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<span class="Comment">//: Support jumps to a specific label (the 'jump target') in the same recipe.</span>
<span class="Comment">//: Jump targets must be unique and unambiguous within any recipe.</span>
<span class="Comment">//:</span>
<span class="Comment">//: The 'break' and 'loop' pseudo instructions can also take jump targets.</span>
<span class="Comment">//: Which instruction you use is just documentation about intent; use 'break'</span>
<span class="Comment">//: to indicate you're exiting one or more loop nests, and 'loop' to indicate</span>
<span class="Comment">//: you're skipping to the next iteration of some containing loop nest.</span>
<span class="Comment">//: Since they have to be unique in a recipe, not all labels can be jump</span>
<span class="Comment">//: targets.</span>
<span class="Normal">bool</span> is_jump_target<span class="Delimiter">(</span><span class="Normal">const</span> string& label<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span class="Normal">if</span> <span class="Delimiter">(</span>label == <span class="Constant">"{"</span> || label == <span class="Constant">"}"</span><span class="Delimiter">)</span> <span class="Identifier">return</span> <span class="Constant">false</span><span class="Delimiter">;</span>
<span class="Comment">// End is_jump_target Special-cases</span>
<span class="Identifier">return</span> is_label_word<span class="Delimiter">(</span>label<span class="Delimiter">);</span>
<span class="Delimiter">}</span>
<span class="Delimiter">:(scenario jump_to_label)</span>
<span class="muRecipe">def</span> main [
jump <span class="Constant">+target:label</span>
<span class="Constant">1</span>:num<span class="Special"> <- </span>copy <span class="Constant">0</span>
+target
]
<span class="traceAbsent">-mem: storing 0 in location 1</span>
<span class="Delimiter">:(before "End Mu Types Initialization")</span>
put<span class="Delimiter">(</span>Type_ordinal<span class="Delimiter">,</span> <span class="Constant">"label"</span><span class="Delimiter">,</span> <span class="Constant">0</span><span class="Delimiter">);</span>
<span class="Delimiter">:(before "End Instruction Modifying Transforms")</span>
Transform<span class="Delimiter">.</span>push_back<span class="Delimiter">(</span>transform_labels<span class="Delimiter">);</span> <span class="Comment">// idempotent</span>
<span class="Delimiter">:(code)</span>
<span class="Normal">void</span> transform_labels<span class="Delimiter">(</span><span class="Normal">const</span> recipe_ordinal r<span class="Delimiter">)</span> <span class="Delimiter">{</span>
map<string<span class="Delimiter">,</span> <span class="Normal">int</span>> offset<span class="Delimiter">;</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 < SIZE<span class="Delimiter">(</span>get<span class="Delimiter">(</span>Recipe<span class="Delimiter">,</span> r<span class="Delimiter">).</span>steps<span class="Delimiter">);</span> ++i<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span class="Normal">const</span> instruction& inst = get<span class="Delimiter">(</span>Recipe<span class="Delimiter">,</span> r<span class="Delimiter">).</span>steps<span class="Delimiter">.</span>at<span class="Delimiter">(</span>i<span class="Delimiter">);</span>
<span class="Normal">if</span> <span class="Delimiter">(</span>!inst<span class="Delimiter">.</span>is_label<span class="Delimiter">)</span> <span class="Identifier">continue</span><span class="Delimiter">;</span>
<span class="Normal">if</span> <span class="Delimiter">(</span>is_jump_target<span class="Delimiter">(</span>inst<span class="Delimiter">.</span>label<span class="Delimiter">))</span> <span class="Delimiter">{</span>
<span class="Normal">if</span> <span class="Delimiter">(</span>!contains_key<span class="Delimiter">(</span>offset<span class="Delimiter">,</span> inst<span class="Delimiter">.</span>label<span class="Delimiter">))</span> <span class="Delimiter">{</span>
put<span class="Delimiter">(</span>offset<span class="Delimiter">,</span> inst<span class="Delimiter">.</span>label<span class="Delimiter">,</span> i<span class="Delimiter">);</span>
<span class="Delimiter">}</span>
<span class="Normal">else</span> <span class="Delimiter">{</span>
raise << maybe<span class="Delimiter">(</span>get<span class="Delimiter">(</span>Recipe<span class="Delimiter">,</span> r<span class="Delimiter">).</span>name<span class="Delimiter">)</span> << <span class="Constant">"duplicate label '"</span> << inst<span class="Delimiter">.</span>label << <span class="Constant">"'"</span> << end<span class="Delimiter">();</span>
<span class="Comment">// have all jumps skip some random but noticeable and deterministic amount of code</span>
