From 75125c127d533f0da6f97619c2be4f3bee9142c4 Mon Sep 17 00:00:00 2001 From: Benjamin Kramer Date: Sat, 26 Apr 2014 13:00:53 +0000 Subject: [PATCH] Rip out X86-specific vector SDIV lowering, make the corresponding DAGCombiner transform work on vectors. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207316 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/SelectionDAG/DAGCombiner.cpp | 37 +++++++++----- lib/Target/X86/X86ISelLowering.cpp | 64 ------------------------ 2 files changed, 24 insertions(+), 77 deletions(-) diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp index 7850bc25892..8f62dc20ebb 100644 --- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -1985,27 +1985,39 @@ SDValue DAGCombiner::visitSDIV(SDNode *N) { return DAG.getNode(ISD::UDIV, SDLoc(N), N1.getValueType(), N0, N1); } + + const APInt *Divisor = nullptr; + if (N1C) { + Divisor = &N1C->getAPIntValue(); + } else if (N1.getValueType().isVector() && + N1->getOpcode() == ISD::BUILD_VECTOR) { + BuildVectorSDNode *BV = cast(N->getOperand(1)); + if (ConstantSDNode *C = BV->getConstantSplatValue()) + Divisor = &C->getAPIntValue(); + } + // fold (sdiv X, pow2) -> simple ops after legalize - if (N1C && !N1C->isNullValue() && - (N1C->getAPIntValue().isPowerOf2() || - (-N1C->getAPIntValue()).isPowerOf2())) { + if (Divisor && !!*Divisor && + (Divisor->isPowerOf2() || (-*Divisor).isPowerOf2())) { // If dividing by powers of two is cheap, then don't perform the following // fold. if (TLI.isPow2DivCheap()) return SDValue(); - unsigned lg2 = N1C->getAPIntValue().countTrailingZeros(); + unsigned lg2 = Divisor->countTrailingZeros(); // Splat the sign bit into the register - SDValue SGN = DAG.getNode(ISD::SRA, SDLoc(N), VT, N0, - DAG.getConstant(VT.getSizeInBits()-1, - getShiftAmountTy(N0.getValueType()))); + SDValue SGN = + DAG.getNode(ISD::SRA, SDLoc(N), VT, N0, + DAG.getConstant(VT.getScalarSizeInBits() - 1, + getShiftAmountTy(N0.getValueType()))); AddToWorkList(SGN.getNode()); // Add (N0 < 0) ? abs2 - 1 : 0; - SDValue SRL = DAG.getNode(ISD::SRL, SDLoc(N), VT, SGN, - DAG.getConstant(VT.getSizeInBits() - lg2, - getShiftAmountTy(SGN.getValueType()))); + SDValue SRL = + DAG.getNode(ISD::SRL, SDLoc(N), VT, SGN, + DAG.getConstant(VT.getScalarSizeInBits() - lg2, + getShiftAmountTy(SGN.getValueType()))); SDValue ADD = DAG.getNode(ISD::ADD, SDLoc(N), VT, N0, SRL); AddToWorkList(SRL.getNode()); AddToWorkList(ADD.getNode()); // Divide by pow2 @@ -2014,12 +2026,11 @@ SDValue DAGCombiner::visitSDIV(SDNode *N) { // If we're dividing by a positive value, we're done. Otherwise, we must // negate the result. - if (N1C->getAPIntValue().isNonNegative()) + if (Divisor->isNonNegative()) return SRA; AddToWorkList(SRA.getNode()); - return DAG.getNode(ISD::SUB, SDLoc(N), VT, - DAG.getConstant(0, VT), SRA); + return DAG.getNode(ISD::SUB, SDLoc(N), VT, DAG.getConstant(0, VT), SRA); } // if integer divide is expensive and we satisfy the requirements, emit an diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp index 6ce1fa75f66..9a419bb5269 100644 --- a/lib/Target/X86/X86ISelLowering.cpp +++ b/lib/Target/X86/X86ISelLowering.cpp @@ -1108,9 +1108,6 @@ void X86TargetLowering::resetOperationActions() { setOperationAction(ISD::SHL, MVT::v4i32, Custom); setOperationAction(ISD::SRA, MVT::v4i32, Custom); - - setOperationAction(ISD::SDIV, MVT::v8i16, Custom); - setOperationAction(ISD::SDIV, MVT::v4i32, Custom); } if (!TM.Options.UseSoftFloat && Subtarget->hasFp256()) { @@ -1175,8 +1172,6 @@ void