# Assign addresses (co-ordinates) to instructions (landmarks) in a program
# (landscape).
# Read a list of addresses and labels from a file called 'labels',
# then replace labels in stdin with their addresses.
#
# To build:
#   $ bootstrap/bootstrap translate [01]*.subx subx-params.subx labels_baremetal.subx  -o labels_baremetal
#
# Stdin should be 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 the stream of bytes without segment headers or label definitions,
# and with label references replaced with numeric values/displacements.
#
#   $ cat x  |bootstrap/bootstrap run survey_baremetal labels
#   # 0x7c00
#   aa bb nn  # some computed address
#   cc dd nn nn nn nn  # some computed displacement
#   ee nn nn nn nn  # address right after this instruction
#   # 0x7c0e
#   00 00  # padding
#   # 0x7c10
#   34  # data segment interleaved with code

== 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-labels-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-labels-main:interactive/disp8
    # run-tests()
#?     e8/call  test-emit-output-with-padding/disp32
    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-labels-main:end/disp8
$subx-labels-main:interactive:
    # - otherwise convert stdin
    # var labels-file/esi: (addr buffered-file) from syscall_open("labels", READ)
    # . data
    81          5/subop/subtract    3/mod/direct    4/rm32/esp    .           .             .           .           .               0x1000/imm32      # subtract from esp
    # . size
    68/push  0x1000/imm32
    # . read
    68/push  0/imm32/read
    # . write
    68/push  0/imm32/write
    # . fd = syscall_open("labels", READ)
    bb/copy-to-ebx  Label-file/imm32
    b9/copy-to-ecx  0/imm32/read-mode
    ba/copy-to-edx  0x180/imm32/permissions
    e8/call syscall_open/disp32
    50/push-eax
    89/copy                         3/mod/direct    6/rm32/esi    .           .             .           4/r32/esp   .               .                 # copy esp to esi
    # subx-labels(Stdin, label-fd, Stdout)
    # . . push args
    68/push  Stdout/imm32
    56/push-esi
    68/push  Stdin/imm32
    # . . call
    e8/call  subx-labels/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-labels-main:end:
    e8/call  syscall_exit/disp32

== data

Label-file:
  6c/l 61/a 62/b 65/e 6c/l 73/s 00/nul

== code

subx-labels:  # infile: (addr buffered-file), labels-file: (addr buffered-file), out: (addr buffered-file)
    # pseudocode
    #   var labels: (stream {label-name, address} Max-labels)
    #   load-labels(labels-file, labels)
    #   var in: (stream byte Input-size)
    #   slurp(infile, in)
    #   emit-output(in, out, labels)
    #
    # . prologue
    55/push-ebp
    89/copy                         3/mod/direct    5/rm32/ebp    .           .             .           4/r32/esp   .               .                 # copy esp to ebp
    # . save registers
    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
    # load-labels(labels-file, labels)
    # . . push args
    52/push-edx
    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           0xc/disp8       .                 # push *(ebp+12)
    # . . call
    e8/call  load-labels/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # 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
    # emit-output(in, out, labels)
    # . . push args
    52/push-edx
    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           0x10/disp8      .                 # push *(ebp+16)
    56/push-esi
    # . . call
    e8/call  emit-output/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # flush(out)
    # . . push args
    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           0x10/disp8      .                 # push *(ebp+16)
    # . . call
    e8/call  flush/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
$subx-labels: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
    # . epilogue
    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
    5d/pop-to-ebp
    c3/return

load-labels:  # in: (addr buffered-file), labels: (stream {label-name, address} Max-labels)
    # pseudocode
    #   var line: (stream byte 512)
    #   while true
    #     clear-stream(line)
    #     read-line-buffered(in, line)
    #     if (line->write == 0) break               # end of file
    #     var word-slice/ecx: (addr slice) = next-word(line)
    #     var dest/edi: (addr int) = get-or-insert-slice(labels, word-slice, 12 bytes/row)
    #     word-slice = next-word(line)
    #     var address/eax: int = parse-hex-int-from-slice(word-slice)
    #     *dest = address
    #
    # . 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
    57/push-edi
    # 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: slice
    68/push  0/imm32/end
    68/push  0/imm32/start
    89/copy                         3/mod/direct    2/rm32/edx    .           .             .           4/r32/esp   .               .                 # copy esp to edx
$load-labels:loop:
    # clear-stream(line)
    # . . push args
    51/push-ecx
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # read-line-buffered(in, line)
    # . . push args
    51/push-ecx
    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           8/disp8         .                 # push *(ebp+8)
    # . . call
    e8/call  read-line-buffered/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # dump line {{{
#?     # . write(2/stderr, "LL: ")
#?     # . . push args
#?     68/push  "LL: "/imm32
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # write-stream(2/stderr, line)
#?     # . . push args
#?     51/push-ecx
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write-stream/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # . write(2/stderr, "$\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
#?     # }}}
    # if (line->write == 0) break
    81          7/subop/compare     0/mod/indirect  1/rm32/ecx    .           .             .           .           .               0/imm32           # compare *ecx
    0f 84/jump-if-=  $load-labels:end/disp32
    # next-word(line, word-slice)
    # . . push args
    52/push-edx
    51/push-ecx
    # . . call
    e8/call  next-word/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # dump word-slice {{{
#?     # . write(2/stderr, "w: ")
#?     # . . push args
#?     68/push  "w: "/imm32
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # . write-slice-buffered(Stderr, word-slice)
#?     # . . push args
#?     52/push-edx
#?     68/push  Stderr/imm32
#?     # . . call
#?     e8/call  write-slice-buffered/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # . flush(Stderr)
#?     # . . push args
#?     68/push  Stderr/imm32
#?     # . . call
#?     e8/call  flush/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
#?     # . write(2/stderr, "$\n")
#?     # . . push args
#?     68/push  "$\n"/imm32
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # }}}
    # var dest/edi: (addr int) = get-or-insert-slice(labels, word-slice, 12 bytes/row, Heap)
    # . eax = get-or-insert-slice(labels, word-slice, 12 bytes/row, Heap)
    # . . 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
    # . edi = eax
    89/copy                         3/mod/direct    7/rm32/edi    .           .             .           0/r32/eax   .               .                 # copy eax to edi
    # 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
    # var address/esi: 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
    # . esi = eax
    89/copy                         3/mod/direct    6/rm32/esi    .           .             .           0/r32/eax   .               .                 # copy eax to esi
    # *dest = address
    89/copy                         0/mod/indirect  7/rm32/edi    .           .                         6/r32/esi   .               .                 # copy esi to *edi
    #
    e9/jump  $load-labels:loop/disp32
$load-labels: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
    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

