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# some primitives for checking stream contents

== 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

# main:
#?     e8/call test-next-stream-line-equal-stops-at-newline/disp32
    e8/call  run-tests/disp32  # 'run-tests' is a function created automatically by SubX. It calls all functions that start with 'test-'.
    # syscall(exit, Num-test-failures)
    8b/copy                         0/mod/indirect  5/rm32/.disp32            .             .           3/r32/EBX   Num-test-failures/disp32          # copy *Num-test-failures to EBX
    b8/copy-to-EAX  1/imm32/exit
    cd/syscall  0x80/imm8

# compare all the data in a stream (ignoring the read pointer)
stream-data-equal?:  # f : (address stream), s : (address string) -> 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
    52/push-EDX
    56/push-ESI
    57/push-EDI
    # ESI = f
    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   8/disp8         .                 # copy *(EBP+8) to ESI
    # max/EDX = f->data + f->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   .           2/r32/EDX   0xc/disp8       .                 # copy ESI+EAX+12 to EDX
    # currf/ESI = f->data
    81          0/subop/add         3/mod/direct    6/rm32/ESI    .           .             .           .           .               0xc/imm32         # add to ESI
    # EDI = s
    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           7/r32/EDI   0xc/disp8       .                 # copy *(EBP+12) to EDI
    # if (f->write != s->length) return false
    39/compare                      0/mod/indirect  7/rm32/EDI    .           .             .           0/r32/EAX   .               .                 # compare *EDI and EAX
    75/jump-if-not-equal  $stream-data-equal?:false/disp8
    # currs/EDI = s->data
    81          0/subop/add         3/mod/direct    7/rm32/EDI    .           .             .           .           .               4/imm32           # add to EDI
    # EAX = ECX = 0
    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
    31/xor                          3/mod/direct    1/rm32/ECX    .           .             .           1/r32/ECX   .               .                 # clear ECX
$stream-data-equal?:loop:
    # if (curr >= max) return true
    39/compare                      3/mod/direct    6/rm32/ESI    .           .             .           2/r32/EDX   .               .                 # compare ESI with EDX
    7d/jump-if-greater-or-equal  $stream-data-equal?:true/disp8
    # AL = *currs
    8a/copy-byte                    0/mod/indirect  6/rm32/ESI    .           .             .           0/r32/AL    .               .                 # copy byte at *ESI to AL
    # CL = *curr
    8a/copy-byte                    0/mod/indirect  7/rm32/EDI    .           .             .           1/r32/CL    .               .                 # copy byte at *EDI to CL
    # if (EAX != ECX) return false
    39/compare                      3/mod/direct    0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # compare EAX and ECX
    75/jump-if-not-equal  $stream-data-equal?:false/disp8
    # ++f
    46/increment-ESI
    # ++curr
    47/increment-EDI
    eb/jump $stream-data-equal?:loop/disp8
$stream-data-equal?:false:
    b8/copy-to-EAX  0/imm32
    eb/jump  $stream-data-equal?:end/disp8
$stream-data-equal?:true:
    b8/copy-to-EAX  1/imm32
$stream-data-equal?:end:
    # . 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-stream-data-equal:
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # 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
    # write(_test-stream, "Abc")
    # . . push args
    68/push  "Abc"/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # EAX = stream-data-equal?(_test-stream, "Abc")
    # . . push args
    68/push  "Abc"/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  stream-data-equal?/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-stream-data-equal"/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
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

test-stream-data-equal-2:
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # 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
    # write(_test-stream, "Abc")
    # . . push args
    68/push  "Abc"/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # EAX = stream-data-equal?(_test-stream, "Abd")
    # . . push args
    68/push  "Abd"/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  stream-data-equal?/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-stream-data-equal-2"/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

test-stream-data-equal-length-check:
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # 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
    # write(_test-stream, "Abc")
    # . . push args
    68/push  "Abc"/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # EAX = stream-data-equal?(_test-stream, "Abcd")
    # . . push args
    68/push  "Abcd"/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  stream-data-equal?/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-stream-data-equal-length-check"/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

