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# new data structure: a slice is an open interval of addresses [start, end)
# that includes 'start' but not 'end'

== 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

slice-empty?:  # s : (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 = s
    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           1/r32/ECX   8/disp8         .                 # copy *(EBP+8) to ECX
    # if (s->start == s->end) return true
    # . EAX = s->start
    8b/copy                         0/mod/indirect  1/rm32/ECX    .           .             .           0/r32/EAX   .               .                 # copy *ECX to EAX
    # . compare EAX and s->end
    39/compare                      1/mod/*+disp8   1/rm32/ECX    .           .             .           0/r32/EAX   4/disp8         .                 # compare EAX and *(ECX+4)
    b8/copy-to-EAX  1/imm32/true
    74/jump-if-equal  $slice-empty?:end/disp8
    b8/copy-to-EAX  0/imm32/false
$slice-empty?: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-slice-empty-true:
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # var slice/ECX = {34, 34}
    68/push  34/imm32/end
    68/push  34/imm32/start
    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
    # slice-empty?(slice)
    # . . push args
    51/push-ECX
    # . . call
    e8/call  slice-empty?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # check-ints-equal(EAX, 1, msg)
    # . . push args
    68/push  "F - test-slice-empty-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
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

test-slice-empty-false:
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # var slice/ECX = {34, 23}
    68/push  23/imm32/end
    68/push  34/imm32/start
    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
    # slice-empty?(slice)
    # . . push args
    51/push-ECX
    # . . call
    e8/call  slice-empty?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # check-ints-equal(EAX, 0, msg)
    # . . push args
    68/push  "F - test-slice-empty-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

slice-equal?:  # s : (address slice), p : (address string) -> EAX : boolean
    # pseudocode:
    #   if (p == 0) return (s == 0)
    #   currs = s->start
    #   maxs = s->end
    #   if (maxs - currs != p->length) return false
    #   currp = p->data
    #   while currs < maxs
    #     if (*currs != *currp) return false
    #     ++currs
    #     ++currp
    #   return true
    #
    # registers:
    #   currs: EDX
    #   maxs: ESI
    #   currp: EBX
    #   *currs: EAX
    #   *currp: ECX
    #
    # . 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
    53/push-EBX
    56/push-ESI
    # ESI = s
    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   8/disp8         .                 # copy *(EBP+8) to ESI
    # currs/EDX = s->start
    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           2/r32/EDX   .               .                 # copy *ESI to EDX
    # maxs/ESI = s->end
    8b/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           6/r32/ESI   4/disp8         .                 # copy *(ESI+4) to ESI
    # EAX = maxs - currs
    89/copy                         3/mod/direct    0/rm32/EAX    .           .             .           6/r32/ESI   .               .                 # copy ESI to EAX
    29/subtract                     3/mod/direct    0/rm32/EAX    .           .             .           2/r32/EDX   .               .                 # subtract EDX from EAX
    # EBX = p
    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           3/r32/EBX   0xc/disp8       .                 # copy *(EBP+12) to EBX
    # if (p != 0) goto next check
    81          7/subop/compare     3/mod/direct    3/rm32/EBX    .           .             .           .           .               0/imm32           # compare EBX
    75/jump-if-not-equal  $slice-equal?:nonnull-string/disp8
$slice-equal?:null-string:
    # return s->start == s->end
    3d/compare-EAX-and  0/imm32
    74/jump-if-equal  $slice-equal?:true/disp8
    eb/jump  $slice-equal?:false/disp8
$slice-equal?:nonnull-string:
    # if (EAX != p->length) return false
    39/compare                      0/mod/indirect  3/rm32/EBX    .           .             .           0/r32/EAX   .               .                 # compare *EBX and EAX
    75/jump-if-not-equal  $slice-equal?:false/disp8
    # currp/EBX = p->data
    81          0/subop/add         3/mod/direct    3/rm32/EBX    .           .             .           .           .               4/imm32           # add to EBX
    # 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
$slice-equal?:loop:
    # if (currs >= maxs) return true
    39/compare                      3/mod/direct    2/rm32/EDX    .           .             .           6/r32/ESI   .               .                 # compare EDX with ESI
    73/jump-if-greater-or-equal-unsigned  $slice-equal?:true/disp8
    # AL = *currp
    8a/copy-byte                    0/mod/indirect  3/rm32/EBX    .           .             .           0/r32/AL    .               .                 # copy byte at *EBX to AL
    # CL = *currs
    8a/copy-byte                    0/mod/indirect  2/rm32/EDX    .           .             .           1/r32/CL    .               .                 # copy byte at *EDX 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  $slice-equal?:false/disp8
    # ++currp
    43/increment-EBX
    # ++currs
    42/increment-EDX
    eb/jump $slice-equal?:loop/disp8
$slice-equal?:false:
    b8/copy-to-EAX  0/imm32
    eb/jump  $slice-equal?:end/disp8
$slice-equal?:true:
    b8/copy-to-EAX  1/imm32
$slice-equal?:end:
    # . restore registers
    5e/pop-to-ESI
    5b/pop-to-EBX
    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-slice-equal:
    # - slice-equal?(slice("Abc"), "Abc") == 1
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # (EAX..ECX) = "Abc"
    b8/copy-to-EAX  "Abc"/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
    # EAX = slice-equal?(ECX, "Abc")
    # . . push args
    68/push  "Abc"/imm32
    51/push-ECX
    # . . call
    e8/call  slice-equal?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # check-ints-equal(EAX, 1, msg)
    # . . push args
    68/push  "F - test-slice-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-slice-equal-false:
    # - slice-equal?(slice("bcd"), "Abc") == 0
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # (EAX..ECX) = "bcd"
    b8/copy-to-EAX  "bcd"/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
    # EAX = slice-equal?(ECX, "Abc")
    # . . push args
    68/push  "Abc"/imm32
    51/push-ECX
    # . . call
    e8/call  slice-equal?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # check-ints-equal(EAX, 0, msg)
    # . . push args
    68/push  "F - test-slice-equal-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