# global scratch space for emit-output
== data

emit-output:datum:  # slice
  0/imm32/start
  0/imm32/end

== code

emit-output:  # in: (addr stream byte), out: (addr buffered-file), labels: (addr stream {(handle array byte), address})
    # pseudocode:
    #   var address-of-next-instruction = 0x7c00
    #   var line: (stream byte 512)
    #   line-loop:
    #   while true
    #     clear-stream(line)
    #     read-line(in, line)
    #     if (line->write == 0) break               # end of file
    #     address-of-next-instruction += num-bytes(line)
    #     var far-jump-or-call? = far-jump-or-call?(line)
    #     rewind-stream(line)
    #     while true
    #       var word-slice = next-word(line)
    #       if slice-empty?(word-slice)             # end of line
    #         break
    #       if slice-starts-with?(word-slice, "#")  # comment
    #         break
    #       if label?(word-slice)                # no need for label declarations anymore
    #         goto line-loop                        # don't insert empty lines
    #       if slice-equal?(word-slice, "==")       # no need for segment header lines
    #         word-slice = next-word(line)          # skip segment name
    #         word-slice = next-word(line)
    #         if !slice-empty?(word-slice)
    #           new-address = parse-hex-int-from-slice(word-slice)
    #           write-buffered(out, "# " address-of-next-instruction "\n")
    #           while address-of-next-instruction < new-address
    #             write-buffered("00")
    #             ++address-of-next-instruction
    #           write-buffered(out, "# " address-of-next-instruction "\n")
    #           goto line-loop                      # don't insert empty lines
    #       if length(word-slice) == 2
    #         write-slice-buffered(out, word-slice)
    #         write-buffered(out, " ")
    #         continue
    #       var datum: (addr slice) = next-token-from-slice(word-slice->start, word-slice->end, "/")
    #       var address: (addr int) = get-slice(labels, datum)
    #       if has-metadata?(word-slice, "imm8")
    #         emit(out, *address, 1)
    #       else if has-metadata?(word-slice, "imm16")
    #         emit(out, *address, 2)
    #       else if has-metadata?(word-slice, "imm32")
    #         emit(out, *address, 4)
    #       else if has-metadata?(word-slice, "disp8")
    #         value = *address - address-of-next-instruction
    #         emit(out, value, 1)
    #       else if has-metadata?(word-slice, "disp32")
    #         if far-jump-or-call?
    #           value = *address - address-of-next-instruction
    #         else
    #           value = *address
    #         emit(out, value, 4)
    #       else
    #         abort
    #     write-buffered(out, "\n")
    #
    # registers:
    #   line: ecx
    #   word-slice: edx
    #   address-of-next-instruction: ebx
    #   far-jump-or-call?: edi
    #   address: esi (inner loop only)
    #   temporaries: eax, esi (outer loop)
    #
    # . 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 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: slice
    68/push  0/imm32/end
    68/push  0/imm32/start
    89/copy                         3/mod/direct    2/rm32/edx    .           .             .           4/r32/esp   .               .                 # copy esp to edx
    # var address-of-next-instruction/ebx = 0x7c00
    bb/copy-to-ebx  0x7c00/imm32
$emit-output:line-loop:
    # clear-stream(line)
    # . . push args
    51/push-ecx
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # read-line(in, line)
    # . . push args
    51/push-ecx
    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           8/disp8         .                 # push *(ebp+8)
    # . . call
    e8/call  read-line/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # dump line {{{
#?     # . write(2/stderr, "LL: ")
#?     # . . push args
#?     68/push  "LL: "/imm32
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # write-stream(2/stderr, line)
#?     # . . push args
#?     51/push-ecx
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write-stream/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # . write(2/stderr, "$\n")
#?     # . . push args
#?     68/push  "$\n"/imm32
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # . rewind-stream(line)
#?     # . . push args
#?     51/push-ecx
#?     # . . call
#?     e8/call  rewind-stream/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
#?     # }}}
$emit-output:check-for-end-of-input:
    # if (line->write == 0) break
    81          7/subop/compare     0/mod/indirect  1/rm32/ecx    .           .             .           .           .               0/imm32           # compare *ecx
    0f 84/jump-if-=  $emit-output:end/disp32
    # address-of-next-instruction += num-bytes(line)
    # . eax = num-bytes(line)
    # . . push args
    51/push-ecx
    # . . call
    e8/call  num-bytes/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # . ebx += eax
    01/add                          3/mod/direct    3/rm32/ebx    .           .             .           0/r32/eax   .               .                 # add eax to ebx
    # var far-jump-or-call?/edi: boolean = far-jump-or-call?(line)
    # . . push args
    51/push-ecx
    # . . call
    e8/call  far-jump-or-call?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # rewind-stream(line)
    # . . push args
    51/push-ecx
    # . . call
    e8/call  rewind-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
$emit-output:word-loop:
    # next-word(line, word-slice)
    # . . push args
    52/push-edx
    51/push-ecx
    # . . call
    e8/call  next-word/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # dump word-slice {{{
#?     # . write(2/stderr, "w: ")
#?     # . . push args
#?     68/push  "w: "/imm32
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # . write-slice-buffered(Stderr, word-slice)
#?     # . . push args
#?     52/push-edx
#?     68/push  Stderr/imm32
#?     # . . call
#?     e8/call  write-slice-buffered/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # . flush(Stderr)
#?     # . . push args
#?     68/push  Stderr/imm32
#?     # . . call
#?     e8/call  flush/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
#?     # . write(2/stderr, "$\n")
#?     # . . push args
#?     68/push  "$\n"/imm32
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # }}}
$emit-output:check-for-end-of-line:
    # if (slice-empty?(word-slice)) break
    # . eax = slice-empty?(word-slice)
    # . . push args
    52/push-edx
    # . . call
    e8/call  slice-empty?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # . if (eax != 0) break
    3d/compare-eax-and  0/imm32/false
    0f 85/jump-if-!=  $emit-output:next-line/disp32
$emit-output:check-for-comment:
    # if (slice-starts-with?(word-slice, "#")) break
    # . start/esi = word-slice->start
    8b/copy                         0/mod/indirect  2/rm32/edx    .           .             .           6/r32/esi   .               .                 # copy *edx to esi
    # . c/eax = *start
    31/xor                          3/mod/direct    0/rm32/eax    .           .             .           0/r32/eax   .               .                 # clear eax
    8a/copy-byte                    0/mod/indirect  6/rm32/esi    .           .             .           0/r32/AL    .               .                 # copy byte at *esi to AL
    # . if (eax == '#') break
    3d/compare-eax-and  0x23/imm32/hash
    0f 84/jump-if-=  $emit-output:next-line/disp32
$emit-output:check-for-label:
    # if label?(word-slice) break
    # . 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) break
    3d/compare-eax-and  0/imm32/false
    0f 85/jump-if-!=  $emit-output:line-loop/disp32
$emit-output:check-for-segment-header:
    # if !slice-equal?(word-slice, "==") goto next check
    # . eax = slice-equal?(word-slice, "==")
    # . . push args
    68/push  "=="/imm32
    52/push-edx
    # . . call
    e8/call  slice-equal?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # . if (eax == false) goto next check
    3d/compare-eax-and  0/imm32/false
    0f 84/jump-if-=  $emit-output:2-character/disp32
    # skip segment name
    # . 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 segment address if it exists
    # . 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) goto padding-done
    # . . 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
    # . .
    3d/compare-eax-and  0/imm32/false
    0f 85/jump-if-!=  $emit-output:padding-done/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
    # write-buffered(out, "# " address-of-next-instruction "\n")
    # . write-buffered(out, "# ")
    # . . push args
    68/push  "# "/imm32
    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           0xc/disp8       .                 # push *(ebp+12)
    # . . call
    e8/call  write-buffered/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # . write-int32-hex-buffered(out, address-of-next-instruction)
    # . . push args
    53/push-ebx
    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           0xc/disp8       .                 # push *(ebp+12)
    # . . 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
    # . write-buffered(out, "\n")
    # . . push args
    68/push  Newline/imm32
    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           0xc/disp8       .                 # push *(ebp+12)
    # . . call
    e8/call  write-buffered/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
$emit-output:padding-loop:
    # if (address-of-next-instruction >= new-address) goto padding-loop-done
    39/compare                      3/mod/direct    3/rm32/ebx    .           .             .           0/r32/eax   .               .                 # compare ebx with eax
    73/jump-if-addr>=  $emit-output:padding-loop-done/disp8
    # if (address-of-next-instruction % 8 == 0) write-buffered("\n")
    53/push-ebx
    81          4/subop/and         3/mod/direct    3/rm32/ebx    .           .             .           .           .               7/imm32           # bitwise and of ebx
    81          7/subop/compare     3/mod/direct    3/rm32/ebx    .           .             .           .           .               0/imm32           # compare ebx
    5b/pop-to-ebx
    75/jump-if-!=  $emit-output:padding-core/disp8
    # . write-buffered(out, "\n")
    # . . push args
    68/push  Newline/imm32
    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           0xc/disp8       .                 # push *(ebp+12)
    # . . call
    e8/call  write-buffered/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
$emit-output:padding-core:
    # write-buffered("00")
    # . . push args
    68/push  "00 "/imm32
    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           0xc/disp8       .                 # push *(ebp+12)
    # . . call
    e8/call  write-buffered/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # ++address-of-next-instruction
    43/increment-ebx
    # loop
    eb/jump $emit-output:padding-loop/disp8
$emit-output:padding-loop-done:
    # . write-buffered(out, "\n")
    # . . push args
    68/push  Newline/imm32
    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           0xc/disp8       .                 # push *(ebp+12)
    # . . call
    e8/call  write-buffered/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
$emit-output:padding-done:
    # write-buffered(out, "# " address-of-next-instruction "\n")
    # . write-buffered(out, "# ")
    # . . push args
    68/push  "# "/imm32
    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           0xc/disp8       .                 # push *(ebp+12)
    # . . call
    e8/call  write-buffered/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # . write-int32-hex-buffered(out, address-of-next-instruction)
    # . . push args
    53/push-ebx
    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           0xc/disp8       .                 # push *(ebp+12)
    # . . 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
    # . write-buffered(out, "\n")
    # . . push args
    68/push  Newline/imm32
    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           0xc/disp8       .                 # push *(ebp+12)
    # . . call
