[SelectionDAG] Generalised the CONCAT_VECTORS creation to support BUILD_VECTOR and UNDEF folding.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@258646 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Simon Pilgrim 2016-01-23 22:27:54 +00:00
parent 228d587153
commit 6130726074
2 changed files with 14 additions and 12 deletions

View File

@ -2844,18 +2844,20 @@ static SDValue FoldCONCAT_VECTORS(SDLoc DL, EVT VT, ArrayRef<SDValue> Ops,
[](SDValue Op) { return Op.isUndef(); }))
return DAG.getUNDEF(VT);
// A CONCAT_VECTOR with all operands BUILD_VECTOR can be simplified
// to one big BUILD_VECTOR.
// FIXME: Add support for UNDEF and SCALAR_TO_VECTOR as well.
if (!std::all_of(Ops.begin(), Ops.end(), [](SDValue Op) {
return Op.getOpcode() == ISD::BUILD_VECTOR;
}))
return SDValue();
// A CONCAT_VECTOR with all UNDEF/BUILD_VECTOR operands can be
// simplified to one big BUILD_VECTOR.
// FIXME: Add support for SCALAR_TO_VECTOR as well.
EVT SVT = VT.getScalarType();
SmallVector<SDValue, 16> Elts;
for (SDValue Op : Ops)
Elts.append(Op->op_begin(), Op->op_end());
for (SDValue Op : Ops) {
EVT OpVT = Op.getValueType();
if (Op.isUndef())
Elts.append(OpVT.getVectorNumElements(), DAG.getUNDEF(SVT));
else if (Op.getOpcode() == ISD::BUILD_VECTOR)
Elts.append(Op->op_begin(), Op->op_end());
else
return SDValue();
}
// BUILD_VECTOR requires all inputs to be of the same type, find the
// maximum type and extend them all.

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@ -31,8 +31,8 @@ define <4 x double> @castB(<2 x double> %m) nounwind uwtable readnone ssp {
define <4 x i64> @castC(<2 x i64> %m) nounwind uwtable readnone ssp {
; AVX1-LABEL: castC:
; AVX1: ## BB#0:
; AVX1-NEXT: vxorps %ymm1, %ymm1, %ymm1
; AVX1-NEXT: vblendps {{.*#+}} ymm0 = ymm0[0,1,2,3],ymm1[4,5,6,7]
; AVX1-NEXT: vxorpd %ymm1, %ymm1, %ymm1
; AVX1-NEXT: vblendpd {{.*#+}} ymm0 = ymm0[0,1],ymm1[2,3]
; AVX1-NEXT: retq
;
; AVX2-LABEL: castC: