//===-- SIISelLowering.cpp - SI DAG Lowering Implementation ---------------===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // /// \file /// \brief Custom DAG lowering for SI // //===----------------------------------------------------------------------===// #include "SIISelLowering.h" #include "AMDGPU.h" #include "AMDGPUIntrinsicInfo.h" #include "AMDGPUSubtarget.h" #include "SIInstrInfo.h" #include "SIMachineFunctionInfo.h" #include "SIRegisterInfo.h" #include "llvm/CodeGen/CallingConvLower.h" #include "llvm/CodeGen/MachineInstrBuilder.h" #include "llvm/CodeGen/MachineRegisterInfo.h" #include "llvm/CodeGen/SelectionDAG.h" #include "llvm/IR/Function.h" #include "llvm/ADT/SmallString.h" using namespace llvm; SITargetLowering::SITargetLowering(TargetMachine &TM) : AMDGPUTargetLowering(TM) { addRegisterClass(MVT::i1, &AMDGPU::VReg_1RegClass); addRegisterClass(MVT::i64, &AMDGPU::SReg_64RegClass); addRegisterClass(MVT::v32i8, &AMDGPU::SReg_256RegClass); addRegisterClass(MVT::v64i8, &AMDGPU::SReg_512RegClass); addRegisterClass(MVT::i32, &AMDGPU::SReg_32RegClass); addRegisterClass(MVT::f32, &AMDGPU::VReg_32RegClass); addRegisterClass(MVT::f64, &AMDGPU::VReg_64RegClass); addRegisterClass(MVT::v2i32, &AMDGPU::SReg_64RegClass); addRegisterClass(MVT::v2f32, &AMDGPU::VReg_64RegClass); addRegisterClass(MVT::v4i32, &AMDGPU::SReg_128RegClass); addRegisterClass(MVT::v4f32, &AMDGPU::VReg_128RegClass); addRegisterClass(MVT::v8i32, &AMDGPU::VReg_256RegClass); addRegisterClass(MVT::v8f32, &AMDGPU::VReg_256RegClass); addRegisterClass(MVT::v16i32, &AMDGPU::VReg_512RegClass); addRegisterClass(MVT::v16f32, &AMDGPU::VReg_512RegClass); computeRegisterProperties(); // Condition Codes setCondCodeAction(ISD::SETONE, MVT::f32, Expand); setCondCodeAction(ISD::SETUEQ, MVT::f32, Expand); setCondCodeAction(ISD::SETUGE, MVT::f32, Expand); setCondCodeAction(ISD::SETUGT, MVT::f32, Expand); setCondCodeAction(ISD::SETULE, MVT::f32, Expand); setCondCodeAction(ISD::SETULT, MVT::f32, Expand); setCondCodeAction(ISD::SETONE, MVT::f64, Expand); setCondCodeAction(ISD::SETUEQ, MVT::f64, Expand); setCondCodeAction(ISD::SETUGE, MVT::f64, Expand); setCondCodeAction(ISD::SETUGT, MVT::f64, Expand); setCondCodeAction(ISD::SETULE, MVT::f64, Expand); setCondCodeAction(ISD::SETULT, MVT::f64, Expand); setOperationAction(ISD::VECTOR_SHUFFLE, MVT::v8i32, Expand); setOperationAction(ISD::VECTOR_SHUFFLE, MVT::v8f32, Expand); setOperationAction(ISD::VECTOR_SHUFFLE, MVT::v16i32, Expand); setOperationAction(ISD::VECTOR_SHUFFLE, MVT::v16f32, Expand); setOperationAction(ISD::ADD, MVT::i32, Legal); setOperationAction(ISD::ADDC, MVT::i32, Legal); setOperationAction(ISD::ADDE, MVT::i32, Legal); setOperationAction(ISD::SUBC, MVT::i32, Legal); setOperationAction(ISD::SUBE, MVT::i32, Legal); // We need to custom lower vector stores from local memory setOperationAction(ISD::LOAD, MVT::v2i32, Custom); setOperationAction(ISD::LOAD, MVT::v4i32, Custom); setOperationAction(ISD::LOAD, MVT::v8i32, Custom); setOperationAction(ISD::LOAD, MVT::v16i32, Custom); setOperationAction(ISD::STORE, MVT::v8i32, Custom); setOperationAction(ISD::STORE, MVT::v16i32, Custom); // We need to custom lower loads/stores from private memory setOperationAction(ISD::LOAD, MVT::i32, Custom); setOperationAction(ISD::LOAD, MVT::i64, Custom); setOperationAction(ISD::LOAD, MVT::v2i32, Custom); setOperationAction(ISD::LOAD, MVT::v4i32, Custom); setOperationAction(ISD::LOAD, MVT::v8i32, Custom); setOperationAction(ISD::STORE, MVT::i1, Custom); setOperationAction(ISD::STORE, MVT::i32, Custom); setOperationAction(ISD::STORE, MVT::v2i32, Custom); setOperationAction(ISD::STORE, MVT::v4i32, Custom); setOperationAction(ISD::SELECT, MVT::f32, Promote); AddPromotedToType(ISD::SELECT, MVT::f32, MVT::i32); setOperationAction(ISD::SELECT, MVT::i64, Custom); setOperationAction(ISD::SELECT, MVT::f64, Promote); AddPromotedToType(ISD::SELECT, MVT::f64, MVT::i64); setOperationAction(ISD::SELECT_CC, MVT::f32, Expand); setOperationAction(ISD::SELECT_CC, MVT::i32, Expand); setOperationAction(ISD::SELECT_CC, MVT::i64, Expand); setOperationAction(ISD::SELECT_CC, MVT::f64, Expand); setOperationAction(ISD::SETCC, MVT::v2i1, Expand); setOperationAction(ISD::SETCC, MVT::v4i1, Expand); setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i1, Legal); setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::v2i1, Custom); setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::v4i1, Custom); setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i8, Legal); setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::v2i8, Custom); setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::v4i8, Custom); setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i16, Legal); setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::v2i16, Custom); setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::v4i16, Custom); setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i32, Custom); setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::Other, Custom); setOperationAction(ISD::INTRINSIC_WO_CHAIN, MVT::Other, Custom); setOperationAction(ISD::INTRINSIC_WO_CHAIN, MVT::f32, Custom); setOperationAction(ISD::INTRINSIC_WO_CHAIN, MVT::v16i8, Custom); setOperationAction(ISD::INTRINSIC_WO_CHAIN, MVT::v4f32, Custom); setOperationAction(ISD::INTRINSIC_VOID, MVT::Other, Custom); setOperationAction(ISD::BRCOND, MVT::Other, Custom); setLoadExtAction(ISD::SEXTLOAD, MVT::i1, Promote); setLoadExtAction(ISD::SEXTLOAD, MVT::i8, Custom); setLoadExtAction(ISD::SEXTLOAD, MVT::i16, Custom); setLoadExtAction(ISD::SEXTLOAD, MVT::i32, Expand); setLoadExtAction(ISD::SEXTLOAD, MVT::v8i16, Expand); setLoadExtAction(ISD::SEXTLOAD, MVT::v16i16, Expand); setLoadExtAction(ISD::ZEXTLOAD, MVT::i1, Promote); setLoadExtAction(ISD::ZEXTLOAD, MVT::i8, Custom); setLoadExtAction(ISD::ZEXTLOAD, MVT::i16, Custom); setLoadExtAction(ISD::ZEXTLOAD, MVT::i32, Expand); setLoadExtAction(ISD::EXTLOAD, MVT::i1, Promote); setLoadExtAction(ISD::EXTLOAD, MVT::i8, Custom); setLoadExtAction(ISD::EXTLOAD, MVT::i16, Custom); setLoadExtAction(ISD::EXTLOAD, MVT::i32, Expand); setLoadExtAction(ISD::EXTLOAD, MVT::f32, Expand); setTruncStoreAction(MVT::i32, MVT::i8, Custom); setTruncStoreAction(MVT::i32, MVT::i16, Custom); setTruncStoreAction(MVT::f64, MVT::f32, Expand); setTruncStoreAction(MVT::i64, MVT::i32, Expand); setTruncStoreAction(MVT::v8i32, MVT::v8i16, Expand); setTruncStoreAction(MVT::v16i32, MVT::v16i16, Expand); setOperationAction(ISD::LOAD, MVT::i1, Custom); setOperationAction(ISD::GlobalAddress, MVT::i32, Custom); setOperationAction(ISD::GlobalAddress, MVT::i64, Custom); setOperationAction(ISD::FrameIndex, MVT::i32, Custom); // These