    e8/call  write-buffered/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    #
    e9/jump  $emit-output:line-loop/disp32
$emit-output:2-character:
    # if (size(word-slice) != 2) goto next check
    # . eax = size(word-slice)
    8b/copy                         1/mod/*+disp8   2/rm32/edx    .           .             .           0/r32/eax   4/disp8         .                 # copy *(edx+4) to eax
    2b/subtract                     0/mod/indirect  2/rm32/edx    .           .             .           0/r32/eax   .               .                 # subtract *edx from eax
    # . if (eax != 2) goto next check
    3d/compare-eax-and  2/imm32
    75/jump-if-!=  $emit-output:check-metadata/disp8
    # write-slice-buffered(out, word-slice)
    # . . push args
    52/push-edx
    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           0xc/disp8       .                 # push *(ebp+12)
    # . . call
    e8/call  write-slice-buffered/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # write-buffered(out, " ")
    # . . push args
    68/push  Space/imm32
    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           0xc/disp8       .                 # push *(ebp+12)
    # . . call
    e8/call  write-buffered/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # continue
    e9/jump  $emit-output:word-loop/disp32
$emit-output:check-metadata:
    # - if we get here, 'word-slice' must be a label to be looked up
    # datum = next-token-from-slice(word-slice->start, word-slice->end, "/")
    # . . push args
    68/push  emit-output:datum/imm32
    68/push  0x2f/imm32/slash
    ff          6/subop/push        1/mod/*+disp8   2/rm32/edx    .           .             .           .           4/disp8         .                 # push *(edx+4)
    ff          6/subop/push        0/mod/indirect  2/rm32/edx    .           .             .           .           .               .                 # push *edx
    # . . call
    e8/call  next-token-from-slice/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0x10/imm32        # add to esp
#?     # dump datum {{{
#?     # . write(2/stderr, "datum: ")
#?     # . . push args
#?     68/push  "datum: "/imm32
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # . write-slice-buffered(Stderr, datum)
#?     # . . push args
#?     68/push  emit-output:datum/imm32
#?     68/push  Stderr/imm32
#?     # . . call
#?     e8/call  write-slice-buffered/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # . flush(Stderr)
#?     # . . push args
#?     68/push  Stderr/imm32
#?     # . . call
#?     e8/call  flush/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
#?     # . write(2/stderr, "$\n")
#?     # . . push args
#?     68/push  "$\n"/imm32
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # }}}
    # address/esi: (addr int) = get-slice(labels, datum, row-size=12, "label table")
    # . eax = get-slice(labels, datum, row-size=24, "label table")
    # . . push args
    68/push  "label table"/imm32
    68/push  0xc/imm32/row-size
    68/push  emit-output:datum/imm32
    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           0x10/disp8      .                 # push *(ebp+16)
    # . . call
    e8/call  get-slice/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0x10/imm32        # add to esp
    # . esi = eax
    89/copy                         3/mod/direct    6/rm32/esi    .           .             .           0/r32/eax   .               .                 # copy eax to esi
$emit-output:check-imm8:
    # if (!has-metadata?(word-slice, "imm8")) goto next check
    # . eax = has-metadata?(edx, "imm8")
    # . . push args
    68/push  "imm8"/imm32
    52/push-edx
    # . . call
    e8/call  has-metadata?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # . if (eax != false) abort
    3d/compare-eax-and  0/imm32/false
    74/jump-if-=  $emit-output:check-imm16/disp8
$emit-output:emit-imm8:
    # emit-hex(out, *address, 1)
    # . . push args
    68/push  1/imm32
    ff          6/subop/push        0/mod/indirect  6/rm32/esi    .           .             .           .           .               .                 # push *esi
    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           0xc/disp8       .                 # push *(ebp+12)
    # . . call
    e8/call  emit-hex/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # continue
    e9/jump  $emit-output:word-loop/disp32
$emit-output:check-imm16:
    # if (!has-metadata?(word-slice, "imm16")) goto next check
    # . eax = has-metadata?(edx, "imm16")
    # . . push args
    68/push  "imm16"/imm32
    52/push-edx
    # . . call
    e8/call  has-metadata?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # . if (eax == false) goto next check
    3d/compare-eax-and  0/imm32/false
    74/jump-if-=  $emit-output:check-imm32/disp8
#?     # dump *address {{{
#?     # . write(2/stderr, "*address: ")
#?     # . . push args
#?     68/push  "*address: "/imm32
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # . write-int32-hex-buffered(Stderr, *address)
#?     # . . push args
#?     ff          6/subop/push        0/mod/indirect  6/rm32/esi    .           .             .           .           .               .                 # push *esi
#?     68/push  Stderr/imm32
#?     # . . call
#?     e8/call  write-int32-hex-buffered/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # . flush(Stderr)
#?     # . . push args
#?     68/push  Stderr/imm32
#?     # . . call
#?     e8/call  flush/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
#?     # . write(2/stderr, "$\n")
#?     # . . push args
#?     68/push  "$\n"/imm32
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # }}}
$emit-output:emit-imm16:
    # emit-hex(out, *address, 2)
    # . . push args
    68/push  2/imm32
    ff          6/subop/push        0/mod/indirect  6/rm32/esi    .           .             .           .           .               .                 # push *esi
    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           0xc/disp8       .                 # push *(ebp+12)
    # . . call
    e8/call  emit-hex/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # TODO: ensure that the higher 2 bytes are zero
    # continue
    e9/jump  $emit-output:word-loop/disp32
$emit-output:check-imm32:
    # if (!has-metadata?(word-slice, "imm32")) goto next check
    # . eax = has-metadata?(edx, "imm32")
    # . . push args
    68/push  "imm32"/imm32
    52/push-edx
    # . . call
    e8/call  has-metadata?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # . if (eax == false) goto next check
    3d/compare-eax-and  0/imm32/false
    74/jump-if-=  $emit-output:check-disp8/disp8
#?     # dump *address {{{
#?     # . write(2/stderr, "*address: ")
#?     # . . push args
#?     68/push  "*address: "/imm32
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # . write-int32-hex-buffered(Stderr, *address)
#?     # . . push args
#?     ff          6/subop/push        0/mod/indirect  6/rm32/esi    .           .             .           .           .               .                 # push *esi
#?     68/push  Stderr/imm32
#?     # . . call
#?     e8/call  write-int32-hex-buffered/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # . flush(Stderr)
#?     # . . push args
#?     68/push  Stderr/imm32
#?     # . . call
#?     e8/call  flush/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
#?     # . write(2/stderr, "$\n")
#?     # . . push args
#?     68/push  "$\n"/imm32
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # }}}
$emit-output:emit-imm32:
    # emit-hex(out, *address, 4)
    # . . push args
    68/push  4/imm32
    ff          6/subop/push        0/mod/indirect  6/rm32/esi    .           .             .           .           .               .                 # push *esi
    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           0xc/disp8       .                 # push *(ebp+12)
    # . . call
    e8/call  emit-hex/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # continue
    e9/jump  $emit-output:word-loop/disp32
$emit-output:check-disp8:
    # if (!has-metadata?(word-slice, "disp8")) goto next check
    # . eax = has-metadata?(edx, "disp8")
    # . . push args
    68/push  "disp8"/imm32
    52/push-edx
    # . . call
    e8/call  has-metadata?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # . if (eax == false) goto next check
    3d/compare-eax-and  0/imm32/false
    74/jump-if-=  $emit-output:check-disp16/disp8
$emit-output:emit-disp8:
    # emit-hex(out, *address - address-of-next-instruction, 1)
    # . . push args
    68/push  1/imm32
    8b/copy                         0/mod/indirect  6/rm32/esi    .           .             .           0/r32/eax   .               .                 # copy *esi to eax
    29/subtract                     3/mod/direct    0/rm32/eax    .           .             .           3/r32/ebx   .               .                 # subtract ebx from eax
    50/push-eax
    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           0xc/disp8       .                 # push *(ebp+12)
    # . . call
    e8/call  emit-hex/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # continue
    e9/jump  $emit-output:word-loop/disp32
$emit-output:check-disp16:
    # if (!has-metadata?(word-slice, "disp16")) goto next check
    # . eax = has-metadata?(edx, "disp16")
    # . . push args
    68/push  "disp16"/imm32
    52/push-edx
    # . . call
    e8/call  has-metadata?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # . if (eax == false) goto next check
    3d/compare-eax-and  0/imm32/false
    74/jump-if-=  $emit-output:check-disp32/disp8
$emit-output:emit-disp16:
    # emit-hex(out, *address - address-of-next-instruction, 2)
    # . . push args
    68/push  2/imm32
    8b/copy                         0/mod/indirect  6/rm32/esi    .           .             .           0/r32/eax   .               .                 # copy *esi to eax
    29/subtract                     3/mod/direct    0/rm32/eax    .           .             .           3/r32/ebx   .               .                 # subtract ebx from eax
    50/push-eax
    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           0xc/disp8       .                 # push *(ebp+12)
    # . . call
    e8/call  emit-hex/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # continue
    e9/jump  $emit-output:word-loop/disp32
$emit-output:check-disp32:
    # if (!has-metadata?(word-slice, "disp32")) abort
    # . eax = has-metadata?(edx, "disp32")
    # . . push args
    68/push  "disp32"/imm32
    52/push-edx
    # . . call
    e8/call  has-metadata?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # . if (eax == false) abort
    3d/compare-eax-and  0/imm32/false
    0f 84/jump-if-=  $emit-output:abort/disp32
$emit-output:emit-disp32:
    # var value/eax = *address
    8b/copy                         0/mod/indirect  6/rm32/esi    .           .             .           0/r32/eax   .               .                 # copy *esi to eax
    # if (far-jump-or-call?) value -= address-of-next-instruction
    81          7/subop/compare     3/mod/direct    7/rm32/edi    .           .             .           .           .               0/imm32/false     # compare edi
    74/jump-if-=  $emit-output:really-emit-disp32/disp8
    29/subtract                     3/mod/direct    0/rm32/eax    .           .             .           3/r32/ebx   .               .                 # subtract ebx from eax
$emit-output:really-emit-disp32:
    # emit-hex(out, value, 4)
    # . . push args
    68/push  4/imm32
    50/push-eax
    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           0xc/disp8       .                 # push *(ebp+12)
    # . . call
    e8/call  emit-hex/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # continue
    e9/jump  $emit-output:word-loop/disp32
$emit-output:next-line:
    # write-buffered(out, "\n")
    # . . push args
    68/push  Newline/imm32
    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           0xc/disp8       .                 # push *(ebp+12)
    # . . call
    e8/call  write-buffered/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # loop
    e9/jump  $emit-output:line-loop/disp32
$emit-output: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

