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<pre id='vimCodeElement'>
<span id="L1" class="LineNr"> 1 </span><span class="Comment">//: Labels are defined by ending names with a ':'. This layer will compute</span>
<span id="L2" class="LineNr"> 2 </span><span class="Comment">//: addresses for labels, and compute the offset for instructions using them.</span>
<span id="L3" class="LineNr"> 3 </span>
<span id="L4" class="LineNr"> 4 </span><span class="Delimiter">:(scenarios transform)</span>
<span id="L5" class="LineNr"> 5 </span><span class="Delimiter">:(scenario map_label)</span>
<span id="L6" class="LineNr"> 6 </span>== <span class="Constant">0x1</span>
<span id="L7" class="LineNr"> 7 </span> <span class="Comment"># instruction effective address operand displacement immediate</span>
<span id="L8" class="LineNr"> 8 </span> <span class="Comment"># op subop mod rm32 base index scale r32</span>
<span id="L9" class="LineNr"> 9 </span> <span class="Comment"># 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes</span>
<span id="L10" class="LineNr"> 10 </span><span class="Normal">loop</span>:
<span id="L11" class="LineNr"> 11 </span> <span class="PreProc">0</span><span class="Constant">5</span> <span class="Constant">0x0d0c0b0a</span>/imm32 <span class="Comment"># add to EAX</span>
<span id="L12" class="LineNr"> 12 </span><span class="traceContains">+transform: <a href='003trace.cc.html#L73'>label</a> 'loop' is at address 1</span>
<span id="L13" class="LineNr"> 13 </span>
<span id="L14" class="LineNr"> 14 </span><span class="Delimiter">:(before "End Transforms")</span>
<span id="L15" class="LineNr"> 15 </span><a href='011run.cc.html#L184'>Transform</a><span class="Delimiter">.</span>push_back<span class="Delimiter">(</span><a href='034labels.cc.html#L18'>rewrite_labels</a><span class="Delimiter">);</span>
<span id="L16" class="LineNr"> 16 </span>
<span id="L17" class="LineNr"> 17 </span><span class="Delimiter">:(code)</span>
<span id="L18" class="LineNr"> 18 </span><span class="Normal">void</span> <a href='034labels.cc.html#L18'>rewrite_labels</a><span class="Delimiter">(</span>program& p<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L19" class="LineNr"> 19 </span> <a href='003trace.cc.html#L190'>trace</a><span class="Delimiter">(</span><span class="Constant">99</span><span class="Delimiter">,</span> <span class="Constant">"transform"</span><span class="Delimiter">)</span> << <span class="Constant">"-- rewrite labels"</span> << <a href='003trace.cc.html#L215'>end</a><span class="Delimiter">();</span>
<span id="L20" class="LineNr"> 20 </span> <span class="Normal">if</span> <span class="Delimiter">(</span>p<span class="Delimiter">.</span><a href='011run.cc.html#L97'>segments</a><span class="Delimiter">.</span>empty<span class="Delimiter">())</span> <span class="Identifier">return</span><span class="Delimiter">;</span>
<span id="L21" class="LineNr"> 21 </span> segment& code = p<span class="Delimiter">.</span><a href='011run.cc.html#L97'>segments</a><span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">);</span>
<span id="L22" class="LineNr"> 22 </span> map<string<span class="Delimiter">,</span> <span class="Normal">int32_t</span>> address<span class="Delimiter">;</span> <span class="Comment">// values are unsigned, but we're going to do subtractions on them so they need to fit in 31 bits</span>
<span id="L23" class="LineNr"> 23 </span> <a href='034labels.cc.html#L30'>compute_addresses_for_labels</a><span class="Delimiter">(</span>code<span class="Delimiter">,</span> address<span class="Delimiter">);</span>
<span id="L24" class="LineNr"> 24 </span> <span class="Normal">if</span> <span class="Delimiter">(</span><a href='003trace.cc.html#L210'>trace_contains_errors</a><span class="Delimiter">())</span> <span class="Identifier">return</span><span class="Delimiter">;</span>
<span id="L25" class="LineNr"> 25 </span> <a href='034labels.cc.html#L64'>drop_labels</a><span class="Delimiter">(</span>code<span class="Delimiter">);</span>
<span id="L26" class="LineNr"> 26 </span> <span class="Normal">if</span> <span class="Delimiter">(</span><a href='003trace.cc.html#L210'>trace_contains_errors</a><span class="Delimiter">())</span> <span class="Identifier">return</span><span class="Delimiter">;</span>
<span id="L27" class="LineNr"> 27 </span> <a href='034labels.cc.html#L76'>replace_labels_with_addresses</a><span class="Delimiter">(</span>code<span class="Delimiter">,</span> address<span class="Delimiter">);</span>
<span id="L28" class="LineNr"> 28 </span><span class="Delimiter">}</span>
<span id="L29" class="LineNr"> 29 </span>
<span id="L30" class="LineNr"> 30 </span><span class="Normal">void</span> <a href='034labels.cc.html#L30'>compute_addresses_for_labels</a><span class="Delimiter">(</span><span class="Normal">const</span> segment& code<span class="Delimiter">,</span> map<string<span class="Delimiter">,</span> <span class="Normal">int32_t</span>>& address<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L31" class="LineNr"> 31 </span> <span class="Normal">int</span> current_byte = <span class="Constant">0</span><span class="Delimiter">;</span>
<span id="L32" class="LineNr"> 32 </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 < <a href='001help.cc.html#L157'>SIZE</a><span class="Delimiter">(</span>code<span class="Delimiter">.</span><a href='011run.cc.html#L106'>lines</a><span class="Delimiter">);</span> ++i<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L33" class="LineNr"> 33 </span> <span class="Normal">const</span> line& inst = code<span class="Delimiter">.</span><a href='011run.cc.html#L106'>lines</a><span class="Delimiter">.</span>at<span class="Delimiter">(</span>i<span class="Delimiter">);</span>
<span id="L34" class="LineNr"> 34 </span> <span class="Normal">for</span> <span class="Delimiter">(</span><span class="Normal">int</span> j = <span class="Constant">0</span><span class="Delimiter">;</span> j < <a href='001help.cc.html#L157'>SIZE</a><span class="Delimiter">(</span>inst<span class="Delimiter">.</span><a href='011run.cc.html#L111'>words</a><span class="Delimiter">);</span> ++j<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L35" class="LineNr"> 35 </span> <span class="Normal">const</span> word& curr = inst<span class="Delimiter">.</span><a href='011run.cc.html#L111'>words</a><span class="Delimiter">.</span>at<span class="Delimiter">(</span>j<span class="Delimiter">);</span>
<span id="L36" class="LineNr"> 36 </span> <span class="Comment">// hack: if we have any operand metadata left after previous transforms,</span>
<span id="L37" class="LineNr"> 37 </span> <span class="Comment">// deduce its size</span>
<span id="L38" class="LineNr"> 38 </span> <span class="Comment">// Maybe we should just move this transform to before instruction</span>
<span id="L39" class="LineNr"> 39 </span> <span class="Comment">// packing, and deduce the size of *all* operands. But then we'll also</span>
<span id="L40" class="LineNr"> 40 </span> <span class="Comment">// have to deal with bitfields.</span>
<span id="L41" class="LineNr"> 41 </span> <span class="Normal">if</span> <span class="Delimiter">(</span>has_metadata<span class="Delimiter">(</span>curr<span class="Delimiter">,</span> <span class="Constant">"disp32"</span><span class="Delimiter">)</span> || has_metadata<span class="Delimiter">(</span>curr<span class="Delimiter">,</span> <span class="Constant">"imm32"</span><span class="Delimiter">))</span> <span class="Delimiter">{</span>