test-slice-equal-too-long:
    # - slice-equal?(slice("Abcd"), "Abc") == 0
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # (EAX..ECX) = "Abcd"
    b8/copy-to-EAX  "Abcd"/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
    # EAX = slice-equal?(ECX, "Abc")
    # . . push args
    68/push  "Abc"/imm32
    51/push-ECX
    # . . call
    e8/call  slice-equal?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # check-ints-equal(EAX, 0, msg)
    # . . push args
    68/push  "F - test-slice-equal-too-long"/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-slice-equal-too-short:
    # - slice-equal?(slice("A"), "Abc") == 0
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # (EAX..ECX) = "A"
    b8/copy-to-EAX  "A"/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
    # EAX = slice-equal?(ECX, "Abc")
    # . . push args
    68/push  "Abc"/imm32
    51/push-ECX
    # . . call
    e8/call  slice-equal?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # check-ints-equal(EAX, 0, msg)
    # . . push args
    68/push  "F - test-slice-equal-too-short"/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-slice-equal-empty:
    # - slice-equal?(slice(""), "Abc") == 0
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # var slice/ECX
    68/push  0/imm32/end
    68/push  0/imm32/start
    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
    # EAX = slice-equal?(ECX, "Abc")
    # . . push args
    68/push  "Abc"/imm32
    51/push-ECX
    # . . call
    e8/call  slice-equal?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # check-ints-equal(EAX, 0, msg)
    # . . push args
    68/push  "F - test-slice-equal-empty"/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-slice-equal-with-empty:
    # - slice-equal?(slice("Ab"), "") == 0
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # (EAX..ECX) = "Ab"
    b8/copy-to-EAX  "Ab"/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
    # EAX = slice-equal?(ECX, "")
    # . . push args
    68/push  ""/imm32
    51/push-ECX
    # . . call
    e8/call  slice-equal?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # check-ints-equal(EAX, 0, msg)
    # . . push args
    68/push  "F - test-slice-equal-with-empty"/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-slice-equal-empty-with-empty:
    # - slice-equal?(slice(""), "") == 1
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # var slice/ECX
    68/push  0/imm32/end
    68/push  0/imm32/start
    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           4/r32/ESP   .               .                 # copy ESP to ECX
    # EAX = slice-equal?(ECX, "")
    # . . push args
    68/push  ""/imm32
    51/push-ECX
    # . . call
    e8/call  slice-equal?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # check-ints-equal(EAX, 1, msg)
    # . . push args
    68/push  "F - test-slice-equal-empty-with-empty"/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-slice-equal-with-null:
    # - slice-equal?(slice("Ab"), null) == 0
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # (EAX..ECX) = "Ab"
    b8/copy-to-EAX  "Ab"/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
    # EAX = slice-equal?(ECX, 0)
    # . . push args
    68/push  0/imm32
    51/push-ECX
    # . . call
    e8/call  slice-equal?/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # check-ints-equal(EAX, 0, msg)
    # . . push args
    68/push  "F - test-slice-equal-with-null"/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

