diff options
Diffstat (limited to 'llvm/lib/Target/SystemZ/SystemZISelLowering.cpp')
| -rw-r--r-- | llvm/lib/Target/SystemZ/SystemZISelLowering.cpp | 247 |
1 files changed, 111 insertions, 136 deletions
diff --git a/llvm/lib/Target/SystemZ/SystemZISelLowering.cpp b/llvm/lib/Target/SystemZ/SystemZISelLowering.cpp index 310fd41354e..7012d9a243f 100644 --- a/llvm/lib/Target/SystemZ/SystemZISelLowering.cpp +++ b/llvm/lib/Target/SystemZ/SystemZISelLowering.cpp @@ -577,26 +577,118 @@ bool SystemZTargetLowering::isFMAFasterThanFMulAndFAdd(EVT VT) const { return false; } +// Return true if the constant can be generated with a vector instruction, +// such as VGM, VGMB or VREPI. +bool SystemZVectorConstantInfo::isVectorConstantLegal( + const SystemZSubtarget &Subtarget) { + const SystemZInstrInfo *TII = + static_cast<const SystemZInstrInfo *>(Subtarget.getInstrInfo()); + if (!Subtarget.hasVector() || + (isFP128 && !Subtarget.hasVectorEnhancements1())) + return false; -// Return true if Imm can be generated with a vector instruction, such as VGM. -bool SystemZTargetLowering:: -analyzeFPImm(const APFloat &Imm, unsigned BitWidth, unsigned &Start, - unsigned &End, const SystemZInstrInfo *TII) { - APInt IntImm = Imm.bitcastToAPInt(); - if (IntImm.getActiveBits() > 64) + // Try using VECTOR GENERATE BYTE MASK. This is the architecturally- + // preferred way of creating all-zero and all-one vectors so give it + // priority over other methods below. + unsigned Mask = 0; + unsigned I = 0; + for (; I < SystemZ::VectorBytes; ++I) { + uint64_t Byte = IntBits.lshr(I * 8).trunc(8).getZExtValue(); + if (Byte == 0xff) + Mask |= 1ULL << I; + else if (Byte != 0) + break; + } + if (I == SystemZ::VectorBytes) { + Opcode = SystemZISD::BYTE_MASK; + OpVals.push_back(Mask); + VecVT = MVT::getVectorVT(MVT::getIntegerVT(8), 16); + return true; + } + + if (SplatBitSize > 64) return false; - // See if this immediate could be generated with VGM. - bool Success = TII->isRxSBGMask(IntImm.getZExtValue(), BitWidth, Start, End); - if (!Success) + auto tryValue = [&](uint64_t Value) -> bool { + // Try VECTOR REPLICATE IMMEDIATE + int64_t SignedValue = SignExtend64(Value, SplatBitSize); + if (isInt<16>(SignedValue)) { + OpVals.push_back(((unsigned) SignedValue)); + Opcode = SystemZISD::REPLICATE; + VecVT = MVT::getVectorVT(MVT::getIntegerVT(SplatBitSize), + SystemZ::VectorBits / SplatBitSize); + return true; + } + // Try VECTOR GENERATE MASK + unsigned Start, End; + if (TII->isRxSBGMask(Value, SplatBitSize, Start, End)) { + // isRxSBGMask returns the bit numbers for a full 64-bit value, with 0 + // denoting 1 << 63 and 63 denoting 1. Convert them to bit numbers for + // an SplatBitSize value, so that 0 denotes 1 << (SplatBitSize-1). + OpVals.push_back(Start - (64 - SplatBitSize)); + OpVals.push_back(End - (64 - SplatBitSize)); + Opcode = SystemZISD::ROTATE_MASK; + VecVT = MVT::getVectorVT(MVT::getIntegerVT(SplatBitSize), + SystemZ::VectorBits / SplatBitSize); + return true; + } return false; - // isRxSBGMask returns the bit numbers for a full 64-bit value, - // with 0 denoting 1 << 63 and 63 denoting 1. Convert them to - // bit numbers for an BitsPerElement value, so that 0 denotes - // 1 << (BitsPerElement-1). - Start -= 64 - BitWidth; - End -= 64 - BitWidth; - return true; + }; + + // First try assuming that any undefined bits above the highest set bit + // and below the lowest set bit are 1s. This increases the likelihood of + // being able to use a sign-extended element value in VECTOR REPLICATE + // IMMEDIATE or a wraparound mask in VECTOR GENERATE MASK. + uint64_t SplatBitsZ = SplatBits.getZExtValue(); + uint64_t SplatUndefZ = SplatUndef.getZExtValue(); + uint64_t Lower = + (SplatUndefZ & ((uint64_t(1) << findFirstSet(SplatBitsZ)) - 1)); + uint64_t Upper = + (SplatUndefZ & ~((uint64_t(1) << findLastSet(SplatBitsZ)) - 1)); + if (tryValue(SplatBitsZ | Upper | Lower)) + return true; + + // Now try assuming that any undefined bits between the first and + // last defined set bits are set. This increases the chances of + // using a non-wraparound mask. + uint64_t Middle = SplatUndefZ & ~Upper & ~Lower; + return tryValue(SplatBitsZ | Middle); +} + +SystemZVectorConstantInfo::SystemZVectorConstantInfo(APFloat FPImm) { + IntBits = FPImm.bitcastToAPInt().zextOrSelf(128); + isFP128 = (&FPImm.getSemantics() == &APFloat::IEEEquad()); + + // Find the smallest splat. + SplatBits = FPImm.bitcastToAPInt(); + unsigned Width = SplatBits.getBitWidth(); + while (Width > 8) { + unsigned HalfSize = Width / 2; + APInt HighValue = SplatBits.lshr(HalfSize).trunc(HalfSize); + APInt LowValue = SplatBits.trunc(HalfSize); + + // If the two halves do not match, stop here. + if (HighValue != LowValue || 8 > HalfSize) + break; + + SplatBits = HighValue; + Width = HalfSize; + } + SplatUndef = 0; + SplatBitSize = Width; +} + +SystemZVectorConstantInfo::SystemZVectorConstantInfo(BuildVectorSDNode *BVN) { + assert(BVN->isConstant() && "Expected a constant BUILD_VECTOR"); + bool HasAnyUndefs; + + // Get IntBits by finding the 128 bit splat. + BVN->isConstantSplat(IntBits, SplatUndef, SplatBitSize, HasAnyUndefs, 128, + true); + + // Get SplatBits by finding the 8 bit or greater splat. + BVN->isConstantSplat(SplatBits, SplatUndef, SplatBitSize, HasAnyUndefs, 8, + true); } bool SystemZTargetLowering::isFPImmLegal(const APFloat &Imm, EVT VT) const { @@ -604,12 +696,7 @@ bool SystemZTargetLowering::isFPImmLegal(const APFloat &Imm, EVT VT) const { if (Imm.isZero() || Imm.isNegZero()) return true; - if (!Subtarget.hasVector()) - return false; - const SystemZInstrInfo *TII = - static_cast<const SystemZInstrInfo *>(Subtarget.getInstrInfo()); - unsigned Start, End; - return analyzeFPImm(Imm, VT.getSizeInBits(), Start, End, TII); + return SystemZVectorConstantInfo(Imm).isVectorConstantLegal(Subtarget); } bool SystemZTargetLowering::isLegalICmpImmediate(int64_t Imm) const { @@ -4289,78 +4376,6 @@ static SDValue joinDwords(SelectionDAG &DAG, const SDLoc &DL, SDValue Op0, return DAG.getNode(SystemZISD::JOIN_DWORDS, DL, MVT::v2i64, Op0, Op1); } -// Try to represent constant BUILD_VECTOR node BVN using a BYTE MASK style -// mask. Store the mask value in Mask on success. -bool SystemZTargetLowering:: -tryBuildVectorByteMask(BuildVectorSDNode *BVN, uint64_t &Mask) { - EVT ElemVT = BVN->getValueType(0).getVectorElementType(); - unsigned BytesPerElement = ElemVT.getStoreSize(); - for (unsigned I = 0, E = BVN->getNumOperands(); I != E; ++I) { - SDValue Op = BVN->getOperand(I); - if (!Op.isUndef()) { - uint64_t Value; - if (Op.getOpcode() == ISD::Constant) - Value = cast<ConstantSDNode>(Op)->getZExtValue(); - else if (Op.getOpcode() == ISD::ConstantFP) - Value = (cast<ConstantFPSDNode>(Op)->getValueAPF().bitcastToAPInt() - .getZExtValue()); - else - return false; - for (unsigned J = 0; J < BytesPerElement; ++J) { - uint64_t Byte = (Value >> (J * 8)) & 0xff; - if (Byte == 0xff) - Mask |= 1ULL << ((E - I - 1) * BytesPerElement + J); - else if (Byte != 0) - return false; - } - } - } - return true; -} - -// Try to load a vector constant in which BitsPerElement-bit value Value -// is replicated to fill the vector. VT is the type of the resulting -// constant, which may have elements of a different size from BitsPerElement. -// Return the SDValue of the constant on success, otherwise return -// an empty value. -static SDValue tryBuildVectorReplicate(SelectionDAG &DAG, - const SystemZInstrInfo *TII, - const SDLoc &DL, EVT VT, uint64_t Value, - unsigned BitsPerElement) { - // Signed 16-bit values can be replicated using VREPI. - // Mark the constants as opaque or DAGCombiner will convert back to - // BUILD_VECTOR. - int64_t SignedValue = SignExtend64(Value, BitsPerElement); - if (isInt<16>(SignedValue)) { - MVT