8/call  next-word/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # dump word-slice {{{
+#?     # . write(2/stderr, "w: ")
+#?     # . . push args
+#?     68/push  "w: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-slice-buffered(Stderr, word-slice)
+#?     # . . push args
+#?     52/push-EDX
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  write-slice-buffered/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . flush(Stderr)
+#?     # . . push args
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  flush/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+$emit-segments:check-for-end-of-line:
+    # if (slice-empty?(word-slice)) break
+    # . EAX = slice-empty?(word-slice)
+    # . . push args
+    52/push-EDX
+    # . . call
+    e8/call  slice-empty?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . if (EAX != 0) break
+    3d/compare-EAX-and  0/imm32
+    0f 85/jump-if-not-equal  $emit-segments:next-line/disp32
+$emit-segments:check-for-comment:
+    # if (slice-starts-with?(word-slice, "#")) break
+    # . start/ESI = word-slice->start
+    8b/copy                         0/mod/indirect  2/rm32/EDX    .           .             .           6/r32/ESI   .               .                 # copy *EDX to ESI
+    # . c/EAX = *start
+    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
+    8a/copy-byte                    0/mod/indirect  6/rm32/ESI    .           .             .           0/r32/AL    .               .                 # copy byte at *ESI to AL
+    # . if (EAX == '#') break
+    3d/compare-EAX-and  0x23/imm32/hash
+    0f 84/jump-if-equal  $emit-segments:next-line/disp32
+$emit-segments:check-for-label:
+    # if is-label?(word-slice) break
+    # . EAX = is-label?(word-slice)
+    # . . push args
+    52/push-EDX
+    # . . call
+    e8/call  is-label?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . if (EAX != 0) break
+    3d/compare-EAX-and  0/imm32
+    0f 85/jump-if-not-equal  $emit-segments:line-loop/disp32
+$emit-segments:check-for-segment-header:
+    # if (slice-equal?(word-slice, "==")) break
+    # . EAX = slice-equal?(word-slice, "==")
+    # . . push args
+    68/push  "=="/imm32
+    52/push-EDX
+    # . . call
+    e8/call  slice-equal?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX != 0) break
+    3d/compare-EAX-and  0/imm32
+    0f 85/jump-if-not-equal  $emit-segments:line-loop/disp32
+$emit-segments:2-character:
+    # if (length(word-slice) != 2) goto next check
+    # . EAX = length(word-slice)
+    8b/copy                         1/mod/*+disp8   2/rm32/EDX    .           .             .           0/r32/EAX   4/disp8         .                 # copy *(EDX+4) to EAX
+    2b/subtract                     0/mod/indirect  2/rm32/EDX    .           .             .           0/r32/EAX   .               .                 # subtract *EDX from EAX
+    # . if (EAX != 2) goto next check
+    3d/compare-EAX-and  2/imm32
+    75/jump-if-not-equal  $emit-segments:check-metadata/disp8
+    # write-slice-buffered(out, word-slice)
+    # . . push args
+    52/push-EDX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write-slice-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # write-buffered(out, " ")
+    # . . push args
+    68/push  " "/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # continue
+    e9/jump  $emit-segments:word-loop/disp32
+$emit-segments:check-metadata:
+    # - if we get here, 'word-slice' must be a label to be looked up
+    # datum/EDI = next-token-from-slice(word-slice->start, word-slice->end, "/")
+    # . . push args
+    57/push-EDI
+    68/push  0x2f/imm32/slash
+    ff          6/subop/push        1/mod/*+disp8   2/rm32/EDX    .           .             .           .           4/disp8         .                 # push *(EDX+4)
+    ff          6/subop/push        0/mod/indirect  2/rm32/EDX    .           .             .           .           .               .                 # push *EDX
+    # . . call
+    e8/call  next-token-from-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
+#?     # dump word-slice {{{
+#?     # . write(2/stderr, "datum: ")
+#?     # . . push args
+#?     68/push  "datum: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-slice-buffered(Stderr, word-slice)
+#?     # . . push args
+#?     57/push-EDI
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  write-slice-buffered/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . flush(Stderr)
+#?     # . . push args
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  flush/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # info/ESI = get-slice(labels, datum, row-size=16)
+    # . EAX = get-slice(labels, datum, row-size=16)
+    # . . push args
+    68/push  0x10/imm32/row-size
+    57/push-EDI
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x14/disp8      .                 # push *(EBP+20)
+    # . . call
+    e8/call  get-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . ESI = EAX
+    89/copy                         3/mod/direct    6/rm32/ESI    .           .             .           0/r32/EAX   .               .                 # copy EAX to ESI
+$emit-segments:check-global-variable:
+#?     # dump info->segment-name {{{
+#?     # . write(2/stderr, "aa: label segment: ")
+#?     # . . push args
+#?     68/push  "aa: label segment: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, info->segment-name)
+#?     # . . push args
+#?     ff          6/subop/push        0/mod/indirect  6/rm32/ESI    .           .             .           .           .               .                 # push *ESI
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # if string-equal?(info->segment-name, "code") goto code label checks
+    # . EAX = string-equal?(info->segment-name, "code")
+    # . . push args
+    68/push  "code"/imm32
+    ff          6/subop/push        0/mod/indirect  6/rm32/ESI    .           .             .           .           .               .                 # push *ESI
+    # . . call
+    e8/call  string-equal?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX != 0) goto code label checks
+    3d/compare-EAX-and  0/imm32
+    0f 85/jump-if-not-equal  $emit-segments:check-code-label-for-imm8/disp32
+$emit-segments:check-global-variable-for-disp8:
+    # if has-metadata?(word-slice, "disp8") abort
+    # . EAX = has-metadata?(word-slice, "disp8")
+    # . . push args
+    68/push  "disp8"/imm32
+    52/push-EDX
+    # . . call
+    e8/call  has-metadata?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX != 0) abort
+    3d/compare-EAX-and  0/imm32
+    0f 85/jump-if-not-equal  $emit-segments:global-variable-abort/disp32
+$emit-segments:check-global-variable-for-imm8:
+    # if has-metadata?(word-slice, "imm8") abort
+    # . EAX = has-metadata?(word-slice, "imm8")
+    # . . push args
+    68/push  "imm8"/imm32
+    52/push-EDX
+    # . . call
+    e8/call  has-metadata?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX != 0) abort
+    3d/compare-EAX-and  0/imm32
+    0f 85/jump-if-not-equal  $emit-segments:global-variable-abort/disp32
+$emit-segments:emit-global-variable:
+    # emit-hex(out, info->address, 4)
+    # . . push args
+    68/push  4/imm32
+    ff          6/subop/push        1/mod/*+disp8   6/rm32/ESI    .           .             .           .           8/disp8         .                 # push *(ESI+8)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  emit-hex/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # continue
+    e9/jump  $emit-segments:word-loop/disp32
+$emit-segments:check-code-label-for-imm8:
+    # if (has-metadata?(word-slice, "imm8")) abort
+    # . EAX = has-metadata?(EDX, "imm8")
+    # . . push args
+    68/push  "imm8"/imm32
+    52/push-EDX
+    # . . call
+    e8/call  has-metadata?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX != 0) abort
+    3d/compare-EAX-and  0/imm32
+    0f 85/jump-if-not-equal  $emit-segments:imm8-abort/disp32
+$emit-segments:check-code-label-for-imm32:
+    # if (!has-metadata?(word-slice, "imm32")) goto next check
+    # . EAX = has-metadata?(EDX, "imm32")
+    # . . push args
+    68/push  "imm32"/imm32
+    52/push-EDX
+    # . . call
+    e8/call  has-metadata?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX == 0) goto next check
+    3d/compare-EAX-and  0/imm32
+    74/jump-if-equal  $emit-segments:check-code-label-for-disp8/disp8
+#?     # dump info->address {{{
+#?     # . write(2/stderr, "info->address: ")
+#?     # . . push args
+#?     68/push  "info->address: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . print-int32-buffered(Stderr, info->address)
+#?     # . . push args
+#?     ff          6/subop/push        1/mod/*+disp8   6/rm32/ESI    .           .             .           .           8/disp8         .                 # push *(ESI+8)
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  print-int32-buffered/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . flush(Stderr)
+#?     # . . push args
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  flush/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+$emit-segments:emit-code-label-imm32:
+    # emit-hex(out, info->address, 4)
+    # . . push args
+    68/push  4/imm32
+    ff          6/subop/push        1/mod/*+disp8   6/rm32/ESI    .           .             .           .           8/disp8         .                 # push *(ESI+8)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  emit-hex/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # continue
+    e9/jump  $emit-segments:word-loop/disp32
+$emit-segments:check-code-label-for-disp8:
+    # if (!has-metadata?(word-slice, "disp8")) goto next check
+    # . EAX = has-metadata?(EDX, "disp8")
+    # . . push args
+    68/push  "disp8"/imm32
+    52/push-EDX
+    # . . call
+    e8/call  has-metadata?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX == 0) goto next check
+    3d/compare-EAX-and  0/imm32
+    74/jump-if-equal  $emit-segments:check-code-label-for-disp32/disp8
