| //===- AArch64RegisterBankInfo.cpp ----------------------------------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| /// \file |
| /// This file implements the targeting of the RegisterBankInfo class for |
| /// AArch64. |
| /// \todo This should be generated by TableGen. |
| //===----------------------------------------------------------------------===// |
| |
| #include "AArch64RegisterBankInfo.h" |
| #include "AArch64InstrInfo.h" |
| #include "llvm/ADT/SmallVector.h" |
| #include "llvm/CodeGen/GlobalISel/RegisterBank.h" |
| #include "llvm/CodeGen/GlobalISel/RegisterBankInfo.h" |
| #include "llvm/CodeGen/LowLevelType.h" |
| #include "llvm/CodeGen/MachineFunction.h" |
| #include "llvm/CodeGen/MachineInstr.h" |
| #include "llvm/CodeGen/MachineOperand.h" |
| #include "llvm/CodeGen/MachineRegisterInfo.h" |
| #include "llvm/CodeGen/TargetOpcodes.h" |
| #include "llvm/CodeGen/TargetRegisterInfo.h" |
| #include "llvm/CodeGen/TargetSubtargetInfo.h" |
| #include "llvm/Support/ErrorHandling.h" |
| #include <algorithm> |
| #include <cassert> |
| |
| #define GET_TARGET_REGBANK_IMPL |
| #include "AArch64GenRegisterBank.inc" |
| |
| // This file will be TableGen'ed at some point. |
| #include "AArch64GenRegisterBankInfo.def" |
| |
| using namespace llvm; |
| |
| AArch64RegisterBankInfo::AArch64RegisterBankInfo(const TargetRegisterInfo &TRI) |
| : AArch64GenRegisterBankInfo() { |
| static bool AlreadyInit = false; |
| // We have only one set of register banks, whatever the subtarget |
| // is. Therefore, the initialization of the RegBanks table should be |
| // done only once. Indeed the table of all register banks |
| // (AArch64::RegBanks) is unique in the compiler. At some point, it |
| // will get tablegen'ed and the whole constructor becomes empty. |
| if (AlreadyInit) |
| return; |
| AlreadyInit = true; |
| |
| const RegisterBank &RBGPR = getRegBank(AArch64::GPRRegBankID); |
| (void)RBGPR; |
| assert(&AArch64::GPRRegBank == &RBGPR && |
| "The order in RegBanks is messed up"); |
| |
| const RegisterBank &RBFPR = getRegBank(AArch64::FPRRegBankID); |
| (void)RBFPR; |
| assert(&AArch64::FPRRegBank == &RBFPR && |
| "The order in RegBanks is messed up"); |
| |
| const RegisterBank &RBCCR = getRegBank(AArch64::CCRegBankID); |
| (void)RBCCR; |
| assert(&AArch64::CCRegBank == &RBCCR && "The order in RegBanks is messed up"); |
| |
| // The GPR register bank is fully defined by all the registers in |
| // GR64all + its subclasses. |
| assert(RBGPR.covers(*TRI.getRegClass(AArch64::GPR32RegClassID)) && |
| "Subclass not added?"); |
| assert(RBGPR.getSize() == 64 && "GPRs should hold up to 64-bit"); |
| |
| // The FPR register bank is fully defined by all the registers in |
| // GR64all + its subclasses. |
| assert(RBFPR.covers(*TRI.getRegClass(AArch64::QQRegClassID)) && |
| "Subclass not added?"); |
| assert(RBFPR.covers(*TRI.getRegClass(AArch64::FPR64RegClassID)) && |
| "Subclass not added?"); |
| assert(RBFPR.getSize() == 512 && |
| "FPRs should hold up to 512-bit via QQQQ sequence"); |
| |