<span id="L42" class="LineNr"> 42 </span> <span class="Normal">if</span> <span class="Delimiter">(</span>*curr<span class="Delimiter">.</span><a href='011run.cc.html#L117'>data</a><span class="Delimiter">.</span>rbegin<span class="Delimiter">()</span> == <span class="Constant">':'</span><span class="Delimiter">)</span>
<span id="L43" class="LineNr"> 43 </span> <a href='003trace.cc.html#L197'>raise</a> << <span class="Constant">"'"</span> << to_string<span class="Delimiter">(</span>inst<span class="Delimiter">)</span> << <span class="Constant">"': don't use ':' when jumping to labels</span><span class="cSpecial">\n</span><span class="Constant">"</span> << end<span class="Delimiter">();</span>
<span id="L44" class="LineNr"> 44 </span> current_byte += <span class="Constant">4</span><span class="Delimiter">;</span>
<span id="L45" class="LineNr"> 45 </span> <span class="Delimiter">}</span>
<span id="L46" class="LineNr"> 46 </span> <span class="Comment">// automatically handle /disp8 and /imm8 here</span>
<span id="L47" class="LineNr"> 47 </span> <span class="Normal">else</span> <span class="Normal">if</span> <span class="Delimiter">(</span>*curr<span class="Delimiter">.</span><a href='011run.cc.html#L117'>data</a><span class="Delimiter">.</span>rbegin<span class="Delimiter">()</span> != <span class="Constant">':'</span><span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L48" class="LineNr"> 48 </span> ++current_byte<span class="Delimiter">;</span>
<span id="L49" class="LineNr"> 49 </span> <span class="Delimiter">}</span>
<span id="L50" class="LineNr"> 50 </span> <span class="Normal">else</span> <span class="Delimiter">{</span>
<span id="L51" class="LineNr"> 51 </span> <span class="Normal">if</span> <span class="Delimiter">(</span><a href='030check_operands.cc.html#L344'>contains_any_operand_metadata</a><span class="Delimiter">(</span>curr<span class="Delimiter">))</span>
<span id="L52" class="LineNr"> 52 </span> <a href='003trace.cc.html#L197'>raise</a> << <span class="Constant">"'"</span> << to_string<span class="Delimiter">(</span>inst<span class="Delimiter">)</span> << <span class="Constant">"': <a href='003trace.cc.html#L73'>label</a> definition (':') not allowed in operand</span><span class="cSpecial">\n</span><span class="Constant">"</span> << <a href='003trace.cc.html#L215'>end</a><span class="Delimiter">();</span>
<span id="L53" class="LineNr"> 53 </span> <span class="Normal">if</span> <span class="Delimiter">(</span>j > <span class="Constant">0</span><span class="Delimiter">)</span>
<span id="L54" class="LineNr"> 54 </span> <a href='003trace.cc.html#L197'>raise</a> << <span class="Constant">"'"</span> << to_string<span class="Delimiter">(</span>inst<span class="Delimiter">)</span> << <span class="Constant">"': labels can only be the first <a href='011run.cc.html#L115'>word</a> in a line.</span><span class="cSpecial">\n</span><span class="Constant">"</span> << <a href='003trace.cc.html#L215'>end</a><span class="Delimiter">();</span>
<span id="L55" class="LineNr"> 55 </span> string <a href='003trace.cc.html#L73'>label</a> = curr<span class="Delimiter">.</span><a href='011run.cc.html#L117'>data</a><span class="Delimiter">.</span>substr<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">,</span> <a href='001help.cc.html#L157'>SIZE</a><span class="Delimiter">(</span>curr<span class="Delimiter">.</span><a href='011run.cc.html#L117'>data</a><span class="Delimiter">)</span>-<span class="Constant">1</span><span class="Delimiter">);</span>
<span id="L56" class="LineNr"> 56 </span> <a href='001help.cc.html#L243'>put</a><span class="Delimiter">(</span>address<span class="Delimiter">,</span> <a href='003trace.cc.html#L73'>label</a><span class="Delimiter">,</span> current_byte<span class="Delimiter">);</span>