+$emit-segments:emit-code-label-disp8:
+    # emit-hex(out, info->offset - offset-of-next-instruction, 1)
+    # . . push args
+    68/push  1/imm32
+    8b/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           0/r32/EAX   4/disp8         .                 # copy *(ESI+4) to EAX
+    29/subtract                     3/mod/direct    0/rm32/EAX    .           .             .           3/r32/EBX   .               .                 # subtract EBX from EAX
+    50/push-EAX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  emit-hex/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # continue
+    e9/jump  $emit-segments:word-loop/disp32
+$emit-segments:check-code-label-for-disp32:
+    # if (!has-metadata?(word-slice, "disp32")) abort
+    # . EAX = has-metadata?(EDX, "disp32")
+    # . . push args
+    68/push  "disp32"/imm32
+    52/push-EDX
+    # . . call
+    e8/call  has-metadata?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX == 0) abort
+    3d/compare-EAX-and  0/imm32
+    0f 84/jump-if-equal  $emit-segments:abort/disp32
+$emit-segments:emit-code-label-disp32:
+    # emit-hex(out, info->offset - offset-of-next-instruction, 4)
+    # . . push args
+    68/push  4/imm32
+    8b/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           0/r32/EAX   4/disp8         .                 # copy *(ESI+4) to EAX
+    29/subtract                     3/mod/direct    0/rm32/EAX    .           .             .           3/r32/EBX   .               .                 # subtract EBX from EAX
+    50/push-EAX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  emit-hex/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # continue
+    e9/jump  $emit-segments:word-loop/disp32
+$emit-segments:next-line:
+    # write-buffered(out, "\n")
+    # . . push args
+    68/push  Newline/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # loop
+    e9/jump  $emit-segments:line-loop/disp32
+$emit-segments:end:
+    # . reclaim locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x21c/imm32       # add to ESP
+    # . restore registers
+    5f/pop-to-EDI
+    5e/pop-to-ESI
+    5b/pop-to-EBX
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+$emit-segments:global-variable-abort:
+    # . _write(2/stderr, error)
+    # . . push args
+    68/push  "emit-segments: must refer to global variables with /disp32 or /imm32"/imm32
+    68/push  2/imm32/stderr
+    # . . call
+    e8/call  _write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . syscall(exit, 1)
+    bb/copy-to-EBX  1/imm32
+    b8/copy-to-EAX  1/imm32/exit
+    cd/syscall  0x80/imm8
+    # never gets here
+
+$emit-segments:imm8-abort:
+    # . _write(2/stderr, error)
+    # . . push args
+    68/push  "emit-segments: cannot refer to code labels with /imm8"/imm32
+    68/push  2/imm32/stderr
+    # . . call
+    e8/call  _write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . syscall(exit, 1)
+    bb/copy-to-EBX  1/imm32
+    b8/copy-to-EAX  1/imm32/exit
+    cd/syscall  0x80/imm8
+    # never gets here
+
+$emit-segments:abort:
+    # print(stderr, "missing metadata in " word-slice)
+    # . _write(2/stderr, "missing metadata in word ")
+    # . . push args
+    68/push  "emit-segments: missing metadata in "/imm32
+    68/push  2/imm32/stderr
+    # . . call
+    e8/call  _write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write-slice-buffered(Stderr, word-slice)
+    # . . push args
+    52/push-EDX
+    68/push  Stderr/imm32
+    # . . call
+    e8/call  write-slice-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . flush(Stderr)
+    # . . push args
+    68/push  Stderr/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . syscall(exit, 1)
+    bb/copy-to-EBX  1/imm32
+    b8/copy-to-EAX  1/imm32/exit
+    cd/syscall  0x80/imm8
+    # never gets here
+
+test-emit-segments-global-variable:
+    # global variables always convert to absolute addresses, regardless of metadata
+    #
+    # input:
+    #   in:
+    #     == code 0x1000
+    #     ab cd ef gh
+    #     ij x/disp32
+    #     == data 0x2000
+    #     00
+    #     x:
+    #       34
+    #   segments:
+    #     - 'code': {0x1074, 0, 9}
+    #     - 'data': {0x2079, 5, 2}
+    #   labels:
+    #     - 'x': {'data', 1, 0x207a}
+    #
+    # output:
+    #   ab cd ef gh
+    #   ij 7a 20 00 00
+    #   00
+    #   34
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . var segments/ECX = stream(10 * 16)
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xa0/imm32        # subtract from ESP
+    68/push  0xa0/imm32/length
+    68/push  0/imm32/read
+    68/push  0/imm32/write
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # . var labels/EDX = stream(512 * 16)
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x2000/imm32      # subtract from ESP
+    68/push  0x2000/imm32/length
+    68/push  0/imm32/read
+    68/push  0/imm32/write
+    89/copy                         3/mod/direct    2/rm32/EDX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EDX
+    # initialize input
+    # . write(_test-input-stream, "== code 0x1000\n")
+    # . . push args
+    68/push  "== code 0x1000\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "ab cd ef gh\n")
+    # . . push args
+    68/push  "ab cd ef gh\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "ij x/disp32\n")
+    # . . push args
+    68/push  "ij x/disp32\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "== data 0x2000\n")
+    # . . push args
+    68/push  "== data 0x2000\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "00\n")
+    # . . push args
+    68/push  "00\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "x:\n")
+    # . . push args
+    68/push  "x:\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "34\n")
+    # . . push args
+    68/push  "34\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . stream-add4(segments, "code", 0x1074, 0, 9)
+    68/push  9/imm32/segment-size
+    68/push  0/imm32/file-offset
+    68/push  0x1074/imm32/start-address
+    68/push  "code"/imm32/segment-name
+    51/push-ECX
+    # . . call
+    e8/call  stream-add4/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x14/imm32        # add to ESP
+    # . stream-add4(segments, "data", 0x2079, 5, 2)
+    68/push  1/imm32/segment-size
+    68/push  5/imm32/file-offset
+    68/push  0x2079/imm32/start-address
+    68/push  "data"/imm32/segment-name
+    51/push-ECX
+    # . . call
+    e8/call  stream-add4/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x14/imm32        # add to ESP
+    # . stream-add4(labels, "x", "data", 1, 0x207a)
+    68/push  0x207a/imm32/label-address
+    68/push  1/imm32/segment-offset
+    68/push  "data"/imm32/segment-name
+    68/push  "x"/imm32/label-name
+    52/push-EDX
+    # . . call
+    e8/call  stream-add4/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x14/imm32        # add to ESP
+    # component under test
+    # . emit-segments(_test-input-stream, _test-output-buffered-file, segments, labels)
+    # . . push args
+    52/push-EDX
+    51/push-ECX
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  emit-segments/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
+    # checks
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "result: ^")
+#?     # . . push args
+#?     68/push  "result: ^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . rewind-stream(_test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     # . . call
+#?     e8/call  rewind-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # }}}
+    # . check-next-stream-line-equal(_test-output-stream, "ab cd ef gh ", msg)
+    # . . push args
+    68/push  "F - test-emit-segments-global-variable/0"/imm32
+    68/push  "ab cd ef gh "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "ij 7a 20 00 00 ", msg)
+    # . . push args
+    68/push  "F - test-emit-segments-global-variable/1"/imm32
+    68/push  "ij 7a 20 00 00 "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "00 ", msg)
+    # . . push args
+    68/push  "F - test-emit-segments-global-variable/2"/imm32
+    68/push  "00 "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "34 ", msg)
+    # . . push args
+    68/push  "F - test-emit-segments-global-variable/3"/imm32
+    68/push  "34 "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-emit-segments-code-label:
+    # labels usually convert to displacements
+    #
+    # input:
+    #   in:
+    #     == code 0x1000
+    #     ab cd
+    #     l1:
+    #       ef gh
+    #       ij l1/disp32
+    #   segments:
+    #     - 'code': {0x1054, 0, 9}
+    #   labels:
+    #     - 'l1': {'code', 2, 0x1056}
+    #
+    # output:
+    #   ab cd
+    #   ef gh
+    #   ij f9 ff ff ff  # -7
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . var segments/ECX = stream(10 * 16)
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xa0/imm32        # subtract from ESP
+    68/push  0xa0/imm32/length
+    68/push  0/imm32/read
+    68/push  0/imm32/write
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # . var labels/EDX = stream(512 * 16)
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x2000/imm32      # subtract from ESP
+    68/push  0x2000/imm32/length
+    68/push  0/imm32/read
+    68/push  0/imm32/write
+    89/copy                         3/mod/direct    2/rm32/EDX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EDX
+    # initialize input
+    # . write(_test-input-stream, "== code 0x1000\n")
+    # . . push args
+    68/push  "== code 0x1000\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "ab cd\n")
+    # . . push args
+    68/push  "ab cd\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "l1:\n")
+    # . . push args
+    68/push  "l1:\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "  ef gh\n")
+    # . . push args
+    68/push  "  ef gh\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "  ij l1/disp32\n")
+    # . . push args
+    68/push  "  ij l1/disp32\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . stream-add4(segments, "code", 0x1054, 0, 9)