slice-starts-with?:  # s : (address slice), head : (address string) -> EAX : boolean
    # pseudocode
    #   lenh = head->length
    #   if (lenh > s->end - s->start) return false
    #   i = 0
    #   currs = s->start
    #   currp = head->data
    #   while i < lenh
    #     if (*currs != *currh) return false
    #     ++i
    #     ++currs
    #     ++currh
    #   return true
    #
    # registers:
    #   currs: ESI
    #   currh: EDI
    #   *currs: EAX
    #   *currh: EBX
    #   i: ECX
    #   lenh: EDX
    #
    # . 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
    53/push-EBX
    56/push-ESI
    57/push-EDI
    # ESI = s
    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   8/disp8         .                 # copy *(EBP+8) to ESI
    # ECX = s->end - s->start
    8b/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           1/r32/ECX   4/disp8         .                 # copy *(ESI+4) to ECX
    2b/subtract                     0/mod/indirect  6/rm32/ESI    .           .             .           1/r32/ECX   .               .                 # subtract *ESI from ECX
    # EDI = head
    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           7/r32/EDI   0xc/disp8       .                 # copy *(EBP+12) to EDI
    # lenh/EDX = head->length
    8b/copy                         0/mod/indirect  7/rm32/EDI    .           .             .           2/r32/EDX   .               .                 # copy *EDI to EDX
    # if (lenh > s->end - s->start) return false
    39/compare                      3/mod/direct    2/rm32/EDX    .           .             .           1/r32/ECX   .               .                 # compare EDX with ECX
    7f/jump-if-greater  $slice-starts-with?:false/disp8
    # currs/ESI = s->start
    8b/subtract                     0/mod/indirect  6/rm32/ESI    .           .             .           6/r32/ESI   .               .                 # copy *ESI to ESI
    # currh/EDI = head->data
    81          0/subop/add         3/mod/direct    7/rm32/EDI    .           .             .           .           .               4/imm32           # add to EDI
    # i/ECX = 0
    31/xor                          3/mod/direct    1/rm32/ECX    .           .             .           1/r32/ECX   .               .                 # clear ECX
    # 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
$slice-starts-with?:loop:
    # if (i >= lenh) return true
    39/compare                      3/mod/direct    1/rm32/ECX    .           .             .           2/r32/EDX   .               .                 # compare ECX with EDX
    7d/jump-if-greater-or-equal  $slice-starts-with?:true/disp8
    # AL = *currs
    8a/copy-byte                    0/mod/indirect  6/rm32/ESI    .           .             .           0/r32/AL    .               .                 # copy byte at *ESI to AL
    # BL = *currh
    8a/copy-byte                    0/mod/indirect  7/rm32/EDI    .           .             .           3/r32/BL    .               .                 # copy byte at *EDI to BL
    # if (*currs != *currh) return false
    39/compare                      3/mod/direct    0/rm32/EAX    .           .             .           3/r32/EBX   .               .                 # compare EAX and EBX
    75/jump-if-not-equal  $slice-starts-with?:false/disp8
    # ++i
    41/increment-ECX
    # ++currs
    46/increment-ESI
    # ++currh
    47/increment-EDI
    eb/jump $slice-starts-with?:loop/disp8
$slice-starts-with?:true:
    b8/copy-to-EAX  1/imm32
    eb/jump  $slice-starts-with?:end/disp8
$slice-starts-with?:false:
    b8/copy-to-EAX  0/imm32
$slice-starts-with?:end:
    # . restore registers
    5f/pop-to-EDI
    5e/pop-to-ESI
    5b/pop-to-EBX
    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-slice-starts-with-single-character:
    # - slice-starts-with?(slice("Abc"), "A") == 1
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # (EAX..ECX) = "Abc"
    b8/copy-to-EAX  "Abc"/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
    # EAX = slice-starts-with?(ECX, "A")
    # . . push args
    68/push  "A"/imm32
    51/push-ECX
    # . . call
    e8/call  slice-starts-with?/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-slice-starts-with-single-character"/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-slice-starts-with-empty-string:
    # - slice-starts-with?(slice("Abc"), "") == 1
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # (EAX..ECX) = "Abc"
    b8/copy-to-EAX  "Abc"/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
    # EAX = slice-starts-with?(ECX, "")
    # . . push args
    68/push  ""/imm32
    51/push-ECX
    # . . call
    e8/call  slice-starts-with?/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-slice-starts-with-empty-string"/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-slice-starts-with-multiple-characters:
    # - slice-starts-with?(slice("Abc"), "Ab") == 1
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # (EAX..ECX) = "Abc"
    b8/copy-to-EAX  "Abc"/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
    # EAX = slice-starts-with?(ECX, "Ab")
    # . . push args
    68/push  "Ab"/imm32
    51/push-ECX
    # . . call
    e8/call  slice-starts-with?/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-slice-starts-with-multiple-characters"/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-slice-starts-with-entire-string:
    # - slice-starts-with?(slice("Abc"), "Abc") == 1
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # (EAX..ECX) = "Abc"
    b8/copy-to-EAX  "Abc"/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
    # EAX = slice-starts-with?(ECX, "Abc")
    # . . push args
    68/push  "Abc"/imm32
    51/push-ECX
    # . . call
    e8/call  slice-starts-with?/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-slice-starts-with-entire-string"/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-slice-starts-with-fails:
    # - slice-starts-with?(slice("Abc"), "Abd") == 1
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # (EAX..ECX) = "Abc"
    b8/copy-to-EAX  "Abc"/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
    # EAX = slice-starts-with?(ECX, "Abd")
    # . . push args
    68/push  "Abd"/imm32
    51/push-ECX
    # . . call
    e8/call  slice-starts-with?/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-slice-starts-with-fails"/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-slice-starts-with-fails-2:
    # - slice-starts-with?(slice("Abc"), "Ac") == 1
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # (EAX..ECX) = "Abc"
    b8/copy-to-EAX  "Abc"/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
    # EAX = slice-starts-with?(ECX, "Ac")
    # . . push args
    68/push  "Ac"/imm32
    51/push-ECX
    # . . call
    e8/call  slice-starts-with?/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-slice-starts-with-fails-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

