Index: lib/Transforms/Instrumentation/MemorySanitizer.cpp
===================================================================
--- lib/Transforms/Instrumentation/MemorySanitizer.cpp
+++ lib/Transforms/Instrumentation/MemorySanitizer.cpp
@@ -918,9 +918,6 @@
       StoreInst *NewSI = IRB.CreateAlignedStore(Shadow, ShadowPtr, Alignment);
       LLVM_DEBUG(dbgs() << "  STORE: " << *NewSI << "\n");
 
-      if (ClCheckAccessAddress)
-        insertShadowCheck(Addr, NewSI);
-
       if (SI->isAtomic())
         SI->setOrdering(addReleaseOrdering(SI->getOrdering()));
 
@@ -1024,13 +1021,13 @@
                                InstrumentationList.size() + StoreList.size() >
                                    (unsigned)ClInstrumentationWithCallThreshold;
 
-    // Delayed instrumentation of StoreInst.
-    // This may add new checks to be inserted later.
-    materializeStores(InstrumentWithCalls);
-
     // Insert shadow value checks.
     materializeChecks(InstrumentWithCalls);
 
+    // Delayed instrumentation of StoreInst.
+    // This may not add new address checks.
+    materializeStores(InstrumentWithCalls);
+
     return true;
   }
 
@@ -1490,6 +1487,8 @@
   /// Optionally, checks that the store address is fully defined.
   void visitStoreInst(StoreInst &I) {
     StoreList.push_back(&I);
+    if (ClCheckAccessAddress)
+      insertShadowCheck(I.getPointerOperand(), &I);
   }
 
   void handleCASOrRMW(Instruction &I) {
Index: test/Instrumentation/MemorySanitizer/check_access_address.ll
===================================================================
--- test/Instrumentation/MemorySanitizer/check_access_address.ll
+++ test/Instrumentation/MemorySanitizer/check_access_address.ll
@@ -38,11 +38,14 @@
 
 ; CHECK-LABEL: @Store
 ; CHECK: load {{.*}} @__msan_param_tls
+; Shadow calculations must happen after the check.
+; CHECK-NOT: xor
 ; CHECK: icmp
 ; CHECK: br i1
 ; CHECK: <label>
 ; CHECK: call void @__msan_warning_noreturn
 ; CHECK: <label>
+; CHECK: xor
 ; CHECK: store
 ; CHECK: store i32 %x
 ; CHECK: ret void