put<span class="Delimiter">(</span>offset<span class="Delimiter">,</span> inst<span class="Delimiter">.</span>label<span class="Delimiter">,</span> <span class="Constant">9999</span><span class="Delimiter">);</span>
<span class="Delimiter">}</span>
<span class="Delimiter">}</span>
<span class="Delimiter">}</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 < SIZE<span class="Delimiter">(</span>get<span class="Delimiter">(</span>Recipe<span class="Delimiter">,</span> r<span class="Delimiter">).</span>steps<span class="Delimiter">);</span> ++i<span class="Delimiter">)</span> <span class="Delimiter">{</span>
instruction& inst = get<span class="Delimiter">(</span>Recipe<span class="Delimiter">,</span> r<span class="Delimiter">).</span>steps<span class="Delimiter">.</span>at<span class="Delimiter">(</span>i<span class="Delimiter">);</span>
<span class="Normal">if</span> <span class="Delimiter">(</span>inst<span class="Delimiter">.</span>name == <span class="Constant">"jump"</span><span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span class="Normal">if</span> <span class="Delimiter">(</span>inst<span class="Delimiter">.</span>ingredients<span class="Delimiter">.</span>empty<span class="Delimiter">())</span> <span class="Delimiter">{</span>
raise << maybe<span class="Delimiter">(</span>get<span class="Delimiter">(</span>Recipe<span class="Delimiter">,</span> r<span class="Delimiter">).</span>name<span class="Delimiter">)</span> << <span class="Constant">"'jump' expects an ingredient but got none</span><span class="cSpecial">\n</span><span class="Constant">"</span> << end<span class="Delimiter">();</span>
<span class="Identifier">return</span><span class="Delimiter">;</span>
<span class="Delimiter">}</span>
replace_offset<span class="Delimiter">(</span>inst<span class="Delimiter">.</span>ingredients<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">),</span> offset<span class="Delimiter">,</span> i<span class="Delimiter">,</span> r<span class="Delimiter">);</span>
<span class="Delimiter">}</span>
<span class="Normal">if</span> <span class="Delimiter">(</span>inst<span class="Delimiter">.</span>name == <span class="Constant">"jump-if"</span> || inst<span class="Delimiter">.</span>name == <span class="Constant">"jump-unless"</span><span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span class="Normal">if</span> <span class="Delimiter">(</span>SIZE<span class="Delimiter">(</span>inst<span class="Delimiter">.</span>ingredients<span class="Delimiter">)</span> < <span class="Constant">2</span><span class="Delimiter">)</span> <span class="Delimiter">{</span>
raise << maybe<span class="Delimiter">(</span>get<span class="Delimiter">(</span>Recipe<span class="Delimiter">,</span> r<span class="Delimiter">).</span>name<span class="Delimiter">)</span> << <span class="Constant">"'"</span> << inst<span class="Delimiter">.</span>name << <span class="Constant">"' expects 2 ingredients but got "</span> << SIZE<span class="Delimiter">(</span>inst<span class="Delimiter">.</span>ingredients<span class="Delimiter">)</span> << <span class="cSpecial">'\n'</span> << end<span class="Delimiter">();</span>
<span class="Identifier">return</span><span class="Delimiter">;</span>
<span class="Delimiter">}</span>
replace_offset<span class="Delimiter">(</span>inst<span class="Delimiter">.</span>ingredients<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">),</span> offset<span class="Delimiter">,</span> i<span class="Delimiter">,</span> r<span class="Delimiter">);</span>
<span class="Delimiter">}</span>
<span class="Normal">if</span> <span class="Delimiter">((</span>inst<span class="Delimiter">.</span>name == <span class="Constant">"loop"</span> || inst<span class="Delimiter">.</span>name == <span class="Constant">"break"</span><span class="Delimiter">)</span>
&& SIZE<span class="Delimiter">(</span>inst<span class="Delimiter">.</span>ingredients<span class="Delimiter">)</span> >= <span class="Constant">1</span><span class="Delimiter">)</span> <span class="Delimiter">{</span>
replace_offset<span class="Delimiter">(</span>inst<span class="Delimiter">.</span>ingredients<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">),</span> offset<span class="Delimiter">,</span> i<span class="Delimiter">,</span> r<span class="Delimiter">);</span>
<span class="Delimiter">}</span>
<span class="Normal">if</span> <span class="Delimiter">((</span>inst<span class="Delimiter">.</span>name == <span class="Constant">"loop-if"</span> || inst<span class="Delimiter">.</span>name == <span class="Constant">"loop-unless"</span>
|| inst<span class="Delimiter">.</span>name == <span class="Constant">"break-if"</span> || inst<span class="Delimiter">.</span>name == <span class="Constant">"break-unless"</span><span class="Delimiter">)</span>