+    68/push  9/imm32/segment-size
+    68/push  0/imm32/file-offset
+    68/push  0x1054/imm32/start-address
+    68/push  "code"/imm32/segment-name
+    51/push-ECX
+    # . . call
+    e8/call  stream-add4/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x14/imm32        # add to ESP
+    # . stream-add4(labels, "l1", "code", 2, 0x1056)
+    68/push  0x1056/imm32/label-address
+    68/push  2/imm32/segment-offset
+    68/push  "code"/imm32/segment-name
+    68/push  "l1"/imm32/label-name
+    52/push-EDX
+    # . . call
+    e8/call  stream-add4/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x14/imm32        # add to ESP
+    # component under test
+    # . emit-segments(_test-input-stream, _test-output-buffered-file, segments, labels)
+    # . . push args
+    52/push-EDX
+    51/push-ECX
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  emit-segments/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
+    # checks
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "result: ^")
+#?     # . . push args
+#?     68/push  "result: ^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . rewind-stream(_test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     # . . call
+#?     e8/call  rewind-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # }}}
+    # . check-next-stream-line-equal(_test-output-stream, "ab cd ", msg)
+    # . . push args
+    68/push  "F - test-emit-segments-code-label/0"/imm32
+    68/push  "ab cd "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "ef gh ", msg)
+    # . . push args
+    68/push  "F - test-emit-segments-code-label/1"/imm32
+    68/push  "ef gh "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "ij f9 ff ff ff ", msg)
+    # . . push args
+    68/push  "F - test-emit-segments-code-label/2"/imm32
+    68/push  "ij f9 ff ff ff "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-emit-segments-code-label-absolute:
+    # labels can also convert to absolute addresses
+    #
+    # input:
+    #   in:
+    #     == code 0x1000
+    #     ab cd
+    #     l1:
+    #       ef gh
+    #       ij l1/imm32
+    #   segments:
+    #     - 'code': {0x1054, 0, 9}
+    #   labels:
+    #     - 'l1': {'code', 2, 0x1056}
+    #
+    # output:
+    #   ab cd
+    #   ef gh
+    #   ij 56 10 00 00
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-buffered-file+4)
+    # . . push args
+    b8/copy-to-EAX  _test-output-buffered-file/imm32
+    05/add-to-EAX  4/imm32
+    50/push-EAX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . var segments/ECX = stream(10 * 16)
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xa0/imm32        # subtract from ESP
+    68/push  0xa0/imm32/length
+    68/push  0/imm32/read
+    68/push  0/imm32/write
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # . var labels/EDX = stream(512 * 16)
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x2000/imm32      # subtract from ESP
+    68/push  0x2000/imm32/length
+    68/push  0/imm32/read
+    68/push  0/imm32/write
+    89/copy                         3/mod/direct    2/rm32/EDX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EDX
+    # initialize input
+    # . write(_test-input-stream, "== code 0x1000\n")
+    # . . push args
+    68/push  "== code 0x1000\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "ab cd\n")
+    # . . push args
+    68/push  "ab cd\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "l1:\n")
+    # . . push args
+    68/push  "l1:\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "  ef gh\n")
+    # . . push args
+    68/push  "  ef gh\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . write(_test-input-stream, "  ij l1/imm32\n")
+    # . . push args
+    68/push  "  ij l1/imm32\n"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . stream-add4(segments, "code", 0x1054, 0, 9)
+    68/push  9/imm32/segment-size
+    68/push  0/imm32/file-offset
+    68/push  0x1054/imm32/start-address
+    68/push  "code"/imm32/segment-name
+    51/push-ECX
+    # . . call
+    e8/call  stream-add4/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x14/imm32        # add to ESP
+    # . stream-add4(labels, "l1", "code", 2, 0x1056)
+    68/push  0x1056/imm32/label-address
+    68/push  2/imm32/segment-offset
+    68/push  "code"/imm32/segment-name
+    68/push  "l1"/imm32/label-name
+    52/push-EDX
+    # . . call
+    e8/call  stream-add4/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x14/imm32        # add to ESP
+    # component under test
+    # . emit-segments(_test-input-stream, _test-output-buffered-file, segments, labels)
+    # . . push args
+    52/push-EDX
+    51/push-ECX
+    68/push  _test-output-buffered-file/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  emit-segments/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
+    # checks
+    # . flush(_test-output-buffered-file)
+    # . . push args
+    68/push  _test-output-buffered-file/imm32
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # dump output {{{
+#?     # . write(2/stderr, "result: ^")
+#?     # . . push args
+#?     68/push  "result: ^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, _test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . rewind-stream(_test-output-stream)
+#?     # . . push args
+#?     68/push  _test-output-stream/imm32
+#?     # . . call
+#?     e8/call  rewind-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # }}}
+    # . check-next-stream-line-equal(_test-output-stream, "ab cd ", msg)
+    # . . push args
+    68/push  "F - test-emit-segments-code-label-absolute/0"/imm32
+    68/push  "ab cd "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "ef gh ", msg)
+    # . . push args
+    68/push  "F - test-emit-segments-code-label-absolute/1"/imm32
+    68/push  "ef gh "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . check-next-stream-line-equal(_test-output-stream, "ij f9 ff ff ff ", msg)
+    # . . push args
+    68/push  "F - test-emit-segments-code-label-absolute/2"/imm32
+    68/push  "ij 56 10 00 00 "/imm32
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  check-next-stream-line-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+emit-headers:  # out : (address buffered-file), segments : (address stream {string, segment-info}), labels : (address stream {string, label-info})
+    # pseudocode:
+    #   emit-elf-header(out, segments, labels)
+    #   curr-segment = segments->data
+    #   max = segments->data + segments->write
+    #   while true
+    #     if (curr-segment >= max) break
+    #     emit-elf-program-header-entry(out, curr-segment)
+    #     curr-segment += 16                        # size of a row
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+    51/push-ECX
+#?     # write(2/stderr, "emit-elf-header\n") {{{
+#?     # . . push args
+#?     68/push  "emit-elf-header\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # emit-elf-header(out, segments, labels)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x10/disp8      .                 # push *(EBP+16)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  emit-elf-header/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # EAX = segments
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           0/r32/EAX   0xc/disp8       .                 # copy *(EBP+12) to EAX
+    # ECX = segments->write
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    # curr-segment/EAX = segments->data
+    8d/copy-address                 1/mod/*+disp8   0/rm32/EAX    .           .             .           0/r32/EAX   0xc/disp8       .                 # copy EAX+12 to EAX
+    # max/ECX = segments->data + segments->write
+    01/add                          3/mod/direct    1/rm32/ECX    .           .             .           0/r32/EAX   .               .                 # add EAX to ECX
+$emit-headers:loop:
+    # if (curr-segment >= max) break
+    39/compare                      3/mod/direct    0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # compare EAX with ECX
+    0f 83/jump-if-greater-or-equal-unsigned  $emit-headers:end/disp32
+#?     # dump curr-segment->name {{{
+#?     # . write(2/stderr, "about to emit ph entry: segment->name: ")
+#?     # . . push args
+#?     68/push  "about to emit ph entry: segment->name: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . clear-stream(Stderr+4)
+#?     # . . save EAX
+#?     50/push-EAX
+#?     # . . push args
+#?     b8/copy-to-EAX  Stderr/imm32
+#?     05/add-to-EAX  4/imm32
+#?     50/push-EAX
+#?     # . . call
+#?     e8/call  clear-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . . restore EAX
+#?     58/pop-to-EAX
+#?     # . print-int32-buffered(Stderr, &curr-segment)
+#?     # . . push args
+#?     50/push-EAX
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  print-int32-buffered/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . flush(Stderr)
+#?     # . . push args
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  flush/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . write(2/stderr, " -> ")
+#?     # . . push args
+#?     68/push  " -> "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . print-int32-buffered(Stderr, curr-segment->name)
+#?     # . . push args
+#?     ff          6/subop/push        0/mod/indirect  0/rm32/EAX    .           .             .           .           .               .                 # push *EAX
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  print-int32-buffered/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . flush(Stderr)
+#?     # . . push args
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  flush/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . write(2/stderr, "\n")
+#?     # . . push args
+#?     68/push  "\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+#?     # write(2/stderr, "emit-segment-header\n") {{{
+#?     # . . push args
+#?     68/push  "emit-segment-header\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # emit-elf-program-header-entry(out, curr-segment)
+    # . . push args
