From ed9bab3b4da0a5c5581fdd477c19c02420dd2fc7 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. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@88737 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'lib/CodeGen') diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp index f2c623cd61..90fd95eb63 100644 --- a/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp +++ b/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 v1.2.3-70-g09d2