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authorKartik Agaram <vc@akkartik.com>2018-10-17 07:08:47 -0700
committerKartik Agaram <vc@akkartik.com>2018-10-17 07:08:47 -0700
commit104e521c04d1a0cad9c68fb11e250e12ad8917ef (patch)
treedf4258ad26cb78e25abee64c80aedab47aa461ea /html/subx/010---vm.cc.html
parent800320a70c981008302af56b2f35a142c1101401 (diff)
downloadmu-104e521c04d1a0cad9c68fb11e250e12ad8917ef.tar.gz
4709
Diffstat (limited to 'html/subx/010---vm.cc.html')
-rw-r--r--html/subx/010---vm.cc.html702
1 files changed, 368 insertions, 334 deletions
diff --git a/html/subx/010---vm.cc.html b/html/subx/010---vm.cc.html
index ad6efb36..b48e3f87 100644
--- a/html/subx/010---vm.cc.html
+++ b/html/subx/010---vm.cc.html
@@ -18,7 +18,6 @@ a:hover { text-decoration: underline; }
 .cSpecial { color: #008000; }
 .LineNr { color: #444444; }
 .Constant { color: #00a0a0; }
-.CommentedCode { color: #6c6c6c; }
 .Delimiter { color: #800080; }
 .Identifier { color: #c0a020; }
 .Normal { color: #aaaaaa; background-color: #080808; padding-bottom: 1px; }
@@ -95,341 +94,376 @@ if ('onhashchange' in window) {
 <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</span><span class="cSpecial">\n</span><span class="Constant">&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#L243'>put</a><span class="Delimiter">(</span><a href='001help.cc.html#L53'>Help</a><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: R0 to R7.</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
-<span id="L39" class="LineNr"> 39 </span>  <span class="Constant">&quot;R4 (ESP) contains the top of the stack.</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
-<span id="L40" class="LineNr"> 40 </span>  <span class="Constant">&quot;</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
-<span id="L41" class="LineNr"> 41 </span>  <span class="Constant">&quot;There's also a register for the address of the currently executing</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
-<span id="L42" class="LineNr"> 42 </span>  <span class="Constant">&quot;instruction. It is modified by jumps.</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
-<span id="L43" class="LineNr"> 43 </span>  <span class="Constant">&quot;</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
-<span id="L44" class="LineNr"> 44 </span>  <span class="Constant">&quot;Various instructions modify one or more of three 1-bit 'flag' registers,</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
-<span id="L45" class="LineNr"> 45 </span>  <span class="Constant">&quot;as a side-effect:</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
-<span id="L46" class="LineNr"> 46 </span>  <span class="Constant">&quot;- the sign flag (SF): usually set if an arithmetic result is negative, or</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
-<span id="L47" class="LineNr"> 47 </span>  <span class="Constant">&quot;  <a href='000organization.cc.html#L148'>reset</a> if not.</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
-<span id="L48" class="LineNr"> 48 </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.</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
-<span id="L49" class="LineNr"> 49 </span>  <span class="Constant">&quot;- the overflow flag (OF): usually set if an arithmetic result overflows.</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
-<span id="L50" class="LineNr"> 50 </span>  <span class="Constant">&quot;The flag bits are read by conditional jumps.</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
-<span id="L51" class="LineNr"> 51 </span>  <span class="Constant">&quot;</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
-<span id="L52" class="LineNr"> 52 </span>  <span class="Constant">&quot;We don't support non-integer (floating-point) registers yet.</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
-<span id="L53" class="LineNr"> 53 </span><span class="Delimiter">);</span>
-<span id="L54" class="LineNr"> 54 </span>
-<span id="L55" class="LineNr"> 55 </span><span class="Delimiter">:(before &quot;End Globals&quot;)</span>
-<span id="L56" class="LineNr"> 56 </span><span class="Comment">// the subset of x86 flag registers we care about</span>
-<span id="L57" class="LineNr"> 57 </span><span class="Normal">bool</span> SF =<span class="Constant"> false</span><span class="Delimiter">;</span>  <span class="Comment">// sign flag</span>
-<span id="L58" class="LineNr"> 58 </span><span class="Normal">bool</span> ZF =<span class="Constant"> false</span><span class="Delimiter">;</span>  <span class="Comment">// zero flag</span>
-<span id="L59" class="LineNr"> 59 </span><span class="Normal">bool</span> <a href='010---vm.cc.html#L59'>OF</a> =<span class="Constant"> false</span><span class="Delimiter">;</span>  <span class="Comment">// overflow flag</span>
-<span id="L60" class="LineNr"> 60 </span><span class="Delimiter">:(before &quot;End Reset&quot;)</span>
-<span id="L61" class="LineNr"> 61 </span>SF = ZF = <a href='010---vm.cc.html#L59'>OF</a> =<span class="Constant"> false</span><span class="Delimiter">;</span>
-<span id="L62" class="LineNr"> 62 </span>
-<span id="L63" class="LineNr"> 63 </span><span class="Comment">//: how the flag registers are updated after each instruction</span>
-<span id="L64" class="LineNr"> 64 </span>
-<span id="L65" class="LineNr"> 65 </span><span class="Delimiter">:(before &quot;End Includes&quot;)</span>
-<span id="L66" class="LineNr"> 66 </span><span class="Comment">// Combine 'arg1' and 'arg2' with arithmetic operation 'op' and store the</span>
-<span id="L67" class="LineNr"> 67 </span><span class="Comment">// result in 'arg1', then update flags.</span>
-<span id="L68" class="LineNr"> 68 </span><span class="Comment">// beware: no side-effects in args</span>
-<span id="L69" class="LineNr"> 69 </span><span class="Comment">#define BINARY_ARITHMETIC_OP(op, arg1, arg2) { \</span>
-<span id="L70" class="LineNr"> 70 </span>  <span class="Comment">/*</span><span class="Comment"> arg1 and arg2 must be signed </span><span class="Comment">*/</span> \
-<span id="L71" class="LineNr"> 71 </span>  <span class="Normal">int64_t</span> tmp = arg1 op arg2<span class="Delimiter">;</span> \
-<span id="L72" class="LineNr"> 72 </span>  arg1 = arg1 op arg2<span class="Delimiter">;</span> \
-<span id="L73" class="LineNr"> 73 </span>  <a href='003trace.cc.html#L204'>trace</a><span class="Delimiter">(</span><span class="Constant">90</span><span class="Delimiter">,</span> <span class="Constant">&quot;run&quot;</span><span class="Delimiter">)</span> &lt;&lt; <span class="Constant">&quot;storing 0x&quot;</span> &lt;&lt; <a href='010---vm.cc.html#L368'>HEXWORD</a> &lt;&lt; arg1 &lt;&lt; end<span class="Delimiter">();</span> \
-<span id="L74" class="LineNr"> 74 </span>  SF = <span class="Delimiter">(</span>arg1 &lt; <span class="Constant">0</span><span class="Delimiter">);</span> \
-<span id="L75" class="LineNr"> 75 </span>  ZF = <span class="Delimiter">(</span>arg1 == <span class="Constant">0</span><span class="Delimiter">);</span> \
-<span id="L76" class="LineNr"> 76 </span>  <a href='010---vm.cc.html#L59'>OF</a> = <span class="Delimiter">(</span>arg1 != tmp<span class="Delimiter">);</span> \
-<span id="L77" class="LineNr"> 77 </span><span class="Delimiter">}</span>
-<span id="L78" class="LineNr"> 78 </span>
-<span id="L79" class="LineNr"> 79 </span><span class="Comment">// Combine 'arg1' and 'arg2' with bitwise operation 'op' and store the result</span>
-<span id="L80" class="LineNr"> 80 </span><span class="Comment">// in 'arg1', then update flags.</span>
-<span id="L81" class="LineNr"> 81 </span><span class="Comment">#define BINARY_BITWISE_OP(op, arg1, arg2) { \</span>
-<span id="L82" class="LineNr"> 82 </span>  <span class="Comment">/*</span><span class="Comment"> arg1 and arg2 must be unsigned </span><span class="Comment">*/</span> \
-<span id="L83" class="LineNr"> 83 </span>  arg1 = arg1 op arg2<span class="Delimiter">;</span> \
-<span id="L84" class="LineNr"> 84 </span>  <a href='003trace.cc.html#L204'>trace</a><span class="Delimiter">(</span><span class="Constant">90</span><span class="Delimiter">,</span> <span class="Constant">&quot;run&quot;</span><span class="Delimiter">)</span> &lt;&lt; <span class="Constant">&quot;storing 0x&quot;</span> &lt;&lt; <a href='010---vm.cc.html#L368'>HEXWORD</a> &lt;&lt; arg1 &lt;&lt; end<span class="Delimiter">();</span> \
-<span id="L85" class="LineNr"> 85 </span>  SF = <span class="Delimiter">(</span>arg1 &gt;&gt; <span class="Constant">31</span><span class="Delimiter">);</span> \
-<span id="L86" class="LineNr"> 86 </span>  ZF = <span class="Delimiter">(</span>arg1 == <span class="Constant">0</span><span class="Delimiter">);</span> \
-<span id="L87" class="LineNr"> 87 </span>  <a href='010---vm.cc.html#L59'>OF</a> =<span class="Constant"> false</span><span class="Delimiter">;</span> \
-<span id="L88" class="LineNr"> 88 </span><span class="Delimiter">}</span>
-<span id="L89" class="LineNr"> 89 </span>
-<span id="L90" class="LineNr"> 90 </span><span class="SalientComment">//:: simulated RAM</span>
-<span id="L91" class="LineNr"> 91 </span>
-<span id="L92" class="LineNr"> 92 </span><span class="Delimiter">:(before &quot;End Types&quot;)</span>
-<span id="L93" class="LineNr"> 93 </span><span class="Normal">const</span> <span class="Normal">uint32_t</span> <a href='010---vm.cc.html#L93'>INITIAL_SEGMENT_SIZE</a> = <span class="Constant">0x1000</span> - <span class="Constant">1</span><span class="Delimiter">;</span>
-<span id="L94" class="LineNr"> 94 </span><span class="Comment">// Subtract one just so we can start the first segment at address 1 without</span>
-<span id="L95" class="LineNr"> 95 </span><span class="Comment">// overflowing the first segment. Other segments will learn to adjust.</span>
-<span id="L96" class="LineNr"> 96 </span>
-<span id="L97" class="LineNr"> 97 </span><span class="Comment">// Like in real-world Linux, we'll allocate RAM for our programs in disjoint</span>
-<span id="L98" class="LineNr"> 98 </span><span class="Comment">// slabs called VMAs or Virtual Memory Areas.</span>
-<span id="L99" class="LineNr"> 99 </span><span class="Normal">struct</span> vma <span class="Delimiter">{</span>
-<span id="L100" class="LineNr">100 </span>  <span class="Normal">uint32_t</span> start<span class="Delimiter">;</span>  <span class="Comment">// inclusive</span>
-<span id="L101" class="LineNr">101 </span>  <span class="Normal">uint32_t</span> end<span class="Delimiter">;</span>  <span class="Comment">// exclusive</span>
-<span id="L102" class="LineNr">102 </span>  vector&lt;<span class="Normal">uint8_t</span>&gt; <a href='010---vm.cc.html#L102'>_data</a><span class="Delimiter">;</span>
-<span id="L103" class="LineNr">103 </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="L104" class="LineNr">104 </span>    <a href='010---vm.cc.html#L102'>_data</a><span class="Delimiter">.</span>resize<span class="Delimiter">(</span>end-start<span class="Delimiter">);</span>
-<span id="L105" class="LineNr">105 </span>  <span class="Delimiter">}</span>
-<span id="L106" class="LineNr">106 </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>s+INITIAL_SEGMENT_SIZE<span class="Delimiter">)</span> <span class="Delimiter">{</span>
-<span id="L107" class="LineNr">107 </span>    <a href='010---vm.cc.html#L102'>_data</a><span class="Delimiter">.</span>resize<span class="Delimiter">(</span>end-start<span class="Delimiter">);</span>
-<span id="L108" class="LineNr">108 </span>  <span class="Delimiter">}</span>
-<span id="L109" class="LineNr">109 </span>  <span class="Normal">bool</span> <a href='010---vm.cc.html#L109'>match</a><span class="Delimiter">(</span><span class="Normal">uint32_t</span> a<span class="Delimiter">)</span> <span class="Delimiter">{</span>
-<span id="L110" class="LineNr">110 </span>    <span class="Identifier">return</span> a &gt;= start &amp;&amp; a &lt; end<span class="Delimiter">;</span>
-<span id="L111" class="LineNr">111 </span>  <span class="Delimiter">}</span>
-<span id="L112" class="LineNr">112 </span>  <span class="Normal">bool</span> <a href='010---vm.cc.html#L112'>match32</a><span class="Delimiter">(</span><span class="Normal">uint32_t</span> a<span class="Delimiter">)</span> <span class="Delimiter">{</span>
-<span id="L113" class="LineNr">113 </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="L114" class="LineNr">114 </span>  <span class="Delimiter">}</span>
-<span id="L115" class="LineNr">115 </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="L116" class="LineNr">116 </span>    assert<span class="Delimiter">(</span><a href='010---vm.cc.html#L109'>match</a><span class="Delimiter">(</span>a<span class="Delimiter">));</span>
-<span id="L117" class="LineNr">117 </span>    <span class="Identifier">return</span> <a href='010---vm.cc.html#L102'>_data</a><span class="Delimiter">.</span>at<span class="Delimiter">(</span>a-start<span class="Delimiter">);</span>
-<span id="L118" class="LineNr">118 </span>  <span class="Delimiter">}</span>
-<span id="L119" class="LineNr">119 </span>  <span class="Normal">void</span> <a href='010---vm.cc.html#L119'>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="L120" class="LineNr">120 </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="L121" class="LineNr">121 </span>    <span class="Comment">// Ugly: vma knows about the global Memory list of vmas</span>
