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# Assign addresses (co-ordinates) to instructions (landmarks) in a program
# (landscape).
#
# To build:
#   $ bootstrap/bootstrap translate [01]*.subx subx-params.subx survey_baremetal.subx  -o survey_baremetal
#
# The expected input is a stream of bytes and some interspersed labels.
# Comments and '==' segment headers are allowed, but names are ignored. The
# emitted code will all lie in a single contiguous address range starting at
# address 0x7c00. Addresses in segment headers are optional. If provided, this
# program will insert padding in the output until the desired address is
# reached.
#
#   $ cat x
#   == code
#   l1:
#   aa bb l1/imm8
#   cc dd l2/disp32
#   l2:
#   ee foo/imm32
#   == data 0x7c10
#   foo:
#     34
#
# The output is a list of labels and their computed addresses.
#
#   $ cat x  |bootstrap/bootstrap run survey_baremetal
#   0x7c00 l1
#   0x7c09 l2
#   0x7c10 foo

== 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

    # 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(Trace-size)
    # . . push args
    ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           Trace-size/disp32                 # push *Heap-size
    # . . call
    e8/call  initialize-trace-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/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-survey-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-survey-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-survey-main:end/disp8
$subx-survey-main:interactive:
    # - otherwise convert stdin
    # subx-survey(Stdin, Stdout)
    # . . push args
    68/push  Stdout/imm32
    68/push  Stdin/imm32
    # . . call
    e8/call  subx-survey/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
$subx-survey-main:end:
    e8/call  syscall_exit/disp32

subx-survey:  # infile: (addr buffered-file), out: (addr buffered-file)
    # pseudocode
    #   var in: (stream byte Input-size)
    #   slurp(infile, in)
    #   var labels: (stream {label-name, address} Max-labels)
    #   compute-addresses(in, labels)
    #   emit-labels(out, labels)
    #
    # . prologue
    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 labels/edx: (stream {label-name, address} Max-labels)
    # (we get more rows than Max-labels advertises because row size is smaller than in survey_elf)
    # . data
    2b/subtract                     0/mod/indirect  5/rm32/.disp32            .             .           4/r32/esp   Max-labels/disp32                 # subtract *Max-labels from esp
    # . size
    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 byte Input-size)
    # . data
    2b/subtract                     0/mod/indirect  5/rm32/.disp32            .             .           4/r32/esp   Input-size/disp32                 # subtract *Input-size from esp
    # . size
    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
    # 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
    # compute-addresses(in, labels)
    # . . push args
    52/push-edx
    56/push-esi
    # . . call
    e8/call  compute-addresses/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # emit-labels(out, labels)
    # . . push args
    52/push-edx
    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           0xc/disp8       .                 # push *(ebp+12)
    # . . call
    e8/call  emit-labels/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
$subx-survey:end:
    # . reclaim locals
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0x18/imm32        # add to esp
    03/add                          0/mod/indirect  5/rm32/.disp32            .             .           4/r32/esp   Max-labels/disp32                 # add *Max-labels to esp
    03/add                          0/mod/indirect  5/rm32/.disp32            .             .           4/r32/esp   Input-size/disp32                 # add *Input-size to esp
    # . restore registers
    5e/pop-to-esi
    5a/pop-to-edx
    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-subx-survey-computes-addresses:
    # input:
    #   == code
    #   ab x/imm32
    #   == data
    #   x:
    #     01
    #
    # trace contains (in any order):
    #   label x is at address 0x7c05
    #
    # . prologue
    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->buffer)
    # . . push args
    68/push  $_test-input-buffered-file->buffer/imm32
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # . clear-stream(_test-output-stream)
    # . . push args
    68/push  _test-output-stream/imm32
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # . clear-stream($_test-output-buffered-file->buffer)
    # . . push args
    68/push  $_test-output-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 input
    # . 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, "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\n")
    # . . push args
    68/push  "== data\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
    # subx-survey(_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  subx-survey/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 0x00007c05.", msg)
    # . . push args
    68/push  "F - test-subx-survey-computes-addresses/0"/imm32
    68/push  "label 'x' is at address 0x00007c05."/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
    # . epilogue
    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
    5d/pop-to-ebp
    c3/return