+    50/push-EAX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  emit-elf-program-header-entry/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # curr-segment += 16                        # size of a row
+    81          0/subop/add         3/mod/direct    0/rm32/EAX    .           .             .           .           .               0x10/imm32        # add to EAX
+    e9/jump  $emit-headers:loop/disp32
+$emit-headers:end:
+    # . restore registers
+    59/pop-to-ECX
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+emit-elf-header:  # out : (address buffered-file), segments : (address stream {string, segment-info}), labels : (address stream {string, label-info})
+    # pseudocode
+    #   *Elf_e_entry = get(labels, "Entry")->address
+    #   *Elf_e_phnum = segments->write / 16         # size of a row
+    #   emit-hex-array(out, Elf_header)
+    #   write-buffered(out, "\n")
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+    51/push-ECX
+    52/push-EDX  # just because we need to call idiv
+    # *Elf_e_entry = get(labels, "Entry")->address
+    # . EAX = labels
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           0/r32/EAX   0x10/disp8      .                 # copy *(EBP+16) to EAX
+    # . label-info/EAX = get(labels, "Entry", row-size=16)
+    # . . push args
+    68/push  0x10/imm32/row-size
+    68/push  "Entry"/imm32
+    50/push-EAX
+    # . . call
+    e8/call  get/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . EAX = label-info->address
+    8b/copy                         1/mod/*+disp8   0/rm32/EAX    .           .             .           0/r32/EAX   8/disp8         .                 # copy *(EAX+8) to EAX
+    # . *Elf_e_entry = EAX
+    89/copy                         0/mod/indirect  5/rm32/.disp32            .             .           0/r32/EAX   Elf_e_entry/disp32                # copy EAX to *Elf_e_entry
+    # *Elf_e_phnum = segments->write / 0x10
+    # . EAX = segments
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           0/r32/EAX   0xc/disp8       .                 # copy *(EBP+12) to EAX
+    # . len/EAX = segments->write
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # copy *EAX to EAX
+    # . EAX = len / 0x10  (destroying EDX)
+    b9/copy-to-ECX  0x10/imm32
+    31/xor                          3/mod/direct    2/rm32/EDX    .           .             .           2/r32/EDX   .               .                 # clear EDX
+    f7          7/subop/idiv        3/mod/direct    1/rm32/ECX    .           .             .           .           .               .                 # divide EDX:EAX by ECX, storing quotient in EAX and remainder in EDX
+    # . *Elf_e_phnum = EAX
+    89/copy                         0/mod/indirect  5/rm32/.disp32            .             .           0/r32/EAX   Elf_e_phnum/disp32                # copy EAX to *Elf_e_phnum
+    # emit-hex-array(out, Elf_header)
+    # . . push args
+    68/push  Elf_header/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  emit-hex-array/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # write-buffered(out, "\n")
+    # . . push args
+    68/push  "\n"/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  write-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+$emit-elf-header:end:
+    # . restore registers
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+emit-elf-program-header-entry:  # out : (address buffered-file), curr-segment : (address {string, segment-info})
+    # pseudocode:
+    #   *Elf_p_offset = curr-segment->file-offset
+    #   *Elf_p_vaddr = curr-segment->address
+    #   *Elf_p_paddr = curr-segment->address
+    #   *Elf_p_filesz = curr-segment->size
+    #   *Elf_p_memsz = curr-segment->size
+    #   if curr-segment->name == "code"
+    #     *Elf_p_flags = 5  # r-x
+    #   else
+    #     *Elf_p_flags = 6  # rw-
+    #   emit-hex-array(out, Elf_program_header_entry)
+    #   write-buffered(out, "\n")
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+    56/push-ESI
+    # ESI = curr-segment
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   0xc/disp8       .                 # copy *(EBP+12) to ESI
+    # *Elf_p_offset = curr-segment->file-offset
+    # . EAX = curr-segment->file-offset
+    8b/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           0/r32/EAX   8/disp8         .                 # copy *(ESI+8) to EAX
+    # . *Elf_p_offset = EAX
+    89/copy                         0/mod/indirect  5/rm32/.disp32            .             .           0/r32/EAX   Elf_p_offset/disp32               # copy EAX to *Elf_p_offset
+    # *Elf_p_vaddr = curr-segment->address
+    # . EAX = curr-segment->address
+    8b/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           0/r32/EAX   4/disp8         .                 # copy *(ESI+4) to EAX
+    # . *Elf_p_vaddr = EAX
+    89/copy                         0/mod/indirect  5/rm32/.disp32            .             .           0/r32/EAX   Elf_p_vaddr/disp32                # copy EAX to *Elf_p_vaddr
+    # *Elf_p_paddr = curr-segment->address
+    89/copy                         0/mod/indirect  5/rm32/.disp32            .             .           0/r32/EAX   Elf_p_paddr/disp32                # copy EAX to *Elf_p_paddr
+    # *Elf_p_filesz = curr-segment->size
+    # . EAX = curr-segment->size
+    8b/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           0/r32/EAX   0xc/disp8       .                 # copy *(ESI+12) to EAX
+    # . *Elf_p_filesz = EAX
+    89/copy                         0/mod/indirect  5/rm32/.disp32            .             .           0/r32/EAX   Elf_p_filesz/disp32               # copy EAX to *Elf_p_filesz
+    # *Elf_p_memsz = curr-segment->size
+    89/copy                         0/mod/indirect  5/rm32/.disp32            .             .           0/r32/EAX   Elf_p_memsz/disp32                # copy EAX to *Elf_p_memsz
+    # if (!string-equal?(curr-segment->name, "code") goto next check
+    # . EAX = curr-segment->name
+    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           0/r32/EAX   .               .                 # copy *ESI to EAX
+    # . EAX = string-equal?(curr-segment->name, "code")
+    # . . push args
+    68/push  "code"/imm32
+    50/push-EAX
+    # . . call
+    e8/call  string-equal?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX == 0) goto next check
+    3d/compare-EAX-and  0/imm32
+    74/jump-if-equal  $emit-elf-program-header-entry:data/disp8
+    # *Elf_p_flags = r-x
+    c7          0/subop/copy        0/mod/indirect  5/rm32/.disp32            .             .           .           Elf_p_flags/disp32  5/imm32       # copy to *Elf_p_flags
+    eb/jump  $emit-elf-program-header-entry:really-emit/disp8
+$emit-elf-program-header-entry:data:
+    # otherwise *Elf_p_flags = rw-
+    c7          0/subop/copy        0/mod/indirect  5/rm32/.disp32            .             .           .           Elf_p_flags/disp32  6/imm32       # copy to *Elf_p_flags
+$emit-elf-program-header-entry:really-emit:
+    # emit-hex-array(out, Elf_program_header_entry)
+    # . . push args
+    68/push  Elf_program_header_entry/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  emit-hex-array/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # write-buffered(out, "\n")
+    # . . push args
+    68/push  "\n"/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  write-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+$emit-elf-program-header-entry:end:
+    # . restore registers
+    5e/pop-to-ESI
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+# - some helpers for tests
+
+stream-add4:  # in : (address stream byte), key : address, val1 : address, val2 : address, val3 : address
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+    51/push-ECX
+    52/push-EDX
+    56/push-ESI
+    # ESI = in
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   8/disp8         .                 # copy *(EBP+8) to ESI
+    # curr/EAX = in->data + in->write
+    # . EAX = in->write
+    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           0/r32/EAX   .               .                 # copy *ESI to EAX
+    # . EAX = ESI+EAX+12
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    6/base/ESI  0/index/EAX   .           0/r32/EAX   0xc/disp8       .                 # copy ESI+EAX+12 to EAX
+    # max/EDX = in->data + in->length
+    # . EDX = in->length
+    8b/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           2/r32/EDX   8/disp8         .                 # copy *(ESI+8) to EDX
+    # . EDX = ESI+EDX+12
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    6/base/ESI  2/index/EDX   .           2/r32/EDX   0xc/disp8       .                 # copy ESI+EDX+12 to EDX
+    # if (curr >= max) abort
+    39/compare                      3/mod/direct    0/rm32/EAX    .           .             .           2/r32/EDX   .               .                 # compare EAX with EDX
+    73/jump-if-greater-or-equal-unsigned  $stream-add4:abort/disp8
+    # *curr = key
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .                         1/r32/ECX   0xc/disp8       .                 # copy *(EBP+12) to ECX
+    89/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy ECX to *EAX
+    # curr += 4
+    05/add-to-EAX  4/imm32
+    # if (curr >= max) abort
+    39/compare                      3/mod/direct    0/rm32/EAX    .           .             .           2/r32/EDX   .               .                 # compare EAX with EDX
+    73/jump-if-greater-or-equal-unsigned  $stream-add4:abort/disp8
+    # *curr = val1
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .                         1/r32/ECX   0x10/disp8      .                 # copy *(EBP+16) to ECX
+    89/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy ECX to *EAX
+    # curr += 4
+    05/add-to-EAX  4/imm32
+    # if (curr >= max) abort
+    39/compare                      3/mod/direct    0/rm32/EAX    .           .             .           2/r32/EDX   .               .                 # compare EAX with EDX