# write a slice to a stream
# abort if the stream doesn't have enough space
write-slice:  # out : (address stream), s : (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
    52/push-EDX
    53/push-EBX
    56/push-ESI
    57/push-EDI
    # ESI = s
    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   0xc/disp8       .                 # copy *(EBP+12) to ESI
    # curr/ECX = s->start
    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           1/r32/ECX   .               .                 # copy *ESI to ECX
    # max/ESI = s->end
    8b/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           6/r32/ESI   4/disp8         .                 # copy *(ESI+4) to ESI
    # EDI = out
    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .                         7/r32/EDI   8/disp8         .                 # copy *(EBP+8) to EDI
    # EDX = out->length
    8b/copy                         1/mod/*+disp8   7/rm32/EDI    .           .             .           2/r32/EDX   8/disp8         .                 # copy *(EDI+8) to EDX
    # EBX = out->write
    8b/copy                         0/mod/indirect  7/rm32/EDI    .           .             .           3/r32/EBX   .               .                 # copy *EDI to EBX
$write-slice:loop:
    # if (curr >= max) break
    39/compare                      3/mod/direct    1/rm32/ECX    .           .             .           6/r32/ESI   .               .                 # compare ECX with ESI
    73/jump-if-greater-or-equal-unsigned  $write-slice:loop-end/disp8
    # if (out->write >= out->length) abort
    39/compare                      3/mod/direct    3/rm32/EBX    .           .             .           2/r32/EDX   .               .                 # compare EBX with EDX
    7d/jump-if-greater-or-equal  $write-slice:abort/disp8
    # out->data[out->write] = *in
    # . AL = *in
    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
    8a/copy-byte                    0/mod/indirect  1/rm32/ECX    .           .             .           0/r32/AL    .               .                 # copy byte at *ECX to AL
    # . out->data[out->write] = AL
    88/copy-byte                    1/mod/*+disp8   4/rm32/sib    7/base/EDI  3/index/EBX   .           0/r32/AL    0xc/disp8       .                 # copy AL to *(EDI+EBX+12)
    # ++out->write
    43/increment-EBX
    # ++in
    41/increment-ECX
    eb/jump  $write-slice:loop/disp8
$write-slice:loop-end:
    # persist out->write
    89/copy                         0/mod/indirect  7/rm32/EDI    .           .             .           3/r32/EBX   .               .                 # copy EBX to *EDI
$write-slice:end:
    # . restore registers
    5f/pop-to-EDI
    5e/pop-to-ESI
    5b/pop-to-EBX
    5a/pop-to-EDX
    59/pop-to-ECX
    58/pop-to-EAX
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