test-subx-survey-computes-addresses-with-padding:
    # input:
    #   == code
    #   ab x/imm32
    #   == data 0x7c10
    #   x:
    #     01
    #
    # trace contains (in any order):
    #   label x is at address 0x7c10
    #
    # . prologue
    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->buffer)
    # . . push args
    68/push  $_test-input-buffered-file->buffer/imm32
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # . clear-stream(_test-output-stream)
    # . . push args
    68/push  _test-output-stream/imm32
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # . clear-stream($_test-output-buffered-file->buffer)
    # . . push args
    68/push  $_test-output-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 input
    # . 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, "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\n")
    # . . push args
    68/push  "== data 0x7c10\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
    # subx-survey(_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  subx-survey/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 0x00007c10.", msg)
    # . . push args
    68/push  "F - test-subx-survey-computes-addresses-with-padding/0"/imm32
    68/push  "label 'x' is at address 0x00007c10."/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
    # . epilogue
    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
    5d/pop-to-ebp
    c3/return

compute-addresses:  # in: (addr stream byte), labels: (addr stream {(handle array byte), address})
    # pseudocode:
    #   var current-address = 0x7c00
    #   var line: (stream byte 512)
    #   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, "==")  # segment header
    #         word-slice = next-word(line)
    #         if slice-empty?(word-slice)
    #           abort
    #         word-slice = next-word(line)  # segment address
    #         if slice-empty?(word-slice)
    #           goto line-loop              # segment address is optional
    #         new-address = parse-hex-int-from-slice(word-slice)
    #         if new-address < current-address
    #           abort
    #         current-address = new-address
    #       else if label?(word-slice)
    #         strip trailing ':' from word-slice
    #         trace("label '" word-slice "' is at address " current-address ".")
    #         # labels occupy no space, so no need to increment offsets
    #       else
    #         width = compute-width-of-slice(word-slice)
    #         current-address += width
    #
    # . prologue
    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 current-address/esi: int = 0x7c00
    be/copy-to-esi  0x7c00/imm32
    # var line/ecx: (stream byte 512)
    81          5/subop/subtract    3/mod/direct    4/rm32/esp    .           .             .           .           .               0x200/imm32       # subtract from esp
    68/push  0x200/imm32/size
    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: (addr slice)
    68/push  0/imm32
    68/push  0/imm32
    89/copy                         3/mod/direct    2/rm32/edx    .           .             .           4/r32/esp   .               .                 # copy esp to edx
$compute-addresses: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
    # 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-=  $compute-addresses:end/disp32
#?     # dump line {{{
#?     # . write(2/stderr, "LL: ")
#?     # . . push args
#?     68/push  "LL: "/imm32
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # write-stream(2/stderr, line)
#?     # . . push args
#?     51/push-ecx
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write-stream/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # . write(2/stderr, "$\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-addresses: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
$compute-addresses:case-empty:
    # 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 != false) break
    3d/compare-eax-and  0/imm32/false
    0f 85/jump-if-!=  $compute-addresses:line-loop/disp32
$compute-addresses:case-comment:
    # if slice-starts-with?(word-slice, "#") break
    # . . push args
    68/push  "#"/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 != false) break
    3d/compare-eax-and  0/imm32/false
    0f 85/jump-if-!=  $compute-addresses:line-loop/disp32
$compute-addresses:case-segment-header:
    # if !slice-equal?(word-slice, "==") goto next case
    # . 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 != false) break