$emit-output:abort:
    # print(stderr, "missing metadata in " word-slice)
    # . _write(2/stderr, "missing metadata in word ")
    # . . push args
    68/push  "emit-output: missing metadata in "/imm32
    68/push  2/imm32/stderr
    # . . call
    e8/call  _write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # . write-slice-buffered(Stderr, word-slice)
    # . . push args
    52/push-edx
    68/push  Stderr/imm32
    # . . call
    e8/call  write-slice-buffered/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # . flush(Stderr)
    # . . push args
    68/push  Stderr/imm32
    # . . call
    e8/call  flush/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # . syscall(exit, 1)
    bb/copy-to-ebx  1/imm32
    e8/call  syscall_exit/disp32
    # never gets here

test-emit-output-non-far-control-flow:
    # labels turn into absolute addresses if opcodes are not far jumps or calls
    #
    # input:
    #   in:
    #     == code
    #     ab cd ef gh
    #     ij x/disp32
    #     == data
    #     00
    #     34
    #   labels:
    #     - 'x': 0x11223344
    #
    # output:
    #   ab cd ef gh
    #   ij 44 33 22 11
    #   00
    #   34
    #
    # . 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-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
    # . var labels/edx: (stream byte 8*24)
    81          5/subop/subtract    3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc0/imm32        # subtract from esp
    68/push  0xc0/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
    # . var h/ebx: (handle array byte)
    68/push  0/imm32
    68/push  0/imm32
    89/copy                         3/mod/direct    3/rm32/ebx    .           .             .           4/r32/esp   .               .                 # copy esp to ebx
    # 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 cd ef gh\n")
    # . . push args
    68/push  "ab cd ef gh\n"/imm32
    68/push  _test-input-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # . write(_test-input-stream, "ij x/disp32\n")
    # . . push args
    68/push  "ij x/disp32\n"/imm32
    68/push  _test-input-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # . write(_test-input-stream, "== data\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, "34\n")
    # . . push args
    68/push  "34\n"/imm32
    68/push  _test-input-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # . stream-add2(labels, "x", 0x11223344)
    68/push  0x11223344/imm32/label-address
    # . . push handle for "x"
    53/push-ebx
    68/push  "x"/imm32
    68/push  Heap/imm32
    e8/call  copy-array/disp32
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    ff          6/subop/push        1/mod/*+disp8   3/rm32/ebx    .           .             .           .           4/disp8         .                 # push *(ebx+4)
    ff          6/subop/push        0/mod/indirect  3/rm32/ebx    .           .             .           .           .               .                 # push *ebx
    # . . push labels
    52/push-edx
    # . . call
    e8/call  stream-add2/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0x10/imm32        # add to esp
    # component under test
    # . emit-output(_test-input-stream, _test-output-buffered-file, labels)
    # . . push args
    52/push-edx
    68/push  _test-output-buffered-file/imm32
    68/push  _test-input-stream/imm32
    # . . call
    e8/call  emit-output/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # checks
    # . flush(_test-output-buffered-file)
    # . . push args
    68/push  _test-output-buffered-file/imm32
    # . . call
    e8/call  flush/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
#?     # dump output {{{
#?     # . write(2/stderr, "result: ^")
#?     # . . push args
#?     68/push  "result: ^"/imm32
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # . write-stream(2/stderr, _test-output-stream)
#?     # . . push args
#?     68/push  _test-output-stream/imm32
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write-stream/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # . write(2/stderr, "$\n")
#?     # . . push args
#?     68/push  "$\n"/imm32
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # . rewind-stream(_test-output-stream)
#?     # . . push args
#?     68/push  _test-output-stream/imm32
#?     # . . call
#?     e8/call  rewind-stream/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
#?     # }}}
    # . check-next-stream-line-equal(_test-output-stream, "# 0x00007c00", msg)
    # . . push args
    68/push  "F - test-emit-output-non-far-control-flow/0"/imm32
    68/push  "# 0x00007c00"/imm32
    68/push  _test-output-stream/imm32
    # . . call
    e8/call  check-next-stream-line-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # . check-next-stream-line-equal(_test-output-stream, "ab cd ef gh ", msg)
    # . . push args
    68/push  "F - test-emit-output-non-far-control-flow/1"/imm32
    68/push  "ab cd ef gh "/imm32
    68/push  _test-output-stream/imm32
    # . . call
    e8/call  check-next-stream-line-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # . check-next-stream-line-equal(_test-output-stream, "ij 44 33 22 11 ", msg)
    # . . push args
    68/push  "F - test-emit-output-non-far-control-flow/2"/imm32
    68/push  "ij 44 33 22 11 "/imm32
    68/push  _test-output-stream/imm32
    # . . call
    e8/call  check-next-stream-line-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # . check-next-stream-line-equal(_test-output-stream, "# 0x00007c09", msg)
    # . . push args
    68/push  "F - test-emit-output-non-far-control-flow/3"/imm32
    68/push  "# 0x00007c09"/imm32
    68/push  _test-output-stream/imm32
    # . . call
    e8/call  check-next-stream-line-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # . check-next-stream-line-equal(_test-output-stream, "00 ", msg)
    # . . push args
    68/push  "F - test-emit-output-non-far-control-flow/3"/imm32
    68/push  "00 "/imm32
    68/push  _test-output-stream/imm32
    # . . call
    e8/call  check-next-stream-line-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # . check-next-stream-line-equal(_test-output-stream, "34 ", msg)
    # . . push args
    68/push  "F - test-emit-output-non-far-control-flow/4"/imm32
    68/push  "34 "/imm32
    68/push  _test-output-stream/imm32
    # . . call
    e8/call  check-next-stream-line-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # . epilogue
    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
    5d/pop-to-ebp
    c3/return

