mirror of
https://github.com/ganelson/inform.git
synced 2024-07-03 07:24:58 +03:00
173 lines
26 KiB
HTML
173 lines
26 KiB
HTML
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
|
|
<html>
|
|
<head>
|
|
<title>Eliminate Redundant Operations Stage</title>
|
|
<link href="../docs-assets/Breadcrumbs.css" rel="stylesheet" rev="stylesheet" type="text/css">
|
|
<meta name="viewport" content="width=device-width initial-scale=1">
|
|
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
|
|
<meta http-equiv="Content-Language" content="en-gb">
|
|
|
|
<link href="../docs-assets/Contents.css" rel="stylesheet" rev="stylesheet" type="text/css">
|
|
<link href="../docs-assets/Progress.css" rel="stylesheet" rev="stylesheet" type="text/css">
|
|
<link href="../docs-assets/Navigation.css" rel="stylesheet" rev="stylesheet" type="text/css">
|
|
<link href="../docs-assets/Fonts.css" rel="stylesheet" rev="stylesheet" type="text/css">
|
|
<link href="../docs-assets/Base.css" rel="stylesheet" rev="stylesheet" type="text/css">
|
|
<script>
|
|
function togglePopup(material_id) {
|
|
var popup = document.getElementById(material_id);
|
|
popup.classList.toggle("show");
|
|
}
|
|
</script>
|
|
|
|
<link href="../docs-assets/Popups.css" rel="stylesheet" rev="stylesheet" type="text/css">
|
|
<link href="../docs-assets/Colours.css" rel="stylesheet" rev="stylesheet" type="text/css">
|
|
|
|
</head>
|
|
<body class="commentary-font">
|
|
<nav role="navigation">
|
|
<h1><a href="../index.html">
|
|
<img src="../docs-assets/Inform.png" height=72">
|
|
</a></h1>
|
|
<ul><li><a href="../index.html">home</a></li>
|
|
</ul><h2>Compiler</h2><ul>
|
|
<li><a href="../structure.html">structure</a></li>
|
|
<li><a href="../inbuildn.html">inbuild</a></li>
|
|
<li><a href="../inform7n.html">inform7</a></li>
|
|
<li><a href="../intern.html">inter</a></li>
|
|
<li><a href="../services.html">services</a></li>
|
|
<li><a href="../secrets.html">secrets</a></li>
|
|
</ul><h2>Other Tools</h2><ul>
|
|
<li><a href="../inblorbn.html">inblorb</a></li>
|
|
<li><a href="../indocn.html">indoc</a></li>
|
|
<li><a href="../inform6.html">inform6</a></li>
|
|
<li><a href="../inpolicyn.html">inpolicy</a></li>
|
|
<li><a href="../inrtpsn.html">inrtps</a></li>
|
|
</ul><h2>Resources</h2><ul>
|
|
<li><a href="../extensions.html">extensions</a></li>
|
|
<li><a href="../kits.html">kits</a></li>
|
|
</ul><h2>Repository</h2><ul>
|
|
<li><a href="https://github.com/ganelson/inform"><img src="../docs-assets/github.png" height=18> github</a></li>
|
|
</ul><h2>Related Projects</h2><ul>
|
|
<li><a href="../../../inweb/index.html">inweb</a></li>
|
|
<li><a href="../../../intest/index.html">intest</a></li>
|
|
|
|
</ul>
|
|
</nav>
|
|
<main role="main">
|
|
<!--Weave of 'Eliminate Redundant Operations Stage' generated by Inweb-->
|
|
<div class="breadcrumbs">
|
|
<ul class="crumbs"><li><a href="../index.html">Home</a></li><li><a href="../intern.html">Inter Modules</a></li><li><a href="index.html">pipeline</a></li><li><a href="index.html#6">Chapter 6: Optimisation</a></li><li><b>Eliminate Redundant Operations Stage</b></li></ul></div>
|
|
<p class="purpose">To remove logical or arithmetic operations which neither do anything, nor have side-effects.</p>
|
|
|
|
<p class="commentary firstcommentary"><a id="SP1" class="paragraph-anchor"></a><b>§1. </b>This stage removes redundant operations, replacing each of the following
|
|
with just <span class="extract"><span class="extract-syntax">x</span></span>. This is useful mainly for the first of these cases, because
|
|
<a href="../imperative-module/2-cc.html" class="internal">Compile Conditions (in imperative)</a> has a tendency to make redundant <span class="extract"><span class="extract-syntax">OR_BIP</span></span>
|
|
operations. The other cases occur much more rarely, but we might as well
|
|
handle them too.
