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-rw-r--r--apps/hex.subx1435
1 files changed, 0 insertions, 1435 deletions
diff --git a/apps/hex.subx b/apps/hex.subx
deleted file mode 100644
index 5a86f8ec..00000000
--- a/apps/hex.subx
+++ /dev/null
@@ -1,1435 +0,0 @@
-# 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:
-#   $ ./bootstrap translate init.linux [01]*.subx apps/subx-params.subx apps/hex.subx  -o apps/hex
-#   $ echo '80 81 82  # comment'  |./bootstrap 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
-    # . prologue
-    89/copy                         3/mod/direct    5/rm32/ebp    .           .             .           4/r32/esp   .               .                 # copy esp to ebp
-
-    # 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
-
-    # - if argc > 1 and argv[1] == "test", then return run_tests()
-    # if (argc <= 1) goto interactive
-    81          7/subop/compare     1/mod/*+disp8   5/rm32/ebp    .           .             .           .           0/disp8         1/imm32           # compare *ebp
-    7e/jump-if-<=  $subx-hex-main:interactive/disp8
-    # if (!kernel-string-equal?(argv[1], "test")) goto interactive
-    # . eax = kernel-string-equal?(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
-    # . if (eax == false) goto interactive
-    3d/compare-eax-and  0/imm32/false
-    74/jump-if-=  $subx-hex-main:interactive/disp8
-    # run-tests()
-    e8/call  run-tests/disp32
-    # syscall(exit, *Num-test-failures)
-    8b/copy                         0/mod/indirect  5/rm32/.disp32            .             .           3/r32/ebx   Num-test-failures/disp32          # copy *Num-test-failures to ebx
-    eb/jump  $subx-hex-main:end/disp8
-$subx-hex-main:interactive:
-    # - otherwise convert stdin
-    # . subx-hex(Stdin, Stdout, Stderr, 0)
-    # . . push args
-    68/push  0/imm32/exit-descriptor
-    68/push  Stderr/imm32
-    68/push  Stdout/imm32
-    68/push  Stdin/imm32
-    # . . call
-    e8/call  subx-hex/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
-$subx-hex-main:end:
-    e8/call  syscall_exit/disp32
-
-# the main entry point
-subx-hex:  # in: (addr buffered-file), out: (addr buffered-file), err: (addr buffered-file), ed: (addr exit-descriptor)
-    # pseudocode:
-    #   while true
-    #     eax = convert-next-octet(in, err, ed)
-    #     if (eax == Eof) break
-    #     write-byte-buffered(out, AL)
-    #   flush(out)
-    #
-    # . prologue
-    55/push-ebp
-    89/copy                         3/mod/direct    5/rm32/ebp    .           .             .           4/r32/esp   .               .                 # copy esp to ebp
-    # . save registers
-    50/push-eax
-$subx-hex: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-=  $subx-hex: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  $subx-hex:loop/disp8
-$subx-hex: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
-$subx-hex:end:
-    # . restore registers
-    58/pop-to-eax
-    # . epilogue
-    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: (addr buffered-file), err: (addr buffered-file), ed: (addr 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
-    #
-    # . prologue
-    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-=  $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-!=  $convert-next-octet:convert/disp8
-    # . error-byte(ed, err, msg, '.')  # reusing error-byte to avoid creating _yet_ another helper
-    # . . push args
-    68/push  0x2e/imm32/period/dummy
-    68/push  "convert-next-octet: partial byte found"/imm32
-    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           0xc/disp8       .                 # push *(ebp+12)
-    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           0x10/disp8      .                 # push *(ebp+16)
-    # . . call
-    e8/call  error-byte/disp32  # never returns
-$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
-$convert-next-octet:end:
-    # . restore registers
-    59/pop-to-ecx
-    # . epilogue
-    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
-    5d/pop-to-ebp
-    c3/return
-
-test-convert-next-octet:
-    # - check that the first two bytes of the input are assembled into the resulting octet
-    # This test uses exit-descriptors. Use ebp for setting up local variables.