test-emit-output-with-padding:
    # labels turn into absolute addresses if opcodes are not far jumps or calls
    #
    # input:
    #   in:
    #     == code
    #     ab cd ef gh
    #     == data 0x7c10
    #     34
    #
    # output:
    #   ab cd ef gh
    #   # 0x7c04
    #   00 00 00 00
    #   00 00 00 00 00 00 00 00
    #   # 0x7c10
    #   34
    #
    # . 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-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
    # . var labels/edx: (stream byte 8*24)
    81          5/subop/subtract    3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc0/imm32        # subtract from esp
    68/push  0xc0/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
    # . var h/ebx: (handle array byte)
    68/push  0/imm32
    68/push  0/imm32
    89/copy                         3/mod/direct    3/rm32/ebx    .           .             .           4/r32/esp   .               .                 # copy esp to ebx
    # 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 cd ef gh\n")
    # . . push args
    68/push  "ab cd ef gh\n"/imm32
    68/push  _test-input-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # . write(_test-input-stream, "== data 0x7c10\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, "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
    # component under test
    # . emit-output(_test-input-stream, _test-output-buffered-file, labels)
    # . . push args
    52/push-edx
    68/push  _test-output-buffered-file/imm32
    68/push  _test-input-stream/imm32
    # . . call
    e8/call  emit-output/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # checks
    # . flush(_test-output-buffered-file)
    # . . push args
    68/push  _test-output-buffered-file/imm32
    # . . call
    e8/call  flush/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
#?     # dump output {{{
#?     # . write(2/stderr, "result: ^")
#?     # . . push args
#?     68/push  "result: ^"/imm32
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # . write-stream(2/stderr, _test-output-stream)
#?     # . . push args
#?     68/push  _test-output-stream/imm32
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write-stream/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # . write(2/stderr, "$\n")
#?     # . . push args
#?     68/push  "$\n"/imm32
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # . rewind-stream(_test-output-stream)
#?     # . . push args
#?     68/push  _test-output-stream/imm32
#?     # . . call
#?     e8/call  rewind-stream/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
#?     # }}}
    # . check-next-stream-line-equal(_test-output-stream, "# 0x00007c00", msg)
    # . . push args
    68/push  "F - test-emit-output-with-padding/0"/imm32
    68/push  "# 0x00007c00"/imm32
    68/push  _test-output-stream/imm32
    # . . call
    e8/call  check-next-stream-line-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # . check-next-stream-line-equal(_test-output-stream, "ab cd ef gh ", msg)
    # . . push args
    68/push  "F - test-emit-output-with-padding/1"/imm32
    68/push  "ab cd ef gh "/imm32
    68/push  _test-output-stream/imm32
    # . . call
    e8/call  check-next-stream-line-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # . check-next-stream-line-equal(_test-output-stream, "# 0x00007c04", msg)
    # . . push args
    68/push  "F - test-emit-output-with-padding/0"/imm32
    68/push  "# 0x00007c04"/imm32
    68/push  _test-output-stream/imm32
    # . . call
    e8/call  check-next-stream-line-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # . check-next-stream-line-equal(_test-output-stream, "00 00 00 00 ", msg)
    # . . push args
    68/push  "F - test-emit-output-with-padding/2"/imm32
    68/push  "00 00 00 00 "/imm32
    68/push  _test-output-stream/imm32
    # . . call
    e8/call  check-next-stream-line-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # . check-next-stream-line-equal(_test-output-stream, "00 00 00 00 ", msg)
    # . . push args
    68/push  "F - test-emit-output-with-padding/3"/imm32
    68/push  "00 00 00 00 00 00 00 00 "/imm32
    68/push  _test-output-stream/imm32
    # . . call
    e8/call  check-next-stream-line-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # . check-next-stream-line-equal(_test-output-stream, "# 0x00007c10", msg)
    # . . push args
    68/push  "F - test-emit-output-with-padding/0"/imm32
    68/push  "# 0x00007c10"/imm32
    68/push  _test-output-stream/imm32
    # . . call
    e8/call  check-next-stream-line-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # . check-next-stream-line-equal(_test-output-stream, "34 ", msg)
    # . . push args
    68/push  "F - test-emit-output-with-padding/4"/imm32
    68/push  "34 "/imm32
    68/push  _test-output-stream/imm32
    # . . call
    e8/call  check-next-stream-line-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # . epilogue
    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
    5d/pop-to-ebp
    c3/return

test-emit-output-code-label:
    # labels turn into PC-relative addresses if opcodes are far jumps or calls
    #
    # input:
    #   in:
    #     == code
    #     ab cd
    #     ef gh
    #     e8 l1/disp32
    #   labels:
    #     - 'l1': 0x7c10
    #
    # output:
    #   ab cd
    #   ef gh
    #   e8 07 00 00 00  # 0x7c10 - 0x7c09 = 7
    #
    # . 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-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
    # . var labels/edx: (stream byte 8*24)
    81          5/subop/subtract    3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc0/imm32        # subtract from esp
    68/push  0xc0/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
    # . var h/ebx: (handle array byte)
    68/push  0/imm32
    68/push  0/imm32
    89/copy                         3/mod/direct    3/rm32/ebx    .           .             .           4/r32/esp   .               .                 # copy esp to ebx
    # 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 cd\n")
    # . . push args
    68/push  "ab cd\n"/imm32
    68/push  _test-input-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # . write(_test-input-stream, "ef gh\n")
    # . . push args
    68/push  "ef gh\n"/imm32
    68/push  _test-input-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # . write(_test-input-stream, "e8 l1/disp32\n")
    # . . push args
    68/push  "e8 l1/disp32\n"/imm32
    68/push  _test-input-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # . stream-add2(labels, "l1", 0x7c10)
    68/push  0x7c10/imm32/label-address
    # . . push handle for "l1"
    53/push-ebx
    68/push  "l1"/imm32
    68/push  Heap/imm32
    e8/call  copy-array/disp32
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    ff          6/subop/push        1/mod/*+disp8   3/rm32/ebx    .           .             .           .           4/disp8         .                 # push *(ebx+4)
    ff          6/subop/push        0/mod/indirect  3/rm32/ebx    .           .             .           .           .               .                 # push *ebx
    # . . push labels
    52/push-edx
    # . . call
    e8/call  stream-add2/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0x10/imm32        # add to esp
    # component under test
    # . emit-output(_test-input-stream, _test-output-buffered-file, labels)
    # . . push args
    52/push-edx
    68/push  _test-output-buffered-file/imm32
    68/push  _test-input-stream/imm32
    # . . call
    e8/call  emit-output/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # checks
    # . flush(_test-output-buffered-file)
    # . . push args
    68/push  _test-output-buffered-file/imm32
    # . . call
    e8/call  flush/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
#?     # dump output {{{
#?     # . write(2/stderr, "result: ^")
#?     # . . push args
#?     68/push  "result: ^"/imm32
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # . write-stream(2/stderr, _test-output-stream)
#?     # . . push args
#?     68/push  _test-output-stream/imm32
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write-stream/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # . write(2/stderr, "$\n")
#?     # . . push args
#?     68/push  "$\n"/imm32
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # . rewind-stream(_test-output-stream)
#?     # . . push args
#?     68/push  _test-output-stream/imm32
#?     # . . call
#?     e8/call  rewind-stream/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
#?     # }}}
    # . check-next-stream-line-equal(_test-output-stream, "# 0x00007c00", msg)
    # . . push args
    68/push  "F - test-emit-output-code-label/0"/imm32
    68/push  "# 0x00007c00"/imm32
    68/push  _test-output-stream/imm32
    # . . call
    e8/call  check-next-stream-line-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # . check-next-stream-line-equal(_test-output-stream, "ab cd ", msg)
    # . . push args
    68/push  "F - test-emit-output-code-label/1"/imm32
    68/push  "ab cd "/imm32
    68/push  _test-output-stream/imm32
    # . . call
    e8/call  check-next-stream-line-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # . check-next-stream-line-equal(_test-output-stream, "ef gh ", msg)
    # . . push args
    68/push  "F - test-emit-output-code-label/2"/imm32
    68/push  "ef gh "/imm32
    68/push  _test-output-stream/imm32
    # . . call
    e8/call  check-next-stream-line-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # . check-next-stream-line-equal(_test-output-stream, "e8 07 00 00 00 ", msg)
    # . . push args
    68/push  "F - test-emit-output-code-label/3"/imm32
    68/push  "e8 07 00 00 00 "/imm32
    68/push  _test-output-stream/imm32
    # . . call
    e8/call  check-next-stream-line-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # . epilogue
    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
    5d/pop-to-ebp
    c3/return

