diff options
Diffstat (limited to 'subx/apps/subx-common.subx')
| -rw-r--r-- | subx/apps/subx-common.subx | 251 |
1 files changed, 251 insertions, 0 deletions
diff --git a/subx/apps/subx-common.subx b/subx/apps/subx-common.subx new file mode 100644 index 00000000..49d6c4b6 --- /dev/null +++ b/subx/apps/subx-common.subx @@ -0,0 +1,251 @@ +# some common helpers shared by phases of the SubX converter + +== 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 +# return empty string on reaching end of file +next-word: # line : (address stream byte), out : (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 + 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(line, ' ') + # . . push args + 68/push 0x20/imm32/space + ff 6/subop/push 1/mod/*+disp8 5/rm32/EBP . . . . 8/disp8 . # push *(EBP+8) + # . . call + e8/call skip-chars-matching/disp32 + # . . discard args + 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/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-lesser $next-word:check1/disp8 + # . return out = {0, 0} + 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:check1: + # 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-not-equal $next-word:not-comment/disp8 + # . 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 + 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:not-comment: + # 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 + # . epilog + 89/copy 3/mod/direct 4/rm32/ESP . . . 5/r32/EBP . . # copy EBP to ESP + 5d/pop-to-EBP + c3/return + +test-next-word: + # . 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 + # var slice/ECX = {0, 0} + 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 + # . epilog + 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: + # . 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 + # var slice/ECX = {0, 0} + 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 + # . epilog + 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: + # . 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 + # var slice/ECX = {0, 0} + 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 + # . epilog + 89/copy 3/mod/direct 4/rm32/ESP . . . 5/r32/EBP . . # copy EBP to ESP + 5d/pop-to-EBP + c3/return |