fix incorrect anchor

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

diff --git a/docs/WritingAnLLVMPass.html b/docs/WritingAnLLVMPass.html
index 4e754cb1a361194c36eb3e39c426805b3ac11afb..de73db3fe5c61afb045513fc21dfec5d5131380d 100644 (file)
--- a/docs/WritingAnLLVMPass.html
+++ b/docs/WritingAnLLVMPass.html
@@ -19,6 +19,7 @@
     </ul>
   <li><a href="#passtype">Pass classes and requirements</a>
      <ul>
+     <li><a href="#ImmutablePass">The <tt>ImmutablePass</tt> class</a>
      <li><a href="#Pass">The <tt>Pass</tt> class</a>
         <ul>
         <li><a href="#run">The <tt>run</tt> method</a>
@@ -365,6 +366,27 @@ optimize how passes are run, so that the resultant compiler isn't unneccesarily
 slow.<p>
 
 
+<!-- ======================================================================= -->
+</ul><table width="100%" bgcolor="#441188" border=0 cellpadding=4 cellspacing=0>
+<tr><td>&nbsp;</td><td width="100%">&nbsp; 
+<font color="#EEEEFF" face="Georgia,Palatino"><b>
+<a name="ImmutablePass">The <tt>ImmutablePass</tt> class
+</b></font></td></tr></table><ul>
+
+The most plain and boring type of pass is the "<tt><a
+href="http://llvm.cs.uiuc.edu/doxygen/structImmutablePass.html">ImmutablePass</a></tt>"
+class.  This pass type is used for passes that do not have to be run, do not
+change state, and never need to be updated.  This is not a normal type of
+transformation or analysis, but can provide information about the current
+compiler configuration.<p>
+
+Although this pass class is very infrequently used, it is important for
+providing information about the current target machine being compiled for, and
+other static information that can affect the various transformations.<p>
+
+<tt>ImmutablePass</tt>'s never invalidate other transformations, are never
+invalidated, and are never "run".<p>
+
 
 <!-- ======================================================================= -->
 </ul><table width="100%" bgcolor="#441188" border=0 cellpadding=4 cellspacing=0>
@@ -672,14 +694,14 @@ href="http://llvm.cs.uiuc.edu/doxygen/classAnalysisUsage.html">AnalysisUsage</a>
   <i>// setPreservesAll - Call this if the pass does not modify its input at all</i>
   <b>void</b> AnalysisUsage::setPreservesAll();
 
-  <i>// preservesCFG - This function should be called by the pass, iff they do not:
+  <i>// setPreservesCFG - This function should be called by the pass, iff they do not:
   //
   //  1. Add or remove basic blocks from the function
   //  2. Modify terminator instructions in any way.
   //
   //  This is automatically implied for <a href="#BasicBlockPass">BasicBlockPass</a>'s
   //</i>
-  <b>void</b> AnalysisUsage::preservesCFG();
+  <b>void</b> AnalysisUsage::setPreservesCFG();
 </pre><p>
 
 Some examples of how to use these methods are:<p>
@@ -698,7 +720,7 @@ and:<p>
 <pre>
   <i>// This example modifies the program, but does not modify the CFG</i>
   <b>void</b> <a href="http://llvm.cs.uiuc.edu/doxygen/structLICM.html">LICM</a>::getAnalysisUsage(AnalysisUsage &amp;AU) <b>const</b> {
-    AU.preservesCFG();
+    AU.setPreservesCFG();
     AU.addRequired&lt;<a href="http://llvm.cs.uiuc.edu/doxygen/classLoopInfo.html">LoopInfo</a>&gt;();
   }
 </pre><p>
@@ -1139,7 +1161,7 @@ where we are going:<p>
 <!-- _______________________________________________________________________ -->
 </ul><h4><a name="SMP"><hr size=0>Multithreaded LLVM</h4><ul>
 
-Multiple CPU machines are becoming more command and compilation can never be
+Multiple CPU machines are becoming more common and compilation can never be
 fast enough: obviously we should allow for a multithreaded compiler.  Because of
 the semantics defined for passes above (specifically they cannot maintain state
 across invocations of their <tt>run*</tt> methods), a nice clean way to
@@ -1201,6 +1223,6 @@ href="#Pass"><tt>Pass</tt></a>, only the other way around.<p>
 <address><a href="mailto:sabre@nondot.org">Chris Lattner</a></address>
 <!-- Created: Tue Aug  6 15:00:33 CDT 2002 -->
 <!-- hhmts start -->
-Last modified: Mon Sep 16 17:37:27 CDT 2002
+Last modified: Mon Oct 21 14:52:55 CDT 2002
 <!-- hhmts end -->
 </font></body></html>