[llvm-commits] [llvm] r122801 - /llvm/trunk/lib/Transforms/Scalar/CodeGenPrepare.cpp

[Cameron Zwarich]

Author: zwarich
Date: Mon Jan  3 22:43:31 2011
New Revision: 122801

URL: http://llvm.org/viewvc/llvm-project?rev=122801&view=rev
Log:
Avoid finding loop back edges when we are not splitting critical edges in
CodeGenPrepare (which is the default behavior).

Modified:
    llvm/trunk/lib/Transforms/Scalar/CodeGenPrepare.cpp

Modified: llvm/trunk/lib/Transforms/Scalar/CodeGenPrepare.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/CodeGenPrepare.cpp?rev=122801&r1=122800&r2=122801&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/CodeGenPrepare.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/CodeGenPrepare.cpp Mon Jan  3 22:43:31 2011
@@ -119,8 +119,10 @@
   // unconditional branch.
   EverMadeChange |= EliminateMostlyEmptyBlocks(F);
 
-  // Now find loop back edges.
-  findLoopBackEdges(F);
+  // Now find loop back edges, but only if they are being used to decide which
+  // critical edges to split.
+  if (CriticalEdgeSplit)
+    findLoopBackEdges(F);
 
   bool MadeChange = true;
   while (MadeChange) {