X86: Make concat_vectors combine a bit more conservative.

Per Nadav's review comments for r192866.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193252 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Jim Grosbach 2013-10-23 17:37:40 +00:00
parent 8e3851a6eb
commit 20b2774833

View File

@ -16188,6 +16188,8 @@ static SDValue PerformConcatCombine(SDNode *N, SelectionDAG &DAG,
Op0->getOpcode() == ISD::BITCAST &&
!TLI.isTypeLegal(Op0->getValueType(0)) &&
TLI.isTypeLegal(Op0->getOperand(0)->getValueType(0))) {
if (Op0->getOperand(0)->getValueType(0).isVector())
return SDValue();
SDValue Scalar = Op0->getOperand(0);
// Any legal type here will be a simple value type.
MVT SVT = Scalar->getValueType(0).getSimpleVT();
@ -16195,6 +16197,10 @@ static SDValue PerformConcatCombine(SDNode *N, SelectionDAG &DAG,
if (SVT == MVT::x86mmx)
return SDValue();
EVT NVT = MVT::getVectorVT(SVT, 2);
// If the result vector type isn't legal, this transform won't really
// help, so bail on that, too.
if (!TLI.isTypeLegal(NVT))
return SDValue();
SDLoc dl = SDLoc(N);
SDValue Res = DAG.getNode(ISD::SCALAR_TO_VECTOR, dl, NVT, Scalar);
Res = DAG.getNode(ISD::BITCAST, dl, VT, Res);