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<a href='https://github.com/akkartik/mu/blob/master/subx/010---vm.cc'>https://github.com/akkartik/mu/blob/master/subx/010---vm.cc</a>
<pre id='vimCodeElement'>
<span id="L1" class="LineNr">  1 </span><span class="Comment">//: Core data structures for simulating the SubX VM (subset of an x86 processor)</span>
<span id="L2" class="LineNr">  2 </span><span class="Comment">//:</span>
<span id="L3" class="LineNr">  3 </span><span class="Comment">//: At the lowest level (&quot;level 1&quot;) of abstraction, SubX executes x86</span>
<span id="L4" class="LineNr">  4 </span><span class="Comment">//: instructions provided in the form of an array of bytes, loaded into memory</span>
<span id="L5" class="LineNr">  5 </span><span class="Comment">//: starting at a specific address.</span>
<span id="L6" class="LineNr">  6 </span>
<span id="L7" class="LineNr">  7 </span><span class="SalientComment">//:: registers</span>
<span id="L8" class="LineNr">  8 </span><span class="Comment">//: assume segment registers are hard-coded to 0</span>
<span id="L9" class="LineNr">  9 </span><span class="Comment">//: no floating-point, MMX, etc. yet</span>
<span id="L10" class="LineNr"> 10 </span>
<span id="L11" class="LineNr"> 11 </span><span class="Delimiter">:(before &quot;End Types&quot;)</span>
<span id="L12" class="LineNr"> 12 </span><span class="Normal">enum</span> <span class="Delimiter">{</span>
<span id="L13" class="LineNr"> 13 </span>  <a href='010---vm.cc.html#L13'>EAX</a><span class="Delimiter">,</span>
<span id="L14" class="LineNr"> 14 </span>  <a href='010---vm.cc.html#L14'>ECX</a><span class="Delimiter">,</span>
<span id="L15" class="LineNr"> 15 </span>  <a href='010---vm.cc.html#L15'>EDX</a><span class="Delimiter">,</span>
<span id="L16" class="LineNr"> 16 </span>  <a href='010---vm.cc.html#L16'>EBX</a><span class="Delimiter">,</span>
<span id="L17" class="LineNr"> 17 </span>  <a href='010---vm.cc.html#L17'>ESP</a><span class="Delimiter">,</span>
<span id="L18" class="LineNr"> 18 </span>  <a href='010---vm.cc.html#L18'>EBP</a><span class="Delimiter">,</span>
<span id="L19" class="LineNr"> 19 </span>  <a href='010---vm.cc.html#L19'>ESI</a><span class="Delimiter">,</span>
<span id="L20" class="LineNr"> 20 </span>  <a href='010---vm.cc.html#L20'>EDI</a><span class="Delimiter">,</span>
<span id="L21" class="LineNr"> 21 </span>  <a href='010---vm.cc.html#L21'>NUM_INT_REGISTERS</a><span class="Delimiter">,</span>
<span id="L22" class="LineNr"> 22 </span><span class="Delimiter">};</span>
<span id="L23" class="LineNr"> 23 </span><span class="Normal">union</span> <a href='010---vm.cc.html#L23'>reg</a> <span class="Delimiter">{</span>
<span id="L24" class="LineNr"> 24 </span>  <span class="Normal">int32_t</span> i<span class="Delimiter">;</span>
<span id="L25" class="LineNr"> 25 </span>  <span class="Normal">uint32_t</span> u<span class="Delimiter">;</span>
<span id="L26" class="LineNr"> 26 </span><span class="Delimiter">};</span>
<span id="L27" class="LineNr"> 27 </span><span class="Delimiter">:(before &quot;End Globals&quot;)</span>
<span id="L28" class="LineNr"> 28 </span><a href='010---vm.cc.html#L23'>reg</a> <span class="Special"><a href='010---vm.cc.html#L28'>Reg</a></span>[NUM_INT_REGISTERS] = <span class="Delimiter">{</span> <span class="Delimiter">{</span><span class="Constant">0</span><span class="Delimiter">}</span> <span class="Delimiter">};</span>
<span id="L29" class="LineNr"> 29 </span><span class="Normal">uint32_t</span> EIP = <span class="Constant">1</span><span class="Delimiter">;</span>  <span class="Comment">// preserve null pointer</span>
<span id="L30" class="LineNr"> 30 </span><span class="Delimiter">:(before &quot;End Reset&quot;)</span>
<span id="L31" class="LineNr"> 31 </span>bzero<span class="Delimiter">(</span><span class="Special"><a href='010---vm.cc.html#L28'>Reg</a></span><span class="Delimiter">,</span> <span class="Normal">sizeof</span><span class="Delimiter">(</span><span class="Special"><a href='010---vm.cc.html#L28'>Reg</a></span><span class="Delimiter">));</span>
<span id="L32" class="LineNr"> 32 </span>EIP = <span class="Constant">1</span><span class="Delimiter">;</span>  <span class="Comment">// preserve null pointer</span>
<span id="L33" class="LineNr"> 33 </span>
<span id="L34" class="LineNr"> 34 </span><span class="Delimiter">:(before &quot;End <a href='001help.cc.html#L53'>Help</a> Contents&quot;)</span>
<span id="L35" class="LineNr"> 35 </span>cerr &lt;&lt; <span class="Constant">&quot;  registers\n&quot;</span><span class="Delimiter">;</span>
<span id="L36" class="LineNr"> 36 </span><span class="Delimiter">:(before &quot;End <a href='001help.cc.html#L53'>Help</a> Texts&quot;)</span>
<span id="L37" class="LineNr"> 37 </span><a href='001help.cc.html#L262'>put_new</a><span class="Delimiter">(</span><span class="Special"><a href='001help.cc.html#L53'>Help</a></span><span class="Delimiter">,</span> <span class="Constant">&quot;registers&quot;</span><span class="Delimiter">,</span>
<span id="L38" class="LineNr"> 38 </span>  <span class="Constant">&quot;SubX currently supports eight 32-bit integer registers. From 0 to 7, they are:\n&quot;</span>
<span id="L39" class="LineNr"> 39 </span>  <span class="Constant">&quot;  <a href='010---vm.cc.html#L13'>EAX</a> <a href='010---vm.cc.html#L14'>ECX</a> <a href='010---vm.cc.html#L15'>EDX</a> <a href='010---vm.cc.html#L16'>EBX</a> <a href='010---vm.cc.html#L17'>ESP</a> <a href='010---vm.cc.html#L18'>EBP</a> <a href='010---vm.cc.html#L19'>ESI</a> EDI\n&quot;</span>
<span id="L40" class="LineNr"> 40 </span>  <span class="Constant">&quot;ESP contains the top of the stack.\n&quot;</span>
<span id="L41" class="LineNr"> 41 </span>  <span class="Constant">&quot;\n&quot;</span>
<span id="L42" class="LineNr"> 42 </span>  <span class="Constant">&quot;-- 8-bit registers\n&quot;</span>
<span id="L43" class="LineNr"> 43 </span>  <span class="Constant">&quot;Some instructions operate on eight *overlapping* 8-bit registers.\n&quot;</span>
<span id="L44" class="LineNr"> 44 </span>  <span class="Constant">&quot;From 0 to 7, they are:\n&quot;</span>
<span id="L45" class="LineNr"> 45 </span>  <span class="Constant">&quot;  AL CL DL BL AH CH DH BH\n&quot;</span>
<span id="L46" class="LineNr"> 46 </span>  <span class="Constant">&quot;The 8-bit registers overlap with the 32-bit ones. AL is the lowest signicant byte\n&quot;</span>
<span id="L47" class="LineNr"> 47 </span>  <span class="Constant">&quot;of <a href='010---vm.cc.html#L13'>EAX</a>, AH is the second lowest significant byte, and so on.\n&quot;</span>
<span id="L48" class="LineNr"> 48 </span>  <span class="Constant">&quot;\n&quot;</span>
<span id="L49" class="LineNr"> 49 </span>  <span class="Constant">&quot;For example, if <a href='010---vm.cc.html#L16'>EBX</a> contains 0x11223344, then BL contains 0x44, and BH contains 0x33.\n&quot;</span>
<span id="L50" class="LineNr"> 50 </span>  <span class="Constant">&quot;\n&quot;</span>
<span id="L51" class="LineNr"> 51 </span>  <span class="Constant">&quot;There is no way to access bytes within <a href='010---vm.cc.html#L17'>ESP</a>, <a href='010---vm.cc.html#L18'>EBP</a>, <a href='010---vm.cc.html#L19'>ESI</a> or EDI.\n&quot;</span>
<span id="L52" class="LineNr"> 52 </span>  <span class="Constant">&quot;\n&quot;</span>
<span id="L53" class="LineNr"> 53 </span>  <span class="Constant">&quot;For complete details consult the IA-32 software developer's manual, volume 2,\n&quot;</span>
<span id="L54" class="LineNr"> 54 </span>  <span class="Constant">&quot;table 2-2, \&quot;</span><span class="Constant">32</span>-bit addressing forms with the ModR/<span class="Special">M</span> byte\<span class="Constant">&quot;.\n&quot;</span>
<span id="L55" class="LineNr"> 55 </span>  <span class="Constant">&quot;It is included in this repository as 'modrm.pdf'.\n&quot;</span>
<span id="L56" class="LineNr"> 56 </span>  <span class="Constant">&quot;The register encodings are described in the top row of the table, but you'll need\n&quot;</span>
<span id="L57" class="LineNr"> 57 </span>  <span class="Constant">&quot;to spend some time with it.\n&quot;</span>
<span id="L58" class="LineNr"> 58 </span>  <span class="Constant">&quot;\n&quot;</span>
<span id="L59" class="LineNr"> 59 </span>  <span class="Constant">&quot;-- flag registers\n&quot;</span>
<span id="L60" class="LineNr"> 60 </span>  <span class="Constant">&quot;Various instructions (particularly 'compare') modify one or more of three 1-bit 'flag'\n&quot;</span>
<span id="L61" class="LineNr"> 61 </span>  <span class="Constant">&quot;registers, as a side-effect:\n&quot;</span>
<span id="L62" class="LineNr"> 62 </span>  <span class="Constant">&quot;- the sign flag (SF): usually set if an arithmetic result is negative, or\n&quot;</span>
<span id="L63" class="LineNr"> 63 </span>  <span class="Constant">&quot;  <a href='000organization.cc.html#L148'>reset</a> if not.\n&quot;</span>
<span id="L64" class="LineNr"> 64 </span>  <span class="Constant">&quot;- the zero flag (ZF): usually set if a result is zero, or <a href='000organization.cc.html#L148'>reset</a> if not.\n&quot;</span>
<span id="L65" class="LineNr"> 65 </span>  <span class="Constant">&quot;- the overflow flag (OF): usually set if an arithmetic result overflows.\n&quot;</span>
<span id="L66" class="LineNr"> 66 </span>  <span class="Constant">&quot;The flag bits are read by conditional jumps.\n&quot;</span>
<span id="L67" class="LineNr"> 67 </span>  <span class="Constant">&quot;\n&quot;</span>
<span id="L68" class="LineNr"> 68 </span>  <span class="Constant">&quot;For complete details on how different instructions update the flags, consult the IA-32\n&quot;</span>
<span id="L69" class="LineNr"> 69 </span>  <span class="Constant">&quot;manual (volume 2). There's various versions of it online, such as <a href="https://c9x.me/x86,">https://c9x.me/x86,</a>\n&quot;</span>
