path: root/subx/apps/pack.subx

# Read a text file of SubX instructions from stdin, and convert it into a list
# of whitespace-separated ascii hex bytes on stdout, suitable to be further
# processed by apps/hex.
#
# To run (from the subx/ directory):
#   $ ./subx translate *.subx apps/pack.subx -o apps/pack
#   $ echo '05/add-to-EAX 0x20/imm32'  |./subx run apps/pack
# Expected output:
#   05 20 00 00 00  # 05/add-to-EAX 0x20/imm32
# The original instruction gets included as a comment at the end of each
# converted line.
#
# There's zero error-checking. For now we assume the input program is valid.
# We'll continue to rely on the C++ version for error messages.
#
# Label definitions and uses are left untouched for a future 'pass'.

== 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

    # for debugging: run a single test
#?     e8/call test-convert-instruction-passes-labels-through/disp32
#?     8b/copy                         0/mod/indirect  5/rm32/.disp32            .             .           3/r32/EBX   Num-test-failures/disp32          # copy *Num-test-failures to EBX
#?     eb/jump  $main:end/disp8

# main: run tests if necessary, convert stdin if not
    # . prolog
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # - if argc > 1 and argv[1] == "test" then return run_tests()
    # . argc > 1
    81          7/subop/compare     1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0/disp8         1/imm32           # compare *EBP
    7e/jump-if-lesser-or-equal  $run-main/disp8
    # . argv[1] == "test"
    # . . push args
    68/push  "test"/imm32
    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
    # . . call
    e8/call  kernel-string-equal?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # . check result
    3d/compare-EAX  1/imm32
    75/jump-if-not-equal  $run-main/disp8
    # . run-tests()
    e8/call  run-tests/disp32
    8b/copy                         0/mod/indirect  5/rm32/.disp32            .             .           3/r32/EBX   Num-test-failures/disp32          # copy *Num-test-failures to EBX
    eb/jump  $main:end/disp8
$run-main:
    # - otherwise convert stdin
    # var ed/EAX : exit-descriptor
    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # subtract from ESP
    89/copy                         3/mod/direct    0/rm32/EAX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EAX
    # configure ed to really exit()
    # . ed->target = 0
    c7          0/subop/copy        0/mod/direct    0/rm32/EAX    .           .             .           .           .               0/imm32           # copy to *EAX
    # return convert(Stdin, 1/stdout, 2/stderr, ed)
    # . . push args
    50/push-EAX/ed
    68/push  Stderr/imm32
    68/push  Stdout/imm32
    68/push  Stdin/imm32
    # . . call
    e8/call  convert/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
    # . syscall(exit, 0)
    bb/copy-to-EBX  0/imm32
$main:end:
    b8/copy-to-EAX  1/imm32/exit
    cd/syscall  0x80/imm8

# - big picture
# We'll operate on each line/instruction in isolation. That way we only need to
# allocate memory for converting a single instruction.
#
# To pack an entire file:
#   read every line
#   convert it
#
# primary state: line
#   stream of 512 bytes; abort if it ever overflows

convert:  # in : (address buffered-file), out : (address buffered-file) -> <void>
    # pseudocode:
    #   line = new-stream(512, 1)
    #   repeatedly
    #     clear-stream(line)
    #     EAX = read-line(in, line)
    #     if EAX == EOF break
    #     convert-instruction(line, out, err, ed)
    #   flush(out)
    #
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # . save registers
    51/push-ECX
    # var line/ECX : (address stream byte) = stream(512)
    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x200/imm32       # subtract from ESP
    68/push  0x200/imm32/length
    68/push  0/imm32/read
    68/push  0/imm32/write
    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
$convert:loop:
    # clear-stream(ECX)
    # . . 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
    # EAX = 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  convert-instruction/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # if EAX == 0xffffffff break
    3d/compare-with-EAX  0xffffffff/imm32
    74/jump-if-equal  $convert:break/disp8
    # convert-instruction(line, out, err, ed)
    # . . push args
    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
    51/push-ECX
    # . . call
    e8/call  convert-instruction/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
$convert:break:
    # flush(out)
    # . . push args
    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
    # . . call
    e8/call  flush/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
$convert:end:
    # . restore registers
    59/pop-to-ECX
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

# - To pack an instruction, following the C++ version:
# read first word as opcode and write-slice
# if 0f or f2 or f3 read second opcode and write-slice
# if 'f2 0f' or 'f3 0f' read third opcode and write-slice
# while true:
#   word-slice = next-word
#   if empty(word-slice) break
#   if has metadata 'mod', parse into mod
#   if has metadata 'rm32', parse into rm32
#   if has metadata 'r32', parse into r32
#   if has metadata 'subop', parse into r32
# if at least one of the 3 was present, print-byte
# while true:
#   word-slice = next-word
#   if empty(word-slice) break
#   if has metadata 'base', parse into base
#   if has metadata 'index', parse into index
#   if has metadata 'scale', parse into scale
# if at least one of the 3 was present, print-byte
# parse errors => <abort>
# while true:
#   word-slice = next-word
#   if empty(word-slice) break
#   if has metadata 'disp8', emit as 1 byte
#   if has metadata 'disp16', emit as 2 bytes
#   if has metadata 'disp32', emit as 4 bytes
# while true:
#   word-slice = next-word
#   if empty(word-slice) break
#   if has metadata 'imm8', emit
#   if has metadata 'imm32', emit as 4 bytes
# finally, emit line prefixed with a '  # '

