1 files changed, 10 insertions, 2 deletions
diff --git a/llvm/lib/Analysis/ScalarEvolutionAliasAnalysis.cpp b/llvm/lib/Analysis/ScalarEvolutionAliasAnalysis.cpp
index 2262fc9d7913..f4fa159d1ec7 100644
--- a/llvm/lib/Analysis/ScalarEvolutionAliasAnalysis.cpp
+++ b/llvm/lib/Analysis/ScalarEvolutionAliasAnalysis.cpp
@@ -23,6 +23,15 @@
 #include "llvm/InitializePasses.h"
 using namespace llvm;
 
+static bool canComputePointerDiff(ScalarEvolution &SE,
+                                  const SCEV *A, const SCEV *B) {
+  if (SE.getEffectiveSCEVType(A->getType()) !=
+      SE.getEffectiveSCEVType(B->getType()))
+    return false;
+
+  return SE.instructionCouldExistWitthOperands(A, B);
+}
+
 AliasResult SCEVAAResult::alias(const MemoryLocation &LocA,
                                 const MemoryLocation &LocB, AAQueryInfo &AAQI) {
   // If either of the memory references is empty, it doesn't matter what the
@@ -41,8 +50,7 @@ AliasResult SCEVAAResult::alias(const MemoryLocation &LocA,
 
   // If something is known about the difference between the two addresses,
   // see if it's enough to prove a NoAlias.
-  if (SE.getEffectiveSCEVType(AS->getType()) ==
-      SE.getEffectiveSCEVType(BS->getType())) {
+  if (canComputePointerDiff(SE, AS, BS)) {
     unsigned BitWidth = SE.getTypeSizeInBits(AS->getType());
     APInt ASizeInt(BitWidth, LocA.Size.hasValue()
                                  ? LocA.Size.getValue()