<span id="L57" class="LineNr"> 57 </span> <a href='003trace.cc.html#L190'>trace</a><span class="Delimiter">(</span><span class="Constant">99</span><span class="Delimiter">,</span> <span class="Constant">"transform"</span><span class="Delimiter">)</span> << <span class="Constant">"label '"</span> << label << <span class="Constant">"' is at address "</span> << <span class="Delimiter">(</span>current_byte+code<span class="Delimiter">.</span><a href='011run.cc.html#L105'>start</a><span class="Delimiter">)</span> << <a href='003trace.cc.html#L215'>end</a><span class="Delimiter">();</span>
<span id="L58" class="LineNr"> 58 </span> <span class="Comment">// no modifying current_byte; label definitions won't be in the final binary</span>
<span id="L59" class="LineNr"> 59 </span> <span class="Delimiter">}</span>
<span id="L60" class="LineNr"> 60 </span> <span class="Delimiter">}</span>
<span id="L61" class="LineNr"> 61 </span> <span class="Delimiter">}</span>
<span id="L62" class="LineNr"> 62 </span><span class="Delimiter">}</span>
<span id="L63" class="LineNr"> 63 </span>
<span id="L64" class="LineNr"> 64 </span><span class="Normal">void</span> <a href='034labels.cc.html#L64'>drop_labels</a><span class="Delimiter">(</span>segment& code<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L65" class="LineNr"> 65 </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 < <a href='001help.cc.html#L157'>SIZE</a><span class="Delimiter">(</span>code<span class="Delimiter">.</span><a href='011run.cc.html#L106'>lines</a><span class="Delimiter">);</span> ++i<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L66" class="LineNr"> 66 </span> line& inst = code<span class="Delimiter">.</span><a href='011run.cc.html#L106'>lines</a><span class="Delimiter">.</span>at<span class="Delimiter">(</span>i<span class="Delimiter">);</span>
<span id="L67" class="LineNr"> 67 </span> vector<word>::iterator new_end = remove_if<span class="Delimiter">(</span>inst<span class="Delimiter">.</span><a href='011run.cc.html#L111'>words</a><span class="Delimiter">.</span>begin<span class="Delimiter">(),</span> inst<span class="Delimiter">.</span><a href='011run.cc.html#L111'>words</a><span class="Delimiter">.</span><a href='003trace.cc.html#L215'>end</a><span class="Delimiter">(),</span> <a href='034labels.cc.html#L72'>is_label</a><span class="Delimiter">);</span>
<span id="L68" class="LineNr"> 68 </span> inst<span class="Delimiter">.</span><a href='011run.cc.html#L111'>words</a><span class="Delimiter">.</span>erase<span class="Delimiter">(</span>new_end<span class="Delimiter">,</span> inst<span class="Delimiter">.</span><a href='011run.cc.html#L111'>words</a><span class="Delimiter">.</span><a href='003trace.cc.html#L215'>end</a><span class="Delimiter">());</span>
<span id="L69" class="LineNr"> 69 </span> <span class="Delimiter">}</span>
<span id="L70" class="LineNr"> 70 </span><span class="Delimiter">}</span>
<span id="L71" class="LineNr"> 71 </span>
<span id="L72" class="LineNr"> 72 </span><span class="Normal">bool</span> <a href='034labels.cc.html#L72'>is_label</a><span class="Delimiter">(</span><span class="Normal">const</span> word& w<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L73" class="LineNr"> 73 </span> <span class="Identifier">return</span> *w<span class="Delimiter">.</span><a href='011run.cc.html#L117'>data</a><span class="Delimiter">.</span>rbegin<span class="Delimiter">()</span> == <span class="Constant">':'</span><span class="Delimiter">;</span>
<span id="L74" class="LineNr"> 74 </span><span class="Delimiter">}</span>
<span id="L75" class="LineNr"> 75 </span>