|
|
</p>
|
|
|
|
<pre class="displayed-code all-displayed-code code-font">
|
|
<span class="plain-syntax"> x || false</span>
|
|
<span class="plain-syntax"> x && true</span>
|
|
<span class="plain-syntax"> x + 0</span>
|
|
<span class="plain-syntax"> 0 + x</span>
|
|
<span class="plain-syntax"> x - 0</span>
|
|
<span class="plain-syntax"> x * 1</span>
|
|
<span class="plain-syntax"> 1 * x</span>
|
|
<span class="plain-syntax"> x / 1</span>
|
|
</pre>
|
|
<p class="commentary">We could also perform constant-folding here (e.g., replacing <span class="extract"><span class="extract-syntax">2+3</span></span> with <span class="extract"><span class="extract-syntax">5</span></span>),
|
|
but we would need to be careful about word size on the VM, and there's not much
|
|
gain because the next compiler after us (e.g. Inform 6) will perform its own
|
|
constant-folding anyway.
|
|
</p>
|
|
|
|
<p class="commentary">We do not replace <span class="extract"><span class="extract-syntax">x * 0</span></span> with <span class="extract"><span class="extract-syntax">0</span></span>, nor <span class="extract"><span class="extract-syntax">x && false</span></span> with <span class="extract"><span class="extract-syntax">false</span></span>, because then
|
|
any intended side-effects of evaluating <span class="extract"><span class="extract-syntax">x</span></span> would be lost.
|
|
</p>
|
|
|
|
<pre class="displayed-code all-displayed-code code-font">
|
|
<span class="reserved-syntax">void</span><span class="plain-syntax"> </span><span class="function-syntax">EliminateRedundantOperationsStage::create_pipeline_stage</span><button class="popup" onclick="togglePopup('usagePopup1')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup1">Usage of <span class="code-font"><span class="function-syntax">EliminateRedundantOperationsStage::create_pipeline_stage</span></span>:<br/>Parsing Pipelines - <a href="2-pp.html#SP10">§10</a></span></button><span class="plain-syntax">(</span><span class="reserved-syntax">void</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><a href="2-pp.html#SP3" class="function-link"><span class="function-syntax">ParsingPipelines::new_stage</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">I</span><span class="string-syntax">"eliminate-redundant-operations"</span><span class="plain-syntax">,</span>
|
|
<span class="plain-syntax"> </span><a href="6-eros.html#SP1" class="function-link"><span class="function-syntax">EliminateRedundantOperationsStage::run</span></a><span class="plain-syntax">, </span><span class="constant-syntax">NO_STAGE_ARG</span><span class="plain-syntax">, </span><span class="identifier-syntax">FALSE</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax">}</span>
|
|
|
|
<span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">redundant_operations_removed</span><span class="plain-syntax"> = </span><span class="constant-syntax">0</span><span class="plain-syntax">;</span>
|
|
<span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="function-syntax">EliminateRedundantOperationsStage::run</span><span class="plain-syntax">(</span><span class="reserved-syntax">pipeline_step</span><span class="plain-syntax"> *</span><span class="identifier-syntax">step</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">redundant_operations_removed</span><span class="plain-syntax"> = </span><span class="constant-syntax">0</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">InterTree::traverse</span><span class="plain-syntax">(</span><span class="identifier-syntax">step</span><span class="plain-syntax">-></span><span class="element-syntax">ephemera</span><span class="plain-syntax">.</span><span class="element-syntax">tree</span><span class="plain-syntax">,</span>
|
|
