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authorKartik Agaram <vc@akkartik.com>2020-07-05 12:13:28 -0700
committerKartik Agaram <vc@akkartik.com>2020-07-05 12:13:28 -0700
commitc09c91e185aad8e01b570c2569e13c1e429d2f99 (patch)
tree52a5ae1494ad5b7b2319411815dc45510e761c24 /128subx-words.subx
parentf2c5b05374186f9422cfdaf1ada096e39ac91a8b (diff)
downloadmu-c09c91e185aad8e01b570c2569e13c1e429d2f99.tar.gz
6612 - reorganize layers
Diffstat (limited to '128subx-words.subx')
-rw-r--r--128subx-words.subx623
1 files changed, 623 insertions, 0 deletions
diff --git a/128subx-words.subx b/128subx-words.subx
new file mode 100644
index 00000000..6f93e421
--- /dev/null
+++ b/128subx-words.subx
@@ -0,0 +1,623 @@
+# Helpers for parsing SubX words, with their rules for hex, labels and metadata.
+
+== 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
+
+has-metadata?:  # word: (addr slice), s: (addr string) -> eax: boolean
+    # pseudocode:
+    #   var twig: &slice = next-token-from-slice(word->start, word->end, '/')  # skip name
+    #   curr = twig->end
+    #   while true
+    #     twig = next-token-from-slice(curr, word->end, '/')
+    #     if (twig.empty()) break
+    #     if (slice-equal?(twig, s)) return true
+    #     curr = twig->end
+    #   return false
+    # . prologue
+    55/push-ebp
+    89/copy                         3/mod/direct    5/rm32/ebp    .           .             .           4/r32/esp   .               .                 # copy esp to ebp
+    # . save registers
+    51/push-ecx
+    52/push-edx
+    56/push-esi
+    57/push-edi
+    # esi = word
+    8b/copy                         1/mod/*+disp8   5/rm32/ebp    .           .             .           6/r32/esi   8/disp8         .                 # copy *(ebp+8) to esi
+    # var edx: (addr byte) = word->end
+    8b/copy                         1/mod/*+disp8   6/rm32/esi    .           .             .           2/r32/edx   4/disp8         .                 # copy *(esi+4) to edx
+    # var twig/edi: slice
+    68/push  0/imm32/end
+    68/push  0/imm32/start
+    89/copy                         3/mod/direct    7/rm32/edi    .           .             .           4/r32/esp   .               .                 # copy esp to edi
+    # next-token-from-slice(word->start, word->end, '/', twig)
+    # . . push args
+    57/push-edi
+    68/push  0x2f/imm32/slash
+    52/push-edx
+    ff          6/subop/push        0/mod/indirect  6/rm32/esi    .           .             .           .           .               .                 # push *esi
+    # . . call
+    e8/call  next-token-from-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0x10/imm32        # add to esp
+$has-metadata?:loop:
+    # next-token-from-slice(curr, word->end, '/', twig)
+    # . . push args
+    57/push-edi
+    68/push  0x2f/imm32/slash
+    52/push-edx
+    ff          6/subop/push        1/mod/*+disp8   7/rm32/edi    .           .             .           .           4/disp8         .                 # push *(edi+4)
+    # . . call
+    e8/call  next-token-from-slice/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0x10/imm32        # add to esp
+    # if (slice-empty?(twig)) return false
+    # . eax = slice-empty?(twig)
+    # . . push args
+    57/push-edi
+    # . . call
+    e8/call  slice-empty?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
+    # . if (eax != false) return false
+    3d/compare-eax-and  0/imm32/false
+    75/jump-if-!=  $has-metadata?:false/disp8
+    # if (slice-equal?(twig, s)) return true
+    # . eax = slice-equal?(twig, s)
+    # . . push args
+    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           0xc/disp8       .                 # push *(ebp+12)
+    57/push-edi
+    # . . call
+    e8/call  slice-equal?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
+    # . if (eax != false) return true
+    3d/compare-eax-and  0/imm32/false
+    # eax already contains true