<span id="L76" class="LineNr"> 76 </span><span class="Normal">void</span> <a href='034labels.cc.html#L76'>replace_labels_with_addresses</a><span class="Delimiter">(</span>segment& code<span class="Delimiter">,</span> <span class="Normal">const</span> map<string<span class="Delimiter">,</span> <span class="Normal">int32_t</span>>& address<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L77" class="LineNr"> 77 </span> <span class="Normal">int32_t</span> byte_next_instruction_starts_at = <span class="Constant">0</span><span class="Delimiter">;</span>
<span id="L78" class="LineNr"> 78 </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 < <a href='001help.cc.html#L157'>SIZE</a><span class="Delimiter">(</span>code<span class="Delimiter">.</span><a href='011run.cc.html#L106'>lines</a><span class="Delimiter">);</span> ++i<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L79" class="LineNr"> 79 </span> line& inst = code<span class="Delimiter">.</span><a href='011run.cc.html#L106'>lines</a><span class="Delimiter">.</span>at<span class="Delimiter">(</span>i<span class="Delimiter">);</span>
<span id="L80" class="LineNr"> 80 </span> byte_next_instruction_starts_at += <a href='034labels.cc.html#L112'>num_bytes</a><span class="Delimiter">(</span>inst<span class="Delimiter">);</span>
<span id="L81" class="LineNr"> 81 </span> <a href='011run.cc.html#L110'>line</a> new_inst<span class="Delimiter">;</span>
<span id="L82" class="LineNr"> 82 </span> <span class="Normal">for</span> <span class="Delimiter">(</span><span class="Normal">int</span> j = <span class="Constant">0</span><span class="Delimiter">;</span> j < <a href='001help.cc.html#L157'>SIZE</a><span class="Delimiter">(</span>inst<span class="Delimiter">.</span><a href='011run.cc.html#L111'>words</a><span class="Delimiter">);</span> ++j<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L83" class="LineNr"> 83 </span> <span class="Normal">const</span> word& curr = inst<span class="Delimiter">.</span><a href='011run.cc.html#L111'>words</a><span class="Delimiter">.</span>at<span class="Delimiter">(</span>j<span class="Delimiter">);</span>
<span id="L84" class="LineNr"> 84 </span> <span class="Normal">if</span> <span class="Delimiter">(</span><a href='001help.cc.html#L247'>contains_key</a><span class="Delimiter">(</span>address<span class="Delimiter">,</span> curr<span class="Delimiter">.</span><a href='011run.cc.html#L117'>data</a><span class="Delimiter">))</span> <span class="Delimiter">{</span>
<span id="L85" class="LineNr"> 85 </span> <span class="Normal">int32_t</span> offset = <span class="Normal">static_cast</span><<span class="Normal">int32_t</span>><span class="Delimiter">(</span>get<span class="Delimiter">(</span>address<span class="Delimiter">,</span> curr<span class="Delimiter">.</span><a href='011run.cc.html#L117'>data</a><span class="Delimiter">))</span> - byte_next_instruction_starts_at<span class="Delimiter">;</span>
<span id="L86" class="LineNr"> 86 </span> <span class="Normal">if</span> <span class="Delimiter">(</span>has_metadata<span class="Delimiter">(</span>curr<span class="Delimiter">,</span> <span class="Constant">"disp8"</span><span class="Delimiter">)</span> || has_metadata<span class="Delimiter">(</span>curr<span class="Delimiter">,</span> <span class="Constant">"imm8"</span><span class="Delimiter">))</span> <span class="Delimiter">{</span>
<span id="L87" class="LineNr"> 87 </span> <span class="Normal">if</span> <span class="Delimiter">(</span>offset > <span class="Constant">0xff</span> || offset < -<span class="Constant">0x7f</span><span class="Delimiter">)</span>
<span id="L88" class="LineNr"> 88 </span> <a href='003trace.cc.html#L197'>raise</a> << <span class="Constant">"'"</span> << to_string<span class="Delimiter">(</span>inst<span class="Delimiter">)</span> << <span class="Constant">"': <a href='003trace.cc.html#L73'>label</a> too far away for distance "</span> << std::hex << offset << <span class="Constant">" to fit in 8 bits</span><span class="cSpecial">\n</span><span class="Constant">"</span> << <a href='003trace.cc.html#L215'>end</a><span class="Delimiter">();</span>
