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# Tokenize by whitespace.
== 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
# (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
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-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-word:check-for-comment/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-word:end/disp8
$next-word:check-for-comment:
# out->start = &line->data[line->read]
8b/copy 1/mod/*+disp8 6/rm32/esi . . . 1/r32/ecx 4/disp8 . # copy *(esi+4) to ecx
8d/copy-address 1/mod/*+disp8 4/rm32/sib 6/base/esi 1/index/ecx . 0/r32/eax 0xc/disp8 . # copy esi+ecx+12 to eax
89/copy 0/mod/indirect 7/rm32/edi . . . 0/r32/eax . . # copy eax to *edi
# if (line->data[line->read] == '#') out->end = &line->data[line->write]), skip rest of stream and return
# . eax = line->data[line->read]
31/xor 3/mod/direct 0/rm32/eax . . . 0/r32/eax . . # clear eax
8a/copy-byte 1/mod/*+disp8 4/rm32/sib 6/base/esi 1/index/ecx . 0/r32/AL 0xc/disp8 . # copy byte at *(esi+ecx+12) to AL
# . compare
3d/compare-eax-and 0x23/imm32/pound
75/jump-if-!= $next-word:regular-word/disp8
$next-word:comment:
# . out->end = &line->data[line->write]
8b/copy 0/mod/indirect 6/rm32/esi . . . 0/r32/eax . . # copy *esi to eax
8d/copy-address 1/mod/*+disp8 4/rm32/sib 6/base/esi 0/index/eax . 0/r32/eax 0xc/disp8 . # copy esi+eax+12 to eax
89/copy 1/mod/*+disp8 7/rm32/edi . . . 0/r32/eax 4/disp8 . # copy eax to *(edi+4)
# . line->read = line->write
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
$next-word:regular-word:
# otherwise skip-chars-not-matching-whitespace(line) # including trailing newline
# . . push args
ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 8/disp8 . # push *(ebp+8)
# . . call
e8/call skip-chars-not-matching-whitespace/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# out->end = &line->data[line->read]
8b/copy 1/mod/*+disp8 6/rm32/esi . . . 1/r32/ecx 4/disp8 . # copy *(esi+4) to ecx
8d/copy-address 1/mod/*+disp8 4/rm32/sib 6/base/esi 1/index/ecx . 0/r32/eax 0xc/disp8 . # copy esi+ecx+12 to eax
89/copy 1/mod/*+disp8 7/rm32/edi . . . 0/r32/eax 4/disp8 . # copy eax to *(edi+4)
$next-word:end:
# . restore registers
5f/pop-to-edi
5e/pop-to-esi
59/pop-to-ecx
58/pop-to-eax
# . epilogue
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
5d/pop-to-ebp
c3/return
test-next-word:
# . prologue
55/push-ebp
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
# setup
# . clear-stream(_test-stream)
# . . push args
68/push _test-stream/imm32
# . . call
e8/call clear-stream/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# var slice/ecx: slice
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
# write(_test-stream, " ab")
# . . push args
68/push " ab"/imm32
68/push _test-stream/imm32
# . . call
e8/call write/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
# next-word(_test-stream, slice)
# . . push args
51/push-ecx
68/push _test-stream/imm32
# . . call
e8/call next-word/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
# check-ints-equal(slice->start - _test-stream->data, 2, msg)
# . check-ints-equal(slice->start - _test-stream, 14, msg)
# . . push args
68/push "F - test-next-word: start"/imm32
68/push 0xe/imm32
# . . push slice->start - _test-stream
8b/copy 0/mod/indirect 1/rm32/ecx . . . 0/r32/eax . . # copy *ecx to eax
81 5/subop/subtract 3/mod/direct 0/rm32/eax . . . . . _test-stream/imm32 # subtract from eax
50/push-eax
# . . call
e8/call check-ints-equal/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
# check-ints-equal(slice->end - _test-stream->data, 4, msg)
# . check-ints-equal(slice->end - _test-stream, 16, msg)
# . . push args
68/push "F - test-next-word: end"/imm32
68/push 0x10/imm32
# . . push slice->end - _test-stream
8b/copy 1/mod/*+disp8 1/rm32/ecx . . . 0/r32/eax 4/disp8 . # copy *(ecx+4) to eax
81 5/subop/subtract 3/mod/direct 0/rm32/eax . . . . . _test-stream/imm32 # subtract from eax
50/push-eax
# . . call
e8/call check-ints-equal/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
# . epilogue
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
5d/pop-to-ebp
c3/return
test-next-word-returns-whole-comment:
# . prologue
55/push-ebp
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
# setup
# . clear-stream(_test-stream)
# . . push args
68/push _test-stream/imm32
# . . call
e8/call clear-stream/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# var slice/ecx: slice
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
# write(_test-stream, " # a")
# . . push args
68/push " # a"/imm32
68/push _test-stream/imm32
# . . call
e8/call write/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
# next-word(_test-stream, slice)
# . . push args
51/push-ecx
68/push _test-stream/imm32
# . . call
e8/call next-word/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
# check-ints-equal(slice->start - _test-stream->data, 2, msg)
# . check-ints-equal(slice->start - _test-stream, 14, msg)
# . . push args
68/push "F - test-next-word-returns-whole-comment: start"/imm32
68/push 0xe/imm32
# . . push slice->start - _test-stream
8b/copy 0/mod/indirect 1/rm32/ecx . . . 0/r32/eax . . # copy *ecx to eax
81 5/subop/subtract 3/mod/direct 0/rm32/eax . . . . . _test-stream/imm32 # subtract from eax
50/push-eax
# . . call
e8/call check-ints-equal/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
# check-ints-equal(slice->end - _test-stream->data, 5, msg)
# . check-ints-equal(slice->end - _test-stream, 17, msg)
# . . push args
68/push "F - test-next-word-returns-whole-comment: end"/imm32
68/push 0x11/imm32
# . . push slice->end - _test-stream
8b/copy 1/mod/*+disp8 1/rm32/ecx . . . 0/r32/eax 4/disp8 . # copy *(ecx+4) to eax
81 5/subop/subtract 3/mod/direct 0/rm32/eax . . . . . _test-stream/imm32 # subtract from eax
50/push-eax
# . . call
e8/call check-ints-equal/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
# . epilogue
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
5d/pop-to-ebp
c3/return
test-next-word-returns-empty-string-on-eof:
# . prologue
55/push-ebp
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
# setup
# . clear-stream(_test-stream)
# . . push args
68/push _test-stream/imm32
# . . call
e8/call clear-stream/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# var slice/ecx: slice
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
# write nothing to _test-stream
# next-word(_test-stream, slice)
# . . push args
51/push-ecx
68/push _test-stream/imm32
# . . call
e8/call next-word/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
# check-ints-equal(slice->end - slice->start, 0, msg)
# . . push args
68/push "F - test-next-word-returns-empty-string-on-eof"/imm32
68/push 0/imm32
# . . push slice->end - slice->start
8b/copy 1/mod/*+disp8 1/rm32/ecx . . . 0/r32/eax 4/disp8 . # copy *(ecx+4) to eax
2b/subtract 0/mod/indirect 1/rm32/ecx . . . 0/r32/eax . . # subtract *ecx from eax
50/push-eax
# . . call
e8/call check-ints-equal/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
# . epilogue
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
5d/pop-to-ebp
c3/return
test-next-word-returns-empty-string-on-newline:
# . prologue
55/push-ebp
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
# setup
# . clear-stream(_test-stream)
# . . push args
68/push _test-stream/imm32
# . . call
e8/call clear-stream/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# var slice/ecx: slice
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
# write some whitespace and a newline
# . . push args
68/push " \n"/imm32
68/push _test-stream/imm32
# . . call
e8/call write/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
# next-word(_test-stream, slice)
# . . push args
51/push-ecx
68/push _test-stream/imm32
# . . call
e8/call next-word/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
# check-ints-equal(slice->end - slice->start, 0, msg)
# . . push args
68/push "F - test-next-word-returns-empty-string-on-newline"/imm32
68/push 0/imm32
# . . push slice->end - slice->start
8b/copy 1/mod/*+disp8 1/rm32/ecx . . . 0/r32/eax 4/disp8 . # copy *(ecx+4) to eax
2b/subtract 0/mod/indirect 1/rm32/ecx . . . 0/r32/eax . . # subtract *ecx from eax
50/push-eax
# . . call
e8/call check-ints-equal/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp
# . epilogue
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
|