# simplifications since we perform zero error handling (continuing to rely on the C++ version for that):
#   missing fields are always 0-filled
#   bytes never mentioned are silently dropped; if you don't provide /mod, /rm32 or /r32 you don't get a 0 modrm byte. You get *no* modrm byte.
#   in case of conflict, last operand with a name is recognized
#   silently drop extraneous operands
#   unceremoniously abort on non-numeric operands except disp or imm

# conceptual hierarchy within a line:
#   line = words separated by ' ', maybe followed by comment starting with '#'
#   word = name until '/', then 0 or more metadata separated by '/'
#
# we won't bother saving the internal structure of lines; reparsing should be cheap using three primitives:
#   next-token(stream, delim char) -> slice (start, end pointers)
#   next-token(stream, slice, delim char) -> slice'
#   slice-equal?(slice, string)

convert-instruction:  # line : (address stream byte), out : (address buffered-file) -> <void>
    # pseudocode:
    #   word-slice = next-word
    #   if *word-slice->start == '#'
    #     write-stream-buffered(out, line)
    #     return
    #   if starts-with(word-slice, '==')
    #     segment-name = next-word()
    #     write-stream-buffered(out, line)
    #     return
    #   if segment-name != 'code'
    #     write-stream-buffered(out, line)
    #     return
    #
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # . save registers
    51/push-ECX
    # var word-slice/ECX = {0, 0}
    68/push  0/imm32/end
    68/push  0/imm32/start
    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
    # next-word(line, word-slice)
    # . . push args
    51/push-ECX
    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
    # . . call
    e8/call  next-word/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
$convert-instruction:pass-line-through:
    # write-stream-buffered(out, line)
    # . . push args
    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
    # . . call
    e8/call  write-stream-buffered/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
$convert-instruction:end:
    # . restore registers
    59/pop-to-ECX
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

test-convert-instruction-passes-comments-through:
    # if a line starts with '#', pass it along unchanged
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # setup
    # . clear-stream(_test-stream)
    # . . push args
    68/push  _test-stream/imm32
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # . clear-stream(_test-buffered-file+4)
    # . . push args
    b8/copy-to-EAX  _test-buffered-file/imm32
    05/add-to-EAX  4/imm32
    50/push-EAX
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # . clear-stream(_test-tmp-stream)
    # . . push args
    68/push  _test-tmp-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-tmp-stream, "# abcd")
    # . . push args
    68/push  "# abcd"/imm32
    68/push  _test-tmp-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # convert-instruction(_test-tmp-stream, _test-buffered-file)
    # . . push args
    68/push  _test-buffered-file/imm32
    68/push  _test-tmp-stream/imm32
    # . . call
    e8/call  convert-instruction/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # check that the write happened as expected
    # . flush(_test-buffered-file)
    # . . push args
    68/push  _test-buffered-file/imm32
    # . . call
    e8/call  flush/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # . check-stream-equal(_test-stream, "# abcd", msg)
    # . . push args
    68/push  "F - test-convert-instruction-passes-comments-through"/imm32
    68/push  "# abcd"/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  check-stream-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

test-convert-instruction-passes-segment-headers-through:
    # if a line starts with '==', pass it along unchanged
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # setup
    # . clear-stream(_test-stream)
    # . . push args
    68/push  _test-stream/imm32
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # . clear-stream(_test-buffered-file+4)
    # . . push args
    b8/copy-to-EAX  _test-buffered-file/imm32
    05/add-to-EAX  4/imm32
    50/push-EAX
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # . clear-stream(_test-tmp-stream)
    # . . push args
    68/push  _test-tmp-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-tmp-stream, "== abcd")
    # . . push args
    68/push  "== abcd"/imm32
    68/push  _test-tmp-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # convert-instruction(_test-tmp-stream, _test-buffered-file)
    # . . push args
    68/push  _test-buffered-file/imm32
    68/push  _test-tmp-stream/imm32
    # . . call
    e8/call  convert-instruction/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # check that the write happened as expected
    # . flush(_test-buffered-file)
    # . . push args
    68/push  _test-buffered-file/imm32
    # . . call
    e8/call  flush/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # . check-stream-equal(_test-stream, "== abcd", msg)
    # . . push args
    68/push  "F - test-convert-instruction-passes-segment-headers-through"/imm32
    68/push  "== abcd"/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  check-stream-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

test-convert-instruction-passes-empty-lines-through:
    # if a line is empty, pass it along unchanged
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # setup
    # . clear-stream(_test-stream)
    # . . push args
    68/push  _test-stream/imm32
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # . clear-stream(_test-buffered-file+4)
    # . . push args
    b8/copy-to-EAX  _test-buffered-file/imm32
    05/add-to-EAX  4/imm32
    50/push-EAX
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # . clear-stream(_test-tmp-stream)
    # . . push args
    68/push  _test-tmp-stream/imm32
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # write nothing to input
    # convert-instruction(_test-tmp-stream, _test-buffered-file)
    # . . push args
    68/push  _test-buffered-file/imm32
    68/push  _test-tmp-stream/imm32
    # . . call
    e8/call  convert-instruction/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # check that the write happened as expected
    # . flush(_test-buffered-file)
    # . . push args
    68/push  _test-buffered-file/imm32
    # . . call
    e8/call  flush/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # . check-stream-equal(_test-stream, "", msg)
    # . . push args
    68/push  "F - test-convert-instruction-passes-empty-lines-through"/imm32
    68/push  ""/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  check-stream-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

