mu - Soul of a tiny new machine. More thorough tests → More comprehensible and rewrite-friendly software → More resilient society.

	Commit message (Expand)	Author	Age	Files	Lines
*	6507 - use syscall names everywhere	Kartik Agaram	2020-06-10	1	-2/+1
*	6089	Kartik Agaram	2020-03-06	1	-2/+2
*	5856	Kartik Agaram	2020-01-01	1	-0/+41

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"> <html> <head> <meta http-equiv="content-type" content="text/html; charset=UTF-8"> <title>Mu - 091write-int.subx</title> <meta name="Generator" content="Vim/8.1"> <meta name="plugin-version" content="vim8.1_v1"> <meta name="syntax" content="none"> <meta name="settings" content="number_lines,use_css,no_foldcolumn,expand_tabs,line_ids,prevent_copy="> <meta name="colorscheme" content="minimal-light"> <style type="text/css">  </style> <script type='text/javascript'>  </script> </head> <body onload='JumpToLine();'> <a href='https://github.com/akkartik/mu/blob/master/091write-int.subx'>https://github.com/akkartik/mu/blob/master/091write-int.subx</a> <pre id='vimCodeElement'> 1 # write-int: add a single int to a stream 2 3 == code 4 # instruction effective address register displacement immediate 5 # . op subop mod rm32 base index scale r32 6 # . 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 7 8 write-int: # out: (addr stream byte), n: int 9 # . prologue 10 55/push-ebp 11 89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp 12 # . save registers 13 50/push-eax 14 51/push-ecx 15 57/push-edi 16 # edi = out 17 8b/copy 1/mod/*+disp8 5/rm32/ebp . . . 7/r32/edi 8/disp8 . # copy *(ebp+8) to edi 18 # ecx = out->write 19 8b/copy 0/mod/indirect 7/rm32/edi . . . 1/r32/ecx . . # copy *edi to ecx 20 # if (out->write >= out->length) abort 21 3b/compare 1/mod/*+disp8 7/rm32/edi . . . 1/r32/ecx 8/disp8 . # compare ecx with *(edi+8) 22 7d/jump-if->= $write-int:abort/disp8 23 $write-int:to-stream: 24 # out->data[out->write] = n 25 8b/copy 1/mod/*+disp8 5/rm32/ebp . . . 0/r32/eax 0xc/disp8 . # copy *(ebp+12) to eax 26 89/copy 1/mod/*+disp8 4/rm32/sib 7/base/edi 1/index/ecx . 0/r32/eax 0xc/disp8 . # copy eax to *(edi+ecx+12) 27 # out->write += 4 28 81 0/subop/add 0/mod/indirect 7/rm32/edi . . . . . 4/imm32 # add to *edi 29 $write-int:end: 30 # . restore registers 31 5f/pop-to-edi 32 59/pop-to-ecx 33 58/pop-to-eax 34 # . epilogue 35 89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp 36 5d/pop-to-ebp 37 c3/return 38 39 $write-int:abort: 40 # . _write(2/stderr, error) 41 # . . push args 42 68/push "write-int: out of space\n"/imm32 43 68/push 2/imm32/stderr 44 # . . call 45 e8/call <a href='050_write.subx.html#L14'>_write</a>/disp32 46 # . . discard args 47 81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp 48 # . syscall(exit, 1) 49 bb/copy-to-ebx 1/imm32 50 b8/copy-to-eax 1/imm32/exit 51 cd/syscall 0x80/imm8 52 # never gets here 53 54 test-write-int-single: 55 # - check that write-int writes to first int of 'stream' 56 # setup 57 # . clear-stream(_test-stream) 58 # . . push args 59 68/push <a href='057write.subx.html#L148'>_test-stream</a>/imm32 60 # . . call 61 e8/call <a href='055stream.subx.html#L17'>clear-stream</a>/disp32 62 # . . discard args 63 81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp 64 # write-int(_test-stream, "abcd") 65 # . . push args 66 68/push 0x64636261/imm32 67 68/push <a href='057write.subx.html#L148'>_test-stream</a>/imm32 68 # . . call 69 e8/call <a href='091write-int.subx.html#L8'>write-int</a>/disp32 70 # . . discard args 71 81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp 72 # check-stream-equal(_test-stream, "abcd", msg) 73 # . . push args 74 68/push "F - test-write-int-single"/imm32 75 68/push "abcd"/imm32 76 68/push <a href='057write.subx.html#L148'>_test-stream</a>/imm32 77 # . . call 78 e8/call <a href='058stream-equal.subx.html#L194'>check-stream-equal</a>/disp32 79 # . . discard args 80 81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp 81 # . end 82 c3/return 83 84 test-write-byte-buffered-multiple: 85 # - check that write-int correctly appends multiple writes 86 # setup 87 # . clear-stream(_test-stream) 88 # . . push args 89 68/push <a href='057write.subx.html#L148'>_test-stream</a>/imm32 90 # . . call 91 e8/call <a href='055stream.subx.html#L17'>clear-stream</a>/disp32 92 # . . discard args 93 81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp 94 # write-int(_test-stream, "abcd") 95 # . . push args 96 68/push 0x64636261/imm32 97 68/push <a href='057write.subx.html#L148'>_test-stream</a>/imm32 98 # . . call 99 e8/call <a href='091write-int.subx.html#L8'>write-int</a>/disp32 100 # . . discard args 101 81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp 102 # write-int(_test-stream, "efgh") 103 # . . push args 104 68/push 0x68676665/imm32 105 68/push <a href='057write.subx.html#L148'>_test-stream</a>/imm32 106 # . . call 107 e8/call <a href='091write-int.subx.html#L8'>write-int</a>/disp32 108 # . . discard args 109 81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp 110 # check-stream-equal(_test-stream, "abcdefgh", msg) 111 # . . push args 112 68/push "F - test-write-byte-buffered-multiple"/imm32 113 68/push "abcdefgh"/imm32 114 68/push <a href='057write.subx.html#L148'>_test-stream</a>/imm32 115 # . . call 116 e8/call <a href='058stream-equal.subx.html#L194'>check-stream-equal</a>/disp32 117 # . . discard args 118 81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 0xc/imm32 # add to esp 119 # . end 120 c3/return 121 122 # . . vim:nowrap:textwidth=0 </pre> </body> </html>