instcombine: disable optimization of 'invoke null/undef'. I'll move this functionality to SimplifyCFG (since we cannot make changes to the CFG here).
Fixes the crashes with the attached test case
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158951 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/InstCombine/InstCombineCalls.cpp b/lib/Transforms/InstCombine/InstCombineCalls.cpp
index b638cc2..f74cff8 100644
--- a/lib/Transforms/InstCombine/InstCombineCalls.cpp
+++ b/lib/Transforms/InstCombine/InstCombineCalls.cpp
@@ -917,24 +917,24 @@
}
if (isa<ConstantPointerNull>(Callee) || isa<UndefValue>(Callee)) {
- // This instruction is not reachable, just remove it. We insert a store to
- // undef so that we know that this code is not reachable, despite the fact
- // that we can't modify the CFG here.
- new StoreInst(ConstantInt::getTrue(Callee->getContext()),
- UndefValue::get(Type::getInt1PtrTy(Callee->getContext())),
- CS.getInstruction());
-
// If CS does not return void then replaceAllUsesWith undef.
// This allows ValueHandlers and custom metadata to adjust itself.
if (!CS.getInstruction()->getType()->isVoidTy())
ReplaceInstUsesWith(*CS.getInstruction(),
UndefValue::get(CS.getInstruction()->getType()));
- if (InvokeInst *II = dyn_cast<InvokeInst>(CS.getInstruction())) {
- // Don't break the CFG, insert a dummy cond branch.
- BranchInst::Create(II->getNormalDest(), II->getUnwindDest(),
- ConstantInt::getTrue(Callee->getContext()), II);
+ if (isa<InvokeInst>(CS.getInstruction())) {
+ // Can't remove an invoke because we cannot change the CFG.
+ return 0;
}
+
+ // This instruction is not reachable, just remove it. We insert a store to
+ // undef so that we know that this code is not reachable, despite the fact
+ // that we can't modify the CFG here.
+ new StoreInst(ConstantInt::getTrue(Callee->getContext()),
+ UndefValue::get(Type::getInt1PtrTy(Callee->getContext())),
+ CS.getInstruction());
+
return EraseInstFromFunction(*CS.getInstruction());
}