<span class="plain-syntax"> </span><a href="6-eros.html#SP1" class="function-link"><span class="function-syntax">EliminateRedundantOperationsStage::visitor</span></a><span class="plain-syntax">, </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">, </span><span class="identifier-syntax">NULL</span><span class="plain-syntax">, </span><span class="constant-syntax">0</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">redundant_operations_removed</span><span class="plain-syntax"> > </span><span class="constant-syntax">0</span><span class="plain-syntax">)</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">LOG</span><span class="plain-syntax">(</span><span class="string-syntax">"%d redundant operation(s) removed\n"</span><span class="plain-syntax">, </span><span class="identifier-syntax">redundant_operations_removed</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">return</span><span class="plain-syntax"> </span><span class="identifier-syntax">TRUE</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax">}</span>
|
|
|
|
<span class="reserved-syntax">void</span><span class="plain-syntax"> </span><span class="function-syntax">EliminateRedundantOperationsStage::visitor</span><span class="plain-syntax">(</span><span class="identifier-syntax">inter_tree</span><span class="plain-syntax"> *</span><span class="identifier-syntax">I</span><span class="plain-syntax">, </span><span class="identifier-syntax">inter_tree_node</span><span class="plain-syntax"> *</span><span class="identifier-syntax">P</span><span class="plain-syntax">, </span><span class="reserved-syntax">void</span><span class="plain-syntax"> *</span><span class="identifier-syntax">state</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">Inode::is</span><span class="plain-syntax">(</span><span class="identifier-syntax">P</span><span class="plain-syntax">, </span><span class="identifier-syntax">PACKAGE_IST</span><span class="plain-syntax">)) {</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">inter_package</span><span class="plain-syntax"> *</span><span class="identifier-syntax">pack</span><span class="plain-syntax"> = </span><span class="identifier-syntax">PackageInstruction::at_this_head</span><span class="plain-syntax">(</span><span class="identifier-syntax">P</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">InterPackage::is_a_function_body</span><span class="plain-syntax">(</span><span class="identifier-syntax">pack</span><span class="plain-syntax">)) {</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">inter_tree_node</span><span class="plain-syntax"> *</span><span class="identifier-syntax">D</span><span class="plain-syntax"> = </span><span class="identifier-syntax">InterPackage::head</span><span class="plain-syntax">(</span><span class="identifier-syntax">pack</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><a href="6-eros.html#SP2" class="function-link"><span class="function-syntax">EliminateRedundantOperationsStage::traverse_code_tree</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">D</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> }</span>
|
|
<span class="plain-syntax"> }</span>
|
|
<span class="plain-syntax">}</span>
|
|
</pre>
|
|
<p class="commentary firstcommentary"><a id="SP2" class="paragraph-anchor"></a><b>§2. </b><span class="extract"><span class="extract-syntax">iden[0]</span></span> and <span class="extract"><span class="extract-syntax">iden[1]</span></span> hold left and right identity elements for these binary
|
|
operations:
|
|
</p>
|
|
|
|
<pre class="displayed-code all-displayed-code code-font">
|
|
<span class="reserved-syntax">void</span><span class="plain-syntax"> </span><span class="function-syntax">EliminateRedundantOperationsStage::traverse_code_tree</span><button class="popup" onclick="togglePopup('usagePopup2')"><span class="comment-syntax">?</span><span class="popuptext" id="usagePopup2">Usage of <span class="code-font"><span class="function-syntax">EliminateRedundantOperationsStage::traverse_code_tree</span></span>:<br/><a href="6-eros.html#SP1">§1</a></span></button><span class="plain-syntax">(</span><span class="identifier-syntax">inter_tree_node</span><span class="plain-syntax"> *</span><span class="identifier-syntax">P</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">PROTECTED_LOOP_THROUGH_INTER_CHILDREN</span><span class="plain-syntax">(</span><span class="identifier-syntax">F</span><span class="plain-syntax">, </span><span class="identifier-syntax">P</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><a href="6-eros.html#SP2" class="function-link"><span