path: root/subx/apps/subx-common.subx

# some common helpers shared by phases of the SubX converter

== 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

# 'table' is a stream of (key, value) rows
# keys are always strings (addresses; size 4 bytes)
# values may be any type, but rows (key+value) always occupy 'row-size' bytes
# scan 'table' for a row with a key 'key' and return the address of the corresponding value
# if no row is found, save 'key' to the next available row
# if there are no rows free, abort
# return the address of the value
# Beware: assume keys are immutable; they're inserted by reference
# TODO: pass in an allocation descriptor
get-or-insert:  # table : (address stream {string, _}), key : (address string), row-size : int -> EAX : (address _)
    # pseudocode:
    #   curr = table->data
    #   max = &table->data[table->write]
    #   while curr < max
    #     if string-equal?(key, *curr)
    #       return curr+4
    #     curr += row-size
    #   if table->write >= table->length
    #     abort
    #   *max = key
    #   table->write += row-size
    #   return max+4
    #
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # . save registers
    51/push-ECX
    52/push-EDX
    56/push-ESI
    # ESI = table
    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   8/disp8         .                 # copy *(EBP+8) to ESI
    # curr/ECX = table->data
    8d/copy-address                 1/mod/*+disp8   6/rm32/ESI    .           .             .           1/r32/ECX   0xc/disp8       .                 # copy ESI+12 to ECX
    # max/EDX = table->data + table->write
    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           2/r32/EDX   .               .                 # copy *ESI to EDX
    8d/copy-address                 0/mod/indirect  4/rm32/sib    1/base/ECX  2/index/EDX   .           2/r32/EDX   .               .                 # copy ECX+EDX to EDX
$get-or-insert:search-loop:
    # if (curr >= max) break
    39/compare                      3/mod/direct    1/rm32/ECX    .           .             .           2/r32/EDX   .               .                 # compare ECX with EDX
    7d/jump-if-greater-or-equal  $get-or-insert:not-found/disp8
    # if (string-equal?(key, *curr)) return curr+4
    # . EAX = string-equal?(key, *curr)
    # . . push args
    ff          6/subop/push        0/mod/indirect  1/rm32/ECX    .           .             .           .           .               .                 # push *ECX
    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
    # . . call
    e8/call  string-equal?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # . if (EAX != 0) return EAX = curr+4
    3d/compare-EAX-and  0/imm32
    74/jump-if-equal  $get-or-insert:mismatch/disp8
    8d/copy-address                 1/mod/*+disp8   1/rm32/ECX    .           .             .           0/r32/EAX   4/disp8         .                 # copy ECX+4 to EAX
    eb/jump  $get-or-insert:end/disp8
$get-or-insert:mismatch:
    # curr += row-size
    03/add                          1/mod/*+disp8   5/rm32/EBP    .           .             .           1/r32/ECX   0x10/disp8      .                 # add *(EBP+16) to ECX
    # loop
    eb/jump  $get-or-insert:search-loop/disp8
$get-or-insert:not-found:
    # result/EAX = 0
    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
    # if (table->write >= table->length) abort
    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           1/r32/ECX   .               .                 # copy *ESI to ECX
    3b/compare                      1/mod/*+disp8   6/rm32/ESI    .           .             .           1/r32/ECX   8/disp8         .                 # compare ECX with *(ESI+8)
    73/jump-if-greater-or-equal-unsigned  $get-or-insert:abort/disp8
    # *max = key
    # . EAX = key
    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           0/r32/EAX   0xc/disp8       .                 # copy *(EBP+12) to EAX
    # . *max = EAX
    89/copy                         0/mod/indirect  2/rm32/EDX    .           .             .           0/r32/EAX   .               .                 # copy EAX to *EDX
    # table->write += row-size
    # . EAX = row-size
    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           0/r32/EAX   0x10/disp8      .                 # copy *(EBP+16) to EAX
    # . table->write += EAX
    01/add                          0/mod/indirect  6/rm32/ESI    .           .             .           0/r32/EAX   .               .                 # add EAX to *ESI
    # return max+4
    # . EAX = max
    89/copy                         3/mod/direct    0/rm32/EAX    .           .             .           2/r32/EDX   .               .                 # copy EDX to EAX
    # . EAX += 4
    05/add-to-EAX  4/imm32
$get-or-insert:end:
    # . restore registers
    5e/pop-to-ESI
    5a/pop-to-EDX
    59/pop-to-ECX
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

