PGO: create metadata for switch only if it has more than one targets.

When all cases of a switch statement are dead, the weights vector only has one
element, and we will get an ssertion failure when calling createBranchWeights.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165759 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Transforms/Utils/SimplifyCFG.cpp b/lib/Transforms/Utils/SimplifyCFG.cpp
index af8d112852383141ac74909d1615957fe35b2d70..5f8953abc07ab813c60e9c0b3e5ee2749cc0511e 100644 (file)
--- a/lib/Transforms/Utils/SimplifyCFG.cpp
+++ b/lib/Transforms/Utils/SimplifyCFG.cpp
@@ -695,7 +695,7 @@ SimplifyEqualityComparisonWithOnlyPredecessor(TerminatorInst *TI,
         SI->removeCase(i);
       }
     }
-    if (HasWeight)
+    if (HasWeight && Weights.size() >= 2)
       SI->setMetadata(LLVMContext::MD_prof,
                       MDBuilder(SI->getParent()->getContext()).
                       createBranchWeights(Weights));