-<span id="L122" class="LineNr">122 </span>    <span class="Normal">void</span> <a href='010---vm.cc.html#L130'>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="L123" class="LineNr">123 </span>    <a href='010---vm.cc.html#L130'>sanity_check</a><span class="Delimiter">(</span>start<span class="Delimiter">,</span> new_end_address<span class="Delimiter">);</span>
-<span id="L124" class="LineNr">124 </span>    end = new_end_address<span class="Delimiter">;</span>
-<span id="L125" class="LineNr">125 </span>    <a href='010---vm.cc.html#L102'>_data</a><span class="Delimiter">.</span>resize<span class="Delimiter">(</span>new_end_address - start<span class="Delimiter">);</span>
-<span id="L126" class="LineNr">126 </span>  <span class="Delimiter">}</span>
-<span id="L127" class="LineNr">127 </span>  <span class="Comment">// End vma Methods</span>
-<span id="L128" class="LineNr">128 </span><span class="Delimiter">};</span>
-<span id="L129" class="LineNr">129 </span><span class="Delimiter">:(code)</span>
-<span id="L130" class="LineNr">130 </span><span class="Normal">void</span> <a href='010---vm.cc.html#L130'>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="L131" class="LineNr">131 </span>  <span class="Normal">bool</span> dup_found =<span class="Constant"> false</span><span class="Delimiter">;</span>
-<span id="L132" class="LineNr">132 </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#L157'>SIZE</a><span class="Delimiter">(</span><a href='010---vm.cc.html#L149'>Mem</a><span class="Delimiter">);</span>  ++i<span class="Delimiter">)</span> <span class="Delimiter">{</span>
-<span id="L133" class="LineNr">133 </span>    <span class="Normal">const</span> vma&amp; curr = <a href='010---vm.cc.html#L149'>Mem</a><span class="Delimiter">.</span>at<span class="Delimiter">(</span>i<span class="Delimiter">);</span>
-<span id="L134" class="LineNr">134 </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="L135" class="LineNr">135 </span>      assert<span class="Delimiter">(</span>!dup_found<span class="Delimiter">);</span>
-<span id="L136" class="LineNr">136 </span>      dup_found =<span class="Constant"> true</span><span class="Delimiter">;</span>
-<span id="L137" class="LineNr">137 </span>    <span class="Delimiter">}</span>
-<span id="L138" class="LineNr">138 </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="L139" class="LineNr">139 </span>      assert<span class="Delimiter">(</span>curr<span class="Delimiter">.</span>start &gt; end<span class="Delimiter">);</span>
-<span id="L140" class="LineNr">140 </span>    <span class="Delimiter">}</span>
-<span id="L141" class="LineNr">141 </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="L142" class="LineNr">142 </span>      assert<span class="Delimiter">(</span>curr<span class="Delimiter">.</span>end &lt; start<span class="Delimiter">);</span>
-<span id="L143" class="LineNr">143 </span>    <span class="Delimiter">}</span>
-<span id="L144" class="LineNr">144 </span>  <span class="Delimiter">}</span>
-<span id="L145" class="LineNr">145 </span><span class="Delimiter">}</span>
-<span id="L146" class="LineNr">146 </span>
-<span id="L147" class="LineNr">147 </span><span class="Delimiter">:(before &quot;End Globals&quot;)</span>
-<span id="L148" class="LineNr">148 </span><span class="Comment">// RAM is made of VMAs.</span>
-<span id="L149" class="LineNr">149 </span>vector&lt;vma&gt; <a href='010---vm.cc.html#L149'>Mem</a><span class="Delimiter">;</span>
-<span id="L150" class="LineNr">150 </span><span class="Delimiter">:(code)</span>
-<span id="L151" class="LineNr">151 </span><span class="Comment">// The first 3 VMAs are special. When loading ELF binaries in later layers,</span>
-<span id="L152" class="LineNr">152 </span><span class="Comment">// we'll assume that the first VMA is for code, the second is for data</span>
-<span id="L153" class="LineNr">153 </span><span class="Comment">// (including the heap), and the third for the stack.</span>
-<span id="L154" class="LineNr">154 </span><span class="Normal">void</span> <a href='010---vm.cc.html#L154'>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="L155" class="LineNr">155 </span>  assert<span class="Delimiter">(</span>!Mem<span class="Delimiter">.</span>empty<span class="Delimiter">());</span>
-<span id="L156" class="LineNr">156 </span>  <a href='010---vm.cc.html#L149'>Mem</a><span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">).</span><a href='010---vm.cc.html#L119'>grow_until</a><span class="Delimiter">(</span>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="Normal">void</span> <a href='010---vm.cc.html#L158'>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="L159" class="LineNr">159 </span>  assert<span class="Delimiter">(</span><a href='001help.cc.html#L157'>SIZE</a><span class="Delimiter">(</span><a href='010---vm.cc.html#L149'>Mem</a><span class="Delimiter">)</span> &gt; <span class="Constant">1</span><span class="Delimiter">);</span>
-<span id="L160" class="LineNr">160 </span>  <a href='010---vm.cc.html#L149'>Mem</a><span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">).</span><a href='010---vm.cc.html#L119'>grow_until</a><span class="Delimiter">(</span>new_end_address<span class="Delimiter">);</span>
-<span id="L161" class="LineNr">161 </span><span class="Delimiter">}</span>
-<span id="L162" class="LineNr">162 </span><span class="Delimiter">:(before &quot;End Globals&quot;)</span>
-<span id="L163" class="LineNr">163 </span><span class="Normal">uint32_t</span> <a href='010---vm.cc.html#L163'>End_of_program</a> = <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="L164" class="LineNr">164 </span><span class="Comment">// The stack grows downward. Can't increase its size for now.</span>
-<span id="L165" class="LineNr">165 </span><span class="Delimiter">:(before &quot;End Reset&quot;)</span>
-<span id="L166" class="LineNr">166 </span><a href='010---vm.cc.html#L149'>Mem</a><span class="Delimiter">.</span>clear<span class="Delimiter">();</span>
-<span id="L167" class="LineNr">167 </span><a href='010---vm.cc.html#L163'>End_of_program</a> = <span class="Constant">0</span><span class="Delimiter">;</span>
-<span id="L168" class="LineNr">168 </span><span class="Delimiter">:(code)</span>
-<span id="L169" class="LineNr">169 </span><span class="Comment">// These helpers depend on Mem being laid out contiguously (so you can't use a</span>
-<span id="L170" class="LineNr">170 </span><span class="Comment">// map, etc.) and on the host also being little-endian.</span>
-<span id="L171" class="LineNr">171 </span><span class="Normal">inline</span> <span class="Normal">uint8_t</span> <a href='010---vm.cc.html#L171'>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="L172" class="LineNr">172 </span>  <span class="Normal">uint8_t</span>* handle = <a href='010---vm.cc.html#L186'>mem_addr_u8</a><span class="Delimiter">(</span>addr<span class="Delimiter">);</span>  <span class="Comment">// error messages get printed here</span>
-<span id="L173" class="LineNr">173 </span>  <span class="Identifier">return</span> handle ? *handle : <span class="Constant">0</span><span class="Delimiter">;</span>
-<span id="L174" class="LineNr">174 </span><span class="Delimiter">}</span>
-<span id="L175" class="LineNr">175 </span><span class="Normal">inline</span> <span class="Normal">int8_t</span> <a href='010---vm.cc.html#L175'>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="L176" class="LineNr">176 </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#L171'>read_mem_u8</a><span class="Delimiter">(</span>addr<span class="Delimiter">));</span>
-<span id="L177" class="LineNr">177 </span><span class="Delimiter">}</span>
-<span id="L178" class="LineNr">178 </span><span class="Normal">inline</span> <span class="Normal">uint32_t</span> <a href='010---vm.cc.html#L178'>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="L179" class="LineNr">179 </span>  <span class="Normal">uint32_t</span>* handle = <a href='010---vm.cc.html#L202'>mem_addr_u32</a><span class="Delimiter">(</span>addr<span class="Delimiter">);</span>  <span class="Comment">// error messages get printed here</span>
-<span id="L180" class="LineNr">180 </span>  <span class="Identifier">return</span> handle ? *handle : <span class="Constant">0</span><span class="Delimiter">;</span>
-<span id="L181" class="LineNr">181 </span><span class="Delimiter">}</span>
-<span id="L182" class="LineNr">182 </span><span class="Normal">inline</span> <span class="Normal">int32_t</span> <a href='010---vm.cc.html#L182'>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="L183" class="LineNr">183 </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#L178'>read_mem_u32</a><span class="Delimiter">(</span>addr<span class="Delimiter">));</span>
-<span id="L184" class="LineNr">184 </span><span class="Delimiter">}</span>
-<span id="L185" class="LineNr">185 </span>
-<span id="L186" class="LineNr">186 </span><span class="Normal">inline</span> <span class="Normal">uint8_t</span>* <a href='010---vm.cc.html#L186'>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="L187" class="LineNr">187 </span>  <span class="Normal">uint8_t</span>* result = <span class="Constant">NULL</span><span class="Delimiter">;</span>
-<span id="L188" class="LineNr">188 </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#L157'>SIZE</a><span class="Delimiter">(</span><a href='010---vm.cc.html#L149'>Mem</a><span class="Delimiter">);</span>  ++i<span class="Delimiter">)</span> <span class="Delimiter">{</span>
-<span id="L189" class="LineNr">189 </span>    <span class="Normal">if</span> <span class="Delimiter">(</span><a href='010---vm.cc.html#L149'>Mem</a><span class="Delimiter">.</span>at<span class="Delimiter">(</span>i<span class="Delimiter">).</span><a href='010---vm.cc.html#L109'>match</a><span class="Delimiter">(</span>addr<span class="Delimiter">))</span> <span class="Delimiter">{</span>
-<span id="L190" class="LineNr">190 </span>      <span class="Normal">if</span> <span class="Delimiter">(</span>result<span class="Delimiter">)</span>
-<span id="L191" class="LineNr">191 </span>        <a href='003trace.cc.html#L211'>raise</a> &lt;&lt; <span class="Constant">&quot;address 0x&quot;</span> &lt;&lt; <a href='010---vm.cc.html#L368'>HEXWORD</a> &lt;&lt; addr &lt;&lt; <span class="Constant">&quot; is in two <a href='011run.cc.html#L100'>segments</a></span><span class="cSpecial">\n</span><span class="Constant">&quot;</span> &lt;&lt; end<span class="Delimiter">();</span>
-<span id="L192" class="LineNr">192 </span>      result = &amp;Mem<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="L193" class="LineNr">193 </span>    <span class="Delimiter">}</span>
-<span id="L194" class="LineNr">194 </span>  <span class="Delimiter">}</span>
-<span id="L195" class="LineNr">195 </span>  <span class="Normal">if</span> <span class="Delimiter">(</span>result == <span class="Constant">NULL</span><span class="Delimiter">)</span>
-<span id="L196" class="LineNr">196 </span>    <a href='003trace.cc.html#L211'>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#L368'>HEXWORD</a> &lt;&lt; addr &lt;&lt; <span class="cSpecial">'\n'</span> &lt;&lt; end<span class="Delimiter">();</span>
-<span id="L197" class="LineNr">197 </span>  <span class="Identifier">return</span> result<span class="Delimiter">;</span>
-<span id="L198" class="LineNr">198 </span><span class="Delimiter">}</span>
-<span id="L199" class="LineNr">199 </span><span class="Normal">inline</span> <span class="Normal">int8_t</span>* <a href='010---vm.cc.html#L199'>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="L200" class="LineNr">200 </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#L186'>mem_addr_u8</a><span class="Delimiter">(</span>addr<span class="Delimiter">));</span>
-<span id="L201" class="LineNr">201 </span><span class="Delimiter">}</span>
-<span id="L202" class="LineNr">202 </span><span class="Normal">inline</span> <span class="Normal">uint32_t</span>* <a href='010---vm.cc.html#L202'>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="L203" class="LineNr">203 </span>  <span class="Normal">uint32_t</span>* result = <span class="Constant">NULL</span><span class="Delimiter">;</span>
-<span id="L204" class="LineNr">204 </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#L157'>SIZE</a><span class="Delimiter">(</span><a href='010---vm.cc.html#L149'>Mem</a><span class="Delimiter">);</span>  ++i<span class="Delimiter">)</span> <span class="Delimiter">{</span>
-<span id="L205" class="LineNr">205 </span>    <span class="Normal">if</span> <span class="Delimiter">(</span><a href='010---vm.cc.html#L149'>Mem</a><span class="Delimiter">.</span>at<span class="Delimiter">(</span>i<span class="Delimiter">).</span><a href='010---vm.cc.html#L112'>match32</a><span class="Delimiter">(</span>addr<span class="Delimiter">))</span> <span class="Delimiter">{</span>
-<span id="L206" class="LineNr">206 </span>      <span class="Normal">if</span> <span class="Delimiter">(</span>result<span class="Delimiter">)</span>