# helper for later tests
check-stream-equal:  # f : (address stream), s : (address string), msg : (address string)
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # . save registers
    50/push-EAX
    # EAX = stream-data-equal?(f, s)
    # . . push args
    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
    # . . call
    e8/call  stream-data-equal?/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
    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x10/disp8      .                 # push *(EBP+16)
    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
    # . restore registers
    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

# scan the next line until newline starting from f->read and compare it with
# 's' (ignoring the trailing newline)
# on success, set f->read to after the next newline
# on failure, leave f->read unmodified
# this function is usually used only in tests, so we repeatedly write f->read
next-stream-line-equal?:  # f : (address stream), s : (address string) -> EAX : boolean
    # pseudocode:
    #   currf = f->read  # bound: f->write
    #   currs = 0  # bound : s->length
    #   while true:
    #     if (currf >= f->write)
    #       return currs >= s->length
    #     if (f[currf] == '\n')
    #       ++currf
    #       return currs >= s->length
    #     if (currs >= s->length) return false  # the current line of f still has data to match
    #     if (f[currf] != s[currs]) return false
    #     ++currf
    #     ++currs
    #
    # collapsing the two branches that can return true:
    #   currf = f->read  # bound: f->write
    #   currs = 0  # bound : s->length
    #   while true:
    #     if (currf >= f->write) break
    #     if (f[currf] == '\n') break
    #     if (currs >= s->length) return false  # the current line of f still has data to match
    #     if (f[currf] != s[currs]) return false
    #     ++currf
    #     ++currs
    #   ++currf  # skip '\n'
    #   return currs >= s->length
    # Here the final `++currf` is sometimes unnecessary (if we're already at the end of the stream)
    #
    # registers:
    #   f: ESI
    #   s: EDI
    #   currf: ECX
    #   currs: EDX
    #   f[currf]: EAX
    #   s[currs]: EBX
    #
    # . 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 = f
    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   8/disp8         .                 # copy *(EBP+8) to ESI
    # currf/ECX = f->read
    8b/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           1/r32/ECX   4/disp8         .                 # copy *(ESI+4) to ECX
    # EDI = s
    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           7/r32/EDI   0xc/disp8       .                 # copy *(EBP+12) to EDI
    # currs/EDX = 0
    31/xor                          3/mod/direct    2/rm32/EDX    .           .             .           2/r32/EDX   .               .                 # clear EDX
    # EAX = EBX = 0
    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
    31/xor                          3/mod/direct    3/rm32/EBX    .           .             .           3/r32/EBX   .               .                 # clear EBX
$next-stream-line-equal?:loop:
    # if (currf >= f->write) break
    3b/compare                      0/mod/indirect  6/rm32/ESI    .           .             .           1/r32/ECX   .               .                 # compare ECX with *ESI
    7d/jump-if-greater-or-equal  $next-stream-line-equal?:break/disp8
    # AL = *(f->data + f->read)
    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
    # if (EAX == '\n') break
    81          7/subop/compare     3/mod/direct    0/rm32/EAX    .           .             .           .           .               0xa/imm32/newline # compare EAX
    74/jump-if-equal  $next-stream-line-equal?:break/disp8
    # if (currs >= s->length) return false
    3b/compare                      0/mod/indirect  7/rm32/EDI    .           .             .           2/r32/EDX   .               .                 # compare EDX with *EDI
    7d/jump-if-greater-or-equal  $next-stream-line-equal?:false/disp8
    # BL = *(s->data + currs)
    8a/copy-byte                    1/mod/*+disp8   4/rm32/sib    7/base/EDI  2/index/EDX   .           3/r32/BL    4/disp8         .                 # copy byte at *(EDI+EDX+4) to BL
    # if (EAX != EBX) return false
    39/compare                      3/mod/direct    0/rm32/EAX    .           .             .           3/r32/EBX   .               .                 # compare EAX and EBX
    75/jump-if-not-equal  $next-stream-line-equal?:false/disp8
    # ++currf
    41/increment-ECX
    # ++currs
    42/increment-EDX
    eb/jump $next-stream-line-equal?:loop/disp8
$next-stream-line-equal?:break:
    # ++currf
    41/increment-ECX
    # if (currs >= s->length) return true
    3b/compare                      0/mod/indirect  7/rm32/EDI    .           .             .           2/r32/EDX   .               .                 # compare EDX with *EDI
    7c/jump-if-lesser  $next-stream-line-equal?:false/disp8
$next-stream-line-equal?:true:
    b8/copy-to-EAX  1/imm32
    # persist f->read on success
    89/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           1/r32/ECX   4/disp8         .                 # copy ECX to *(ESI+4)
    eb/jump  $next-stream-line-equal?:end/disp8
$next-stream-line-equal?:false:
    b8/copy-to-EAX  0/imm32
$next-stream-line-equal?:end:
    # . 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-next-stream-line-equal-stops-at-newline:
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # 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
    # write(_test-stream, "Abc\ndef")
    # . write(_test-stream, "Abc")
    # . . push args
    68/push  "Abc"/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # . write(_test-stream, Newline)
    # . . push args
    68/push  Newline/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # . write(_test-stream, "def")
    # . . push args
    68/push  "def"/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
    # EAX = next-stream-line-equal?(_test-stream, "Abc")
    # . . push args
    68/push  "Abc"/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  next-stream-line-equal?/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-next-stream-line-equal-stops-at-newline"/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
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

