[llvm-commits] CVS: llvm/docs/WritingAnLLVMPass.html

[Devang Patel]

Changes in directory llvm/docs:

WritingAnLLVMPass.html updated: 1.56 -> 1.57
---
Log message:

Update doc to reflect changes I am about to install to fix PR 888: http://llvm.org/PR888 .


---
Diffs of the changes:  (+20 -1)

 WritingAnLLVMPass.html |   21 ++++++++++++++++++++-
 1 files changed, 20 insertions(+), 1 deletion(-)


Index: llvm/docs/WritingAnLLVMPass.html
diff -u llvm/docs/WritingAnLLVMPass.html:1.56 llvm/docs/WritingAnLLVMPass.html:1.57
--- llvm/docs/WritingAnLLVMPass.html:1.56	Mon Apr 16 19:17:11 2007
+++ llvm/docs/WritingAnLLVMPass.html	Tue May  1 15:55:38 2007
@@ -263,6 +263,14 @@
 time.</p>
 
 <div class="doc_code"><pre>
+     static const int ID;
+     Hello() : FunctionPass((intptr_t)&ID) {}
+</pre></div><p>
+
+<p> This declares pass identifier used by LLVM to identify pass. This allows LLVM to
+avoid using expensive C++ runtime information.</p>
+
+<div class="doc_code"><pre>
     <b>virtual bool</b> <a href="#runOnFunction">runOnFunction</a>(Function &F) {
       llvm::cerr << "<i>Hello: </i>" << F.getName() << "\n";
       <b>return false</b>;
@@ -277,6 +285,13 @@
 function.</p>
 
 <div class="doc_code"><pre>
+  const int Hello::ID = 0;
+</pre></div>
+
+<p> We initialize pass ID here. LLVM uses ID's address to identify pass so 
+initialization value is not important.</p>
+
+<div class="doc_code"><pre>
   RegisterPass<Hello> X("<i>hello</i>", "<i>Hello World Pass</i>");
 }  <i>// end of anonymous namespace</i>
 </pre></div>
@@ -295,6 +310,10 @@
 
 <b>namespace</b> {
   <b>struct Hello</b> : <b>public</b> <a href="#FunctionPass">FunctionPass</a> {
+    
+    static const int ID;
+    Hello() : FunctionPass((intptr_t)&ID) {}
+
     <b>virtual bool</b> <a href="#runOnFunction">runOnFunction</a>(Function &F) {
       llvm::cerr << "<i>Hello: </i>" << F.getName() << "\n";
       <b>return false</b>;
@@ -1788,7 +1807,7 @@
 
   <a href="mailto:sabre at nondot.org">Chris Lattner</a><br>
   <a href="http://llvm.org">The LLVM Compiler Infrastructure</a><br>
-  Last modified: $Date: 2007/04/17 00:17:11 $
+  Last modified: $Date: 2007/05/01 20:55:38 $
 </address>
 
 </body>