improve optimization of invoke instructions:
- simplifycfg: invoke undef/null -> unreachable
- instcombine: invoke new -> invoke expect(0, 0) (an arbitrary NOOP intrinsic; only done if the allocated memory is unused, of course)
- verifier: allow invoke of intrinsics (to make the previous step work)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159146 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/SimplifyCFGPass.cpp b/lib/Transforms/Scalar/SimplifyCFGPass.cpp
index a66b3e3..5943697 100644
--- a/lib/Transforms/Scalar/SimplifyCFGPass.cpp
+++ b/lib/Transforms/Scalar/SimplifyCFGPass.cpp
@@ -157,11 +157,16 @@
}
// Turn invokes that call 'nounwind' functions into ordinary calls.
- if (InvokeInst *II = dyn_cast<InvokeInst>(BB->getTerminator()))
- if (II->doesNotThrow()) {
+ if (InvokeInst *II = dyn_cast<InvokeInst>(BB->getTerminator())) {
+ Value *Callee = II->getCalledValue();
+ if (isa<ConstantPointerNull>(Callee) || isa<UndefValue>(Callee)) {
+ ChangeToUnreachable(II, true);
+ Changed = true;
+ } else if (II->doesNotThrow()) {
ChangeToCall(II);
Changed = true;
}
+ }
Changed |= ConstantFoldTerminator(BB, true);
for (succ_iterator SI = succ_begin(BB), SE = succ_end(BB); SI != SE; ++SI)