diff --git a/llvm/include/llvm/Analysis/MemorySSA.h b/llvm/include/llvm/Analysis/MemorySSA.h
--- a/llvm/include/llvm/Analysis/MemorySSA.h
+++ b/llvm/include/llvm/Analysis/MemorySSA.h
@@ -784,6 +784,11 @@
   /// about the beginning or end of a block.
   enum InsertionPlace { Beginning, End, BeforeTerminator };
 
+  /// Returns true if there are no memory defs in the function.
+  bool empty_defs() const {
+    return PerBlockDefs.empty();
+  }
+
 protected:
   // Used by Memory SSA dumpers and wrapper pass
   friend class MemorySSAPrinterLegacyPass;
diff --git a/llvm/lib/Transforms/Scalar/DeadStoreElimination.cpp b/llvm/lib/Transforms/Scalar/DeadStoreElimination.cpp
--- a/llvm/lib/Transforms/Scalar/DeadStoreElimination.cpp
+++ b/llvm/lib/Transforms/Scalar/DeadStoreElimination.cpp
@@ -1876,6 +1876,9 @@
                                 const LoopInfo &LI) {
   bool MadeChange = false;
 
+  if (MSSA.empty_defs())
+    return false;
+
   DSEState State(F, AA, MSSA, DT, TLI, LI);
   // For each store:
   for (unsigned I = 0; I < State.MemDefs.size(); I++) {