&& SIZE<span class="Delimiter">(</span>inst<span class="Delimiter">.</span>ingredients<span class="Delimiter">)</span> >= <span class="Constant">2</span><span class="Delimiter">)</span> <span class="Delimiter">{</span>
replace_offset<span class="Delimiter">(</span>inst<span class="Delimiter">.</span>ingredients<span class="Delimiter">.</span>at<span class="Delimiter">(</span><span class="Constant">1</span><span class="Delimiter">),</span> offset<span class="Delimiter">,</span> i<span class="Delimiter">,</span> r<span class="Delimiter">);</span>
<span class="Delimiter">}</span>
<span class="Delimiter">}</span>
<span class="Delimiter">}</span>
<span class="Normal">void</span> replace_offset<span class="Delimiter">(</span>reagent& x<span class="Delimiter">,</span> <span class="Comment">/*</span><span class="Comment">const</span><span class="Comment">*/</span> map<string<span class="Delimiter">,</span> <span class="Normal">int</span>>& offset<span class="Delimiter">,</span> <span class="Normal">const</span> <span class="Normal">int</span> current_offset<span class="Delimiter">,</span> <span class="Normal">const</span> recipe_ordinal r<span class="Delimiter">)</span> <span class="Delimiter">{</span>
<span class="Normal">if</span> <span class="Delimiter">(</span>!is_literal<span class="Delimiter">(</span>x<span class="Delimiter">))</span> <span class="Delimiter">{</span>
raise << maybe<span class="Delimiter">(</span>get<span class="Delimiter">(</span>Recipe<span class="Delimiter">,</span> r<span class="Delimiter">).</span>name<span class="Delimiter">)</span> << <span class="Constant">"jump target must be offset or label but is '"</span> << x<span class="Delimiter">.</span>original_string << <span class="Constant">"'</span><span class="cSpecial">\n</span><span class="Constant">"</span> << end<span class="Delimiter">();</span>
x<span class="Delimiter">.</span>set_value<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">);</span> <span class="Comment">// no jump by default</span>
<span class="Identifier">return</span><span class="Delimiter">;</span>
<span class="Delimiter">}</span>
<span class="Normal">if</span> <span class="Delimiter">(</span>x<span class="Delimiter">.</span>initialized<span class="Delimiter">)</span> <span class="Identifier">return</span><span class="Delimiter">;</span>
<span class="Normal">if</span> <span class="Delimiter">(</span>is_integer<span class="Delimiter">(</span>x<span class="Delimiter">.</span>name<span class="Delimiter">))</span> <span class="Identifier">return</span><span class="Delimiter">;</span> <span class="Comment">// non-labels will be handled like other number operands</span>
<span class="Normal">if</span> <span class="Delimiter">(</span>!is_jump_target<span class="Delimiter">(</span>x<span class="Delimiter">.</span>name<span class="Delimiter">))</span> <span class="Delimiter">{</span>
raise << maybe<span class="Delimiter">(</span>get<span class="Delimiter">(</span>Recipe<span class="Delimiter">,</span> r<span class="Delimiter">).</span>name<span class="Delimiter">)</span> << <span class="Constant">"can't jump to label '"</span> << x<span class="Delimiter">.</span>name << <span class="Constant">"'</span><span class="cSpecial">\n</span><span class="Constant">"</span> << end<span class="Delimiter">();</span>
x<span class="Delimiter">.</span>set_value<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">);</span> <span class="Comment">// no jump by default</span>
<span class="Identifier">return</span><span class="Delimiter">;</span>
<span class="Delimiter">}</span>
<span class="Normal">if</span> <span class="Delimiter">(</span>!contains_key<span class="Delimiter">(</span>offset<span class="Delimiter">,</span> x<span class="Delimiter">.</span>name<span class="Delimiter">))</span> <span class="Delimiter">{</span>
raise << maybe<span class="Delimiter">(</span>get<span class="Delimiter">(</span>Recipe<span class="Delimiter">,</span> r<span class="Delimiter">).</span>name<span class="Delimiter">)</span> << <span class="Constant">"can't find label '"</span> << x<span class="Delimiter">.</span>name << <span class="Constant">"'</span><span class="cSpecial">\n</span><span class="Constant">"</span> << end<span class="Delimiter">();</span>
x<span class="Delimiter">.</span>set_value<span class="Delimiter">(</span><span class="Constant">0</span><span class="Delimiter">);</span> <span class="Comment">// no jump by default</span>
<span class="Identifier">return</span><span class="Delimiter">;</span>
<span class="Delimiter">}</span>
x<span class="Delimiter">.</span>set_value<span class="Delimiter">(</span>get<span class="Delimiter">(</span>offset<span class="Delimiter">,</span> x<span class="Delimiter">.</span>name<span class="Delimiter">)</span> - current_offset<span class="Delimiter">);</span>