<span id="L89" class="LineNr"> 89 </span> <span class="Normal">else</span>
<span id="L90" class="LineNr"> 90 </span> emit_hex_bytes<span class="Delimiter">(</span>new_inst<span class="Delimiter">,</span> offset<span class="Delimiter">,</span> <span class="Constant">1</span><span class="Delimiter">);</span>
<span id="L91" class="LineNr"> 91 </span> <span class="Delimiter">}</span>
<span id="L92" class="LineNr"> 92 </span> <span class="Normal">else</span> <span class="Normal">if</span> <span class="Delimiter">(</span>has_metadata<span class="Delimiter">(</span>curr<span class="Delimiter">,</span> <span class="Constant">"disp16"</span><span class="Delimiter">))</span> <span class="Delimiter">{</span>
<span id="L93" class="LineNr"> 93 </span> <span class="Normal">if</span> <span class="Delimiter">(</span>offset > <span class="Constant">0xffff</span> || offset < -<span class="Constant">0x7fff</span><span class="Delimiter">)</span>
<span id="L94" class="LineNr"> 94 </span> <a href='003trace.cc.html#L197'>raise</a> << <span class="Constant">"'"</span> << to_string<span class="Delimiter">(</span>inst<span class="Delimiter">)</span> << <span class="Constant">"': <a href='003trace.cc.html#L73'>label</a> too far away for distance "</span> << std::hex << offset << <span class="Constant">" to fit in 16 bits</span><span class="cSpecial">\n</span><span class="Constant">"</span> << <a href='003trace.cc.html#L215'>end</a><span class="Delimiter">();</span>
<span id="L95" class="LineNr"> 95 </span> <span class="Normal">else</span>
<span id="L96" class="LineNr"> 96 </span> emit_hex_bytes<span class="Delimiter">(</span>new_inst<span class="Delimiter">,</span> offset<span class="Delimiter">,</span> <span class="Constant">2</span><span class="Delimiter">);</span>
<span id="L97" class="LineNr"> 97 </span> <span class="Delimiter">}</span>
<span id="L98" class="LineNr"> 98 </span> <span class="Normal">else</span> <span class="Normal">if</span> <span class="Delimiter">(</span>has_metadata<span class="Delimiter">(</span>curr<span class="Delimiter">,</span> <span class="Constant">"disp32"</span><span class="Delimiter">)</span> || has_metadata<span class="Delimiter">(</span>curr<span class="Delimiter">,</span> <span class="Constant">"imm32"</span><span class="Delimiter">))</span> <span class="Delimiter">{</span>
<span id="L99" class="LineNr"> 99 </span> emit_hex_bytes<span class="Delimiter">(</span>new_inst<span class="Delimiter">,</span> offset<span class="Delimiter">,</span> <span class="Constant">4</span><span class="Delimiter">);</span>
<span id="L100" class="LineNr">100 </span> <span class="Delimiter">}</span>
<span id="L101" class="LineNr">101 </span> <span class="Delimiter">}</span>
<span id="L102" class="LineNr">102 </span> <span class="Normal">else</span> <span class="Delimiter">{</span>
<span id="L103" class="LineNr">103 </span> new_inst<span class="Delimiter">.</span><a href='011run.cc.html#L111'>words</a><span class="Delimiter">.</span>push_back<span class="Delimiter">(</span>curr<span class="Delimiter">);</span>
<span id="L104" class="LineNr">104 </span> <span class="Delimiter">}</span>
<span id="L105" class="LineNr">105 </span> <span class="Delimiter">}</span>
<span id="L106" class="LineNr">106 </span> inst<span class="Delimiter">.</span><a href='011run.cc.html#L111'>words</a><span class="Delimiter">.</span>swap<span class="Delimiter">(</span>new_inst<span class="Delimiter">.</span><a href='011run.cc.html#L111'>words</a><span class="Delimiter">);</span>
