1 files changed, 8 insertions, 4 deletions
diff --git a/llvm/lib/Transforms/Utils/LoopRotationUtils.cpp b/llvm/lib/Transforms/Utils/LoopRotationUtils.cpp
index 88c4937cfe1..37389a695b4 100644
--- a/llvm/lib/Transforms/Utils/LoopRotationUtils.cpp
+++ b/llvm/lib/Transforms/Utils/LoopRotationUtils.cpp
@@ -295,7 +295,7 @@ bool LoopRotate::rotateLoop(Loop *L, bool SimplifiedLatch) {
   // Begin by walking OrigHeader and populating ValueMap with an entry for
   // each Instruction.
   BasicBlock::iterator I = OrigHeader->begin(), E = OrigHeader->end();
-  ValueToValueMapTy ValueMap;
+  ValueToValueMapTy ValueMap, ValueMapMSSA;
 
   // For PHI nodes, the value available in OldPreHeader is just the
   // incoming value from OldPreHeader.
@@ -374,6 +374,9 @@ bool LoopRotate::rotateLoop(Loop *L, bool SimplifiedLatch) {
       if (auto *II = dyn_cast<IntrinsicInst>(C))
         if (II->getIntrinsicID() == Intrinsic::assume)
           AC->registerAssumption(II);
+      // MemorySSA cares whether the cloned instruction was inserted or not, and
+      // not whether it can be remapped to a simplified value.
+      ValueMapMSSA[Inst] = C;
     }
   }
 
@@ -391,10 +394,11 @@ bool LoopRotate::rotateLoop(Loop *L, bool SimplifiedLatch) {
   LoopEntryBranch->eraseFromParent();
 
   // Update MemorySSA before the rewrite call below changes the 1:1
-  // instruction:cloned_instruction_or_value mapping in ValueMap.
+  // instruction:cloned_instruction_or_value mapping.
   if (MSSAU) {
-    ValueMap[OrigHeader] = OrigPreheader;
-    MSSAU->updateForClonedBlockIntoPred(OrigHeader, OrigPreheader, ValueMap);
+    ValueMapMSSA[OrigHeader] = OrigPreheader;
+    MSSAU->updateForClonedBlockIntoPred(OrigHeader, OrigPreheader,
+                                        ValueMapMSSA);
   }
 
   SmallVector<PHINode*, 2> InsertedPHIs;