X86TargetLowering::resetOperationActions() { setOperationAction(ISD::SRA, MVT::v16i16, Custom); setOperationAction(ISD::SRA, MVT::v32i8, Custom); - setOperationAction(ISD::SDIV, MVT::v16i16, Custom); - setOperationAction(ISD::SETCC, MVT::v32i8, Custom); setOperationAction(ISD::SETCC, MVT::v16i16, Custom); setOperationAction(ISD::SETCC, MVT::v8i32, Custom); @@ -1232,8 +1227,6 @@ void X86TargetLowering::resetOperationActions() { setOperationAction(ISD::UMUL_LOHI, MVT::v8i32, Custom); setOperationAction(ISD::VSELECT, MVT::v32i8, Legal); - - setOperationAction(ISD::SDIV, MVT::v8i32, Custom); } else { setOperationAction(ISD::ADD, MVT::v4i64, Custom); setOperationAction(ISD::ADD, MVT::v8i32, Custom); @@ -1342,7 +1335,6 @@ void X86TargetLowering::resetOperationActions() { setOperationAction(ISD::FNEG, MVT::v8f64, Custom); setOperationAction(ISD::FMA, MVT::v8f64, Legal); setOperationAction(ISD::FMA, MVT::v16f32, Legal); - setOperationAction(ISD::SDIV, MVT::v16i32, Custom); setOperationAction(ISD::FP_TO_SINT, MVT::i32, Legal); setOperationAction(ISD::FP_TO_UINT, MVT::i32, Legal); @@ -13193,61 +13185,6 @@ static SDValue LowerUMUL_LOHI(SDValue Op, const X86Subtarget *Subtarget, return DAG.getNode(ISD::MERGE_VALUES, dl, Op.getValueType(), Highs, Lows); } -static SDValue LowerSDIV(SDValue Op, SelectionDAG &DAG) { - MVT VT = Op.getSimpleValueType(); - MVT EltTy = VT.getVectorElementType(); - unsigned NumElts = VT.getVectorNumElements(); - SDValue N0 = Op.getOperand(0); - SDLoc dl(Op); - - // Lower sdiv X, pow2-const. - BuildVectorSDNode *C = dyn_cast(Op.getOperand(1)); - if (!C) - return SDValue(); - - APInt SplatValue, SplatUndef; - unsigned SplatBitSize; - bool HasAnyUndefs; - if (!C->isConstantSplat(SplatValue, SplatUndef, SplatBitSize, - HasAnyUndefs) || - EltTy.getSizeInBits() < SplatBitSize) - return SDValue(); - - if ((SplatValue != 0) && - (SplatValue.isPowerOf2() || (-SplatValue).isPowerOf2())) { - unsigned Lg2 = SplatValue.countTrailingZeros(); - // Splat the sign bit. - SmallVector Sz(NumElts, - DAG.getConstant(EltTy.getSizeInBits() - 1, - EltTy)); - SDValue SGN = DAG.getNode(ISD::SRA, dl, VT, N0, - DAG.getNode(ISD::BUILD_VECTOR, dl, VT, &Sz[0], - NumElts)); - // Add (N0 < 0) ? abs2 - 1 : 0; - SmallVector Amt(NumElts, - DAG.getConstant(EltTy.getSizeInBits() - Lg2, - EltTy)); - SDValue SRL = DAG.getNode(ISD::SRL, dl, VT, SGN, - DAG.getNode(ISD::BUILD_VECTOR, dl, VT, &Amt[0], - NumElts)); - SDValue ADD = DAG.getNode(ISD::ADD, dl, VT, N0, SRL); - SmallVector Lg2Amt(NumElts, DAG.getConstant(Lg2, EltTy)); - SDValue SRA = DAG.getNode(ISD::SRA, dl, VT, ADD, - DAG.getNode(ISD::BUILD_VECTOR, dl, VT, &Lg2Amt[0], - NumElts)); - - // If we're dividing by a positive value, we're done. Otherwise, we must - // negate the result. - if (SplatValue.isNonNegative()) - return SRA; - - SmallVector V(NumElts, DAG.getConstant(0, EltTy)); - SDValue Zero = DAG.getNode(ISD::BUILD_VECTOR, dl, VT, &V[0], NumElts); - return DAG.getNode(ISD::SUB, dl, VT, Zero, SRA); - } - return SDValue(); -} - static SDValue LowerScalarImmediateShift(SDValue Op, SelectionDAG &DAG, const X86Subtarget *Subtarget) { MVT VT = Op.getSimpleValueType(); @@ -14255,7 +14192,6 @@ SDValue X86TargetLowering::LowerOperation(SDValue Op, SelectionDAG &DAG) const { case ISD::SUBE: return LowerADDC_ADDE_SUBC_SUBE(Op, DAG); case ISD::ADD: return LowerADD(Op, DAG); case ISD::SUB: return LowerSUB(Op, DAG); - case ISD::SDIV: return LowerSDIV(Op, DAG); case ISD::FSINCOS: return LowerFSINCOS(Op, Subtarget, DAG); } } -- 2.34.1