$get-or-insert:abort:
    # . _write(2/stderr, error)
    # . . push args
    68/push  "get-or-insert: too many segments"/imm32
    68/push  2/imm32/stderr
    # . . call
    e8/call  _write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # . syscall(exit, 1)
    bb/copy-to-EBX  1/imm32
    b8/copy-to-EAX  1/imm32/exit
    cd/syscall  0x80/imm8
    # never gets here

test-get-or-insert:
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # var table/ECX : (address stream {string, number}) = stream(2 rows * 8 bytes)
    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # subtract from ESP
    68/push  0x10/imm32/length
    68/push  0/imm32/read
    68/push  0/imm32/write
    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
$test-get-or-insert:first-call:
    # - start with an empty table, insert one key, verify that it was inserted
    # EAX = get-or-insert(table, "code", 8 bytes per row)
    # . . push args
    68/push  8/imm32/row-size
    68/push  "code"/imm32
    51/push-ECX
    # . . call
    e8/call  get-or-insert/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # check-ints-equal(EAX - table->data, 4, msg)  # first row's value slot returned
    # . check-ints-equal(EAX - table, 16, msg)
    # . . push args
    68/push  "F - test-get-or-insert/0"/imm32
    68/push  0x10/imm32
    29/subtract                     3/mod/direct    0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # subtract ECX from EAX
    50/push-EAX
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
$test-get-or-insert:check2:
    # check-ints-equal(table->write, row-size = 8, msg)
    # . . push args
    68/push  "F - test-get-or-insert/1"/imm32
    68/push  8/imm32/row-size
    ff          6/subop/push        0/mod/indirect  1/rm32/ECX    .           .             .           .           .               .                 # push *ECX
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # check-string-equal(*table->data, "code", msg)
    # . . push args
    68/push  "F - test-get-or-insert/2"/imm32
    68/push  "code"/imm32
    ff          6/subop/push        1/mod/*+disp8   1/rm32/ECX    .           .             .           .           0xc/disp8       .                 # push *(ECX+12)
    # . . call
    e8/call  check-string-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
$test-get-or-insert:second-call:
    # - insert the same key again, verify that it was reused
    # EAX = get-or-insert(table, "code", 8 bytes per row)
    # . . push args
    68/push  8/imm32/row-size
    68/push  "code"/imm32
    51/push-ECX
    # . . call
    e8/call  get-or-insert/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # check-ints-equal(EAX - table->data, 4, msg)
    # . check-ints-equal(EAX - table, 16, msg)
    # . . push args
    68/push  "F - test-get-or-insert/3"/imm32
    68/push  0x10/imm32
    29/subtract                     3/mod/direct    0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # subtract ECX from EAX
    50/push-EAX
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # no new row inserted
    # . check-ints-equal(table->write, row-size = 8, msg)
    # . . push args
    68/push  "F - test-get-or-insert/4"/imm32
    68/push  8/imm32/row-size
    ff          6/subop/push        0/mod/indirect  1/rm32/ECX    .           .             .           .           .               .                 # push *ECX
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # check-string-equal(*table->data, "code", msg)
    # . . push args
    68/push  "F - test-get-or-insert/5"/imm32
    68/push  "code"/imm32
    ff          6/subop/push        1/mod/*+disp8   1/rm32/ECX    .           .             .           .           0xc/disp8       .                 # push *(ECX+12)
    # . . call
    e8/call  check-string-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
$test-get-or-insert:third-call:
    # - insert a new key, verify that it was inserted
    # EAX = get-or-insert(table, "data", 8 bytes per row)
    # . . push args
    68/push  8/imm32/row-size
    68/push  "data"/imm32
    51/push-ECX
    # . . call
    e8/call  get-or-insert/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # table gets a new row
    # check-ints-equal(EAX - table->data, 12, msg)  # second row's value slot returned
    # . check-ints-equal(EAX - table, 24, msg)
    # . . push args
    68/push  "F - test-get-or-insert/6"/imm32
    68/push  0x18/imm32
    29/subtract                     3/mod/direct    0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # subtract ECX from EAX
    50/push-EAX
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # check-ints-equal(table->write, 2 rows = 16, msg)
    # . . push args
    68/push  "F - test-get-or-insert/7"/imm32
    68/push  0x10/imm32/two-rows
    ff          6/subop/push        0/mod/indirect  1/rm32/ECX    .           .             .           .           .               .                 # push *ECX
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # check-string-equal(*table->data+8, "data", msg)
    # check-string-equal(*(table+20), "data", msg)
    # . . push args
    68/push  "F - test-get-or-insert/8"/imm32
    68/push  "data"/imm32
    ff          6/subop/push        1/mod/*+disp8   1/rm32/ECX    .           .             .           .           0x14/disp8      .                 # push *(ECX+20)
    # . . call
    e8/call  check-string-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
$test-get-or-insert:end:
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