test-convert-instruction-passes-lines-with-just-whitespace-through:
    # if a line is empty, pass it along unchanged
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # setup
    # . clear-stream(_test-stream)
    # . . push args
    68/push  _test-stream/imm32
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # . clear-stream(_test-buffered-file+4)
    # . . push args
    b8/copy-to-EAX  _test-buffered-file/imm32
    05/add-to-EAX  4/imm32
    50/push-EAX
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # . clear-stream(_test-tmp-stream)
    # . . push args
    68/push  _test-tmp-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-tmp-stream, "    ")
    # . . push args
    68/push  "    "/imm32
    68/push  _test-tmp-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # convert-instruction(_test-tmp-stream, _test-buffered-file)
    # . . push args
    68/push  _test-buffered-file/imm32
    68/push  _test-tmp-stream/imm32
    # . . call
    e8/call  convert-instruction/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # check that the write happened as expected
    # . flush(_test-buffered-file)
    # . . push args
    68/push  _test-buffered-file/imm32
    # . . call
    e8/call  flush/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # . check-stream-equal(_test-stream, "    ", msg)
    # . . push args
    68/push  "F - test-convert-instruction-passes-with-just-whitespace-through"/imm32
    68/push  "    "/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  check-stream-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

test-convert-instruction-passes-labels-through:
    # if the first word ends with ':', pass along the entire line unchanged
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # setup
    # . clear-stream(_test-stream)
    # . . push args
    68/push  _test-stream/imm32
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # . clear-stream(_test-buffered-file+4)
    # . . push args
    b8/copy-to-EAX  _test-buffered-file/imm32
    05/add-to-EAX  4/imm32
    50/push-EAX
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # . clear-stream(_test-tmp-stream)
    # . . push args
    68/push  _test-tmp-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-tmp-stream, "ab: # cd")
    # . . push args
    68/push  "ab: # cd"/imm32
    68/push  _test-tmp-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # convert-instruction(_test-tmp-stream, _test-buffered-file)
    # . . push args
    68/push  _test-buffered-file/imm32
    68/push  _test-tmp-stream/imm32
    # . . call
    e8/call  convert-instruction/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # check that the write happened as expected
    # . flush(_test-buffered-file)
    # . . push args
    68/push  _test-buffered-file/imm32
    # . . call
    e8/call  flush/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # . check-stream-equal(_test-stream, "ab: # cd", msg)
    # . . push args
    68/push  "F - test-convert-instruction-passes-labels-through"/imm32
    68/push  "ab: # cd"/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  check-stream-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

# (re)compute the bounds of the next word in the line
next-word:  # line : (address stream byte), out : (address slice)
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # . save registers
    50/push-EAX
    51/push-ECX
    56/push-ESI
    57/push-EDI
    # ESI = line
    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   8/disp8         .                 # copy *(EBP+8) to ESI
    # EDI = out
    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           7/r32/EDI   0xc/disp8       .                 # copy *(EBP+12) to EDI
    # skip-chars-matching(line, ' ')
    # . . push args
    68/push  0x20/imm32/space
    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
    # . . call
    e8/call  skip-chars-matching/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # out->start = &line->data[line->read]
    8b/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           1/r32/ECX   4/disp8         .                 # copy *(ESI+4) to ECX
    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    6/base/ESI  1/index/ECX   .           0/r32/EAX   0xc/disp8       .                 # copy ESI+ECX+12 to EAX
    89/copy                         0/mod/indirect  7/rm32/EDI    .           .             .           0/r32/EAX   .               .                 # copy EAX to *EDI
    # if line->data[line->read] == '#': out->end = &line->data[line->write]), skip rest of stream and return
    # . EAX = line->data[line->read]
    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
    8a/copy-byte                    1/mod/*+disp8   4/rm32/sib    6/base/ESI  1/index/ECX   .           0/r32/AL    0xc/disp8       .                 # copy byte at *(ESI+ECX+12) to AL
    # . compare
    3d/compare-EAX-with  0x23/imm32/pound
    75/jump-if-not-equal  $next-word:not-comment/disp8
    # . out->end = &line->data[line->write]
    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           0/r32/EAX   .               .                 # copy *ESI to EAX
    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    6/base/ESI  0/index/EAX   .           0/r32/EAX   0xc/disp8       .                 # copy ESI+EAX+12 to EAX
    89/copy                         1/mod/*+disp8   7/rm32/EDI    .           .             .           0/r32/EAX   4/disp8         .                 # copy EAX to *(EDI+4)
    # . line->read = line->write
    89/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           0/r32/EAX   4/disp8         .                 # copy EAX to *(ESI+4)
    # . return
    eb/jump  $next-word:end/disp8
$next-word:not-comment:
    # otherwise skip-chars-not-matching(line, ' ')
    # . . push args
    68/push  0x20/imm32/space
    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
    # . . call
    e8/call  skip-chars-not-matching/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # out->end = &line->data[line->read]
    8b/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           1/r32/ECX   4/disp8         .                 # copy *(ESI+4) to ECX
    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    6/base/ESI  1/index/ECX   .           0/r32/EAX   0xc/disp8       .                 # copy ESI+ECX+12 to EAX
    89/copy                         1/mod/*+disp8   7/rm32/EDI    .           .             .           0/r32/EAX   4/disp8         .                 # copy EAX to *(EDI+4)
$next-word:end:
    # . restore registers
    5f/pop-to-EDI
    5e/pop-to-ESI
    59/pop-to-ECX
    58/pop-to-EAX
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