test-emit-output-code-label-absolute:
    # labels can also convert to absolute addresses
    #
    # input:
    #   in:
    #     == code
    #     ab cd
    #     ef gh
    #     ij l1/imm32
    #   labels:
    #     - 'l1': 0x1056
    #
    # output:
    #   ab cd
    #   ef gh
    #   ij 56 10 00 00
    #
    # . 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-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
    # . var labels/edx: (stream byte 8*24)
    81          5/subop/subtract    3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc0/imm32        # subtract from esp
    68/push  0xc0/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
    # . var h/ebx: (handle array byte)
    68/push  0/imm32
    68/push  0/imm32
    89/copy                         3/mod/direct    3/rm32/ebx    .           .             .           4/r32/esp   .               .                 # copy esp to ebx
    # initialize input
    # . write(_test-input-stream, "== code 0x1000\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 cd\n")
    # . . push args
    68/push  "ab cd\n"/imm32
    68/push  _test-input-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # . write(_test-input-stream, "ef gh\n")
    # . . push args
    68/push  "ef gh\n"/imm32
    68/push  _test-input-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # . write(_test-input-stream, "ij l1/imm32\n")
    # . . push args
    68/push  "ij l1/imm32\n"/imm32
    68/push  _test-input-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # . stream-add2(labels, "l1", 0x1056)
    68/push  0x1056/imm32/label-address
    # . . push handle for "l1"
    53/push-ebx
    68/push  "l1"/imm32
    68/push  Heap/imm32
    e8/call  copy-array/disp32
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    ff          6/subop/push        1/mod/*+disp8   3/rm32/ebx    .           .             .           .           4/disp8         .                 # push *(ebx+4)
    ff          6/subop/push        0/mod/indirect  3/rm32/ebx    .           .             .           .           .               .                 # push *ebx
    # . . push labels
    52/push-edx
    # . . call
    e8/call  stream-add2/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0x10/imm32        # add to esp
    # component under test
    # . emit-output(_test-input-stream, _test-output-buffered-file, labels)
    # . . push args
    52/push-edx
    68/push  _test-output-buffered-file/imm32
    68/push  _test-input-stream/imm32
    # . . call
    e8/call  emit-output/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # checks
    # . flush(_test-output-buffered-file)
    # . . push args
    68/push  _test-output-buffered-file/imm32
    # . . call
    e8/call  flush/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
#?     # dump output {{{
#?     # . write(2/stderr, "result: ^")
#?     # . . push args
#?     68/push  "result: ^"/imm32
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # . write-stream(2/stderr, _test-output-stream)
#?     # . . push args
#?     68/push  _test-output-stream/imm32
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write-stream/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # . write(2/stderr, "$\n")
#?     # . . push args
#?     68/push  "$\n"/imm32
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # . rewind-stream(_test-output-stream)
#?     # . . push args
#?     68/push  _test-output-stream/imm32
#?     # . . call
#?     e8/call  rewind-stream/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
#?     # }}}
    # . check-next-stream-line-equal(_test-output-stream, "# 0x00007c00", msg)
    # . . push args
    68/push  "F - test-emit-output-code-label-absolute/0"/imm32
    68/push  "# 0x00007c00"/imm32
    68/push  _test-output-stream/imm32
    # . . call
    e8/call  check-next-stream-line-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # . check-next-stream-line-equal(_test-output-stream, "ab cd ", msg)
    # . . push args
    68/push  "F - test-emit-output-code-label-absolute/1"/imm32
    68/push  "ab cd "/imm32
    68/push  _test-output-stream/imm32
    # . . call
    e8/call  check-next-stream-line-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # . check-next-stream-line-equal(_test-output-stream, "ef gh ", msg)
    # . . push args
    68/push  "F - test-emit-output-code-label-absolute/2"/imm32
    68/push  "ef gh "/imm32
    68/push  _test-output-stream/imm32
    # . . call
    e8/call  check-next-stream-line-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # . check-next-stream-line-equal(_test-output-stream, "ij f9 ff ff ff ", msg)
    # . . push args
    68/push  "F - test-emit-output-code-label-absolute/3"/imm32
    68/push  "ij 56 10 00 00 "/imm32
    68/push  _test-output-stream/imm32
    # . . call
    e8/call  check-next-stream-line-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # . epilogue
    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
    5d/pop-to-ebp
    c3/return

# reads line to make some checks
# don't assume the read state of line after calling this function
far-jump-or-call?:  # line: (addr stream byte) -> result/edi: boolean
    # . 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
    # ecx = line
    8b/copy                         1/mod/*+disp8   5/rm32/ebp    .           .             .           1/r32/ecx   8/disp8         .                 # copy *(ebp+8) to ecx
    # var word-slice/edx: slice
    68/push  0/imm32/end
    68/push  0/imm32/start
    89/copy                         3/mod/direct    2/rm32/edx    .           .             .           4/r32/esp   .               .                 # copy esp to edx
    # var datum-slice/ebx: slice
    68/push  0/imm32/end
    68/push  0/imm32/start
    89/copy                         3/mod/direct    3/rm32/ebx    .           .             .           4/r32/esp   .               .                 # copy esp to ebx
    # result = false
    bf/copy-to-edi  0/imm32/false
$far-jump-or-call?:check-first-word:
    # 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)) return false
    # . eax = slice-empty?(word-slice)
    # . . push args
    52/push-edx
    # . . call
    e8/call  slice-empty?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # . if (eax != 0) return
    3d/compare-eax-and  0/imm32/false
    0f 85/jump-if-!=  $far-jump-or-call?:end/disp32
    # datum = next-token-from-slice(word-slice->start, word-slice->end, "/")
    # . . push args
    53/push-ebx
    68/push  0x2f/imm32/slash
    ff          6/subop/push        1/mod/*+disp8   2/rm32/edx    .           .             .           .           4/disp8         .                 # push *(edx+4)
    ff          6/subop/push        0/mod/indirect  2/rm32/edx    .           .             .           .           .               .                 # push *edx
    # . . call
    e8/call  next-token-from-slice/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0x10/imm32        # add to esp
    # if (datum-slice == "e8") return true
    # . eax = slice-equal?(datum-slice, "e8")
    # . . push args
    68/push  "e8"/imm32
    53/push-ebx
    # . . 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) return true
    3d/compare-eax-and  0/imm32/false
    75/jump-if-!=  $far-jump-or-call?:return-true/disp8
    # if (datum-slice == "e9") return true
    # . eax = slice-equal?(datum-slice, "e9")
    # . . push args
    68/push  "e9"/imm32
    53/push-ebx
    # . . 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) return true
    3d/compare-eax-and  0/imm32/false
    75/jump-if-!=  $far-jump-or-call?:return-true/disp8
    # if (datum-slice != "0f") return false
    # . eax = slice-equal?(datum-slice, "0f")
    # . . push args
    68/push  "0f"/imm32
    53/push-ebx
    # . . 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) return
    3d/compare-eax-and  0/imm32/false
    74/jump-if-=  $far-jump-or-call?:end/disp8
$far-jump-or-call?:check-second-word:
    # 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)) return false
    # . eax = slice-empty?(word-slice)
    # . . push args
    52/push-edx
    # . . call
    e8/call  slice-empty?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # . if (eax != 0) return
    3d/compare-eax-and  0/imm32/false
    75/jump-if-!=  $far-jump-or-call?:end/disp8
    # if datum of word-slice does not start with "8", return false
    # . start/eax = word-slice->start
    8b/copy                         0/mod/indirect  2/rm32/edx    .           .             .           0/r32/eax   .               .                 # copy *edx to eax
    # . c/eax = *start
    8a/copy-byte                    0/mod/indirect  0/rm32/eax    .           .             .           0/r32/AL    .               .                 # copy byte at *eax to AL
    25/and-eax-with  0xff/imm32
    # . if (eax != '8') return
    3d/compare-eax-and  0x38/imm32/8
    75/jump-if-!=  $far-jump-or-call?:end/disp8
    # otherwise return true
$far-jump-or-call?:return-true:
    bf/copy-to-edi  1/imm32/true
$far-jump-or-call?:end:
    # . reclaim locals
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0x10/imm32        # add to esp
    # . restore registers
    5b/pop-to-ebx
    5a/pop-to-edx
    59/pop-to-ecx
    58/pop-to-eax
    # . 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

