Don't remove a landing pad if the invoke requires a table entry.
An invoke may require a table entry. For instance, when the function it calls
is expected to throw.
<rdar://problem/13360379>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@176827 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Utils/SimplifyCFG.cpp b/lib/Transforms/Utils/SimplifyCFG.cpp
index a5c5c22..681bf9c 100644
--- a/lib/Transforms/Utils/SimplifyCFG.cpp
+++ b/lib/Transforms/Utils/SimplifyCFG.cpp
@@ -2789,9 +2789,20 @@
return false;
// Turn all invokes that unwind here into calls and delete the basic block.
+ bool InvokeRequiresTableEntry = false;
+ bool Changed = false;
for (pred_iterator PI = pred_begin(BB), PE = pred_end(BB); PI != PE;) {
InvokeInst *II = cast<InvokeInst>((*PI++)->getTerminator());
+
+ if (II->hasFnAttr(Attribute::UWTable)) {
+ // Don't remove an `invoke' instruction if the ABI requires an entry into
+ // the table.
+ InvokeRequiresTableEntry = true;
+ continue;
+ }
+
SmallVector<Value*, 8> Args(II->op_begin(), II->op_end() - 3);
+
// Insert a call instruction before the invoke.
CallInst *Call = CallInst::Create(II->getCalledValue(), Args, "", II);
Call->takeName(II);
@@ -2811,11 +2822,14 @@
// Finally, delete the invoke instruction!
II->eraseFromParent();
+ Changed = true;
}
- // The landingpad is now unreachable. Zap it.
- BB->eraseFromParent();
- return true;
+ if (!InvokeRequiresTableEntry)
+ // The landingpad is now unreachable. Zap it.
+ BB->eraseFromParent();
+
+ return Changed;
}
bool SimplifyCFGOpt::SimplifyReturn(ReturnInst *RI, IRBuilder<> &Builder) {