<span id="L70" class="LineNr"> 70 </span>  <span class="Constant">&quot;though of course you'll need to be careful to ignore instructions and flag registers\n&quot;</span>
<span id="L71" class="LineNr"> 71 </span>  <span class="Constant">&quot;that SubX doesn't support.\n&quot;</span>
<span id="L72" class="LineNr"> 72 </span>  <span class="Constant">&quot;\n&quot;</span>
<span id="L73" class="LineNr"> 73 </span>  <span class="Constant">&quot;It isn't simple, but if this is the processor you have running on your computer,\n&quot;</span>
<span id="L74" class="LineNr"> 74 </span>  <span class="Constant">&quot;might as well get good at it.\n&quot;</span>
<span id="L75" class="LineNr"> 75 </span><span class="Delimiter">);</span>
<span id="L76" class="LineNr"> 76 </span>
<span id="L77" class="LineNr"> 77 </span><span class="Delimiter">:(before &quot;End Globals&quot;)</span>
<span id="L78" class="LineNr"> 78 </span><span class="Comment">// the subset of x86 flag registers we care about</span>
<span id="L79" class="LineNr"> 79 </span><span class="Normal">bool</span> SF = <span class="Constant">false</span><span class="Delimiter">;</span>  <span class="Comment">// sign flag</span>
<span id="L80" class="LineNr"> 80 </span><span class="Normal">bool</span> <a href='010---vm.cc.html#L80'>ZF</a> = <span class="Constant">false</span><span class="Delimiter">;</span>  <span class="Comment">// zero flag</span>
<span id="L81" class="LineNr"> 81 </span><span class="Normal">bool</span> <a href='010---vm.cc.html#L81'>OF</a> = <span class="Constant">false</span><span class="Delimiter">;</span>  <span class="Comment">// overflow flag</span>
<span id="L82" class="LineNr"> 82 </span><span class="Delimiter">:(before &quot;End Reset&quot;)</span>
<span id="L83" class="LineNr"> 83 </span>SF = <a href='010---vm.cc.html#L80'>ZF</a> = <a href='010---vm.cc.html#L81'>OF</a> = <span class="Constant">false</span><span class="Delimiter">;</span>
<span id="L84" class="LineNr"> 84 </span>
<span id="L85" class="LineNr"> 85 </span><span class="Comment">//: how the flag registers are updated after each instruction</span>
<span id="L86" class="LineNr"> 86 </span>
<span id="L87" class="LineNr"> 87 </span><span class="Delimiter">:(before &quot;End Includes&quot;)</span>
<span id="L88" class="LineNr"> 88 </span><span class="Comment">// Combine 'arg1' and 'arg2' with arithmetic operation 'op' and store the</span>
<span id="L89" class="LineNr"> 89 </span><span class="Comment">// result in 'arg1', then update flags.</span>
<span id="L90" class="LineNr"> 90 </span><span class="Comment">// beware: no side-effects in args</span>
<span id="L91" class="LineNr"> 91 </span><span class="PreProc">#define BINARY_ARITHMETIC_OP(op</span><span class="Delimiter">,</span><span class="PreProc"> arg1</span><span class="Delimiter">,</span><span class="PreProc"> arg2) </span><span class="Delimiter">{</span><span class="PreProc"> \</span>
<span id="L92" class="LineNr"> 92 </span><span class="PreProc">  </span><span class="Comment">/*</span><span class="Comment"> arg1 and arg2 must be signed </span><span class="Comment">*/</span><span class="PreProc"> \</span>
<span id="L93" class="LineNr"> 93 </span><span class="PreProc">  </span><span class="Normal">int64_t</span><span class="PreProc"> tmp = arg1 op arg2</span><span class="Delimiter">;</span><span class="PreProc"> \</span>
<span id="L94" class="LineNr"> 94 </span><span class="PreProc">  arg1 = arg1 op arg2</span><span class="Delimiter">;</span><span class="PreProc"> \</span>
<span id="L95" class="LineNr"> 95 </span><span class="PreProc">  trace(</span><span class="Special">Callstack_depth</span><span class="PreProc">+</span><span class="Constant">1</span><span class="Delimiter">,</span><span class="PreProc"> </span><span class="Constant">&quot;run&quot;</span><span class="PreProc">) &lt;&lt; </span><span class="Constant">&quot;storing 0x&quot;</span><span class="PreProc"> &lt;&lt; <a href='010---vm.cc.html#L440'>HEXWORD</a> &lt;&lt; arg1 &lt;&lt; end()</span><span class="Delimiter">;</span><span class="PreProc"> \</span>
<span id="L96" class="LineNr"> 96 </span><span class="PreProc">  SF = (arg1 &lt; </span><span class="Constant">0</span><span class="PreProc">)</span><span class="Delimiter">;</span><span class="PreProc"> \</span>
<span id="L97" class="LineNr"> 97 </span><span class="PreProc">  <a href='010---vm.cc.html#L80'>ZF</a> = (arg1 == </span><span class="Constant">0</span><span class="PreProc">)</span><span class="Delimiter">;</span><span class="PreProc"> \</span>
<span id="L98" class="LineNr"> 98 </span><span class="PreProc">  <a href='010---vm.cc.html#L81'>OF</a> = (arg1 != tmp)</span><span class="Delimiter">;</span><span class="PreProc"> \</span>
<span id="L99" class="LineNr"> 99 </span><span class="Delimiter">}</span>
<span id="L100" class="LineNr">100 </span>
<span id="L101" class="LineNr">101 </span><span class="Comment">// Combine 'arg1' and 'arg2' with bitwise operation 'op' and store the result</span>
<span id="L102" class="LineNr">102 </span><span class="Comment">// in 'arg1', then update flags.</span>
<span id="L103" class="LineNr">103 </span><span class="PreProc">#define BINARY_BITWISE_OP(op</span><span class="Delimiter">,</span><span class="PreProc"> arg1</span><span class="Delimiter">,</span><span class="PreProc"> arg2) </span><span class="Delimiter">{</span><span class="PreProc"> \</span>
<span id="L104" class="LineNr">104 </span><span class="PreProc">  </span><span class="Comment">/*</span><span class="Comment"> arg1 and arg2 must be unsigned </span><span class="Comment">*/</span><span class="PreProc"> \</span>
<span id="L105" class="LineNr">105 </span><span class="PreProc">  arg1 = arg1 op arg2</span><span class="Delimiter">;</span><span class="PreProc"> \</span>
<span id="L106" class="LineNr">106 </span><span class="PreProc">  trace(</span><span class="Special">Callstack_depth</span><span class="PreProc">+</span><span class="Constant">1</span><span class="Delimiter">,</span><span class="PreProc"> </span><span class="Constant">&quot;run&quot;</span><span class="PreProc">) &lt;&lt; </span><span class="Constant">&quot;storing 0x&quot;</span><span class="PreProc"> &lt;&lt; <a href='010---vm.cc.html#L440'>HEXWORD</a> &lt;&lt; arg1 &lt;&lt; end()</span><span class="Delimiter">;</span><span class="PreProc"> \</span>
<span id="L107" class="LineNr">107 </span><span class="PreProc">  SF = (arg1 &gt;&gt; </span><span class="Constant">31</span><span class="PreProc">)</span><span class="Delimiter">;</span><span class="PreProc"> \</span>
<span id="L108" class="LineNr">108 </span><span class="PreProc">  <a href='010---vm.cc.html#L80'>ZF</a> = (arg1 == </span><span class="Constant">0</span><span class="PreProc">)</span><span class="Delimiter">;</span><span class="PreProc"> \</span>
<span id="L109" class="LineNr">109 </span><span class="PreProc">  <a href='010---vm.cc.html#L81'>OF</a> = </span><span class="Constant">false</span><span class="Delimiter">;</span><span class="PreProc"> \</span>
<span id="L110" class="LineNr">110 </span><span class="Delimiter">}</span>
<span id="L111" class="LineNr">111 </span>
<span id="L112" class="LineNr">112 </span><span class="SalientComment">//:: simulated RAM</span>
<span id="L113" class="LineNr">113 </span>
<span id="L114" class="LineNr">114 </span><span class="Delimiter">:(before &quot;End Types&quot;)</span>
<span id="L115" class="LineNr">115 </span><span class="Normal">const</span> <span class="Normal">uint32_t</span> <a href='010---vm.cc.html#L115'>SEGMENT_ALIGNMENT</a> = <span class="Constant">0x1000000</span><span class="Delimiter">;</span>  <span class="Comment">// 16MB</span>
<span id="L116" class="LineNr">116 </span><span class="Normal">inline</span> <span class="Normal">uint32_t</span> <a href='010---vm.cc.html#L116'>align_upwards</a><span class="Delimiter">(</span><span class="Normal">uint32_t</span> x<span class="Delimiter">,</span> <span class="Normal">uint32_t</span> align<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L117" class="LineNr">117 </span>  <span class="Identifier">return</span> <span class="Delimiter">(</span>x+align-<span class="Constant">1</span><span class="Delimiter">)</span> &amp; -<span class="Delimiter">(</span>align<span class="Delimiter">);</span>
<span id="L118" class="LineNr">118 </span><span class="Delimiter">}</span>
<span id="L119" class="LineNr">119 </span>
<span id="L120" class="LineNr">120 </span><span class="Comment">// Like in real-world Linux, we'll allocate RAM for our programs in disjoint</span>
<span id="L121" class="LineNr">121 </span><span class="Comment">// slabs called VMAs or Virtual Memory Areas.</span>
<span id="L122" class="LineNr">122 </span><span class="Normal">struct</span> vma <span class="Delimiter">{</span>
<span id="L123" class="LineNr">123 </span>  <span class="Normal">uint32_t</span> start<span class="Delimiter">;</span>  <span class="Comment">// inclusive</span>
<span id="L124" class="LineNr">124 </span>  <span class="Normal">uint32_t</span> end<span class="Delimiter">;</span>  <span class="Comment">// exclusive</span>
<span id="L125" class="LineNr">125 </span>  vector&lt;<span class="Normal">uint8_t</span>&gt; <a href='010---vm.cc.html#L125'>_data</a><span class="Delimiter">;</span>
<span id="L126" class="LineNr">126 </span>  vma<span class="Delimiter">(</span><span class="Normal">uint32_t</span> s<span class="Delimiter">,</span> <span class="Normal">uint32_t</span> e<span class="Delimiter">)</span> :start<span class="Delimiter">(</span>s<span class="Delimiter">),</span> end<span class="Delimiter">(</span>e<span class="Delimiter">)</span> <span class="Delimiter">{}</span>