+    75/jump-if-!=  $has-metadata?:end/disp8
+    eb/jump  $has-metadata?:loop/disp8
+$has-metadata?:false:
+    b8/copy-to-eax  0/imm32/false
+$has-metadata?:end:
+    # . reclaim locals
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
+    # . restore registers
+    5f/pop-to-edi
+    5e/pop-to-esi
+    5a/pop-to-edx
+    59/pop-to-ecx
+    # . epilogue
+    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
+    5d/pop-to-ebp
+    c3/return
+
+test-has-metadata-true:
+    # . prologue
+    55/push-ebp
+    89/copy                         3/mod/direct    5/rm32/ebp    .           .             .           4/r32/esp   .               .                 # copy esp to ebp
+    # (eax..ecx) = "ab/imm32"
+    b8/copy-to-eax  "ab/imm32"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/eax    .           .             .           1/r32/ecx   .               .                 # copy *eax to ecx
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/eax  1/index/ecx   .           1/r32/ecx   4/disp8         .                 # copy eax+ecx+4 to ecx
+    05/add-to-eax  4/imm32
+    # var in/esi: slice = {eax, ecx}
+    51/push-ecx
+    50/push-eax
+    89/copy                         3/mod/direct    6/rm32/esi    .           .             .           4/r32/esp   .               .                 # copy esp to esi
+    # eax = has-metadata?(esi, "imm32")
+    # . . push args
+    68/push  "imm32"/imm32
+    56/push-esi
+    # . . call
+    e8/call  has-metadata?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
+    # check-ints-equal(eax, 1, msg)
+    # . . push args
+    68/push  "F - test-has-metadata-true"/imm32
+    68/push  1/imm32/true
+    50/push-eax
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
+    # . epilogue
+    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
+    5d/pop-to-ebp
+    c3/return
+
+test-has-metadata-false:
+    # . prologue
+    55/push-ebp
+    89/copy                         3/mod/direct    5/rm32/ebp    .           .             .           4/r32/esp   .               .                 # copy esp to ebp
+    # (eax..ecx) = "ab/c"
+    b8/copy-to-eax  "ab/c"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/eax    .           .             .           1/r32/ecx   .               .                 # copy *eax to ecx
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/eax  1/index/ecx   .           1/r32/ecx   4/disp8         .                 # copy eax+ecx+4 to ecx
+    05/add-to-eax  4/imm32
+    # var in/esi: slice = {eax, ecx}
+    51/push-ecx
+    50/push-eax
+    89/copy                         3/mod/direct    6/rm32/esi    .           .             .           4/r32/esp   .               .                 # copy esp to esi
+    # eax = has-metadata?(esi, "d")
+    # . . push args
+    68/push  "d"/imm32
+    56/push-esi
+    # . . call
+    e8/call  has-metadata?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
+    # check-ints-equal(eax, 0, msg)
+    # . . push args
+    68/push  "F - test-has-metadata-false"/imm32
+    68/push  0/imm32/false
+    50/push-eax
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
+    # . epilogue
+    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
+    5d/pop-to-ebp
+    c3/return
+
+test-has-metadata-ignore-name:
+    # . prologue
+    55/push-ebp
+    89/copy                         3/mod/direct    5/rm32/ebp    .           .             .           4/r32/esp   .               .                 # copy esp to ebp
+    # (eax..ecx) = "a/b"
+    b8/copy-to-eax  "a/b"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/eax    .           .             .           1/r32/ecx   .               .                 # copy *eax to ecx
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/eax  1/index/ecx   .           1/r32/ecx   4/disp8         .                 # copy eax+ecx+4 to ecx
+    05/add-to-eax  4/imm32
+    # var in/esi: slice = {eax, ecx}
+    51/push-ecx
+    50/push-eax