+    73/jump-if-greater-or-equal-unsigned  $stream-add4:abort/disp8
+    # *curr = val2
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .                         1/r32/ECX   0x14/disp8      .                 # copy *(EBP+20) to ECX
+    89/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy ECX to *EAX
+    # curr += 4
+    05/add-to-EAX  4/imm32
+    # if (curr >= max) abort
+    39/compare                      3/mod/direct    0/rm32/EAX    .           .             .           2/r32/EDX   .               .                 # compare EAX with EDX
+    73/jump-if-greater-or-equal-unsigned  $stream-add4:abort/disp8
+    # *curr = val3
+    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .                         1/r32/ECX   0x18/disp8      .                 # copy *(EBP+24) to ECX
+    89/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy ECX to *EAX
+    # in->write += 16
+    81          0/subop/add         0/mod/indirect  6/rm32/ESI    .           .             .           .           .               0x10/imm32        # add to *ESI
+$stream-add4:end:
+    # . restore registers
+    5e/pop-to-ESI
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+$stream-add4:abort:
+    # . _write(2/stderr, error)
+    # . . push args
+    68/push  "overflow in stream-add4\n"/imm32
+    68/push  2/imm32/stderr
+    # . . call
+    e8/call  _write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . syscall(exit, 1)
+    bb/copy-to-EBX  1/imm32
+    b8/copy-to-EAX  1/imm32/exit
+    cd/syscall  0x80/imm8
+    # never gets here
+
+# some variants of 'trace' that take multiple arguments in different combinations of types:
+#   n: int
+#   c: character [4-bytes, will eventually be UTF-8]
+#   s: (address string)
+#   l: (address slice)
+# one gotcha: 's5' must not be empty
+
+trace-sssns:  # s1 : (address string), s2 : (address string), s3 : (address string), n4 : int, s5 : (address string)
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # write(*Trace-stream, s1)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Trace-stream/disp32               # push *Trace-stream
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # write(*Trace-stream, s2)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Trace-stream/disp32               # push *Trace-stream
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # write(*Trace-stream, s3)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x10/disp8      .                 # push *(EBP+16)
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Trace-stream/disp32               # push *Trace-stream
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # print-int32(*Trace-stream, n4)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x14/disp8      .                 # push *(EBP+20)
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Trace-stream/disp32               # push *Trace-stream
+    # . . call
+    e8/call  print-int32/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # trace(s5)  # implicitly adds a newline and finalizes the trace line
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x18/disp8      .                 # push *(EBP+24)
+    # . . call
+    e8/call  trace/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+$trace-sssns:end:
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-trace-sssns:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . *Trace-stream->write = 0
+    8b/copy                         0/mod/indirect  5/rm32/.disp32            .             .           0/r32/EAX   Trace-stream/disp32               # copy *Trace-stream to EAX
+    c7          0/subop/copy        0/mod/direct    0/rm32/EAX    .           .             .           .           .               0/imm32           # clear *EAX
+    # trace-sssns("A" "b" "c " 3 " e")
+    # . . push args
+    68/push  " e"/imm32
+    68/push  3/imm32
+    68/push  "c "/imm32
+    68/push  "b"/imm32
+    68/push  "A"/imm32
+    # . . call
+    e8/call  trace-sssns/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x14/imm32        # add to ESP
+#?     # dump *Trace-stream {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, *Trace-stream)
+#?     # . . push args
+#?     ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Trace-stream/disp32               # push *Trace-stream
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # check-trace-contains("Abc 0x00000003 e")
+    # . . push args
+    68/push  "F - test-trace-sssns"/imm32
+    68/push  "Abc 0x00000003 e"/imm32
+    # . . call
+    e8/call  check-trace-contains/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+trace-snsns:  # s1 : (address string), n2 : int, s3 : (address string), n4 : int, s5 : (address string)
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # write(*Trace-stream, s1)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Trace-stream/disp32               # push *Trace-stream
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # print-int32(*Trace-stream, n2)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Trace-stream/disp32               # push *Trace-stream
+    # . . call
+    e8/call  print-int32/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # write(*Trace-stream, s3)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x10/disp8      .                 # push *(EBP+16)
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Trace-stream/disp32               # push *Trace-stream
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # print-int32(*Trace-stream, n4)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x14/disp8      .                 # push *(EBP+20)
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Trace-stream/disp32               # push *Trace-stream
+    # . . call
+    e8/call  print-int32/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # trace(s5)  # implicitly adds a newline and finalizes the trace line
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x18/disp8      .                 # push *(EBP+24)
+    # . . call
+    e8/call  trace/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+$trace-snsns:end:
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-trace-snsns:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . *Trace-stream->write = 0
+    8b/copy                         0/mod/indirect  5/rm32/.disp32            .             .           0/r32/EAX   Trace-stream/disp32               # copy *Trace-stream to EAX
+    c7          0/subop/copy        0/mod/direct    0/rm32/EAX    .           .             .           .           .               0/imm32           # clear *EAX
+    # trace-snsns("A " 2 " c " 3 " e")
+    # . . push args
+    68/push  " e"/imm32
+    68/push  3/imm32
+    68/push  " c "/imm32
+    68/push  2/imm32
+    68/push  "A "/imm32
+    # . . call
+    e8/call  trace-snsns/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x14/imm32        # add to ESP
+#?     # dump *Trace-stream {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, *Trace-stream)
+#?     # . . push args
+#?     ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Trace-stream/disp32               # push *Trace-stream
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # check-trace-contains("Abc 0x00000003 e")
+    # . . push args
+    68/push  "F - test-trace-snsns"/imm32
+    68/push  "A 0x00000002 c 0x00000003 e"/imm32
+    # . . call
+    e8/call  check-trace-contains/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+trace-slsls:  # s1 : (address string), l2 : (address slice), s3 : (address string), l4 : (address slice), s5 : (address string)
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # write(*Trace-stream, s1)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Trace-stream/disp32               # push *Trace-stream
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # write-slice(*Trace-stream, l2)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Trace-stream/disp32               # push *Trace-stream
+    # . . call
+    e8/call  write-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # write(*Trace-stream, s3)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x10/disp8      .                 # push *(EBP+16)
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Trace-stream/disp32               # push *Trace-stream
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # write-slice(*Trace-stream, l4)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x14/disp8      .                 # push *(EBP+20)
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Trace-stream/disp32               # push *Trace-stream
+    # . . call
+    e8/call  write-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # trace(s5)  # implicitly adds a newline and finalizes the trace line
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x18/disp8      .                 # push *(EBP+24)
+    # . . call
+    e8/call  trace/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+$trace-slsls:end:
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-trace-slsls:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . *Trace-stream->write = 0
+    8b/copy                         0/mod/indirect  5/rm32/.disp32            .             .           0/r32/EAX   Trace-stream/disp32               # copy *Trace-stream to EAX
+    c7          0/subop/copy        0/mod/direct    0/rm32/EAX    .           .             .           .           .               0/imm32           # clear *EAX
+    # (EAX..ECX) = "b"
+    b8/copy-to-EAX  "b"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # var b/EBX : (address slice) = {EAX, ECX}
+    51/push-ECX
+    50/push-EAX
+    89/copy                         3/mod/direct    3/rm32/EBX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBX
+    # (EAX..ECX) = "d"
+    b8/copy-to-EAX  "d"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # var d/EDX : (address slice) = {EAX, ECX}
+    51/push-ECX
+    50/push-EAX
+    89/copy                         3/mod/direct    2/rm32/EDX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EDX
