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

[Chris Lattner]

Changes in directory llvm/docs:

OpenProjects.html updated: 1.15 -> 1.16

---
Log message:

Update the profiling section


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Diffs of the changes:  (+23 -6)

Index: llvm/docs/OpenProjects.html
diff -u llvm/docs/OpenProjects.html:1.15 llvm/docs/OpenProjects.html:1.16
--- llvm/docs/OpenProjects.html:1.15	Sun Dec 28 17:04:17 2003
+++ llvm/docs/OpenProjects.html	Mon Mar  8 16:29:35 2004
@@ -229,11 +229,11 @@
 
 <div class="doc_text">
 
-<p>We are getting to the point where we really need a unified infrastructure for
-profile guided optimizations.  It would be wonderful to be able to write profile
-guided transformations which can be performed either at static compile time
-(compile time or offline optimization time) or at runtime in a JIT type setup.
-The LLVM transformation itself shouldn't need to know how it is being used.</p>
+<p>We now have a unified infrastructure for writing profile-guided
+transformations, which will work either at offline-compile-time or in the JIT,
+but we don't have many transformations.  We would welcome new profile-guided
+transformations as well as improvements to the current profiling system.
+</p>
 
 <p>Ideas for profile guided transformations:</p>
 
@@ -245,6 +245,23 @@
 <li>...</li>
 </ol>
 
+<p>Improvements to the existing support:</p>
+
+<ol>
+<li>The current block and edge profiling code that gets inserted is very simple
+and inefficient.  Through the use of control-dependence information, many fewer
+counters could be inserted into the code.  Also, if the execution count of a
+loop is known to be a compile-time or runtime constant, all of the counters in
+the loop could be avoided.</li>
+
+<li>You could implement one of the "static profiling" algorithms which analyze a
+piece of code an make educated guesses about the relative execution frequencies
+of various parts of the code.</li>
+
+<li>You could add path profiling support, or adapt the existing LLVM path
+profiling code to work with the generic profiling interfaces.</li>
+</ol>
+
 </div>
 
 <!-- ======================================================================= -->
@@ -302,7 +319,7 @@
   <address><a href="mailto:sabre at nondot.org">Chris Lattner</a></address>
   <a href="http://llvm.cs.uiuc.edu">The LLVM Compiler Infrastructure</a>
   <br>
-  Last modified: $Date: 2003/12/28 23:04:17 $
+  Last modified: $Date: 2004/03/08 22:29:35 $
 </div>
 
 </body>