test-next-word:
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # setup
    # . clear-stream(_test-stream)
    # . . push args
    68/push  _test-stream/imm32
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # var slice/ECX = {0, 0}
    68/push  0/imm32/end
    68/push  0/imm32/start
    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
    # write(_test-stream, "  ab")
    # . . push args
    68/push  "  ab"/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # next-word(_test-stream, slice)
    # . . push args
    51/push-ECX
    68/push  _test-stream/imm32
    # . . call
    e8/call  next-word/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # check-ints-equal(slice->start - _test-stream->data, 2, msg)
    # . check-ints-equal(slice->start - _test-stream, 14, msg)
    # . . push args
    68/push  "F - test-next-word: start"/imm32
    68/push  0xe/imm32
    # . . push slice->start - _test-stream
    8b/copy                         0/mod/indirect  1/rm32/ECX    .           .             .           0/r32/EAX   .               .                 # copy *ECX to EAX
    81          5/subop/subtract    3/mod/direct    0/rm32/EAX    .           .             .           .           .               _test-stream/imm32 # subtract from EAX
    50/push-EAX
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # check-ints-equal(slice->end - _test-stream->data, 4, msg)
    # . check-ints-equal(slice->end - _test-stream, 16, msg)
    # . . push args
    68/push  "F - test-next-word: end"/imm32
    68/push  0x10/imm32
    # . . push slice->end - _test-stream
    8b/copy                         1/mod/*+disp8   1/rm32/ECX    .           .             .           0/r32/EAX   4/disp8         .                 # copy *(ECX+4) to EAX
    81          5/subop/subtract    3/mod/direct    0/rm32/EAX    .           .             .           .           .               _test-stream/imm32 # subtract from EAX
    50/push-EAX
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

test-next-word-returns-whole-comment:
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # setup
    # . clear-stream(_test-stream)
    # . . push args
    68/push  _test-stream/imm32
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # var slice/ECX = {0, 0}
    68/push  0/imm32/end
    68/push  0/imm32/start
    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
    # write(_test-stream, "  # a")
    # . . push args
    68/push  "  # a"/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # next-word(_test-stream, slice)
    # . . push args
    51/push-ECX
    68/push  _test-stream/imm32
    # . . call
    e8/call  next-word/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # check-ints-equal(slice->start - _test-stream->data, 2, msg)
    # . check-ints-equal(slice->start - _test-stream, 14, msg)
    # . . push args
    68/push  "F - test-next-word-returns-whole-comment: start"/imm32
    68/push  0xe/imm32
    # . . push slice->start - _test-stream
    8b/copy                         0/mod/indirect  1/rm32/ECX    .           .             .           0/r32/EAX   .               .                 # copy *ECX to EAX
    81          5/subop/subtract    3/mod/direct    0/rm32/EAX    .           .             .           .           .               _test-stream/imm32 # subtract from EAX
    50/push-EAX
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # check-ints-equal(slice->end - _test-stream->data, 5, msg)
    # . check-ints-equal(slice->end - _test-stream, 17, msg)
    # . . push args
    68/push  "F - test-next-word-returns-whole-comment: end"/imm32
    68/push  0x11/imm32
    # . . push slice->end - _test-stream
    8b/copy                         1/mod/*+disp8   1/rm32/ECX    .           .             .           0/r32/EAX   4/disp8         .                 # copy *(ECX+4) to EAX
    81          5/subop/subtract    3/mod/direct    0/rm32/EAX    .           .             .           .           .               _test-stream/imm32 # subtract from EAX
    50/push-EAX
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

has-metadata?:  # word : (address slice), s : (address string) -> EAX : boolean
    # pseudocode:
    #   var twig : &slice = next-token-from-slice(word->start, word->end, '/')  # skip name
    #   curr = twig->end
    #   while true:
    #     twig = next-token-from-slice(curr, word->end, '/')
    #     if twig.empty() break
    #     if slice-equal?(twig, s) return true
    #     curr = twig->end
    #   return false
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # . save registers
    51/push-ECX
    52/push-EDX
    56/push-ESI
    57/push-EDI
    # ESI = word
    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   8/disp8         .                 # copy *(EBP+8) to ESI
    # EDX = word->end
    8b/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           2/r32/EDX   4/disp8         .                 # copy *(ESI+4) to EDX
    # var twig/EDI : (address slice) = {0, 0}
    68/push  0/imm32/end
    68/push  0/imm32/start
    89/copy                         3/mod/direct    7/rm32/EDI    .           .             .           4/r32/ESP   .               .                 # copy ESP to EDI
    # next-token-from-slice(word->start, word->end, '/', twig)
    # . . push args
    57/push-EDI
    68/push  0x2f/imm32/slash
    52/push-EDX
    ff          6/subop/push        0/mod/indirect  6/rm32/ESI    .           .             .           .           .               .                 # push *ESI
    # . . call
    e8/call  next-token-from-slice/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
    # curr/ECX = twig->end
    8b/copy                         1/mod/*+disp8   7/rm32/EDI    .           .             .           1/r32/ECX   4/disp8         .                 # copy *(EDI+4) to ECX
$has-metadata?:loop:
    # next-token-from-slice(curr, word->end, '/', twig)
    # . . push args
    57/push-EDI
    68/push  0x2f/imm32/slash
    52/push-EDX
    51/push-ECX
    # . . call
    e8/call  next-token-from-slice/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
    # if slice-empty?(twig) return false
    # . EAX = slice-empty?(twig)
    # . . push args
    57/push-EDI
    # . . call
    e8/call  slice-empty?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # . if (EAX != 0) return false
    81          7/subop/compare     3/mod/direct    0/rm32/EAX    .           .             .           .           .               0/imm32           # compare EAX
    75/compare-if-not-equal  $has-metadata?:false/disp8
    # if slice-equal?(twig, s) return true
    # . EAX = slice-equal?(twig, s)
    # . . push args
    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
    57/push-EDI
    # . . call
    e8/call  slice-equal?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # . if (EAX != 0) return true
    81          7/subop/compare     3/mod/direct    0/rm32/EAX    .           .             .           .           .               0/imm32           # compare EAX
    75/compare-if-not-equal  $has-metadata?:true/disp8
    # curr = twig->end
    8b/copy                         1/mod/*+disp8   7/rm32/EDI    .           .             .           1/r32/ECX   4/disp8         .                 # copy *(EDI+4) to ECX
    eb/jump  $has-metadata?:loop/disp8
$has-metadata?:true:
    b8/copy-to-EAX  1/imm32/true
    eb/jump  $has-metadata?:end/disp8
$has-metadata?:false:
    b8/copy-to-EAX  0/imm32/false
$has-metadata?:end:
    # . reclaim locals
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # . restore registers
    5f/pop-to-EDI
    5e/pop-to-ESI
    5a/pop-to-EDX
    59/pop-to-ECX
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

