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<a href='https://github.com/akkartik/mu/blob/main/linux/310copy-bytes.subx'>https://github.com/akkartik/mu/blob/main/linux/310copy-bytes.subx</a>
<pre id='vimCodeElement'>
<span id="L1" class="LineNr">  1 </span><span class="subxComment"># Some helpers for copying non-overlapping regions of memory.</span>
<span id="L2" class="LineNr">  2 </span><span class="subxComment"># Really only intended to be called from code generated by mu.subx.</span>
<span id="L3" class="LineNr">  3 </span>
<span id="L4" class="LineNr">  4 </span>== code
<span id="L5" class="LineNr">  5 </span>
<span id="L6" class="LineNr">  6 </span><span class="subxFunction">copy-bytes</span>:  <span class="subxComment"># src: (addr byte), dest: (addr byte), size: int</span>
<span id="L7" class="LineNr">  7 </span>    <span class="subxComment"># pseudocode:</span>
<span id="L8" class="LineNr">  8 </span>    <span class="subxComment">#   curr-src/esi = src</span>
<span id="L9" class="LineNr">  9 </span>    <span class="subxComment">#   curr-dest/edi = dest</span>
<span id="L10" class="LineNr"> 10 </span>    <span class="subxComment">#   i/ecx = 0</span>
<span id="L11" class="LineNr"> 11 </span>    <span class="subxComment">#   while true</span>
<span id="L12" class="LineNr"> 12 </span>    <span class="subxComment">#     if (i &gt;= size) break</span>
<span id="L13" class="LineNr"> 13 </span>    <span class="subxComment">#     *curr-dest = *curr-src</span>
<span id="L14" class="LineNr"> 14 </span>    <span class="subxComment">#     ++curr-src</span>
<span id="L15" class="LineNr"> 15 </span>    <span class="subxComment">#     ++curr-dest</span>
<span id="L16" class="LineNr"> 16 </span>    <span class="subxComment">#     ++i</span>
<span id="L17" class="LineNr"> 17 </span>    <span class="subxComment">#</span>
<span id="L18" class="LineNr"> 18 </span>    <span class="subxS1Comment"># . prologue</span>
<span id="L19" class="LineNr"> 19 </span>    55/push-ebp
<span id="L20" class="LineNr"> 20 </span>    89/&lt;- %ebp 4/r32/esp
<span id="L21" class="LineNr"> 21 </span>    <span class="subxS1Comment"># . save registers</span>
<span id="L22" class="LineNr"> 22 </span>    50/push-eax
<span id="L23" class="LineNr"> 23 </span>    51/push-ecx
<span id="L24" class="LineNr"> 24 </span>    52/push-edx
<span id="L25" class="LineNr"> 25 </span>    56/push-esi
<span id="L26" class="LineNr"> 26 </span>    57/push-edi
<span id="L27" class="LineNr"> 27 </span>    <span class="subxComment"># curr-src/esi = src</span>
<span id="L28" class="LineNr"> 28 </span>    8b/-&gt; *(ebp+8) 6/r32/esi
<span id="L29" class="LineNr"> 29 </span>    <span class="subxComment"># curr-dest/edi = dest</span>
<span id="L30" class="LineNr"> 30 </span>    8b/-&gt; *(ebp+0xc) 7/r32/edi
<span id="L31" class="LineNr"> 31 </span>    <span class="subxComment"># var i/ecx: int = 0</span>
<span id="L32" class="LineNr"> 32 </span>    b9/copy-to-ecx 0/imm32
<span id="L33" class="LineNr"> 33 </span>    <span class="subxComment"># edx = size</span>
<span id="L34" class="LineNr"> 34 </span>    8b/-&gt; *(ebp+0x10) 2/r32/edx
<span id="L35" class="LineNr"> 35 </span>    {
<span id="L36" class="LineNr"> 36 </span>      <span class="subxComment"># if (i &gt;= size) break</span>
<span id="L37" class="LineNr"> 37 </span>      39/compare %ecx 2/r32/edx
<span id="L38" class="LineNr"> 38 </span>      7d/jump-if-&gt;=  <span class="Constant">break</span>/disp8
