return DAG.getNode(BaseOpc, DL, XLenVT, SetCC, Op.getOperand(0));
}
+static bool hasNonZeroAVL(SDValue AVL) {
+ auto *RegisterAVL = dyn_cast<RegisterSDNode>(AVL);
+ auto *ImmAVL = dyn_cast<ConstantSDNode>(AVL);
+ return (RegisterAVL && RegisterAVL->getReg() == RISCV::X0) ||
+ (ImmAVL && ImmAVL->getZExtValue() >= 1);
+}
+
/// Helper to lower a reduction sequence of the form:
/// scalar = reduce_op vec, scalar_start
static SDValue lowerReductionSeq(unsigned RVVOpcode, SDValue StartValue, SDValue Vec, SDValue Mask, SDValue VL,
SDValue InitialSplat =
lowerScalarSplat(SDValue(), StartValue, DAG.getConstant(1, DL, XLenVT),
M1VT, DL, DAG, Subtarget);
- SDValue Reduction = DAG.getNode(RVVOpcode, DL, M1VT, DAG.getUNDEF(M1VT), Vec,
+ SDValue PassThru = hasNonZeroAVL(VL) ? DAG.getUNDEF(M1VT) : InitialSplat;
+ SDValue Reduction = DAG.getNode(RVVOpcode, DL, M1VT, PassThru, Vec,
InitialSplat, Mask, VL);
return DAG.getNode(ISD::EXTRACT_VECTOR_ELT, DL, VecEltVT, Reduction,
DAG.getConstant(0, DL, XLenVT));
return SDValue();
MVT VecVT = VecEVT.getSimpleVT();
- MVT VecEltVT = VecVT.getVectorElementType();
unsigned RVVOpcode = getRVVVPReductionOp(Op.getOpcode());
- MVT ContainerVT = VecVT;
if (VecVT.isFixedLengthVector()) {
- ContainerVT = getContainerForFixedLengthVector(VecVT);
+ auto ContainerVT = getContainerForFixedLengthVector(VecVT);
Vec = convertToScalableVector(ContainerVT, Vec, DAG, Subtarget);
}
SDValue VL = Op.getOperand(3);
SDValue Mask = Op.getOperand(2);
-
- MVT M1VT = getLMUL1VT(ContainerVT);
- MVT XLenVT = Subtarget.getXLenVT();
- MVT ResVT = !VecVT.isInteger() || VecEltVT.bitsGE(XLenVT) ? VecEltVT : XLenVT;
-
- SDValue StartSplat = lowerScalarSplat(SDValue(), Op.getOperand(0),
- DAG.getConstant(1, DL, XLenVT), M1VT,
- DL, DAG, Subtarget);
- SDValue Reduction =
- DAG.getNode(RVVOpcode, DL, M1VT, StartSplat, Vec, StartSplat, Mask, VL);
- SDValue Elt0 = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, DL, ResVT, Reduction,
- DAG.getConstant(0, DL, XLenVT));
+ SDValue Elt0 = lowerReductionSeq(RVVOpcode, Op.getOperand(0), Vec, Mask, VL,
+ DL, DAG, Subtarget);
if (!VecVT.isInteger())
return Elt0;
return DAG.getSExtOrTrunc(Elt0, DL, Op.getValueType());