# 'table' is a stream of (key, value) rows
# keys are always strings (addresses; size 4 bytes)
# values may be any type, but rows (key+value) always occupy 'row-size' bytes
# scan 'table' for a row with a key 'key' and return the address of the corresponding value
# if no row is found, save 'key' in the next available row
# if there are no rows free, abort
# TODO: pass in an allocation descriptor
get-or-insert-slice:  # table : (address stream {string, _}), key : (address slice), row-size : int -> EAX : (address _)
    # pseudocode:
    #   curr = table->data
    #   max = &table->data[table->write]
    #   while curr < max
    #     if slice-equal?(key, *curr)
    #       return curr+4
    #     curr += row-size
    #   if table->write >= table->length
    #     abort
    #   *max = slice-to-string(Heap, key)
    #   table->write += row-size
    #   return max+4
    #
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # . save registers
    51/push-ECX
    52/push-EDX
    56/push-ESI
    # ESI = table
    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   8/disp8         .                 # copy *(EBP+8) to ESI
    # curr/ECX = table->data
    8d/copy-address                 1/mod/*+disp8   6/rm32/ESI    .           .             .           1/r32/ECX   0xc/disp8       .                 # copy ESI+12 to ECX
    # max/EDX = table->data + table->write
    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           2/r32/EDX   .               .                 # copy *ESI to EDX
    8d/copy-address                 0/mod/indirect  4/rm32/sib    1/base/ECX  2/index/EDX   .           2/r32/EDX   .               .                 # copy ECX+EDX to EDX
$get-or-insert-slice:search-loop:
    # if (curr >= max) break
    39/compare                      3/mod/direct    1/rm32/ECX    .           .             .           2/r32/EDX   .               .                 # compare ECX with EDX
    73/jump-if-greater-or-equal-unsigned  $get-or-insert-slice:not-found/disp8
    # if (slice-equal?(key, *curr)) return curr+4
    # . EAX = slice-equal?(key, *curr)
    # . . push args
    ff          6/subop/push        0/mod/indirect  1/rm32/ECX    .           .             .           .           .               .                 # push *ECX
    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
    # . . call
    e8/call  slice-equal?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # . if (EAX != 0) return EAX = curr+4
    3d/compare-EAX-and  0/imm32
    74/jump-if-equal  $get-or-insert-slice:mismatch/disp8
    8d/copy-address                 1/mod/*+disp8   1/rm32/ECX    .           .             .           0/r32/EAX   4/disp8         .                 # copy ECX+4 to EAX
    eb/jump  $get-or-insert-slice:end/disp8
$get-or-insert-slice:mismatch:
    # curr += row-size
    03/add                          1/mod/*+disp8   5/rm32/EBP    .           .             .           1/r32/ECX   0x10/disp8      .                 # add *(EBP+16) to ECX
    # loop
    eb/jump  $get-or-insert-slice:search-loop/disp8
$get-or-insert-slice:not-found:
    # result/EAX = 0
    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
    # if (table->write >= table->length) abort
    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           1/r32/ECX   .               .                 # copy *ESI to ECX
    3b/compare                      1/mod/*+disp8   6/rm32/ESI    .           .             .           1/r32/ECX   8/disp8         .                 # compare ECX with *(ESI+8)
    7d/jump-if-greater-or-equal  $get-or-insert-slice:abort/disp8
    # *max = slice-to-string(Heap, key)
    # . EAX = slice-to-string(Heap, key)
    # . . push args
    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
    68/push  Heap/imm32
    # . . call
    e8/call  slice-to-string/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # . *max = EAX
    89/copy                         0/mod/indirect  2/rm32/EDX    .           .             .           0/r32/EAX   .               .                 # copy EAX to *EDX
    # table->write += row-size
    # . EAX = row-size
    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           0/r32/EAX   0x10/disp8      .                 # copy *(EBP+16) to EAX
    # . table->write += EAX
    01/add                          0/mod/indirect  6/rm32/ESI    .           .             .           0/r32/EAX   .               .                 # add EAX to *ESI
    # return max+4
    # . EAX = max
    89/copy                         3/mod/direct    0/rm32/EAX    .           .             .           2/r32/EDX   .               .                 # copy EDX to EAX
    # . EAX += 4
    05/add-to-EAX  4/imm32
$get-or-insert-slice:end:
    # . restore registers
    5e/pop-to-ESI
    5a/pop-to-EDX
    59/pop-to-ECX
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