should use UDIVREM, so set them to expand setOperationAction(ISD::UDIV, MVT::i64, Expand); setOperationAction(ISD::UREM, MVT::i64, Expand); // We only support LOAD/STORE and vector manipulation ops for vectors // with > 4 elements. MVT VecTypes[] = { MVT::v8i32, MVT::v8f32, MVT::v16i32, MVT::v16f32 }; for (MVT VT : VecTypes) { for (unsigned Op = 0; Op < ISD::BUILTIN_OP_END; ++Op) { switch(Op) { case ISD::LOAD: case ISD::STORE: case ISD::BUILD_VECTOR: case ISD::BITCAST: case ISD::EXTRACT_VECTOR_ELT: case ISD::INSERT_VECTOR_ELT: case ISD::CONCAT_VECTORS: case ISD::INSERT_SUBVECTOR: case ISD::EXTRACT_SUBVECTOR: break; default: setOperationAction(Op, VT, Expand); break; } } } for (int I = MVT::v1f64; I <= MVT::v8f64; ++I) { MVT::SimpleValueType VT = static_cast(I); setOperationAction(ISD::FTRUNC, VT, Expand); setOperationAction(ISD::FCEIL, VT, Expand); setOperationAction(ISD::FFLOOR, VT, Expand); } if (Subtarget->getGeneration() >= AMDGPUSubtarget::SEA_ISLANDS) { setOperationAction(ISD::FTRUNC, MVT::f64, Legal); setOperationAction(ISD::FCEIL, MVT::f64, Legal); setOperationAction(ISD::FFLOOR, MVT::f64, Legal); setOperationAction(ISD::FRINT, MVT::f64, Legal); } // FIXME: These should be removed and handled the same was as f32 fneg. Source // modifiers also work for the double instructions. setOperationAction(ISD::FNEG, MVT::f64, Expand); setOperationAction(ISD::FABS, MVT::f64, Expand); setTargetDAGCombine(ISD::SELECT_CC); setTargetDAGCombine(ISD::SETCC); setTargetDAGCombine(ISD::UINT_TO_FP); setSchedulingPreference(Sched::RegPressure); } //===----------------------------------------------------------------------===// // TargetLowering queries //===----------------------------------------------------------------------===// bool SITargetLowering::allowsUnalignedMemoryAccesses(EVT VT, unsigned AddrSpace, bool *IsFast) const { if (IsFast) *IsFast = false; // XXX: This depends on the address space and also we may want to revist // the alignment values we specify in the DataLayout. // TODO: I think v3i32 should allow unaligned accesses on CI with DS_READ_B96, // which isn't a simple VT. if (!VT.isSimple() || VT == MVT::Other) return false; // XXX - CI changes say "Support for unaligned memory accesses" but I don't // see what for specifically. The wording everywhere else seems to be the // same. // 3.6.4 - Operations using pairs of VGPRs (for example: double-floats) have // no alignment restrictions. if (AddrSpace == AMDGPUAS::PRIVATE_ADDRESS) { // Using any pair of GPRs should be the same as any other pair. if (IsFast) *IsFast = true; return VT.bitsGE(MVT::i64); } // XXX - The only mention I see of this in the ISA manual is for LDS direct // reads the "byte address and must be dword aligned". Is it also true for the // normal loads and stores? if (AddrSpace == AMDGPUAS::LOCAL_ADDRESS) return false; // 8.1.6 - For Dword or larger reads or writes, the two LSBs of the // byte-address are ignored, thus forcing Dword alignment. if (IsFast) *IsFast = true; return VT.bitsGT(MVT::i32); } bool SITargetLowering::shouldSplitVectorType(EVT VT) const { return VT.getScalarType().bitsLE(MVT::i16); } bool SITargetLowering::shouldConvertConstantLoadToIntImm(const APInt &Imm, Type *Ty) const { const SIInstrInfo *TII = static_cast(getTargetMachine().getInstrInfo()); return TII->isInlineConstant(Imm); } SDValue SITargetLowering::LowerParameter(SelectionDAG &DAG, EVT VT, EVT MemVT, SDLoc DL, SDValue Chain, unsigned Offset, bool Signed) const { MachineRegisterInfo &MRI = DAG.getMachineFunction().getRegInfo(); PointerType *PtrTy = PointerType::get(VT.getTypeForEVT(*DAG.getContext()), AMDGPUAS::CONSTANT_ADDRESS); SDValue BasePtr = DAG.getCopyFromReg(Chain, DL, MRI.getLiveInVirtReg(AMDGPU::SGPR0_SGPR1), MVT::i64); SDValue Ptr = DAG.getNode(ISD::ADD, DL, MVT::i64, BasePtr, DAG.getConstant(Offset, MVT::i64)); return DAG.getExtLoad(Signed ? ISD::SEXTLOAD : ISD::ZEXTLOAD, DL, VT, Chain, Ptr, MachinePointerInfo(UndefValue::get(PtrTy)), MemVT, false, false, MemVT.getSizeInBits() >> 3); } SDValue SITargetLowering::LowerFormalArguments( SDValue Chain, CallingConv::ID CallConv, bool isVarArg, const SmallVectorImpl &Ins, SDLoc DL, SelectionDAG &DAG, SmallVectorImpl &InVals) const { const TargetRegisterInfo *TRI = getTargetMachine().getRegisterInfo(); MachineFunction &MF = DAG.getMachineFunction(); FunctionType *FType = MF.getFunction()->getFunctionType(); SIMachineFunctionInfo *Info = MF.getInfo(); assert(CallConv == CallingConv::C); SmallVector Splits; uint32_t Skipped = 0; for (unsigned i = 0, e = Ins.size(), PSInputNum = 0; i != e; ++i) { const ISD::InputArg &Arg = Ins[i]; // First check if it's a PS input addr if (Info->ShaderType == ShaderType::PIXEL && !Arg.Flags.isInReg() && !Arg.Flags.isByVal()) { assert((PSInputNum <= 15) && "Too many PS inputs!"); if (!Arg.Used) { // We can savely skip PS inputs Skipped |= 1 << i; ++PSInputNum; continue; } Info->PSInputAddr |= 1 << PSInputNum++; } // Second split vertices into their elements if (Info->ShaderType != ShaderType::COMPUTE && Arg.VT.isVector()) { ISD::InputArg NewArg = Arg; NewArg.Flags.setSplit(); NewArg.VT = Arg.VT.getVectorElementType(); // We REALLY want the ORIGINAL number of vertex elements here, e.g. a // three or five element vertex only needs three or five registers, // NOT four or eigth. Type *ParamType = FType->getParamType(Arg.OrigArgIndex); unsigned NumElements = ParamType->getVectorNumElements(); for (unsigned j = 0; j != NumElements; ++j) { Splits.push_back(NewArg); NewArg.PartOffset += NewArg.VT.getStoreSize(); } } else if (Info->ShaderType != ShaderType::COMPUTE) { Splits.push_back(Arg); } } SmallVector ArgLocs; CCState CCInfo(CallConv, isVarArg, DAG.getMachineFunction(), getTargetMachine(), ArgLocs, *DAG.getContext()); // At least one interpolation mode must be enabled or else the GPU will hang. if (Info->ShaderType == ShaderType::PIXEL && (Info->PSInputAddr & 0x7F) == 0) { Info->PSInputAddr |= 1; CCInfo.AllocateReg(AMDGPU::VGPR0); CCInfo.AllocateReg(AMDGPU::VGPR1); } // The pointer to the list of arguments is stored in SGPR0, SGPR1 if (Info->ShaderType == ShaderType::COMPUTE) { CCInfo.AllocateReg(AMDGPU::SGPR0); CCInfo.AllocateReg(AMDGPU::SGPR1); MF.addLiveIn(AMDGPU::SGPR0_SGPR1, &AMDGPU::SReg_64RegClass); } if (Info->ShaderType == ShaderType::COMPUTE) { getOriginalFunctionArgs(DAG, DAG.getMachineFunction().getFunction(), Ins, Splits); } AnalyzeFormalArguments(CCInfo, Splits); for (unsigned i = 0, e = Ins.size(), ArgIdx = 0; i != e; ++i) { const ISD::InputArg &Arg = Ins[i]; if (Skipped & (1 << i)) { InVals.push_back(DAG.getUNDEF(Arg.VT)); continue; } CCValAssign &VA = ArgLocs[ArgIdx++]; EVT VT = VA.getLocVT(); if (VA.isMemLoc()) { VT = Ins[i].VT; EVT MemVT = Splits[i].VT; // The first 36 bytes of the input buffer contains information about // thread group and global sizes. SDValue Arg = LowerParameter(DAG, VT, MemVT, DL, DAG.getRoot(), 36 + VA.getLocMemOffset(), Ins[i].Flags.isSExt()); InVals.push_back(Arg); continue; } assert(VA.isRegLoc() && "Parameter must be in a register!"); unsigned Reg = VA.getLocReg(); if (VT == MVT::i64) { // For now assume it is a pointer Reg = TRI->getMatchingSuperReg(Reg, AMDGPU::sub0, &AMDGPU::SReg_64RegClass); Reg = MF.addLiveIn(Reg, &AMDGPU::SReg_64RegClass); InVals.push_back(DAG.getCopyFromReg(Chain, DL, Reg, VT)); continue; } const TargetRegisterClass *RC = TRI->getMinimalPhysRegClass(Reg, VT); Reg = MF.addLiveIn(Reg, RC); SDValue Val = DAG.getCopyFromReg(Chain, DL, Reg, VT); if (Arg.VT.isVector()) { // Build a vector from the registers Type *ParamType = FType->getParamType(Arg.OrigArgIndex); unsigned NumElements = ParamType->getVectorNumElements(); SmallVector Regs; Regs.push_back(Val); for (unsigned j = 1; j != NumElements; ++j) { Reg = ArgLocs[ArgIdx++].getLocReg(); Reg = MF.addLiveIn(Reg, RC); Regs.push_back(DAG.getCopyFromReg(Chain, DL, Reg, VT)); } // Fill up the missing vector elements NumElements = Arg.VT.getVectorNumElements() - NumElements; for (unsigned j = 0; j != NumElements; ++j) Regs.push_back(DAG.getUNDEF(VT)); InVals.push_back(DAG.getNode(ISD::BUILD_VECTOR, DL, Arg.VT, Regs)); continue; } InVals.push_back(Val); } return Chain; } MachineBasicBlock * SITargetLowering::EmitInstrWithCustomInserter( MachineInstr * MI, MachineBasicBlock * BB) const { MachineBasicBlock::iterator I = *MI; const SIInstrInfo *TII = static_cast(getTargetMachine().getInstrInfo()); MachineRegisterInfo &MRI = BB->getParent()->getRegInfo(); switch (MI->getOpcode()) { default: return AMDGPUTargetLowering::EmitInstrWithCustomInserter(MI, BB); case AMDGPU::BRANCH: return BB; case AMDGPU::SI_ADDR64_RSRC: { unsigned SuperReg = MI->getOperand(0).getReg(); unsigned SubRegLo = MRI.createVirtualRegister(&AMDGPU::SGPR_64RegClass); unsigned SubRegHi = MRI.createVirtualRegister(&AMDGPU::SGPR_64RegClass); unsigned SubRegHiHi = MRI.createVirtualRegister(&AMDGPU::SGPR_32RegClass); unsigned SubRegHiLo = MRI.createVirtualRegister(&AMDGPU::SGPR_32RegClass); BuildMI(*BB, I, MI->getDebugLoc(), TII->get(AMDGPU::S_MOV_B64), SubRegLo) .addOperand(MI->getOperand(1)); BuildMI(*BB, I, MI->getDebugLoc(), TII->get(AMDGPU::S_MOV_B32), SubRegHiLo) .addImm(0); BuildMI(*BB, I, MI->getDebugLoc(), TII->get(AMDGPU::S_MOV_B32), SubRegHiHi) .addImm(AMDGPU::RSRC_DATA_FORMAT >> 32); BuildMI(*BB, I, MI->getDebugLoc(), TII->get(AMDGPU::REG_SEQUENCE), SubRegHi) .addReg(SubRegHiLo) .addImm(AMDGPU::sub0) .addReg(SubRegHiHi) .addImm(AMDGPU::sub1); BuildMI(*BB, I, MI->getDebugLoc(), TII->get(AMDGPU::REG_SEQUENCE), SuperReg) .addReg(SubRegLo) .addImm(AMDGPU::sub0_sub1) .addReg(SubRegHi) .addImm(AMDGPU::sub2_sub3); MI->eraseFromParent(); break; } case AMDGPU::V_SUB_F64: { unsigned DestReg = MI->getOperand(0).getReg(); BuildMI(*BB, I, MI->getDebugLoc(), TII->get(AMDGPU::V_ADD_F64), DestReg) .addImm(0) // SRC0 modifiers .addReg(MI->getOperand(1).getReg()) .addImm(1) // SRC1 modifiers .addReg(MI->getOperand(2).getReg()) .addImm(0) // SRC2 modifiers .addImm(0) // src2 .addImm(0) // CLAMP .addImm(0); // OMOD MI->eraseFromParent(); break; } case AMDGPU::SI_RegisterStorePseudo: { MachineRegisterInfo &MRI = BB->getParent()->getRegInfo(); unsigned Reg = MRI.createVirtualRegister(&AMDGPU::SReg_64RegClass); MachineInstrBuilder MIB = BuildMI(*BB, I, MI->getDebugLoc(), TII->get(AMDGPU::SI_RegisterStore), Reg); for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) MIB.addOperand(MI->getOperand(i)); MI->eraseFromParent(); break; } case AMDGPU::FABS_SI: { MachineRegisterInfo &MRI = BB->getParent()->getRegInfo(); const SIInstrInfo *TII = static_cast(getTargetMachine().getInstrInfo()); unsigned Reg = MRI.createVirtualRegister(&AMDGPU::VReg_32RegClass); BuildMI(*BB, I, MI->getDebugLoc(), TII->get(AMDGPU::V_MOV_B32_e32), Reg) .addImm(0x7fffffff); BuildMI(*BB, I, MI->getDebugLoc(), TII->get(AMDGPU::V_AND_B32_e32), MI->getOperand(0).getReg()) .addReg(MI->getOperand(1).getReg()) .addReg(Reg); MI->eraseFromParent(); break; } case AMDGPU::FNEG_SI: { MachineRegisterInfo &MRI = BB->getParent()->getRegInfo(); const SIInstrInfo *TII = static_cast(getTargetMachine().getInstrInfo()); unsigned Reg = MRI.createVirtualRegister(&AMDGPU::VReg_32RegClass); BuildMI(*BB, I, MI->getDebugLoc(), TII->get(AMDGPU::V_MOV_B32_e32), Reg) .addImm(0x80000000); BuildMI(*BB, I, MI->getDebugLoc(), TII->get(AMDGPU::V_XOR_B32_e32), MI->getOperand(0).getReg()) .addReg(MI->getOperand(1).getReg()) .addReg(Reg); MI->eraseFromParent(); break; } case AMDGPU::FCLAMP_SI: { const SIInstrInfo *TII = static_cast(getTargetMachine().getInstrInfo()); BuildMI(*BB, I, MI->getDebugLoc(), TII->get(AMDGPU::V_ADD_F32_e64), MI->getOperand(0).getReg()) .addImm(0) // SRC0 modifiers .addOperand(MI->getOperand(1)) .addImm(0) // SRC1 modifiers .addImm(0) // SRC1 .addImm(1) // CLAMP .addImm(0); // OMOD MI->eraseFromParent(); } } return BB; } EVT SITargetLowering::getSetCCResultType(LLVMContext &, EVT VT) const { if (!VT.isVector()) { return MVT::i1; } return MVT::getVectorVT(MVT::i1, VT.getVectorNumElements()); } MVT SITargetLowering::getScalarShiftAmountTy(EVT VT) const { return MVT::i32; } bool SITargetLowering::isFMAFasterThanFMulAndFAdd(EVT VT) const { VT = VT.getScalarType(); if (!VT.isSimple()) return false; switch (VT.getSimpleVT().SimpleTy) { case MVT::f32: return false; /* There is V_MAD_F32 for f32 */ case MVT::f64: return true; default: break; } return false; } //===----------------------------------------------------------------------===// // Custom DAG Lowering Operations //===----------------------------------------------------------------------===// SDValue SITargetLowering::LowerOperation(SDValue Op, SelectionDAG &DAG) const { MachineFunction &MF = DAG.getMachineFunction(); SIMachineFunctionInfo *MFI = MF.getInfo(); switch (Op.getOpcode()) { default: return AMDGPUTargetLowering::LowerOperation(Op, DAG); case ISD::BRCOND: return LowerBRCOND(Op, DAG); case ISD::LOAD: { LoadSDNode *Load = dyn_cast(Op); if (Op.getValueType().isVector() && (Load->getAddressSpace() == AMDGPUAS::LOCAL_ADDRESS || Load->getAddressSpace() == AMDGPUAS::PRIVATE_ADDRESS || (Load->getAddressSpace() == AMDGPUAS::GLOBAL_ADDRESS && Op.getValueType().getVectorNumElements() > 4))) { SDValue MergedValues[2] = { SplitVectorLoad(Op, DAG), Load->getChain() }; return DAG.getMergeValues(MergedValues, SDLoc(Op)); } else { return LowerLOAD(Op, DAG); } } case ISD::SELECT: return LowerSELECT(Op, DAG); case ISD::STORE: return LowerSTORE(Op, DAG); case ISD::GlobalAddress: return LowerGlobalAddress(MFI, Op, DAG); case ISD::INTRINSIC_WO_CHAIN: { unsigned IntrinsicID = cast(Op.getOperand(0))->getZExtValue(); EVT VT = Op.getValueType(); SDLoc DL(Op); //XXX: Hardcoded we only use two to store the pointer to the parameters. unsigned NumUserSGPRs = 2; switch (IntrinsicID) { default: return AMDGPUTargetLowering::LowerOperation(Op, DAG); case Intrinsic::r600_read_ngroups_x: return LowerParameter(DAG, VT, VT, DL, DAG.getEntryNode(), 0, false); case Intrinsic::r600_read_ngroups_y: return LowerParameter(DAG, VT, VT, DL, DAG.getEntryNode(), 4, false); case Intrinsic::r600_read_ngroups_z: return LowerParameter(DAG, VT, VT, DL, DAG.getEntryNode(), 8, false); case Intrinsic::r600_read_global_size_x: return LowerParameter(DAG, VT, VT, DL, DAG.getEntryNode(), 12, false); case Intrinsic::r600_read_global_size_y: return LowerParameter(DAG, VT, VT, DL, DAG.getEntryNode(), 16, false); case Intrinsic::r600_read_global_size_z: return LowerParameter(DAG, VT, VT, DL, DAG.getEntryNode(), 20, false); case Intrinsic::r600_read_local_size_x: return LowerParameter(DAG, VT, VT, DL, DAG.getEntryNode(), 24, false); case Intrinsic::r600_read_local_size_y: return LowerParameter(DAG, VT, VT, DL, DAG.getEntryNode(), 28, false); case Intrinsic::r600_read_local_size_z: return LowerParameter(DAG, VT, VT, DL, DAG.getEntryNode(), 32, false); case Intrinsic::r600_read_tgid_x: return CreateLiveInRegister(DAG, &AMDGPU::SReg_32RegClass, AMDGPU::SReg_32RegClass.getRegister(NumUserSGPRs + 0), VT); case Intrinsic::r600_read_tgid_y: return CreateLiveInRegister(DAG, &AMDGPU::SReg_32RegClass, AMDGPU::SReg_32RegClass.getRegister(NumUserSGPRs + 1), VT); case Intrinsic::r600_read_tgid_z: return CreateLiveInRegister(DAG, &AMDGPU::SReg_32RegClass, AMDGPU::SReg_32RegClass.getRegister(NumUserSGPRs + 2), VT); case Intrinsic::r600_read_tidig_x: return CreateLiveInRegister(DAG, &AMDGPU::VReg_32RegClass, AMDGPU::VGPR0, VT); case Intrinsic::r600_read_tidig_y: return CreateLiveInRegister(DAG, &AMDGPU::VReg_32RegClass, AMDGPU::VGPR1, VT); case Intrinsic::r600_read_tidig_z: return CreateLiveInRegister(DAG, &AMDGPU::VReg_32RegClass, AMDGPU::VGPR2, VT); case AMDGPUIntrinsic::SI_load_const: { SDValue Ops [] = { Op.getOperand(1), Op.getOperand(2) }; MachineMemOperand *MMO = MF.getMachineMemOperand( MachinePointerInfo(), MachineMemOperand::MOLoad | MachineMemOperand::MOInvariant, VT.getSizeInBits() / 8, 4); return DAG.getMemIntrinsicNode(AMDGPUISD::LOAD_CONSTANT, DL, Op->getVTList(), Ops, VT, MMO); } case AMDGPUIntrinsic::SI_sample: return LowerSampleIntrinsic(AMDGPUISD::SAMPLE, Op, DAG); case AMDGPUIntrinsic::SI_sampleb: return LowerSampleIntrinsic(AMDGPUISD::SAMPLEB, Op, DAG); case AMDGPUIntrinsic::SI_sampled: return LowerSampleIntrinsic(AMDGPUISD::SAMPLED, Op, DAG); case AMDGPUIntrinsic::SI_samplel: return LowerSampleIntrinsic(AMDGPUISD::SAMPLEL, Op, DAG); case AMDGPUIntrinsic::SI_vs_load_input: return DAG.getNode(AMDGPUISD::LOAD_INPUT, DL, VT, Op.getOperand(1), Op.getOperand(2), Op.getOperand(3)); } } case ISD::INTRINSIC_VOID: SDValue Chain = Op.getOperand(0); unsigned IntrinsicID = cast(Op.getOperand(1))->getZExtValue(); switch (IntrinsicID) { case AMDGPUIntrinsic::SI_tbuffer_store: { SDLoc DL(Op); SDValue Ops [] = { Chain, Op.getOperand(2), Op.getOperand(3), Op.getOperand(4), Op.getOperand(5), Op.getOperand(6), Op.getOperand(7), Op.getOperand(8), Op.getOperand(9), Op.getOperand(10), Op.getOperand(11), Op.getOperand(12), Op.getOperand(13), Op.getOperand(14) }; EVT VT = Op.getOperand(3).getValueType(); MachineMemOperand *MMO = MF.getMachineMemOperand( MachinePointerInfo(), MachineMemOperand::MOStore, VT.getSizeInBits() / 8, 4); return DAG.getMemIntrinsicNode(AMDGPUISD::TBUFFER_STORE_FORMAT, DL, Op->getVTList(), Ops, VT, MMO); } default: break; } } return SDValue(); } /// \brief Helper function for LowerBRCOND static SDNode *findUser(SDValue Value, unsigned Opcode) { SDNode *Parent = Value.getNode(); for (SDNode::use_iterator I = Parent->use_begin(), E = Parent->use_end(); I != E; ++I) { if (I.getUse().get() != Value) continue; if (I->getOpcode() == Opcode) return *I; } return nullptr; } /// This transforms the control flow intrinsics to get the branch destination as /// last parameter, also switches branch target with BR if the need arise SDValue SITargetLowering::LowerBRCOND(SDValue BRCOND, SelectionDAG &DAG) const { SDLoc DL(BRCOND); SDNode *Intr = BRCOND.getOperand(1).getNode(); SDValue Target = BRCOND.getOperand(2); SDNode *BR = nullptr; if (Intr->getOpcode() == ISD::SETCC) { // As long as we negate the condition everything is fine SDNode *SetCC = Intr; assert(SetCC->getConstantOperandVal(1) == 1); assert(cast(SetCC->getOperand(2).getNode())->get() == ISD::SETNE); Intr = SetCC->getOperand(0).getNode(); } else { // Get the target from BR if we don't negate the condition BR = findUser(BRCOND, ISD::BR); Target = BR->getOperand(1); } assert(Intr->getOpcode() == ISD::INTRINSIC_W_CHAIN); // Build the result and SmallVector Res; for (unsigned i = 1, e = Intr->getNumValues(); i != e; ++i) Res.push_back(Intr->getValueType(i)); // operands of the new intrinsic call SmallVector Ops; Ops.push_back(BRCOND.getOperand(0)); for (unsigned i = 1, e = Intr->getNumOperands(); i != e; ++i) Ops.push_back(Intr->getOperand(i)); Ops.push_back(Target); // build the new intrinsic call SDNode *Result = DAG.getNode( Res.size() > 1 ? ISD::INTRINSIC_W_CHAIN : ISD::INTRINSIC_VOID, DL, DAG.getVTList(Res), Ops).getNode(); if (BR) { // Give the branch instruction our target SDValue Ops[] = { BR->getOperand(0), BRCOND.getOperand(2) }; DAG.MorphNodeTo(BR, ISD::BR, BR->getVTList(), Ops); } SDValue Chain = SDValue(Result, Result->getNumValues() - 1); // Copy