+    89/copy                         3/mod/direct    6/rm32/esi    .           .             .           4/r32/esp   .               .                 # copy esp to esi
+    # eax = has-metadata?(esi, "a")
+    # . . push args
+    68/push  "a"/imm32
+    56/push-esi
+    # . . call
+    e8/call  has-metadata?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
+    # check-ints-equal(eax, 0, msg)
+    # . . push args
+    68/push  "F - test-has-metadata-ignore-name"/imm32
+    68/push  0/imm32/false
+    50/push-eax
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
+    # . epilogue
+    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
+    5d/pop-to-ebp
+    c3/return
+
+test-has-metadata-multiple-true:
+    # . prologue
+    55/push-ebp
+    89/copy                         3/mod/direct    5/rm32/ebp    .           .             .           4/r32/esp   .               .                 # copy esp to ebp
+    # (eax..ecx) = "a/b/c"
+    b8/copy-to-eax  "a/b/c"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/eax    .           .             .           1/r32/ecx   .               .                 # copy *eax to ecx
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/eax  1/index/ecx   .           1/r32/ecx   4/disp8         .                 # copy eax+ecx+4 to ecx
+    05/add-to-eax  4/imm32
+    # var in/esi: slice = {eax, ecx}
+    51/push-ecx
+    50/push-eax
+    89/copy                         3/mod/direct    6/rm32/esi    .           .             .           4/r32/esp   .               .                 # copy esp to esi
+    # eax = has-metadata?(esi, "c")
+    # . . push args
+    68/push  "c"/imm32
+    56/push-esi
+    # . . call
+    e8/call  has-metadata?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
+    # check-ints-equal(eax, 1, msg)
+    # . . push args
+    68/push  "F - test-has-metadata-multiple-true"/imm32
+    68/push  1/imm32/true
+    50/push-eax
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
+    # . epilogue
+    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
+    5d/pop-to-ebp
+    c3/return
+
+test-has-metadata-multiple-false:
+    # . prologue
+    55/push-ebp
+    89/copy                         3/mod/direct    5/rm32/ebp    .           .             .           4/r32/esp   .               .                 # copy esp to ebp
+    # (eax..ecx) = "a/b/c"
+    b8/copy-to-eax  "a/b/c"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/eax    .           .             .           1/r32/ecx   .               .                 # copy *eax to ecx
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/eax  1/index/ecx   .           1/r32/ecx   4/disp8         .                 # copy eax+ecx+4 to ecx
+    05/add-to-eax  4/imm32
+    # var in/esi: slice = {eax, ecx}
+    51/push-ecx
+    50/push-eax
+    89/copy                         3/mod/direct    6/rm32/esi    .           .             .           4/r32/esp   .               .                 # copy esp to esi
+    # eax = has-metadata?(esi, "d")
+    # . . push args
+    68/push  "d"/imm32
+    56/push-esi
+    # . . call
+    e8/call  has-metadata?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
+    # check-ints-equal(eax, 0, msg)
+    # . . push args
+    68/push  "F - test-has-metadata-multiple-false"/imm32
+    68/push  0/imm32/false
+    50/push-eax
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
+    # . epilogue
+    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
+    5d/pop-to-ebp
+    c3/return
+
+# conditions for 'valid' names that are not at risk of looking like hex numbers
+# keep in sync with the rules in labels.cc
+#: - if it starts with a digit, it's treated as a number. If it can't be
+#:   parsed as hex it will raise an error.
+#: - if it starts with '-' it's treated as a number.
+#: - if it starts with '0x' it's treated as a number. (redundant)
+#: - if it's two characters long, it can't be a name. Either it's a hex
+#:   byte, or it raises an error.