<span id="L39" class="LineNr"> 39 </span>      <span class="subxComment"># *curr-dest = *curr-src</span>
<span id="L40" class="LineNr"> 40 </span>      8a/byte-&gt; *esi 0/r32/AL
<span id="L41" class="LineNr"> 41 </span>      88/byte&lt;- *edi 0/r32/AL
<span id="L42" class="LineNr"> 42 </span>      <span class="subxComment"># update</span>
<span id="L43" class="LineNr"> 43 </span>      46/increment-esi
<span id="L44" class="LineNr"> 44 </span>      47/increment-edi
<span id="L45" class="LineNr"> 45 </span>      41/increment-ecx
<span id="L46" class="LineNr"> 46 </span>      eb/jump <span class="Constant">loop</span>/disp8
<span id="L47" class="LineNr"> 47 </span>    }
<span id="L48" class="LineNr"> 48 </span><span class="Constant">$copy-bytes:end</span>:
<span id="L49" class="LineNr"> 49 </span>    <span class="subxS1Comment"># . restore registers</span>
<span id="L50" class="LineNr"> 50 </span>    5f/pop-to-edi
<span id="L51" class="LineNr"> 51 </span>    5e/pop-to-esi
<span id="L52" class="LineNr"> 52 </span>    5a/pop-to-edx
<span id="L53" class="LineNr"> 53 </span>    59/pop-to-ecx
<span id="L54" class="LineNr"> 54 </span>    58/pop-to-eax
<span id="L55" class="LineNr"> 55 </span>    <span class="subxS1Comment"># . epilogue</span>
<span id="L56" class="LineNr"> 56 </span>    89/&lt;- %esp 5/r32/ebp
<span id="L57" class="LineNr"> 57 </span>    5d/pop-to-ebp
<span id="L58" class="LineNr"> 58 </span>    c3/return
<span id="L59" class="LineNr"> 59 </span>
<span id="L60" class="LineNr"> 60 </span><span class="subxFunction">stream-to-array</span>:  <span class="subxComment"># in: (addr stream _), out: (addr handle array _)</span>
<span id="L61" class="LineNr"> 61 </span>    <span class="subxS1Comment"># . prologue</span>
<span id="L62" class="LineNr"> 62 </span>    55/push-ebp
<span id="L63" class="LineNr"> 63 </span>    89/&lt;- %ebp 4/r32/esp
<span id="L64" class="LineNr"> 64 </span>    <span class="subxS1Comment"># . save registers</span>
<span id="L65" class="LineNr"> 65 </span>    50/push-eax
<span id="L66" class="LineNr"> 66 </span>    51/push-ecx
<span id="L67" class="LineNr"> 67 </span>    52/push-edx
<span id="L68" class="LineNr"> 68 </span>    56/push-esi
<span id="L69" class="LineNr"> 69 </span>    <span class="subxComment"># esi = s</span>
<span id="L70" class="LineNr"> 70 </span>    8b/-&gt; *(ebp+8) 6/r32/esi
<span id="L71" class="LineNr"> 71 </span>    <span class="subxComment"># var len/ecx: int = s-&gt;write - s-&gt;read</span>
<span id="L72" class="LineNr"> 72 </span>    8b/-&gt; *esi 1/r32/ecx
<span id="L73" class="LineNr"> 73 </span>    2b/subtract *(esi+4) 1/r32/ecx
<span id="L74" class="LineNr"> 74 </span>    <span class="subxComment"># allocate</span>
<span id="L75" class="LineNr"> 75 </span>    (<a href='120allocate.subx.html#L584'>allocate-array</a> <span class="SpecialChar"><a href='120allocate.subx.html#L27'>Heap</a></span> %ecx *(ebp+0xc))
<span id="L76" class="LineNr"> 76 </span>    <span class="subxComment"># var in/edx: (addr byte) = s-&gt;data + s-&gt;read</span>
<span id="L77" class="LineNr"> 77 </span>    8b/-&gt; *(esi+4) 2/r32/edx
<span id="L78" class="LineNr"> 78 </span>    8d/copy-address *(esi+edx+0xc) 2/r32/edx
<span id="L79" class="LineNr"> 79 </span>    <span class="subxComment"># var dest/eax: (addr byte) = data for out</span>
<span id="L80" class="LineNr"> 80 </span>    8b/-&gt; *(ebp+0xc) 0/r32/eax
<span id="L81" class="LineNr"> 81 </span>    (<a href='120allocate.subx.html#L258'>lookup</a> *eax *(eax+4))  <span class="subxComment"># =&gt; eax</span>