| assert(RBCCR.covers(*TRI.getRegClass(AArch64::CCRRegClassID)) && |
| "Class not added?"); |
| assert(RBCCR.getSize() == 32 && "CCR should hold up to 32-bit"); |
| |
| // Check that the TableGen'ed like file is in sync we our expectations. |
| // First, the Idx. |
| assert(checkPartialMappingIdx(PMI_FirstGPR, PMI_LastGPR, |
| {PMI_GPR32, PMI_GPR64}) && |
| "PartialMappingIdx's are incorrectly ordered"); |
| assert(checkPartialMappingIdx(PMI_FirstFPR, PMI_LastFPR, |
| {PMI_FPR16, PMI_FPR32, PMI_FPR64, PMI_FPR128, |
| PMI_FPR256, PMI_FPR512}) && |
| "PartialMappingIdx's are incorrectly ordered"); |
| // Now, the content. |
| // Check partial mapping. |
| #define CHECK_PARTIALMAP(Idx, ValStartIdx, ValLength, RB) \ |
| do { \ |
| assert( \ |
| checkPartialMap(PartialMappingIdx::Idx, ValStartIdx, ValLength, RB) && \ |
| #Idx " is incorrectly initialized"); \ |
| } while (false) |
| |
| CHECK_PARTIALMAP(PMI_GPR32, 0, 32, RBGPR); |
| CHECK_PARTIALMAP(PMI_GPR64, 0, 64, RBGPR); |
| CHECK_PARTIALMAP(PMI_FPR16, 0, 16, RBFPR); |
| CHECK_PARTIALMAP(PMI_FPR32, 0, 32, RBFPR); |
| CHECK_PARTIALMAP(PMI_FPR64, 0, 64, RBFPR); |
| CHECK_PARTIALMAP(PMI_FPR128, 0, 128, RBFPR); |
| CHECK_PARTIALMAP(PMI_FPR256, 0, 256, RBFPR); |
| CHECK_PARTIALMAP(PMI_FPR512, 0, 512, RBFPR); |
| |
| // Check value mapping. |
| #define CHECK_VALUEMAP_IMPL(RBName, Size, Offset) \ |
| do { \ |
| assert(checkValueMapImpl(PartialMappingIdx::PMI_##RBName##Size, \ |
| PartialMappingIdx::PMI_First##RBName, Size, \ |
| Offset) && \ |
| #RBName #Size " " #Offset " is incorrectly initialized"); \ |
| } while (false) |
| |
| #define CHECK_VALUEMAP(RBName, Size) CHECK_VALUEMAP_IMPL(RBName, Size, 0) |
| |
| CHECK_VALUEMAP(GPR, 32); |
| CHECK_VALUEMAP(GPR, 64); |
| CHECK_VALUEMAP(FPR, 16); |
| CHECK_VALUEMAP(FPR, 32); |
| CHECK_VALUEMAP(FPR, 64); |
| CHECK_VALUEMAP(FPR, 128); |
| CHECK_VALUEMAP(FPR, 256); |
| CHECK_VALUEMAP(FPR, 512); |
| |
| // Check the value mapping for 3-operands instructions where all the operands |
| // map to the same value mapping. |
| #define CHECK_VALUEMAP_3OPS(RBName, Size) \ |
| do { \ |
| CHECK_VALUEMAP_IMPL(RBName, Size, 0); \ |
| CHECK_VALUEMAP_IMPL(RBName, Size, 1); \ |
| CHECK_VALUEMAP_IMPL(RBName, Size, 2); \ |
| } while (false) |
| |
| CHECK_VALUEMAP_3OPS(GPR, 32); |
| CHECK_VALUEMAP_3OPS(GPR, 64); |
| CHECK_VALUEMAP_3OPS(FPR, 32); |
| CHECK_VALUEMAP_3OPS(FPR, 64); |
| CHECK_VALUEMAP_3OPS(FPR, 128); |
| CHECK_VALUEMAP_3OPS(FPR, 256); |
| CHECK_VALUEMAP_3OPS(FPR, 512); |
| |
| #define CHECK_VALUEMAP_CROSSREGCPY(RBNameDst, RBNameSrc, Size) \ |
| do { \ |
| unsigned PartialMapDstIdx = PMI_##RBNameDst##Size - PMI_Min; \ |
| unsigned PartialMapSrcIdx = PMI_##RBNameSrc##Size - PMI_Min; \ |
| (void)PartialMapDstIdx; \ |
| (void)PartialMapSrcIdx; \ |
| const ValueMapping *Map = getCopyMapping( \ |
| AArch64::RBNameDst##RegBankID, AArch64::RBNameSrc##RegBankID, Size); \ |
| (void)Map; \ |
| assert(Map[0].BreakDown == \ |
| &AArch64GenRegisterBankInfo::PartMappings[PartialMapDstIdx] && \ |
| Map[0].NumBreakDowns == 1 && #RBNameDst #Size \ |