-    55/push-ebp
-    89/copy                         3/mod/direct    5/rm32/ebp    .           .             .           4/r32/esp   .               .                 # copy esp to ebp
-    # clear all streams
-    # . clear-stream(_test-stream)
-    # . . push args
-    68/push  _test-stream/imm32
-    # . . call
-    e8/call  clear-stream/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
-    # . clear-stream($_test-buffered-file->buffer)
-    # . . push args
-    68/push  $_test-buffered-file->buffer/imm32
-    # . . call
-    e8/call  clear-stream/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
-    # . clear-stream(_test-error-stream)
-    # . . push args
-    68/push  _test-error-stream/imm32
-    # . . call
-    e8/call  clear-stream/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
-    # . clear-stream($_test-error-buffered-file->buffer)
-    # . . push args
-    68/push  $_test-error-buffered-file->buffer/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 '_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-!=  $test-convert-next-octet:end/disp8
-    # check-ints-equal(eax, 0xab, msg)
-    # . . push args
-    68/push  "F - test-convert-next-octet"/imm32
-    68/push  0xab/imm32/ab
-    50/push-eax
-    # . . call
-    e8/call  check-ints-equal/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
-$test-convert-next-octet:end:
-    # . epilogue
-    # 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->buffer)
-    # . . push args
-    68/push  $_test-buffered-file->buffer/imm32
-    # . . call
-    e8/call  clear-stream/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
-    # . clear-stream(_test-error-stream)
-    # . . push args
-    68/push  _test-error-stream/imm32
-    # . . call
-    e8/call  clear-stream/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
-    # . clear-stream($_test-error-buffered-file->buffer)
-    # . . push args
-    68/push  $_test-error-buffered-file->buffer/imm32
-    # . . 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-!=  $test-convert-next-octet-handles-Eof:end/disp8
-    # check-ints-equal(eax, Eof, msg)
-    # . . push args
-    68/push  "F - test-convert-next-octet-handles-Eof"/imm32
-    68/push  0xffffffff/imm32/Eof
-    50/push-eax
-    # . . call
-    e8/call  check-ints-equal/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
-$test-convert-next-octet-handles-Eof:end:
-    # . epilogue
-    # 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->buffer)
-    # . . push args
-    68/push  $_test-buffered-file->buffer/imm32
-    # . . call
-    e8/call  clear-stream/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
-    # . clear-stream(_test-error-stream)
-    # . . push args
-    68/push  _test-error-stream/imm32
-    # . . call
-    e8/call  clear-stream/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
-    # . clear-stream($_test-error-buffered-file->buffer)
-    # . . push args
-    68/push  $_test-error-buffered-file->buffer/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 '_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:
-    # . epilogue
-    # 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: (addr buffered-file), err: (addr buffered-file), ed: (addr 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)
-    #
-    # . prologue
-    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-=  $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/false
-    # . restore eax (does not affect flags)
-    58/pop-to-eax
-    # . check whether to return
-    75/jump-if-!=  $scan-next-byte:end/disp8
-$scan-next-byte:check1:
-    # if (eax == ' ') continue
-    3d/compare-eax-and  0x20/imm32/space
-    74/jump-if-=  $scan-next-byte:loop/disp8
-    # if (eax == '\t') continue
-    3d/compare-eax-and  9/imm32/tab
-    74/jump-if-=  $scan-next-byte:loop/disp8
-    # if (eax == '\n') continue
-    3d/compare-eax-and  0xa/imm32/newline
-    74/jump-if-=  $scan-next-byte:loop/disp8
-$scan-next-byte:check2:
-    # if (eax == '#') skip-until-newline(in)
-    3d/compare-with-eax  0x23/imm32/hash
-    75/jump-if-!=  $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
-$scan-next-byte:end:
-    # . restore registers
-    # . epilogue
-    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
-    5d/pop-to-ebp
-    c3/return
-
-test-scan-next-byte:
-    # - check that the first byte of the input is returned
-    # This test uses exit-descriptors. Use ebp for setting up local variables.
