LoopVectorize: Don't store a reversed value in the vectorized value map

When we store values for reversed induction stores we must not store the
reversed value in the vectorized value map. Another instruction might use this
value.

This fixes 3 test cases of PR16455.

llvm-svn: 185051

1 files changed, 4 insertions, 1 deletions

diff --git a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
index fd20c7507e3..3784b95a76b 100644
--- a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
+++ b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
@@ -1227,8 +1227,10 @@ void InnerLoopVectorizer::vectorizeMemoryInstruction(Instruction *Instr,
   if (SI) {
     assert(!Legal->isUniform(SI->getPointerOperand()) &&
            "We do not allow storing to uniform addresses");
+    // We don't want to update the value in the map as it might be used in
+    // another expression. So don't use a reference type for "StoredVal".
+    VectorParts StoredVal = getVectorValue(SI->getValueOperand());
 
-    VectorParts &StoredVal = getVectorValue(SI->getValueOperand());
     for (unsigned Part = 0; Part < UF; ++Part) {
       // Calculate the pointer for the specific unroll-part.
       Value *PartPtr = Builder.CreateGEP(Ptr, Builder.getInt32(Part * VF));
@@ -1246,6 +1248,7 @@ void InnerLoopVectorizer::vectorizeMemoryInstruction(Instruction *Instr,
       Value *VecPtr = Builder.CreateBitCast(PartPtr, DataTy->getPointerTo(AddressSpace));
       Builder.CreateStore(StoredVal[Part], VecPtr)->setAlignment(Alignment);
     }
+    return;
   }
 
   for (unsigned Part = 0; Part < UF; ++Part) {