<span id="L107" class="LineNr">107 </span> <a href='003trace.cc.html#L190'>trace</a><span class="Delimiter">(</span><span class="Constant">99</span><span class="Delimiter">,</span> <span class="Constant">"transform"</span><span class="Delimiter">)</span> << <span class="Constant">"instruction after transform: '"</span> << data_to_string<span class="Delimiter">(</span>inst<span class="Delimiter">)</span> << <span class="Constant">"'"</span> << <a href='003trace.cc.html#L215'>end</a><span class="Delimiter">();</span>
<span id="L108" class="LineNr">108 </span> <span class="Delimiter">}</span>
<span id="L109" class="LineNr">109 </span><span class="Delimiter">}</span>
<span id="L110" class="LineNr">110 </span>
<span id="L111" class="LineNr">111 </span><span class="Comment">// Assumes all bitfields are packed.</span>
<span id="L112" class="LineNr">112 </span><span class="Normal">uint32_t</span> <a href='034labels.cc.html#L112'>num_bytes</a><span class="Delimiter">(</span><span class="Normal">const</span> line& inst<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L113" class="LineNr">113 </span> <span class="Normal">uint32_t</span> sum = <span class="Constant">0</span><span class="Delimiter">;</span>
<span id="L114" class="LineNr">114 </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 < <a href='001help.cc.html#L157'>SIZE</a><span class="Delimiter">(</span>inst<span class="Delimiter">.</span><a href='011run.cc.html#L111'>words</a><span class="Delimiter">);</span> ++i<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L115" class="LineNr">115 </span> <span class="Normal">const</span> word& curr = inst<span class="Delimiter">.</span><a href='011run.cc.html#L111'>words</a><span class="Delimiter">.</span>at<span class="Delimiter">(</span>i<span class="Delimiter">);</span>
<span id="L116" class="LineNr">116 </span> <span class="Normal">if</span> <span class="Delimiter">(</span>has_metadata<span class="Delimiter">(</span>curr<span class="Delimiter">,</span> <span class="Constant">"disp32"</span><span class="Delimiter">)</span> || has_metadata<span class="Delimiter">(</span>curr<span class="Delimiter">,</span> <span class="Constant">"imm32"</span><span class="Delimiter">))</span> <span class="Comment">// only multi-byte operands</span>
<span id="L117" class="LineNr">117 </span> sum += <span class="Constant">4</span><span class="Delimiter">;</span>
<span id="L118" class="LineNr">118 </span> <span class="Normal">else</span>
<span id="L119" class="LineNr">119 </span> sum++<span class="Delimiter">;</span>
<span id="L120" class="LineNr">120 </span> <span class="Delimiter">}</span>
<span id="L121" class="LineNr">121 </span> <span class="Identifier">return</span> sum<span class="Delimiter">;</span>
<span id="L122" class="LineNr">122 </span><span class="Delimiter">}</span>
<span id="L123" class="LineNr">123 </span>
<span id="L124" class="LineNr">124 </span>string <a href='034labels.cc.html#L124'>data_to_string</a><span class="Delimiter">(</span><span class="Normal">const</span> line& inst<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L125" class="LineNr">125 </span> ostringstream out<span class="Delimiter">;</span>
<span id="L126" class="LineNr">126 </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 < <a href='001help.cc.html#L157'>SIZE</a><span class="Delimiter">(</span>inst<span class="Delimiter">.</span><a href='011run.cc.html#L111'>words</a><span class="Delimiter">);</span> ++i<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span id="L127" class="LineNr">127 </span> <span class="Normal">if</span> <span class="Delimiter">(</span>i > <span class="Constant">0</span><span class="Delimiter">)</span> out << <span class="Constant">' '</span><span class="Delimiter">;</span>