    3d/compare-eax-and  0/imm32/false
    0f 84/jump-if-=  $compute-addresses:case-label/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
    # if slice-empty?(word-slice) abort
    # . 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 != false) abort
    3d/compare-eax-and  0/imm32/false
    0f 85/jump-if-!=  $compute-addresses:abort/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
    # 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 != false) break
    3d/compare-eax-and  0/imm32/false
    0f 85/jump-if-!=  $compute-addresses:line-loop/disp32
    # var new-address/eax: int = parse-hex-int-from-slice(word-slice)
    # . . push args
    52/push-edx
    # . . call
    e8/call  parse-hex-int-from-slice/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # if (new-address < current-address) abort
    39/compare                      3/mod/direct    0/rm32/eax    .           .             .           6/r32/esi   .               .                 # compare eax with esi
    0f 82/jump-if-addr<  $compute-addresses:error-bad-segment-address/disp32
    # current-address = new-address
    89/copy                         3/mod/direct    6/rm32/esi    .           .             .           0/r32/eax   .               .                 # copy eax to esi
    # break
    e9/jump  $compute-addresses:line-loop/disp32
$compute-addresses:case-label:
    # if (!label?(word-slice)) goto next case
    # . eax = label?(word-slice)
    # . . push args
    52/push-edx
    # . . call
    e8/call  label?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # . if (eax == false) goto next case
    3d/compare-eax-and  0/imm32/false
    0f 84/jump-if-=  $compute-addresses:case-default/disp32
    # strip trailing ':' from word-slice
    ff          1/subop/decrement   1/mod/*+disp8   2/rm32/edx    .           .             .           .           4/disp8         .                 # decrement *(edx+4)
    # var tmp/eax: (addr int) = get-or-insert-slice(labels, word-slice, row-size=12)
    # . . push args
    68/push  Heap/imm32
    68/push  0xc/imm32/row-size
    52/push-edx
    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           0xc/disp8       .                 # push *(ebp+12)
    # . . call
    e8/call  get-or-insert-slice/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0x10/imm32        # add to esp
    # *tmp = current-address
    89/copy                         0/mod/indirect  0/rm32/eax    .           .             .           6/r32/esi   .               .                 # copy esi to *eax
    # trace-slsns("label '" word-slice "' is at address " current-address ".")
    # . . push args
    68/push  "."/imm32
    56/push-esi
    68/push  "' is at address "/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-addresses:word-loop/disp32
$compute-addresses:case-default:
    # width/eax = compute-width-of-slice(word-slice)
    # . . push args
    52/push-edx
    # . . call
    e8/call compute-width-of-slice/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # current-address += width
    01/add                          3/mod/direct    6/rm32/esi    .           .             .           0/r32/eax   .               .                 # add eax to *esi
#?     # dump segment-offset {{{
#?     # . write(2/stderr, "segment-offset: ")
#?     # . . push args
#?     68/push  "segment-offset: "/imm32
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # . clear-stream($Stderr->buffer)
#?     # . . push args
#?     68/push  $Stderr->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
#?     # . write-int32-hex-buffered(Stderr, segment-offset)
#?     # . . push args
#?     52/push-edx
#?     ff          6/subop/push        0/mod/indirect  5/rm32/.disp32            .             .           .           compute-addresses:segment-offset/disp32  # push *segment-offset
#?     68/push  Stderr/imm32
#?     # . . call
#?     e8/call  write-int32-hex-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  Newline/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-addresses:word-loop/disp32
$compute-addresses: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
    # . epilogue
    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
    5d/pop-to-ebp
    c3/return

$compute-addresses:abort:
    # . _write(2/stderr, error)
    # . . push args
    68/push  "'==' must be followed by segment name and optionally an address\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
    e8/call  syscall_exit/disp32
    # never gets here