$get-or-insert-slice:abort:
    # . _write(2/stderr, error)
    # . . push args
    68/push  "get-or-insert-slice: too many segments"/imm32
    68/push  2/imm32/stderr
    # . . call
    e8/call  _write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # . syscall(exit, 1)
    bb/copy-to-EBX  1/imm32
    b8/copy-to-EAX  1/imm32/exit
    cd/syscall  0x80/imm8
    # never gets here

test-get-or-insert-slice:
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # var table/ECX : (address stream {string, number}) = stream(2 rows * 8 bytes)
    81          5/subop/subtract    3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # subtract from ESP
    68/push  0x10/imm32/length
    68/push  0/imm32/read
    68/push  0/imm32/write
    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
    # (EAX..EDX) = "code"
    b8/copy-to-EAX  "code"/imm32
    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           2/r32/EDX   .               .                 # copy *EAX to EDX
    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  2/index/EDX   .           2/r32/EDX   4/disp8         .                 # copy EAX+EDX+4 to EDX
    05/add-to-EAX  4/imm32
    # var slice/EDX = {EAX, EDX}
    52/push-EDX
    50/push-EAX
    89/copy                         3/mod/direct    2/rm32/EDX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EDX
$test-get-or-insert-slice:first-call:
    # - start with an empty table, insert one key, verify that it was inserted
    # EAX = get-or-insert-slice(table, "code" slice, 8 bytes per row)
    # . . push args
    68/push  8/imm32/row-size
    52/push-EDX
    51/push-ECX
    # . . call
    e8/call  get-or-insert-slice/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # check-ints-equal(EAX - table->data, 4, msg)  # first row's value slot returned
    # . check-ints-equal(EAX - table, 16, msg)
    # . . push args
    68/push  "F - test-get-or-insert-slice/0"/imm32
    68/push  0x10/imm32
    29/subtract                     3/mod/direct    0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # subtract ECX from EAX
    50/push-EAX
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
$test-get-or-insert-slice:check2:
    # check-ints-equal(table->write, row-size = 8, msg)
    # . . push args
    68/push  "F - test-get-or-insert-slice/1"/imm32
    68/push  8/imm32/row-size
    ff          6/subop/push        0/mod/indirect  1/rm32/ECX    .           .             .           .           .               .                 # push *ECX
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # check-string-equal(*table->data, "code", msg)
    # . . push args
    68/push  "F - test-get-or-insert-slice/2"/imm32
    68/push  "code"/imm32
    ff          6/subop/push        1/mod/*+disp8   1/rm32/ECX    .           .             .           .           0xc/disp8       .                 # push *(ECX+12)
    # . . call
    e8/call  check-string-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
$test-get-or-insert-slice:second-call:
    # - insert the same key again, verify that it was reused
    # EAX = get-or-insert-slice(table, "code" slice, 8 bytes per row)
    # . . push args
    68/push  8/imm32/row-size
    52/push-EDX
    51/push-ECX
    # . . call
    e8/call  get-or-insert-slice/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # check-ints-equal(EAX - table->data, 4, msg)
    # . check-ints-equal(EAX - table, 16, msg)
    # . . push args
    68/push  "F - test-get-or-insert-slice/3"/imm32
    68/push  0x10/imm32
    29/subtract                     3/mod/direct    0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # subtract ECX from EAX
    50/push-EAX
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # no new row inserted
    # . check-ints-equal(table->write, row-size = 8, msg)
    # . . push args
    68/push  "F - test-get-or-insert-slice/4"/imm32
    68/push  8/imm32/row-size
    ff          6/subop/push        0/mod/indirect  1/rm32/ECX    .           .             .           .           .               .                 # push *ECX
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # check-string-equal(*table->data, "code", msg)
    # . . push args
    68/push  "F - test-get-or-insert-slice/5"/imm32
    68/push  "code"/imm32
    ff          6/subop/push        1/mod/*+disp8   1/rm32/ECX    .           .             .           .           0xc/disp8       .                 # push *(ECX+12)
    # . . call
    e8/call  check-string-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
$test-get-or-insert-slice:third-call:
    # - insert a new key, verify that it was inserted
    # (EAX..EDX) = "data"
    b8/copy-to-EAX  "data"/imm32
    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           2/r32/EDX   .               .                 # copy *EAX to EDX
    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  2/index/EDX   .           2/r32/EDX   4/disp8         .                 # copy EAX+EDX+4 to EDX
    05/add-to-EAX  4/imm32
    # var slice/EDX = {EAX, EDX}
    52/push-EDX
    50/push-EAX
    89/copy                         3/mod/direct    2/rm32/EDX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EDX
    # EAX = get-or-insert-slice(table, "data" slice, 8 bytes per row)
    # . . push args
    68/push  8/imm32/row-size
    52/push-EDX
    51/push-ECX
    # . . call
    e8/call  get-or-insert-slice/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # table gets a new row
    # check-ints-equal(EAX - table->data, 12, msg)  # second row's value slot returned
    # . check-ints-equal(EAX - table, 24, msg)
    # . . push args
    68/push  "F - test-get-or-insert-slice/6"/imm32
    68/push  0x18/imm32
    29/subtract                     3/mod/direct    0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # subtract ECX from EAX
    50/push-EAX
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # check-ints-equal(table->write, 2 rows = 16, msg)
    # . . push args
    68/push  "F - test-get-or-insert-slice/7"/imm32
    68/push  0x10/imm32/two-rows
    ff          6/subop/push        0/mod/indirect  1/rm32/ECX    .           .             .           .           .               .                 # push *ECX
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # check-string-equal(*table->data+8, "data", msg)
    # check-string-equal(*(table+20), "data", msg)
    # . . push args
    68/push  "F - test-get-or-insert-slice/8"/imm32
    68/push  "data"/imm32
    ff          6/subop/push        1/mod/*+disp8   1/rm32/ECX    .           .             .           .           0x14/disp8      .                 # push *(ECX+20)
    # . . call
    e8/call  check-string-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
$test-get-or-insert-slice:end:
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