<span class="Delimiter">}</span>
<span class="Delimiter">:(scenario break_to_label)</span>
<span class="muRecipe">def</span> main [
<span class="Delimiter">{</span>
<span class="Delimiter">{</span>
<span class="Identifier">break</span> <span class="Constant">+target:label</span>
<span class="Constant">1</span>:num<span class="Special"> <- </span>copy <span class="Constant">0</span>
<span class="Delimiter">}</span>
<span class="Delimiter">}</span>
+target
]
<span class="traceAbsent">-mem: storing 0 in location 1</span>
<span class="Delimiter">:(scenario jump_if_to_label)</span>
<span class="muRecipe">def</span> main [
<span class="Delimiter">{</span>
<span class="Delimiter">{</span>
jump-<span class="Normal">if</span> <span class="Constant">1</span><span class="Delimiter">,</span> <span class="Constant">+target:label</span>
<span class="Constant">1</span>:num<span class="Special"> <- </span>copy <span class="Constant">0</span>
<span class="Delimiter">}</span>
<span class="Delimiter">}</span>
+target
]
<span class="traceAbsent">-mem: storing 0 in location 1</span>
<span class="Delimiter">:(scenario loop_unless_to_label)</span>
<span class="muRecipe">def</span> main [
<span class="Delimiter">{</span>
<span class="Delimiter">{</span>
loop-unless <span class="Constant">0</span><span class="Delimiter">,</span> <span class="Constant">+target:label</span> <span class="Comment"># loop/break with a label don't care about braces</span>
<span class="Constant">1</span>:num<span class="Special"> <- </span>copy <span class="Constant">0</span>
<span class="Delimiter">}</span>
<span class="Delimiter">}</span>
+target
]
<span class="traceAbsent">-mem: storing 0 in location 1</span>
<span class="Delimiter">:(scenario jump_runs_code_after_label)</span>
<span class="muRecipe">def</span> main [
<span class="Comment"># first a few lines of padding to exercise the offset computation</span>
<span class="Constant">1</span>:num<span class="Special"> <- </span>copy <span class="Constant">0</span>
<span class="Constant">2</span>:num<span class="Special"> <- </span>copy <span class="Constant">0</span>
<span class="Constant">3</span>:num<span class="Special"> <- </span>copy <span class="Constant">0</span>
jump <span class="Constant">+target:label</span>
<span class="Constant">4</span>:num<span class="Special"> <- </span>copy <span class="Constant">0</span>
+target
<span class="Constant">5</span>:num<span class="Special"> <- </span>copy <span class="Constant">0</span>
]
<span class="traceContains">+mem: storing 0 in location 5</span>
<span class="traceAbsent">-mem: storing 0 in location 4</span>
<span class="Delimiter">:(scenario jump_fails_without_target)</span>
<span class="Special">% Hide_errors = true;</span>
<span class="muRecipe">def</span> main [
jump
]
<span class="traceContains">+error: main: 'jump' expects an ingredient but got none</span>
<span class="Delimiter">:(scenario jump_fails_without_target_2)</span>
<span class="Special">% Hide_errors = true;</span>
<span class="muRecipe">def</span> main [
jump-<span class="Normal">if</span> <span class="Constant">1</span>/<span class="Constant">true</span>
]
<span class="traceContains">+error: main: 'jump-if' expects 2 ingredients but got 1</span>
<span class="Delimiter">:(scenario recipe_fails_on_duplicate_jump_target)</span>
<span class="Special">% Hide_errors = true;</span>
<span class="muRecipe">def</span> main [
+label
<span class="Constant">1</span>:num<span class="Special"> <- </span>copy <span class="Constant">0</span>
+label
<span class="Constant">2</span>:num<span class="Special"> <- </span>copy <span class="Constant">0</span>
]
<span class="traceContains">+error: main: duplicate label '+label'</span>
<span class="Delimiter">:(scenario jump_ignores_nontarget_label)</span>
<span class="Special">% Hide_errors = true;</span>
<span class="muRecipe">def</span> main [
<span class="Comment"># first a few lines of padding to exercise the offset computation</span>
<span class="Constant">1</span>:num<span class="Special"> <- </span>copy <span class="Constant">0</span>
<span class="Constant">2</span>:num<span class="Special"> <- </span>copy <span class="Constant">0</span>
<span class="Constant">3</span>:num<span class="Special"> <- </span>copy <span class="Constant">0</span>
jump <span class="Constant">$target:label</span>
<span class="Constant">4</span>:num<span class="Special"> <- </span>copy <span class="Constant">0</span>
$target
<span class="Constant">5</span>:num<span class="Special"> <- </span>copy <span class="Constant">0</span>
]
<span class="traceContains">+error: main: can't jump to label '$target'</span>
</pre>
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