+    # trace-slsls("A" b "c" d "e")
+    # . . push args
+    68/push  "e"/imm32
+    52/push-EDX
+    68/push  "c"/imm32
+    53/push-EBX
+    68/push  "A"/imm32
+    # . . call
+    e8/call  trace-slsls/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x14/imm32        # add to ESP
+#?     # dump *Trace-stream {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, *Trace-stream)
+#?     # . . push args
+#?     ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Trace-stream/disp32               # push *Trace-stream
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # check-trace-contains("Abcde")
+    # . . push args
+    68/push  "F - test-trace-slsls"/imm32
+    68/push  "Abcde"/imm32
+    # . . call
+    e8/call  check-trace-contains/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+trace-slsns:  # s1 : (address string), l2 : (address slice), s3 : (address string), n4 : int, s5 : (address string)
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # write(*Trace-stream, s1)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Trace-stream/disp32               # push *Trace-stream
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # write-slice(*Trace-stream, l2)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Trace-stream/disp32               # push *Trace-stream
+    # . . call
+    e8/call  write-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # write(*Trace-stream, s3)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x10/disp8      .                 # push *(EBP+16)
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Trace-stream/disp32               # push *Trace-stream
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # print-int32(*Trace-stream, n4)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x14/disp8      .                 # push *(EBP+20)
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Trace-stream/disp32               # push *Trace-stream
+    # . . call
+    e8/call  print-int32/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # trace(s5)  # implicitly adds a newline and finalizes the trace line
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x18/disp8      .                 # push *(EBP+24)
+    # . . call
+    e8/call  trace/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+$trace-slsns:end:
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-trace-slsns:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . *Trace-stream->write = 0
+    8b/copy                         0/mod/indirect  5/rm32/.disp32            .             .           0/r32/EAX   Trace-stream/disp32               # copy *Trace-stream to EAX
+    c7          0/subop/copy        0/mod/direct    0/rm32/EAX    .           .             .           .           .               0/imm32           # clear *EAX
+    # (EAX..ECX) = "b"
+    b8/copy-to-EAX  "b"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # var b/EBX : (address slice) = {EAX, ECX}
+    51/push-ECX
+    50/push-EAX
+    89/copy                         3/mod/direct    3/rm32/EBX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBX
+    # trace-slsls("A" b "c " 3 " e")
+    # . . push args
+    68/push  " e"/imm32
+    68/push  3/imm32
+    68/push  "c "/imm32
+    53/push-EBX
+    68/push  "A"/imm32
+    # . . call
+    e8/call  trace-slsns/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x14/imm32        # add to ESP
+#?     # dump *Trace-stream {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, *Trace-stream)
+#?     # . . push args
+#?     ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Trace-stream/disp32               # push *Trace-stream
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # check-trace-contains("Abc 0x00000003 e")
+    # . . push args
+    68/push  "F - test-trace-slsls"/imm32
+    68/push  "Abc 0x00000003 e"/imm32
+    # . . call
+    e8/call  check-trace-contains/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+trace-slsss:  # s1 : (address string), l2 : (address slice), s3 : (address string), s4 : (address string), s5 : (address string)
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # write(*Trace-stream, s1)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Trace-stream/disp32               # push *Trace-stream
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # write-slice(*Trace-stream, l2)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Trace-stream/disp32               # push *Trace-stream
+    # . . call
+    e8/call  write-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # write(*Trace-stream, s3)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x10/disp8      .                 # push *(EBP+16)
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Trace-stream/disp32               # push *Trace-stream
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # write(*Trace-stream, s4)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x14/disp8      .                 # push *(EBP+20)
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Trace-stream/disp32               # push *Trace-stream
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # trace(s5)  # implicitly adds a newline and finalizes the trace line
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x18/disp8      .                 # push *(EBP+24)
+    # . . call
+    e8/call  trace/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+$trace-slsss:end:
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-trace-slsss:
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . *Trace-stream->write = 0
+    8b/copy                         0/mod/indirect  5/rm32/.disp32            .             .           0/r32/EAX   Trace-stream/disp32               # copy *Trace-stream to EAX
+    c7          0/subop/copy        0/mod/direct    0/rm32/EAX    .           .             .           .           .               0/imm32           # clear *EAX
+    # (EAX..ECX) = "b"
+    b8/copy-to-EAX  "b"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
+    05/add-to-EAX  4/imm32
+    # var b/EBX : (address slice) = {EAX, ECX}
+    51/push-ECX
+    50/push-EAX
+    89/copy                         3/mod/direct    3/rm32/EBX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBX
+    # trace-slsss("A" b "c" "d" "e")
+    # . . push args
+    68/push  "e"/imm32
+    68/push  "d"/imm32
+    68/push  "c"/imm32
+    53/push-EBX
+    68/push  "A"/imm32
+    # . . call
+    e8/call  trace-slsss/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x14/imm32        # add to ESP
+#?     # dump *Trace-stream {{{
+#?     # . write(2/stderr, "^")
+#?     # . . push args
+#?     68/push  "^"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write-stream(2/stderr, *Trace-stream)
+#?     # . . push args
+#?     ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Trace-stream/disp32               # push *Trace-stream
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # check-trace-contains("Abcde")
+    # . . push args
+    68/push  "F - test-trace-slsss"/imm32
+    68/push  "Abcde"/imm32
+    # . . call
+    e8/call  check-trace-contains/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+num-bytes:  # line : (address stream) -> EAX : int
+    # pseudocode:
+    #   result = 0
+    #   while true
+    #     var word-slice = next-word(line)
+    #     if slice-empty?(word-slice)             # end of line
+    #       break
+    #     if slice-starts-with?(word-slice, "#")  # comment
+    #       break
+    #     if is-label?(word-slice)                # no need for label declarations anymore
+    #       break
+    #     if slice-equal?(word-slice, "==")
+    #       break                                 # no need for segment header lines
+    #     result += compute-width(word-slice)
+    #   return result
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    51/push-ECX
+    52/push-EDX
+    53/push-EBX
+    # var result/EAX = 0
+    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
+    # var word-slice/ECX = {0, 0}
+    68/push  0/imm32/end
+    68/push  0/imm32/start
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+#?     # dump line {{{
+#?     # . write(2/stderr, "LL: ")
+#?     # . . push args
+#?     68/push  "LL: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # write-stream(2/stderr, line)
+#?     # . . push args
+#?     ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+    # . rewind-stream(line)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  rewind-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+$num-bytes:loop:
+    # next-word(line, word-slice)
+    # . . push args
+    51/push-ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  next-word/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # dump word-slice {{{
+#?     # . write(2/stderr, "AA: ")
+#?     # . . push args
+#?     68/push  "AA: "/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . clear-stream(Stderr+4)
+#?     # . . save EAX
+#?     50/push-EAX
+#?     # . . push args
+#?     b8/copy-to-EAX  Stderr/imm32
+#?     05/add-to-EAX  4/imm32
+#?     50/push-EAX
+#?     # . . call
+#?     e8/call  clear-stream/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . . restore EAX
+#?     58/pop-to-EAX
+#?     # . write-slice-buffered(Stderr, word-slice)
+#?     # . . push args
+#?     51/push-ECX
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  write-slice-buffered/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # . flush(Stderr)
+#?     # . . push args
+#?     68/push  Stderr/imm32
+#?     # . . call
+#?     e8/call  flush/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+#?     # . write(2/stderr, "$\n")
+#?     # . . push args
+#?     68/push  "$\n"/imm32
+#?     68/push  2/imm32/stderr
+#?     # . . call
+#?     e8/call  write/disp32
+#?     # . . discard args
+#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+#?     # }}}
+$num-bytes:check0:
+    # if (slice-empty?(word-slice)) break
+    # . save result
+    50/push-EAX
