PR9214: Convert ConstantExpr::getIndices() to return an ArrayRef, plus

[oota-llvm.git] / docs / AliasAnalysis.html

diff --git a/docs/AliasAnalysis.html b/docs/AliasAnalysis.html
index 6962a3f27d6a8d8b9fe6cce1568d9fde0df71b2d..c1603be12993a71c18d9067f6db2d0097a5cc23a 100644 (file)
--- a/docs/AliasAnalysis.html
+++ b/docs/AliasAnalysis.html
@@ -464,7 +464,7 @@ analysis results updated to reflect the changes made by these transformations.
 </p>
 
 <p>
-The <tt>AliasAnalysis</tt> interface exposes two methods which are used to
+The <tt>AliasAnalysis</tt> interface exposes four methods which are used to
 communicate program changes from the clients to the analysis implementations.
 Various alias analysis implementations should use these methods to ensure that
 their internal data structures are kept up-to-date as the program changes (for
@@ -505,6 +505,28 @@ value, then deleting the old value.  This method cannot be overridden by alias
 analysis implementations.
 </div>
 
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection">The <tt>addEscapingUse</tt> method</div>
+
+<div class="doc_text">
+<p>The <tt>addEscapingUse</tt> method is used when the uses of a pointer
+value have changed in ways that may invalidate precomputed analysis information. 
+Implementations may either use this callback to provide conservative responses
+for points whose uses have change since analysis time, or may recompute some
+or all of their internal state to continue providing accurate responses.</p>
+
+<p>In general, any new use of a pointer value is considered an escaping use,
+and must be reported through this callback, <em>except</em> for the
+uses below:</p>
+
+<ul>
+  <li>A <tt>bitcast</tt> or <tt>getelementptr</tt> of the pointer</li>
+  <li>A <tt>store</tt> through the pointer (but not a <tt>store</tt>
+      <em>of</em> the pointer)</li>
+  <li>A <tt>load</tt> through the pointer</li>
+</ul>
+</div>
+
 <!-- ======================================================================= -->
 <div class="doc_subsection">
   <a name="implefficiency">Efficiency Issues</a>
@@ -545,7 +567,7 @@ which are intended to allow a pass to keep an AliasAnalysis consistent,
 however there's no way for a pass to declare in its
 <tt>getAnalysisUsage</tt> that it does so. Some passes attempt to use
 <tt>AU.addPreserved&lt;AliasAnalysis&gt;</tt>, however this doesn't
-actually have any effect.</tt>
+actually have any effect.</p>
 
 <p><tt>AliasAnalysisCounter</tt> (<tt>-count-aa</tt>) and <tt>AliasDebugger</tt>
 (<tt>-debug-aa</tt>) are implemented as <tt>ModulePass</tt> classes, so if your
@@ -1034,7 +1056,7 @@ analysis directly.</p>
   src="http://www.w3.org/Icons/valid-html401-blue" alt="Valid HTML 4.01"></a>
 
   <a href="mailto:sabre@nondot.org">Chris Lattner</a><br>
-  <a href="http://llvm.org">LLVM Compiler Infrastructure</a><br>
+  <a href="http://llvm.org/">LLVM Compiler Infrastructure</a><br>
   Last modified: $Date$
 </address>