From d6f5ae44557fbd56edee9d7129f43d71282bafde Mon Sep 17 00:00:00 2001
From: Chris Lattner <sabre@nondot.org>
Date: Mon, 30 Jan 2006 04:22:28 +0000
Subject: [PATCH] don't insert an and node if it isn't needed here, this can
 prevent folding of lowered target nodes.

llvm-svn: 25804
---
 llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
index 44ce9981a623..04fef370171e 100644
--- a/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
@@ -1284,7 +1284,9 @@ SDOperand SelectionDAGLegalize::LegalizeOp(SDOperand Op) {
       } else {
         // Make sure the condition is either zero or one.  It may have been
         // promoted from something else.
-        Tmp1 = DAG.getZeroExtendInReg(Tmp1, MVT::i1);
+        unsigned NumBits = MVT::getSizeInBits(Tmp1.getValueType());
+        if (!TLI.MaskedValueIsZero(Tmp1, (~0ULL >> (64-NumBits))^1))
+          Tmp1 = DAG.getZeroExtendInReg(Tmp1, MVT::i1);
         Result = DAG.getSelectCC(Tmp1, 
                                  DAG.getConstant(0, Tmp1.getValueType()),
                                  Tmp2, Tmp3, ISD::SETNE);