<span id="L127" class="LineNr">127 </span>  vma<span class="Delimiter">(</span><span class="Normal">uint32_t</span> s<span class="Delimiter">)</span> :start<span class="Delimiter">(</span>s<span class="Delimiter">),</span> end<span class="Delimiter">(</span><a href='010---vm.cc.html#L116'>align_upwards</a><span class="Delimiter">(</span>s+<span class="Constant">1</span><span class="Delimiter">,</span> <a href='010---vm.cc.html#L115'>SEGMENT_ALIGNMENT</a><span class="Delimiter">))</span> <span class="Delimiter">{}</span>
<span id="L128" class="LineNr">128 </span>  <span class="Normal">bool</span> <a href='010---vm.cc.html#L128'>match</a><span class="Delimiter">(</span><span class="Normal">uint32_t</span> a<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L129" class="LineNr">129 </span>    <span class="Identifier">return</span> a &gt;= start &amp;&amp; a &lt; end<span class="Delimiter">;</span>
<span id="L130" class="LineNr">130 </span>  <span class="Delimiter">}</span>
<span id="L131" class="LineNr">131 </span>  <span class="Normal">bool</span> <a href='010---vm.cc.html#L131'>match32</a><span class="Delimiter">(</span><span class="Normal">uint32_t</span> a<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L132" class="LineNr">132 </span>    <span class="Identifier">return</span> a &gt;= start &amp;&amp; a+<span class="Constant">4</span> &lt;= end<span class="Delimiter">;</span>
<span id="L133" class="LineNr">133 </span>  <span class="Delimiter">}</span>
<span id="L134" class="LineNr">134 </span>  <span class="Normal">uint8_t</span>&amp; data<span class="Delimiter">(</span><span class="Normal">uint32_t</span> a<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L135" class="LineNr">135 </span>    assert<span class="Delimiter">(</span><a href='010---vm.cc.html#L128'>match</a><span class="Delimiter">(</span>a<span class="Delimiter">));</span>
<span id="L136" class="LineNr">136 </span>    <span class="Normal">uint32_t</span> result_index = a-start<span class="Delimiter">;</span>
<span id="L137" class="LineNr">137 </span>    <span class="Normal">if</span> <span class="Delimiter">(</span><a href='010---vm.cc.html#L125'>_data</a><span class="Delimiter">.</span>size<span class="Delimiter">()</span> &lt;= result_index<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L138" class="LineNr">138 </span>      <span class="Normal">const</span> <span class="Normal">int</span> align = <span class="Constant">0x1000</span><span class="Delimiter">;</span>
<span id="L139" class="LineNr">139 </span>      <span class="Normal">uint32_t</span> result_size = result_index + <span class="Constant">1</span><span class="Delimiter">;</span>  <span class="Comment">// size needed for result_index to be valid</span>
<span id="L140" class="LineNr">140 </span>      <span class="Normal">uint32_t</span> new_size = <a href='010---vm.cc.html#L116'>align_upwards</a><span class="Delimiter">(</span>result_size<span class="Delimiter">,</span> align<span class="Delimiter">);</span>
<span id="L141" class="LineNr">141 </span>      <span class="Comment">// grow at least 2x to maintain some amortized complexity guarantees</span>
<span id="L142" class="LineNr">142 </span>      <span class="Normal">if</span> <span class="Delimiter">(</span>new_size &lt; <a href='010---vm.cc.html#L125'>_data</a><span class="Delimiter">.</span>size<span class="Delimiter">()</span> * <span class="Constant">2</span><span class="Delimiter">)</span>
<span id="L143" class="LineNr">143 </span>        new_size = <a href='010---vm.cc.html#L125'>_data</a><span class="Delimiter">.</span>size<span class="Delimiter">()</span> * <span class="Constant">2</span><span class="Delimiter">;</span>
<span id="L144" class="LineNr">144 </span>      <span class="Comment">// never grow past the stated limit</span>
<span id="L145" class="LineNr">145 </span>      <span class="Normal">if</span> <span class="Delimiter">(</span>new_size &gt; end-start<span class="Delimiter">)</span>
<span id="L146" class="LineNr">146 </span>        new_size = end-start<span class="Delimiter">;</span>
<span id="L147" class="LineNr">147 </span>      <a href='010---vm.cc.html#L125'>_data</a><span class="Delimiter">.</span>resize<span class="Delimiter">(</span>new_size<span class="Delimiter">);</span>
<span id="L148" class="LineNr">148 </span>    <span class="Delimiter">}</span>
<span id="L149" class="LineNr">149 </span>    <span class="Identifier">return</span> <a href='010---vm.cc.html#L125'>_data</a><span class="Delimiter">.</span>at<span class="Delimiter">(</span>result_index<span class="Delimiter">);</span>
<span id="L150" class="LineNr">150 </span>  <span class="Delimiter">}</span>
<span id="L151" class="LineNr">151 </span>  <span class="Normal">void</span> <a href='010---vm.cc.html#L151'>grow_until</a><span class="Delimiter">(</span><span class="Normal">uint32_t</span> new_end_address<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L152" class="LineNr">152 </span>    <span class="Normal">if</span> <span class="Delimiter">(</span>new_end_address &lt; end<span class="Delimiter">)</span> <span class="Identifier">return</span><span class="Delimiter">;</span>
<span id="L153" class="LineNr">153 </span>    <span class="Comment">// Ugly: vma knows about the global Memory list of vmas</span>
<span id="L154" class="LineNr">154 </span>    <span class="Normal">void</span> <a href='010---vm.cc.html#L161'>sanity_check</a><span class="Delimiter">(</span><span class="Normal">uint32_t</span> start<span class="Delimiter">,</span> <span class="Normal">uint32_t</span> end<span class="Delimiter">);</span>
<span id="L155" class="LineNr">155 </span>    <a href='010---vm.cc.html#L161'>sanity_check</a><span class="Delimiter">(</span>start<span class="Delimiter">,</span> new_end_address<span class="Delimiter">);</span>
<span id="L156" class="LineNr">156 </span>    end = new_end_address<span class="Delimiter">;</span>
<span id="L157" class="LineNr">157 </span>  <span class="Delimiter">}</span>
<span id="L158" class="LineNr">158 </span>  <span class="Comment">// End vma Methods</span>
<span id="L159" class="LineNr">159 </span><span class="Delimiter">};</span>
<span id="L160" class="LineNr">160 </span><span class="Delimiter">:(code)</span>
<span id="L161" class="LineNr">161 </span><span class="Normal">void</span> <a href='010---vm.cc.html#L161'>sanity_check</a><span class="Delimiter">(</span><span class="Normal">uint32_t</span> start<span class="Delimiter">,</span> <span class="Normal">uint32_t</span> end<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L162" class="LineNr">162 </span>  <span class="Normal">bool</span> dup_found = <span class="Constant">false</span><span class="Delimiter">;</span>
<span id="L163" class="LineNr">163 </span>  <span class="Normal">for</span> <span class="Delimiter">(</span><span class="Normal">int</span> i = <span class="Constant">0</span><span class="Delimiter">;</span>  i &lt; <a href='001help.cc.html#L166'>SIZE</a><span class="Delimiter">(</span><span class="Special"><a href='010---vm.cc.html#L180'>Mem</a></span><span class="Delimiter">);</span>  ++i<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L164" class="LineNr">164 </span>    <span class="Normal">const</span> vma&amp; curr = <span class="Special"><a href='010---vm.cc.html#L180'>Mem</a></span><span class="Delimiter">.</span>at<span class="Delimiter">(</span>i<span class="Delimiter">);</span>
<span id="L165" class="LineNr">165 </span>    <span class="Normal">if</span> <span class="Delimiter">(</span>curr<span class="Delimiter">.</span>start == start<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L166" class="LineNr">166 </span>      assert<span class="Delimiter">(</span>!dup_found<span class="Delimiter">);</span>
<span id="L167" class="LineNr">167 </span>      dup_found = <span class="Constant">true</span><span class="Delimiter">;</span>
<span id="L168" class="LineNr">168 </span>    <span class="Delimiter">}</span>
<span id="L169" class="LineNr">169 </span>    <span class="Normal">else</span> <span class="Normal">if</span> <span class="Delimiter">(</span>curr<span class="Delimiter">.</span>start &gt; start<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L170" class="LineNr">170 </span>      assert<span class="Delimiter">(</span>curr<span class="Delimiter">.</span>start &gt; end<span class="Delimiter">);</span>
<span id="L171" class="LineNr">171 </span>    <span class="Delimiter">}</span>
<span id="L172" class="LineNr">172 </span>    <span class="Normal">else</span> <span class="Normal">if</span> <span class="Delimiter">(</span>curr<span class="Delimiter">.</span>start &lt; start<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L173" class="LineNr">173 </span>      assert<span class="Delimiter">(</span>curr<span class="Delimiter">.</span>end &lt; start<span class="Delimiter">);</span>
<span id="L174" class="LineNr">174 </span>    <span class="Delimiter">}</span>
<span id="L175" class="LineNr">175 </span>  <span class="Delimiter">}</span>
<span id="L176" class="LineNr">176 </span><span class="Delimiter">}</span>
<span id="L177" class="LineNr">177 </span>
<span id="L178" class="LineNr">178 </span><span class="Delimiter">:(before &quot;End Globals&quot;)</span>
<span id="L179" class="LineNr">179 </span><span class="Comment">// RAM is made of VMAs.</span>
<span id="L180" class="LineNr">180 </span>vector&lt;vma&gt; <span class="Special"><a href='010---vm.cc.html#L180'>Mem</a></span><span class="Delimiter">;</span>
<span id="L181" class="LineNr">181 </span><span class="Delimiter">:(code)</span>
<span id="L182" class="LineNr">182 </span><span class="Comment">// The first 3 VMAs are special. When loading ELF binaries in later layers,</span>
<span id="L183" class="LineNr">183 </span><span class="Comment">// we'll assume that the first VMA is for code, the second is for data</span>
<span id="L184" class="LineNr">184 </span><span class="Comment">// (including the heap), and the third for the stack.</span>