+is-valid-name?:  # in: (addr slice) -> eax: boolean
+    # . prologue
+    55/push-ebp
+    89/copy                         3/mod/direct    5/rm32/ebp    .           .             .           4/r32/esp   .               .                 # copy esp to ebp
+    # . save registers
+    51/push-ecx
+    56/push-esi
+    # esi = in
+    8b/copy                         1/mod/*+disp8   5/rm32/ebp    .           .             .           6/r32/esi   8/disp8         .                 # copy *(ebp+8) to esi
+    # var start/ecx: (addr byte) = in->start
+    8b/copy                         0/mod/indirect  6/rm32/esi    .           .             .           1/r32/ecx   .               .                 # copy *esi to ecx
+$is-valid-name?:check0:
+    # if (start >= in->end) return false
+    3b/compare                      1/mod/*+disp8   6/rm32/esi    .           .             .           1/r32/ecx   4/disp8         .                 # compare ecx with *(esi+4)
+    73/jump-if-addr>=  $is-valid-name?:false/disp8
+$is-valid-name?:check1:
+    # var len/eax: int = in->end - start
+    8b/copy                         1/mod/*+disp8   6/rm32/esi    .           .             .           0/r32/eax   4/disp8         .                 # copy *(esi+4) to eax
+    29/subtract                     3/mod/direct    0/rm32/eax    .           .             .           1/r32/ecx   .               .                 # subtract ecx from eax
+    # if (eax == 2) return false
+    3d/compare-eax-and  2/imm32
+    74/jump-if-=  $is-valid-name?:false/disp8
+$is-valid-name?:check2:
+    # var c/eax: (addr byte) = *start
+    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
+    # if (c == "-") return false
+    3d/compare-eax-and  2d/imm32/-
+    74/jump-if-=  $is-valid-name?:false/disp8
+$is-valid-name?:check3a:
+    # if (c < "0") return true
+    3d/compare-eax-with  30/imm32/0
+    7c/jump-if-<  $is-valid-name?:true/disp8
+$is-valid-name?:check3b:
+    # if (c > "9") return true
+    3d/compare-eax-with  39/imm32/9
+    7f/jump-if->  $is-valid-name?:true/disp8
+$is-valid-name?:false:
+    # return false
+    b8/copy-to-eax  0/imm32/false
+    eb/jump  $is-valid-name?:end/disp8
+$is-valid-name?:true:
+    # return true
+    b8/copy-to-eax  1/imm32/true
+$is-valid-name?:end:
+    # . restore registers
+    5e/pop-to-esi
+    59/pop-to-ecx
+    # . epilogue
+    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
+    5d/pop-to-ebp
+    c3/return
+
+test-is-valid-name-digit-prefix:
+    # . prologue
+    55/push-ebp
+    89/copy                         3/mod/direct    5/rm32/ebp    .           .             .           4/r32/esp   .               .                 # copy esp to ebp
+    # (eax..ecx) = "34"
+    b8/copy-to-eax  "34"/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: slice = {eax, ecx}
+    51/push-ecx
+    50/push-eax
+    89/copy                         3/mod/direct    1/rm32/ecx    .           .             .           4/r32/esp   .               .                 # copy esp to ecx
+    # eax = is-valid-name?(slice)
+    # . . push args
+    51/push-ecx
+    # . . call
+    e8/call  is-valid-name?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
+    # check-ints-equal(eax, 0, msg)
+    # . . push args
+    68/push  "F - test-is-valid-name-digit-prefix"/imm32
+    68/push  0/imm32/false
+    50/push-eax
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
+    # . epilogue
+    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
+    5d/pop-to-ebp
+    c3/return
+
+test-is-valid-name-negative-prefix:
+    # . prologue
+    55/push-ebp
+    89/copy                         3/mod/direct    5/rm32/ebp    .           .             .           4/r32/esp   .               .                 # copy esp to ebp
+    # (eax..ecx) = "-0x34"
+    b8/copy-to-eax  "-0x34"/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: slice = {eax, ecx}
+    51/push-ecx
+    50/push-eax
+    89/copy                         3/mod/direct    1/rm32/ecx    .           .             .           4/r32/esp   .               .                 # copy esp to ecx
+    # eax = is-valid-name?(slice)
+    # . . push args
+    51/push-ecx
+    # . . call
+    e8/call  is-valid-name?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