the intrinsic results to registers for (unsigned i = 1, e = Intr->getNumValues() - 1; i != e; ++i) { SDNode *CopyToReg = findUser(SDValue(Intr, i), ISD::CopyToReg); if (!CopyToReg) continue; Chain = DAG.getCopyToReg( Chain, DL, CopyToReg->getOperand(1), SDValue(Result, i - 1), SDValue()); DAG.ReplaceAllUsesWith(SDValue(CopyToReg, 0), CopyToReg->getOperand(0)); } // Remove the old intrinsic from the chain DAG.ReplaceAllUsesOfValueWith( SDValue(Intr, Intr->getNumValues() - 1), Intr->getOperand(0)); return Chain; } SDValue SITargetLowering::LowerLOAD(SDValue Op, SelectionDAG &DAG) const { SDLoc DL(Op); LoadSDNode *Load = cast(Op); SDValue Ret = AMDGPUTargetLowering::LowerLOAD(Op, DAG); SDValue MergedValues[2]; MergedValues[1] = Load->getChain(); if (Ret.getNode()) { MergedValues[0] = Ret; return DAG.getMergeValues(MergedValues, DL); } if (Load->getAddressSpace() != AMDGPUAS::PRIVATE_ADDRESS) { return SDValue(); } EVT MemVT = Load->getMemoryVT(); assert(!MemVT.isVector() && "Private loads should be scalarized"); assert(!MemVT.isFloatingPoint() && "FP loads should be promoted to int"); SDValue Ptr = DAG.getNode(ISD::SRL, DL, MVT::i32, Load->getBasePtr(), DAG.getConstant(2, MVT::i32)); Ret = DAG.getNode(AMDGPUISD::REGISTER_LOAD, DL, MVT::i32, Load->getChain(), Ptr, DAG.getTargetConstant(0, MVT::i32), Op.getOperand(2)); if (MemVT.getSizeInBits() == 64) { SDValue IncPtr = DAG.getNode(ISD::ADD, DL, MVT::i32, Ptr, DAG.getConstant(1, MVT::i32)); SDValue LoadUpper = DAG.getNode(AMDGPUISD::REGISTER_LOAD, DL, MVT::i32, Load->getChain(), IncPtr, DAG.getTargetConstant(0, MVT::i32), Op.getOperand(2)); Ret = DAG.getNode(ISD::BUILD_PAIR, DL, MVT::i64, Ret, LoadUpper); } MergedValues[0] = Ret; return DAG.getMergeValues(MergedValues, DL); } SDValue SITargetLowering::LowerSampleIntrinsic(unsigned Opcode, const SDValue &Op, SelectionDAG &DAG) const { return DAG.getNode(Opcode, SDLoc(Op), Op.getValueType(), Op.getOperand(1), Op.getOperand(2), Op.getOperand(3), Op.getOperand(4)); } SDValue SITargetLowering::LowerSELECT(SDValue Op, SelectionDAG &DAG) const { if (Op.getValueType() != MVT::i64) return SDValue(); SDLoc DL(Op); SDValue Cond = Op.getOperand(0); SDValue Zero = DAG.getConstant(0, MVT::i32); SDValue One = DAG.getConstant(1, MVT::i32); SDValue LHS = DAG.getNode(ISD::BITCAST, DL, MVT::v2i32, Op.getOperand(1)); SDValue RHS = DAG.getNode(ISD::BITCAST, DL, MVT::v2i32, Op.getOperand(2)); SDValue Lo0 = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, DL, MVT::i32, LHS, Zero); SDValue Lo1 = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, DL, MVT::i32, RHS, Zero); SDValue Lo = DAG.getSelect(DL, MVT::i32, Cond, Lo0, Lo1); SDValue Hi0 = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, DL, MVT::i32, LHS, One); SDValue Hi1 = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, DL, MVT::i32, RHS, One); SDValue Hi = DAG.getSelect(DL, MVT::i32, Cond, Hi0, Hi1); SDValue Res = DAG.getNode(ISD::BUILD_VECTOR, DL, MVT::v2i32, Lo, Hi); return DAG.getNode(ISD::BITCAST, DL, MVT::i64, Res); } SDValue SITargetLowering::LowerSTORE(SDValue Op, SelectionDAG &DAG) const { SDLoc DL(Op); StoreSDNode *Store = cast(Op); EVT VT = Store->getMemoryVT(); // These stores are legal. if (Store->getAddressSpace() == AMDGPUAS::LOCAL_ADDRESS && VT.isVector() && VT.getVectorNumElements() == 2 && VT.getVectorElementType() == MVT::i32) return SDValue(); SDValue Ret = AMDGPUTargetLowering::LowerSTORE(Op, DAG); if (Ret.getNode()) return Ret; if (VT.isVector() && VT.getVectorNumElements() >= 8) return SplitVectorStore(Op, DAG); if (VT == MVT::i1) return DAG.getTruncStore(Store->getChain(), DL, DAG.getSExtOrTrunc(Store->getValue(), DL, MVT::i32), Store->getBasePtr(), MVT::i1, Store->getMemOperand()); if (Store->getAddressSpace() != AMDGPUAS::PRIVATE_ADDRESS) return SDValue(); SDValue Ptr = DAG.getNode(ISD::SRL, DL, MVT::i32, Store->getBasePtr(), DAG.getConstant(2, MVT::i32)); SDValue Chain = Store->getChain(); SmallVector Values; if (Store->isTruncatingStore()) { unsigned Mask = 0; if (Store->getMemoryVT() == MVT::i8) { Mask = 0xff; } else if (Store->getMemoryVT() == MVT::i16) { Mask = 0xffff; } SDValue Dst = DAG.getNode(AMDGPUISD::REGISTER_LOAD, DL, MVT::i32, Chain, Store->getBasePtr(), DAG.getConstant(0, MVT::i32)); SDValue ByteIdx = DAG.getNode(ISD::AND, DL, MVT::i32, Store->getBasePtr(), DAG.getConstant(0x3, MVT::i32)); SDValue ShiftAmt = DAG.getNode(ISD::SHL, DL, MVT::i32, ByteIdx, DAG.getConstant(3, MVT::i32)); SDValue MaskedValue = DAG.getNode(ISD::AND, DL, MVT::i32, Store->getValue(), DAG.getConstant(Mask, MVT::i32)); SDValue ShiftedValue = DAG.getNode(ISD::SHL, DL, MVT::i32, MaskedValue, ShiftAmt); SDValue RotrAmt = DAG.getNode(ISD::SUB, DL, MVT::i32, DAG.getConstant(32, MVT::i32), ShiftAmt); SDValue DstMask = DAG.getNode(ISD::ROTR, DL, MVT::i32, DAG.getConstant(Mask, MVT::i32), RotrAmt); Dst = DAG.getNode(ISD::AND, DL, MVT::i32, Dst, DstMask); Dst = DAG.getNode(ISD::OR, DL, MVT::i32, Dst, ShiftedValue); Values.push_back(Dst); } else if (VT == MVT::i64) { for (unsigned i = 0; i < 2; ++i) { Values.push_back(DAG.getNode(ISD::EXTRACT_ELEMENT, DL, MVT::i32, Store->getValue(), DAG.getConstant(i, MVT::i32))); } } else if (VT == MVT::i128) { for (unsigned i = 0; i < 2; ++i) { for (unsigned j = 0; j < 2; ++j) { Values.push_back(DAG.getNode(ISD::EXTRACT_ELEMENT, DL, MVT::i32, DAG.getNode(ISD::EXTRACT_ELEMENT, DL, MVT::i64, Store->getValue(), DAG.getConstant(i, MVT::i32)), DAG.getConstant(j, MVT::i32))); } } } else { Values.push_back(Store->getValue()); } for (unsigned i = 0; i < Values.size(); ++i) { SDValue PartPtr = DAG.getNode(ISD::ADD, DL, MVT::i32, Ptr, DAG.getConstant(i, MVT::i32)); Chain = DAG.getNode(AMDGPUISD::REGISTER_STORE, DL, MVT::Other, Chain, Values[i], PartPtr, DAG.getTargetConstant(0, MVT::i32)); } return Chain; } //===----------------------------------------------------------------------===// // Custom DAG optimizations //===----------------------------------------------------------------------===// SDValue SITargetLowering::performUCharToFloatCombine(SDNode *N, DAGCombinerInfo &DCI) { EVT VT = N->getValueType(0); EVT ScalarVT = VT.getScalarType(); if (ScalarVT != MVT::f32) return SDValue(); SelectionDAG &DAG = DCI.DAG; SDLoc DL(N); SDValue Src = N->getOperand(0); EVT SrcVT = Src.getValueType(); // TODO: We could try to match extracting the higher bytes, which would be // easier if i8 vectors weren't promoted to i32 vectors, particularly after // types are