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
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
|
<!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/factorial.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; }
.subxFunction { color: #af5f00; text-decoration: underline; }
.LineNr { }
.subxS1Comment { color: #0000af; }
.subxTest { color: #5f8700; }
.SpecialChar { color: #d70000; }
.Normal { color: #000000; background-color: #c6c6c6; padding-bottom: 1px; }
.Constant { color: #008787; }
.subxH1Comment { color: #005faf; text-decoration: underline; }
-->
</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/factorial.subx'>https://github.com/akkartik/mu/blob/master/apps/factorial.subx</a>
<pre id='vimCodeElement'>
<span id="L1" class="LineNr"> 1 </span><span class="subxComment">## compute the factorial of 5, and return the result in the exit code</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 0*.subx apps/factorial.subx -o apps/factorial</span>
<span id="L5" class="LineNr"> 5 </span><span class="subxComment"># $ ./subx run apps/factorial</span>
<span id="L6" class="LineNr"> 6 </span><span class="subxComment"># Expected result:</span>
<span id="L7" class="LineNr"> 7 </span><span class="subxComment"># $ echo $?</span>
<span id="L8" class="LineNr"> 8 </span><span class="subxComment"># 120</span>
<span id="L9" class="LineNr"> 9 </span><span class="subxComment">#</span>
<span id="L10" class="LineNr"> 10 </span><span class="subxComment"># You can also run the automated test suite:</span>
<span id="L11" class="LineNr"> 11 </span><span class="subxComment"># $ ./subx run apps/factorial test</span>
<span id="L12" class="LineNr"> 12 </span><span class="subxComment"># Expected output:</span>
<span id="L13" class="LineNr"> 13 </span><span class="subxComment"># ........</span>
<span id="L14" class="LineNr"> 14 </span><span class="subxComment"># Every '.' indicates a passing test. Failing tests get a 'F'.</span>
<span id="L15" class="LineNr"> 15 </span>
<span id="L16" class="LineNr"> 16 </span>== code
<span id="L17" class="LineNr"> 17 </span><span class="subxComment"># instruction effective address register displacement immediate</span>
<span id="L18" class="LineNr"> 18 </span><span class="subxS1Comment"># . op subop mod rm32 base index scale r32</span>
<span id="L19" class="LineNr"> 19 </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="L20" class="LineNr"> 20 </span>
<span id="L21" class="LineNr"> 21 </span><span class="SpecialChar">Entry</span>: <span class="subxComment"># run tests if necessary, compute `factorial(5)` if not</span>
<span id="L22" class="LineNr"> 22 </span> <span class="subxS1Comment"># . prologue</span>
<span id="L23" class="LineNr"> 23 </span> 89/copy 3/mod/direct 5/rm32/ebp <span class="Normal"> . </span> <span class="Normal"> . </span> <span class="Normal"> . </span> 4/r32/esp <span class="Normal"> . </span> <span class="Normal"> . </span> <span class="subxComment"># copy esp to ebp</span>
<span id="L24" class="LineNr"> 24 </span>
<span id="L25" class="LineNr"> 25 </span> <span class="subxComment"># initialize heap</span>
<span id="L26" class="LineNr"> 26 </span> <span class="subxS1Comment"># . Heap = new-segment(Heap-size)</span>
<span id="L27" class="LineNr"> 27 </span> <span class="subxS2Comment"># . . push args</span>
<span id="L28" class="LineNr"> 28 </span> 68/push <span class="SpecialChar"><a href='../069allocate.subx.html#L22'>Heap</a></span>/imm32