+    # . EAX = slice-empty?(word-slice)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  slice-empty?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . if (EAX != 0) break
+    3d/compare-EAX-and  0/imm32
+    # . restore result now that ZF is set
+    58/pop-to-EAX
+    75/jump-if-not-equal  $num-bytes:end/disp8
+$num-bytes:check-for-comment:
+    # if (slice-starts-with?(word-slice, "#")) break
+    # . start/EDX = word-slice->start
+    8b/copy                         0/mod/indirect  1/rm32/ECX    .           .             .           2/r32/EDX   .               .                 # copy *ECX to EDX
+    # . c/EBX = *start
+    31/xor                          3/mod/direct    3/rm32/EBX    .           .             .           3/r32/EBX   .               .                 # clear EBX
+    8a/copy-byte                    0/mod/indirect  2/rm32/EDX    .           .             .           3/r32/BL    .               .                 # copy byte at *EDX to BL
+    # . if (EBX == '#') break
+    81          7/subop/compare     3/mod/direct    3/rm32/EBX    .           .             .           .           .               0x23/imm32/hash   # compare EBX
+    74/jump-if-equal  $num-bytes:end/disp8
+$num-bytes:check-for-label:
+    # if (slice-ends-with?(word-slice, ":")) break
+    # . end/EDX = word-slice->end
+    8b/copy                         1/mod/*+disp8   1/rm32/ECX    .           .             .           2/r32/EDX   4/disp8         .                 # copy *(ECX+4) to EDX
+    # . c/EBX = *(end-1)
+    31/xor                          3/mod/direct    3/rm32/EBX    .           .             .           3/r32/EBX   .               .                 # clear EBX
+    8a/copy-byte                    1/mod/*+disp8   2/rm32/EDX    .           .             .           3/r32/BL    -1/disp8        .                 # copy byte at *ECX to BL
+    # . if (EBX == ':') break
+    81          7/subop/compare     3/mod/direct    3/rm32/EBX    .           .             .           .           .               0x3a/imm32/colon  # compare EBX
+    74/jump-if-equal  $num-bytes:end/disp8
+$num-bytes:check-for-segment-header:
+    # if (slice-equal?(word-slice, "==")) break
+    # . push result
+    50/push-EAX
+    # . EAX = slice-equal?(word-slice, "==")
+    # . . push args
+    68/push  "=="/imm32
+    51/push-ECX
+    # . . call
+    e8/call  slice-equal?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX != 0) break
+    3d/compare-EAX-and  0/imm32
+    # . restore result now that ZF is set
+    58/pop-to-EAX
+    75/jump-if-not-equal  $num-bytes:end/disp8
+$num-bytes:loop-body:
+    # result += compute-width-of-slice(word-slice)
+    # . copy result to EDX
+    89/copy                         3/mod/direct    2/rm32/EDX    .           .             .           0/r32/EAX   .               .                 # copy EAX to EDX
+    # . EAX = compute-width-of-slice(word-slice)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call compute-width-of-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . EAX += result
+    01/add                          3/mod/direct    0/rm32/EAX    .           .             .           2/r32/EDX   .               .                 # add EDX to EAX
+    e9/jump  $num-bytes:loop/disp32
+$num-bytes:end:
+    # . rewind-stream(line)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  rewind-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . reclaim locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . restore registers
+    5b/pop-to-EBX
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-num-bytes-handles-empty-string:
+    # if a line starts with '#', return 0
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # no contents in input
+    # EAX = num-bytes(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  num-bytes/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-ints-equal(EAX, 0, msg)
+    # . . push args
+    68/push  "F - test-num-bytes-handles-empty-string"/imm32
+    68/push  0/imm32/true
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-num-bytes-ignores-comments:
+    # if a line starts with '#', return 0
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "# abcd")
+    # . . push args
+    68/push  "# abcd"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # EAX = num-bytes(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  num-bytes/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-ints-equal(EAX, 0, msg)
+    # . . push args
+    68/push  "F - test-num-bytes-ignores-comments"/imm32
+    68/push  0/imm32/true
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-num-bytes-ignores-labels:
+    # if the first word ends with ':', return 0
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "ab: # cd")
+    # . . push args
+    68/push  "ab: # cd"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # EAX = num-bytes(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  num-bytes/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-ints-equal(EAX, 0, msg)
+    # . . push args
+    68/push  "F - test-num-bytes-ignores-labels"/imm32
+    68/push  0/imm32/true
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-num-bytes-ignores-segment-headers:
+    # if the first word is '==', return 0
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "== ab cd")
+    # . . push args
+    68/push  "== ab cd"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # EAX = num-bytes(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  num-bytes/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-ints-equal(EAX, 0, msg)
+    # . . push args
+    68/push  "F - test-num-bytes-ignores-segment-headers"/imm32
+    68/push  0/imm32/true
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-num-bytes-counts-words-by-default:
+    # without metadata, count words
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "ab cd ef")
+    # . . push args
+    68/push  "ab cd ef"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # EAX = num-bytes(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  num-bytes/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-ints-equal(EAX, 3, msg)
+    # . . push args
+    68/push  "F - test-num-bytes-counts-words-by-default"/imm32
+    68/push  3/imm32/true
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-num-bytes-ignores-trailing-comment:
+    # trailing comments appropriately ignored
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "ab cd # ef")
+    # . . push args
+    68/push  "ab cd # ef"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # EAX = num-bytes(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  num-bytes/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-ints-equal(EAX, 2, msg)
+    # . . push args
+    68/push  "F - test-num-bytes-ignores-trailing-comment"/imm32
+    68/push  2/imm32/true
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+test-num-bytes-handles-imm32:
+    # if a word has the /imm32 metadata, count it as 4 bytes
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # setup
+    # . clear-stream(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . clear-stream(_test-output-stream)
+    # . . push args
+    68/push  _test-output-stream/imm32
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # initialize input
+    # . write(_test-input-stream, "ab cd/imm32 ef")
+    # . . push args
+    68/push  "ab cd/imm32 ef"/imm32
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # EAX = num-bytes(_test-input-stream)
+    # . . push args
+    68/push  _test-input-stream/imm32
+    # . . call
+    e8/call  num-bytes/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # check-ints-equal(EAX, 6, msg)
+    # . . push args
+    68/push  "F - test-num-bytes-handles-imm32"/imm32
+    68/push  6/imm32/true
+    50/push-EAX
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+== data
+
+# This block of bytes gets copied to the start of the output ELF file, with
+# some fields filled in.
+# http://www.sco.com/developers/gabi/latest/ch4.eheader.html
+Elf_header:
+  # - length
+  0x34/imm32
+  # - data
+$e_ident:
+  7f 45/E 4c/L 46/F
+  01/32-bit  01/little-endian  01/file-version  00/no-os-extensions
+  00 00 00 00 00 00 00 00  # 8 bytes of padding
+$e_type:
+  02 00
+$e_machine:
+  03 00
+$e_version:
+  1/imm32
+Elf_e_entry:
+  0x09000000/imm32  # approximate default; must be updated
+$e_phoff:
+  0x34/imm32  # offset for the 'program header table' containing segment headers
+$e_shoff:
+  0/imm32  # no sections
+$e_flags:
+  0/imm32  # unused
+$e_ehsize:
+  0x34 00
+$e_phentsize:
+  0x20 00
+Elf_e_phnum:
+  00 00  # number of segments; must be updated
+$e_shentsize:
+  00 00  # no sections
+$e_shnum:
+  00 00
+$e_shstrndx:
+  00 00
+
+# This block of bytes gets copied after the Elf_header once for each segment.
+# Some fields need filling in each time.
+# https://docs.oracle.com/cd/E19683-01/816-1386/chapter6-83432/index.html
+Elf_program_header_entry:
+  # - length
+  0x20/imm32
+  # - data
+$p_type:
+  1/imm32/PT_LOAD
+Elf_p_offset:
+  0/imm32  # byte offset in the file at which a segment begins; must be updated
+Elf_p_vaddr:
+  0/imm32  # starting address to store the segment at before running the program
+Elf_p_paddr:
+  0/imm32  # should have same value as Elf_p_vaddr
+Elf_p_filesz:
+  0/imm32
+Elf_p_memsz:
+  0/imm32  # should have same value as Elf_p_filesz
+Elf_p_flags:
+  6/imm32/rw-  # read/write/execute permissions for the segment; must be updated for the code segment
+$p_align:
+  # we hold this constant; changing it will require adjusting the way we
+  # compute the starting address for each segment
+  0x1000/imm32
+
+# . . vim:nowrap:textwidth=0
diff --git a/apps/tests b/apps/tests
new file mode 100755
index 00000000..52af8441
--- /dev/null
+++ b/apps/tests
Binary files differdiff --git a/apps/tests.subx b/apps/tests.subx
new file mode 100644
index 00000000..12f4902b
--- /dev/null
+++ b/apps/tests.subx
@@ -0,0 +1,279 @@
+# Generate code for a new function called 'run-tests' which calls in sequence
+# all functions starting with 'test-'.