$write-slice:abort:
    # . _write(2/stderr, error)
    # . . push args
    68/push  "write-slice: out of space"/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-write-slice:
    # . 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
    # (EAX..ECX) = "Abc"
    b8/copy-to-EAX  "Abc"/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
    # write-slice(_test-stream, slice)
    # . . push args
    51/push-ECX
    68/push  _test-stream/imm32
    # . . call
    e8/call  write-slice/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # check-stream-equal(_test-stream, "Abc", msg)
    # . . push args
    68/push  "F - test-write-slice"/imm32
    68/push  "Abc"/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  check-stream-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

# write a slice to a buffered-file
write-slice-buffered:  # out : (address buffered-file), s : (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
    52/push-EDX
    53/push-EBX
    56/push-ESI
    57/push-EDI
    # ESI = s
    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   0xc/disp8       .                 # copy *(EBP+12) to ESI
    # curr/ECX = s->start
    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           1/r32/ECX   .               .                 # copy *ESI to ECX
    # max/ESI = s->end
    8b/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           6/r32/ESI   4/disp8         .                 # copy *(ESI+4) to ESI
    # EDI = out
    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .                         7/r32/EDI   8/disp8         .                 # copy *(EBP+8) to EDI
    # EDX = out->length
    8b/copy                         1/mod/*+disp8   7/rm32/EDI    .           .             .           2/r32/EDX   0xc/disp8       .                 # copy *(EDI+12) to EDX
    # EBX = out->write
    8b/copy                         1/mod/*+disp8   7/rm32/EDI    .           .             .           3/r32/EBX   4/disp8         .                 # copy *(EDI+4) to EBX
$write-slice-buffered:loop:
    # if (curr >= max) break
    39/compare                      3/mod/direct    1/rm32/ECX    .           .             .           6/r32/ESI   .               .                 # compare ECX with ESI
    73/jump-if-greater-or-equal-unsigned  $write-slice-buffered:loop-end/disp8
    # if (out->write >= out->length) flush and clear out's stream
    39/compare                      3/mod/direct    3/rm32/EBX    .           .             .           2/r32/EDX   .               .                 # compare EBX with EDX
    7c/jump-if-lesser  $write-slice-buffered:to-stream/disp8
    # . persist out->write
    89/copy                         1/mod/*+disp8   7/rm32/EDI    .           .             .           3/r32/EBX   4/disp8         .                 # copy EBX to *(EDI+4)
    # . flush(out)
    # . . push args
    57/push-EDI
    # . . call
    e8/call  flush/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
    # . clear-stream(stream = out+4)
    # . . push args
    8d/copy-address                 1/mod/*+disp8   7/rm32/EDI    .           .             .           0/r32/EAX   4/disp8         .                 # copy EDI+4 to EAX
    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
    # . out->write must now be 0; update its cache at EBX
    31/xor                          3/mod/direct    3/rm32/EBX    .           .             .           3/r32/EBX   .               .                 # clear EBX
$write-slice-buffered:to-stream:
    # out->data[out->write] = *in
    # . AL = *in
    31/xor                          3/mod/direct    0/rm32/EAX    .           .             .           0/r32/EAX   .               .                 # clear EAX
    8a/copy-byte                    0/mod/indirect  1/rm32/ECX    .           .             .           0/r32/AL    .               .                 # copy byte at *ECX to AL
    # . out->data[out->write] = AL
    88/copy-byte                    1/mod/*+disp8   4/rm32/sib    7/base/EDI  3/index/EBX   .           0/r32/AL    0x10/disp8      .                 # copy AL to *(EDI+EBX+16)
    # ++out->write
    43/increment-EBX
    # ++in
    41/increment-ECX
    eb/jump  $write-slice-buffered:loop/disp8
$write-slice-buffered:loop-end:
    # persist necessary variables from registers
    89/copy                         1/mod/*+disp8   7/rm32/EDI    .           .             .           3/r32/EBX   4/disp8         .                 # copy EBX to *(EDI+4)
$write-slice-buffered:end:
    # . restore registers
    5f/pop-to-EDI
    5e/pop-to-ESI
    5b/pop-to-EBX
    5a/pop-to-EDX
    59/pop-to-ECX
    58/pop-to-EAX
    # . epilog
    89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
    5d/pop-to-EBP
    c3/return