test-has-metadata-true:
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # (EAX..ECX) = "ab/c"
    b8/copy-to-EAX  "ab/c"/imm32
    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
    05/add-to-EAX  4/imm32
    # var in/ESI : (address slice) = {EAX, ECX}
    51/push-ECX
    50/push-EAX
    89/copy                         3/mod/direct    6/rm32/ESI    .           .             .           4/r32/ESP   .               .                 # copy ESP to ESI
    # EAX = has-metadata?(ESI, "c")
    # . . push args
    68/push  "c"/imm32
    56/push-ESI
    # . . call
    e8/call  has-metadata?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x8/imm32         # add to ESP
    # check-ints-equal(EAX, 1, msg)
    # . . push args
    68/push  "F - test-has-metadata-true"/imm32
    68/push  1/imm32/true
    50/push-EAX
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

test-has-metadata-false:
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # (EAX..ECX) = "ab/c"
    b8/copy-to-EAX  "ab/c"/imm32
    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
    05/add-to-EAX  4/imm32
    # var in/ESI : (address slice) = {EAX, ECX}
    51/push-ECX
    50/push-EAX
    89/copy                         3/mod/direct    6/rm32/ESI    .           .             .           4/r32/ESP   .               .                 # copy ESP to ESI
    # EAX = has-metadata?(ESI, "c")
    # . . push args
    68/push  "d"/imm32
    56/push-ESI
    # . . call
    e8/call  has-metadata?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x8/imm32         # add to ESP
    # check-ints-equal(EAX, 0, msg)
    # . . push args
    68/push  "F - test-has-metadata-false"/imm32
    68/push  0/imm32/false
    50/push-EAX
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

test-has-metadata-ignore-name:
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # (EAX..ECX) = "a/b"
    b8/copy-to-EAX  "a/b"/imm32
    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
    05/add-to-EAX  4/imm32
    # var in/ESI : (address slice) = {EAX, ECX}
    51/push-ECX
    50/push-EAX
    89/copy                         3/mod/direct    6/rm32/ESI    .           .             .           4/r32/ESP   .               .                 # copy ESP to ESI
    # EAX = has-metadata?(ESI, "a")
    # . . push args
    68/push  "a"/imm32
    56/push-ESI
    # . . call
    e8/call  has-metadata?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x8/imm32         # add to ESP
    # check-ints-equal(EAX, 0, msg)
    # . . push args
    68/push  "F - test-has-metadata-ignore-name"/imm32
    68/push  0/imm32/false
    50/push-EAX
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

test-has-metadata-multiple-true:
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # (EAX..ECX) = "a/b/c"
    b8/copy-to-EAX  "a/b/c"/imm32
    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
    05/add-to-EAX  4/imm32
    # var in/ESI : (address slice) = {EAX, ECX}
    51/push-ECX
    50/push-EAX
    89/copy                         3/mod/direct    6/rm32/ESI    .           .             .           4/r32/ESP   .               .                 # copy ESP to ESI
    # EAX = has-metadata?(ESI, "c")
    # . . push args
    68/push  "c"/imm32
    56/push-ESI
    # . . call
    e8/call  has-metadata?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x8/imm32         # add to ESP
    # check-ints-equal(EAX, 1, msg)
    # . . push args
    68/push  "F - test-has-metadata-multiple-true"/imm32
    68/push  1/imm32/true
    50/push-EAX
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

test-has-metadata-multiple-false:
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # (EAX..ECX) = "a/b/c"
    b8/copy-to-EAX  "a/b/c"/imm32
    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
    05/add-to-EAX  4/imm32
    # var in/ESI : (address slice) = {EAX, ECX}
    51/push-ECX
    50/push-EAX
    89/copy                         3/mod/direct    6/rm32/ESI    .           .             .           4/r32/ESP   .               .                 # copy ESP to ESI
    # EAX = has-metadata?(ESI, "d")
    # . . push args
    68/push  "d"/imm32
    56/push-ESI
    # . . call
    e8/call  has-metadata?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x8/imm32         # add to ESP
    # check-ints-equal(EAX, 0, msg)
    # . . push args
    68/push  "F - test-has-metadata-multiple-false"/imm32
    68/push  0/imm32/false
    50/push-EAX
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