-<span id="L207" class="LineNr">207 </span>        <a href='003trace.cc.html#L211'>raise</a> &lt;&lt; <span class="Constant">&quot;address 0x&quot;</span> &lt;&lt; <a href='010---vm.cc.html#L368'>HEXWORD</a> &lt;&lt; addr &lt;&lt; <span class="Constant">&quot; is in two <a href='011run.cc.html#L100'>segments</a></span><span class="cSpecial">\n</span><span class="Constant">&quot;</span> &lt;&lt; end<span class="Delimiter">();</span>
-<span id="L208" class="LineNr">208 </span>      result = <span class="Normal">reinterpret_cast</span>&lt;<span class="Normal">uint32_t</span>*&gt;<span class="Delimiter">(</span>&amp;Mem<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="L209" class="LineNr">209 </span>    <span class="Delimiter">}</span>
-<span id="L210" class="LineNr">210 </span>  <span class="Delimiter">}</span>
-<span id="L211" class="LineNr">211 </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="L212" class="LineNr">212 </span>    <a href='003trace.cc.html#L211'>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#L368'>HEXWORD</a> &lt;&lt; addr &lt;&lt; <span class="cSpecial">'\n'</span> &lt;&lt; end<span class="Delimiter">();</span>
-<span id="L213" class="LineNr">213 </span>    <a href='003trace.cc.html#L211'>raise</a> &lt;&lt; <span class="Constant">&quot;The entire 4-byte <a href='011run.cc.html#L123'>word</a> should be initialized and lie in a single segment.</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span> &lt;&lt; end<span class="Delimiter">();</span>
-<span id="L214" class="LineNr">214 </span>  <span class="Delimiter">}</span>
-<span id="L215" class="LineNr">215 </span>  <span class="Identifier">return</span> result<span class="Delimiter">;</span>
-<span id="L216" class="LineNr">216 </span><span class="Delimiter">}</span>
-<span id="L217" class="LineNr">217 </span><span class="Normal">inline</span> <span class="Normal">int32_t</span>* <a href='010---vm.cc.html#L217'>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="L218" class="LineNr">218 </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#L202'>mem_addr_u32</a><span class="Delimiter">(</span>addr<span class="Delimiter">));</span>
-<span id="L219" class="LineNr">219 </span><span class="Delimiter">}</span>
-<span id="L220" class="LineNr">220 </span><span class="Comment">// helper for some syscalls. But read-only.</span>
-<span id="L221" class="LineNr">221 </span><span class="Normal">inline</span> <span class="Normal">const</span> <span class="Normal">char</span>* <a href='010---vm.cc.html#L221'>mem_addr_string</a><span class="Delimiter">(</span><span class="Normal">uint32_t</span> addr<span class="Delimiter">)</span> <span class="Delimiter">{</span>
-<span id="L222" class="LineNr">222 </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#L186'>mem_addr_u8</a><span class="Delimiter">(</span>addr<span class="Delimiter">));</span>
+<span id="L37" class="LineNr"> 37 </span><a href='001help.cc.html#L253'>put_new</a><span class="Delimiter">(</span><a href='001help.cc.html#L53'>Help</a><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:</span><span class="cSpecial">\n</span><span class="Constant">&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> <a href='010---vm.cc.html#L20'>EDI</a></span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
+<span id="L40" class="LineNr"> 40 </span>  <span class="Constant">&quot;ESP contains the top of the stack.</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
+<span id="L41" class="LineNr"> 41 </span>  <span class="Constant">&quot;</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
+<span id="L42" class="LineNr"> 42 </span>  <span class="Constant">&quot;-- 8-bit registers</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
+<span id="L43" class="LineNr"> 43 </span>  <span class="Constant">&quot;Some instructions operate on eight *overlapping* 8-bit registers.</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
+<span id="L44" class="LineNr"> 44 </span>  <span class="Constant">&quot;From 0 to 7, they are:</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
+<span id="L45" class="LineNr"> 45 </span>  <span class="Constant">&quot;  AL CL DL BL AH CH DH BH</span><span class="cSpecial">\n</span><span class="Constant">&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</span><span class="cSpecial">\n</span><span class="Constant">&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.</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
+<span id="L48" class="LineNr"> 48 </span>  <span class="Constant">&quot;</span><span class="cSpecial">\n</span><span class="Constant">&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.</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
+<span id="L50" class="LineNr"> 50 </span>  <span class="Constant">&quot;</span><span class="cSpecial">\n</span><span class="Constant">&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.</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
+<span id="L52" class="LineNr"> 52 </span>  <span class="Constant">&quot;</span><span class="cSpecial">\n</span><span class="Constant">&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,</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
+<span id="L54" class="LineNr"> 54 </span>  <span class="Constant">&quot;table 2-2, </span><span class="cSpecial">\&quot;</span><span class="Constant">32-bit addressing forms with the ModR/M byte</span><span class="cSpecial">\&quot;</span><span class="Constant">.</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
+<span id="L55" class="LineNr"> 55 </span>  <span class="Constant">&quot;It is included in this repository as 'modrm.pdf'.</span><span class="cSpecial">\n</span><span class="Constant">&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</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
+<span id="L57" class="LineNr"> 57 </span>  <span class="Constant">&quot;to spend some time with it.</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
+<span id="L58" class="LineNr"> 58 </span>  <span class="Constant">&quot;</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
+<span id="L59" class="LineNr"> 59 </span>  <span class="Constant">&quot;-- flag registers</span><span class="cSpecial">\n</span><span class="Constant">&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'</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
+<span id="L61" class="LineNr"> 61 </span>  <span class="Constant">&quot;registers, as a side-effect:</span><span class="cSpecial">\n</span><span class="Constant">&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</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
+<span id="L63" class="LineNr"> 63 </span>  <span class="Constant">&quot;  <a href='000organization.cc.html#L148'>reset</a> if not.</span><span class="cSpecial">\n</span><span class="Constant">&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.</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
+<span id="L65" class="LineNr"> 65 </span>  <span class="Constant">&quot;- the overflow flag (OF): usually set if an arithmetic result overflows.</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
+<span id="L66" class="LineNr"> 66 </span>  <span class="Constant">&quot;The flag bits are read by conditional jumps.</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
+<span id="L67" class="LineNr"> 67 </span>  <span class="Constant">&quot;</span><span class="cSpecial">\n</span><span class="Constant">&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</span><span class="cSpecial">\n</span><span class="Constant">&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>,</span><span class="cSpecial">\n</span><span class="Constant">&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</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
+<span id="L71" class="LineNr"> 71 </span>  <span class="Constant">&quot;that SubX doesn't support.</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
+<span id="L72" class="LineNr"> 72 </span>  <span class="Constant">&quot;</span><span class="cSpecial">\n</span><span class="Constant">&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,</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
+<span id="L74" class="LineNr"> 74 </span>  <span class="Constant">&quot;might as well get good at it.</span><span class="cSpecial">\n</span><span class="Constant">&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> ZF =<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 = ZF = <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="Comment">#define BINARY_ARITHMETIC_OP(op, arg1, arg2) { \</span>
+<span id="L92" class="LineNr"> 92 </span>  <span class="Comment">/*</span><span class="Comment"> arg1 and arg2 must be signed </span><span class="Comment">*/</span> \
+<span id="L93" class="LineNr"> 93 </span>  <span class="Normal">int64_t</span> tmp = arg1 op arg2<span class="Delimiter">;</span> \
+<span id="L94" class="LineNr"> 94 </span>  arg1 = arg1 op arg2<span class="Delimiter">;</span> \
+<span id="L95" class="LineNr"> 95 </span>  <a href='003trace.cc.html#L203'>trace</a><span class="Delimiter">(</span><span class="Constant">90</span><span class="Delimiter">,</span> <span class="Constant">&quot;run&quot;</span><span class="Delimiter">)</span> &lt;&lt; <span class="Constant">&quot;storing 0x&quot;</span> &lt;&lt; <a href='010---vm.cc.html#L403'>HEXWORD</a> &lt;&lt; arg1 &lt;&lt; end<span class="Delimiter">();</span> \
+<span id="L96" class="LineNr"> 96 </span>  SF = <span class="Delimiter">(</span>arg1 &lt; <span class="Constant">0</span><span class="Delimiter">);</span> \
+<span id="L97" class="LineNr"> 97 </span>  ZF = <span class="Delimiter">(</span>arg1 == <span class="Constant">0</span><span class="Delimiter">);</span> \
+<span id="L98" class="LineNr"> 98 </span>  <a href='010---vm.cc.html#L81'>OF</a> = <span class="Delimiter">(</span>arg1 != tmp<span class="Delimiter">);</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="Comment">#define BINARY_BITWISE_OP(op, arg1, arg2) { \</span>
+<span id="L104" class="LineNr">104 </span>  <span class="Comment">/*</span><span class="Comment"> arg1 and arg2 must be unsigned </span><span class="Comment">*/</span> \
+<span id="L105" class="LineNr">105 </span>  arg1 = arg1 op arg2<span class="Delimiter">;</span> \
+<span id="L106" class="LineNr">106 </span>  <a href='003trace.cc.html#L203'>trace</a><span class="Delimiter">(</span><span class="Constant">90</span><span class="Delimiter">,</span> <span class="Constant">&quot;run&quot;</span><span class="Delimiter">)</span> &lt;&lt; <span class="Constant">&quot;storing 0x&quot;</span> &lt;&lt; <a href='010---vm.cc.html#L403'>HEXWORD</a> &lt;&lt; arg1 &lt;&lt; end<span class="Delimiter">();</span> \
+<span id="L107" class="LineNr">107 </span>  SF = <span class="Delimiter">(</span>arg1 &gt;&gt; <span class="Constant">31</span><span class="Delimiter">);</span> \
+<span id="L108" class="LineNr">108 </span>  ZF = <span class="Delimiter">(</span>arg1 == <span class="Constant">0</span><span class="Delimiter">);</span> \
+<span id="L109" class="LineNr">109 </span>  <a href='010---vm.cc.html#L81'>OF</a> =<span class="Constant"> false</span><span class="Delimiter">;</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'>INITIAL_SEGMENT_SIZE</a> = <span class="Constant">0x1000</span> - <span class="Constant">1</span><span class="Delimiter">;</span>
+<span id="L116" class="LineNr">116 </span><span class="Comment">// Subtract one just so we can start the first segment at address 1 without</span>
+<span id="L117" class="LineNr">117 </span><span class="Comment">// overflowing the first segment. Other segments will learn to adjust.</span>
+<span id="L118" class="LineNr">118 </span>
+<span id="L119" class="LineNr">119 </span><span class="Comment">// Like in real-world Linux, we'll allocate RAM for our programs in disjoint</span>
+<span id="L120" class="LineNr">120 </span><span class="Comment">// slabs called VMAs or Virtual Memory Areas.</span>
+<span id="L121" class="LineNr">121 </span><span class="Normal">struct</span> vma <span class="Delimiter">{</span>
+<span id="L122" class="LineNr">122 </span>  <span class="Normal">uint32_t</span> start<span class="Delimiter">;</span>  <span class="Comment">// inclusive</span>
+<span id="L123" class="LineNr">123 </span>  <span class="Normal">uint32_t</span> end<span class="Delimiter">;</span>  <span class="Comment">// exclusive</span>
+<span id="L124" class="LineNr">124 </span>  vector&lt;<span class="Normal">uint8_t</span>&gt; <a href='010---vm.cc.html#L124'>_data</a><span class="Delimiter">;</span>
+<span id="L125" class="LineNr">125 </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="L126" class="LineNr">126 </span>    <a href='010---vm.cc.html#L124'>_data</a><span class="Delimiter">.</span>resize<span class="Delimiter">(</span>end-start<span class="Delimiter">);</span>
+<span id="L127" class="LineNr">127 </span>  <span class="Delimiter">}</span>
+<span id="L128" class="LineNr">128 </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>s+INITIAL_SEGMENT_SIZE<span class="Delimiter">)</span> <span class="Delimiter">{</span>
