From a627e26d39216febeb2ae6e2f5e722d64765df56 Mon Sep 17 00:00:00 2001 From: Dan Gohman Date: Sat, 14 Nov 2009 02:06:30 +0000 Subject: Enable the tail call optimization when the caller returns undef. llvm-svn: 88737 --- llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'llvm/lib/CodeGen') diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp index f2c623cd616..90fd95eb635 100644 --- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp @@ -4376,6 +4376,10 @@ isInTailCallPosition(const Instruction *I, Attributes CalleeRetAttr, // what the call's return type is. if (!Ret || Ret->getNumOperands() == 0) return true; + // If the return value is undef, it doesn't matter what the call's + // return type is. + if (isa(Ret->getOperand(0))) return true; + // Conservatively require the attributes of the call to match those of // the return. Ignore noalias because it doesn't affect the call sequence. unsigned CallerRetAttr = F->getAttributes().getRetAttributes(); -- cgit v1.2.3