<span id="L185" class="LineNr">185 </span><span class="Normal">void</span> <a href='010---vm.cc.html#L185'>grow_code_segment</a><span class="Delimiter">(</span><span class="Normal">uint32_t</span> new_end_address<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L186" class="LineNr">186 </span>  assert<span class="Delimiter">(</span>!<span class="Special"><a href='010---vm.cc.html#L180'>Mem</a></span><span class="Delimiter">.</span>empty<span class="Delimiter">());</span>
<span id="L187" class="LineNr">187 </span>  <span class="Special"><a href='010---vm.cc.html#L180'>Mem</a></span><span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">).</span><a href='010---vm.cc.html#L151'>grow_until</a><span class="Delimiter">(</span>new_end_address<span class="Delimiter">);</span>
<span id="L188" class="LineNr">188 </span><span class="Delimiter">}</span>
<span id="L189" class="LineNr">189 </span><span class="Normal">void</span> <a href='010---vm.cc.html#L189'>grow_data_segment</a><span class="Delimiter">(</span><span class="Normal">uint32_t</span> new_end_address<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L190" class="LineNr">190 </span>  assert<span class="Delimiter">(</span><a href='001help.cc.html#L166'>SIZE</a><span class="Delimiter">(</span><span class="Special"><a href='010---vm.cc.html#L180'>Mem</a></span><span class="Delimiter">)</span> &gt; <span class="Constant">1</span><span class="Delimiter">);</span>
<span id="L191" class="LineNr">191 </span>  <span class="Special"><a href='010---vm.cc.html#L180'>Mem</a></span><span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">).</span><a href='010---vm.cc.html#L151'>grow_until</a><span class="Delimiter">(</span>new_end_address<span class="Delimiter">);</span>
<span id="L192" class="LineNr">192 </span><span class="Delimiter">}</span>
<span id="L193" class="LineNr">193 </span><span class="Delimiter">:(before &quot;End Globals&quot;)</span>
<span id="L194" class="LineNr">194 </span><span class="Normal">uint32_t</span> <span class="Special"><a href='010---vm.cc.html#L194'>End_of_program</a></span> = <span class="Constant">0</span><span class="Delimiter">;</span>  <span class="Comment">// when the program executes past this address in tests we'll stop the test</span>
<span id="L195" class="LineNr">195 </span><span class="Comment">// The stack grows downward. Can't increase its size for now.</span>
<span id="L196" class="LineNr">196 </span><span class="Delimiter">:(before &quot;End Reset&quot;)</span>
<span id="L197" class="LineNr">197 </span><span class="Special"><a href='010---vm.cc.html#L180'>Mem</a></span><span class="Delimiter">.</span>clear<span class="Delimiter">();</span>
<span id="L198" class="LineNr">198 </span><span class="Special"><a href='010---vm.cc.html#L194'>End_of_program</a></span> = <span class="Constant">0</span><span class="Delimiter">;</span>
<span id="L199" class="LineNr">199 </span><span class="Delimiter">:(code)</span>
<span id="L200" class="LineNr">200 </span><span class="Comment">// These helpers depend on Mem being laid out contiguously (so you can't use a</span>
<span id="L201" class="LineNr">201 </span><span class="Comment">// map, etc.) and on the host also being little-endian.</span>
<span id="L202" class="LineNr">202 </span><span class="Normal">inline</span> <span class="Normal">uint8_t</span> <a href='010---vm.cc.html#L202'>read_mem_u8</a><span class="Delimiter">(</span><span class="Normal">uint32_t</span> addr<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L203" class="LineNr">203 </span>  <span class="Normal">uint8_t</span>* handle = <a href='010---vm.cc.html#L217'>mem_addr_u8</a><span class="Delimiter">(</span>addr<span class="Delimiter">);</span>  <span class="Comment">// error messages get printed here</span>
<span id="L204" class="LineNr">204 </span>  <span class="Identifier">return</span> handle ? *handle : <span class="Constant">0</span><span class="Delimiter">;</span>
<span id="L205" class="LineNr">205 </span><span class="Delimiter">}</span>
<span id="L206" class="LineNr">206 </span><span class="Normal">inline</span> <span class="Normal">int8_t</span> <a href='010---vm.cc.html#L206'>read_mem_i8</a><span class="Delimiter">(</span><span class="Normal">uint32_t</span> addr<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L207" class="LineNr">207 </span>  <span class="Identifier">return</span> <span class="Normal">static_cast</span>&lt;<span class="Normal">int8_t</span>&gt;<span class="Delimiter">(</span><a href='010---vm.cc.html#L202'>read_mem_u8</a><span class="Delimiter">(</span>addr<span class="Delimiter">));</span>
<span id="L208" class="LineNr">208 </span><span class="Delimiter">}</span>
<span id="L209" class="LineNr">209 </span><span class="Normal">inline</span> <span class="Normal">uint32_t</span> <a href='010---vm.cc.html#L209'>read_mem_u32</a><span class="Delimiter">(</span><span class="Normal">uint32_t</span> addr<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L210" class="LineNr">210 </span>  <span class="Normal">uint32_t</span>* handle = <a href='010---vm.cc.html#L233'>mem_addr_u32</a><span class="Delimiter">(</span>addr<span class="Delimiter">);</span>  <span class="Comment">// error messages get printed here</span>
<span id="L211" class="LineNr">211 </span>  <span class="Identifier">return</span> handle ? *handle : <span class="Constant">0</span><span class="Delimiter">;</span>
<span id="L212" class="LineNr">212 </span><span class="Delimiter">}</span>
<span id="L213" class="LineNr">213 </span><span class="Normal">inline</span> <span class="Normal">int32_t</span> <a href='010---vm.cc.html#L213'>read_mem_i32</a><span class="Delimiter">(</span><span class="Normal">uint32_t</span> addr<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L214" class="LineNr">214 </span>  <span class="Identifier">return</span> <span class="Normal">static_cast</span>&lt;<span class="Normal">int32_t</span>&gt;<span class="Delimiter">(</span><a href='010---vm.cc.html#L209'>read_mem_u32</a><span class="Delimiter">(</span>addr<span class="Delimiter">));</span>
<span id="L215" class="LineNr">215 </span><span class="Delimiter">}</span>
<span id="L216" class="LineNr">216 </span>
<span id="L217" class="LineNr">217 </span><span class="Normal">inline</span> <span class="Normal">uint8_t</span>* <a href='010---vm.cc.html#L217'>mem_addr_u8</a><span class="Delimiter">(</span><span class="Normal">uint32_t</span> addr<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L218" class="LineNr">218 </span>  <span class="Normal">uint8_t</span>* result = <span class="Constant">NULL</span><span class="Delimiter">;</span>
<span id="L219" class="LineNr">219 </span>  <span class="Normal">for</span> <span class="Delimiter">(</span><span class="Normal">int</span> i = <span class="Constant">0</span><span class="Delimiter">;</span>  i &lt; <a href='001help.cc.html#L166'>SIZE</a><span class="Delimiter">(</span><span class="Special"><a href='010---vm.cc.html#L180'>Mem</a></span><span class="Delimiter">);</span>  ++i<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L220" class="LineNr">220 </span>    <span class="Normal">if</span> <span class="Delimiter">(</span><span class="Special"><a href='010---vm.cc.html#L180'>Mem</a></span><span class="Delimiter">.</span>at<span class="Delimiter">(</span>i<span class="Delimiter">).</span><a href='010---vm.cc.html#L128'>match</a><span class="Delimiter">(</span>addr<span class="Delimiter">))</span> <span class="Delimiter">{</span>
<span id="L221" class="LineNr">221 </span>      <span class="Normal">if</span> <span class="Delimiter">(</span>result<span class="Delimiter">)</span>
<span id="L222" class="LineNr">222 </span>        <a href='003trace.cc.html#L202'>raise</a> &lt;&lt; <span class="Constant">&quot;address 0x&quot;</span> &lt;&lt; <a href='010---vm.cc.html#L440'>HEXWORD</a> &lt;&lt; addr &lt;&lt; <span class="Constant">&quot; is in two segments\n&quot;</span> &lt;&lt; end<span class="Delimiter">();</span>
<span id="L223" class="LineNr">223 </span>      result = &amp;<span class="Special"><a href='010---vm.cc.html#L180'>Mem</a></span><span class="Delimiter">.</span>at<span class="Delimiter">(</span>i<span class="Delimiter">).</span>data<span class="Delimiter">(</span>addr<span class="Delimiter">);</span>
<span id="L224" class="LineNr">224 </span>    <span class="Delimiter">}</span>
<span id="L225" class="LineNr">225 </span>  <span class="Delimiter">}</span>
<span id="L226" class="LineNr">226 </span>  <span class="Normal">if</span> <span class="Delimiter">(</span>result == <span class="Constant">NULL</span><span class="Delimiter">)</span>
<span id="L227" class="LineNr">227 </span>    <a href='003trace.cc.html#L202'>raise</a> &lt;&lt; <span class="Constant">&quot;Tried to access uninitialized memory at address 0x&quot;</span> &lt;&lt; <a href='010---vm.cc.html#L440'>HEXWORD</a> &lt;&lt; addr &lt;&lt; <span class="cSpecial">'\n'</span> &lt;&lt; end<span class="Delimiter">();</span>
<span id="L228" class="LineNr">228 </span>  <span class="Identifier">return</span> result<span class="Delimiter">;</span>
<span id="L229" class="LineNr">229 </span><span class="Delimiter">}</span>
<span id="L230" class="LineNr">230 </span><span class="Normal">inline</span> <span class="Normal">int8_t</span>* <a href='010---vm.cc.html#L230'>mem_addr_i8</a><span class="Delimiter">(</span><span class="Normal">uint32_t</span> addr<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L231" class="LineNr">231 </span>  <span class="Identifier">return</span> <span class="Normal">reinterpret_cast</span>&lt;<span class="Normal">int8_t</span>*&gt;<span class="Delimiter">(</span><a href='010---vm.cc.html#L217'>mem_addr_u8</a><span class="Delimiter">(</span>addr<span class="Delimiter">));</span>