+<span id="L129" class="LineNr">129 </span>    <a href='010---vm.cc.html#L124'>_data</a><span class="Delimiter">.</span>resize<span class="Delimiter">(</span>end-start<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'>match</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 &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">bool</span> <a href='010---vm.cc.html#L134'>match32</a><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>    <span class="Identifier">return</span> a &gt;= start &amp;&amp; a+<span class="Constant">4</span> &lt;= end<span class="Delimiter">;</span>
+<span id="L136" class="LineNr">136 </span>  <span class="Delimiter">}</span>
+<span id="L137" class="LineNr">137 </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="L138" class="LineNr">138 </span>    assert<span class="Delimiter">(</span><a href='010---vm.cc.html#L131'>match</a><span class="Delimiter">(</span>a<span class="Delimiter">));</span>
+<span id="L139" class="LineNr">139 </span>    <span class="Identifier">return</span> <a href='010---vm.cc.html#L124'>_data</a><span class="Delimiter">.</span>at<span class="Delimiter">(</span>a-start<span class="Delimiter">);</span>
+<span id="L140" class="LineNr">140 </span>  <span class="Delimiter">}</span>
+<span id="L141" class="LineNr">141 </span>  <span class="Normal">void</span> <a href='010---vm.cc.html#L141'>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="L142" class="LineNr">142 </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="L143" class="LineNr">143 </span>    <span class="Comment">// Ugly: vma knows about the global Memory list of vmas</span>
+<span id="L144" class="LineNr">144 </span>    <span class="Normal">void</span> <a href='010---vm.cc.html#L152'>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="L145" class="LineNr">145 </span>    <a href='010---vm.cc.html#L152'>sanity_check</a><span class="Delimiter">(</span>start<span class="Delimiter">,</span> new_end_address<span class="Delimiter">);</span>
+<span id="L146" class="LineNr">146 </span>    end = new_end_address<span class="Delimiter">;</span>
+<span id="L147" class="LineNr">147 </span>    <a href='010---vm.cc.html#L124'>_data</a><span class="Delimiter">.</span>resize<span class="Delimiter">(</span>new_end_address - start<span class="Delimiter">);</span>
+<span id="L148" class="LineNr">148 </span>  <span class="Delimiter">}</span>
+<span id="L149" class="LineNr">149 </span>  <span class="Comment">// End vma Methods</span>
+<span id="L150" class="LineNr">150 </span><span class="Delimiter">};</span>
+<span id="L151" class="LineNr">151 </span><span class="Delimiter">:(code)</span>
+<span id="L152" class="LineNr">152 </span><span class="Normal">void</span> <a href='010---vm.cc.html#L152'>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="L153" class="LineNr">153 </span>  <span class="Normal">bool</span> dup_found =<span class="Constant"> false</span><span class="Delimiter">;</span>
+<span id="L154" class="LineNr">154 </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#L157'>SIZE</a><span class="Delimiter">(</span><a href='010---vm.cc.html#L171'>Mem</a><span class="Delimiter">);</span>  ++i<span class="Delimiter">)</span> <span class="Delimiter">{</span>
+<span id="L155" class="LineNr">155 </span>    <span class="Normal">const</span> vma&amp; curr = <a href='010---vm.cc.html#L171'>Mem</a><span class="Delimiter">.</span>at<span class="Delimiter">(</span>i<span class="Delimiter">);</span>
+<span id="L156" class="LineNr">156 </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="L157" class="LineNr">157 </span>      assert<span class="Delimiter">(</span>!dup_found<span class="Delimiter">);</span>
+<span id="L158" class="LineNr">158 </span>      dup_found =<span class="Constant"> true</span><span class="Delimiter">;</span>
+<span id="L159" class="LineNr">159 </span>    <span class="Delimiter">}</span>
+<span id="L160" class="LineNr">160 </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="L161" class="LineNr">161 </span>      assert<span class="Delimiter">(</span>curr<span class="Delimiter">.</span>start &gt; end<span class="Delimiter">);</span>
+<span id="L162" class="LineNr">162 </span>    <span class="Delimiter">}</span>
+<span id="L163" class="LineNr">163 </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="L164" class="LineNr">164 </span>      assert<span class="Delimiter">(</span>curr<span class="Delimiter">.</span>end &lt; start<span class="Delimiter">);</span>
+<span id="L165" class="LineNr">165 </span>    <span class="Delimiter">}</span>
+<span id="L166" class="LineNr">166 </span>  <span class="Delimiter">}</span>
+<span id="L167" class="LineNr">167 </span><span class="Delimiter">}</span>
+<span id="L168" class="LineNr">168 </span>
+<span id="L169" class="LineNr">169 </span><span class="Delimiter">:(before &quot;End Globals&quot;)</span>
+<span id="L170" class="LineNr">170 </span><span class="Comment">// RAM is made of VMAs.</span>
+<span id="L171" class="LineNr">171 </span>vector&lt;vma&gt; <a href='010---vm.cc.html#L171'>Mem</a><span class="Delimiter">;</span>
+<span id="L172" class="LineNr">172 </span><span class="Delimiter">:(code)</span>
+<span id="L173" class="LineNr">173 </span><span class="Comment">// The first 3 VMAs are special. When loading ELF binaries in later layers,</span>
+<span id="L174" class="LineNr">174 </span><span class="Comment">// we'll assume that the first VMA is for code, the second is for data</span>
+<span id="L175" class="LineNr">175 </span><span class="Comment">// (including the heap), and the third for the stack.</span>
+<span id="L176" class="LineNr">176 </span><span class="Normal">void</span> <a href='010---vm.cc.html#L176'>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="L177" class="LineNr">177 </span>  assert<span class="Delimiter">(</span>!Mem<span class="Delimiter">.</span>empty<span class="Delimiter">());</span>
+<span id="L178" class="LineNr">178 </span>  <a href='010---vm.cc.html#L171'>Mem</a><span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">).</span><a href='010---vm.cc.html#L141'>grow_until</a><span class="Delimiter">(</span>new_end_address<span class="Delimiter">);</span>
+<span id="L179" class="LineNr">179 </span><span class="Delimiter">}</span>
+<span id="L180" class="LineNr">180 </span><span class="Normal">void</span> <a href='010---vm.cc.html#L180'>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="L181" class="LineNr">181 </span>  assert<span class="Delimiter">(</span><a href='001help.cc.html#L157'>SIZE</a><span class="Delimiter">(</span><a href='010---vm.cc.html#L171'>Mem</a><span class="Delimiter">)</span> &gt; <span class="Constant">1</span><span class="Delimiter">);</span>
+<span id="L182" class="LineNr">182 </span>  <a href='010---vm.cc.html#L171'>Mem</a><span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">).</span><a href='010---vm.cc.html#L141'>grow_until</a><span class="Delimiter">(</span>new_end_address<span class="Delimiter">);</span>
+<span id="L183" class="LineNr">183 </span><span class="Delimiter">}</span>
+<span id="L184" class="LineNr">184 </span><span class="Delimiter">:(before &quot;End Globals&quot;)</span>
+<span id="L185" class="LineNr">185 </span><span class="Normal">uint32_t</span> <a href='010---vm.cc.html#L185'>End_of_program</a> = <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="L186" class="LineNr">186 </span><span class="Comment">// The stack grows downward. Can't increase its size for now.</span>
+<span id="L187" class="LineNr">187 </span><span class="Delimiter">:(before &quot;End Reset&quot;)</span>
+<span id="L188" class="LineNr">188 </span><a href='010---vm.cc.html#L171'>Mem</a><span class="Delimiter">.</span>clear<span class="Delimiter">();</span>
+<span id="L189" class="LineNr">189 </span><a href='010---vm.cc.html#L185'>End_of_program</a> = <span class="Constant">0</span><span class="Delimiter">;</span>
+<span id="L190" class="LineNr">190 </span><span class="Delimiter">:(code)</span>
+<span id="L191" class="LineNr">191 </span><span class="Comment">// These helpers depend on Mem being laid out contiguously (so you can't use a</span>
+<span id="L192" class="LineNr">192 </span><span class="Comment">// map, etc.) and on the host also being little-endian.</span>
+<span id="L193" class="LineNr">193 </span><span class="Normal">inline</span> <span class="Normal">uint8_t</span> <a href='010---vm.cc.html#L193'>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="L194" class="LineNr">194 </span>  <span class="Normal">uint8_t</span>* handle = <a href='010---vm.cc.html#L208'>mem_addr_u8</a><span class="Delimiter">(</span>addr<span class="Delimiter">);</span>  <span class="Comment">// error messages get printed here</span>
+<span id="L195" class="LineNr">195 </span>  <span class="Identifier">return</span> handle ? *handle : <span class="Constant">0</span><span class="Delimiter">;</span>
+<span id="L196" class="LineNr">196 </span><span class="Delimiter">}</span>
+<span id="L197" class="LineNr">197 </span><span class="Normal">inline</span> <span class="Normal">int8_t</span> <a href='010---vm.cc.html#L197'>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="L198" class="LineNr">198 </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#L193'>read_mem_u8</a><span class="Delimiter">(</span>addr<span class="Delimiter">));</span>
+<span id="L199" class="LineNr">199 </span><span class="Delimiter">}</span>
+<span id="L200" class="LineNr">200 </span><span class="Normal">inline</span> <span class="Normal">uint32_t</span> <a href='010---vm.cc.html#L200'>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="L201" class="LineNr">201 </span>  <span class="Normal">uint32_t</span>* handle = <a href='010---vm.cc.html#L224'>mem_addr_u32</a><span class="Delimiter">(</span>addr<span class="Delimiter">);</span>  <span class="Comment">// error messages get printed here</span>
+<span id="L202" class="LineNr">202 </span>  <span class="Identifier">return</span> handle ? *handle : <span class="Constant">0</span><span class="Delimiter">;</span>
+<span id="L203" class="LineNr">203 </span><span class="Delimiter">}</span>
+<span id="L204" class="LineNr">204 </span><span class="Normal">inline</span> <span class="Normal">int32_t</span> <a href='010---vm.cc.html#L204'>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="L205" class="LineNr">205 </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#L200'>read_mem_u32</a><span class="Delimiter">(</span>addr<span class="Delimiter">));</span>
+<span id="L206" class="LineNr">206 </span><span class="Delimiter">}</span>
+<span id="L207" class="LineNr">207 </span>
+<span id="L208" class="LineNr">208 </span><span class="Normal">inline</span> <span class="Normal">uint8_t</span>* <a href='010---vm.cc.html#L208'>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="L209" class="LineNr">209 </span>  <span class="Normal">uint8_t</span>* result = <span class="Constant">NULL</span><span class="Delimiter">;</span>
+<span id="L210" class="LineNr">210 </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#L157'>SIZE</a><span class="Delimiter">(</span><a href='010---vm.cc.html#L171'>Mem</a><span class="Delimiter">);</span>  ++i<span class="Delimiter">)</span> <span class="Delimiter">{</span>
+<span id="L211" class="LineNr">211 </span>    <span class="Normal">if</span> <span class="Delimiter">(</span><a href='010---vm.cc.html#L171'>Mem</a><span class="Delimiter">.</span>at<span class="Delimiter">(</span>i<span class="Delimiter">).</span><a href='010---vm.cc.html#L131'>match</a><span class="Delimiter">(</span>addr<span class="Delimiter">))</span> <span class="Delimiter">{</span>
+<span id="L212" class="LineNr">212 </span>      <span class="Normal">if</span> <span class="Delimiter">(</span>result<span class="Delimiter">)</span>
+<span id="L213" class="LineNr">213 </span>        <a href='003trace.cc.html#L210'>raise</a> &lt;&lt; <span class="Constant">&quot;address 0x&quot;</span> &lt;&lt; <a href='010---vm.cc.html#L403'>HEXWORD</a> &lt;&lt; addr &lt;&lt; <span class="Constant">&quot; is in two <a href='011run.cc.html#L100'>segments</a></span><span class="cSpecial">\n</span><span class="Constant">&quot;</span> &lt;&lt; end<span class="Delimiter">();</span>
+<span id="L214" class="LineNr">214 </span>      result = &amp;Mem<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="L215" class="LineNr">215 </span>    <span class="Delimiter">}</span>
+<span id="L216" class="LineNr">216 </span>  <span class="Delimiter">}</span>
+<span id="L217" class="LineNr">217 </span>  <span class="Normal">if</span> <span class="Delimiter">(</span>result == <span class="Constant">NULL</span><span class="Delimiter">)</span>
+<span id="L218" class="LineNr">218 </span>    <a href='003trace.cc.html#L210'>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#L403'>HEXWORD</a> &lt;&lt; addr &lt;&lt; <span class="cSpecial">'\n'</span> &lt;&lt; end<span class="Delimiter">();</span>
+<span id="L219" class="LineNr">219 </span>  <span class="Identifier">return</span> result<span class="Delimiter">;</span>
+<span id="L220" class="LineNr">220 </span><span class="Delimiter">}</span>
+<span id="L221" class="LineNr">221 </span><span class="Normal">inline</span> <span class="Normal">int8_t</span>* <a href='010---vm.cc.html#L221'>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="L222" class="LineNr">222 </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#L208'>mem_addr_u8</a><span class="Delimiter">(</span>addr<span class="Delimiter">));</span>
 <span id="L223" class="LineNr">223 </span><span class="Delimiter">}</span>