+    # check-ints-equal(eax, 0, msg)
+    # . . push args
+    68/push  "F - test-is-valid-name-negative-prefix"/imm32
+    68/push  0/imm32/false
+    50/push-eax
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
+    # . epilogue
+    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
+    5d/pop-to-ebp
+    c3/return
+
+test-is-valid-name-0x-prefix:
+    # . prologue
+    55/push-ebp
+    89/copy                         3/mod/direct    5/rm32/ebp    .           .             .           4/r32/esp   .               .                 # copy esp to ebp
+    # (eax..ecx) = "0x34"
+    b8/copy-to-eax  "0x34"/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: slice = {eax, ecx}
+    51/push-ecx
+    50/push-eax
+    89/copy                         3/mod/direct    1/rm32/ecx    .           .             .           4/r32/esp   .               .                 # copy esp to ecx
+    # eax = is-valid-name?(slice)
+    # . . push args
+    51/push-ecx
+    # . . call
+    e8/call  is-valid-name?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
+    # check-ints-equal(eax, 0, msg)
+    # . . push args
+    68/push  "F - test-is-valid-name-0x-prefix"/imm32
+    68/push  0/imm32/false
+    50/push-eax
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
+    # . epilogue
+    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
+    5d/pop-to-ebp
+    c3/return
+
+test-is-valid-name-starts-with-pre-digit:
+    # . prologue
+    55/push-ebp
+    89/copy                         3/mod/direct    5/rm32/ebp    .           .             .           4/r32/esp   .               .                 # copy esp to ebp
+    # (eax..ecx) = "/03"
+    b8/copy-to-eax  "/03"/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: slice = {eax, ecx}
+    51/push-ecx
+    50/push-eax
+    89/copy                         3/mod/direct    1/rm32/ecx    .           .             .           4/r32/esp   .               .                 # copy esp to ecx
+    # eax = is-valid-name?(slice)
+    # . . push args
+    51/push-ecx
+    # . . call
+    e8/call  is-valid-name?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
+    # check-ints-equal(eax, 1, msg)
+    # . . push args
+    68/push  "F - test-is-valid-name-starts-with-pre-digit"/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
+    # . epilogue
+    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
+    5d/pop-to-ebp
+    c3/return
+
+test-is-valid-name-starts-with-post-digit:
+    # . prologue
+    55/push-ebp
+    89/copy                         3/mod/direct    5/rm32/ebp    .           .             .           4/r32/esp   .               .                 # copy esp to ebp
+    # (eax..ecx) = "q34"
+    b8/copy-to-eax  "q34"/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: slice = {eax, ecx}
+    51/push-ecx
+    50/push-eax
+    89/copy                         3/mod/direct    1/rm32/ecx    .           .             .           4/r32/esp   .               .                 # copy esp to ecx
+    # eax = is-valid-name?(slice)
+    # . . push args
+    51/push-ecx
+    # . . call
+    e8/call  is-valid-name?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
+    # check-ints-equal(eax, 1, msg)
+    # . . push args
+    68/push  "F - test-is-valid-name-starts-with-post-digit"/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
+    # . epilogue
+    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
+    5d/pop-to-ebp
+    c3/return
+
+test-is-valid-name-starts-with-digit:
+    # . prologue
+    55/push-ebp
+    89/copy                         3/mod/direct    5/rm32/ebp    .           .             .           4/r32/esp   .               .                 # copy esp to ebp
+    # (eax..ecx) = "0x34"
+    b8/copy-to-eax  "0x34"/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: slice = {eax, ecx}
+    51/push-ecx
+    50/push-eax
+    89/copy                         3/mod/direct    1/rm32/ecx    .           .             .           4/r32/esp   .               .                 # copy esp to ecx
+    # eax = is-valid-name?(slice)
+    # . . push args
+    51/push-ecx
+    # . . call
+    e8/call  is-valid-name?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
+    # check-ints-equal(eax, 0, msg)