<span id="L29" class="LineNr"> 29 </span> 68/push <span class="SpecialChar"><a href='../069allocate.subx.html#L29'>Heap-size</a></span>/imm32
<span id="L30" class="LineNr"> 30 </span> <span class="subxS2Comment"># . . call</span>
<span id="L31" class="LineNr"> 31 </span> e8/call <a href='../053new-segment.subx.html#L41'>new-segment</a>/disp32
<span id="L32" class="LineNr"> 32 </span> <span class="subxS2Comment"># . . discard args</span>
<span id="L33" class="LineNr"> 33 </span> 81 0/subop/add 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> 8/imm32 <span class="subxComment"># add to esp</span>
<span id="L34" class="LineNr"> 34 </span>
<span id="L35" class="LineNr"> 35 </span> <span class="subxH1Comment"># - if argc > 1 and argv[1] == "test", then return run_tests()</span>
<span id="L36" class="LineNr"> 36 </span> <span class="subxComment"># if (argc <= 1) goto run-main</span>
<span id="L37" class="LineNr"> 37 </span> 81 7/subop/compare 1/mod/*+disp8 5/rm32/ebp <span class="Normal"> . </span> <span class="Normal"> . </span> <span class="Normal"> . </span> <span class="Normal"> . </span> 0/disp8 1/imm32 <span class="subxComment"># compare *ebp</span>
<span id="L38" class="LineNr"> 38 </span> 7e/jump-if-lesser-or-equal $run-main/disp8
<span id="L39" class="LineNr"> 39 </span> <span class="subxComment"># if (!kernel-string-equal?(argv[1], "test")) goto run-main</span>
<span id="L40" class="LineNr"> 40 </span> <span class="subxS1Comment"># . eax = kernel-string-equal?(argv[1], "test")</span>
<span id="L41" class="LineNr"> 41 </span> <span class="subxS2Comment"># . . push args</span>
<span id="L42" class="LineNr"> 42 </span> 68/push <span class="Constant">"test"</span>/imm32
<span id="L43" class="LineNr"> 43 </span> ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp <span class="Normal"> . </span> <span class="Normal"> . </span> <span class="Normal"> . </span> <span class="Normal"> . </span> 8/disp8 <span class="Normal"> . </span> <span class="subxComment"># push *(ebp+8)</span>
<span id="L44" class="LineNr"> 44 </span> <span class="subxS2Comment"># . . call</span>
<span id="L45" class="LineNr"> 45 </span> e8/call <a href='../052kernel-string-equal.subx.html#L31'>kernel-string-equal?</a>/disp32
<span id="L46" class="LineNr"> 46 </span> <span class="subxS2Comment"># . . discard args</span>
<span id="L47" class="LineNr"> 47 </span> 81 0/subop/add 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> 8/imm32 <span class="subxComment"># add to esp</span>
<span id="L48" class="LineNr"> 48 </span> <span class="subxS1Comment"># . if (eax == 0) goto run-main</span>
<span id="L49" class="LineNr"> 49 </span> 3d/compare-eax-and 0/imm32
<span id="L50" class="LineNr"> 50 </span> 74/jump-if-equal $run-main/disp8
<span id="L51" class="LineNr"> 51 </span> <span class="subxComment"># run-tests()</span>
<span id="L52" class="LineNr"> 52 </span> e8/call run-tests/disp32
<span id="L53" class="LineNr"> 53 </span> <span class="subxComment"># syscall(exit, *Num-test-failures)</span>
<span id="L54" class="LineNr"> 54 </span> 8b/copy 0/mod/indirect 5/rm32/.disp32 <span class="Normal"> . </span> <span class="Normal"> . </span> 3/r32/ebx <span class="SpecialChar"><a href='../051test.subx.html#L90'>Num-test-failures</a></span>/disp32 <span class="subxComment"># copy *Num-test-failures to ebx</span>
<span id="L55" class="LineNr"> 55 </span> eb/jump $main:end/disp8
<span id="L56" class="LineNr"> 56 </span><span class="Constant">$run-main</span>:
<span id="L57" class="LineNr"> 57 </span> <span class="subxH1Comment"># - otherwise return factorial(5)</span>
<span id="L58" class="LineNr"> 58 </span> <span class="subxComment"># eax = factorial(5)</span>
<span id="L59" class="LineNr"> 59 </span> <span class="subxS2Comment"># . . push args</span>
<span id="L60" class="LineNr"> 60 </span> 68/push 5/imm32
<span id="L61" class="LineNr"> 61 </span> <span class="subxS2Comment"># . . call</span>
<span id="L62" class="LineNr"> 62 </span> e8/call <a href='factorial.subx.html#L71'>factorial</a>/disp32
<span id="L63" class="LineNr"> 63 </span> <span class="subxS2Comment"># . . discard args</span>
<span id="L64" class="LineNr"> 64 </span> 81 0/subop/add 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"># add to esp</span>
<span id="L65" class="LineNr"> 65 </span> <span class="subxComment"># syscall(exit, eax)</span>
<span id="L66" class="LineNr"> 66 </span> 89/copy 3/mod/direct 3/rm32/ebx <span class="Normal"> . </span> <span class="Normal"> . </span> <span class="Normal"> . </span> 0/r32/eax <span class="Normal"> . </span> <span class="Normal"> . </span> <span class="subxComment"># copy eax to ebx</span>
<span id="L67" class="LineNr"> 67 </span><span class="Constant">$main:end</span>:
<span id="L68" class="LineNr"> 68 </span> b8/copy-to-eax 1/imm32/exit
<span id="L69" class="LineNr"> 69 </span> cd/syscall 0x80/imm8
<span id="L70" class="LineNr"> 70 </span>
<span id="L71" class="LineNr"> 71 </span><span class="subxFunction">factorial</span>: <span class="subxComment"># n : int -> int/eax</span>
<span id="L72" class="LineNr"> 72 </span> <span class="subxS1Comment"># . prologue</span>
<span id="L73" class="LineNr"> 73 </span> 55/push-ebp
<span id="L74" class="LineNr"> 74 </span> 89/copy 3/mod/direct 5/rm32/ebp <span class="Normal"> . </span> <span class="Normal"> . </span> <span class="Normal"> . </span> 4/r32/esp <span class="Normal"> . </span> <span class="Normal"> . </span> <span class="subxComment"># copy esp to ebp</span>
<span id="L75" class="LineNr"> 75 </span> 53/push-ebx
<span id="L76" class="LineNr"> 76 </span> <span class="subxComment"># if (n <= 1) return 1</span>
<span id="L77" class="LineNr"> 77 </span> b8/copy-to-eax 1/imm32
<span id="L78" class="LineNr"> 78 </span> 81 7/subop/compare 1/mod/*+disp8 5/rm32/ebp <span class="Normal"> . </span> <span class="Normal"> . </span> <span class="Normal"> . </span> <span class="Normal"> . </span> 8/disp8 1/imm32 <span class="subxComment"># compare *(ebp+8)</span>
<span id="L79" class="LineNr"> 79 </span> 7e/jump-if-<= $factorial:end/disp8
<span id="L80" class="LineNr"> 80 </span> <span class="subxComment"># ebx = n-1</span>
<span id="L81" class="LineNr"> 81 </span> 8b/copy 1/mod/*+disp8 5/rm32/ebp <span class="Normal"> . </span> <span class="Normal"> . </span> 3/r32/ebx 8/disp8 <span class="Normal"> . </span> <span class="subxComment"># copy *(ebp+8) to ebx</span>
<span id="L82" class="LineNr"> 82 </span> 4b/decrement-ebx
<span id="L83" class="LineNr"> 83 </span> <span class="subxComment"># eax = factorial(n-1)</span>
<span id="L84" class="LineNr"> 84 </span> <span class="subxS2Comment"># . . push args</span>
<span id="L85" class="LineNr"> 85 </span> 53/push-ebx
<span id="L86" class="LineNr"> 86 </span> <span class="subxS2Comment"># . . call</span>
<span id="L87" class="LineNr"> 87 </span> e8/call <a href='factorial.subx.html#L71'>factorial</a>/disp32
<span id="L88" class="LineNr"> 88 </span> <span class="subxS2Comment"># . . discard args</span>