-<span id="L224" class="LineNr">224 </span>
-<span id="L225" class="LineNr">225 </span><span class="Normal">inline</span> <span class="Normal">void</span> <a href='010---vm.cc.html#L225'>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="L226" class="LineNr">226 </span>  <span class="Normal">uint8_t</span>* handle = <a href='010---vm.cc.html#L186'>mem_addr_u8</a><span class="Delimiter">(</span>addr<span class="Delimiter">);</span>
-<span id="L227" class="LineNr">227 </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="L228" class="LineNr">228 </span><span class="Delimiter">}</span>
-<span id="L229" class="LineNr">229 </span><span class="Normal">inline</span> <span class="Normal">void</span> <a href='010---vm.cc.html#L229'>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="L230" class="LineNr">230 </span>  <span class="Normal">int8_t</span>* handle = <a href='010---vm.cc.html#L199'>mem_addr_i8</a><span class="Delimiter">(</span>addr<span class="Delimiter">);</span>
-<span id="L231" class="LineNr">231 </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="L232" class="LineNr">232 </span><span class="Delimiter">}</span>
-<span id="L233" class="LineNr">233 </span><span class="Normal">inline</span> <span class="Normal">void</span> <a href='010---vm.cc.html#L233'>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="L234" class="LineNr">234 </span>  <span class="Normal">uint32_t</span>* handle = <a href='010---vm.cc.html#L202'>mem_addr_u32</a><span class="Delimiter">(</span>addr<span class="Delimiter">);</span>
-<span id="L235" class="LineNr">235 </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="L236" class="LineNr">236 </span><span class="Delimiter">}</span>
-<span id="L237" class="LineNr">237 </span><span class="Normal">inline</span> <span class="Normal">void</span> <a href='010---vm.cc.html#L237'>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="L238" class="LineNr">238 </span>  <span class="Normal">int32_t</span>* handle = <a href='010---vm.cc.html#L217'>mem_addr_i32</a><span class="Delimiter">(</span>addr<span class="Delimiter">);</span>
-<span id="L239" class="LineNr">239 </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="L240" class="LineNr">240 </span><span class="Delimiter">}</span>
-<span id="L241" class="LineNr">241 </span>
-<span id="L242" class="LineNr">242 </span><span class="Normal">inline</span> <span class="Normal">bool</span> <a href='010---vm.cc.html#L242'>already_allocated</a><span class="Delimiter">(</span><span class="Normal">uint32_t</span> addr<span class="Delimiter">)</span> <span class="Delimiter">{</span>
-<span id="L243" class="LineNr">243 </span>  <span class="Normal">bool</span> result =<span class="Constant"> false</span><span class="Delimiter">;</span>
-<span id="L244" class="LineNr">244 </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#L157'>SIZE</a><span class="Delimiter">(</span><a href='010---vm.cc.html#L149'>Mem</a><span class="Delimiter">);</span>  ++i<span class="Delimiter">)</span> <span class="Delimiter">{</span>
-<span id="L245" class="LineNr">245 </span>    <span class="Normal">if</span> <span class="Delimiter">(</span><a href='010---vm.cc.html#L149'>Mem</a><span class="Delimiter">.</span>at<span class="Delimiter">(</span>i<span class="Delimiter">).</span><a href='010---vm.cc.html#L109'>match</a><span class="Delimiter">(</span>addr<span class="Delimiter">))</span> <span class="Delimiter">{</span>
-<span id="L246" class="LineNr">246 </span>      <span class="Normal">if</span> <span class="Delimiter">(</span>result<span class="Delimiter">)</span>
-<span id="L247" class="LineNr">247 </span>        <a href='003trace.cc.html#L211'>raise</a> &lt;&lt; <span class="Constant">&quot;address 0x&quot;</span> &lt;&lt; <a href='010---vm.cc.html#L368'>HEXWORD</a> &lt;&lt; addr &lt;&lt; <span class="Constant">&quot; is in two <a href='011run.cc.html#L100'>segments</a></span><span class="cSpecial">\n</span><span class="Constant">&quot;</span> &lt;&lt; end<span class="Delimiter">();</span>
-<span id="L248" class="LineNr">248 </span>      result =<span class="Constant"> true</span><span class="Delimiter">;</span>
-<span id="L249" class="LineNr">249 </span>    <span class="Delimiter">}</span>
-<span id="L250" class="LineNr">250 </span>  <span class="Delimiter">}</span>
-<span id="L251" class="LineNr">251 </span>  <span class="Identifier">return</span> result<span class="Delimiter">;</span>
-<span id="L252" class="LineNr">252 </span><span class="Delimiter">}</span>
+<span id="L224" class="LineNr">224 </span><span class="Normal">inline</span> <span class="Normal">uint32_t</span>* <a href='010---vm.cc.html#L224'>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="L225" class="LineNr">225 </span>  <span class="Normal">uint32_t</span>* result = <span class="Constant">NULL</span><span class="Delimiter">;</span>
+<span id="L226" class="LineNr">226 </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#L157'>SIZE</a><span class="Delimiter">(</span><a href='010---vm.cc.html#L171'>Mem</a><span class="Delimiter">);</span>  ++i<span class="Delimiter">)</span> <span class="Delimiter">{</span>
+<span id="L227" class="LineNr">227 </span>    <span class="Normal">if</span> <span class="Delimiter">(</span><a href='010---vm.cc.html#L171'>Mem</a><span class="Delimiter">.</span>at<span class="Delimiter">(</span>i<span class="Delimiter">).</span><a href='010---vm.cc.html#L134'>match32</a><span class="Delimiter">(</span>addr<span class="Delimiter">))</span> <span class="Delimiter">{</span>
+<span id="L228" class="LineNr">228 </span>      <span class="Normal">if</span> <span class="Delimiter">(</span>result<span class="Delimiter">)</span>
+<span id="L229" class="LineNr">229 </span>        <a href='003trace.cc.html#L210'>raise</a> &lt;&lt; <span class="Constant">&quot;address 0x&quot;</span> &lt;&lt; <a href='010---vm.cc.html#L403'>HEXWORD</a> &lt;&lt; addr &lt;&lt; <span class="Constant">&quot; is in two <a href='011run.cc.html#L100'>segments</a></span><span class="cSpecial">\n</span><span class="Constant">&quot;</span> &lt;&lt; end<span class="Delimiter">();</span>
+<span id="L230" class="LineNr">230 </span>      result = <span class="Normal">reinterpret_cast</span>&lt;<span class="Normal">uint32_t</span>*&gt;<span class="Delimiter">(</span>&amp;Mem<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="L231" class="LineNr">231 </span>    <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">if</span> <span class="Delimiter">(</span>result == <span class="Constant">NULL</span><span class="Delimiter">)</span> <span class="Delimiter">{</span>
+<span id="L234" class="LineNr">234 </span>    <a href='003trace.cc.html#L210'>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#L403'>HEXWORD</a> &lt;&lt; addr &lt;&lt; <span class="cSpecial">'\n'</span> &lt;&lt; end<span class="Delimiter">();</span>
+<span id="L235" class="LineNr">235 </span>    <a href='003trace.cc.html#L210'>raise</a> &lt;&lt; <span class="Constant">&quot;The entire 4-byte <a href='011run.cc.html#L123'>word</a> should be initialized and lie in a single segment.</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span> &lt;&lt; end<span class="Delimiter">();</span>
+<span id="L236" class="LineNr">236 </span>  <span class="Delimiter">}</span>
+<span id="L237" class="LineNr">237 </span>  <span class="Identifier">return</span> result<span class="Delimiter">;</span>
+<span id="L238" class="LineNr">238 </span><span class="Delimiter">}</span>
+<span id="L239" class="LineNr">239 </span><span class="Normal">inline</span> <span class="Normal">int32_t</span>* <a href='010---vm.cc.html#L239'>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="L240" class="LineNr">240 </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#L224'>mem_addr_u32</a><span class="Delimiter">(</span>addr<span class="Delimiter">));</span>
+<span id="L241" class="LineNr">241 </span><span class="Delimiter">}</span>
+<span id="L242" class="LineNr">242 </span><span class="Comment">// helper for some syscalls. But read-only.</span>
+<span id="L243" class="LineNr">243 </span><span class="Normal">inline</span> <span class="Normal">const</span> <span class="Normal">char</span>* <a href='010---vm.cc.html#L243'>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="L244" class="LineNr">244 </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#L208'>mem_addr_u8</a><span class="Delimiter">(</span>addr<span class="Delimiter">));</span>
+<span id="L245" class="LineNr">245 </span><span class="Delimiter">}</span>
+<span id="L246" class="LineNr">246 </span><span class="Normal">inline</span> string <a href='010---vm.cc.html#L246'>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="L247" class="LineNr">247 </span>  ostringstream out<span class="Delimiter">;</span>
+<span id="L248" class="LineNr">248 </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="L249" class="LineNr">249 </span>    out &lt;&lt; <a href='010---vm.cc.html#L193'>read_mem_u8</a><span class="Delimiter">(</span>addr+i<span class="Delimiter">);</span>
+<span id="L250" class="LineNr">250 </span>  <span class="Identifier">return</span> out<span class="Delimiter">.</span>str<span class="Delimiter">();</span>
+<span id="L251" class="LineNr">251 </span><span class="Delimiter">}</span>
+<span id="L252" class="LineNr">252 </span>
 <span id="L253" class="LineNr">253 </span>
-<span id="L254" class="LineNr">254 </span><span class="SalientComment">//:: core interpreter loop</span>
-<span id="L255" class="LineNr">255 </span>
-<span id="L256" class="LineNr">256 </span><span class="Delimiter">:(code)</span>
-<span id="L257" class="LineNr">257 </span><span class="Comment">// skeleton of how x86 instructions are decoded</span>
-<span id="L258" class="LineNr">258 </span><span class="Normal">void</span> <a href='010---vm.cc.html#L258'>run_one_instruction</a><span class="Delimiter">()</span> <span class="Delimiter">{</span>
-<span id="L259" class="LineNr">259 </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="L260" class="LineNr">260 </span>  <a href='003trace.cc.html#L204'>trace</a><span class="Delimiter">(</span><span class="Constant">90</span><span class="Delimiter">,</span> <span class="Constant">&quot;run&quot;</span><span class="Delimiter">)</span> &lt;&lt; <span class="Constant">&quot;inst: 0x&quot;</span> &lt;&lt; <a href='010---vm.cc.html#L368'>HEXWORD</a> &lt;&lt; <a href='010---vm.cc.html#L29'>EIP</a> &lt;&lt; end<span class="Delimiter">();</span>
-<span id="L261" class="LineNr">261 </span><span class="CommentedCode">//?   dump_registers();</span>
-<span id="L262" class="LineNr">262 </span><span class="CommentedCode">//?   cerr &lt;&lt; &quot;inst: 0x&quot; &lt;&lt; EIP &lt;&lt; &quot; =&gt; &quot;;</span>
-<span id="L263" class="LineNr">263 </span>  op = <a href='010---vm.cc.html#L322'>next</a><span class="Delimiter">();</span>
-<span id="L264" class="LineNr">264 </span><span class="CommentedCode">//?   cerr &lt;&lt; HEXBYTE &lt;&lt; NUM(op) &lt;&lt; '\n';</span>
-<span id="L265" class="LineNr">265 </span>  <span class="Normal">switch</span> <span class="Delimiter">(</span>op<span class="Delimiter">)</span> <span class="Delimiter">{</span>
-<span id="L266" class="LineNr">266 </span>  <span class="Normal">case</span> <span class="Constant">0xf4</span>:  <span class="Comment">// hlt</span>
-<span id="L267" class="LineNr">267 </span>    <a href='010---vm.cc.html#L29'>EIP</a> = <a href='010---vm.cc.html#L163'>End_of_program</a><span class="Delimiter">;</span>
-<span id="L268" class="LineNr">268 </span>    <span class="Identifier">break</span><span class="Delimiter">;</span>
-<span id="L269" class="LineNr">269 </span>  <span class="Comment">// End Single-Byte Opcodes</span>
-<span id="L270" class="LineNr">270 </span>  <span class="Normal">case</span> <span class="Constant">0x0f</span>:
-<span id="L271" class="LineNr">271 </span>    <span class="Normal">switch</span><span class="Delimiter">(</span>op2 = <a href='010---vm.cc.html#L322'>next</a><span class="Delimiter">())</span> <span class="Delimiter">{</span>
-<span id="L272" class="LineNr">272 </span>    <span class="Comment">// End Two-Byte Opcodes Starting With 0f</span>
-<span id="L273" class="LineNr">273 </span>    <span class="Normal">default</span>:
-<span id="L274" class="LineNr">274 </span>      cerr &lt;&lt; <span class="Constant">&quot;unrecognized second opcode after 0f: &quot;</span> &lt;&lt; <a href='010---vm.cc.html#L367'>HEXBYTE</a> &lt;&lt; <a href='010---vm.cc.html#L370'>NUM</a><span class="Delimiter">(</span>op2<span class="Delimiter">)</span> &lt;&lt; <span class="cSpecial">'\n'</span><span class="Delimiter">;</span>
-<span id="L275" class="LineNr">275 </span>      <a href='003trace.cc.html#L208'>DUMP</a><span class="Delimiter">(</span><span class="Constant">&quot;&quot;</span><span class="Delimiter">);</span>
-<span id="L276" class="LineNr">276 </span>      exit<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">);</span>
-<span id="L277" class="LineNr">277 </span>    <span class="Delimiter">}</span>
-<span id="L278" class="LineNr">278 </span>    <span class="Identifier">break</span><span class="Delimiter">;</span>
-<span id="L279" class="LineNr">279 </span>  <span class="Normal">case</span> <span class="Constant">0xf2</span>:
-<span id="L280" class="LineNr">280 </span>    <span class="Normal">switch</span><span class="Delimiter">(</span>op2 = <a href='010---vm.cc.html#L322'>next</a><span class="Delimiter">())</span> <span class="Delimiter">{</span>
-<span id="L281" class="LineNr">281 </span>    <span class="Comment">// End Two-Byte Opcodes Starting With f2</span>
-<span id="L282" class="LineNr">282 </span>    <span class="Normal">case</span> <span class="Constant">0x0f</span>:
-<span id="L283" class="LineNr">283 </span>      <span class="Normal">switch</span><span class="Delimiter">(</span>op3 = <a href='010---vm.cc.html#L322'>next</a><span class="Delimiter">())</span> <span class="Delimiter">{</span>
-<span id="L284" class="LineNr">284 </span>      <span class="Comment">// End Three-Byte Opcodes Starting With f2 0f</span>
-<span id="L285" class="LineNr">285 </span>      <span class="Normal">default</span>:
-<span id="L286" class="LineNr">286 </span>        cerr &lt;&lt; <span class="Constant">&quot;unrecognized third opcode after f2 0f: &quot;</span> &lt;&lt; <a href='010---vm.cc.html#L367'>HEXBYTE</a> &lt;&lt; <a href='010---vm.cc.html#L370'>NUM</a><span class="Delimiter">(</span>op3<span class="Delimiter">)</span> &lt;&lt; <span class="cSpecial">'\n'</span><span class="Delimiter">;</span>
-<span id="L287" class="LineNr">287 </span>        <a href='003trace.cc.html#L208'>DUMP</a><span class="Delimiter">(</span><span class="Constant">&quot;&quot;</span><span class="Delimiter">);</span>
-<span id="L288" class="LineNr">288 </span>        exit<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">);</span>
-<span id="L289" class="LineNr">289 </span>      <span class="Delimiter">}</span>
-<span id="L290" class="LineNr">290 </span>      <span class="Identifier">break</span><span class="Delimiter">;</span>
-<span id="L291" class="LineNr">291 </span>    <span class="Normal">default</span>:
-<span id="L292" class="LineNr">292 </span>      cerr &lt;&lt; <span class="Constant">&quot;unrecognized second opcode after f2: &quot;</span> &lt;&lt; <a href='010---vm.cc.html#L367'>HEXBYTE</a> &lt;&lt; <a href='010---vm.cc.html#L370'>NUM</a><span class="Delimiter">(</span>op2<span class="Delimiter">)</span> &lt;&lt; <span class="cSpecial">'\n'</span><span class="Delimiter">;</span>
-<span id="L293" class="LineNr">293 </span>      <a href='003trace.cc.html#L208'>DUMP</a><span class="Delimiter">(</span><span class="Constant">&quot;&quot;</span><span class="Delimiter">);</span>
-<span id="L294" class="LineNr">294 </span>      exit<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">);</span>
-<span id="L295" class="LineNr">295 </span>    <span class="Delimiter">}</span>
-<span id="L296" class="LineNr">296 </span>    <span class="Identifier">break</span><span class="Delimiter">;</span>
-<span id="L297" class="LineNr">297 </span>  <span class="Normal">case</span> <span class="Constant">0xf3</span>:
-<span id="L298" class="LineNr">298 </span>    <span class="Normal">switch</span><span class="Delimiter">(</span>op2 = <a href='010---vm.cc.html#L322'>next</a><span class="Delimiter">())</span> <span class="Delimiter">{</span>
-<span id="L299" class="LineNr">299 </span>    <span class="Comment">// End Two-Byte Opcodes Starting With f3</span>
-<span id="L300" class="LineNr">300 </span>    <span class="Normal">case</span> <span class="Constant">0x0f</span>:
-<span id="L301" class="LineNr">301 </span>      <span class="Normal">switch</span><span class="Delimiter">(</span>op3 = <a href='010---vm.cc.html#L322'>next</a><span class="Delimiter">())</span> <span class="Delimiter">{</span>
-<span id="L302" class="LineNr">302 </span>      <span class="Comment">// End Three-Byte Opcodes Starting With f3 0f</span>
-<span id="L303" class="LineNr">303 </span>      <span class="Normal">default</span>:
-<span id="L304" class="LineNr">304 </span>        cerr &lt;&lt; <span class="Constant">&quot;unrecognized third opcode after f3 0f: &quot;</span> &lt;&lt; <a href='010---vm.cc.html#L367'>HEXBYTE</a> &lt;&lt; <a href='010---vm.cc.html#L370'>NUM</a><span class="Delimiter">(</span>op3<span class="Delimiter">)</span> &lt;&lt; <span class="cSpecial">'\n'</span><span class="Delimiter">;</span>
-<span id="L305" class="LineNr">305 </span>        <a href='003trace.cc.html#L208'>DUMP</a><span class="Delimiter">(</span><span class="Constant">&quot;&quot;</span><span class="Delimiter">);</span>
-<span id="L306" class="LineNr">306 </span>        exit<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">);</span>
-<span id="L307" class="LineNr">307 </span>      <span class="Delimiter">}</span>
-<span id="L308" class="LineNr">308 </span>      <span class="Identifier">break</span><span class="Delimiter">;</span>
-<span id="L309" class="LineNr">309 </span>    <span class="Normal">default</span>:
-<span id="L310" class="LineNr">310 </span>      cerr &lt;&lt; <span class="Constant">&quot;unrecognized second opcode after f3: &quot;</span> &lt;&lt; <a href='010---vm.cc.html#L367'>HEXBYTE</a> &lt;&lt; <a href='010---vm.cc.html#L370'>NUM</a><span class="Delimiter">(</span>op2<span class="Delimiter">)</span> &lt;&lt; <span class="cSpecial">'\n'</span><span class="Delimiter">;</span>
-<span id="L311" class="LineNr">311 </span>      <a href='003trace.cc.html#L208'>DUMP</a><span class="Delimiter">(</span><span class="Constant">&quot;&quot;</span><span class="Delimiter">);</span>
-<span id="L312" class="LineNr">312 </span>      exit<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">);</span>
-<span id="L313" class="LineNr">313 </span>    <span class="Delimiter">}</span>
-<span id="L314" class="LineNr">314 </span>    <span class="Identifier">break</span><span class="Delimiter">;</span>
-<span id="L315" class="LineNr">315 </span>  <span class="Normal">default</span>:
-<span id="L316" class="LineNr">316 </span>    cerr &lt;&lt; <span class="Constant">&quot;unrecognized opcode: &quot;</span> &lt;&lt; <a href='010---vm.cc.html#L367'>HEXBYTE</a> &lt;&lt; <a href='010---vm.cc.html#L370'>NUM</a><span class="Delimiter">(</span>op<span class="Delimiter">)</span> &lt;&lt; <span class="cSpecial">'\n'</span><span class="Delimiter">;</span>
-<span id="L317" class="LineNr">317 </span>    <a href='003trace.cc.html#L208'>DUMP</a><span class="Delimiter">(</span><span class="Constant">&quot;&quot;</span><span class="Delimiter">);</span>
-<span id="L318" class="LineNr">318 </span>    exit<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">);</span>
-<span id="L319" class="LineNr">319 </span>  <span class="Delimiter">}</span>
-<span id="L320" class="LineNr">320 </span><span class="Delimiter">}</span>
-<span id="L321" class="LineNr">321 </span>
-<span id="L322" class="LineNr">322 </span><span class="Normal">inline</span> <span class="Normal">uint8_t</span> <a href='010---vm.cc.html#L322'>next</a><span class="Delimiter">()</span> <span class="Delimiter">{</span>
-<span id="L323" class="LineNr">323 </span>  <span class="Identifier">return</span> <a href='010---vm.cc.html#L171'>read_mem_u8</a><span class="Delimiter">(</span>EIP++<span class="Delimiter">);</span>
-<span id="L324" class="LineNr">324 </span><span class="Delimiter">}</span>
-<span id="L325" class="LineNr">325 </span>
-<span id="L326" class="LineNr">326 </span><span class="Normal">void</span> <a href='010---vm.cc.html#L326'>dump_registers</a><span class="Delimiter">()</span> <span class="Delimiter">{</span>
-<span id="L327" class="LineNr">327 </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="L328" class="LineNr">328 </span>    <span class="Normal">if</span> <span class="Delimiter">(</span>i &gt; <span class="Constant">0</span><span class="Delimiter">)</span> cerr &lt;&lt; <span class="Constant">&quot;; &quot;</span><span class="Delimiter">;</span>
-<span id="L329" class="LineNr">329 </span>    cerr &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; Reg[i]<span class="Delimiter">.</span>u<span class="Delimiter">;</span>
-<span id="L330" class="LineNr">330 </span>  <span class="Delimiter">}</span>
-<span id="L331" class="LineNr">331 </span>  cerr &lt;&lt; <span class="Constant">&quot; -- SF: &quot;</span> &lt;&lt; SF &lt;&lt; <span class="Constant">&quot;; ZF: &quot;</span> &lt;&lt; ZF &lt;&lt; <span class="Constant">&quot;; <a href='010---vm.cc.html#L59'>OF</a>: &quot;</span> &lt;&lt; <a href='010---vm.cc.html#L59'>OF</a> &lt;&lt; <span class="cSpecial">'\n'</span><span class="Delimiter">;</span>
-<span id="L332" class="LineNr">332 </span><span class="Delimiter">}</span>
-<span id="L333" class="LineNr">333 </span>
-<span id="L334" class="LineNr">334 </span><span class="Comment">//: start tracking supported opcodes</span>
-<span id="L335" class="LineNr">335 </span><span class="Delimiter">:(before &quot;End Globals&quot;)</span>
-<span id="L336" class="LineNr">336 </span>map&lt;<span class="Comment">/*</span><span class="Comment">op</span><span class="Comment">*/</span>string<span class="Delimiter">,</span> string&gt; <a href='010---vm.cc.html#L336'>name</a><span class="Delimiter">;</span>
-<span id="L337" class="LineNr">337 </span>map&lt;<span class="Comment">/*</span><span class="Comment">op</span><span class="Comment">*/</span>string<span class="Delimiter">,</span> string&gt; <a href='010---vm.cc.html#L337'>name_0f</a><span class="Delimiter">;</span>
-<span id="L338" class="LineNr">338 </span>map&lt;<span class="Comment">/*</span><span class="Comment">op</span><span class="Comment">*/</span>string<span class="Delimiter">,</span> string&gt; <a href='010---vm.cc.html#L338'>name_f3</a><span class="Delimiter">;</span>
-<span id="L339" class="LineNr">339 </span>map&lt;<span class="Comment">/*</span><span class="Comment">op</span><span class="Comment">*/</span>string<span class="Delimiter">,</span> string&gt; <a href='010---vm.cc.html#L339'>name_f3_0f</a><span class="Delimiter">;</span>
-<span id="L340" class="LineNr">340 </span><span class="Delimiter">:(before &quot;End One-time Setup&quot;)</span>
-<span id="L341" class="LineNr">341 </span><a href='010---vm.cc.html#L343'>init_op_names</a><span class="Delimiter">();</span>
-<span id="L342" class="LineNr">342 </span><span class="Delimiter">:(code)</span>
-<span id="L343" class="LineNr">343 </span><span class="Normal">void</span> <a href='010---vm.cc.html#L343'>init_op_names</a><span class="Delimiter">()</span> <span class="Delimiter">{</span>
-<span id="L344" class="LineNr">344 </span>  <a href='001help.cc.html#L243'>put</a><span class="Delimiter">(</span><a href='010---vm.cc.html#L336'>name</a><span class="Delimiter">,</span> <span class="Constant">&quot;f4&quot;</span><span class="Delimiter">,</span> <span class="Constant">&quot;halt&quot;</span><span class="Delimiter">);</span>
-<span id="L345" class="LineNr">345 </span>  <span class="Comment">// End Initialize Op Names(name)</span>
-<span id="L346" class="LineNr">346 </span><span class="Delimiter">}</span>
-<span id="L347" class="LineNr">347 </span>
-<span id="L348" class="LineNr">348 </span><span class="Delimiter">:(before &quot;End <a href='001help.cc.html#L53'>Help</a> Special-cases(key)&quot;)</span>
-<span id="L349" class="LineNr">349 </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="L350" class="LineNr">350 </span>  cerr &lt;&lt; <span class="Constant">&quot;Opcodes currently supported by SubX:</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span><span class="Delimiter">;</span>
-<span id="L351" class="LineNr">351 </span>  <span class="Normal">for</span> <span class="Delimiter">(</span>map&lt;string<span class="Delimiter">,</span> string&gt;::iterator p = <a href='010---vm.cc.html#L336'>name</a><span class="Delimiter">.</span>begin<span class="Delimiter">();</span>  p != <a href='010---vm.cc.html#L336'>name</a><span class="Delimiter">.</span>end<span class="Delimiter">();</span>  ++p<span class="Delimiter">)</span>
-<span id="L352" class="LineNr">352 </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="L353" class="LineNr">353 </span>  <span class="Normal">for</span> <span class="Delimiter">(</span>map&lt;string<span class="Delimiter">,</span> string&gt;::iterator p = <a href='010---vm.cc.html#L337'>name_0f</a><span class="Delimiter">.</span>begin<span class="Delimiter">();</span>  p != <a href='010---vm.cc.html#L337'>name_0f</a><span class="Delimiter">.</span>end<span class="Delimiter">();</span>  ++p<span class="Delimiter">)</span>
-<span id="L354" class="LineNr">354 </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="L355" class="LineNr">355 </span>  <span class="Normal">for</span> <span class="Delimiter">(</span>map&lt;string<span class="Delimiter">,</span> string&gt;::iterator p = <a href='010---vm.cc.html#L338'>name_f3</a><span class="Delimiter">.</span>begin<span class="Delimiter">();</span>  p != <a href='010---vm.cc.html#L338'>name_f3</a><span class="Delimiter">.</span>end<span class="Delimiter">();</span>  ++p<span class="Delimiter">)</span>
-<span id="L356" class="LineNr">356 </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="L357" class="LineNr">357 </span>  <span class="Normal">for</span> <span class="Delimiter">(</span>map&lt;string<span class="Delimiter">,</span> string&gt;::iterator p = <a href='010---vm.cc.html#L339'>name_f3_0f</a><span class="Delimiter">.</span>begin<span class="Delimiter">();</span>  p != <a href='010---vm.cc.html#L339'>name_f3_0f</a><span class="Delimiter">.</span>end<span class="Delimiter">();</span>  ++p<span class="Delimiter">)</span>