class="function-syntax">EliminateRedundantOperationsStage::traverse_code_tree</span></a><span class="plain-syntax">(</span><span class="identifier-syntax">F</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> }</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">PROTECTED_LOOP_THROUGH_INTER_CHILDREN</span><span class="plain-syntax">(</span><span class="identifier-syntax">F</span><span class="plain-syntax">, </span><span class="identifier-syntax">P</span><span class="plain-syntax">) {</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">iden</span><span class="plain-syntax">[2] = { -1, -1 };</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> ((</span><span class="identifier-syntax">Inode::is</span><span class="plain-syntax">(</span><span class="identifier-syntax">F</span><span class="plain-syntax">, </span><span class="identifier-syntax">INV_IST</span><span class="plain-syntax">)) &&</span>
|
|
<span class="plain-syntax"> (</span><span class="identifier-syntax">InvInstruction::method</span><span class="plain-syntax">(</span><span class="identifier-syntax">F</span><span class="plain-syntax">) == </span><span class="identifier-syntax">PRIMITIVE_INVMETH</span><span class="plain-syntax">)) {</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">inter_symbol</span><span class="plain-syntax"> *</span><span class="identifier-syntax">prim</span><span class="plain-syntax"> = </span><span class="identifier-syntax">InvInstruction::primitive</span><span class="plain-syntax">(</span><span class="identifier-syntax">F</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">Primitives::to_BIP</span><span class="plain-syntax">(</span><span class="identifier-syntax">P</span><span class="plain-syntax">-></span><span class="element-syntax">tree</span><span class="plain-syntax">, </span><span class="identifier-syntax">prim</span><span class="plain-syntax">) == </span><span class="identifier-syntax">OR_BIP</span><span class="plain-syntax">) { </span><span class="identifier-syntax">iden</span><span class="plain-syntax">[1] = </span><span class="constant-syntax">0</span><span class="plain-syntax">; }</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">Primitives::to_BIP</span><span class="plain-syntax">(</span><span class="identifier-syntax">P</span><span class="plain-syntax">-></span><span class="element-syntax">tree</span><span class="plain-syntax">, </span><span class="identifier-syntax">prim</span><span class="plain-syntax">) == </span><span class="identifier-syntax">AND_BIP</span><span class="plain-syntax">) { </span><span class="identifier-syntax">iden</span><span class="plain-syntax">[1] = </span><span class="constant-syntax">1</span><span class="plain-syntax">; }</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">Primitives::to_BIP</span><span class="plain-syntax">(</span><span class="identifier-syntax">P</span><span class="plain-syntax">-></span><span class="element-syntax">tree</span><span class="plain-syntax">, </span><span class="identifier-syntax">prim</span><span class="plain-syntax">) == </span><span class="identifier-syntax">PLUS_BIP</span><span class="plain-syntax">) { </span><span class="identifier-syntax">iden</span><span class="plain-syntax">[0] = </span><span class="constant-syntax">0</span><span class="plain-syntax">; </span><span class="identifier-syntax">iden</span><span class="plain-syntax">[1] = </span><span class="constant-syntax">0</span><span class="plain-syntax">; }</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">Primitives::to_BIP</span><span class="plain-syntax">(</span><span class="identifier-syntax">P</span><span class="plain-syntax">-></span><span class="element-syntax">tree</span><span class="plain-syntax">, </span><span class="identifier-syntax">prim</span><span class="plain-syntax">) == </span><span class="identifier-syntax">MINUS_BIP</span><span class="plain-syntax">) { </span><span class="identifier-syntax">iden</span><span class="plain-syntax">[1] = </span><span class="constant-syntax">0</span><span class="plain-syntax">; }</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">Primitives::to_BIP</span><span class="plain-syntax">(</span><span class="identifier-syntax">P</span><span