[CGP] avoid crashing from weightlessness
It's possible that we have branch weights with 0 values.
In that case, don't try to create an impossible BranchProbability.
llvm-svn: 268935
diff --git a/llvm/lib/CodeGen/CodeGenPrepare.cpp b/llvm/lib/CodeGen/CodeGenPrepare.cpp
index b5ffbeb..56a1639 100644
--- a/llvm/lib/CodeGen/CodeGenPrepare.cpp
+++ b/llvm/lib/CodeGen/CodeGenPrepare.cpp
@@ -4559,9 +4559,11 @@
if (SI->extractProfMetadata(TrueWeight, FalseWeight)) {
uint64_t Max = std::max(TrueWeight, FalseWeight);
uint64_t Sum = TrueWeight + FalseWeight;
- auto Probability = BranchProbability::getBranchProbability(Max, Sum);
- if (Probability > TLI->getPredictableBranchThreshold())
- return true;
+ if (Sum != 0) {
+ auto Probability = BranchProbability::getBranchProbability(Max, Sum);
+ if (Probability > TLI->getPredictableBranchThreshold())
+ return true;
+ }
}
CmpInst *Cmp = dyn_cast<CmpInst>(SI->getCondition());