<span id="L232" class="LineNr">232 </span><span class="Delimiter">}</span>
<span id="L233" class="LineNr">233 </span><span class="Normal">inline</span> <span class="Normal">uint32_t</span>* <a href='010---vm.cc.html#L233'>mem_addr_u32</a><span class="Delimiter">(</span><span class="Normal">uint32_t</span> addr<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L234" class="LineNr">234 </span>  <span class="Normal">uint32_t</span>* result = <span class="Constant">NULL</span><span class="Delimiter">;</span>
<span id="L235" class="LineNr">235 </span>  <span class="Normal">for</span> <span class="Delimiter">(</span><span class="Normal">int</span> i = <span class="Constant">0</span><span class="Delimiter">;</span>  i &lt; <a href='001help.cc.html#L166'>SIZE</a><span class="Delimiter">(</span><span class="Special"><a href='010---vm.cc.html#L180'>Mem</a></span><span class="Delimiter">);</span>  ++i<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L236" class="LineNr">236 </span>    <span class="Normal">if</span> <span class="Delimiter">(</span><span class="Special"><a href='010---vm.cc.html#L180'>Mem</a></span><span class="Delimiter">.</span>at<span class="Delimiter">(</span>i<span class="Delimiter">).</span><a href='010---vm.cc.html#L131'>match32</a><span class="Delimiter">(</span>addr<span class="Delimiter">))</span> <span class="Delimiter">{</span>
<span id="L237" class="LineNr">237 </span>      <span class="Normal">if</span> <span class="Delimiter">(</span>result<span class="Delimiter">)</span>
<span id="L238" class="LineNr">238 </span>        <a href='003trace.cc.html#L202'>raise</a> &lt;&lt; <span class="Constant">&quot;address 0x&quot;</span> &lt;&lt; <a href='010---vm.cc.html#L440'>HEXWORD</a> &lt;&lt; addr &lt;&lt; <span class="Constant">&quot; is in two segments\n&quot;</span> &lt;&lt; end<span class="Delimiter">();</span>
<span id="L239" class="LineNr">239 </span>      result = <span class="Normal">reinterpret_cast</span>&lt;<span class="Normal">uint32_t</span>*&gt;<span class="Delimiter">(</span>&amp;<span class="Special"><a href='010---vm.cc.html#L180'>Mem</a></span><span class="Delimiter">.</span>at<span class="Delimiter">(</span>i<span class="Delimiter">).</span>data<span class="Delimiter">(</span>addr<span class="Delimiter">));</span>
<span id="L240" class="LineNr">240 </span>    <span class="Delimiter">}</span>
<span id="L241" class="LineNr">241 </span>  <span class="Delimiter">}</span>
<span id="L242" class="LineNr">242 </span>  <span class="Normal">if</span> <span class="Delimiter">(</span>result == <span class="Constant">NULL</span><span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L243" class="LineNr">243 </span>    <a href='003trace.cc.html#L202'>raise</a> &lt;&lt; <span class="Constant">&quot;Tried to access uninitialized memory at address 0x&quot;</span> &lt;&lt; <a href='010---vm.cc.html#L440'>HEXWORD</a> &lt;&lt; addr &lt;&lt; <span class="cSpecial">'\n'</span> &lt;&lt; end<span class="Delimiter">();</span>
<span id="L244" class="LineNr">244 </span>    <a href='003trace.cc.html#L202'>raise</a> &lt;&lt; <span class="Constant">&quot;The entire 4-byte <a href='011run.cc.html#L126'>word</a> should be initialized and lie in a single segment.\n&quot;</span> &lt;&lt; end<span class="Delimiter">();</span>
<span id="L245" class="LineNr">245 </span>  <span class="Delimiter">}</span>
<span id="L246" class="LineNr">246 </span>  <span class="Identifier">return</span> result<span class="Delimiter">;</span>
<span id="L247" class="LineNr">247 </span><span class="Delimiter">}</span>
<span id="L248" class="LineNr">248 </span><span class="Normal">inline</span> <span class="Normal">int32_t</span>* <a href='010---vm.cc.html#L248'>mem_addr_i32</a><span class="Delimiter">(</span><span class="Normal">uint32_t</span> addr<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L249" class="LineNr">249 </span>  <span class="Identifier">return</span> <span class="Normal">reinterpret_cast</span>&lt;<span class="Normal">int32_t</span>*&gt;<span class="Delimiter">(</span><a href='010---vm.cc.html#L233'>mem_addr_u32</a><span class="Delimiter">(</span>addr<span class="Delimiter">));</span>
<span id="L250" class="LineNr">250 </span><span class="Delimiter">}</span>
<span id="L251" class="LineNr">251 </span><span class="Comment">// helper for some syscalls. But read-only.</span>
<span id="L252" class="LineNr">252 </span><span class="Normal">inline</span> <span class="Normal">const</span> <span class="Normal">char</span>* <a href='010---vm.cc.html#L252'>mem_addr_kernel_string</a><span class="Delimiter">(</span><span class="Normal">uint32_t</span> addr<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L253" class="LineNr">253 </span>  <span class="Identifier">return</span> <span class="Normal">reinterpret_cast</span>&lt;<span class="Normal">const</span> <span class="Normal">char</span>*&gt;<span class="Delimiter">(</span><a href='010---vm.cc.html#L217'>mem_addr_u8</a><span class="Delimiter">(</span>addr<span class="Delimiter">));</span>
<span id="L254" class="LineNr">254 </span><span class="Delimiter">}</span>
<span id="L255" class="LineNr">255 </span><span class="Normal">inline</span> string <a href='010---vm.cc.html#L255'>mem_addr_string</a><span class="Delimiter">(</span><span class="Normal">uint32_t</span> addr<span class="Delimiter">,</span> <span class="Normal">uint32_t</span> size<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L256" class="LineNr">256 </span>  ostringstream out<span class="Delimiter">;</span>
<span id="L257" class="LineNr">257 </span>  <span class="Normal">for</span> <span class="Delimiter">(</span><span class="Normal">size_t</span> i = <span class="Constant">0</span><span class="Delimiter">;</span>  i &lt; size<span class="Delimiter">;</span>  ++i<span class="Delimiter">)</span>
<span id="L258" class="LineNr">258 </span>    out &lt;&lt; <a href='010---vm.cc.html#L202'>read_mem_u8</a><span class="Delimiter">(</span>addr+i<span class="Delimiter">);</span>
<span id="L259" class="LineNr">259 </span>  <span class="Identifier">return</span> out<span class="Delimiter">.</span>str<span class="Delimiter">();</span>
<span id="L260" class="LineNr">260 </span><span class="Delimiter">}</span>
<span id="L261" class="LineNr">261 </span>
<span id="L262" class="LineNr">262 </span>
<span id="L263" class="LineNr">263 </span><span class="Normal">inline</span> <span class="Normal">void</span> <a href='010---vm.cc.html#L263'>write_mem_u8</a><span class="Delimiter">(</span><span class="Normal">uint32_t</span> addr<span class="Delimiter">,</span> <span class="Normal">uint8_t</span> val<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L264" class="LineNr">264 </span>  <span class="Normal">uint8_t</span>* handle = <a href='010---vm.cc.html#L217'>mem_addr_u8</a><span class="Delimiter">(</span>addr<span class="Delimiter">);</span>
<span id="L265" class="LineNr">265 </span>  <span class="Normal">if</span> <span class="Delimiter">(</span>handle != <span class="Constant">NULL</span><span class="Delimiter">)</span> *handle = val<span class="Delimiter">;</span>
<span id="L266" class="LineNr">266 </span><span class="Delimiter">}</span>
<span id="L267" class="LineNr">267 </span><span class="Normal">inline</span> <span class="Normal">void</span> <a href='010---vm.cc.html#L267'>write_mem_i8</a><span class="Delimiter">(</span><span class="Normal">uint32_t</span> addr<span class="Delimiter">,</span> <span class="Normal">int8_t</span> val<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L268" class="LineNr">268 </span>  <span class="Normal">int8_t</span>* handle = <a href='010---vm.cc.html#L230'>mem_addr_i8</a><span class="Delimiter">(</span>addr<span class="Delimiter">);</span>
<span id="L269" class="LineNr">269 </span>  <span class="Normal">if</span> <span class="Delimiter">(</span>handle != <span class="Constant">NULL</span><span class="Delimiter">)</span> *handle = val<span class="Delimiter">;</span>
<span id="L270" class="LineNr">270 </span><span class="Delimiter">}</span>
<span id="L271" class="LineNr">271 </span><span class="Normal">inline</span> <span class="Normal">void</span> <a href='010---vm.cc.html#L271'>write_mem_u32</a><span class="Delimiter">(</span><span class="Normal">uint32_t</span> addr<span class="Delimiter">,</span> <span class="Normal">uint32_t</span> val<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L272" class="LineNr">272 </span>  <span class="Normal">uint32_t</span>* handle = <a href='010---vm.cc.html#L233'>mem_addr_u32</a><span class="Delimiter">(</span>addr<span class="Delimiter">);</span>
<span id="L273" class="LineNr">273 </span>  <span class="Normal">if</span> <span class="Delimiter">(</span>handle != <span class="Constant">NULL</span><span class="Delimiter">)</span> *handle = val<span class="Delimiter">;</span>
<span id="L274" class="LineNr">274 </span><span class="Delimiter">}</span>
<span id="L275" class="LineNr">275 </span><span class="Normal">inline</span> <span class="Normal">void</span> <a href='010---vm.cc.html#L275'>write_mem_i32</a><span class="Delimiter">(</span><span class="Normal">uint32_t</span> addr<span class="Delimiter">,</span> <span class="Normal">int32_t</span> val<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L276" class="LineNr">276 </span>  <span class="Normal">int32_t</span>* handle = <a href='010---vm.cc.html#L248'>mem_addr_i32</a><span class="Delimiter">(</span>addr<span class="Delimiter">);</span>
<span id="L277" class="LineNr">277 </span>  <span class="Normal">if</span> <span class="Delimiter">(</span>handle != <span class="Constant">NULL</span><span class="Delimiter">)</span> *handle = val<span class="Delimiter">;</span>
<span id="L278" class="LineNr">278 </span><span class="Delimiter">}</span>
<span id="L279" class="LineNr">279 </span>