<span id="L89" class="LineNr"> 89 </span> 81 0/subop/add 3/mod/direct 4/rm32/esp <span class="Normal"> . </span> <span class="Normal"> . </span> <span class="Normal"> . </span> <span class="Normal"> . </span> <span class="Normal"> . </span> 4/imm32 <span class="subxComment"># add to esp</span>
<span id="L90" class="LineNr"> 90 </span> <span class="subxComment"># return n * factorial(n-1)</span>
<span id="L91" class="LineNr"> 91 </span> f7 4/subop/multiply 1/mod/*+disp8 5/rm32/ebp <span class="Normal"> . </span> <span class="Normal"> . </span> 8/disp8 <span class="Normal"> . </span> <span class="subxComment"># multiply *(ebp+8) into eax</span>
<span id="L92" class="LineNr"> 92 </span> <span class="subxComment"># TODO: check for overflow</span>
<span id="L93" class="LineNr"> 93 </span><span class="Constant">$factorial:end</span>:
<span id="L94" class="LineNr"> 94 </span> <span class="subxS1Comment"># . epilogue</span>
<span id="L95" class="LineNr"> 95 </span> 5b/pop-to-ebx
<span id="L96" class="LineNr"> 96 </span> 89/copy 3/mod/direct 4/rm32/esp <span class="Normal"> . </span> <span class="Normal"> . </span> <span class="Normal"> . </span> 5/r32/ebp <span class="Normal"> . </span> <span class="Normal"> . </span> <span class="subxComment"># copy ebp to esp</span>
<span id="L97" class="LineNr"> 97 </span> 5d/pop-to-ebp
<span id="L98" class="LineNr"> 98 </span> c3/return
<span id="L99" class="LineNr"> 99 </span>
<span id="L100" class="LineNr">100 </span><span class="subxTest">test-factorial</span>:
<span id="L101" class="LineNr">101 </span> <span class="subxComment"># factorial(5)</span>
<span id="L102" class="LineNr">102 </span> <span class="subxS2Comment"># . . push args</span>
<span id="L103" class="LineNr">103 </span> 68/push 5/imm32
<span id="L104" class="LineNr">104 </span> <span class="subxS2Comment"># . . call</span>
<span id="L105" class="LineNr">105 </span> e8/call <a href='factorial.subx.html#L71'>factorial</a>/disp32
<span id="L106" class="LineNr">106 </span> <span class="subxS2Comment"># . . discard args</span>
<span id="L107" class="LineNr">107 </span> 81 0/subop/add 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"># add to esp</span>
<span id="L108" class="LineNr">108 </span> <span class="subxComment"># check-ints-equal(eax, 120, msg)</span>
<span id="L109" class="LineNr">109 </span> <span class="subxS2Comment"># . . push args</span>
<span id="L110" class="LineNr">110 </span> 68/push <span class="Constant">"F - test-factorial"</span>/imm32
<span id="L111" class="LineNr">111 </span> 68/push 0x78/imm32/expected-120
<span id="L112" class="LineNr">112 </span> 50/push-eax
<span id="L113" class="LineNr">113 </span> <span class="subxS2Comment"># . . call</span>
<span id="L114" class="LineNr">114 </span> e8/call <a href='../051test.subx.html#L24'>check-ints-equal</a>/disp32
<span id="L115" class="LineNr">115 </span> <span class="subxS2Comment"># . . discard args</span>
<span id="L116" class="LineNr">116 </span> 81 0/subop/add 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> 0xc/imm32 <span class="subxComment"># add to esp</span>
<span id="L117" class="LineNr">117 </span> <span class="subxComment"># end</span>
<span id="L118" class="LineNr">118 </span> c3/return
<span id="L119" class="LineNr">119 </span>
<span id="L120" class="LineNr">120 </span><span class="subxS2Comment"># . . vim:nowrap:textwidth=0</span>
</pre>
</body>
</html>
<!-- vim: set foldmethod=manual : -->
|