diff --git a/lib/Transforms/Utils/SimplifyCFG.cpp b/lib/Transforms/Utils/SimplifyCFG.cpp
index ff50b12cdb3..0a458979615 100644
--- a/lib/Transforms/Utils/SimplifyCFG.cpp
+++ b/lib/Transforms/Utils/SimplifyCFG.cpp
@@ -3222,7 +3222,7 @@ static bool EliminateDeadSwitchCases(SwitchInst *SI) {
     Case.getCaseSuccessor()->removePredecessor(SI->getParent());
     SI->removeCase(Case);
   }
-  if (HasWeight) {
+  if (HasWeight && Weights.size() >= 2) {
     SmallVector<uint32_t, 8> MDWeights(Weights.begin(), Weights.end());
     SI->setMetadata(LLVMContext::MD_prof,
                     MDBuilder(SI->getParent()->getContext()).
diff --git a/test/Transforms/SimplifyCFG/preserve-branchweights.ll b/test/Transforms/SimplifyCFG/preserve-branchweights.ll
index 3c0bfebbd56..67f5636573d 100644
--- a/test/Transforms/SimplifyCFG/preserve-branchweights.ll
+++ b/test/Transforms/SimplifyCFG/preserve-branchweights.ll
@@ -313,6 +313,31 @@ sw.epilog:
   ret void
 }
 
+;; If every case is dead, make sure they are all removed. This used to
+;; crash trying to merge the metadata.
+define void @test13(i32 %x) nounwind {
+entry:
+  %i = shl i32 %x, 1
+  switch i32 %i, label %a [
+    i32 21, label %b
+    i32 25, label %c
+  ], !prof !8
+; CHECK-LABEL: @test13(
+; CHECK-NEXT: entry:
+; CHECK-NEXT: call void @helper
+; CHECK-NEXT: ret void
+
+a:
+ call void @helper(i32 0) nounwind
+ ret void
+b:
+ call void @helper(i32 1) nounwind
+ ret void
+c:
+ call void @helper(i32 2) nounwind
+ ret void
+}
+
 !0 = metadata !{metadata !"branch_weights", i32 3, i32 5}
 !1 = metadata !{metadata !"branch_weights", i32 1, i32 1}
 !2 = metadata !{metadata !"branch_weights", i32 1, i32 2}