<span id="L128" class="LineNr">128 </span> out << inst<span class="Delimiter">.</span><a href='011run.cc.html#L111'>words</a><span class="Delimiter">.</span>at<span class="Delimiter">(</span>i<span class="Delimiter">).</span><a href='011run.cc.html#L117'>data</a><span class="Delimiter">;</span>
<span id="L129" class="LineNr">129 </span> <span class="Delimiter">}</span>
<span id="L130" class="LineNr">130 </span> <span class="Identifier">return</span> out<span class="Delimiter">.</span>str<span class="Delimiter">();</span>
<span id="L131" class="LineNr">131 </span><span class="Delimiter">}</span>
<span id="L132" class="LineNr">132 </span>
<span id="L133" class="LineNr">133 </span><span class="Comment">//: Label definitions must be the first word on a line. No jumping inside</span>
<span id="L134" class="LineNr">134 </span><span class="Comment">//: instructions.</span>
<span id="L135" class="LineNr">135 </span><span class="Comment">//: They should also be the only word on a line.</span>
<span id="L136" class="LineNr">136 </span><span class="Comment">//: However, you can absolutely have multiple labels map to the same address,</span>
<span id="L137" class="LineNr">137 </span><span class="Comment">//: as long as they're on separate lines.</span>
<span id="L138" class="LineNr">138 </span>
<span id="L139" class="LineNr">139 </span><span class="Delimiter">:(scenario multiple_labels_at)</span>
<span id="L140" class="LineNr">140 </span>== <span class="Constant">0x1</span>
<span id="L141" class="LineNr">141 </span> <span class="Comment"># instruction effective address operand displacement immediate</span>
<span id="L142" class="LineNr">142 </span> <span class="Comment"># op subop mod rm32 base index scale r32</span>
<span id="L143" class="LineNr">143 </span> <span class="Comment"># 1-3 bytes 3 bits 2 bits 3 bits 3 bits 3 bits 2 bits 2 bits 0/1/2/4 bytes 0/1/2/4 bytes</span>
<span id="L144" class="LineNr">144 </span><span class="Comment"># address 1</span>
<span id="L145" class="LineNr">145 </span><span class="Normal">loop</span>:
<span id="L146" class="LineNr">146 </span><span class="Normal">loop2</span>:
<span id="L147" class="LineNr">147 </span><span class="Comment"># address 1 (labels take up no space)</span>
<span id="L148" class="LineNr">148 </span> <span class="PreProc">0</span><span class="Constant">5</span> <span class="Constant">0x0d0c0b0a</span>/imm32 <span class="Comment"># add to EAX</span>
<span id="L149" class="LineNr">149 </span><span class="Comment"># address 6</span>
<span id="L150" class="LineNr">150 </span> eb loop2/disp8
<span id="L151" class="LineNr">151 </span><span class="Comment"># address 8</span>
<span id="L152" class="LineNr">152 </span> eb loop3/disp8
<span id="L153" class="LineNr">153 </span><span class="Comment"># address 10</span>
<span id="L154" class="LineNr">154 </span><span class="Normal">loop3</span>:
<span id="L155" class="LineNr">155 </span><span class="traceContains">+transform: <a href='003trace.cc.html#L73'>label</a> 'loop' is at address 1</span>
<span id="L156" class="LineNr">156 </span><span class="traceContains">+transform: <a href='003trace.cc.html#L73'>label</a> 'loop2' is at address 1</span>
<span id="L157" class="LineNr">157 </span><span class="traceContains">+transform: <a href='003trace.cc.html#L73'>label</a> 'loop3' is at address 10</span>
<span id="L158" class="LineNr">158 </span><span class="Comment"># first jump is to -7</span>
<span id="L159" class="LineNr">159 </span><span class="traceContains">+transform: instruction after transform: 'eb f9'</span>
<span id="L160" class="LineNr">160 </span><span class="Comment"># second jump is to 0 (fall through)</span>
<span id="L161" class="LineNr">161 </span><span class="traceContains">+transform: instruction after transform: 'eb 00'</span>
</pre>
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