VecVT = MVT::getVectorVT(MVT::getIntegerVT(BitsPerElement), - SystemZ::VectorBits / BitsPerElement); - SDValue Op = DAG.getNode( - SystemZISD::REPLICATE, DL, VecVT, - DAG.getConstant(SignedValue, DL, MVT::i32, false, true /*isOpaque*/)); - return DAG.getNode(ISD::BITCAST, DL, VT, Op); - } - // See whether rotating the constant left some N places gives a value that - // is one less than a power of 2 (i.e. all zeros followed by all ones). - // If so we can use VGM. - unsigned Start, End; - if (TII->isRxSBGMask(Value, BitsPerElement, Start, End)) { - // isRxSBGMask returns the bit numbers for a full 64-bit value, - // with 0 denoting 1 << 63 and 63 denoting 1. Convert them to - // bit numbers for an BitsPerElement value, so that 0 denotes - // 1 << (BitsPerElement-1). - Start -= 64 - BitsPerElement; - End -= 64 - BitsPerElement; - MVT VecVT = MVT::getVectorVT(MVT::getIntegerVT(BitsPerElement), - SystemZ::VectorBits / BitsPerElement); - SDValue Op = DAG.getNode( - SystemZISD::ROTATE_MASK, DL, VecVT, - DAG.getConstant(Start, DL, MVT::i32, false, true /*isOpaque*/), - DAG.getConstant(End, DL, MVT::i32, false, true /*isOpaque*/)); - return DAG.getNode(ISD::BITCAST, DL, VT, Op); - } - return SDValue(); -} - // If a BUILD_VECTOR contains some EXTRACT_VECTOR_ELTs, it's usually // better to use VECTOR_SHUFFLEs on them, only using BUILD_VECTOR for // the non-EXTRACT_VECTOR_ELT elements. See if the given BUILD_VECTOR @@ -4561,55 +4576,14 @@ static SDValue buildVector(SelectionDAG &DAG, const SDLoc &DL, EVT VT, SDValue SystemZTargetLowering::lowerBUILD_VECTOR(SDValue Op, SelectionDAG &DAG) const { - const SystemZInstrInfo *TII = - static_cast<const SystemZInstrInfo *>(Subtarget.getInstrInfo()); auto *BVN = cast<BuildVectorSDNode>(Op.getNode()); SDLoc DL(Op); EVT VT = Op.getValueType(); if (BVN->isConstant()) { - // Try using VECTOR GENERATE BYTE MASK. This is the architecturally- - // preferred way of creating all-zero and all-one vectors so give it - // priority over other methods below. - uint64_t Mask; - if (ISD::isBuildVectorAllZeros(Op.getNode()) || - ISD::isBuildVectorAllOnes(Op.getNode()) || - (VT.isInteger() && tryBuildVectorByteMask(BVN, Mask))) + if (SystemZVectorConstantInfo(BVN).isVectorConstantLegal(Subtarget)) return Op; - // Try using some form of replication. - APInt SplatBits, SplatUndef; - unsigned SplatBitSize; - bool HasAnyUndefs; - if (BVN->isConstantSplat(SplatBits, SplatUndef, SplatBitSize, HasAnyUndefs, - 8, true) && - SplatBitSize <= 64) { - // First try assuming that any undefined bits above the highest set bit - // and below the lowest set bit are 1s. This increases the likelihood of - // being able to use a sign-extended element value in VECTOR REPLICATE - // IMMEDIATE or a wraparound mask in VECTOR GENERATE MASK. - uint64_t SplatBitsZ = SplatBits.getZExtValue(); - uint64_t SplatUndefZ = SplatUndef.getZExtValue(); - uint64_t Lower = (SplatUndefZ - & ((uint64_t(1) << findFirstSet(SplatBitsZ)) - 1)); - uint64_t Upper = (SplatUndefZ - & ~((uint64_t(1) << findLastSet(SplatBitsZ)) - 1)); - uint64_t Value = SplatBitsZ | Upper | Lower; - SDValue Op = tryBuildVectorReplicate(DAG, TII, DL, VT, Value, - SplatBitSize); - if (Op.getNode()) - return Op; - - // Now try assuming that any undefined bits between the first and - // last defined set bits are set. This increases the chances of - // using a non-wraparound mask. - uint64_t Middle = SplatUndefZ & ~Upper & ~Lower; - Value = SplatBitsZ | Middle; - Op = tryBuildVectorReplicate(DAG, TII, DL, VT, Value, SplatBitSize); - if (Op.getNode()) - return Op; - } - // Fall back to loading it from memory. return SDValue(); } @@ -5055,6 +5029,7 @@ const char *SystemZTargetLowering::getTargetNodeName(unsigned Opcode) const { OPCODE(TBEGIN); OPCODE(TBEGIN_NOFLOAT); OPCODE(TEND); + OPCODE(BYTE_MASK); OPCODE(ROTATE_MASK); OPCODE(REPLICATE); OPCODE(JOIN_DWORDS); |
