[llvm] r183047 - LoopVectorize: Change API call to get the backedge taken count

[Arnold Schwaighofer]

Author: arnolds
Date: Fri May 31 16:48:56 2013
New Revision: 183047

URL: http://llvm.org/viewvc/llvm-project?rev=183047&view=rev
Log:
LoopVectorize: Change API call to get the backedge taken count

Use ScalarEvolution's getBackedgeTakenCount API instead of getExitCount since
that is really what we want to know. Using the more specific getExitCount was
safe because we made sure that there is only one exiting block.

No functionality change.

Modified:
    llvm/trunk/lib/Transforms/Vectorize/LoopVectorize.cpp

Modified: llvm/trunk/lib/Transforms/Vectorize/LoopVectorize.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Vectorize/LoopVectorize.cpp?rev=183047&r1=183046&r2=183047&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Vectorize/LoopVectorize.cpp (original)
+++ llvm/trunk/lib/Transforms/Vectorize/LoopVectorize.cpp Fri May 31 16:48:56 2013
@@ -1013,7 +1013,7 @@ LoopVectorizationLegality::RuntimePointe
   const SCEV *Sc = SE->getSCEV(Ptr);
   const SCEVAddRecExpr *AR = dyn_cast<SCEVAddRecExpr>(Sc);
   assert(AR && "Invalid addrec expression");
-  const SCEV *Ex = SE->getExitCount(Lp, Lp->getLoopLatch());
+  const SCEV *Ex = SE->getBackedgeTakenCount(Lp);
   const SCEV *ScEnd = AR->evaluateAtIteration(Ex, *SE);
   Pointers.push_back(Ptr);
   Starts.push_back(AR->getStart());
@@ -1456,7 +1456,7 @@ InnerLoopVectorizer::createEmptyLoop(Loo
   Type *IdxTy = Legal->getWidestInductionType();
 
   // Find the loop boundaries.
-  const SCEV *ExitCount = SE->getExitCount(OrigLoop, OrigLoop->getLoopLatch());
+  const SCEV *ExitCount = SE->getBackedgeTakenCount(OrigLoop);
   assert(ExitCount != SE->getCouldNotCompute() && "Invalid loop count");
 
   // Get the total trip count from the count by adding 1.
@@ -2584,7 +2584,7 @@ bool LoopVectorizationLegality::canVecto
         TheLoop->getHeader()->getName() << "\n");
 
   // ScalarEvolution needs to be able to find the exit count.
-  const SCEV *ExitCount = SE->getExitCount(TheLoop, Latch);
+  const SCEV *ExitCount = SE->getBackedgeTakenCount(TheLoop);
   if (ExitCount == SE->getCouldNotCompute()) {
     DEBUG(dbgs() << "LV: SCEV could not compute the loop exit count.\n");
     return false;