1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
|
<!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 - apps/ex5.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">
<!--
pre { font-family: monospace; color: #000000; background-color: #c6c6c6; }
body { font-size:12pt; font-family: monospace; color: #000000; background-color: #c6c6c6; }
a { color:inherit; }
* { font-size:12pt; font-size: 1em; }
.subxComment { color: #005faf; }
.subxS2Comment { color: #8a8a8a; }
.LineNr { }
.subxS1Comment { color: #0000af; }
.SpecialChar { color: #d70000; }
.Normal { color: #000000; background-color: #c6c6c6; padding-bottom: 1px; }
-->
</style>
<script type='text/javascript'>
<!--
/* function to open any folds containing a jumped-to line before jumping to it */
function JumpToLine()
{
var lineNum;
lineNum = window.location.hash;
lineNum = lineNum.substr(1); /* strip off '#' */
if (lineNum.indexOf('L') == -1) {
lineNum = 'L'+lineNum;
}
var lineElem = document.getElementById(lineNum);
/* Always jump to new location even if the line was hidden inside a fold, or
* we corrected the raw number to a line ID.
*/
if (lineElem) {
lineElem.scrollIntoView(true);
}
return true;
}
if ('onhashchange' in window) {
window.onhashchange = JumpToLine;
}
-->
</script>
</head>
<body onload='JumpToLine();'>
<a href='https://github.com/akkartik/mu/blob/master/apps/ex5.subx'>https://github.com/akkartik/mu/blob/master/apps/ex5.subx</a>
<pre id='vimCodeElement'>
<span id="L1" class="LineNr"> 1 </span><span class="subxComment"># Read a character from stdin, save it to a local on the stack, write it to stdout.</span>
<span id="L2" class="LineNr"> 2 </span><span class="subxComment">#</span>
<span id="L3" class="LineNr"> 3 </span><span class="subxComment"># To run:</span>
<span id="L4" class="LineNr"> 4 </span><span class="subxComment"># $ ./subx translate init.linux examples/ex5.subx -o examples/ex5</span>
<span id="L5" class="LineNr"> 5 </span><span class="subxComment"># $ ./subx run examples/ex5</span>
<span id="L6" class="LineNr"> 6 </span>
<span id="L7" class="LineNr"> 7 </span>== code
<span id="L8" class="LineNr"> 8 </span><span class="subxComment"># instruction effective address register displacement immediate</span>
<span id="L9" class="LineNr"> 9 </span><span class="subxS1Comment"># . op subop mod rm32 base index scale r32</span>
<span id="L10" class="LineNr">10 </span><span class="subxS1Comment"># . 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</span>
<span id="L11" class="LineNr">11 </span>
<span id="L12" class="LineNr">12 </span><span class="SpecialChar">Entry</span>:
<span id="L13" class="LineNr">13 </span>
<span id="L14" class="LineNr">14 </span> <span class="subxComment"># allocate x on the stack</span>
<span id="L15" class="LineNr">15 </span> 81 5/subop/subtract 3/mod/direct 4/rm32/esp <span class="Normal"> . </span> <span class="Normal"> . </span> <span class="Normal"> . </span> <span class="Normal"> . </span> <span class="Normal"> . </span> 4/imm32 <span class="subxComment"># subtract from esp</span>
<span id="L16" class="LineNr">16 </span>
<span id="L17" class="LineNr">17 </span> <span class="subxComment"># read(stdin, x, 1)</span>
<span id="L18" class="LineNr">18 </span> <span class="subxS1Comment"># . fd = 0 (stdin)</span>
<span id="L19" class="LineNr">19 </span> bb/copy-to-ebx 0/imm32
<span id="L20" class="LineNr">20 </span> <span class="subxS1Comment"># . data = x (location to write result to)</span>
<span id="L21" class="LineNr">21 </span> 8d/copy-address 1/mod/*+disp8 4/rm32/sib 4/base/esp 4/index/none 1/r32/ecx 4/disp8 <span class="Normal"> . </span> <span class="subxComment"># copy esp+4 to ecx</span>
<span id="L22" class="LineNr">22 </span> <span class="subxS1Comment"># . size = 1 character</span>
<span id="L23" class="LineNr">23 </span> ba/copy-to-edx 1/imm32
<span id="L24" class="LineNr">24 </span> <span class="subxS1Comment"># . syscall</span>
<span id="L25" class="LineNr">25 </span> e8/call syscall_read/disp32
<span id="L26" class="LineNr">26 </span>
<span id="L27" class="LineNr">27 </span> <span class="subxComment"># syscall(write, stdout, x, 1)</span>
<span id="L28" class="LineNr">28 </span> <span class="subxS1Comment"># . fd = 1 (stdout)</span>
<span id="L29" class="LineNr">29 </span> bb/copy-to-ebx 1/imm32
<span id="L30" class="LineNr">30 </span> <span class="subxS1Comment"># . data = x (location to read from)</span>
<span id="L31" class="LineNr">31 </span> 8d/copy-address 1/mod/*+disp8 4/rm32/sib 4/base/esp 4/index/none 1/r32/ecx 4/disp8 <span class="Normal"> . </span> <span class="subxComment"># copy esp+4 to ecx</span>
<span id="L32" class="LineNr">32 </span> <span class="subxS1Comment"># . size = 1 character</span>
<span id="L33" class="LineNr">33 </span> ba/copy-to-edx 1/imm32
<span id="L34" class="LineNr">34 </span> <span class="subxS1Comment"># . syscall</span>
<span id="L35" class="LineNr">35 </span> b8/copy-to-eax 4/imm32/write
<span id="L36" class="LineNr">36 </span> cd/syscall 0x80/imm8
<span id="L37" class="LineNr">37 </span>
<span id="L38" class="LineNr">38 </span> <span class="subxComment"># exit(ebx)</span>
<span id="L39" class="LineNr">39 </span> e8/call syscall_exit/disp32
<span id="L40" class="LineNr">40 </span>
<span id="L41" class="LineNr">41 </span><span class="subxS2Comment"># . . vim:nowrap:textwidth=0</span>
</pre>
</body>
</html>
<!-- vim: set foldmethod=manual : -->
|