[llvm-commits] [llvm] r41195 - /llvm/trunk/lib/Transforms/Scalar/LoopIndexSplit.cpp

[Devang Patel]

Author: dpatel
Date: Mon Aug 20 15:49:01 2007
New Revision: 41195

URL: http://llvm.org/viewvc/llvm-project?rev=41195&view=rev
Log:

Replace indunction variable with split value in loop body.
This fixes art miscompile.

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

Modified: llvm/trunk/lib/Transforms/Scalar/LoopIndexSplit.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/LoopIndexSplit.cpp?rev=41195&r1=41194&r2=41195&view=diff

==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/LoopIndexSplit.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/LoopIndexSplit.cpp Mon Aug 20 15:49:01 2007
@@ -418,7 +418,11 @@
 
   // Update CFG.
 
-  // As a first step to break this loop, remove Latch to Header edge.
+  // Replace index variable with split value in loop body. Loop body is executed
+  // only when index variable is equal to split value.
+  IndVar->replaceAllUsesWith(SD.SplitValue);
+
+  // Remove Latch to Header edge.
   BasicBlock *Latch = L->getLoopLatch();
   BasicBlock *LatchSucc = NULL;
   BranchInst *BR = dyn_cast<BranchInst>(Latch->getTerminator());