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| author | Kartik Agaram <vc@akkartik.com> | 2018-09-21 23:34:12 -0700 |
|---|---|---|
| committer | Kartik Agaram <vc@akkartik.com> | 2018-09-21 23:34:12 -0700 |
| commit | e7d9351f52fb3b747760031c77ca117336c08219 (patch) | |
| tree | ec662c7b3af4ecacacbe5b47138773bcbf842bd9 /subx/examples/ex10.subx | |
| parent | d47f3a82786c7d3abdb1001c2562780d0e1fab2e (diff) | |
| download | mu-e7d9351f52fb3b747760031c77ca117336c08219.tar.gz | |
4585
Diffstat (limited to 'subx/examples/ex10.subx')
| -rw-r--r-- | subx/examples/ex10.subx | 72 |
1 files changed, 0 insertions, 72 deletions
diff --git a/subx/examples/ex10.subx b/subx/examples/ex10.subx index 1a426e28..97dd42eb 100644 --- a/subx/examples/ex10.subx +++ b/subx/examples/ex10.subx @@ -26,7 +26,6 @@ # push args 50/push . . . . . . . . # push EAX 53/push . . . . . . . . # push EBX -#? e8/call write_argv_3/disp32 # call e8/call argv_equal/disp32 # exit(EAX) @@ -41,8 +40,6 @@ argv_equal: # (s1, s2) : null-terminated ascii strings -> EAX : boolean # initialize s1 (ECX) and s2 (EDX) 8b/copy 1/mod/*+disp8 4/rm32/sib 4/base/ESP 4/index/none . 1/r32/ECX 8/disp8 . # copy *(ESP+8) to ECX 8b/copy 1/mod/*+disp8 4/rm32/sib 4/base/ESP 4/index/none . 2/r32/EDX 4/disp8 . # copy *(ESP+4) to EDX -#? # i/ESI = 0 -#? be/copy 0/imm32 # copy 0 to ESI # while (true) $argv_loop: # c1/EAX, c2/EBX = *s1, *s2 @@ -50,9 +47,6 @@ $argv_loop: 8a/copy 0/mod/indirect 1/rm32/ECX . . . 0/r32/EAX . . # copy byte at *ECX to lower byte of EAX bb/copy 0/imm32 # clear EBX 8a/copy 0/mod/indirect 2/rm32/EDX . . . 3/r32/EBX . . # copy byte at *EDX to lower byte of EBX -#? # if (i == _) exit(EAX) -#? 81 7/subop 3/mod/direct 6/rm32/ESI 3/imm32 # compare ESI with _ -#? 74/jump-if-equal $exit/disp8 # if (c1 == 0) break 3d/compare . . . . . . . 0/imm32 # compare EAX with 0 74/jump-if-equal $argv_break/disp8 @@ -62,15 +56,7 @@ $argv_loop: # ++s1, ++s2 41/inc-ECX 42/inc-EDX -#? # ++i -#? 46/inc-ESI # end while -#? 68/push X/imm32 -#? e8/call write_stderr/disp32 -#? 81 0/subop/add 3/mod/direct 4/rm32/ESP 4/imm32 # add 4 to ESP -#? 51/push . . . . . . . . # push ECX -#? e8/call write_argv_3/disp32 -#? 81 0/subop/add 3/mod/direct 4/rm32/ESP 4/imm32 # add 4 to ESP eb/jump $argv_loop/disp8 $argv_break: # if (c2 == 0) return true @@ -82,61 +68,3 @@ $argv_break: $argv_fail: b8/copy . . . . . . . 0/imm32 # copy 0 to EAX c3/return - -write_stderr: # s : (address array byte) -> <void> - # save registers - 50/push . . . . . . . . # push EAX - 51/push . . . . . . . . # push ECX - 52/push . . . . . . . . # push EDX - 53/push . . . . . . . . # push EBX - # write(2/stderr, (data) s+4, (size) *s) - # fd = 2 (stderr) - bb/copy . . . . . . . 2/imm32 # copy 2 to EBX - # x = s+4 - 8b/copy 1/mod/*+disp8 4/rm32/SIB 4/base/ESP 4/index/none . 1/r32/ECX 0x14/disp8 . # copy *(ESP+20) to ECX - 81 0/subop/add 3/mod/direct 1/rm32/ECX . . . . . 4/imm32 # add 4 to ECX - # size = *s - 8b/copy 1/mod/*+disp8 4/rm32/SIB 4/base/ESP 4/index/none . 2/r32/EDX 0x14/disp8 . # copy *(ESP+20) to EDX - 8b/copy 0/mod/indirect 2/rm32/EDX . . . 2/r32/EDX . . # copy *EDX to EDX - # call write() - b8/copy . . . . . . . 4/imm32/write # copy 1 to EAX - cd/syscall 0x80/imm8 - # restore registers - 5b/pop . . . . . . . . # pop EBX - 5a/pop . . . . . . . . # pop EDX - 59/pop . . . . . . . . # pop ECX - 58/pop . . . . . . . . # pop EAX - # end - c3/return - -write_argv_3: # s : null-terminated ascii string of size exactly 3 -> <void> - # save registers - 50/push . . . . . . . . # push EAX - 51/push . . . . . . . . # push ECX - 52/push . . . . . . . . # push EDX - 53/push . . . . . . . . # push EBX - # write(2/stderr, (data) s+4, (size) *s) - # fd = 2 (stderr) - bb/copy . . . . . . . 2/imm32 # copy 2 to EBX - # x = s - 8b/copy 1/mod/*+disp8 4/rm32/SIB 4/base/ESP 4/index/none . 1/r32/ECX 0x14/disp8 . # copy *(ESP+20) to ECX - # size = 3 - ba/copy . . . . . . . 3/imm32 # copy 3 to EDX (hardcoded) - # call write() - b8/copy . . . . . . . 4/imm32/write # copy 1 to EAX - cd/syscall 0x80/imm8 - # restore registers - 5b/pop . . . . . . . . # pop EBX - 5a/pop . . . . . . . . # pop EDX - 59/pop . . . . . . . . # pop ECX - 58/pop . . . . . . . . # pop EAX - # end - c3/return - -== data -X: - 02 00 00 00 - 58/X 0a/newline -Y: - 02 00 00 00 - 59/Y 0a/newline |