stream-add2:  # in: (addr stream byte), key: handle, val: int
    # . 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 = in
    8b/copy                         1/mod/*+disp8   5/rm32/ebp    .           .             .           6/r32/esi   8/disp8         .                 # copy *(ebp+8) to esi
    # curr/eax = &in->data[in->write]
    # . eax = in->write
    8b/copy                         0/mod/indirect  6/rm32/esi    .           .             .           0/r32/eax   .               .                 # copy *esi to eax
    # . eax = esi+eax+12
    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    6/base/esi  0/index/eax   .           0/r32/eax   0xc/disp8       .                 # copy esi+eax+12 to eax
    # max/edx = &in->data[in->size]
    # . edx = in->size
    8b/copy                         1/mod/*+disp8   6/rm32/esi    .           .             .           2/r32/edx   8/disp8         .                 # copy *(esi+8) to edx
    # . edx = esi+edx+12
    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    6/base/esi  2/index/edx   .           2/r32/edx   0xc/disp8       .                 # copy esi+edx+12 to edx
    # if (curr >= max) abort
    39/compare                      3/mod/direct    0/rm32/eax    .           .             .           2/r32/edx   .               .                 # compare eax with edx
    73/jump-if-addr>=  $stream-add2:abort/disp8
    # *curr = key->alloc-id
    8b/copy                         1/mod/*+disp8   5/rm32/ebp    .           .                         1/r32/ecx   0xc/disp8       .                 # copy *(ebp+12) to ecx
    89/copy                         0/mod/indirect  0/rm32/eax    .           .             .           1/r32/ecx   .               .                 # copy ecx to *eax
    # curr += 4
    05/add-to-eax  4/imm32
    # if (curr >= max) abort
    39/compare                      3/mod/direct    0/rm32/eax    .           .             .           2/r32/edx   .               .                 # compare eax with edx
    73/jump-if-addr>=  $stream-add2:abort/disp8
    # *curr = key->payload
    8b/copy                         1/mod/*+disp8   5/rm32/ebp    .           .                         1/r32/ecx   0x10/disp8      .                 # copy *(ebp+16) to ecx
    89/copy                         0/mod/indirect  0/rm32/eax    .           .             .           1/r32/ecx   .               .                 # copy ecx to *eax
    # curr += 4
    05/add-to-eax  4/imm32
    # if (curr >= max) abort
    39/compare                      3/mod/direct    0/rm32/eax    .           .             .           2/r32/edx   .               .                 # compare eax with edx
    73/jump-if-addr>=  $stream-add2:abort/disp8
    # *curr = val
    8b/copy                         1/mod/*+disp8   5/rm32/ebp    .           .                         1/r32/ecx   0x14/disp8      .                 # copy *(ebp+20) to ecx
    89/copy                         0/mod/indirect  0/rm32/eax    .           .             .           1/r32/ecx   .               .                 # copy ecx to *eax
    # in->write += 0xc
    81          0/subop/add         0/mod/indirect  6/rm32/esi    .           .             .           .           .               0xc/imm32         # add to *esi
$stream-add2: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

$stream-add2:abort:
    # . _write(2/stderr, error)
    # . . push args
    68/push  "overflow in stream-add2\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

# 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

num-bytes:  # line: (addr stream byte) -> eax: int
    # pseudocode:
    #   result = 0
    #   while true
    #     var word-slice = next-word(line)
    #     if slice-empty?(word-slice)             # end of line
    #       break
    #     if slice-starts-with?(word-slice, "#")  # comment
    #       break
    #     if label?(word-slice)                # no need for label declarations anymore
    #       break
    #     if slice-equal?(word-slice, "==")
    #       break                                 # no need for segment header lines
    #     result += compute-width(word-slice)
    #   return result
    #
    # . 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
    53/push-ebx
    # var result/eax = 0
    31/xor                          3/mod/direct    0/rm32/eax    .           .             .           0/r32/eax   .               .                 # clear eax
    # var word-slice/ecx: slice
    68/push  0/imm32/end
    68/push  0/imm32/start
    89/copy                         3/mod/direct    1/rm32/ecx    .           .             .           4/r32/esp   .               .                 # copy esp to ecx
#?     # dump line {{{
#?     # . write(2/stderr, "LL: ")
#?     # . . push args
#?     68/push  "LL: "/imm32
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # write-stream(2/stderr, line)
#?     # . . push args
#?     ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           8/disp8         .                 # push *(ebp+8)
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write-stream/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # . write(2/stderr, "$\n")
#?     # . . push args
#?     68/push  "$\n"/imm32
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # }}}
    # . rewind-stream(line)
    # . . push args
    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           8/disp8         .                 # push *(ebp+8)
    # . . call
    e8/call  rewind-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
$num-bytes:loop:
    # next-word(line, word-slice)
    # . . push args
    51/push-ecx
    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           8/disp8         .                 # push *(ebp+8)
    # . . call
    e8/call  next-word/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # dump word-slice {{{
#?     # . write(2/stderr, "AA: ")
#?     # . . push args
#?     68/push  "AA: "/imm32
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # . clear-stream($Stderr->buffer)
#?     # . . push args
#?     68/push  $Stderr->buffer/imm32
#?     # . . call
#?     e8/call  clear-stream/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
#?     # . write-slice-buffered(Stderr, word-slice)
#?     # . . push args
#?     51/push-ecx
#?     68/push  Stderr/imm32
#?     # . . call
#?     e8/call  write-slice-buffered/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # . flush(Stderr)
#?     # . . push args
#?     68/push  Stderr/imm32
#?     # . . call
#?     e8/call  flush/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
#?     # . write(2/stderr, "$\n")
#?     # . . push args
#?     68/push  "$\n"/imm32
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
#?     # }}}
$num-bytes:check0:
    # if (slice-empty?(word-slice)) break
    # . save result
    50/push-eax
    # . eax = slice-empty?(word-slice)
    # . . push args
    51/push-ecx
    # . . call
    e8/call  slice-empty?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # . if (eax != false) break
    3d/compare-eax-and  0/imm32/false
    # . restore result now that ZF is set
    58/pop-to-eax
    75/jump-if-!=  $num-bytes:end/disp8
$num-bytes:check-for-comment:
    # if (slice-starts-with?(word-slice, "#")) break
    # . start/edx = word-slice->start
    8b/copy                         0/mod/indirect  1/rm32/ecx    .           .             .           2/r32/edx   .               .                 # copy *ecx to edx
    # . c/ebx = *start
    31/xor                          3/mod/direct    3/rm32/ebx    .           .             .           3/r32/ebx   .               .                 # clear ebx
    8a/copy-byte                    0/mod/indirect  2/rm32/edx    .           .             .           3/r32/BL    .               .                 # copy byte at *edx to BL
    # . if (ebx == '#') break
    81          7/subop/compare     3/mod/direct    3/rm32/ebx    .           .             .           .           .               0x23/imm32/hash   # compare ebx
    74/jump-if-=  $num-bytes:end/disp8
$num-bytes:check-for-label:
    # if (slice-ends-with?(word-slice, ":")) break
    # . end/edx = word-slice->end
    8b/copy                         1/mod/*+disp8   1/rm32/ecx    .           .             .           2/r32/edx   4/disp8         .                 # copy *(ecx+4) to edx
    # . c/ebx = *(end-1)
    31/xor                          3/mod/direct    3/rm32/ebx    .           .             .           3/r32/ebx   .               .                 # clear ebx
    8a/copy-byte                    1/mod/*+disp8   2/rm32/edx    .           .             .           3/r32/BL    -1/disp8        .                 # copy byte at *ecx to BL
    # . if (ebx == ':') break
    81          7/subop/compare     3/mod/direct    3/rm32/ebx    .           .             .           .           .               0x3a/imm32/colon  # compare ebx
    74/jump-if-=  $num-bytes:end/disp8
$num-bytes:check-for-segment-header:
    # if (slice-equal?(word-slice, "==")) break
    # . push result
    50/push-eax
    # . eax = slice-equal?(word-slice, "==")
    # . . push args
    68/push  "=="/imm32
    51/push-ecx
    # . . call
    e8/call  slice-equal?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # . if (eax != false) break
    3d/compare-eax-and  0/imm32/false
    # . restore result now that ZF is set
    58/pop-to-eax
    75/jump-if-!=  $num-bytes:end/disp8
$num-bytes:loop-body:
    # result += compute-width-of-slice(word-slice)
    # . copy result to edx
    89/copy                         3/mod/direct    2/rm32/edx    .           .             .           0/r32/eax   .               .                 # copy eax to edx
    # . eax = compute-width-of-slice(word-slice)
    # . . push args
    51/push-ecx
    # . . call
    e8/call compute-width-of-slice/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # . eax += result
    01/add                          3/mod/direct    0/rm32/eax    .           .             .           2/r32/edx   .               .                 # add edx to eax
    e9/jump  $num-bytes:loop/disp32
$num-bytes:end:
    # . rewind-stream(line)
    # . . push args
    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           8/disp8         .                 # push *(ebp+8)
    # . . call
    e8/call  rewind-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # . reclaim locals
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # . restore registers
    5b/pop-to-ebx
    5a/pop-to-edx
    59/pop-to-ecx
    # . epilogue
    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
    5d/pop-to-ebp
    c3/return