# if the name of 'word' is all hex digits, parse and print its value in 'width' bytes of hex, least significant first
# otherwise just print the entire word
emit:  # out : (address buffered-file), word : (address slice), width : int
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # . save registers
    50/push-EAX
    56/push-ESI
    57/push-EDI
    # ESI = word
    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   0xc/disp8       .                 # copy *(EBP+12) to ESI
    # var name/EDI : (address slice) = {0, 0}
    68/push  0/imm32/end
    68/push  0/imm32/start
    89/copy                         3/mod/direct    7/rm32/EDI    .           .             .           4/r32/ESP   .               .                 # copy ESP to EDI
    # name = next-token-from-slice(word->start, word->end, '/')
    # . . push args
    57/push-EDI
    68/push  0x2f/imm32/slash
    ff          6/subop/push        1/mod/*+disp8   6/rm32/ESI    .           .             .           .           4/disp8         .                 # push *(ESI+4)
    ff          6/subop/push        0/mod/indirect  6/rm32/ESI    .           .             .           .           .               .                 # push *ESI
    # . . call
    e8/call  next-token-from-slice/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
    # if !is-hex-int?(name) write-slice(out, word) and return
    # . is-hex-int?(name)
    # . . push args
    57/push-EDI
    # . . call
    e8/call  is-hex-int?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # . if EAX == 0
    81          7/subop/compare     3/mod/direct    0/rm32/EAX    .           .             .           .           .               0/imm32           # compare EAX
    75/jump-if-not-equal  $emit:hex-int/disp8
    # . write-slice(out, word)
    # . . push args
    56/push-ESI
    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
    # . . call
    e8/call  write-slice/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # . return
    eb/jump  $emit:end/disp8
    # otherwise emit-hex(out, parse-hex-int(name), width)
$emit:hex-int:
    # . n/EAX = parse-hex-int(name)
    # . . push args
    57/push-EDI
    # . . call
    e8/call  parse-hex-int/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # . emit-hex(out, n, width)
    # . . push args
    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x10/disp8      .                 # push *(EBP+16)
    50/push-EAX
    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
    # . . call
    e8/call  emit-hex/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
$emit:end:
    # . reclaim locals
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # . restore registers
    5f/pop-to-EDI
    5e/pop-to-ESI
    58/pop-to-EAX
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

test-emit-number:
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # setup
    # . clear-stream(_test-stream)
    # . . push args
    68/push  _test-stream/imm32
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # . clear-stream(_test-buffered-file+4)
    # . . push args
    b8/copy-to-EAX  _test-buffered-file/imm32
    05/add-to-EAX  4/imm32
    50/push-EAX
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # var slice/ECX = "-2"
    68/push  _test-slice-negative-two-end/imm32/end
    68/push  _test-slice-negative-two/imm32/start
    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
    # emit(_test-buffered-file, slice, 2)
    # . . push args
    68/push  2/imm32
    51/push-ECX
    68/push  _test-buffered-file/imm32
    # . . call
    e8/call  emit/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # flush(_test-buffered-file)
    # . . push args
    68/push  _test-buffered-file/imm32
    # . . call
    e8/call  flush/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # check(_test-stream->data == 'fe ff ')
    # . check-ints-equal(_test-stream->data[0..3], 'fe f', msg)
    # . . push args
    68/push  "F - test-emit-number/1"/imm32
    68/push  0x66206566/imm32
    # . . push *_test-stream->data
    b8/copy-to-EAX  _test-stream/imm32
    ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           0xc/disp8       .                 # push *(EAX+12)
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # . check-ints-equal(_test-stream->data[4..7], 'f ', msg)
    # . . push args
    68/push  "F - test-emit-number/2"/imm32
    68/push  0x2066/imm32
    # . . push *_test-stream->data
    b8/copy-to-EAX  _test-stream/imm32
    ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           0x10/disp8      .                 # push *(EAX+16)
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

test-emit-number-with-metadata:
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # setup
    # . clear-stream(_test-stream)
    # . . push args
    68/push  _test-stream/imm32
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # . clear-stream(_test-buffered-file+4)
    # . . push args
    b8/copy-to-EAX  _test-buffered-file/imm32
    05/add-to-EAX  4/imm32
    50/push-EAX
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # var slice/ECX = "-2/foo"
    68/push  _test-slice-negative-two-metadata-end/imm32/end
    68/push  _test-slice-negative-two/imm32/start
    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
    # emit(_test-buffered-file, slice, 2)
    # . . push args
    68/push  2/imm32
    51/push-ECX
    68/push  _test-buffered-file/imm32
    # . . call
    e8/call  emit/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # flush(_test-buffered-file)
    # . . push args
    68/push  _test-buffered-file/imm32
    # . . call
    e8/call  flush/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # the '/foo' will have no impact on the output
    # check(_test-stream->data == 'fe ff ')
    # . check-ints-equal(_test-stream->data[0..3], 'fe f', msg)
    # . . push args
    68/push  "F - test-emit-number-with-metadata/1"/imm32
    68/push  0x66206566/imm32
    # . . push *_test-stream->data
    b8/copy-to-EAX  _test-stream/imm32
    ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           0xc/disp8       .                 # push *(EAX+12)
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # . check-ints-equal(_test-stream->data[4..7], 'f ', msg)
    # . . push args
    68/push  "F - test-emit-number-with-metadata/2"/imm32
    68/push  0x2066/imm32
    # . . push *_test-stream->data
    b8/copy-to-EAX  _test-stream/imm32
    ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           0x10/disp8      .                 # push *(EAX+16)
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