legalized. v4i8 -> v4f32 is probably the only case to worry // about in practice. if (DCI.isAfterLegalizeVectorOps() && SrcVT == MVT::i32) { if (DAG.MaskedValueIsZero(Src, APInt::getHighBitsSet(32, 24))) { SDValue Cvt = DAG.getNode(AMDGPUISD::CVT_F32_UBYTE0, DL, VT, Src); DCI.AddToWorklist(Cvt.getNode()); return Cvt; } } // We are primarily trying to catch operations on illegal vector types // before they are expanded. // For scalars, we can use the more flexible method of checking masked bits // after legalization. if (!DCI.isBeforeLegalize() || !SrcVT.isVector() || SrcVT.getVectorElementType() != MVT::i8) { return SDValue(); } assert(DCI.isBeforeLegalize() && "Unexpected legal type"); // Weird sized vectors are a pain to handle, but we know 3 is really the same // size as 4. unsigned NElts = SrcVT.getVectorNumElements(); if (!SrcVT.isSimple() && NElts != 3) return SDValue(); // Handle v4i8 -> v4f32 extload. Replace the v4i8 with a legal i32 load to // prevent a mess from expanding to v4i32 and repacking. if (ISD::isNormalLoad(Src.getNode()) && Src.hasOneUse()) { EVT LoadVT = getEquivalentMemType(*DAG.getContext(), SrcVT); EVT RegVT = getEquivalentLoadRegType(*DAG.getContext(), SrcVT); EVT FloatVT = EVT::getVectorVT(*DAG.getContext(), MVT::f32, NElts); LoadSDNode *Load = cast(Src); SDValue NewLoad = DAG.getExtLoad(ISD::ZEXTLOAD, DL, RegVT, Load->getChain(), Load->getBasePtr(), LoadVT, Load->getMemOperand()); // Make sure successors of the original load stay after it by updating // them to use the new Chain. DAG.ReplaceAllUsesOfValueWith(SDValue(Load, 1), NewLoad.getValue(1)); SmallVector Elts; if (RegVT.isVector()) DAG.ExtractVectorElements(NewLoad, Elts); else Elts.push_back(NewLoad); SmallVector Ops; unsigned EltIdx = 0; for (SDValue Elt : Elts) { unsigned ComponentsInElt = std::min(4u, NElts - 4 * EltIdx); for (unsigned I = 0; I < ComponentsInElt; ++I) { unsigned Opc = AMDGPUISD::CVT_F32_UBYTE0 + I; SDValue Cvt = DAG.getNode(Opc, DL, MVT::f32, Elt); DCI.AddToWorklist(Cvt.getNode()); Ops.push_back(Cvt); } ++EltIdx; } assert(Ops.size() == NElts); return DAG.getNode(ISD::BUILD_VECTOR, DL, FloatVT, Ops); } return SDValue(); } SDValue SITargetLowering::PerformDAGCombine(SDNode *N, DAGCombinerInfo &DCI) const { SelectionDAG &DAG = DCI.DAG; SDLoc DL(N); EVT VT = N->getValueType(0); switch (N->getOpcode()) { default: return AMDGPUTargetLowering::PerformDAGCombine(N, DCI); case ISD::SELECT_CC: { ConstantSDNode *True, *False; // i1 selectcc(l, r, -1, 0, cc) -> i1 setcc(l, r, cc) if ((True = dyn_cast(N->getOperand(2))) && (False = dyn_cast(N->getOperand(3))) && True->isAllOnesValue() && False->isNullValue() && VT == MVT::i1) { return DAG.getNode(ISD::SETCC, DL, VT, N->getOperand(0), N->getOperand(1), N->getOperand(4)); } break; } case ISD::SETCC: { SDValue Arg0 = N->getOperand(0); SDValue Arg1 = N->getOperand(1); SDValue CC = N->getOperand(2); ConstantSDNode * C = nullptr; ISD::CondCode CCOp = dyn_cast(CC)->get(); // i1 setcc (sext(i1), 0, setne) -> i1 setcc(i1, 0, setne) if (VT == MVT::i1 && Arg0.getOpcode() == ISD::SIGN_EXTEND && Arg0.getOperand(0).getValueType() == MVT::i1 && (C = dyn_cast(Arg1)) && C->isNullValue() && CCOp == ISD::SETNE) { return SimplifySetCC(VT, Arg0.getOperand(0), DAG.getConstant(0, MVT::i1), CCOp, true, DCI, DL); } break; } case AMDGPUISD::CVT_F32_UBYTE0: case AMDGPUISD::CVT_F32_UBYTE1: case AMDGPUISD::CVT_F32_UBYTE2: case AMDGPUISD::CVT_F32_UBYTE3: { unsigned Offset = N->getOpcode() - AMDGPUISD::CVT_F32_UBYTE0; SDValue Src = N->getOperand(0); APInt Demanded = APInt::getBitsSet(32, 8 * Offset, 8 * Offset + 8); APInt KnownZero, KnownOne; TargetLowering::TargetLoweringOpt TLO(DAG, !DCI.isBeforeLegalize(), !DCI.isBeforeLegalizeOps()); const TargetLowering &TLI = DAG.getTargetLoweringInfo(); if (TLO.ShrinkDemandedConstant(Src, Demanded) || TLI.SimplifyDemandedBits(Src, Demanded, KnownZero, KnownOne, TLO)) { DCI.CommitTargetLoweringOpt(TLO); } break; } case ISD::UINT_TO_FP: { return performUCharToFloatCombine(N, DCI); } } return AMDGPUTargetLowering::PerformDAGCombine(N, DCI); } /// \brief Test if RegClass is one of the VSrc classes static bool isVSrc(unsigned RegClass) { return AMDGPU::VSrc_32RegClassID == RegClass || AMDGPU::VSrc_64RegClassID == RegClass; } /// \brief Test if RegClass is one of the SSrc classes static bool isSSrc(unsigned RegClass) { return AMDGPU::SSrc_32RegClassID == RegClass || AMDGPU::SSrc_64RegClassID == RegClass; } /// \brief Analyze the possible immediate value Op /// /// Returns -1 if it isn't an immediate, 0 if it's and inline immediate /// and the immediate value if it's a literal immediate int32_t SITargetLowering::analyzeImmediate(const SDNode *N) const { union { int32_t I; float F; } Imm; if (const ConstantSDNode *Node = dyn_cast(N)) { if (Node->getZExtValue() >> 32) { return -1; } Imm.I = Node->getSExtValue(); } else if (const ConstantFPSDNode *Node = dyn_cast(N)) { if (N->getValueType(0) != MVT::f32) return -1; Imm.F = Node->getValueAPF().convertToFloat(); } else return -1; // It isn't an immediate if ((Imm.I >= -16 && Imm.I <= 64) || Imm.F == 0.5f || Imm.F == -0.5f || Imm.F == 1.0f || Imm.F == -1.0f || Imm.F == 2.0f || Imm.F == -2.0f || Imm.F == 4.0f || Imm.F == -4.0f) return 0; // It's an inline immediate return Imm.I; // It's a literal immediate } /// \brief Try to fold an immediate directly into an instruction bool SITargetLowering::foldImm(SDValue &Operand, int32_t &Immediate, bool &ScalarSlotUsed) const { MachineSDNode *Mov = dyn_cast(Operand); const SIInstrInfo *TII = static_cast(getTargetMachine().getInstrInfo()); if (!Mov || !TII->isMov(Mov->getMachineOpcode())) return false; const SDValue &Op = Mov->getOperand(0); int32_t Value = analyzeImmediate(Op.getNode()); if (Value == -1) { // Not an immediate at all return false; } else if (Value == 0) { // Inline immediates can always be fold Operand = Op; return true; } else if (Value == Immediate) { // Already fold literal immediate Operand = Op; return true; } else if (!ScalarSlotUsed && !Immediate) { // Fold this literal immediate ScalarSlotUsed = true; Immediate = Value; Operand = Op; return true; } return false; } const TargetRegisterClass *SITargetLowering::getRegClassForNode( SelectionDAG &DAG, const SDValue &Op) const { const SIInstrInfo *TII = static_cast(getTargetMachine().getInstrInfo()); const SIRegisterInfo &TRI = TII->getRegisterInfo(); if (!Op->isMachineOpcode()) { switch(Op->getOpcode()) { case ISD::CopyFromReg: { MachineRegisterInfo &MRI = DAG.getMachineFunction().getRegInfo(); unsigned Reg = cast(Op->getOperand(1))->getReg(); if (TargetRegisterInfo::isVirtualRegister(Reg)) { return MRI.getRegClass(Reg); } return TRI.getPhysRegClass(Reg); } default: return nullptr; } } const MCInstrDesc &Desc = TII->get(Op->getMachineOpcode()); int OpClassID = Desc.OpInfo[Op.getResNo()].RegClass; if (OpClassID != -1) { return TRI.getRegClass(OpClassID); } switch(Op.getMachineOpcode()) { case AMDGPU::COPY_TO_REGCLASS: // Operand 1 is the register class id for COPY_TO_REGCLASS instructions. OpClassID = cast(Op->getOperand(1))->getZExtValue(); // If the COPY_TO_REGCLASS instruction is copying to a VSrc register // class, then the register class for the value could be either a // VReg or and SReg. In order to get a more accurate if (OpClassID == AMDGPU::VSrc_32RegClassID || OpClassID == AMDGPU::VSrc_64RegClassID) { return getRegClassForNode(DAG, Op.getOperand(0)); } return TRI.getRegClass(OpClassID); case AMDGPU::EXTRACT_SUBREG: { int SubIdx = cast(Op.getOperand(1))->getZExtValue(); const TargetRegisterClass *SuperClass = getRegClassForNode(DAG, Op.getOperand(0)); return TRI.getSubClassWithSubReg(SuperClass, SubIdx); } case AMDGPU::REG_SEQUENCE: // Operand 0 is the register class id for REG_SEQUENCE instructions. return TRI.getRegClass( cast(Op.getOperand(0))->getZExtValue()); default: return getRegClassFor(Op.getSimpleValueType()); } } /// \brief Does "Op" fit into register class "RegClass" ? bool SITargetLowering::fitsRegClass(SelectionDAG &DAG, const SDValue &Op, unsigned RegClass) const { const TargetRegisterInfo *TRI = getTargetMachine().getRegisterInfo(); const TargetRegisterClass *RC = getRegClassForNode(DAG, Op); if (!RC) { return false; } return TRI->getRegClass(RegClass)->hasSubClassEq(RC); } /// \brief Make sure that we don't exeed the number of allowed scalars void SITargetLowering::ensureSRegLimit(SelectionDAG &DAG, SDValue &Operand, unsigned RegClass, bool &ScalarSlotUsed) const { // First map the operands register class to a destination class if (RegClass == AMDGPU::VSrc_32RegClassID) RegClass = AMDGPU::VReg_32RegClassID; else if (RegClass == AMDGPU::VSrc_64RegClassID) RegClass = AMDGPU::VReg_64RegClassID; else return; // Nothing to do if they fit naturally if (fitsRegClass(DAG, Operand, RegClass)) return; // If the scalar slot isn't used yet use it now if (!ScalarSlotUsed) { ScalarSlotUsed = true; return; } // This is a conservative aproach. It is possible that we can't determine the // correct register class and copy too often, but better safe than sorry. SDValue RC = DAG.getTargetConstant(RegClass, MVT::i32); SDNode *Node = DAG.getMachineNode(TargetOpcode::COPY_TO_REGCLASS, SDLoc(), Operand.getValueType(), Operand, RC); Operand = SDValue(Node, 0); } /// \returns true if \p Node's operands are different from the SDValue list /// \p Ops static bool isNodeChanged(const SDNode *Node, const std::vector &Ops) { for (unsigned i = 0, e = Node->getNumOperands(); i < e; ++i) { if (Ops[i].getNode() != Node->getOperand(i).getNode()) { return true; } } return false; } /// \brief Try to fold the Nodes operands into the Node SDNode *SITargetLowering::foldOperands(MachineSDNode *Node, SelectionDAG &DAG) const { // Original encoding (either e32 or e64) int Opcode = Node->getMachineOpcode(); const SIInstrInfo *TII = static_cast(getTargetMachine().getInstrInfo()); const MCInstrDesc *Desc = &TII->get(Opcode); unsigned NumDefs = Desc->getNumDefs(); unsigned NumOps = Desc->getNumOperands(); // Commuted opcode if available int OpcodeRev = Desc->isCommutable() ? TII->commuteOpcode(Opcode) : -1; const MCInstrDesc *DescRev = OpcodeRev == -1 ? nullptr : &TII->get(OpcodeRev); assert(!DescRev || DescRev->getNumDefs() == NumDefs); assert(!DescRev || DescRev->getNumOperands() == NumOps); // e64 version if available, -1 otherwise int OpcodeE64 = AMDGPU::getVOPe64(Opcode); const MCInstrDesc *DescE64 = OpcodeE64 == -1 ? nullptr : &TII->get(OpcodeE64); int InputModifiers[3] = {0}; assert(!DescE64 || DescE64->getNumDefs() == NumDefs); int32_t Immediate = Desc->getSize() == 4 ? 0 : -1; bool HaveVSrc = false, HaveSSrc = false; // First figure out what we already have in this instruction. for (unsigned i = 0, e = Node->getNumOperands(), Op = NumDefs; i != e && Op < NumOps; ++i, ++Op) { unsigned RegClass = Desc->OpInfo[Op].RegClass; if (isVSrc(RegClass)) HaveVSrc = true; else if (isSSrc(RegClass)) HaveSSrc = true; else continue; int32_t Imm = analyzeImmediate(Node->getOperand(i).getNode()); if (Imm != -1 && Imm != 0) { // Literal immediate Immediate = Imm; } } // If we neither have VSrc nor SSrc, it makes no sense to continue. if (!HaveVSrc && !HaveSSrc) return Node; // No scalar allowed when we have both VSrc and SSrc bool ScalarSlotUsed = HaveVSrc && HaveSSrc; // Second go over the operands and try to fold them std::vector Ops; bool Promote2e64 = false; for (unsigned i = 0, e = Node->getNumOperands(), Op = NumDefs; i != e && Op < NumOps; ++i, ++Op) { const SDValue &Operand = Node->getOperand(i); Ops.push_back(Operand); // Already folded immediate? if (isa(Operand.getNode()) || isa(Operand.getNode())) continue; // Is this a VSrc or SSrc operand? unsigned RegClass = Desc->OpInfo[Op].RegClass; if (isVSrc(RegClass) || isSSrc(RegClass)) { // Try to fold the immediates if (!foldImm(Ops[i], Immediate, ScalarSlotUsed)) { // Folding didn't work, make sure we don't hit the SReg limit. ensureSRegLimit(DAG, Ops[i], RegClass, ScalarSlotUsed); } continue; } if (i == 1 && DescRev && fitsRegClass(DAG, Ops[0], RegClass)) { unsigned OtherRegClass = Desc->OpInfo[NumDefs].RegClass; assert(isVSrc(OtherRegClass) || isSSrc(OtherRegClass)); // Test if it makes sense to swap operands if (foldImm(Ops[1], Immediate, ScalarSlotUsed) || (!fitsRegClass(DAG, Ops[1], RegClass) && fitsRegClass(DAG, Ops[1], OtherRegClass))) { // Swap commutable operands std::swap(Ops[0], Ops[1]); Desc = DescRev; DescRev = nullptr; continue; } } if (Immediate) continue; if (DescE64) { // Test if it makes sense to switch to e64 encoding unsigned OtherRegClass = DescE64->OpInfo[Op].RegClass; if (!isVSrc(OtherRegClass) && !isSSrc(OtherRegClass)) continue; int32_t TmpImm = -1; if (foldImm(Ops[i], TmpImm, ScalarSlotUsed) || (!fitsRegClass(DAG, Ops[i], RegClass) && fitsRegClass(DAG, Ops[1], OtherRegClass))) { // Switch to e64 encoding Immediate = -1; Promote2e64 = true; Desc = DescE64; DescE64 = nullptr; } } if (!DescE64 && !Promote2e64) continue; if (!Operand.isMachineOpcode()) continue; if (Operand.getMachineOpcode() == AMDGPU::FNEG_SI) { Ops.pop_back(); Ops.push_back(Operand.getOperand(0)); InputModifiers[i] = 1; Promote2e64 = true; if (!DescE64) continue; Desc = DescE64; DescE64 = nullptr; } else if (Operand.getMachineOpcode() == AMDGPU::FABS_SI) { Ops.pop_back(); Ops.push_back(Operand.getOperand(0)); InputModifiers[i] = 2; Promote2e64 = true; if (!DescE64) continue; Desc = DescE64; DescE64 = nullptr; } } if (Promote2e64) { std::vector OldOps(Ops); Ops.clear(); for (unsigned i = 0; i < OldOps.size(); ++i) { // src_modifier Ops.push_back(DAG.getTargetConstant(InputModifiers[i], MVT::i32)); Ops.push_back(OldOps[i]); } // Add the modifier flags while promoting for (unsigned i = 0; i < 2; ++i) Ops.push_back(DAG.getTargetConstant(0, MVT::i32)); } // Add optional chain and glue for (unsigned i = NumOps - NumDefs, e = Node->getNumOperands(); i < e; ++i) Ops.push_back(Node->getOperand(i)); // Nodes that have a glue result are not CSE'd by getMachineNode(), so in // this case a brand new node is always be created, even if the operands // are the same as before. So, manually check if anything has been changed. if (Desc->Opcode == Opcode && !isNodeChanged(Node, Ops)) { return Node; } // Create a complete new instruction return DAG.getMachineNode(Desc->Opcode, SDLoc(Node), Node->getVTList(), Ops); } /// \brief Helper function for adjustWritemask static unsigned SubIdx2Lane(unsigned Idx) { switch (Idx) { default: return 0; case AMDGPU::sub0: return 0; case AMDGPU::sub1: return 1; case AMDGPU::sub2: return 2; case AMDGPU::sub3: return 3; } } /// \brief Adjust the writemask of MIMG instructions void SITargetLowering::adjustWritemask(MachineSDNode *&Node, SelectionDAG &DAG) const { SDNode *Users[4] = { }; unsigned Lane = 0; unsigned OldDmask = Node->getConstantOperandVal(0); unsigned NewDmask = 0; // Try to figure out the used register components for (SDNode::use_iterator I = Node->use_begin(), E = Node->use_end(); I != E; ++I) { // Abort if we can't understand the usage if (!I->isMachineOpcode() || I->getMachineOpcode() != TargetOpcode::EXTRACT_SUBREG) return; // Lane means which subreg of %VGPRa_VGPRb_VGPRc_VGPRd is used. // Note that subregs are packed, i.e. Lane==0 is the first bit set // in OldDmask, so it can be any of X,Y,Z,W; Lane==1 is the second bit // set, etc. Lane = SubIdx2Lane(I->getConstantOperandVal(1)); // Set which texture component corresponds to the lane. unsigned Comp; for (unsigned i = 0, Dmask = OldDmask; i <= Lane; i++) { assert(Dmask); Comp = countTrailingZeros(Dmask); Dmask &= ~(1 << Comp); } // Abort if we have more than one user per component if (Users[Lane]) return; Users[Lane] = *I; NewDmask |= 1 << Comp; } // Abort if there's no change if (NewDmask == OldDmask) return; // Adjust the writemask in the node std::vector Ops; Ops.push_back(DAG.getTargetConstant(NewDmask, MVT::i32)); for (unsigned i = 1, e = Node->getNumOperands(); i != e; ++i) Ops.push_back(Node->getOperand(i)); Node = (MachineSDNode*)DAG.UpdateNodeOperands(Node, Ops); // If we only got one lane, replace it with a copy // (if NewDmask has only one bit set...) if (NewDmask && (NewDmask & (NewDmask-1)) == 0) { SDValue RC = DAG.getTargetConstant(AMDGPU::VReg_32RegClassID, MVT::i32); SDNode *Copy = DAG.getMachineNode(TargetOpcode::COPY_TO_REGCLASS, SDLoc(), Users[Lane]->getValueType(0), SDValue(Node, 0), RC); DAG.ReplaceAllUsesWith(Users[Lane], Copy); return; } // Update the users of the node with the new indices for (unsigned i = 0, Idx = AMDGPU::sub0; i < 4; ++i) { SDNode *User = Users[i]; if (!User) continue; SDValue Op = DAG.getTargetConstant(Idx, MVT::i32); DAG.UpdateNodeOperands(User, User->getOperand(0), Op); switch (Idx) { default: break; case AMDGPU::sub0: Idx = AMDGPU::sub1; break; case AMDGPU::sub1: Idx = AMDGPU::sub2; break; case AMDGPU::sub2: Idx = AMDGPU::sub3; break; } } } /// \brief Fold the instructions after selecting them. SDNode *SITargetLowering::PostISelFolding(MachineSDNode *Node, SelectionDAG &DAG) const { const SIInstrInfo *TII = static_cast(getTargetMachine().getInstrInfo()); Node = AdjustRegClass(Node, DAG); if (TII->isMIMG(Node->getMachineOpcode())) adjustWritemask(Node, DAG); return foldOperands(Node, DAG); } /// \brief Assign the register class depending on the number of /// bits set in the writemask void SITargetLowering::AdjustInstrPostInstrSelection(MachineInstr *MI, SDNode *Node) const { const SIInstrInfo *TII = static_cast(getTargetMachine().getInstrInfo()); if (!TII->isMIMG(MI->getOpcode())) return; unsigned VReg = MI->getOperand(0).getReg(); unsigned Writemask = MI->getOperand(1).getImm(); unsigned BitsSet = 0; for (unsigned i = 0; i < 4; ++i) BitsSet += Writemask & (1 << i) ? 1 : 0; const TargetRegisterClass *RC; switch (BitsSet) { default: return; case 1: RC = &AMDGPU::VReg_32RegClass; break; case 2: RC = &AMDGPU::VReg_64RegClass; break; case 3: RC = &AMDGPU::VReg_96RegClass; break; } unsigned NewOpcode = TII->getMaskedMIMGOp(MI->getOpcode(), BitsSet); MI->setDesc(TII->get(NewOpcode)); MachineRegisterInfo &MRI = MI->getParent()->getParent()->getRegInfo(); MRI.setRegClass(VReg, RC); } MachineSDNode *SITargetLowering::AdjustRegClass(MachineSDNode *N, SelectionDAG &DAG) const { SDLoc DL(N); unsigned NewOpcode = N->getMachineOpcode(); switch (N->getMachineOpcode()) { default: return N; case AMDGPU::S_LOAD_DWORD_IMM: NewOpcode = AMDGPU::BUFFER_LOAD_DWORD_ADDR64; // Fall-through case AMDGPU::S_LOAD_DWORDX2_SGPR: if (NewOpcode == N->getMachineOpcode()) { NewOpcode = AMDGPU::BUFFER_LOAD_DWORDX2_ADDR64; } // Fall-through case AMDGPU::S_LOAD_DWORDX4_IMM: case AMDGPU::S_LOAD_DWORDX4_SGPR: { if (NewOpcode == N->getMachineOpcode()) { NewOpcode = AMDGPU::BUFFER_LOAD_DWORDX4_ADDR64; } if (fitsRegClass(DAG, N->getOperand(0), AMDGPU::SReg_64RegClassID)) { return N; } ConstantSDNode *Offset = cast(N->getOperand(1)); SDValue Ops[] = { SDValue(DAG.getMachineNode(AMDGPU::SI_ADDR64_RSRC, DL, MVT::i128, DAG.getConstant(0, MVT::i64)), 0), N->getOperand(0), DAG.getConstant(Offset->getSExtValue() << 2, MVT::i32) }; return DAG.getMachineNode(NewOpcode, DL, N->getVTList(), Ops); } } } SDValue SITargetLowering::CreateLiveInRegister(SelectionDAG &DAG, const TargetRegisterClass *RC, unsigned Reg, EVT VT) const { SDValue VReg = AMDGPUTargetLowering::CreateLiveInRegister(DAG, RC, Reg, VT); return DAG.getCopyFromReg(DAG.getEntryNode(), SDLoc(DAG.getEntryNode()), cast(VReg)->getReg(), VT); }