Fix an obvious typo in the loop vectorizer where the cost model uses the wrong variable. The variable BlockCost is ignored.

We don't have tests for the effect of if-conversion loops because it requires a big test (that includes if-converted loops) and it is difficult to find and balance a loop to do the right thing.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186845 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 2 insertions, 2 deletions

diff --git a/lib/Transforms/Vectorize/LoopVectorize.cpp b/lib/Transforms/Vectorize/LoopVectorize.cpp
index 4f6ab069b2..46a63c2d4b 100644
--- a/lib/Transforms/Vectorize/LoopVectorize.cpp
+++ b/lib/Transforms/Vectorize/LoopVectorize.cpp
@@ -4390,7 +4390,7 @@ unsigned LoopVectorizationCostModel::expectedCost(unsigned VF) {
         continue;
 
       unsigned C = getInstructionCost(it, VF);
-      Cost += C;
+      BlockCost += C;
       DEBUG(dbgs() << "LV: Found an estimated cost of "<< C <<" for VF " <<
             VF << " For instruction: "<< *it << "\n");
     }
@@ -4398,7 +4398,7 @@ unsigned LoopVectorizationCostModel::expectedCost(unsigned VF) {
     // We assume that if-converted blocks have a 50% chance of being executed.
     // When the code is scalar then some of the blocks are avoided due to CF.
     // When the code is vectorized we execute all code paths.
-    if (Legal->blockNeedsPredication(*bb) && VF == 1)
+    if (VF == 1 && Legal->blockNeedsPredication(*bb))
       BlockCost /= 2;
 
     Cost += BlockCost;