+    # . . push args
+    68/push  "F - test-is-valid-name-starts-with-digit"/imm32
+    68/push  0/imm32/false
+    50/push-eax
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
+    # . epilogue
+    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
+    5d/pop-to-ebp
+    c3/return
+
+is-label?: # word: (addr slice) -> eax: boolean
+    # . prologue
+    55/push-ebp
+    89/copy                         3/mod/direct    5/rm32/ebp    .           .             .           4/r32/esp   .               .                 # copy esp to ebp
+    # . save registers
+    51/push-ecx
+    # ecx = word
+    8b/copy                         1/mod/*+disp8   5/rm32/ebp    .           .             .           1/r32/ecx   8/disp8         .                 # copy *(ebp+8) to ecx
+    # var end/ecx: (addr byte) = word->end
+    8b/copy                         1/mod/*+disp8   1/rm32/ecx    .           .             .           1/r32/ecx   4/disp8         .                 # copy *(ecx+4) to ecx
+    # return *(end - 1) == ':'
+    # . eax = *(end-1)
+    31/xor                          3/mod/direct    0/rm32/eax    .           .             .           0/r32/eax   .               .                 # clear eax
+    8a/copy-byte                    1/mod/*+disp8   1/rm32/ecx    .           .             .           0/r32/AL    -1/disp8         .                 # copy byte at *(ecx-1) to AL
+    # . return (eax == ':')
+    3d/compare-eax-and  0x3a/imm32/colon
+    b8/copy-to-eax  1/imm32/true
+    74/jump-if-=  $is-label?:end/disp8
+    b8/copy-to-eax  0/imm32/false
+$is-label?:end:
+    # . restore registers
+    59/pop-to-ecx
+    # . epilogue
+    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
+    5d/pop-to-ebp
+    c3/return
+
+test-is-label?:
+    # . prologue
+    55/push-ebp
+    89/copy                         3/mod/direct    5/rm32/ebp    .           .             .           4/r32/esp   .               .                 # copy esp to ebp
+$test-is-label?:true:
+    # (eax..ecx) = "AAA:"
+    b8/copy-to-eax  "AAA:"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/eax    .           .             .           1/r32/ecx   .               .                 # copy *eax to ecx
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/eax  1/index/ecx   .           1/r32/ecx   4/disp8         .                 # copy eax+ecx+4 to ecx
+    05/add-to-eax  4/imm32
+    # var slice/ecx: slice = {eax, ecx}
+    51/push-ecx
+    50/push-eax
+    89/copy                         3/mod/direct    1/rm32/ecx    .           .             .           4/r32/esp   .               .                 # copy esp to ecx
+    # is-label?(slice/ecx)
+    # . . push args
+    51/push-ecx
+    # . . call
+    e8/call  is-label?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
+    # check-ints-equal(eax, 1, msg)
+    # . . push args
+    68/push  "F - test-is-label?:true"/imm32
+    68/push  1/imm32
+    50/push-eax
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
+$test-is-label?:false:
+    # (eax..ecx) = "AAA"
+    b8/copy-to-eax  "AAA"/imm32
+    8b/copy                         0/mod/indirect  0/rm32/eax    .           .             .           1/r32/ecx   .               .                 # copy *eax to ecx
+    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/eax  1/index/ecx   .           1/r32/ecx   4/disp8         .                 # copy eax+ecx+4 to ecx
+    05/add-to-eax  4/imm32
+    # var slice/ecx: slice = {eax, ecx}
+    51/push-ecx
+    50/push-eax
+    89/copy                         3/mod/direct    1/rm32/ecx    .           .             .           4/r32/esp   .               .                 # copy esp to ecx
+    # is-label?(slice/ecx)
+    # . . push args
+    51/push-ecx
+    # . . call
+    e8/call  is-label?/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
+    # check-ints-equal(eax, 0, msg)
+    # . . push args
+    68/push  "F - test-is-label?:false"/imm32
+    68/push  0/imm32
+    50/push-eax
+    # . . call
+    e8/call  check-ints-equal/disp32
+    # . . discard args
+    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
+    # . epilogue
+    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
+    5d/pop-to-ebp
+    c3/return
+
+# . . vim:nowrap:textwidth=0