test-next-stream-line-equal-stops-at-newline-2:
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # 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
    # write(_test-stream, "Abc\ndef")
    # . write(_test-stream, "Abc")
    # . . push args
    68/push  "Abc"/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # . write(_test-stream, Newline)
    # . . push args
    68/push  Newline/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # . write(_test-stream, "def")
    # . . push args
    68/push  "def"/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
    # EAX = next-stream-line-equal?(_test-stream, "def")
    # . . push args
    68/push  "def"/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  next-stream-line-equal?/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-next-stream-line-equal-stops-at-newline-2"/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

test-next-stream-line-equal-skips-newline:
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # 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
    # write(_test-stream, "Abc\ndef\n")
    # . write(_test-stream, "Abc")
    # . . push args
    68/push  "Abc"/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # . write(_test-stream, Newline)
    # . . push args
    68/push  Newline/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # . write(_test-stream, "def")
    # . . push args
    68/push  "def"/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # . write(_test-stream, Newline)
    # . . push args
    68/push  Newline/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-stream-line-equal?(_test-stream, "Abc")
    # . . push args
    68/push  "Abc"/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  next-stream-line-equal?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # EAX = next-stream-line-equal?(_test-stream, "def")
    # . . push args
    68/push  "def"/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  next-stream-line-equal?/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-next-stream-line-equal-skips-newline"/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
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

test-next-stream-line-equal-handles-final-line:
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # 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
    # write(_test-stream, "Abc\ndef")
    # . write(_test-stream, "Abc")
    # . . push args
    68/push  "Abc"/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # . write(_test-stream, Newline)
    # . . push args
    68/push  Newline/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # . write(_test-stream, "def")
    # . . push args
    68/push  "def"/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-stream-line-equal?(_test-stream, "Abc")
    # . . push args
    68/push  "Abc"/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  next-stream-line-equal?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # EAX = next-stream-line-equal?(_test-stream, "def")
    # . . push args
    68/push  "def"/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  next-stream-line-equal?/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-next-stream-line-equal-skips-newline"/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
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

test-next-stream-line-equal-always-fails-after-eof:
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # 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
    # write nothing
    # EAX = next-stream-line-equal?(_test-stream, "")
    # . . push args
    68/push  ""/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  next-stream-line-equal?/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-next-stream-line-equal-always-fails-after-eof"/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
    # EAX = next-stream-line-equal?(_test-stream, "")
    # . . push args
    68/push  ""/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  next-stream-line-equal?/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-next-stream-line-equal-always-fails-after-eof/2"/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
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

# helper for later tests
check-next-stream-line-equal:
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # . save registers
    50/push-EAX
    # EAX = next-stream-line-equal?(f, s)
    # . . push args
    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
    # . . call
    e8/call  next-stream-line-equal?/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
    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0x10/disp8      .                 # push *(EBP+16)
    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
    # . restore registers
    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