<span id="L82" class="LineNr"> 82 </span>    8d/copy-address *(eax+4) 0/r32/eax
<span id="L83" class="LineNr"> 83 </span>    <span class="subxComment">#</span>
<span id="L84" class="LineNr"> 84 </span>    (<a href='310copy-bytes.subx.html#L6'>copy-bytes</a> %edx %eax %ecx)
<span id="L85" class="LineNr"> 85 </span><span class="Constant">$stream-to-array:end</span>:
<span id="L86" class="LineNr"> 86 </span>    <span class="subxS1Comment"># . restore registers</span>
<span id="L87" class="LineNr"> 87 </span>    5e/pop-to-esi
<span id="L88" class="LineNr"> 88 </span>    5a/pop-to-edx
<span id="L89" class="LineNr"> 89 </span>    59/pop-to-ecx
<span id="L90" class="LineNr"> 90 </span>    58/pop-to-eax
<span id="L91" class="LineNr"> 91 </span>    <span class="subxS1Comment"># . epilogue</span>
<span id="L92" class="LineNr"> 92 </span>    89/&lt;- %esp 5/r32/ebp
<span id="L93" class="LineNr"> 93 </span>    5d/pop-to-ebp
<span id="L94" class="LineNr"> 94 </span>    c3/return
<span id="L95" class="LineNr"> 95 </span>
<span id="L96" class="LineNr"> 96 </span><span class="subxTest">test-stream-to-array</span>:
<span id="L97" class="LineNr"> 97 </span>    <span class="subxS1Comment"># . prologue</span>
<span id="L98" class="LineNr"> 98 </span>    55/push-ebp
<span id="L99" class="LineNr"> 99 </span>    89/&lt;- %ebp 4/r32/esp
<span id="L100" class="LineNr">100 </span>    <span class="subxComment"># setup</span>
<span id="L101" class="LineNr">101 </span>    (<a href='106stream.subx.html#L17'>clear-stream</a> <a href='112read-byte.subx.html#L331'>_test-input-stream</a>)
<span id="L102" class="LineNr">102 </span>    (<a href='108write.subx.html#L24'>write</a> <a href='112read-byte.subx.html#L331'>_test-input-stream</a> <span class="Constant">&quot;abc&quot;</span>)
<span id="L103" class="LineNr">103 </span>    <span class="subxComment"># skip something</span>
<span id="L104" class="LineNr">104 </span>    (<a href='112read-byte.subx.html#L273'>read-byte</a> <a href='112read-byte.subx.html#L331'>_test-input-stream</a>)  <span class="subxComment"># =&gt; eax</span>
<span id="L105" class="LineNr">105 </span>    <span class="subxComment"># var out/ecx: (handle array byte)</span>
<span id="L106" class="LineNr">106 </span>    68/push 0/imm32
<span id="L107" class="LineNr">107 </span>    68/push 0/imm32
<span id="L108" class="LineNr">108 </span>    89/&lt;- %ecx 4/r32/esp
<span id="L109" class="LineNr">109 </span>    <span class="subxComment">#</span>
<span id="L110" class="LineNr">110 </span>    (<a href='310copy-bytes.subx.html#L60'>stream-to-array</a> <a href='112read-byte.subx.html#L331'>_test-input-stream</a> %ecx)
<span id="L111" class="LineNr">111 </span>    (<a href='120allocate.subx.html#L258'>lookup</a> *ecx *(ecx+4))  <span class="subxComment"># =&gt; eax</span>
<span id="L112" class="LineNr">112 </span>    (<a href='105string-equal.subx.html#L220'>check-strings-equal</a> %eax <span class="Constant">&quot;bc&quot;</span>)
<span id="L113" class="LineNr">113 </span>    <span class="subxS1Comment"># . epilogue</span>
<span id="L114" class="LineNr">114 </span>    89/&lt;- %esp 5/r32/ebp
<span id="L115" class="LineNr">115 </span>    5d/pop-to-ebp
<span id="L116" class="LineNr">116 </span>    c3/return
<span id="L117" class="LineNr">117 </span>
<span id="L118" class="LineNr">118 </span><span class="subxComment"># like stream-to-array but ignore surrounding quotes</span>
<span id="L119" class="LineNr">119 </span><span class="subxComment"># we might do other stuff here later</span>