-    55/push-ebp
-    89/copy                         3/mod/direct    5/rm32/ebp    .           .             .           4/r32/esp   .               .                 # copy esp to ebp
-    # clear all streams
-    # . clear-stream(_test-stream)
-    # . . push args
-    68/push  _test-stream/imm32
-    # . . call
-    e8/call  clear-stream/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
-    # . clear-stream($_test-buffered-file->buffer)
-    # . . push args
-    68/push  $_test-buffered-file->buffer/imm32
-    # . . call
-    e8/call  clear-stream/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
-    # . clear-stream(_test-error-stream)
-    # . . push args
-    68/push  _test-error-stream/imm32
-    # . . call
-    e8/call  clear-stream/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
-    # . clear-stream($_test-error-buffered-file->buffer)
-    # . . push args
-    68/push  $_test-error-buffered-file->buffer/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 '_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-!=  $test-scan-next-byte:end/disp8
-    # check-ints-equal(eax, 0x61/a, msg)
-    # . . push args
-    68/push  "F - test-scan-next-byte"/imm32
-    68/push  0x61/imm32/a
-    50/push-eax
-    # . . call
-    e8/call  check-ints-equal/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
-$test-scan-next-byte:end:
-    # . epilogue
-    # 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->buffer)
-    # . . push args
-    68/push  $_test-buffered-file->buffer/imm32
-    # . . call
-    e8/call  clear-stream/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
-    # . clear-stream(_test-error-stream)
-    # . . push args
-    68/push  _test-error-stream/imm32
-    # . . call
-    e8/call  clear-stream/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
-    # . clear-stream($_test-error-buffered-file->buffer)
-    # . . push args
-    68/push  $_test-error-buffered-file->buffer/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 '_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-!=  $test-scan-next-byte-skips-whitespace:end/disp8
-    # check-ints-equal(eax, 0x61/a, msg)
-    # . . push args
-    68/push  "F - test-scan-next-byte-skips-whitespace"/imm32
-    68/push  0x61/imm32/a
-    50/push-eax
-    # . . call
-    e8/call  check-ints-equal/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
-$test-scan-next-byte-skips-whitespace:end:
-    # . epilogue
-    # 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->buffer)
-    # . . push args
-    68/push  $_test-buffered-file->buffer/imm32
-    # . . call
-    e8/call  clear-stream/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
-    # . clear-stream(_test-error-stream)
-    # . . push args
-    68/push  _test-error-stream/imm32
-    # . . call
-    e8/call  clear-stream/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
-    # . clear-stream($_test-error-buffered-file->buffer)
-    # . . push args
-    68/push  $_test-error-buffered-file->buffer/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 '_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-!=  $test-scan-next-byte-skips-comment:end/disp8
-    # check-ints-equal(eax, 0x61/a, msg)
-    # . . push args
-    68/push  "F - test-scan-next-byte-skips-comment"/imm32
-    68/push  0x61/imm32/a
-    50/push-eax
-    # . . call
-    e8/call  check-ints-equal/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
-$test-scan-next-byte-skips-comment:end:
-    # . epilogue
-    # 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->buffer)
-    # . . push args
-    68/push  $_test-buffered-file->buffer/imm32
-    # . . call
-    e8/call  clear-stream/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
-    # . clear-stream(_test-error-stream)
-    # . . push args
-    68/push  _test-error-stream/imm32
-    # . . call
-    e8/call  clear-stream/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
-    # . clear-stream($_test-error-buffered-file->buffer)
-    # . . push args
-    68/push  $_test-error-buffered-file->buffer/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 '_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-!=  $test-scan-next-byte-skips-comment-and-whitespace:end/disp8
-    # check-ints-equal(eax, 0x61/a, msg)
-    # . . push args
-    68/push  "F - test-scan-next-byte-skips-comment-and-whitespace"/imm32
-    68/push  0x61/imm32/a
-    50/push-eax
-    # . . call
-    e8/call  check-ints-equal/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
-$test-scan-next-byte-skips-comment-and-whitespace:end:
-    # . epilogue
-    # 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($_test-buffered-file->buffer)
-    # . . push args