test-emit-non-number:
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # setup
    # . clear-stream(_test-stream)
    # . . push args
    68/push  _test-stream/imm32
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # . clear-stream(_test-buffered-file+4)
    # . . push args
    b8/copy-to-EAX  _test-buffered-file/imm32
    05/add-to-EAX  4/imm32
    50/push-EAX
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # var slice/ECX = "xyz"
    68/push  _test-slice-non-number-word-end/imm32/end
    68/push  _test-slice-non-number-word/imm32/start
    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
    # emit(_test-buffered-file, slice, 2)
    # . . push args
    68/push  2/imm32
    51/push-ECX
    68/push  _test-buffered-file/imm32
    # . . call
    e8/call  emit/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # flush(_test-buffered-file)
    # . . push args
    68/push  _test-buffered-file/imm32
    # . . call
    e8/call  flush/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # check(_test-stream->data == 'xyz')
    # . check-ints-equal(_test-stream->data[0..3], 'xyz', msg)
    # . . push args
    68/push  "F - test-emit-non-number"/imm32
    68/push  0x7a7978/imm32
    # . . push *_test-stream->data
    b8/copy-to-EAX  _test-stream/imm32
    ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           0xc/disp8       .                 # push *(EAX+12)
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

test-emit-non-number-with-metadata:
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # setup
    # . clear-stream(_test-stream)
    # . . push args
    68/push  _test-stream/imm32
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # . clear-stream(_test-buffered-file+4)
    # . . push args
    b8/copy-to-EAX  _test-buffered-file/imm32
    05/add-to-EAX  4/imm32
    50/push-EAX
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # var slice/ECX = "xyz/"
    68/push  _test-slice-non-number-word-metadata-end/imm32/end
    68/push  _test-slice-non-number-word/imm32/start
    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
    # emit(_test-buffered-file, slice, 2)
    # . . push args
    68/push  2/imm32
    51/push-ECX
    68/push  _test-buffered-file/imm32
    # . . call
    e8/call  emit/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # flush(_test-buffered-file)
    # . . push args
    68/push  _test-buffered-file/imm32
    # . . call
    e8/call  flush/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # check(_test-stream->data == 'xyz/')
    # . check-ints-equal(_test-stream->data[0..3], 'xyz/', msg)
    # . . push args
    68/push  "F - test-emit-non-number-with-metadata"/imm32
    68/push  0x2f7a7978/imm32
    # . . push *_test-stream->data
    b8/copy-to-EAX  _test-stream/imm32
    ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           0xc/disp8       .                 # push *(EAX+12)
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

# print 'n' in hex in 'width' bytes in lower-endian order, with a space after every byte
emit-hex:  # out : (address buffered-file), n : int, width : int
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # . save registers
    50/push-EAX
    51/push-ECX
    52/push-EDX
    53/push-EBX
    57/push-EDI
    # EDI = out
    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           7/r32/EDI   8/disp8         .                 # copy *(EBP+8) to EDI
    # EBX = n
    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           3/r32/EBX   0xc/disp8       .                 # copy *(EBP+12) to EBX
    # EDX = width
    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           2/r32/EDX   0x10/disp8      .                 # copy *(EBP+16) to EDX
    # var curr/ECX = 0
    31/xor                          3/mod/direct    1/rm32/ECX    .           .             .           1/r32/ECX   .               .                 # clear ECX
$emit-hex:loop:
    # if (curr >= width) break
    39/compare                      3/mod/direct    1/rm32/ECX    .           .             .           2/r32/EDX   .               .                 # compare ECX and EDX
    7d/jump-if-greater-or-equal  $emit-hex:end/disp8
    # print-byte(out, EBX)
    # . . push args
    53/push-EBX
    57/push-EDI
    # . . call
    e8/call  print-byte/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # write-byte(out, ' ')
    # . . push args
    68/push  0x20/imm32/space
    57/push-EDI
    # . . call
    e8/call  write-byte/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # EBX = EBX >> 8
    c1/shift    5/subop/logic-right 3/mod/direct    3/rm32/EBX    .           .             .           .           .               8/imm8            # shift EBX right by 8 bits, while padding zeroes
    # ++curr
    41/increment-ECX
    eb/jump  $emit-hex:loop/disp8
$emit-hex:end:
    # . restore registers
    5f/pop-to-EDI
    5b/pop-to-EBX
    5a/pop-to-EAX
    59/pop-to-ECX
    58/pop-to-EAX
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

test-emit-hex-single-byte:
    # setup
    # . clear-stream(_test-stream)
    # . . push args
    68/push  _test-stream/imm32
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # . clear-stream(_test-buffered-file+4)
    # . . push args
    b8/copy-to-EAX  _test-buffered-file/imm32
    05/add-to-EAX  4/imm32
    50/push-EAX
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # emit-hex(_test-buffered-file, 0xab, 1)
    # . . push args
    68/push  1/imm32
    68/push  0xab/imm32
    68/push  _test-buffered-file/imm32
    # . . call
    e8/call  emit-hex/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # flush(_test-buffered-file)
    # . . push args
    68/push  _test-buffered-file/imm32
    # . . call
    e8/call  flush/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # check-ints-equal(*_test-stream->data, 'ab ', msg)
    # . . push args
    68/push  "F - test-emit-hex-single-byte"/imm32
    68/push  0x206261/imm32
    # . . push *_test-stream->data
    b8/copy-to-EAX  _test-stream/imm32
    ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           0xc/disp8       .                 # push *(EAX+12)
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # . end
    c3/return

