diff options
Diffstat (limited to '127next-word.subx')
| -rw-r--r-- | 127next-word.subx | 64 |
1 files changed, 63 insertions, 1 deletions
diff --git a/127next-word.subx b/127next-word.subx index 6705437f..5af326d4 100644 --- a/127next-word.subx +++ b/127next-word.subx @@ -5,7 +5,8 @@ # . 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 -# (re)compute the bounds of the next word in the line +# (re)compute the bounds of the next word in the line (surrounded by whitespace, +# treating '#' comments as a single word) # return empty string on reaching end of file next-word: # line: (addr stream byte), out: (addr slice) # . prologue @@ -56,6 +57,7 @@ $next-word:comment: 8d/copy-address 1/mod/*+disp8 4/rm32/sib 6/base/esi 0/index/eax . 0/r32/eax 0xc/disp8 . # copy esi+eax+12 to eax 89/copy 1/mod/*+disp8 7/rm32/edi . . . 0/r32/eax 4/disp8 . # copy eax to *(edi+4) # . line->read = line->write + 8b/copy 0/mod/indirect 6/rm32/esi . . . 0/r32/eax . . # copy *esi to eax 89/copy 1/mod/*+disp8 6/rm32/esi . . . 0/r32/eax 4/disp8 . # copy eax to *(esi+4) # . return eb/jump $next-word:end/disp8 @@ -298,3 +300,63 @@ test-next-word-returns-empty-string-on-newline: 89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp 5d/pop-to-ebp c3/return + +# (re)compute the bounds of the next word in the line (separated by whitespace) +# return empty string on reaching end of file +next-raw-word: # line: (addr stream byte), out: (addr slice) + # . prologue + 55/push-ebp + 89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp + # . save registers + 50/push-eax + 51/push-ecx + 56/push-esi + 57/push-edi + # esi = line + 8b/copy 1/mod/*+disp8 5/rm32/ebp . . . 6/r32/esi 8/disp8 . # copy *(ebp+8) to esi + # edi = out + 8b/copy 1/mod/*+disp8 5/rm32/ebp . . . 7/r32/edi 0xc/disp8 . # copy *(ebp+12) to edi + # skip-chars-matching-whitespace(line) + # . . push args + ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 8/disp8 . # push *(ebp+8) + # . . call + e8/call skip-chars-matching-whitespace/disp32 + # . . discard args + 81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp +$next-raw-word:check0: + # if (line->read >= line->write) clear out and return + # . eax = line->read + 8b/copy 1/mod/*+disp8 6/rm32/esi . . . 0/r32/eax 4/disp8 . # copy *(esi+4) to eax + # . if (eax < line->write) goto next check + 3b/compare 0/mod/indirect 6/rm32/esi . . . 0/r32/eax . . # compare eax with *esi + 7c/jump-if-< $next-raw-word:word-exists/disp8 + # . return out + c7 0/subop/copy 0/mod/direct 7/rm32/edi . . . . . 0/imm32 # copy to *edi + c7 0/subop/copy 1/mod/*+disp8 7/rm32/edi . . . . 4/disp8 0/imm32 # copy to *(edi+4) + eb/jump $next-raw-word:end/disp8 +$next-raw-word:word-exists: + # out->start = &line->data[line->read] + 8b/copy 1/mod/*+disp8 6/rm32/esi . . . 1/r32/ecx 4/disp8 . # copy *(esi+4) to ecx + 8d/copy-address 1/mod/*+disp8 4/rm32/sib 6/base/esi 1/index/ecx . 0/r32/eax 0xc/disp8 . # copy esi+ecx+12 to eax + 89/copy 0/mod/indirect 7/rm32/edi . . . 0/r32/eax . . # copy eax to *edi + # skip-chars-not-matching-whitespace(line) # including trailing newline + # . . push args + ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 8/disp8 . # push *(ebp+8) + # . . call + e8/call skip-chars-not-matching-whitespace/disp32 + # . . discard args + 81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp + # out->end = &line->data[line->read] + 8b/copy 1/mod/*+disp8 6/rm32/esi . . . 1/r32/ecx 4/disp8 . # copy *(esi+4) to ecx + 8d/copy-address 1/mod/*+disp8 4/rm32/sib 6/base/esi 1/index/ecx . 0/r32/eax 0xc/disp8 . # copy esi+ecx+12 to eax + 89/copy 1/mod/*+disp8 7/rm32/edi . . . 0/r32/eax 4/disp8 . # copy eax to *(edi+4) +$next-raw-word:end: + # . restore registers + 5f/pop-to-edi + 5e/pop-to-esi + 59/pop-to-ecx + 58/pop-to-eax + # . epilogue + 89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp + 5d/pop-to-ebp + c3/return |