# (re)compute the bounds of the next word in the line
# return empty string on reaching end of file
next-word:  # line : (address stream byte), out : (address slice)
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # . save registers
    50/push-EAX
    51/push-ECX
    56/push-ESI
    57/push-EDI
    # ESI = line
    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   8/disp8         .                 # copy *(EBP+8) to ESI
    # EDI = out
    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           7/r32/EDI   0xc/disp8       .                 # copy *(EBP+12) to EDI
    # skip-chars-matching(line, ' ')
    # . . push args
    68/push  0x20/imm32/space
    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
    # . . call
    e8/call  skip-chars-matching/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
$next-word:check0:
    # if (line->read >= line->write) clear out and return
    # . EAX = line->read
    8b/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           0/r32/EAX   4/disp8         .                 # copy *(ESI+4) to EAX
    # . if (EAX < line->write) goto next check
    3b/compare                      0/mod/indirect  6/rm32/ESI    .           .             .           0/r32/EAX   .               .                 # compare EAX with *ESI
    7c/jump-if-lesser  $next-word:check-for-comment/disp8
    # . return out = {0, 0}
    c7          0/subop/copy        0/mod/direct    7/rm32/EDI    .           .             .           .           .               0/imm32           # copy to *EDI
    c7          0/subop/copy        1/mod/*+disp8   7/rm32/EDI    .           .             .           .           4/disp8         0/imm32           # copy to *(EDI+4)
    eb/jump  $next-word:end/disp8
$next-word:check-for-comment:
    # out->start = &line->data[line->read]
    8b/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           1/r32/ECX   4/disp8         .                 # copy *(ESI+4) to ECX
    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    6/base/ESI  1/index/ECX   .           0/r32/EAX   0xc/disp8       .                 # copy ESI+ECX+12 to EAX
    89/copy                         0/mod/indirect  7/rm32/EDI    .           .             .           0/r32/EAX   .               .                 # copy EAX to *EDI
    # if (line->data[line->read] == '#') out->end = &line->data[line->write]), skip rest of stream and return
    # . EAX = line->data[line->read]
    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
    8a/copy-byte                    1/mod/*+disp8   4/rm32/sib    6/base/ESI  1/index/ECX   .           0/r32/AL    0xc/disp8       .                 # copy byte at *(ESI+ECX+12) to AL
    # . compare
    3d/compare-EAX-and  0x23/imm32/pound
    75/jump-if-not-equal  $next-word:regular-word/disp8
$next-word:comment:
    # . out->end = &line->data[line->write]
    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           0/r32/EAX   .               .                 # copy *ESI to EAX
    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    6/base/ESI  0/index/EAX   .           0/r32/EAX   0xc/disp8       .                 # copy ESI+EAX+12 to EAX
    89/copy                         1/mod/*+disp8   7/rm32/EDI    .           .             .           0/r32/EAX   4/disp8         .                 # copy EAX to *(EDI+4)
    # . line->read = line->write
    89/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           0/r32/EAX   4/disp8         .                 # copy EAX to *(ESI+4)
    # . return
    eb/jump  $next-word:end/disp8
$next-word:regular-word:
    # otherwise skip-chars-not-matching-whitespace(line)  # including trailing newline
    # . . push args
    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
    # . . call
    e8/call  skip-chars-not-matching-whitespace/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # out->end = &line->data[line->read]
    8b/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           1/r32/ECX   4/disp8         .                 # copy *(ESI+4) to ECX
    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    6/base/ESI  1/index/ECX   .           0/r32/EAX   0xc/disp8       .                 # copy ESI+ECX+12 to EAX
    89/copy                         1/mod/*+disp8   7/rm32/EDI    .           .             .           0/r32/EAX   4/disp8         .                 # copy EAX to *(EDI+4)
$next-word:end:
    # . restore registers
    5f/pop-to-EDI
    5e/pop-to-ESI
    59/pop-to-ECX
    58/pop-to-EAX
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

