CodeGen: check return types match when emitting tail call to builtin.
We were just completely ignoring the types when determining whether we could
safely emit a libcall as a tail call. This is clearly wrong.
Theoretically, we could dig deeper looking for incidental matches (much like
the generic code in Analysis.cpp does), but it's probably not worth it for the
few libcalls that exist.
llvm-svn: 264084
diff --git a/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
index e7ab36a..40a3bdd 100644
--- a/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
@@ -2247,9 +2247,12 @@
SDValue InChain = DAG.getEntryNode();
// isTailCall may be true since the callee does not reference caller stack
- // frame. Check if it's in the right position.
+ // frame. Check if it's in the right position and that the return types match.
SDValue TCChain = InChain;
- bool isTailCall = TLI.isInTailCallPosition(DAG, Node, TCChain);
+ const Function *F = DAG.getMachineFunction().getFunction();
+ bool isTailCall =
+ TLI.isInTailCallPosition(DAG, Node, TCChain) &&
+ (RetTy == F->getReturnType() || F->getReturnType()->isVoidTy());
if (isTailCall)
InChain = TCChain;