<span id="L280" class="LineNr">280 </span><span class="Normal">inline</span> <span class="Normal">bool</span> <a href='010---vm.cc.html#L280'>already_allocated</a><span class="Delimiter">(</span><span class="Normal">uint32_t</span> addr<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L281" class="LineNr">281 </span>  <span class="Normal">bool</span> result = <span class="Constant">false</span><span class="Delimiter">;</span>
<span id="L282" class="LineNr">282 </span>  <span class="Normal">for</span> <span class="Delimiter">(</span><span class="Normal">int</span> i = <span class="Constant">0</span><span class="Delimiter">;</span>  i &lt; <a href='001help.cc.html#L166'>SIZE</a><span class="Delimiter">(</span><span class="Special"><a href='010---vm.cc.html#L180'>Mem</a></span><span class="Delimiter">);</span>  ++i<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L283" class="LineNr">283 </span>    <span class="Normal">if</span> <span class="Delimiter">(</span><span class="Special"><a href='010---vm.cc.html#L180'>Mem</a></span><span class="Delimiter">.</span>at<span class="Delimiter">(</span>i<span class="Delimiter">).</span><a href='010---vm.cc.html#L128'>match</a><span class="Delimiter">(</span>addr<span class="Delimiter">))</span> <span class="Delimiter">{</span>
<span id="L284" class="LineNr">284 </span>      <span class="Normal">if</span> <span class="Delimiter">(</span>result<span class="Delimiter">)</span>
<span id="L285" class="LineNr">285 </span>        <a href='003trace.cc.html#L202'>raise</a> &lt;&lt; <span class="Constant">&quot;address 0x&quot;</span> &lt;&lt; <a href='010---vm.cc.html#L440'>HEXWORD</a> &lt;&lt; addr &lt;&lt; <span class="Constant">&quot; is in two segments\n&quot;</span> &lt;&lt; end<span class="Delimiter">();</span>
<span id="L286" class="LineNr">286 </span>      result = <span class="Constant">true</span><span class="Delimiter">;</span>
<span id="L287" class="LineNr">287 </span>    <span class="Delimiter">}</span>
<span id="L288" class="LineNr">288 </span>  <span class="Delimiter">}</span>
<span id="L289" class="LineNr">289 </span>  <span class="Identifier">return</span> result<span class="Delimiter">;</span>
<span id="L290" class="LineNr">290 </span><span class="Delimiter">}</span>
<span id="L291" class="LineNr">291 </span>
<span id="L292" class="LineNr">292 </span><span class="SalientComment">//:: core interpreter loop</span>
<span id="L293" class="LineNr">293 </span>
<span id="L294" class="LineNr">294 </span><span class="Delimiter">:(code)</span>
<span id="L295" class="LineNr">295 </span><span class="Comment">// skeleton of how x86 instructions are decoded</span>
<span id="L296" class="LineNr">296 </span><span class="Normal">void</span> <a href='010---vm.cc.html#L296'>run_one_instruction</a><span class="Delimiter">()</span> <span class="Delimiter">{</span>
<span id="L297" class="LineNr">297 </span>  <span class="Normal">uint8_t</span> op=<span class="Constant">0</span><span class="Delimiter">,</span> op2=<span class="Constant">0</span><span class="Delimiter">,</span> op3=<span class="Constant">0</span><span class="Delimiter">;</span>
<span id="L298" class="LineNr">298 </span>  <span class="Comment">// Run One Instruction</span>
<span id="L299" class="LineNr">299 </span>  <span class="Normal">if</span> <span class="Delimiter">(</span><span class="Special"><a href='003trace.cc.html#L421'>Trace_file</a></span><span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L300" class="LineNr">300 </span>    <a href='010---vm.cc.html#L367'>dump_registers</a><span class="Delimiter">();</span>
<span id="L301" class="LineNr">301 </span>    <span class="Comment">// End Dump Info for Instruction</span>
<span id="L302" class="LineNr">302 </span>  <span class="Delimiter">}</span>
<span id="L303" class="LineNr">303 </span>  <span class="Normal">uint32_t</span> inst_start_address = EIP<span class="Delimiter">;</span>
<span id="L304" class="LineNr">304 </span>  op = <a href='010---vm.cc.html#L363'>next</a><span class="Delimiter">();</span>
<span id="L305" class="LineNr">305 </span>  <a href='003trace.cc.html#L96'>trace</a><span class="Delimiter">(</span><span class="Special">Callstack_depth</span><span class="Delimiter">,</span> <span class="Constant">&quot;run&quot;</span><span class="Delimiter">)</span> &lt;&lt; <span class="Constant">&quot;0x&quot;</span> &lt;&lt; <a href='010---vm.cc.html#L440'>HEXWORD</a> &lt;&lt; inst_start_address &lt;&lt; <span class="Constant">&quot; opcode: &quot;</span> &lt;&lt; <a href='010---vm.cc.html#L439'>HEXBYTE</a> &lt;&lt; <a href='010---vm.cc.html#L442'>NUM</a><span class="Delimiter">(</span>op<span class="Delimiter">)</span> &lt;&lt; <a href='010---vm.cc.html#L379'>call_label</a><span class="Delimiter">(</span>op<span class="Delimiter">)</span> &lt;&lt; end<span class="Delimiter">();</span>
<span id="L306" class="LineNr">306 </span>  <span class="Normal">switch</span> <span class="Delimiter">(</span>op<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L307" class="LineNr">307 </span>  <span class="Normal">case</span> <span class="Constant">0xf4</span>:  <span class="Comment">// hlt</span>
<span id="L308" class="LineNr">308 </span>    EIP = <span class="Special"><a href='010---vm.cc.html#L194'>End_of_program</a></span><span class="Delimiter">;</span>
<span id="L309" class="LineNr">309 </span>    <span class="Identifier">break</span><span class="Delimiter">;</span>
<span id="L310" class="LineNr">310 </span>  <span class="Comment">// End Single-Byte Opcodes</span>
<span id="L311" class="LineNr">311 </span>  <span class="Normal">case</span> <span class="Constant">0x0f</span>:
<span id="L312" class="LineNr">312 </span>    <span class="Normal">switch</span><span class="Delimiter">(</span>op2 = <a href='010---vm.cc.html#L363'>next</a><span class="Delimiter">())</span> <span class="Delimiter">{</span>
<span id="L313" class="LineNr">313 </span>    <span class="Comment">// End Two-Byte Opcodes Starting With 0f</span>
<span id="L314" class="LineNr">314 </span>    <span class="Normal">default</span>:
<span id="L315" class="LineNr">315 </span>      cerr &lt;&lt; <span class="Constant">&quot;unrecognized second opcode after 0f: &quot;</span> &lt;&lt; <a href='010---vm.cc.html#L439'>HEXBYTE</a> &lt;&lt; <a href='010---vm.cc.html#L442'>NUM</a><span class="Delimiter">(</span>op2<span class="Delimiter">)</span> &lt;&lt; <span class="cSpecial">'\n'</span><span class="Delimiter">;</span>
<span id="L316" class="LineNr">316 </span>      <a href='003trace.cc.html#L410'>DUMP</a><span class="Delimiter">(</span><span class="Constant">&quot;&quot;</span><span class="Delimiter">);</span>
<span id="L317" class="LineNr">317 </span>      exit<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">);</span>
<span id="L318" class="LineNr">318 </span>    <span class="Delimiter">}</span>
<span id="L319" class="LineNr">319 </span>    <span class="Identifier">break</span><span class="Delimiter">;</span>
<span id="L320" class="LineNr">320 </span>  <span class="Normal">case</span> <span class="Constant">0xf2</span>:
<span id="L321" class="LineNr">321 </span>    <span class="Normal">switch</span><span class="Delimiter">(</span>op2 = <a href='010---vm.cc.html#L363'>next</a><span class="Delimiter">())</span> <span class="Delimiter">{</span>
<span id="L322" class="LineNr">322 </span>    <span class="Comment">// End Two-Byte Opcodes Starting With f2</span>
<span id="L323" class="LineNr">323 </span>    <span class="Normal">case</span> <span class="Constant">0x0f</span>:
<span id="L324" class="LineNr">324 </span>      <span class="Normal">switch</span><span class="Delimiter">(</span>op3 = <a href='010---vm.cc.html#L363'>next</a><span class="Delimiter">())</span> <span class="Delimiter">{</span>
<span id="L325" class="LineNr">325 </span>      <span class="Comment">// End Three-Byte Opcodes Starting With f2 0f</span>
<span id="L326" class="LineNr">326 </span>      <span class="Normal">default</span>:
<span id="L327" class="LineNr">327 </span>        cerr &lt;&lt; <span class="Constant">&quot;unrecognized third opcode after f2 0f: &quot;</span> &lt;&lt; <a href='010---vm.cc.html#L439'>HEXBYTE</a> &lt;&lt; <a href='010---vm.cc.html#L442'>NUM</a><span class="Delimiter">(</span>op3<span class="Delimiter">)</span> &lt;&lt; <span class="cSpecial">'\n'</span><span class="Delimiter">;</span>
<span id="L328" class="LineNr">328 </span>        <a href='003trace.cc.html#L410'>DUMP</a><span class="Delimiter">(</span><span class="Constant">&quot;&quot;</span><span class="Delimiter">);</span>
<span id="L329" class="LineNr">329 </span>        exit<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">);</span>
<span id="L330" class="LineNr">330 </span>      <span class="Delimiter">}</span>
<span id="L331" class="LineNr">331 </span>      <span class="Identifier">break</span><span class="Delimiter">;</span>
<span id="L332" class="LineNr">332 </span>    <span class="Normal">default</span>:
<span id="L333" class="LineNr">333 </span>      cerr &lt;&lt; <span class="Constant">&quot;unrecognized second opcode after f2: &quot;</span> &lt;&lt; <a href='010---vm.cc.html#L439'>HEXBYTE</a> &lt;&lt; <a href='010---vm.cc.html#L442'>NUM</a><span class="Delimiter">(</span>op2<span class="Delimiter">)</span> &lt;&lt; <span class="cSpecial">'\n'</span><span class="Delimiter">;</span>
<span id="L334" class="LineNr">334 </span>      <a href='003trace.cc.html#L410'>DUMP</a><span class="Delimiter">(</span><span class="Constant">&quot;&quot;</span><span class="Delimiter">);</span>
<span id="L335" class="LineNr">335 </span>      exit<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">);</span>
<span id="L336" class="LineNr">336 </span>    <span class="Delimiter">}</span>
<span id="L337" class="LineNr">337 </span>    <span class="Identifier">break</span><span class="Delimiter">;</span>