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

test-next-word-returns-empty-string-on-eof:
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # setup
    # . clear-stream(_test-stream)
    # . . push args
    68/push  _test-stream/imm32
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # var slice/ECX = {0, 0}
    68/push  0/imm32/limit
    68/push  0/imm32/curr
    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
    # write nothing to _test-stream
    # next-word(_test-stream, slice)
    # . . push args
    51/push-ECX
    68/push  _test-stream/imm32
    # . . call
    e8/call  next-word/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # check-ints-equal(slice->end - slice->start, 0, msg)
    # . . push args
    68/push  "F - test-next-word-returns-empty-string-on-eof"/imm32
    68/push  0/imm32
    # . . push slice->end - slice->start
    8b/copy                         1/mod/*+disp8   1/rm32/ECX    .           .             .           0/r32/EAX   4/disp8         .                 # copy *(ECX+4) to EAX
    2b/subtract                     0/mod/indirect  1/rm32/ECX    .           .             .           0/r32/EAX   .               .                 # subtract *ECX from EAX
    50/push-EAX
    # . . call
    e8/call  check-ints-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

# write an entire stream's contents to a buffered-file
# ways to do this:
#   - construct a 'maximal slice' and pass it to write-slice-buffered
#   - flush the buffered-file and pass the stream directly to its fd (disabling buffering)
# we'll go with the first way for now
write-stream-data:  # f : (address buffered-file), s : (address stream) -> <void>
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # . save registers
    50/push-EAX
    51/push-ECX
    56/push-ESI
    # ESI = s
    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   0xc/disp8       .                 # copy *(EBP+12) to ESI
    # var slice/ECX = {s->data, s->data + s->write}
    # . push s->data + s->write
    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           0/r32/EAX   .               .                 # copy *ESI to EAX
    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    6/base/ESI  0/index/EAX   .           0/r32/EAX   0xc/disp8       .                 # copy ESI+EAX+12 to EAX
    50/push-EAX
    # . push s->data
    8d/copy-address                 1/mod/*+disp8   6/rm32/ESI    .           .             .           0/r32/EAX   0xc/disp8       .                 # copy ESI+12 to EAX
    50/push-EAX
    # . ECX = ESP
    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
    # write-slice-buffered(f, slice)
    # . . push args
    51/push-ECX
    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
    # . . call
    e8/call  write-slice-buffered/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
$write-stream-data:end:
    # . restore locals
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # . restore registers
    5e/pop-to-ESI
    59/pop-to-ECX
    58/pop-to-EAX
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