<span id="L120" class="LineNr">120 </span><span class="subxFunction">unquote-stream-to-array</span>:  <span class="subxComment"># in: (addr stream _), out: (addr handle array _)</span>
<span id="L121" class="LineNr">121 </span>    <span class="subxS1Comment"># . prologue</span>
<span id="L122" class="LineNr">122 </span>    55/push-ebp
<span id="L123" class="LineNr">123 </span>    89/&lt;- %ebp 4/r32/esp
<span id="L124" class="LineNr">124 </span>    <span class="subxS1Comment"># . save registers</span>
<span id="L125" class="LineNr">125 </span>    50/push-eax
<span id="L126" class="LineNr">126 </span>    51/push-ecx
<span id="L127" class="LineNr">127 </span>    52/push-edx
<span id="L128" class="LineNr">128 </span>    56/push-esi
<span id="L129" class="LineNr">129 </span>    <span class="subxComment"># esi = s</span>
<span id="L130" class="LineNr">130 </span>    8b/-&gt; *(ebp+8) 6/r32/esi
<span id="L131" class="LineNr">131 </span>    <span class="subxComment"># var len/ecx: int = s-&gt;write - s-&gt;read - 2</span>
<span id="L132" class="LineNr">132 </span>    8b/-&gt; *esi 1/r32/ecx
<span id="L133" class="LineNr">133 </span>    2b/subtract *(esi+4) 1/r32/ecx
<span id="L134" class="LineNr">134 </span>    81 7/subop/compare %ecx 2/imm32
<span id="L135" class="LineNr">135 </span>    7c/jump-if-&lt; $unquote-stream-to-array:end/disp8
<span id="L136" class="LineNr">136 </span>    81 5/subop/subtract %ecx 2/imm32
<span id="L137" class="LineNr">137 </span>    <span class="subxComment"># allocate</span>
<span id="L138" class="LineNr">138 </span>    (<a href='120allocate.subx.html#L584'>allocate-array</a> <span class="SpecialChar"><a href='120allocate.subx.html#L27'>Heap</a></span> %ecx *(ebp+0xc))
<span id="L139" class="LineNr">139 </span>    <span class="subxComment"># var in/edx: (addr byte) = s-&gt;data + s-&gt;read + 1</span>
<span id="L140" class="LineNr">140 </span>    8b/-&gt; *(esi+4) 2/r32/edx
<span id="L141" class="LineNr">141 </span>    8d/copy-address *(esi+edx+0xd) 2/r32/edx  <span class="subxComment"># Stream-data + 1</span>
<span id="L142" class="LineNr">142 </span>    <span class="subxComment"># var dest/eax: (addr byte) = data for out</span>
<span id="L143" class="LineNr">143 </span>    8b/-&gt; *(ebp+0xc) 0/r32/eax
<span id="L144" class="LineNr">144 </span>    (<a href='120allocate.subx.html#L258'>lookup</a> *eax *(eax+4))  <span class="subxComment"># =&gt; eax</span>
<span id="L145" class="LineNr">145 </span>    8d/copy-address *(eax+4) 0/r32/eax
<span id="L146" class="LineNr">146 </span>    <span class="subxComment">#</span>
<span id="L147" class="LineNr">147 </span>    (<a href='310copy-bytes.subx.html#L6'>copy-bytes</a> %edx %eax %ecx)
<span id="L148" class="LineNr">148 </span><span class="Constant">$unquote-stream-to-array:end</span>:
<span id="L149" class="LineNr">149 </span>    <span class="subxS1Comment"># . restore registers</span>
<span id="L150" class="LineNr">150 </span>    5e/pop-to-esi
<span id="L151" class="LineNr">151 </span>    5a/pop-to-edx
<span id="L152" class="LineNr">152 </span>    59/pop-to-ecx
<span id="L153" class="LineNr">153 </span>    58/pop-to-eax
<span id="L154" class="LineNr">154 </span>    <span class="subxS1Comment"># . epilogue</span>
<span id="L155" class="LineNr">155 </span>    89/&lt;- %esp 5/r32/ebp
<span id="L156" class="LineNr">156 </span>    5d/pop-to-ebp
<span id="L157" class="LineNr">157 </span>    c3/return
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