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<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Mu - linux/apps/ex14.subx</title>
<meta name="Generator" content="Vim/8.2">
<meta name="plugin-version" content="vim8.1_v2">
<meta name="syntax" content="none">
<meta name="settings" content="number_lines,use_css,no_foldcolumn,expand_tabs,line_ids,prevent_copy=,use_input_for_pc=fallback">
<meta name="colorscheme" content="minimal-light">
<style>
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body { font-size:12pt; font-family: monospace; color: #000000; background-color: #ffffd7; }
a { color:inherit; }
* { font-size:12pt; font-size: 1em; }
.subxComment { color: #005faf; }
.subxS1Comment { color: #0000af; }
.subxS2Comment { color: #8a8a8a; }
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<body onload='JumpToLine();'>
<a href='https://github.com/akkartik/mu/blob/main/linux/apps/ex14.subx'>https://github.com/akkartik/mu/blob/main/linux/apps/ex14.subx</a>
<pre id='vimCodeElement'>
<span id="L1" class="LineNr"> 1 </span><span class="subxComment"># Multiply 2 numbers.</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">#   $ ./translate_subx 000init.subx apps/ex14.subx</span>
<span id="L5" class="LineNr"> 5 </span><span class="subxComment">#   $ ./a.elf</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 $?</span>
<span id="L8" class="LineNr"> 8 </span><span class="subxComment">#   6</span>
<span id="L9" class="LineNr"> 9 </span>
<span id="L10" class="LineNr">10 </span>== code
<span id="L11" class="LineNr">11 </span><span class="subxComment">#   instruction                     effective address                                                   register    displacement    immediate</span>
<span id="L12" class="LineNr">12 </span><span class="subxS1Comment"># . op          subop               mod             rm32          base        index         scale       r32</span>
<span id="L13" class="LineNr">13 </span><span class="subxS1Comment"># . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes</span>
<span id="L14" class="LineNr">14 </span>
<span id="L15" class="LineNr">15 </span><span class="SpecialChar">Entry</span>:
<span id="L16" class="LineNr">16 </span>    b8/copy-to-eax  1/imm32
<span id="L17" class="LineNr">17 </span>    b9/copy-to-ecx  2/imm32
<span id="L18" class="LineNr">18 </span>    bb/copy-to-ebx  3/imm32
<span id="L19" class="LineNr">19 </span>
<span id="L20" class="LineNr">20 </span>    69/multiply                     3/mod/direct    1/rm32/ecx   <span class="Normal"> . </span>         <span class="Normal"> . </span>           <span class="Normal"> . </span>          3/r32/ebx                   3/imm32           <span class="subxComment"># ebx = ecx * 3</span>
<span id="L21" class="LineNr">21 </span>
<span id="L22" class="LineNr">22 </span><span class="Constant">$exit</span>:
<span id="L23" class="LineNr">23 </span>    <span class="subxComment"># exit(ebx)</span>
<span id="L24" class="LineNr">24 </span>    e8/call  <a href='../000init.subx.html#L18'>syscall_exit</a>/disp32
<span id="L25" class="LineNr">25 </span>
<span id="L26" class="LineNr">26 </span><span class="subxS2Comment"># . . vim&#0058;nowrap:textwidth=0</span>
</pre>
</body>
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