test-write-stream-data:
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # setup
    # . clear-stream(_test-output-stream)
    # . . push args
    68/push  _test-output-stream/imm32
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # . clear-stream(_test-output-buffered-file+4)
    # . . push args
    b8/copy-to-EAX  _test-output-buffered-file/imm32
    05/add-to-EAX  4/imm32
    50/push-EAX
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # . clear-stream(_test-input-stream)
    # . . push args
    68/push  _test-input-stream/imm32
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # initialize input
    # . write(_test-input-stream, "abcd")
    # . . push args
    68/push  "abcd"/imm32
    68/push  _test-input-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # write-stream-data(_test-output-buffered-file, _test-input-stream)
    # . . push args
    68/push  _test-input-stream/imm32
    68/push  _test-output-buffered-file/imm32
    # . . call
    e8/call  write-stream-data/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # check that the write happened as expected
    # . flush(_test-output-buffered-file)
    # . . push args
    68/push  _test-output-buffered-file/imm32
    # . . call
    e8/call  flush/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # . check-stream-equal(_test-output-stream, "abcd", msg)
    # . . push args
    68/push  "F - test-write-stream-data"/imm32
    68/push  "abcd"/imm32
    68/push  _test-output-stream/imm32
    # . . call
    e8/call  check-stream-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

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

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

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

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

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

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

compute-width: # word : (address array byte) -> EAX : int
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # . save registers
    51/push-ECX
    # EAX = word
    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           0/r32/EAX   8/disp8         .                 # copy *(EBP+8) to ECX
    # ECX = word + word->length
    8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/EAX  1/index/ECX   .           1/r32/ECX   4/disp8         .                 # copy EAX+ECX+4 to ECX
    # EAX = word->data
    05/add-to-EAX  4/imm32
    # var in/ECX : (address slice) = {EAX, ECX}
    51/push-ECX
    50/push-EAX
    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
    # return compute-width-of-slice(ECX)
    # . . push args
    51/push-ECX
    # . . call
    e8/call  compute-width-of-slice/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
$compute-width:end:
    # . reclaim locals
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # . restore registers
    59/pop-to-ECX
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

compute-width-of-slice: # s : (address slice) -> EAX : int
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # . save registers
    51/push-ECX
    # ECX = s
    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           1/r32/ECX   8/disp8         .                 # copy *(EBP+8) to ECX
    # if (has-metadata?(word, "imm32")) return 4
    # . EAX = has-metadata?(word, "imm32")
    # . . push args
    68/push  "imm32"/imm32
    51/push-ECX
    # . . call
    e8/call  has-metadata?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # . if (EAX != 0) return 4
    3d/compare-EAX-and  0/imm32
    b8/copy-to-EAX  4/imm32         # ZF is set, so we can overwrite EAX now
    75/jump-if-not-equal  $compute-width-of-slice:end/disp8
    # if (has-metadata?(word, "disp32")) return 4
    # . EAX = has-metadata?(word, "disp32")
    # . . push args
    68/push  "disp32"/imm32
    51/push-ECX
    # . . call
    e8/call  has-metadata?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # . if (EAX != 0) return 4
    3d/compare-EAX-and  0/imm32
    b8/copy-to-EAX  4/imm32         # ZF is set, so we can overwrite EAX now
    75/jump-if-not-equal  $compute-width-of-slice:end/disp8
    # if (has-metadata?(word, "imm16")) return 2
    # . EAX = has-metadata?(word, "imm16")
    # . . push args
    68/push  "imm16"/imm32
    51/push-ECX
    # . . call
    e8/call  has-metadata?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # . if (EAX != 0) return 2
    3d/compare-EAX-and  0/imm32
    b8/copy-to-EAX  2/imm32         # ZF is set, so we can overwrite EAX now
    75/jump-if-not-equal  $compute-width-of-slice:end/disp8
    # if (has-metadata?(word, "disp16")) return 2
    # . EAX = has-metadata?(word, "disp16")
    # . . push args
    68/push  "disp16"/imm32
    51/push-ECX
    # . . call
    e8/call  has-metadata?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # . if (EAX != 0) return 2
    3d/compare-EAX-and  0/imm32
    b8/copy-to-EAX  2/imm32         # ZF is set, so we can overwrite EAX now
    75/jump-if-not-equal  $compute-width-of-slice:end/disp8
    # otherwise return 1
    b8/copy-to-EAX  1/imm32
$compute-width-of-slice:end:
    # . restore registers
    59/pop-to-ECX
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

