diff options
Diffstat (limited to 'lib/CodeGen/SelectionDAG/TargetLowering.cpp')
| -rw-r--r-- | lib/CodeGen/SelectionDAG/TargetLowering.cpp | 236 |
1 files changed, 185 insertions, 51 deletions
diff --git a/lib/CodeGen/SelectionDAG/TargetLowering.cpp b/lib/CodeGen/SelectionDAG/TargetLowering.cpp index 5de0b03..b75d805 100644 --- a/lib/CodeGen/SelectionDAG/TargetLowering.cpp +++ b/lib/CodeGen/SelectionDAG/TargetLowering.cpp @@ -40,7 +40,7 @@ TargetLowering::TargetLowering(const TargetMachine &tm, : TargetLoweringBase(tm, tlof) {} const char *TargetLowering::getTargetNodeName(unsigned Opcode) const { - return NULL; + return nullptr; } /// Check whether a given call node is in tail position within its function. If @@ -103,12 +103,11 @@ TargetLowering::makeLibCall(SelectionDAG &DAG, SDValue Callee = DAG.getExternalSymbol(getLibcallName(LC), getPointerTy()); Type *RetTy = RetVT.getTypeForEVT(*DAG.getContext()); - TargetLowering:: - CallLoweringInfo CLI(DAG.getEntryNode(), RetTy, isSigned, !isSigned, false, - false, 0, getLibcallCallingConv(LC), - /*isTailCall=*/false, - doesNotReturn, isReturnValueUsed, Callee, Args, - DAG, dl); + TargetLowering::CallLoweringInfo CLI(DAG); + CLI.setDebugLoc(dl).setChain(DAG.getEntryNode()) + .setCallee(getLibcallCallingConv(LC), RetTy, Callee, &Args, 0) + .setNoReturn(doesNotReturn).setDiscardResult(!isReturnValueUsed) + .setSExtResult(isSigned).setZExtResult(!isSigned); return LowerCallTo(CLI); } @@ -226,7 +225,7 @@ unsigned TargetLowering::getJumpTableEncoding() const { return MachineJumpTableInfo::EK_BlockAddress; // In PIC mode, if the target supports a GPRel32 directive, use it. - if (getTargetMachine().getMCAsmInfo()->getGPRel32Directive() != 0) + if (getTargetMachine().getMCAsmInfo()->getGPRel32Directive() != nullptr) return MachineJumpTableInfo::EK_GPRel32BlockAddress; // Otherwise, use a label difference. @@ -386,7 +385,7 @@ bool TargetLowering::SimplifyDemandedBits(SDValue Op, if (Depth != 0) { // If not at the root, Just compute the KnownZero/KnownOne bits to // simplify things downstream. - TLO.DAG.ComputeMaskedBits(Op, KnownZero, KnownOne, Depth); + TLO.DAG.computeKnownBits(Op, KnownZero, KnownOne, Depth); return false; } // If this is the root being simplified, allow it to have multiple uses, @@ -416,7 +415,7 @@ bool TargetLowering::SimplifyDemandedBits(SDValue Op, if (ConstantSDNode *RHSC = dyn_cast<ConstantSDNode>(Op.getOperand(1))) { APInt LHSZero, LHSOne; // Do not increment Depth here; that can cause an infinite loop. - TLO.DAG.ComputeMaskedBits(Op.getOperand(0), LHSZero, LHSOne, Depth); + TLO.DAG.computeKnownBits(Op.getOperand(0), LHSZero, LHSOne, Depth); // If the LHS already has zeros where RHSC does, this and is dead. if ((LHSZero & NewMask) == (~RHSC->getAPIntValue() & NewMask)) return TLO.CombineTo(Op, Op.getOperand(0)); @@ -848,6 +847,31 @@ bool TargetLowering::SimplifyDemandedBits(SDValue Op, } break; } + case ISD::BUILD_PAIR: { + EVT HalfVT = Op.getOperand(0).getValueType(); + unsigned HalfBitWidth = HalfVT.getScalarSizeInBits(); + + APInt MaskLo = NewMask.getLoBits(HalfBitWidth).trunc(HalfBitWidth); + APInt MaskHi = NewMask.getHiBits(HalfBitWidth).trunc(HalfBitWidth); + + APInt KnownZeroLo, KnownOneLo; + APInt KnownZeroHi, KnownOneHi; + + if (SimplifyDemandedBits(Op.getOperand(0), MaskLo, KnownZeroLo, + KnownOneLo, TLO, Depth + 1)) + return true; + + if (SimplifyDemandedBits(Op.getOperand(1), MaskHi, KnownZeroHi, + KnownOneHi, TLO, Depth + 1)) + return true; + + KnownZero = KnownZeroLo.zext(BitWidth) | + KnownZeroHi.zext(BitWidth).shl(HalfBitWidth); + + KnownOne = KnownOneLo.zext(BitWidth) | + KnownOneHi.zext(BitWidth).shl(HalfBitWidth); + break; + } case ISD::ZERO_EXTEND: { unsigned OperandBitWidth = Op.getOperand(0).getValueType().getScalarType().getSizeInBits(); @@ -1040,8 +1064,8 @@ bool TargetLowering::SimplifyDemandedBits(SDValue Op, } // FALL THROUGH default: - // Just use ComputeMaskedBits to compute output bits. - TLO.DAG.ComputeMaskedBits(Op, KnownZero, KnownOne, Depth); + // Just use computeKnownBits to compute output bits. + TLO.DAG.computeKnownBits(Op, KnownZero, KnownOne, Depth); break; } @@ -1053,14 +1077,14 @@ bool TargetLowering::SimplifyDemandedBits(SDValue Op, return false; } -/// computeMaskedBitsForTargetNode - Determine which of the bits specified +/// computeKnownBitsForTargetNode - Determine which of the bits specified /// in Mask are known to be either zero or one and return them in the /// KnownZero/KnownOne bitsets. -void TargetLowering::computeMaskedBitsForTargetNode(const SDValue Op, - APInt &KnownZero, - APInt &KnownOne, - const SelectionDAG &DAG, - unsigned Depth) const { +void TargetLowering::computeKnownBitsForTargetNode(const SDValue Op, + APInt &KnownZero, + APInt &KnownOne, + const SelectionDAG &DAG, + unsigned Depth) const { assert((Op.getOpcode() >= ISD::BUILTIN_OP_END || Op.getOpcode() == ISD::INTRINSIC_WO_CHAIN || Op.getOpcode() == ISD::INTRINSIC_W_CHAIN || @@ -1074,6 +1098,7 @@ void TargetLowering::computeMaskedBitsForTargetNode(const SDValue Op, /// targets that want to expose additional information about sign bits to the /// DAG Combiner. unsigned TargetLowering::ComputeNumSignBitsForTargetNode(SDValue Op, + const SelectionDAG &, unsigned Depth) const { assert((Op.getOpcode() >= ISD::BUILTIN_OP_END || Op.getOpcode() == ISD::INTRINSIC_WO_CHAIN || @@ -1085,7 +1110,7 @@ unsigned TargetLowering::ComputeNumSignBitsForTargetNode(SDValue Op, } /// ValueHasExactlyOneBitSet - Test if the given value is known to have exactly -/// one bit set. This differs from ComputeMaskedBits in that it doesn't need to +/// one bit set. This differs from computeKnownBits in that it doesn't need to /// determine which bit is set. /// static bool ValueHasExactlyOneBitSet(SDValue Val, const SelectionDAG &DAG) { @@ -1108,11 +1133,11 @@ static bool ValueHasExactlyOneBitSet(SDValue Val, const SelectionDAG &DAG) { // More could be done here, though the above checks are enough // to handle some common cases. - // Fall back to ComputeMaskedBits to catch other known cases. + // Fall back to computeKnownBits to catch other known cases. EVT OpVT = Val.getValueType(); unsigned BitWidth = OpVT.getScalarType().getSizeInBits(); APInt KnownZero, KnownOne; - DAG.ComputeMaskedBits(Val, KnownZero, KnownOne); + DAG.computeKnownBits(Val, KnownZero, KnownOne); return (KnownZero.countPopulation() == BitWidth - 1) && (KnownOne.countPopulation() == 1); } @@ -1381,10 +1406,14 @@ TargetLowering::SimplifySetCC(EVT VT, SDValue N0, SDValue N1, EVT newVT = N0.getOperand(0).getValueType(); if (DCI.isBeforeLegalizeOps() || (isOperationLegal(ISD::SETCC, newVT) && - getCondCodeAction(Cond, newVT.getSimpleVT())==Legal)) - return DAG.getSetCC(dl, VT, N0.getOperand(0), - DAG.getConstant(C1.trunc(InSize), newVT), - Cond); + getCondCodeAction(Cond, newVT.getSimpleVT()) == Legal)) { + EVT NewSetCCVT = getSetCCResultType(*DAG.getContext(), newVT); + SDValue NewConst = DAG.getConstant(C1.trunc(InSize), newVT); + + SDValue NewSetCC = DAG.getSetCC(dl, NewSetCCVT, N0.getOperand(0), + NewConst, Cond); + return DAG.getBoolExtOrTrunc(NewSetCC, dl, VT); + } break; } default: @@ -2052,7 +2081,7 @@ const char *TargetLowering::LowerXConstraint(EVT ConstraintVT) const{ return "r"; if (ConstraintVT.isFloatingPoint()) return "f"; // works for many targets - return 0; + return nullptr; } /// LowerAsmOperandForConstraint - Lower the specified operand into the Ops @@ -2086,12 +2115,12 @@ void TargetLowering::LowerAsmOperandForConstraint(SDValue Op, if (Op.getOpcode() == ISD::ADD) { C = dyn_cast<ConstantSDNode>(Op.getOperand(1)); GA = dyn_cast<GlobalAddressSDNode>(Op.getOperand(0)); - if (C == 0 || GA == 0) { + if (!C || !GA) { C = dyn_cast<ConstantSDNode>(Op.getOperand(0)); GA = dyn_cast<GlobalAddressSDNode>(Op.getOperand(1)); } - if (C == 0 || GA == 0) - C = 0, GA = 0; + if (!C || !GA) + C = nullptr, GA = nullptr; } // If we find a valid operand, map to the TargetXXX version so that the @@ -2126,14 +2155,14 @@ std::pair<unsigned, const TargetRegisterClass*> TargetLowering:: getRegForInlineAsmConstraint(const std::string &Constraint, MVT VT) const { if (Constraint.empty() || Constraint[0] != '{') - return std::make_pair(0u, static_cast<TargetRegisterClass*>(0)); + return std::make_pair(0u, static_cast<TargetRegisterClass*>(nullptr)); assert(*(Constraint.end()-1) == '}' && "Not a brace enclosed constraint?"); // Remove the braces from around the name. StringRef RegName(Constraint.data()+1, Constraint.size()-2); std::pair<unsigned, const TargetRegisterClass*> R = - std::make_pair(0u, static_cast<const TargetRegisterClass*>(0)); + std::make_pair(0u, static_cast<const TargetRegisterClass*>(nullptr)); // Figure out which register class contains this reg. const TargetRegisterInfo *RI = getTargetMachine().getRegisterInfo(); @@ -2428,7 +2457,7 @@ TargetLowering::ConstraintWeight Value *CallOperandVal = info.CallOperandVal; // If we don't have a value, we can't do a match, // but allow it at the lowest weight. - if (CallOperandVal == NULL) + if (!CallOperandVal) return CW_Default; // Look at the constraint type. switch (*constraint) { @@ -2601,9 +2630,9 @@ SDValue TargetLowering::BuildExactSDIV(SDValue Op1, SDValue Op2, SDLoc dl, /// return a DAG expression to select that will generate the same value by /// multiplying by a magic number. See: /// <http://the.wall.riscom.net/books/proc/ppc/cwg/code2.html> -SDValue TargetLowering:: -BuildSDIV(SDNode *N, SelectionDAG &DAG, bool IsAfterLegalization, - std::vector<SDNode*> *Created) const { +SDValue TargetLowering::BuildSDIV(SDNode *N, const APInt &Divisor, + SelectionDAG &DAG, bool IsAfterLegalization, + std::vector<SDNode *> *Created) const { EVT VT = N->getValueType(0); SDLoc dl(N); @@ -2612,8 +2641,7 @@ BuildSDIV(SDNode *N, SelectionDAG &DAG, bool IsAfterLegalization, if (!isTypeLegal(VT)) return SDValue(); - APInt d = cast<ConstantSDNode>(N->getOperand(1))->getAPIntValue(); - APInt::ms magics = d.magic(); + APInt::ms magics = Divisor.magic(); // Multiply the numerator (operand 0) by the magic value // FIXME: We should support doing a MUL in a wider type @@ -2630,13 +2658,13 @@ BuildSDIV(SDNode *N, SelectionDAG &DAG, bool IsAfterLegalization, else return SDValue(); // No mulhs or equvialent // If d > 0 and m < 0, add the numerator - if (d.isStrictlyPositive() && magics.m.isNegative()) { + if (Divisor.isStrictlyPositive() && magics.m.isNegative()) { Q = DAG.getNode(ISD::ADD, dl, VT, Q, N->getOperand(0)); if (Created) Created->push_back(Q.getNode()); } // If d < 0 and m > 0, subtract the numerator. - if (d.isNegative() && magics.m.isStrictlyPositive()) { + if (Divisor.isNegative() && magics.m.isStrictlyPositive()) { Q = DAG.getNode(ISD::SUB, dl, VT, Q, N->getOperand(0)); if (Created) Created->push_back(Q.getNode()); @@ -2649,9 +2677,9 @@ BuildSDIV(SDNode *N, SelectionDAG &DAG, bool IsAfterLegalization, Created->push_back(Q.getNode()); } // Extract the sign bit and add it to the quotient - SDValue T = - DAG.getNode(ISD::SRL, dl, VT, Q, DAG.getConstant(VT.getSizeInBits()-1, - getShiftAmountTy(Q.getValueType()))); + SDValue T = DAG.getNode(ISD::SRL, dl, VT, Q, + DAG.getConstant(VT.getScalarSizeInBits() - 1, + getShiftAmountTy(Q.getValueType()))); if (Created) Created->push_back(T.getNode()); return DAG.getNode(ISD::ADD, dl, VT, Q, T); @@ -2661,9 +2689,9 @@ BuildSDIV(SDNode *N, SelectionDAG &DAG, bool IsAfterLegalization, /// return a DAG expression to select that will generate the same value by /// multiplying by a magic number. See: /// <http://the.wall.riscom.net/books/proc/ppc/cwg/code2.html> -SDValue TargetLowering:: -BuildUDIV(SDNode *N, SelectionDAG &DAG, bool IsAfterLegalization, - std::vector<SDNode*> *Created) const { +SDValue TargetLowering::BuildUDIV(SDNode *N, const APInt &Divisor, + SelectionDAG &DAG, bool IsAfterLegalization, + std::vector<SDNode *> *Created) const { EVT VT = N->getValueType(0); SDLoc dl(N); @@ -2674,22 +2702,21 @@ BuildUDIV(SDNode *N, SelectionDAG &DAG, bool IsAfterLegalization, // FIXME: We should use a narrower constant when the upper // bits are known to be zero. - const APInt &N1C = cast<ConstantSDNode>(N->getOperand(1))->getAPIntValue(); - APInt::mu magics = N1C.magicu(); + APInt::mu magics = Divisor.magicu(); SDValue Q = N->getOperand(0); // If the divisor is even, we can avoid using the expensive fixup by shifting // the divided value upfront. - if (magics.a != 0 && !N1C[0]) { - unsigned Shift = N1C.countTrailingZeros(); + if (magics.a != 0 && !Divisor[0]) { + unsigned Shift = Divisor.countTrailingZeros(); Q = DAG.getNode(ISD::SRL, dl, VT, Q, DAG.getConstant(Shift, getShiftAmountTy(Q.getValueType()))); if (Created) Created->push_back(Q.getNode()); // Get magic number for the shifted divisor. - magics = N1C.lshr(Shift).magicu(Shift); + magics = Divisor.lshr(Shift).magicu(Shift); assert(magics.a == 0 && "Should use cheap fixup now"); } @@ -2708,7 +2735,7 @@ BuildUDIV(SDNode *N, SelectionDAG &DAG, bool IsAfterLegalization, Created->push_back(Q.getNode()); if (magics.a == 0) { - assert(magics.s < N1C.getBitWidth() && + assert(magics.s < Divisor.getBitWidth() && "We shouldn't generate an undefined shift!"); return DAG.getNode(ISD::SRL, dl, VT, Q, DAG.getConstant(magics.s, getShiftAmountTy(Q.getValueType()))); @@ -2738,3 +2765,110 @@ verifyReturnAddressArgumentIsConstant(SDValue Op, SelectionDAG &DAG) const { return false; } + +//===----------------------------------------------------------------------===// +// Legalization Utilities +//===----------------------------------------------------------------------===// + +bool TargetLowering::expandMUL(SDNode *N, SDValue &Lo, SDValue &Hi, EVT HiLoVT, + SelectionDAG &DAG, SDValue LL, SDValue LH, + SDValue RL, SDValue RH) const { + EVT VT = N->getValueType(0); + SDLoc dl(N); + + bool HasMULHS = isOperationLegalOrCustom(ISD::MULHS, HiLoVT); + bool HasMULHU = isOperationLegalOrCustom(ISD::MULHU, HiLoVT); + bool HasSMUL_LOHI = isOperationLegalOrCustom(ISD::SMUL_LOHI, HiLoVT); + bool HasUMUL_LOHI = isOperationLegalOrCustom(ISD::UMUL_LOHI, HiLoVT); + if (HasMULHU || HasMULHS || HasUMUL_LOHI || HasSMUL_LOHI) { + unsigned OuterBitSize = VT.getSizeInBits(); + unsigned InnerBitSize = HiLoVT.getSizeInBits(); + unsigned LHSSB = DAG.ComputeNumSignBits(N->getOperand(0)); + unsigned RHSSB = DAG.ComputeNumSignBits(N->getOperand(1)); + + // LL, LH, RL, and RH must be either all NULL or all set to a value. + assert((LL.getNode() && LH.getNode() && RL.getNode() && RH.getNode()) || + (!LL.getNode() && !LH.getNode() && !RL.getNode() && !RH.getNode())); + + if (!LL.getNode() && !RL.getNode() && + isOperationLegalOrCustom(ISD::TRUNCATE, HiLoVT)) { + LL = DAG.getNode(ISD::TRUNCATE, dl, HiLoVT, N->getOperand(0)); + RL = DAG.getNode(ISD::TRUNCATE, dl, HiLoVT, N->getOperand(1)); + } + + if (!LL.getNode()) + return false; + + APInt HighMask = APInt::getHighBitsSet(OuterBitSize, InnerBitSize); + if (DAG.MaskedValueIsZero(N->getOperand(0), HighMask) && + DAG.MaskedValueIsZero(N->getOperand(1), HighMask)) { + // The inputs are both zero-extended. + if (HasUMUL_LOHI) { + // We can emit a umul_lohi. + Lo = DAG.getNode(ISD::UMUL_LOHI, dl, + DAG.getVTList(HiLoVT, HiLoVT), LL, RL); + Hi = SDValue(Lo.getNode(), 1); + return true; + } + if (HasMULHU) { + // We can emit a mulhu+mul. + Lo = DAG.getNode(ISD::MUL, dl, HiLoVT, LL, RL); + Hi = DAG.getNode(ISD::MULHU, dl, HiLoVT, LL, RL); + return true; + } + } + if (LHSSB > InnerBitSize && RHSSB > InnerBitSize) { + // The input values are both sign-extended. + if (HasSMUL_LOHI) { + // We can emit a smul_lohi. + Lo = DAG.getNode(ISD::SMUL_LOHI, dl, + DAG.getVTList(HiLoVT, HiLoVT), LL, RL); + Hi = SDValue(Lo.getNode(), 1); + return true; + } + if (HasMULHS) { + // We can emit a mulhs+mul. + Lo = DAG.getNode(ISD::MUL, dl, HiLoVT, LL, RL); + Hi = DAG.getNode(ISD::MULHS, dl, HiLoVT, LL, RL); + return true; + } + } + + if (!LH.getNode() && !RH.getNode() && + isOperationLegalOrCustom(ISD::SRL, VT) && + isOperationLegalOrCustom(ISD::TRUNCATE, HiLoVT)) { + unsigned ShiftAmt = VT.getSizeInBits() - HiLoVT.getSizeInBits(); + SDValue Shift = DAG.getConstant(ShiftAmt, getShiftAmountTy(VT)); + LH = DAG.getNode(ISD::SRL, dl, VT, N->getOperand(0), Shift); + LH = DAG.getNode(ISD::TRUNCATE, dl, HiLoVT, LH); + RH = DAG.getNode(ISD::SRL, dl, VT, N->getOperand(1), Shift); + RH = DAG.getNode(ISD::TRUNCATE, dl, HiLoVT, RH); + } + + if (!LH.getNode()) + return false; + + if (HasUMUL_LOHI) { + // Lo,Hi = umul LHS, RHS. + SDValue UMulLOHI = DAG.getNode(ISD::UMUL_LOHI, dl, + DAG.getVTList(HiLoVT, HiLoVT), LL, RL); + Lo = UMulLOHI; + Hi = UMulLOHI.getValue(1); + RH = DAG.getNode(ISD::MUL, dl, HiLoVT, LL, RH); + LH = DAG.getNode(ISD::MUL, dl, HiLoVT, LH, RL); + Hi = DAG.getNode(ISD::ADD, dl, HiLoVT, Hi, RH); + Hi = DAG.getNode(ISD::ADD, dl, HiLoVT, Hi, LH); + return true; + } + if (HasMULHU) { + Lo = DAG.getNode(ISD::MUL, dl, HiLoVT, LL, RL); + Hi = DAG.getNode(ISD::MULHU, dl, HiLoVT, LL, RL); + RH = DAG.getNode(ISD::MUL, dl, HiLoVT, LL, RH); + LH = DAG.getNode(ISD::MUL, dl, HiLoVT, LH, RL); + Hi = DAG.getNode(ISD::ADD, dl, HiLoVT, Hi, RH); + Hi = DAG.getNode(ISD::ADD, dl, HiLoVT, Hi, LH); + return true; + } + } + return false; +} |