test-emit-hex-multiple-byte:
    # setup
    # . clear-stream(_test-stream)
    # . . push args
    68/push  _test-stream/imm32
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # . clear-stream(_test-buffered-file+4)
    # . . push args
    b8/copy-to-EAX  _test-buffered-file/imm32
    05/add-to-EAX  4/imm32
    50/push-EAX
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # emit-hex(_test-buffered-file, 0x1234, 2)
    # . . push args
    68/push  2/imm32
    68/push  0x1234/imm32
    68/push  _test-buffered-file/imm32
    # . . call
    e8/call  emit-hex/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # flush(_test-buffered-file)
    # . . push args
    68/push  _test-buffered-file/imm32
    # . . call
    e8/call  flush/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # check(_test-stream->data == '34 12 ')
    # . check-ints-equal(_test-stream->data[0..3], '34 1', msg)
    # . . push args
    68/push  "F - test-emit-hex-multiple-byte/1"/imm32
    68/push  0x31203433/imm32
    # . . push *_test-stream->data
    b8/copy-to-EAX  _test-stream/imm32
    ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           0xc/disp8       .                 # push *(EAX+12)
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # . check-ints-equal(_test-stream->data[4..7], '2 ', msg)
    # . . push args
    68/push  "F - test-emit-hex-multiple-byte/2"/imm32
    68/push  0x2032/imm32
    # . . push *_test-stream->data
    b8/copy-to-EAX  _test-stream/imm32
    ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           0x10/disp8      .                 # push *(EAX+16)
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # . end
    c3/return

test-emit-hex-zero-pad:
    # setup
    # . clear-stream(_test-stream)
    # . . push args
    68/push  _test-stream/imm32
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # . clear-stream(_test-buffered-file+4)
    # . . push args
    b8/copy-to-EAX  _test-buffered-file/imm32
    05/add-to-EAX  4/imm32
    50/push-EAX
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # emit-hex(_test-buffered-file, 0xab, 2)
    # . . push args
    68/push  2/imm32
    68/push  0xab/imm32
    68/push  _test-buffered-file/imm32
    # . . call
    e8/call  emit-hex/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # flush(_test-buffered-file)
    # . . push args
    68/push  _test-buffered-file/imm32
    # . . call
    e8/call  flush/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # check(_test-stream->data == '00 ab')
    # . check-ints-equal(*_test-stream->data, 'ab 0', msg)
    # . . push args
    68/push  "F - test-emit-hex-zero-pad/1"/imm32
    68/push  0x30206261/imm32
    # . . push *_test-stream->data
    b8/copy-to-EAX  _test-stream/imm32
    ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           0xc/disp8       .                 # push *(EAX+12)
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # . check-ints-equal(*_test-stream->data[1], '0 ', msg)
    # . . push args
    68/push  "F - test-emit-hex-zero-pad/2"/imm32
    68/push  0x2030/imm32
    # . . push *_test-stream->data
    b8/copy-to-EAX  _test-stream/imm32
    ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           0x10/disp8      .                 # push *(EAX+16)
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # . end
    c3/return

test-emit-hex-negative:
    # setup
    # . clear-stream(_test-stream)
    # . . push args
    68/push  _test-stream/imm32
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # . clear-stream(_test-buffered-file+4)
    # . . push args
    b8/copy-to-EAX  _test-buffered-file/imm32
    05/add-to-EAX  4/imm32
    50/push-EAX
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # emit-hex(_test-buffered-file, -1, 2)
    # . . push args
    68/push  2/imm32
    68/push  -1/imm32
    68/push  _test-buffered-file/imm32
    # . . call
    e8/call  emit-hex/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # flush(_test-buffered-file)
    # . . push args
    68/push  _test-buffered-file/imm32
    # . . call
    e8/call  flush/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # check(_test-stream->data == 'ff ff ')
    # . check-ints-equal(_test-stream->data[0..3], 'ff f', msg)
    # . . push args
    68/push  "F - test-emit-hex-negative/1"/imm32
    68/push  0x66206666/imm32
    # . . push *_test-stream->data
    b8/copy-to-EAX  _test-stream/imm32
    ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           0xc/disp8       .                 # push *(EAX+12)
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # . check-ints-equal(_test-stream->data[4..7], 'f ', msg)
    # . . push args
    68/push  "F - test-emit-hex-negative/2"/imm32
    68/push  0x2066/imm32
    # . . push *_test-stream->data
    b8/copy-to-EAX  _test-stream/imm32
    ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           0x10/disp8      .                 # push *(EAX+16)
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # . end
    c3/return

== data

_test-slice-negative-two:
    2d/- 32/2
_test-slice-negative-two-end:
    2f/slash 66/f 6f/o 6f/o
_test-slice-negative-two-metadata-end:

_test-slice-non-number-word:
    78/x 79/y 7a/z
_test-slice-non-number-word-end:
    2f/slash
_test-slice-non-number-word-metadata-end:

# . . vim:nowrap:textwidth=0