test-compute-width:
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
$test-compute-width:imm8:
    # EAX = compute-width("0x2/imm8")
    68/push "0x2/imm8"/imm32
    e8/call  compute-width/disp32
    # . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # check-ints-equal(EAX, 1, msg)
    68/push "F - test-compute-width: 0x2/imm8"/imm32
    50/push-EAX
    68/push 1/imm32
    e8/call  check-ints-equal/disp32
    # . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
$test-compute-width:imm16:
    # EAX = compute-width("4/imm16")
    68/push "4/imm16"/imm32
    e8/call  compute-width/disp32
    # . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # check-ints-equal(EAX, 2, msg)
    68/push "F - test-compute-width: 4/imm16"/imm32
    50/push-EAX
    68/push 2/imm32
    e8/call  check-ints-equal/disp32
    # . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
$test-compute-width:imm32:
    # EAX = compute-width("4/imm32")
    68/push "4/imm32"/imm32
    e8/call  compute-width/disp32
    # . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # check-ints-equal(EAX, 4, msg)
    68/push "F - test-compute-width: 4/imm32"/imm32
    50/push-EAX
    68/push 4/imm32
    e8/call  check-ints-equal/disp32
    # . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
$test-compute-width:disp8:
    # EAX = compute-width("foo/disp8")
    68/push "foo/disp8"/imm32
    e8/call  compute-width/disp32
    # . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # check-ints-equal(EAX, 1, msg)
    68/push "F - test-compute-width: foo/disp8"/imm32
    50/push-EAX
    68/push 1/imm32
    e8/call  check-ints-equal/disp32
    # . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
$test-compute-width:disp16:
    # EAX = compute-width("foo/disp16")
    68/push "foo/disp16"/imm32
    e8/call  compute-width/disp32
    # . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # check-ints-equal(EAX, 2, msg)
    68/push "F - test-compute-width: foo/disp16"/imm32
    50/push-EAX
    68/push 2/imm32
    e8/call  check-ints-equal/disp32
    # . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
$test-compute-width:disp32:
    # EAX = compute-width("foo/disp32")
    68/push "foo/disp32"/imm32
    e8/call  compute-width/disp32
    # . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # check-ints-equal(EAX, 4, msg)
    68/push "F - test-compute-width: foo/disp32"/imm32
    50/push-EAX
    68/push 4/imm32
    e8/call  check-ints-equal/disp32
    # . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
$test-compute-width:no-metadata:
    # EAX = compute-width("45")
    68/push "45"/imm32
    e8/call  compute-width/disp32
    # . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # check-ints-equal(EAX, 1, msg)
    68/push "F - test-compute-width: 45 (no metadata)"/imm32
    50/push-EAX
    68/push 1/imm32
    e8/call  check-ints-equal/disp32
    # . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

is-label?: # word : (address slice) -> EAX : boolean
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # . save registers
    51/push-ECX
    # ECX = word
    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           1/r32/ECX   8/disp8         .                 # copy *(EBP+8) to ECX
    # ECX = word->end
    8b/copy                         1/mod/*+disp8   1/rm32/ECX    .           .             .           1/r32/ECX   4/disp8         .                 # copy *(ECX+4) to ECX
    # return *(word->end - 1) == ':'
    # . EAX = 0
    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
    # . EAX = *((char *) word->end - 1)
    8a/copy-byte                    1/mod/*+disp8   1/rm32/ECX    .           .             .           0/r32/AL    -1/disp8         .                 # copy byte at *(ECX-1) to AL
    # . return (EAX == ':')
    3d/compare-EAX-and  0x3a/imm32/colon
    b8/copy-to-EAX  1/imm32/true
    74/jump-if-equal  $is-label?:end/disp8
    b8/copy-to-EAX  0/imm32/false
$is-label?:end:
    # . restore registers
    59/pop-to-ECX
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

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

== data

_test-input-stream:
    # current write index
    0/imm32
    # current read index
    0/imm32
    # length
    0x100/imm32  # 256 bytes
    # data (16 lines x 16 bytes/line)
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

# a test buffered file for _test-input-stream
_test-input-buffered-file:
    # file descriptor or (address stream)
    _test-input-stream/imm32
    # current write index
    0/imm32
    # current read index
    0/imm32
    # length
    6/imm32
    # data
    00 00 00 00 00 00  # 6 bytes

_test-output-stream:
    # current write index
    0/imm32
    # current read index
    0/imm32
    # length
    0x100/imm32  # 256 bytes
    # data (16 lines x 16 bytes/line)
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

# a test buffered file for _test-output-stream
_test-output-buffered-file:
    # file descriptor or (address stream)
    _test-output-stream/imm32
    # current write index
    0/imm32
    # current read index
    0/imm32
    # length
    6/imm32
    # data
    00 00 00 00 00 00  # 6 bytes

_test-data-segment:
  64/d 61/a 74/t 61/a
_test-data-segment-end:

# . . vim:nowrap:textwidth=0