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9 content="A glossary of terms used with the LLVM project.">
12 <div class="doc_title">The LLVM Lexicon</div>
13 <p class="doc_warning">NOTE: This document is a work in progress!</p>
14 <!-- *********************************************************************** -->
15 <div class="doc_section">Table Of Contents</div>
16 <!-- *********************************************************************** -->
17 <div class="doc_text">
19 <tr><th colspan="8"><b>- <a href="#A">A</a> -</b></th></tr>
21 <td><a href="#ADCE">ADCE</a></td>
23 <tr><th colspan="8"><b>- <a href="#B">B</a> -</b></th></tr>
25 <td><a href="#BURS">BURS</a></td>
27 <tr><th colspan="8"><b>- <a href="#C">C</a> -</b></th></tr>
29 <td><a href="#CSE">CSE</a></td>
31 <tr><th colspan="8"><b>- <a href="#D">D</a> -</b></th></tr>
33 <td><a href="#DSA">DSA</a></td>
34 <td><a href="#DSE">DSE</a></td>
36 <tr><th colspan="8"><b>- <a href="#I">I</a> -</b></th></tr>
38 <td><a href="#IPA">IPA</a></td>
39 <td><a href="#IPO">IPO</a></td>
41 <tr><th colspan="8"><b>- <a href="#L">L</a> -</b></th></tr>
43 <td><a href="#LICM">LICM</a></td>
44 <td><a href="#Load-VN">Load-VN</a></td>
46 <tr><th colspan="8"><b>- <a href="#P">P</a> -</b></th></tr>
48 <td><a href="#PRE">PRE</a></td>
50 <tr><th colspan="8"><b>- <a href="#R">R</a> -</b></th></tr>
52 <td><a href="#Reassociation">Reassociation</a></td>
54 <tr><th colspan="8"><b>- <a href="#S">S</a> -</b></th></tr>
56 <td><a href="#SCC">SCC</a></td>
57 <td><a href="#SCCP">SCCP</a></td>
58 <td><a href="#SRoA">SRoA</a></td>
59 <td><a href="#SSA">SSA</a></td>
64 <!-- *********************************************************************** -->
65 <div class="doc_section">Definitions</div>
66 <!-- *********************************************************************** -->
67 <!-- _______________________________________________________________________ -->
68 <div class="doc_subsection"><a name="A">- A -</a></div>
69 <div class="doc_text">
71 <dt><a name="ADCE"><b>ADCE</b></a></dt>
72 <dd>Aggressive Dead Code Elimination</dd>
75 <!-- _______________________________________________________________________ -->
76 <div class="doc_subsection"><a name="B">- B -</a></div>
77 <div class="doc_text">
79 <dt><a name="BURS"><b>BURS</b></a></dt>
80 <dd>Bottom Up Rewriting System - A method of instruction selection for
81 code generation. An example is the <a
82 href="http://www.program-transformation.org/Transform/BURG">BURG</a> tool.</dd>
85 <!-- _______________________________________________________________________ -->
86 <div class="doc_subsection"><a name="C">- C -</a></div>
87 <div class="doc_text">
89 <dt><a name="CSE"><b>CSE</b></a></dt>
90 <dd>Common Subexpression Elimination. An optimization that removes common
91 subexpression compuation. For example <tt>(a+b)*(a+b)</tt> has two
92 subexpressions that are the same: <tt>(a+b)</tt>. This optimization would
93 perform the addition only once and then perform the multiply (but only if
94 its compulationally correct/safe).
97 <!-- _______________________________________________________________________ -->
98 <div class="doc_subsection"><a name="D">- D -</a></div>
99 <div class="doc_text">
101 <dt><a name="DSA"><b>DSA</b></a></dt>
102 <dd>Data Structure Analysis</dd>
103 <dt><a name="DSE"><b>DSE</b></a></dt>
104 <dd>Dead Store Elimination</dd>
107 <!-- _______________________________________________________________________ -->
108 <div class="doc_subsection"><a name="I">- I -</a></div>
109 <div class="doc_text">
111 <dt><a name="IPA"><b>IPA</b></a></dt>
112 <dd>Inter-Procedural Analysis. Refers to any variety of code analysis that
113 occurs between procedures, functions or compilation units (modules).</dd>
114 <dt><a name="IPO"><b>IPO</b></a></dt>
115 <dd>Inter-Procedural Optimization. Refers to any variety of code
116 optimization that occurs between procedures, functions or compilation units
120 <!-- _______________________________________________________________________ -->
121 <div class="doc_subsection"><a name="L">- L -</a></div>
122 <div class="doc_text">
124 <dt><a name="LICM"><b>LICM</b></a></dt>
125 <dd>Loop Invariant Code Motion</dd>
126 <dt><a name="Load-VN"><b>Load-VN</b></a></dt>
127 <dd>Load Value Numbering</dd>
131 <!-- _______________________________________________________________________ -->
132 <div class="doc_subsection"><a name="P">- P -</a></div>
133 <div class="doc_text">
135 <dt><a name="PRE"><b>PRE</b></a></dt>
136 <dd>Partial Redundancy Elimination</dd>
140 <!-- _______________________________________________________________________ -->
141 <div class="doc_subsection"><a name="R">- R -</a></div>
142 <div class="doc_text">
144 <dt><a name="Reassociation"><b>Reassociation</b></a></dt> <dd>Rearranging
145 associative expressions to promote better redundancy elimination and other
146 optimization. For example, changing (A+B-A) into (B+A-A), permitting it to
147 be optimized into (B+0) then (B).
151 <!-- _______________________________________________________________________ -->
152 <div class="doc_subsection"><a name="S">- S -</a></div>
153 <div class="doc_text">
155 <dt><a name="SCC"><b>SCC</b></a></dt>
156 <dd>Strongly Connected Component</dd>
157 <dt><a name="SCCP"><b>SCCP</b></a></dt>
158 <dd>Sparse Conditional Constant Propagation</dd>
159 <dt><a name="SRoA"><b>SRoA</b></a></dt>
160 <dd>Scalar Replacement of Aggregates</dd>
161 <dt><a name="SSA"><b>SSA</b></a></dt>
162 <dd>Static Single Assignment</dd>
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