diff --git a/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp b/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp
index 589eecf0a2fe6..5fa4e352dee2a 100644
--- a/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp
@@ -3702,15 +3702,6 @@ struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> {
         continue;
       }
       unsigned Size = 0;
-      Value *Store = nullptr;
-      // Compute the Shadow for arg even if it is ByVal, because
-      // in that case getShadow() will copy the actual arg shadow to
-      // __msan_param_tls.
-      Value *ArgShadow = getShadow(A);
-      Value *ArgShadowBase = getShadowPtrForArgument(A, IRB, ArgOffset);
-      LLVM_DEBUG(dbgs() << "  Arg#" << i << ": " << *A
-                        << " Shadow: " << *ArgShadow << "\n");
-      bool ArgIsInitialized = false;
       const DataLayout &DL = F.getParent()->getDataLayout();
 
       bool ByVal = CB.paramHasAttr(i, Attribute::ByVal);
@@ -3721,6 +3712,15 @@ struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> {
         insertShadowCheck(A, &CB);
         Size = DL.getTypeAllocSize(A->getType());
       } else {
+        bool ArgIsInitialized = false;
+        Value *Store = nullptr;
+        // Compute the Shadow for arg even if it is ByVal, because
+        // in that case getShadow() will copy the actual arg shadow to
+        // __msan_param_tls.
+        Value *ArgShadow = getShadow(A);
+        Value *ArgShadowBase = getShadowPtrForArgument(A, IRB, ArgOffset);
+        LLVM_DEBUG(dbgs() << "  Arg#" << i << ": " << *A
+                          << " Shadow: " << *ArgShadow << "\n");
         if (ByVal) {
           // ByVal requires some special handling as it's too big for a single
           // load