[Loop Vectorizer] Consecutive memory access - fixed and simplified

Amended consecutive memory access detection in Loop Vectorizer.
Load/Store were not handled properly without preceding GEP instruction.

Differential Revision: https://reviews.llvm.org/D20789

llvm-svn: 281853

1 files changed, 4 insertions, 4 deletions

diff --git a/llvm/lib/Analysis/LoopAccessAnalysis.cpp b/llvm/lib/Analysis/LoopAccessAnalysis.cpp
index 81d23376fdb..6cf36a82fac 100644
--- a/llvm/lib/Analysis/LoopAccessAnalysis.cpp
+++ b/llvm/lib/Analysis/LoopAccessAnalysis.cpp
@@ -887,7 +887,7 @@ static bool isNoWrapAddRec(Value *Ptr, const SCEVAddRecExpr *AR,
 /// \brief Check whether the access through \p Ptr has a constant stride.
 int64_t llvm::getPtrStride(PredicatedScalarEvolution &PSE, Value *Ptr,
                            const Loop *Lp, const ValueToValueMap &StridesMap,
-                           bool Assume) {
+                           bool Assume, bool ShouldCheckWrap) {
   Type *Ty = Ptr->getType();
   assert(Ty->isPointerTy() && "Unexpected non-ptr");
 
@@ -926,9 +926,9 @@ int64_t llvm::getPtrStride(PredicatedScalarEvolution &PSE, Value *Ptr,
   // to access the pointer value "0" which is undefined behavior in address
   // space 0, therefore we can also vectorize this case.
   bool IsInBoundsGEP = isInBoundsGep(Ptr);
-  bool IsNoWrapAddRec =
-      PSE.hasNoOverflow(Ptr, SCEVWrapPredicate::IncrementNUSW) ||
-      isNoWrapAddRec(Ptr, AR, PSE, Lp);
+  bool IsNoWrapAddRec = !ShouldCheckWrap ||
+    PSE.hasNoOverflow(Ptr, SCEVWrapPredicate::IncrementNUSW) ||
+    isNoWrapAddRec(Ptr, AR, PSE, Lp);
   bool IsInAddressSpaceZero = PtrTy->getAddressSpace() == 0;
   if (!IsNoWrapAddRec && !IsInBoundsGEP && !IsInAddressSpaceZero) {
     if (Assume) {