$compute-addresses:error-bad-segment-address:
    # . _write(2/stderr, error)
    # . . push args
    68/push  "'==' specifies an address that implies negative padding\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
    e8/call  syscall_exit/disp32
    # never gets here

test-compute-addresses:
    # input:
    #   == code
    #   ab x/imm32  # skip comment
    #   == data
    #   00
    #   x:
    #     34
    #
    # trace contains (in any order):
    #   label 'x' is at address 0x7c06.
    #
    # . prologue
    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 labels/edx: (stream byte 2*12)
    81          5/subop/subtract    3/mod/direct    4/rm32/esp    .           .             .           .           .               0x18/imm32        # subtract from esp
    68/push  0x18/imm32/size
    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\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, "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\n")
    # . . push args
    68/push  "== data\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-addresses(_test-input-stream, labels)
    # . . push args
    52/push-edx
    68/push  _test-input-stream/imm32
    # . . call
    e8/call  compute-addresses/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
#?     # }}}
    # . check-trace-contains("label 'x' is at address 0x00007c06.", msg)
    # . . push args
    68/push  "F - test-compute-addresses"/imm32
    68/push  "label 'x' is at address 0x00007c06."/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, 0xc, msg)
    # . . push args
    68/push  "F - test-compute-addresses-maintains-labels-write-index"/imm32
    68/push  0xc/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
    # . reclaim locals
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0x24/imm32        # add to esp
    # . epilogue
    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
    5d/pop-to-ebp
    c3/return

emit-labels:  # out: (addr buffered-file), labels: (addr stream {(handle array byte), address})
    # pseudocode:
    #   curr = table->data
    #   max = &table->data[table->write]
    #   while curr < max
    #     var label: (addr array byte) = lookup(*curr)
    #     curr += 8
    #     write-buffered(out, label)
    #     write-buffered(out, ' ')
    #     write-buffered(out, *curr)
    #     curr += 4
    #     write(out, '\n')
    #   return 0
    #
    # . prologue
    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 = table
    8b/copy                         1/mod/*+disp8   5/rm32/ebp    .           .             .           6/r32/esi   0xc/disp8       .                 # copy *(ebp+12) to esi
    # var curr/ecx: (addr handle array byte) = table->data
    8d/copy-address                 1/mod/*+disp8   6/rm32/esi    .           .             .           1/r32/ecx   0xc/disp8       .                 # copy esi+12 to ecx
    # var max/edx: (addr byte) = &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
$emit-labels:loop:
    # if (curr >= max) return null
    39/compare                      3/mod/direct    1/rm32/ecx    .           .             .           2/r32/edx   .               .                 # compare ecx with edx
    0f 83/jump-if-addr>=  $emit-labels:end/disp32
    # var label/eax: (addr array byte) = lookup(*curr)
    # . . push args
    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  lookup/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # curr += 8
    81          0/subop/add         3/mod/direct    1/rm32/ecx    .           .             .           .           .               8/imm32           # add to ecx
    # write-buffered(out, label)
    # . . push args
    50/push-eax
    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
    # write-buffered(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-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-int32-hex-buffered(out, *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    .           .             .           .           8/disp8         .                 # push *(ebp+8)
    # . . call
    e8/call  write-int32-hex-buffered/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # curr += 4
    81          0/subop/add         3/mod/direct    1/rm32/ecx    .           .             .           .           .               4/imm32           # add to ecx
    # write-buffered(out, '\n')
    # . . push args
    68/push  Newline/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
    # loop
    e9/jump  $emit-labels:loop/disp32
$emit-labels:end:
    # . restore registers
    5e/pop-to-esi
    5a/pop-to-edx
    59/pop-to-ecx
    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

# - some helpers for tests

# 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: (addr array byte)
#   l: (addr slice)
# one gotcha: 's5' must not be empty

trace-slsns:  # s1: (addr array byte), l2: (addr slice), s3: (addr array byte), n4: int, s5: (addr array byte)
    # . prologue
    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-int32-hex(*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  write-int32-hex/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:
    # . epilogue
    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
    5d/pop-to-ebp
    c3/return

test-trace-slsns:
    # . prologue
    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: 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
    # . epilogue
    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