Add null check for promoted direct call
Summary: We originally assume that in pgo-icp, the promoted direct call will never be null after strip point casts. However, stripPointerCasts is so smart that it could possibly return the value of the function call if it knows that the return value is always an argument. In this case, the returned value cannot cast to Instruction. In this patch, null check is added to ensure null pointer will not be accessed.
Reviewers: tejohnson, xur, davidxl, djasper
Reviewed By: tejohnson
Subscribers: llvm-commits, sanjoy
Differential Revision: https://reviews.llvm.org/D37252
llvm-svn: 312005
diff --git a/llvm/lib/Transforms/Instrumentation/IndirectCallPromotion.cpp b/llvm/lib/Transforms/Instrumentation/IndirectCallPromotion.cpp
index 1cf8090..f323e08 100644
--- a/llvm/lib/Transforms/Instrumentation/IndirectCallPromotion.cpp
+++ b/llvm/lib/Transforms/Instrumentation/IndirectCallPromotion.cpp
@@ -566,8 +566,8 @@
SmallVector<uint32_t, 1> Weights;
Weights.push_back(Count);
MDBuilder MDB(NewInst->getContext());
- dyn_cast<Instruction>(NewInst->stripPointerCasts())
- ->setMetadata(LLVMContext::MD_prof, MDB.createBranchWeights(Weights));
+ if (Instruction *DI = dyn_cast<Instruction>(NewInst->stripPointerCasts()))
+ DI->setMetadata(LLVMContext::MD_prof, MDB.createBranchWeights(Weights));
}
// Move Inst from MergeBB to IndirectCallBB.