-<span id="L358" class="LineNr">358 </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="L359" class="LineNr">359 </span>  cerr &lt;&lt; <span class="Constant">&quot;Run `subx help instructions` for details on <a href='011run.cc.html#L118'>words</a> like 'r32' and 'disp8'.</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span><span class="Delimiter">;</span>
-<span id="L360" class="LineNr">360 </span>  <span class="Identifier">return</span> <span class="Constant">0</span><span class="Delimiter">;</span>
-<span id="L361" class="LineNr">361 </span><span class="Delimiter">}</span>
-<span id="L362" class="LineNr">362 </span><span class="Delimiter">:(before &quot;End <a href='001help.cc.html#L53'>Help</a> Contents&quot;)</span>
-<span id="L363" class="LineNr">363 </span>cerr &lt;&lt; <span class="Constant">&quot;  opcodes</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span><span class="Delimiter">;</span>
-<span id="L364" class="LineNr">364 </span>
-<span id="L365" class="LineNr">365 </span><span class="Delimiter">:(before &quot;End Includes&quot;)</span>
-<span id="L366" class="LineNr">366 </span><span class="Comment">#include &lt;iomanip&gt;</span>
-<span id="L367" class="LineNr">367 </span><span class="Comment">#define HEXBYTE  std::hex &lt;&lt; std::setw(2) &lt;&lt; std::setfill('0')</span>
-<span id="L368" class="LineNr">368 </span><span class="Comment">#define HEXWORD  std::hex &lt;&lt; std::setw(8) &lt;&lt; std::setfill('0')</span>
-<span id="L369" class="LineNr">369 </span><span class="Comment">// ugly that iostream doesn't print uint8_t as an integer</span>
-<span id="L370" class="LineNr">370 </span><span class="Comment">#define NUM(X) static_cast&lt;int&gt;(X)</span>
-<span id="L371" class="LineNr">371 </span><span class="Comment">#include &lt;stdint.h&gt;</span>
+<span id="L254" class="LineNr">254 </span><span class="Normal">inline</span> <span class="Normal">void</span> <a href='010---vm.cc.html#L254'>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="L255" class="LineNr">255 </span>  <span class="Normal">uint8_t</span>* handle = <a href='010---vm.cc.html#L208'>mem_addr_u8</a><span class="Delimiter">(</span>addr<span class="Delimiter">);</span>
+<span id="L256" class="LineNr">256 </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="L257" class="LineNr">257 </span><span class="Delimiter">}</span>
+<span id="L258" class="LineNr">258 </span><span class="Normal">inline</span> <span class="Normal">void</span> <a href='010---vm.cc.html#L258'>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="L259" class="LineNr">259 </span>  <span class="Normal">int8_t</span>* handle = <a href='010---vm.cc.html#L221'>mem_addr_i8</a><span class="Delimiter">(</span>addr<span class="Delimiter">);</span>
+<span id="L260" class="LineNr">260 </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="L261" class="LineNr">261 </span><span class="Delimiter">}</span>
+<span id="L262" class="LineNr">262 </span><span class="Normal">inline</span> <span class="Normal">void</span> <a href='010---vm.cc.html#L262'>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="L263" class="LineNr">263 </span>  <span class="Normal">uint32_t</span>* handle = <a href='010---vm.cc.html#L224'>mem_addr_u32</a><span class="Delimiter">(</span>addr<span class="Delimiter">);</span>
+<span id="L264" class="LineNr">264 </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="L265" class="LineNr">265 </span><span class="Delimiter">}</span>
+<span id="L266" class="LineNr">266 </span><span class="Normal">inline</span> <span class="Normal">void</span> <a href='010---vm.cc.html#L266'>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="L267" class="LineNr">267 </span>  <span class="Normal">int32_t</span>* handle = <a href='010---vm.cc.html#L239'>mem_addr_i32</a><span class="Delimiter">(</span>addr<span class="Delimiter">);</span>
+<span id="L268" class="LineNr">268 </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="L269" class="LineNr">269 </span><span class="Delimiter">}</span>
+<span id="L270" class="LineNr">270 </span>
+<span id="L271" class="LineNr">271 </span><span class="Normal">inline</span> <span class="Normal">bool</span> <a href='010---vm.cc.html#L271'>already_allocated</a><span class="Delimiter">(</span><span class="Normal">uint32_t</span> addr<span class="Delimiter">)</span> <span class="Delimiter">{</span>
+<span id="L272" class="LineNr">272 </span>  <span class="Normal">bool</span> result =<span class="Constant"> false</span><span class="Delimiter">;</span>
+<span id="L273" class="LineNr">273 </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#L157'>SIZE</a><span class="Delimiter">(</span><a href='010---vm.cc.html#L171'>Mem</a><span class="Delimiter">);</span>  ++i<span class="Delimiter">)</span> <span class="Delimiter">{</span>
+<span id="L274" class="LineNr">274 </span>    <span class="Normal">if</span> <span class="Delimiter">(</span><a href='010---vm.cc.html#L171'>Mem</a><span class="Delimiter">.</span>at<span class="Delimiter">(</span>i<span class="Delimiter">).</span><a href='010---vm.cc.html#L131'>match</a><span class="Delimiter">(</span>addr<span class="Delimiter">))</span> <span class="Delimiter">{</span>
+<span id="L275" class="LineNr">275 </span>      <span class="Normal">if</span> <span class="Delimiter">(</span>result<span class="Delimiter">)</span>
+<span id="L276" class="LineNr">276 </span>        <a href='003trace.cc.html#L210'>raise</a> &lt;&lt; <span class="Constant">&quot;address 0x&quot;</span> &lt;&lt; <a href='010---vm.cc.html#L403'>HEXWORD</a> &lt;&lt; addr &lt;&lt; <span class="Constant">&quot; is in two <a href='011run.cc.html#L100'>segments</a></span><span class="cSpecial">\n</span><span class="Constant">&quot;</span> &lt;&lt; end<span class="Delimiter">();</span>
+<span id="L277" class="LineNr">277 </span>      result =<span class="Constant"> true</span><span class="Delimiter">;</span>
+<span id="L278" class="LineNr">278 </span>    <span class="Delimiter">}</span>
+<span id="L279" class="LineNr">279 </span>  <span class="Delimiter">}</span>
+<span id="L280" class="LineNr">280 </span>  <span class="Identifier">return</span> result<span class="Delimiter">;</span>
+<span id="L281" class="LineNr">281 </span><span class="Delimiter">}</span>
+<span id="L282" class="LineNr">282 </span>
+<span id="L283" class="LineNr">283 </span><span class="SalientComment">//:: core interpreter loop</span>
+<span id="L284" class="LineNr">284 </span>
+<span id="L285" class="LineNr">285 </span><span class="Delimiter">:(code)</span>
+<span id="L286" class="LineNr">286 </span><span class="Comment">// skeleton of how x86 instructions are decoded</span>
+<span id="L287" class="LineNr">287 </span><span class="Normal">void</span> <a href='010---vm.cc.html#L287'>run_one_instruction</a><span class="Delimiter">()</span> <span class="Delimiter">{</span>
+<span id="L288" class="LineNr">288 </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="L289" class="LineNr">289 </span>  <span class="Comment">// Run One Instruction</span>
+<span id="L290" class="LineNr">290 </span>  <a href='003trace.cc.html#L203'>trace</a><span class="Delimiter">(</span><span class="Constant">90</span><span class="Delimiter">,</span> <span class="Constant">&quot;run&quot;</span><span class="Delimiter">)</span> &lt;&lt; <span class="Constant">&quot;inst: 0x&quot;</span> &lt;&lt; <a href='010---vm.cc.html#L403'>HEXWORD</a> &lt;&lt; <a href='010---vm.cc.html#L29'>EIP</a> &lt;&lt; end<span class="Delimiter">();</span>
+<span id="L291" class="LineNr">291 </span>  op = <a href='010---vm.cc.html#L354'>next</a><span class="Delimiter">();</span>
+<span id="L292" class="LineNr">292 </span>  <span class="Normal">if</span> <span class="Delimiter">(</span><a href='003trace.cc.html#L188'>Dump_trace</a><span class="Delimiter">)</span> <span class="Delimiter">{</span>
+<span id="L293" class="LineNr">293 </span>    cerr &lt;&lt; <span class="Constant">&quot;opcode: &quot;</span> &lt;&lt; <a href='010---vm.cc.html#L402'>HEXBYTE</a> &lt;&lt; <a href='010---vm.cc.html#L405'>NUM</a><span class="Delimiter">(</span>op<span class="Delimiter">)</span> &lt;&lt; <span class="cSpecial">'\n'</span><span class="Delimiter">;</span>
+<span id="L294" class="LineNr">294 </span>    cerr &lt;&lt; <span class="Constant">&quot;registers at start: &quot;</span><span class="Delimiter">;</span>
+<span id="L295" class="LineNr">295 </span>    <a href='010---vm.cc.html#L358'>dump_registers</a><span class="Delimiter">();</span>
+<span id="L296" class="LineNr">296 </span>  <span class="Delimiter">}</span>
+<span id="L297" class="LineNr">297 </span>  <span class="Normal">switch</span> <span class="Delimiter">(</span>op<span class="Delimiter">)</span> <span class="Delimiter">{</span>
+<span id="L298" class="LineNr">298 </span>  <span class="Normal">case</span> <span class="Constant">0xf4</span>:  <span class="Comment">// hlt</span>
+<span id="L299" class="LineNr">299 </span>    <a href='010---vm.cc.html#L29'>EIP</a> = <a href='010---vm.cc.html#L185'>End_of_program</a><span class="Delimiter">;</span>
+<span id="L300" class="LineNr">300 </span>    <span class="Identifier">break</span><span class="Delimiter">;</span>
+<span id="L301" class="LineNr">301 </span>  <span class="Comment">// End Single-Byte Opcodes</span>
+<span id="L302" class="LineNr">302 </span>  <span class="Normal">case</span> <span class="Constant">0x0f</span>:
+<span id="L303" class="LineNr">303 </span>    <span class="Normal">switch</span><span class="Delimiter">(</span>op2 = <a href='010---vm.cc.html#L354'>next</a><span class="Delimiter">())</span> <span class="Delimiter">{</span>
+<span id="L304" class="LineNr">304 </span>    <span class="Comment">// End Two-Byte Opcodes Starting With 0f</span>
+<span id="L305" class="LineNr">305 </span>    <span class="Normal">default</span>:
+<span id="L306" class="LineNr">306 </span>      cerr &lt;&lt; <span class="Constant">&quot;unrecognized second opcode after 0f: &quot;</span> &lt;&lt; <a href='010---vm.cc.html#L402'>HEXBYTE</a> &lt;&lt; <a href='010---vm.cc.html#L405'>NUM</a><span class="Delimiter">(</span>op2<span class="Delimiter">)</span> &lt;&lt; <span class="cSpecial">'\n'</span><span class="Delimiter">;</span>
+<span id="L307" class="LineNr">307 </span>      <a href='003trace.cc.html#L207'>DUMP</a><span class="Delimiter">(</span><span class="Constant">&quot;&quot;</span><span class="Delimiter">);</span>
+<span id="L308" class="LineNr">308 </span>      exit<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">);</span>
+<span id="L309" class="LineNr">309 </span>    <span class="Delimiter">}</span>
+<span id="L310" class="LineNr">310 </span>    <span class="Identifier">break</span><span class="Delimiter">;</span>
+<span id="L311" class="LineNr">311 </span>  <span class="Normal">case</span> <span class="Constant">0xf2</span>:
+<span id="L312" class="LineNr">312 </span>    <span class="Normal">switch</span><span class="Delimiter">(</span>op2 = <a href='010---vm.cc.html#L354'>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 f2</span>
+<span id="L314" class="LineNr">314 </span>    <span class="Normal">case</span> <span class="Constant">0x0f</span>:
+<span id="L315" class="LineNr">315 </span>      <span class="Normal">switch</span><span class="Delimiter">(</span>op3 = <a href='010---vm.cc.html#L354'>next</a><span class="Delimiter">())</span> <span class="Delimiter">{</span>
+<span id="L316" class="LineNr">316 </span>      <span class="Comment">// End Three-Byte Opcodes Starting With f2 0f</span>
+<span id="L317" class="LineNr">317 </span>      <span class="Normal">default</span>:
+<span id="L318" class="LineNr">318 </span>        cerr &lt;&lt; <span class="Constant">&quot;unrecognized third opcode after f2 0f: &quot;</span> &lt;&lt; <a href='010---vm.cc.html#L402'>HEXBYTE</a> &lt;&lt; <a href='010---vm.cc.html#L405'>NUM</a><span class="Delimiter">(</span>op3<span class="Delimiter">)</span> &lt;&lt; <span class="cSpecial">'\n'</span><span class="Delimiter">;</span>
+<span id="L319" class="LineNr">319 </span>        <a href='003trace.cc.html#L207'>DUMP</a><span class="Delimiter">(</span><span class="Constant">&quot;&quot;</span><span class="Delimiter">);</span>
+<span id="L320" class="LineNr">320 </span>        exit<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">);</span>
+<span id="L321" class="LineNr">321 </span>      <span class="Delimiter">}</span>
+<span id="L322" class="LineNr">322 </span>      <span class="Identifier">break</span><span class="Delimiter">;</span>
+<span id="L323" class="LineNr">323 </span>    <span class="Normal">default</span>:
+<span id="L324" class="LineNr">324 </span>      cerr &lt;&lt; <span class="Constant">&quot;unrecognized second opcode after f2: &quot;</span> &lt;&lt; <a href='010---vm.cc.html#L402'>HEXBYTE</a> &lt;&lt; <a href='010---vm.cc.html#L405'>NUM</a><span class="Delimiter">(</span>op2<span class="Delimiter">)</span> &lt;&lt; <span class="cSpecial">'\n'</span><span class="Delimiter">;</span>
+<span id="L325" class="LineNr">325 </span>      <a href='003trace.cc.html#L207'>DUMP</a><span class="Delimiter">(</span><span class="Constant">&quot;&quot;</span><span class="Delimiter">);</span>