<span id="L338" class="LineNr">338 </span>  <span class="Normal">case</span> <span class="Constant">0xf3</span>:
<span id="L339" class="LineNr">339 </span>    <span class="Normal">switch</span><span class="Delimiter">(</span>op2 = <a href='010---vm.cc.html#L363'>next</a><span class="Delimiter">())</span> <span class="Delimiter">{</span>
<span id="L340" class="LineNr">340 </span>    <span class="Comment">// End Two-Byte Opcodes Starting With f3</span>
<span id="L341" class="LineNr">341 </span>    <span class="Normal">case</span> <span class="Constant">0x0f</span>:
<span id="L342" class="LineNr">342 </span>      <span class="Normal">switch</span><span class="Delimiter">(</span>op3 = <a href='010---vm.cc.html#L363'>next</a><span class="Delimiter">())</span> <span class="Delimiter">{</span>
<span id="L343" class="LineNr">343 </span>      <span class="Comment">// End Three-Byte Opcodes Starting With f3 0f</span>
<span id="L344" class="LineNr">344 </span>      <span class="Normal">default</span>:
<span id="L345" class="LineNr">345 </span>        cerr &lt;&lt; <span class="Constant">&quot;unrecognized third opcode after f3 0f: &quot;</span> &lt;&lt; <a href='010---vm.cc.html#L439'>HEXBYTE</a> &lt;&lt; <a href='010---vm.cc.html#L442'>NUM</a><span class="Delimiter">(</span>op3<span class="Delimiter">)</span> &lt;&lt; <span class="cSpecial">'\n'</span><span class="Delimiter">;</span>
<span id="L346" class="LineNr">346 </span>        <a href='003trace.cc.html#L410'>DUMP</a><span class="Delimiter">(</span><span class="Constant">&quot;&quot;</span><span class="Delimiter">);</span>
<span id="L347" class="LineNr">347 </span>        exit<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">);</span>
<span id="L348" class="LineNr">348 </span>      <span class="Delimiter">}</span>
<span id="L349" class="LineNr">349 </span>      <span class="Identifier">break</span><span class="Delimiter">;</span>
<span id="L350" class="LineNr">350 </span>    <span class="Normal">default</span>:
<span id="L351" class="LineNr">351 </span>      cerr &lt;&lt; <span class="Constant">&quot;unrecognized second opcode after f3: &quot;</span> &lt;&lt; <a href='010---vm.cc.html#L439'>HEXBYTE</a> &lt;&lt; <a href='010---vm.cc.html#L442'>NUM</a><span class="Delimiter">(</span>op2<span class="Delimiter">)</span> &lt;&lt; <span class="cSpecial">'\n'</span><span class="Delimiter">;</span>
<span id="L352" class="LineNr">352 </span>      <a href='003trace.cc.html#L410'>DUMP</a><span class="Delimiter">(</span><span class="Constant">&quot;&quot;</span><span class="Delimiter">);</span>
<span id="L353" class="LineNr">353 </span>      exit<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">);</span>
<span id="L354" class="LineNr">354 </span>    <span class="Delimiter">}</span>
<span id="L355" class="LineNr">355 </span>    <span class="Identifier">break</span><span class="Delimiter">;</span>
<span id="L356" class="LineNr">356 </span>  <span class="Normal">default</span>:
<span id="L357" class="LineNr">357 </span>    cerr &lt;&lt; <span class="Constant">&quot;unrecognized opcode: &quot;</span> &lt;&lt; <a href='010---vm.cc.html#L439'>HEXBYTE</a> &lt;&lt; <a href='010---vm.cc.html#L442'>NUM</a><span class="Delimiter">(</span>op<span class="Delimiter">)</span> &lt;&lt; <span class="cSpecial">'\n'</span><span class="Delimiter">;</span>
<span id="L358" class="LineNr">358 </span>    <a href='003trace.cc.html#L410'>DUMP</a><span class="Delimiter">(</span><span class="Constant">&quot;&quot;</span><span class="Delimiter">);</span>
<span id="L359" class="LineNr">359 </span>    exit<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">);</span>
<span id="L360" class="LineNr">360 </span>  <span class="Delimiter">}</span>
<span id="L361" class="LineNr">361 </span><span class="Delimiter">}</span>
<span id="L362" class="LineNr">362 </span>
<span id="L363" class="LineNr">363 </span><span class="Normal">inline</span> <span class="Normal">uint8_t</span> <a href='010---vm.cc.html#L363'>next</a><span class="Delimiter">()</span> <span class="Delimiter">{</span>
<span id="L364" class="LineNr">364 </span>  <span class="Identifier">return</span> <a href='010---vm.cc.html#L202'>read_mem_u8</a><span class="Delimiter">(</span>EIP++<span class="Delimiter">);</span>
<span id="L365" class="LineNr">365 </span><span class="Delimiter">}</span>
<span id="L366" class="LineNr">366 </span>
<span id="L367" class="LineNr">367 </span><span class="Normal">void</span> <a href='010---vm.cc.html#L367'>dump_registers</a><span class="Delimiter">()</span> <span class="Delimiter">{</span>
<span id="L368" class="LineNr">368 </span>  ostringstream out<span class="Delimiter">;</span>
<span id="L369" class="LineNr">369 </span>  out &lt;&lt; <span class="Constant">&quot;registers: &quot;</span><span class="Delimiter">;</span>
<span id="L370" class="LineNr">370 </span>  <span class="Normal">for</span> <span class="Delimiter">(</span><span class="Normal">int</span> i = <span class="Constant">0</span><span class="Delimiter">;</span>  i &lt; <a href='010---vm.cc.html#L21'>NUM_INT_REGISTERS</a><span class="Delimiter">;</span>  ++i<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L371" class="LineNr">371 </span>    <span class="Normal">if</span> <span class="Delimiter">(</span>i &gt; <span class="Constant">0</span><span class="Delimiter">)</span> out &lt;&lt; <span class="Constant">&quot;; &quot;</span><span class="Delimiter">;</span>
<span id="L372" class="LineNr">372 </span>    out &lt;&lt; <span class="Constant">&quot;  &quot;</span> &lt;&lt; i &lt;&lt; <span class="Constant">&quot;: &quot;</span> &lt;&lt; std::hex &lt;&lt; std::setw<span class="Delimiter">(</span><span class="Constant">8</span><span class="Delimiter">)</span> &lt;&lt; std::setfill<span class="Delimiter">(</span><span class="Constant">'_'</span><span class="Delimiter">)</span> &lt;&lt; <span class="Special"><a href='010---vm.cc.html#L28'>Reg</a></span>[i]<span class="Delimiter">.</span>u<span class="Delimiter">;</span>
<span id="L373" class="LineNr">373 </span>  <span class="Delimiter">}</span>
<span id="L374" class="LineNr">374 </span>  out &lt;&lt; <span class="Constant">&quot; -- SF: &quot;</span> &lt;&lt; SF &lt;&lt; <span class="Constant">&quot;; <a href='010---vm.cc.html#L80'>ZF</a>: &quot;</span> &lt;&lt; <a href='010---vm.cc.html#L80'>ZF</a> &lt;&lt; <span class="Constant">&quot;; <a href='010---vm.cc.html#L81'>OF</a>: &quot;</span> &lt;&lt; <a href='010---vm.cc.html#L81'>OF</a><span class="Delimiter">;</span>
<span id="L375" class="LineNr">375 </span>  <a href='003trace.cc.html#L96'>trace</a><span class="Delimiter">(</span><span class="Special">Callstack_depth</span>+<span class="Constant">1</span><span class="Delimiter">,</span> <span class="Constant">&quot;run&quot;</span><span class="Delimiter">)</span> &lt;&lt; out<span class="Delimiter">.</span>str<span class="Delimiter">()</span> &lt;&lt; end<span class="Delimiter">();</span>
<span id="L376" class="LineNr">376 </span><span class="Delimiter">}</span>
<span id="L377" class="LineNr">377 </span>
<span id="L378" class="LineNr">378 </span><span class="Comment">// debugging info from a later layer</span>
<span id="L379" class="LineNr">379 </span>string <a href='010---vm.cc.html#L379'>call_label</a><span class="Delimiter">(</span><span class="Normal">uint8_t</span> op<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L380" class="LineNr">380 </span>  <span class="Normal">if</span> <span class="Delimiter">(</span>op != <span class="Constant">0xe8</span><span class="Delimiter">)</span> <span class="Identifier">return</span> <span class="Constant">&quot;&quot;</span><span class="Delimiter">;</span>
<span id="L381" class="LineNr">381 </span>  <span class="Comment">// End Trace Call Instruction</span>
<span id="L382" class="LineNr">382 </span>  <span class="Identifier">return</span> <span class="Constant">&quot;/call&quot;</span><span class="Delimiter">;</span>
<span id="L383" class="LineNr">383 </span><span class="Delimiter">}</span>
<span id="L384" class="LineNr">384 </span>
<span id="L385" class="LineNr">385 </span><span class="Comment">//: start tracking supported opcodes</span>
<span id="L386" class="LineNr">386 </span><span class="Delimiter">:(before &quot;End Globals&quot;)</span>
<span id="L387" class="LineNr">387 </span>map&lt;<span class="Comment">/*</span><span class="Comment">op</span><span class="Comment">*/</span>string<span class="Delimiter">,</span> string&gt; <span class="Special"><a href='010---vm.cc.html#L387'>Name</a></span><span class="Delimiter">;</span>
<span id="L388" class="LineNr">388 </span>map&lt;<span class="Comment">/*</span><span class="Comment">op</span><span class="Comment">*/</span>string<span class="Delimiter">,</span> string&gt; <span class="Special"><a href='010---vm.cc.html#L388'>Name_0f</a></span><span class="Delimiter">;</span>
<span id="L389" class="LineNr">389 </span>map&lt;<span class="Comment">/*</span><span class="Comment">op</span><span class="Comment">*/</span>string<span class="Delimiter">,</span> string&gt; <span class="Special"><a href='010---vm.cc.html#L389'>Name_f3</a></span><span class="Delimiter">;</span>
<span id="L390" class="LineNr">390 </span>map&lt;<span class="Comment">/*</span><span class="Comment">op</span><span class="Comment">*/</span>string<span class="Delimiter">,</span> string&gt; <span class="Special"><a href='010---vm.cc.html#L390'>Name_f3_0f</a></span><span class="Delimiter">;</span>
<span id="L391" class="LineNr">391 </span><span class="Delimiter">:(before &quot;End One-time Setup&quot;)</span>
<span id="L392" class="LineNr">392 </span><a href='010---vm.cc.html#L394'>init_op_names</a><span class="Delimiter">();</span>
<span id="L393" class="LineNr">393 </span><span class="Delimiter">:(code)</span>