test-num-bytes-handles-empty-string:
    # if a line starts with '#', return 0
    # . 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-output-stream)
    # . . push args
    68/push  _test-output-stream/imm32
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # no contents in input
    # eax = num-bytes(_test-input-stream)
    # . . push args
    68/push  _test-input-stream/imm32
    # . . call
    e8/call  num-bytes/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # check-ints-equal(eax, 0, msg)
    # . . push args
    68/push  "F - test-num-bytes-handles-empty-string"/imm32
    68/push  0/imm32/true
    50/push-eax
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # . epilogue
    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
    5d/pop-to-ebp
    c3/return

test-num-bytes-ignores-comments:
    # if a line starts with '#', return 0
    # . 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-output-stream)
    # . . push args
    68/push  _test-output-stream/imm32
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # initialize input
    # . write(_test-input-stream, "# abcd")
    # . . push args
    68/push  "# abcd"/imm32
    68/push  _test-input-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # eax = num-bytes(_test-input-stream)
    # . . push args
    68/push  _test-input-stream/imm32
    # . . call
    e8/call  num-bytes/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # check-ints-equal(eax, 0, msg)
    # . . push args
    68/push  "F - test-num-bytes-ignores-comments"/imm32
    68/push  0/imm32/true
    50/push-eax
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # . epilogue
    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
    5d/pop-to-ebp
    c3/return

test-num-bytes-ignores-labels:
    # if the first word ends with ':', return 0
    # . 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-output-stream)
    # . . push args
    68/push  _test-output-stream/imm32
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # initialize input
    # . write(_test-input-stream, "ab: # cd")
    # . . push args
    68/push  "ab: # cd"/imm32
    68/push  _test-input-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # eax = num-bytes(_test-input-stream)
    # . . push args
    68/push  _test-input-stream/imm32
    # . . call
    e8/call  num-bytes/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # check-ints-equal(eax, 0, msg)
    # . . push args
    68/push  "F - test-num-bytes-ignores-labels"/imm32
    68/push  0/imm32/true
    50/push-eax
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # . epilogue
    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
    5d/pop-to-ebp
    c3/return

test-num-bytes-ignores-segment-headers:
    # if the first word is '==', return 0
    # . 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-output-stream)
    # . . push args
    68/push  _test-output-stream/imm32
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # initialize input
    # . write(_test-input-stream, "== ab cd")
    # . . push args
    68/push  "== ab cd"/imm32
    68/push  _test-input-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # eax = num-bytes(_test-input-stream)
    # . . push args
    68/push  _test-input-stream/imm32
    # . . call
    e8/call  num-bytes/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # check-ints-equal(eax, 0, msg)
    # . . push args
    68/push  "F - test-num-bytes-ignores-segment-headers"/imm32
    68/push  0/imm32/true
    50/push-eax
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # . epilogue
    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
    5d/pop-to-ebp
    c3/return

test-num-bytes-counts-words-by-default:
    # without metadata, count words
    # . 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-output-stream)
    # . . push args
    68/push  _test-output-stream/imm32
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # initialize input
    # . write(_test-input-stream, "ab cd ef")
    # . . push args
    68/push  "ab cd ef"/imm32
    68/push  _test-input-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # eax = num-bytes(_test-input-stream)
    # . . push args
    68/push  _test-input-stream/imm32
    # . . call
    e8/call  num-bytes/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # check-ints-equal(eax, 3, msg)
    # . . push args
    68/push  "F - test-num-bytes-counts-words-by-default"/imm32
    68/push  3/imm32/true
    50/push-eax
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # . epilogue
    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
    5d/pop-to-ebp
    c3/return

test-num-bytes-ignores-trailing-comment:
    # trailing comments appropriately ignored
    # . 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-output-stream)
    # . . push args
    68/push  _test-output-stream/imm32
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # initialize input
    # . write(_test-input-stream, "ab cd # ef")
    # . . push args
    68/push  "ab cd # ef"/imm32
    68/push  _test-input-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # eax = num-bytes(_test-input-stream)
    # . . push args
    68/push  _test-input-stream/imm32
    # . . call
    e8/call  num-bytes/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # check-ints-equal(eax, 2, msg)
    # . . push args
    68/push  "F - test-num-bytes-ignores-trailing-comment"/imm32
    68/push  2/imm32/true
    50/push-eax
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # . epilogue
    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
    5d/pop-to-ebp
    c3/return

test-num-bytes-handles-imm32:
    # if a word has the /imm32 metadata, count it as 4 bytes
    # . 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-output-stream)
    # . . push args
    68/push  _test-output-stream/imm32
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # initialize input
    # . write(_test-input-stream, "ab cd/imm32 ef")
    # . . push args
    68/push  "ab cd/imm32 ef"/imm32
    68/push  _test-input-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # eax = num-bytes(_test-input-stream)
    # . . push args
    68/push  _test-input-stream/imm32
    # . . call
    e8/call  num-bytes/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # check-ints-equal(eax, 6, msg)
    # . . push args
    68/push  "F - test-num-bytes-handles-imm32"/imm32
    68/push  6/imm32/true
    50/push-eax
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # . 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