class="plain-syntax">-></span><span class="element-syntax">tree</span><span class="plain-syntax">, </span><span class="identifier-syntax">prim</span><span class="plain-syntax">) == </span><span class="identifier-syntax">TIMES_BIP</span><span class="plain-syntax">) { </span><span class="identifier-syntax">iden</span><span class="plain-syntax">[0] = </span><span class="constant-syntax">1</span><span class="plain-syntax">; </span><span class="identifier-syntax">iden</span><span class="plain-syntax">[1] = </span><span class="constant-syntax">1</span><span class="plain-syntax">; }</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> (</span><span class="identifier-syntax">Primitives::to_BIP</span><span class="plain-syntax">(</span><span class="identifier-syntax">P</span><span class="plain-syntax">-></span><span class="element-syntax">tree</span><span class="plain-syntax">, </span><span class="identifier-syntax">prim</span><span class="plain-syntax">) == </span><span class="identifier-syntax">DIVIDE_BIP</span><span class="plain-syntax">) { </span><span class="identifier-syntax">iden</span><span class="plain-syntax">[1] = </span><span class="constant-syntax">1</span><span class="plain-syntax">; }</span>
|
|
<span class="plain-syntax"> }</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> ((</span><span class="identifier-syntax">iden</span><span class="plain-syntax">[0] >= </span><span class="constant-syntax">0</span><span class="plain-syntax">) || (</span><span class="identifier-syntax">iden</span><span class="plain-syntax">[1] >= </span><span class="constant-syntax">0</span><span class="plain-syntax">)) </span><span class="named-paragraph-container code-font"><a href="6-eros.html#SP2_1" class="named-paragraph-link"><span class="named-paragraph">An elimination candidate</span><span class="named-paragraph-number">2.1</span></a></span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> }</span>
|
|
<span class="plain-syntax">}</span>
|
|
</pre>
|
|
<p class="commentary firstcommentary"><a id="SP2_1" class="paragraph-anchor"></a><b>§2.1. </b><span class="named-paragraph-container code-font"><span class="named-paragraph-defn">An elimination candidate</span><span class="named-paragraph-number">2.1</span></span><span class="comment-syntax"> =</span>
|
|
</p>
|
|
|
|
<pre class="displayed-code all-displayed-code code-font">
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">inter_tree_node</span><span class="plain-syntax"> *</span><span class="identifier-syntax">operands</span><span class="plain-syntax">[2];</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">operands</span><span class="plain-syntax">[0] = </span><span class="identifier-syntax">InterTree::first_child</span><span class="plain-syntax">(</span><span class="identifier-syntax">F</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">operands</span><span class="plain-syntax">[1] = </span><span class="identifier-syntax">InterTree::second_child</span><span class="plain-syntax">(</span><span class="identifier-syntax">F</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> ((</span><span class="identifier-syntax">operands</span><span class="plain-syntax">[0]) && (</span><span class="identifier-syntax">operands</span><span class="plain-syntax">[1])) {</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">for</span><span class="plain-syntax"> (</span><span class="reserved-syntax">int</span><span class="plain-syntax"> </span><span class="identifier-syntax">i</span><span class="plain-syntax"> = </span><span class="constant-syntax">0</span><span class="plain-syntax">; </span><span class="identifier-syntax">i</span><span class="plain-syntax"> < </span><span class="constant-syntax">2</span><span class="plain-syntax">; </span><span class="identifier-syntax">i</span><span class="plain-syntax">++) {</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> ((</span><span class="identifier-syntax">iden</span><span class="plain-syntax">[</span><span class="identifier-syntax">i</span><span class="plain-syntax">] >= </span><span class="constant-syntax">0</span><span class="plain-syntax">) && (</span><span class="identifier-syntax">Inode::is</span><span