<span id="L394" class="LineNr">394 </span><span class="Normal">void</span> <a href='010---vm.cc.html#L394'>init_op_names</a><span class="Delimiter">()</span> <span class="Delimiter">{</span>
<span id="L395" class="LineNr">395 </span>  <a href='001help.cc.html#L252'>put</a><span class="Delimiter">(</span><span class="Special"><a href='010---vm.cc.html#L387'>Name</a></span><span class="Delimiter">,</span> <span class="Constant">&quot;f4&quot;</span><span class="Delimiter">,</span> <span class="Constant">&quot;halt (hlt)&quot;</span><span class="Delimiter">);</span>
<span id="L396" class="LineNr">396 </span>  <span class="Comment">// End Initialize Op Names</span>
<span id="L397" class="LineNr">397 </span><span class="Delimiter">}</span>
<span id="L398" class="LineNr">398 </span>
<span id="L399" class="LineNr">399 </span><span class="Delimiter">:(before &quot;End <a href='001help.cc.html#L53'>Help</a> Special-cases(key)&quot;)</span>
<span id="L400" class="LineNr">400 </span><span class="Normal">if</span> <span class="Delimiter">(</span>key == <span class="Constant">&quot;opcodes&quot;</span><span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L401" class="LineNr">401 </span>  cerr &lt;&lt; <span class="Constant">&quot;Opcodes currently supported by SubX:\n&quot;</span><span class="Delimiter">;</span>
<span id="L402" class="LineNr">402 </span>  <span class="Normal">for</span> <span class="Delimiter">(</span>map&lt;string<span class="Delimiter">,</span> string&gt;::iterator p = <span class="Special"><a href='010---vm.cc.html#L387'>Name</a></span><span class="Delimiter">.</span>begin<span class="Delimiter">();</span>  p != <span class="Special"><a href='010---vm.cc.html#L387'>Name</a></span><span class="Delimiter">.</span>end<span class="Delimiter">();</span>  ++p<span class="Delimiter">)</span>
<span id="L403" class="LineNr">403 </span>    cerr &lt;&lt; <span class="Constant">&quot;  &quot;</span> &lt;&lt; p<span class="Delimiter">-&gt;</span>first &lt;&lt; <span class="Constant">&quot;: &quot;</span> &lt;&lt; p<span class="Delimiter">-&gt;</span>second &lt;&lt; <span class="cSpecial">'\n'</span><span class="Delimiter">;</span>
<span id="L404" class="LineNr">404 </span>  <span class="Normal">for</span> <span class="Delimiter">(</span>map&lt;string<span class="Delimiter">,</span> string&gt;::iterator p = <span class="Special"><a href='010---vm.cc.html#L388'>Name_0f</a></span><span class="Delimiter">.</span>begin<span class="Delimiter">();</span>  p != <span class="Special"><a href='010---vm.cc.html#L388'>Name_0f</a></span><span class="Delimiter">.</span>end<span class="Delimiter">();</span>  ++p<span class="Delimiter">)</span>
<span id="L405" class="LineNr">405 </span>    cerr &lt;&lt; <span class="Constant">&quot;  0f &quot;</span> &lt;&lt; p<span class="Delimiter">-&gt;</span>first &lt;&lt; <span class="Constant">&quot;: &quot;</span> &lt;&lt; p<span class="Delimiter">-&gt;</span>second &lt;&lt; <span class="cSpecial">'\n'</span><span class="Delimiter">;</span>
<span id="L406" class="LineNr">406 </span>  <span class="Normal">for</span> <span class="Delimiter">(</span>map&lt;string<span class="Delimiter">,</span> string&gt;::iterator p = <span class="Special"><a href='010---vm.cc.html#L389'>Name_f3</a></span><span class="Delimiter">.</span>begin<span class="Delimiter">();</span>  p != <span class="Special"><a href='010---vm.cc.html#L389'>Name_f3</a></span><span class="Delimiter">.</span>end<span class="Delimiter">();</span>  ++p<span class="Delimiter">)</span>
<span id="L407" class="LineNr">407 </span>    cerr &lt;&lt; <span class="Constant">&quot;  f3 &quot;</span> &lt;&lt; p<span class="Delimiter">-&gt;</span>first &lt;&lt; <span class="Constant">&quot;: &quot;</span> &lt;&lt; p<span class="Delimiter">-&gt;</span>second &lt;&lt; <span class="cSpecial">'\n'</span><span class="Delimiter">;</span>
<span id="L408" class="LineNr">408 </span>  <span class="Normal">for</span> <span class="Delimiter">(</span>map&lt;string<span class="Delimiter">,</span> string&gt;::iterator p = <span class="Special"><a href='010---vm.cc.html#L390'>Name_f3_0f</a></span><span class="Delimiter">.</span>begin<span class="Delimiter">();</span>  p != <span class="Special"><a href='010---vm.cc.html#L390'>Name_f3_0f</a></span><span class="Delimiter">.</span>end<span class="Delimiter">();</span>  ++p<span class="Delimiter">)</span>
<span id="L409" class="LineNr">409 </span>    cerr &lt;&lt; <span class="Constant">&quot;  f3 0f &quot;</span> &lt;&lt; p<span class="Delimiter">-&gt;</span>first &lt;&lt; <span class="Constant">&quot;: &quot;</span> &lt;&lt; p<span class="Delimiter">-&gt;</span>second &lt;&lt; <span class="cSpecial">'\n'</span><span class="Delimiter">;</span>
<span id="L410" class="LineNr">410 </span>  cerr &lt;&lt; <span class="Constant">&quot;Run `subx help instructions` for details on <a href='011run.cc.html#L121'>words</a> like 'r32' and 'disp8'.\n&quot;</span>
<span id="L411" class="LineNr">411 </span>          <span class="Constant">&quot;For complete details on these instructions, consult the IA-32 manual (volume 2).\n&quot;</span>
<span id="L412" class="LineNr">412 </span>          <span class="Constant">&quot;There's various versions of it online, such as <a href="https://c9x.me/x86.">https://c9x.me/x86.</a>\n&quot;</span>
<span id="L413" class="LineNr">413 </span>          <span class="Constant">&quot;The mnemonics in brackets will help you locate each instruction.\n&quot;</span><span class="Delimiter">;</span>
<span id="L414" class="LineNr">414 </span>  <span class="Identifier">return</span> <span class="Constant">0</span><span class="Delimiter">;</span>
<span id="L415" class="LineNr">415 </span><span class="Delimiter">}</span>
<span id="L416" class="LineNr">416 </span><span class="Delimiter">:(before &quot;End <a href='001help.cc.html#L53'>Help</a> Contents&quot;)</span>
<span id="L417" class="LineNr">417 </span>cerr &lt;&lt; <span class="Constant">&quot;  opcodes\n&quot;</span><span class="Delimiter">;</span>
<span id="L418" class="LineNr">418 </span>
<span id="L419" class="LineNr">419 </span><span class="Comment">//: Helpers for managing trace depths</span>
<span id="L420" class="LineNr">420 </span><span class="Comment">//:</span>
<span id="L421" class="LineNr">421 </span><span class="Comment">//: We're going to use trace depths primarily to segment code running at</span>
<span id="L422" class="LineNr">422 </span><span class="Comment">//: different frames of the call stack. This will make it easy for the trace</span>
<span id="L423" class="LineNr">423 </span><span class="Comment">//: browser to collapse over entire calls.</span>
<span id="L424" class="LineNr">424 </span><span class="Comment">//:</span>
<span id="L425" class="LineNr">425 </span><span class="Comment">//: Errors will be at depth 0.</span>
<span id="L426" class="LineNr">426 </span><span class="Comment">//: Warnings will be at depth 1.</span>
<span id="L427" class="LineNr">427 </span><span class="Comment">//: SubX instructions will occupy depth 2 and up to Max_depth, organized by</span>
<span id="L428" class="LineNr">428 </span><span class="Comment">//: stack frames. Each instruction's internal details will be one level deeper</span>
<span id="L429" class="LineNr">429 </span><span class="Comment">//: than its 'main' depth. So 'call' instruction details will be at the same</span>
<span id="L430" class="LineNr">430 </span><span class="Comment">//: depth as the instructions of the function it calls.</span>
<span id="L431" class="LineNr">431 </span><span class="Delimiter">:(before &quot;End Globals&quot;)</span>
<span id="L432" class="LineNr">432 </span><span class="Normal">extern</span> <span class="Normal">const</span> <span class="Normal">int</span> <span class="Special"><a href='010---vm.cc.html#L432'>Initial_callstack_depth</a></span> = <span class="Constant">2</span><span class="Delimiter">;</span>
<span id="L433" class="LineNr">433 </span><span class="Normal">int</span> <span class="Special">Callstack_depth</span> = <span class="Special"><a href='010---vm.cc.html#L432'>Initial_callstack_depth</a></span><span class="Delimiter">;</span>
<span id="L434" class="LineNr">434 </span><span class="Delimiter">:(before &quot;End Reset&quot;)</span>
<span id="L435" class="LineNr">435 </span><span class="Special">Callstack_depth</span> = <span class="Special"><a href='010---vm.cc.html#L432'>Initial_callstack_depth</a></span><span class="Delimiter">;</span>
<span id="L436" class="LineNr">436 </span>
<span id="L437" class="LineNr">437 </span><span class="Delimiter">:(before &quot;End Includes&quot;)</span>
<span id="L438" class="LineNr">438 </span><span class="PreProc">#include </span><span class="Constant">&lt;iomanip&gt;</span>
<span id="L439" class="LineNr">439 </span><span class="PreProc">#define HEXBYTE  std::hex &lt;&lt; std::setw(</span><span class="Constant">2</span><span class="PreProc">) &lt;&lt; std::setfill(</span><span class="Constant">'0'</span><span class="PreProc">)</span>
<span id="L440" class="LineNr">440 </span><span class="PreProc">#define HEXWORD  std::hex &lt;&lt; std::setw(</span><span class="Constant">8</span><span class="PreProc">) &lt;&lt; std::setfill(</span><span class="Constant">'0'</span><span class="PreProc">)</span>
<span id="L441" class="LineNr">441 </span><span class="Comment">// ugly that iostream doesn't print uint8_t as an integer</span>
<span id="L442" class="LineNr">442 </span><span class="PreProc">#define NUM(</span><span class="Special">X</span><span class="PreProc">) </span><span class="Normal">static_cast</span><span class="PreProc">&lt;</span><span class="Normal">int</span><span class="PreProc">&gt;(</span><span class="Special">X</span><span class="PreProc">)</span>
<span id="L443" class="LineNr">443 </span><span class="PreProc">#include </span><span class="Constant">&lt;stdint.h&gt;</span>
</pre>
</body>
</html>
<!-- vim: set foldmethod=manual : -->