-    b8/copy-to-eax  _test-buffered-file/imm32
-    05/add-to-eax  4/imm32
-    50/push-eax
-    # . . call
-    e8/call  clear-stream/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
-    # . clear-stream(_test-error-stream)
-    # . . push args
-    68/push  _test-error-stream/imm32
-    # . . call
-    e8/call  clear-stream/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
-    # . clear-stream($_test-error-buffered-file->buffer)
-    # . . push args
-    68/push  $_test-error-buffered-file->buffer/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 '_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-!=  $test-scan-next-byte-skips-whitespace-and-comment:end/disp8
-    # check-ints-equal(eax, 0x61/a, msg)
-    # . . push args
-    68/push  "F - test-scan-next-byte-skips-whitespace-and-comment"/imm32
-    68/push  0x61/imm32/a
-    50/push-eax
-    # . . call
-    e8/call  check-ints-equal/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
-$test-scan-next-byte-skips-whitespace-and-comment:end:
-    # . epilogue
-    # 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->buffer)
-    # . . push args
-    68/push  $_test-buffered-file->buffer/imm32
-    # . . call
-    e8/call  clear-stream/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
-    # . clear-stream(_test-error-stream)
-    # . . push args
-    68/push  _test-error-stream/imm32
-    # . . call
-    e8/call  clear-stream/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
-    # . clear-stream($_test-error-buffered-file->buffer)
-    # . . push args
-    68/push  $_test-error-buffered-file->buffer/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 '_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-!=  $test-scan-next-byte-reads-final-byte:end/disp8
-    # check-ints-equal(eax, 0x61/a, msg)
-    # . . push args
-    68/push  "F - test-scan-next-byte-reads-final-byte"/imm32
-    68/push  0x61/imm32/a
-    50/push-eax
-    # . . call
-    e8/call  check-ints-equal/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
-$test-scan-next-byte-reads-final-byte:end:
-    # . epilogue
-    # 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->buffer)
-    # . . push args
-    68/push  $_test-buffered-file->buffer/imm32
-    # . . call
-    e8/call  clear-stream/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
-    # . clear-stream(_test-error-stream)
-    # . . push args
-    68/push  _test-error-stream/imm32
-    # . . call
-    e8/call  clear-stream/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
-    # . clear-stream($_test-error-buffered-file->buffer)
-    # . . push args
-    68/push  $_test-error-buffered-file->buffer/imm32
-    # . . 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-!=  $test-scan-next-byte-handles-Eof:end/disp8
-    # check-ints-equal(eax, Eof, msg)
-    # . . push args
-    68/push  "F - test-scan-next-byte-handles-Eof"/imm32
-    68/push  0xffffffff/imm32/Eof
-    50/push-eax
-    # . . call
-    e8/call  check-ints-equal/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
-$test-scan-next-byte-handles-Eof:end:
-    # . epilogue
-    # 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->buffer)
-    # . . push args
-    68/push  $_test-buffered-file->buffer/imm32
-    # . . call
-    e8/call  clear-stream/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
-    # . clear-stream(_test-error-stream)
-    # . . push args
-    68/push  _test-error-stream/imm32
-    # . . call
-    e8/call  clear-stream/disp32
-    # . . discard args
-    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
-    # . clear-stream($_test-error-buffered-file->buffer)
-    # . . push args
-    68/push  $_test-error-buffered-file->buffer/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 '_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:
-    # . epilogue
-    # 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: (addr buffered-file)
-    # pseudocode:
-    #   push eax
-    #   while true
-    #     eax = read-byte-buffered(in)
-    #     if (eax == Eof) break
-    #     if (eax == 0x0a) break
-    #   pop eax
-    # . prologue
-    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-=  $skip-until-newline:end/disp8
-    # . if (eax != 0xa/newline) loop
-    3d/compare-eax-and  0xa/imm32/newline
-    75/jump-if-!=  $skip-until-newline:loop/disp8
-$skip-until-newline:end:
-    # . restore registers
-    58/pop-to-eax
-    # . epilogue
-    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->buffer)
-    # . . push args
-    68/push  $_test-buffered-file->buffer/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 '_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
-
-# . . vim:nowrap:textwidth=0