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

# copy a slice into a new (dynamically allocated) string
slice-to-string:  # ad : (address allocation-descriptor), in : (address slice) -> out/EAX : (address array)
    # . 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
    53/push-EBX
    56/push-ESI
    # ESI = in
    8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   0xc/disp8       .                 # copy *(EBP+12) to ESI
    # curr/EDX = in->start
    8b/copy                         0/mod/indirect  6/rm32/ESI    .           .             .           2/r32/EDX   .               .                 # copy *ESI to EDX
    # max/EBX = in->end
    8b/copy                         1/mod/*+disp8   6/rm32/ESI    .           .             .           3/r32/EBX   4/disp8         .                 # copy *(ESI+4) to EBX
    # size/ECX = max - curr + 4  # total size of output string (including the initial length)
    89/copy                         3/mod/direct    1/rm32/ECX    .           .             .           3/r32/EBX   .               .                 # copy EBX to ECX
    29/subtract                     3/mod/direct    1/rm32/ECX    .           .             .           2/r32/EDX   .               .                 # subtract EDX from ECX
    81          0/subop/add         3/mod/direct    1/rm32/ECX    .           .             .           .           .               4/imm32           # add to ECX
    # out/EAX = allocate(ad, size)
    # . . push args
    51/push-ECX
    ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
    # . . call
    e8/call  allocate/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # if (EAX == 0) abort
    3d/compare-EAX-and  0/imm32
    74/jump-if-equal  $slice-to-string:abort/disp8
    # *out = size-4
    89/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy ECX to *EAX
    81          5/subop/subtract    0/mod/indirect  0/rm32/EAX    .           .             .           .           .               4/imm32           # subtract 4 from *EAX
    # save out
    50/push-EAX
    # EAX = _append-4(EAX+4, EAX+size, curr, max)  # clobbering ECX
    # . . push args
    53/push-EBX
    52/push-EDX
    # . . push EAX+size (clobbering ECX)
    01/add                          3/mod/direct    1/rm32/ECX    .           .             .           0/r32/EAX   .               .                 # add EAX to ECX
    51/push-ECX
    # . . push EAX+4 (clobbering EAX)
    81          0/subop/add         3/mod/direct    0/rm32/EAX    .           .             .           .           .               4/imm32           # add to EAX
    50/push-EAX
    # . . call
    e8/call  _append-4/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
    # restore out (assumes _append-4 can't error)
    58/pop-to-EAX
$slice-to-string:end:
    # . restore registers
    5e/pop-to-ESI
    5b/pop-to-EBX
    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

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

test-slice-to-string:
    # . prolog
    55/push-EBP
    89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
    # var heap/EDX : (address allocation-descriptor) = {0, 0}
    68/push  0/imm32/limit
    68/push  0/imm32/curr
    89/copy                         3/mod/direct    2/rm32/EDX    .           .             .           4/r32/ESP   .               .                 # copy ESP to EDX
    # heap = new-segment(512)
    # . . push args
    52/push-EDX
    68/push  0x200/imm32
    # . . call
    e8/call  new-segment/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
    # (EAX..ECX) = "Abc"
    b8/copy-to-EAX  "Abc"/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
    # EAX = slice-to-string(heap, slice)
    # . . push args
    51/push-ECX
    52/push-EDX
    # . . call
    e8/call  slice-to-string/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
#?     # dump word-slice {{{
#?     # . write(2/stderr, "AA: ")
#?     # . . push args
#?     68/push  "AA: "/imm32
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
#?     # . write(2/stderr, EAX)
#?     # . . push args
#?     50/push-EAX
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
#?     # . write(2/stderr, "$\n")
#?     # . . push args
#?     68/push  "$\n"/imm32
#?     68/push  2/imm32/stderr
#?     # . . call
#?     e8/call  write/disp32
#?     # . . discard args
#?     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
#?     # }}}
    # EAX = string-equal?(EAX, "Abc")
    # . . push args
    68/push  "Abc"/imm32
    50/push-EAX
    # . . call
    e8/call  string-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-slice-to-string"/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

# . . vim:nowrap:textwidth=0