+
+== code
+#   instruction                     effective address                                                   register    displacement    immediate
+# . op          subop               mod             rm32          base        index         scale       r32
+# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes
+
+Entry:
+    # Heap = new-segment(Heap-size)
+    # . . push args
+    68/push  Heap/imm32
+    68/push  Heap-size/imm32
+    # . . call
+    e8/call  new-segment/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # initialize-trace-stream(256KB)
+    # . . push args
+    68/push  0x40000/imm32/256KB
+    # . . call
+    e8/call  initialize-trace-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+
+    # run tests if necessary, convert stdin if not
+    # . prolog
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # initialize heap
+    # - if argc > 1 and argv[1] == "test", then return run_tests()
+    # . argc > 1
+    81          7/subop/compare     1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0/disp8         1/imm32           # compare *EBP
+    7e/jump-if-lesser-or-equal  $run-main/disp8
+    # . argv[1] == "test"
+    # . . push args
+    68/push  "test"/imm32
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  kernel-string-equal?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . check result
+    3d/compare-EAX-and  1/imm32
+    75/jump-if-not-equal  $run-main/disp8
+    # . run-tests()
+    e8/call  run-tests/disp32
+    8b/copy                         0/mod/indirect  5/rm32/.disp32            .             .           3/r32/EBX   Num-test-failures/disp32          # copy *Num-test-failures to EBX
+    eb/jump  $main:end/disp8
+$run-main:
+    # - otherwise convert stdin
+    # convert(Stdin, Stdout)
+    # . . push args
+    68/push  Stdout/imm32
+    68/push  Stdin/imm32
+    # . . call
+    e8/call  convert/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . syscall(exit, 0)
+    bb/copy-to-EBX  0/imm32
+$main:end:
+    b8/copy-to-EAX  1/imm32/exit
+    cd/syscall  0x80/imm8
+
+convert:  # in : (address buffered-file), out : (address buffered-file) -> <void>
+    # pseudocode
+    #   bool tests-found = false
+    #   var line = new-stream(512, 1)
+    #   var new-code-segment = new-stream(Segment-size, 1)
+    #   write(new-code-segment, "\n==code\n")
+    #   write(new-code-segment, "run-tests:\n")
+    #   while true
+    #     clear-stream(line)
+    #     read-line-buffered(in, line)
+    #     if (line->write == 0) break               # end of file
+    #     var word-slice = next-word(line)
+    #     if is-label?(word-slice)
+    #       if slice-starts-with?(word-slice, "test-")
+    #         tests-found = true
+    #         write(new-code-segment, "  e8/call  ")
+    #         write-slice(new-code-segment, word-slice)
+    #         write(new-code-segment, "/disp32\n")
+    #     rewind-stream(line)
+    #     write-stream-data(out, line)
+    #   if tests-found
+    #     write(new-code-segment, "  c3/return\n")
+    #     write-stream-data(out, new-code-segment)
+    #   flush(out)
+    #
+    # . prolog
+    55/push-EBP
+    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+    # . save registers
+    50/push-EAX
+    51/push-ECX
+    52/push-EDX
+    53/push-EBX
+    57/push-EDI
+    # var line/ECX : (address stream byte) = stream(512)
+    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x200/imm32       # subtract from ESP
+    68/push  0x200/imm32/length
+    68/push  0/imm32/read
+    68/push  0/imm32/write
+    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
+    # var word-slice/EDX = {0, 0}
+    68/push  0/imm32/end
+    68/push  0/imm32/start
+    89/copy                         3/mod/direct    2/rm32/EDX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EDX
+    # tests-found?/EBX = false
+    31/xor                          3/mod/direct    3/rm32/EBX    .           .             .           3/r32/EBX   .               .                 # clear EBX
+    # new-code-segment/EDI = new-stream(Heap, Segment-size, 1)
+    # . EAX = new-stream(Heap, Segment-size, 1)
+    # . . push args
+    68/push  1/imm32
+    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Segment-size/disp32               # push *Segment-size
+    68/push  Heap/imm32
+    # . . call
+    e8/call  new-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+    # . EDI = EAX
+    89/copy                         3/mod/direct    7/rm32/EDI    .           .             .           0/r32/EAX   .               .                 # copy EAX to EDI
+    # write(new-code-segment, "\n== code\n")
+    # . . push args
+    68/push  "\n== code\n"/imm32
+    57/push-EDI
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # write(new-code-segment, "run-tests:\n")
+    # . . push args
+    68/push  "run-tests:\n"/imm32
+    57/push-EDI
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+$convert:loop:
+    # clear-stream(line)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  clear-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # read-line-buffered(in, line)
+    # . . push args
+    51/push-ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+    # . . call
+    e8/call  read-line-buffered/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+$convert:check0:
+    # if (line->write == 0) break
+    81          7/subop/compare     0/mod/indirect  1/rm32/ECX    .           .             .           .           .               0/imm32           # compare *ECX
+    0f 84/jump-if-equal  $convert:break/disp32
+    # next-word(line, word-slice)
+    # . . push args
+    52/push-EDX
+    51/push-ECX
+    # . . call
+    e8/call  next-word/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+$convert:check-for-label:
+    # if (!is-label?(word-slice)) continue
+    # . EAX = is-label?(word-slice)
+    # . . push args
+    52/push-EDX
+    # . . call
+    e8/call  is-label?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . if (EAX == 0) continue
+    3d/compare-EAX-and  0/imm32
+    74/jump-if-equal  $convert:continue/disp8
+$convert:check-label-prefix:
+    # strip trailing ':' from word-slice
+    ff          1/subop/decrement   1/mod/*+disp8   2/rm32/EDX    .           .             .           .           4/disp8         .                 # decrement *(EDX+4)
+    # if !slice-starts-with?(word-slice, "test-") continue
+    # . . push args
+    68/push  "test-"/imm32
+    52/push-EDX
+    # . . call
+    e8/call  slice-starts-with?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # . if (EAX == 0) break
+    3d/compare-EAX-and  0/imm32
+    74/jump-if-equal  $convert:continue/disp8
+$convert:call-test-function:
+    # tests-found? = true
+    bb/copy-to-EBX  1/imm32/true
+    # write(new-code-segment, "  e8/call  ")
+    # . . push args
+    68/push  "  e8/call  "/imm32
+    57/push-EDI
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # write-slice(new-code-segment, word-slice)
+    # . . push args
+    52/push-EDX
+    57/push-EDI
+    # . . call
+    e8/call  write-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # write(new-code-segment, "/disp32\n")
+    # . . push args
+    68/push  "/disp32\n"/imm32
+    57/push-EDI
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+$convert:continue:
+    # rewind-stream(line)
+    # . . push args
+    51/push-ECX
+    # . . call
+    e8/call  rewind-stream/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # write-stream-data(out, line)
+    # . . push args
+    51/push-ECX
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write-stream-data/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # loop
+    e9/jump  $convert:loop/disp32
+$convert:break:
+    # if (!tests-found?) goto end
+    81          7/subop/compare     3/mod/direct    3/rm32/EBX    .           .             .           .           .               0/imm32           # compare EBX
+    74/jump-if-equal  $convert:end/disp8
+    # write(new-code-segment, "  c3/return\n")
+    # . . push args
+    68/push  "  c3/return\n"/imm32
+    57/push-EDI
+    # . . call
+    e8/call  write/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+    # write-stream-data(out, new-code-segment)
+    # . . push args
+    57/push-EDI
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  write-stream-data/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+$convert:end:
+    # flush(out)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+    # . . call
+    e8/call  flush/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+    # . reclaim locals
+    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x214/imm32       # add to ESP
+    # . restore registers
+    5f/pop-to-EDI
+    5b/pop-to-EBX
+    5a/pop-to-EDX
+    59/pop-to-ECX
+    58/pop-to-EAX
+    # . epilog
+    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+    5d/pop-to-EBP
+    c3/return
+
+# . . vim:nowrap:textwidth=0