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<a href='https://github.com/akkartik/mu/blob/main/linux/apps/ex3.subx'>https://github.com/akkartik/mu/blob/main/linux/apps/ex3.subx</a>
<pre id='vimCodeElement'>
<span id="L1" class="LineNr"> 1 </span><span class="subxComment"># Add the first 10 numbers, 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">#   $ bootstrap/bootstrap translate apps/ex3.subx -o ex3</span>
<span id="L5" class="LineNr"> 5 </span><span class="subxComment">#   $ bootstrap/bootstrap run ex3</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 $?</span>
<span id="L8" class="LineNr"> 8 </span><span class="subxComment">#   55</span>
<span id="L9" class="LineNr"> 9 </span>
<span id="L10" class="LineNr">10 </span>== code
<span id="L11" class="LineNr">11 </span><span class="subxComment">#   instruction                     effective address                                                   register    displacement    immediate</span>
<span id="L12" class="LineNr">12 </span><span class="subxS1Comment"># . op          subop               mod             rm32          base        index         scale       r32</span>
<span id="L13" class="LineNr">13 </span><span class="subxS1Comment"># . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes</span>
<span id="L14" class="LineNr">14 </span>
<span id="L15" class="LineNr">15 </span><span class="SpecialChar">Entry</span>:
<span id="L16" class="LineNr">16 </span>    <span class="subxComment"># result: ebx = 0</span>
<span id="L17" class="LineNr">17 </span>    bb/copy-to-ebx  0/imm32
<span id="L18" class="LineNr">18 </span>    <span class="subxComment"># counter: ecx = 1</span>
<span id="L19" class="LineNr">19 </span>    b9/copy-to-ecx  1/imm32
<span id="L20" class="LineNr">20 </span>
<span id="L21" class="LineNr">21 </span><span class="Constant">$loop</span>:
<span id="L22" class="LineNr">22 </span>    <span class="subxComment"># if (counter &gt; 10) break</span>
<span id="L23" class="LineNr">23 </span>    81          7/subop/compare     3/mod/direct    1/rm32/ecx   <span class="Normal"> . </span>         <span class="Normal"> . </span>           <span class="Normal"> . </span>         <span class="Normal"> . </span>         <span class="Normal"> . </span>              0xa/imm32         <span class="subxComment"># compare ecx</span>
<span id="L24" class="LineNr">24 </span>    7f/jump-if-&gt;  $exit/disp8
<span id="L25" class="LineNr">25 </span>    <span class="subxComment"># result += counter</span>
<span id="L26" class="LineNr">26 </span>    01/add                          3/mod/direct    3/rm32/ebx   <span class="Normal"> . </span>         <span class="Normal"> . </span>           <span class="Normal"> . </span>          1/r32/ecx  <span class="Normal"> . </span>             <span class="Normal"> . </span>                <span class="subxComment"># add ecx to ebx</span>
<span id="L27" class="LineNr">27 </span>    <span class="subxComment"># ++counter</span>
<span id="L28" class="LineNr">28 </span>    41/increment-ecx
<span id="L29" class="LineNr">29 </span>    <span class="subxComment"># loop</span>
<span id="L30" class="LineNr">30 </span>    eb/jump  $loop/disp8
<span id="L31" class="LineNr">31 </span>
<span id="L32" class="LineNr">32 </span><span class="Constant">$exit</span>:
<span id="L33" class="LineNr">33 </span>    <span class="subxComment"># exit(ebx)</span>
<span id="L34" class="LineNr">34 </span>    e8/call  <a href='../000init.subx.html#L18'>syscall_exit</a>/disp32
<span id="L35" class="LineNr">35 </span>
<span id="L36" class="LineNr">36 </span><span class="subxS2Comment"># . . vim&#0058;nowrap:textwidth=0</span>
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