class="plain-syntax">(</span><span class="identifier-syntax">operands</span><span class="plain-syntax">[</span><span class="identifier-syntax">i</span><span class="plain-syntax">], </span><span class="identifier-syntax">VAL_IST</span><span class="plain-syntax">))) {</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">inter_pair</span><span class="plain-syntax"> </span><span class="identifier-syntax">val</span><span class="plain-syntax"> = </span><span class="identifier-syntax">ValInstruction::value</span><span class="plain-syntax">(</span><span class="identifier-syntax">operands</span><span class="plain-syntax">[</span><span class="identifier-syntax">i</span><span class="plain-syntax">]);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">if</span><span class="plain-syntax"> ((</span><span class="identifier-syntax">InterValuePairs::is_number</span><span class="plain-syntax">(</span><span class="identifier-syntax">val</span><span class="plain-syntax">)) &&</span>
|
|
<span class="plain-syntax"> (</span><span class="identifier-syntax">InterValuePairs::to_number</span><span class="plain-syntax">(</span><span class="identifier-syntax">val</span><span class="plain-syntax">) == (</span><span class="identifier-syntax">inter_ti</span><span class="plain-syntax">) </span><span class="identifier-syntax">iden</span><span class="plain-syntax">[</span><span class="identifier-syntax">i</span><span class="plain-syntax">])) {</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">redundant_operations_removed</span><span class="plain-syntax">++;</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">NodePlacement::remove</span><span class="plain-syntax">(</span><span class="identifier-syntax">operands</span><span class="plain-syntax">[</span><span class="identifier-syntax">i</span><span class="plain-syntax">]);</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">NodePlacement::move_to</span><span class="plain-syntax">(</span><span class="identifier-syntax">operands</span><span class="plain-syntax">[1-</span><span class="identifier-syntax">i</span><span class="plain-syntax">], </span><span class="identifier-syntax">InterBookmark::immediately_after</span><span class="plain-syntax">(</span><span class="identifier-syntax">F</span><span class="plain-syntax">));</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">NodePlacement::set_levels</span><span class="plain-syntax">(</span><span class="identifier-syntax">operands</span><span class="plain-syntax">[1-</span><span class="identifier-syntax">i</span><span class="plain-syntax">], </span><span class="identifier-syntax">Inode::get_level</span><span class="plain-syntax">(</span><span class="identifier-syntax">F</span><span class="plain-syntax">));</span>
|
|
<span class="plain-syntax"> </span><span class="identifier-syntax">NodePlacement::remove</span><span class="plain-syntax">(</span><span class="identifier-syntax">F</span><span class="plain-syntax">);</span>
|
|
<span class="plain-syntax"> </span><span class="reserved-syntax">break</span><span class="plain-syntax">;</span>
|
|
<span class="plain-syntax"> }</span>
|
|
<span class="plain-syntax"> }</span>
|
|
<span class="plain-syntax"> }</span>
|
|
<span class="plain-syntax"> }</span>
|
|
</pre>
|
|
<ul class="endnotetexts"><li>This code is used in <a href="6-eros.html#SP2">§2</a>.</li></ul>
|
|
<nav role="progress"><div class="progresscontainer">
|
|
<ul class="progressbar"><li class="progressprev"><a href="6-erls.html">❮</a></li><li class="progresschapter"><a href="P-wtmd.html">P</a></li><li class="progresschapter"><a href="1-pm.html">1</a></li><li class="progresschapter"><a href="2-pp.html">2</a></li><li class="progresschapter"><a href="3-ps.html">3</a></li><li class="progresschapter"><a href="4-lbks.html">4</a></li><li class="progresschapter"><a href="5-msms.html">5</a></li><li class="progresscurrentchapter">6</li><li class="progresssection"><a href="6-erms.html">erms</a></li><li class="progresssection"><a href="6-erls.html">erls</a></li><li class="progresscurrent">eros</li><li class="progressnextoff">❯</li></ul></div>
|
|
</nav><!--End of weave-->
|
|
|
|
</main>
|
|
</body>
|
|
</html>
|
|
|