+<span id="L326" class="LineNr">326 </span>      exit<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">);</span>
+<span id="L327" class="LineNr">327 </span>    <span class="Delimiter">}</span>
+<span id="L328" class="LineNr">328 </span>    <span class="Identifier">break</span><span class="Delimiter">;</span>
+<span id="L329" class="LineNr">329 </span>  <span class="Normal">case</span> <span class="Constant">0xf3</span>:
+<span id="L330" class="LineNr">330 </span>    <span class="Normal">switch</span><span class="Delimiter">(</span>op2 = <a href='010---vm.cc.html#L354'>next</a><span class="Delimiter">())</span> <span class="Delimiter">{</span>
+<span id="L331" class="LineNr">331 </span>    <span class="Comment">// End Two-Byte Opcodes Starting With f3</span>
+<span id="L332" class="LineNr">332 </span>    <span class="Normal">case</span> <span class="Constant">0x0f</span>:
+<span id="L333" class="LineNr">333 </span>      <span class="Normal">switch</span><span class="Delimiter">(</span>op3 = <a href='010---vm.cc.html#L354'>next</a><span class="Delimiter">())</span> <span class="Delimiter">{</span>
+<span id="L334" class="LineNr">334 </span>      <span class="Comment">// End Three-Byte Opcodes Starting With f3 0f</span>
+<span id="L335" class="LineNr">335 </span>      <span class="Normal">default</span>:
+<span id="L336" class="LineNr">336 </span>        cerr &lt;&lt; <span class="Constant">&quot;unrecognized third opcode after f3 0f: &quot;</span> &lt;&lt; <a href='010---vm.cc.html#L402'>HEXBYTE</a> &lt;&lt; <a href='010---vm.cc.html#L405'>NUM</a><span class="Delimiter">(</span>op3<span class="Delimiter">)</span> &lt;&lt; <span class="cSpecial">'\n'</span><span class="Delimiter">;</span>
+<span id="L337" class="LineNr">337 </span>        <a href='003trace.cc.html#L207'>DUMP</a><span class="Delimiter">(</span><span class="Constant">&quot;&quot;</span><span class="Delimiter">);</span>
+<span id="L338" class="LineNr">338 </span>        exit<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">);</span>
+<span id="L339" class="LineNr">339 </span>      <span class="Delimiter">}</span>
+<span id="L340" class="LineNr">340 </span>      <span class="Identifier">break</span><span class="Delimiter">;</span>
+<span id="L341" class="LineNr">341 </span>    <span class="Normal">default</span>:
+<span id="L342" class="LineNr">342 </span>      cerr &lt;&lt; <span class="Constant">&quot;unrecognized second opcode after f3: &quot;</span> &lt;&lt; <a href='010---vm.cc.html#L402'>HEXBYTE</a> &lt;&lt; <a href='010---vm.cc.html#L405'>NUM</a><span class="Delimiter">(</span>op2<span class="Delimiter">)</span> &lt;&lt; <span class="cSpecial">'\n'</span><span class="Delimiter">;</span>
+<span id="L343" class="LineNr">343 </span>      <a href='003trace.cc.html#L207'>DUMP</a><span class="Delimiter">(</span><span class="Constant">&quot;&quot;</span><span class="Delimiter">);</span>
+<span id="L344" class="LineNr">344 </span>      exit<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">);</span>
+<span id="L345" class="LineNr">345 </span>    <span class="Delimiter">}</span>
+<span id="L346" class="LineNr">346 </span>    <span class="Identifier">break</span><span class="Delimiter">;</span>
+<span id="L347" class="LineNr">347 </span>  <span class="Normal">default</span>:
+<span id="L348" class="LineNr">348 </span>    cerr &lt;&lt; <span class="Constant">&quot;unrecognized opcode: &quot;</span> &lt;&lt; <a href='010---vm.cc.html#L402'>HEXBYTE</a> &lt;&lt; <a href='010---vm.cc.html#L405'>NUM</a><span class="Delimiter">(</span>op<span class="Delimiter">)</span> &lt;&lt; <span class="cSpecial">'\n'</span><span class="Delimiter">;</span>
+<span id="L349" class="LineNr">349 </span>    <a href='003trace.cc.html#L207'>DUMP</a><span class="Delimiter">(</span><span class="Constant">&quot;&quot;</span><span class="Delimiter">);</span>
+<span id="L350" class="LineNr">350 </span>    exit<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">);</span>
+<span id="L351" class="LineNr">351 </span>  <span class="Delimiter">}</span>
+<span id="L352" class="LineNr">352 </span><span class="Delimiter">}</span>
+<span id="L353" class="LineNr">353 </span>
+<span id="L354" class="LineNr">354 </span><span class="Normal">inline</span> <span class="Normal">uint8_t</span> <a href='010---vm.cc.html#L354'>next</a><span class="Delimiter">()</span> <span class="Delimiter">{</span>
+<span id="L355" class="LineNr">355 </span>  <span class="Identifier">return</span> <a href='010---vm.cc.html#L193'>read_mem_u8</a><span class="Delimiter">(</span>EIP++<span class="Delimiter">);</span>
+<span id="L356" class="LineNr">356 </span><span class="Delimiter">}</span>
+<span id="L357" class="LineNr">357 </span>
+<span id="L358" class="LineNr">358 </span><span class="Normal">void</span> <a href='010---vm.cc.html#L358'>dump_registers</a><span class="Delimiter">()</span> <span class="Delimiter">{</span>
+<span id="L359" class="LineNr">359 </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="L360" class="LineNr">360 </span>    <span class="Normal">if</span> <span class="Delimiter">(</span>i &gt; <span class="Constant">0</span><span class="Delimiter">)</span> cerr &lt;&lt; <span class="Constant">&quot;; &quot;</span><span class="Delimiter">;</span>
+<span id="L361" class="LineNr">361 </span>    cerr &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; Reg[i]<span class="Delimiter">.</span>u<span class="Delimiter">;</span>
+<span id="L362" class="LineNr">362 </span>  <span class="Delimiter">}</span>
+<span id="L363" class="LineNr">363 </span>  cerr &lt;&lt; <span class="Constant">&quot; -- SF: &quot;</span> &lt;&lt; SF &lt;&lt; <span class="Constant">&quot;; ZF: &quot;</span> &lt;&lt; ZF &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> &lt;&lt; <span class="cSpecial">'\n'</span><span class="Delimiter">;</span>
+<span id="L364" class="LineNr">364 </span><span class="Delimiter">}</span>
+<span id="L365" class="LineNr">365 </span>
+<span id="L366" class="LineNr">366 </span><span class="Comment">//: start tracking supported opcodes</span>
+<span id="L367" class="LineNr">367 </span><span class="Delimiter">:(before &quot;End Globals&quot;)</span>
+<span id="L368" class="LineNr">368 </span>map&lt;<span class="Comment">/*</span><span class="Comment">op</span><span class="Comment">*/</span>string<span class="Delimiter">,</span> string&gt; <a href='010---vm.cc.html#L368'>Name</a><span class="Delimiter">;</span>
+<span id="L369" class="LineNr">369 </span>map&lt;<span class="Comment">/*</span><span class="Comment">op</span><span class="Comment">*/</span>string<span class="Delimiter">,</span> string&gt; <a href='010---vm.cc.html#L369'>Name_0f</a><span class="Delimiter">;</span>
+<span id="L370" class="LineNr">370 </span>map&lt;<span class="Comment">/*</span><span class="Comment">op</span><span class="Comment">*/</span>string<span class="Delimiter">,</span> string&gt; <a href='010---vm.cc.html#L370'>Name_f3</a><span class="Delimiter">;</span>
+<span id="L371" class="LineNr">371 </span>map&lt;<span class="Comment">/*</span><span class="Comment">op</span><span class="Comment">*/</span>string<span class="Delimiter">,</span> string&gt; <a href='010---vm.cc.html#L371'>Name_f3_0f</a><span class="Delimiter">;</span>
+<span id="L372" class="LineNr">372 </span><span class="Delimiter">:(before &quot;End One-time Setup&quot;)</span>
+<span id="L373" class="LineNr">373 </span><a href='010---vm.cc.html#L375'>init_op_names</a><span class="Delimiter">();</span>
+<span id="L374" class="LineNr">374 </span><span class="Delimiter">:(code)</span>
+<span id="L375" class="LineNr">375 </span><span class="Normal">void</span> <a href='010---vm.cc.html#L375'>init_op_names</a><span class="Delimiter">()</span> <span class="Delimiter">{</span>
+<span id="L376" class="LineNr">376 </span>  <a href='001help.cc.html#L243'>put</a><span class="Delimiter">(</span><a href='010---vm.cc.html#L368'>Name</a><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="L377" class="LineNr">377 </span>  <span class="Comment">// End Initialize Op Names</span>
+<span id="L378" class="LineNr">378 </span><span class="Delimiter">}</span>
+<span id="L379" class="LineNr">379 </span>
+<span id="L380" class="LineNr">380 </span><span class="Delimiter">:(before &quot;End <a href='001help.cc.html#L53'>Help</a> Special-cases(key)&quot;)</span>
+<span id="L381" class="LineNr">381 </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="L382" class="LineNr">382 </span>  cerr &lt;&lt; <span class="Constant">&quot;Opcodes currently supported by SubX:</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span><span class="Delimiter">;</span>
+<span id="L383" class="LineNr">383 </span>  <span class="Normal">for</span> <span class="Delimiter">(</span>map&lt;string<span class="Delimiter">,</span> string&gt;::iterator p = <a href='010---vm.cc.html#L368'>Name</a><span class="Delimiter">.</span>begin<span class="Delimiter">();</span>  p != <a href='010---vm.cc.html#L368'>Name</a><span class="Delimiter">.</span>end<span class="Delimiter">();</span>  ++p<span class="Delimiter">)</span>
+<span id="L384" class="LineNr">384 </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="L385" class="LineNr">385 </span>  <span class="Normal">for</span> <span class="Delimiter">(</span>map&lt;string<span class="Delimiter">,</span> string&gt;::iterator p = <a href='010---vm.cc.html#L369'>Name_0f</a><span class="Delimiter">.</span>begin<span class="Delimiter">();</span>  p != <a href='010---vm.cc.html#L369'>Name_0f</a><span class="Delimiter">.</span>end<span class="Delimiter">();</span>  ++p<span class="Delimiter">)</span>
+<span id="L386" class="LineNr">386 </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="L387" class="LineNr">387 </span>  <span class="Normal">for</span> <span class="Delimiter">(</span>map&lt;string<span class="Delimiter">,</span> string&gt;::iterator p = <a href='010---vm.cc.html#L370'>Name_f3</a><span class="Delimiter">.</span>begin<span class="Delimiter">();</span>  p != <a href='010---vm.cc.html#L370'>Name_f3</a><span class="Delimiter">.</span>end<span class="Delimiter">();</span>  ++p<span class="Delimiter">)</span>
+<span id="L388" class="LineNr">388 </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="L389" class="LineNr">389 </span>  <span class="Normal">for</span> <span class="Delimiter">(</span>map&lt;string<span class="Delimiter">,</span> string&gt;::iterator p = <a href='010---vm.cc.html#L371'>Name_f3_0f</a><span class="Delimiter">.</span>begin<span class="Delimiter">();</span>  p != <a href='010---vm.cc.html#L371'>Name_f3_0f</a><span class="Delimiter">.</span>end<span class="Delimiter">();</span>  ++p<span class="Delimiter">)</span>
+<span id="L390" class="LineNr">390 </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="L391" class="LineNr">391 </span>  cerr &lt;&lt; <span class="Constant">&quot;Run `subx help instructions` for details on <a href='011run.cc.html#L118'>words</a> like 'r32' and 'disp8'.</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
+<span id="L392" class="LineNr">392 </span>          <span class="Constant">&quot;For complete details on these instructions, consult the IA-32 manual (volume 2).</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
+<span id="L393" class="LineNr">393 </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>.</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span>
+<span id="L394" class="LineNr">394 </span>          <span class="Constant">&quot;The mnemonics in brackets will help you locate each instruction.</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span><span class="Delimiter">;</span>
+<span id="L395" class="LineNr">395 </span>  <span class="Identifier">return</span> <span class="Constant">0</span><span class="Delimiter">;</span>
+<span id="L396" class="LineNr">396 </span><span class="Delimiter">}</span>
+<span id="L397" class="LineNr">397 </span><span class="Delimiter">:(before &quot;End <a href='001help.cc.html#L53'>Help</a> Contents&quot;)</span>
+<span id="L398" class="LineNr">398 </span>cerr &lt;&lt; <span class="Constant">&quot;  opcodes</span><span class="cSpecial">\n</span><span class="Constant">&quot;</span><span class="Delimiter">;</span>
+<span id="L399" class="LineNr">399 </span>
+<span id="L400" class="LineNr">400 </span><span class="Delimiter">:(before &quot;End Includes&quot;)</span>
+<span id="L401" class="LineNr">401 </span><span class="Comment">#include &lt;iomanip&gt;</span>
+<span id="L402" class="LineNr">402 </span><span class="Comment">#define HEXBYTE  std::hex &lt;&lt; std::setw(2) &lt;&lt; std::setfill('0')</span>
+<span id="L403" class="LineNr">403 </span><span class="Comment">#define HEXWORD  std::hex &lt;&lt; std::setw(8) &lt;&lt; std::setfill('0')</span>
+<span id="L404" class="LineNr">404 </span><span class="Comment">// ugly that iostream doesn't print uint8_t as an integer</span>
+<span id="L405" class="LineNr">405 </span><span class="Comment">#define NUM(X) static_cast&lt;int&gt;(X)</span>
+<span id="L406" class="LineNr">406 </span><span class="Comment">#include &lt;stdint.h&gt;</span>
 </pre>
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