| " Dst is incorrectly initialized"); \ |
| assert(Map[1].BreakDown == \ |
| &AArch64GenRegisterBankInfo::PartMappings[PartialMapSrcIdx] && \ |
| Map[1].NumBreakDowns == 1 && #RBNameSrc #Size \ |
| " Src is incorrectly initialized"); \ |
| \ |
| } while (false) |
| |
| CHECK_VALUEMAP_CROSSREGCPY(GPR, GPR, 32); |
| CHECK_VALUEMAP_CROSSREGCPY(GPR, FPR, 32); |
| CHECK_VALUEMAP_CROSSREGCPY(GPR, GPR, 64); |
| CHECK_VALUEMAP_CROSSREGCPY(GPR, FPR, 64); |
| CHECK_VALUEMAP_CROSSREGCPY(FPR, FPR, 32); |
| CHECK_VALUEMAP_CROSSREGCPY(FPR, GPR, 32); |
| CHECK_VALUEMAP_CROSSREGCPY(FPR, FPR, 64); |
| CHECK_VALUEMAP_CROSSREGCPY(FPR, GPR, 64); |
| |
| #define CHECK_VALUEMAP_FPEXT(DstSize, SrcSize) \ |
| do { \ |
| unsigned PartialMapDstIdx = PMI_FPR##DstSize - PMI_Min; \ |
| unsigned PartialMapSrcIdx = PMI_FPR##SrcSize - PMI_Min; \ |
| (void)PartialMapDstIdx; \ |
| (void)PartialMapSrcIdx; \ |
| const ValueMapping *Map = getFPExtMapping(DstSize, SrcSize); \ |
| (void)Map; \ |
| assert(Map[0].BreakDown == \ |
| &AArch64GenRegisterBankInfo::PartMappings[PartialMapDstIdx] && \ |
| Map[0].NumBreakDowns == 1 && "FPR" #DstSize \ |
| " Dst is incorrectly initialized"); \ |
| assert(Map[1].BreakDown == \ |
| &AArch64GenRegisterBankInfo::PartMappings[PartialMapSrcIdx] && \ |
| Map[1].NumBreakDowns == 1 && "FPR" #SrcSize \ |
| " Src is incorrectly initialized"); \ |
| \ |
| } while (false) |
| |
| CHECK_VALUEMAP_FPEXT(32, 16); |
| CHECK_VALUEMAP_FPEXT(64, 16); |
| CHECK_VALUEMAP_FPEXT(64, 32); |
| CHECK_VALUEMAP_FPEXT(128, 64); |
| |
| assert(verify(TRI) && "Invalid register bank information"); |
| } |
| |
| unsigned AArch64RegisterBankInfo::copyCost(const RegisterBank &A, |
| const RegisterBank &B, |
| unsigned Size) const { |
| // What do we do with different size? |
| // copy are same size. |
| // Will introduce other hooks for different size: |
| // * extract cost. |
| // * build_sequence cost. |
| |
| // Copy from (resp. to) GPR to (resp. from) FPR involves FMOV. |
| // FIXME: This should be deduced from the scheduling model. |
| if (&A == &AArch64::GPRRegBank && &B == &AArch64::FPRRegBank) |
| // FMOVXDr or FMOVWSr. |
| return 5; |
| if (&A == &AArch64::FPRRegBank && &B == &AArch64::GPRRegBank) |
| // FMOVDXr or FMOVSWr. |
| return 4; |
| |
| return RegisterBankInfo::copyCost(A, B, Size); |
| } |
| |
| const RegisterBank & |
| AArch64RegisterBankInfo::getRegBankFromRegClass(const TargetRegisterClass &RC, |
| LLT) const { |
| switch (RC.getID()) { |
| case AArch64::FPR8RegClassID: |
| case AArch64::FPR16RegClassID: |
| case AArch64::FPR32RegClassID: |
| case AArch64::FPR64RegClassID: |
| case AArch64::FPR128RegClassID: |
| case AArch64::FPR128_loRegClassID: |
| case AArch64::DDRegClassID: |
| case AArch64::DDDRegClassID: |
| case AArch64::DDDDRegClassID: |
| case AArch64::QQRegClassID: |
| case AArch64::QQQRegClassID: |
| case AArch64::QQQQRegClassID: |
| return getRegBank(AArch64::FPRRegBankID); |
| case AArch64::GPR32commonRegClassID: |
| case AArch64::GPR32RegClassID: |
| case AArch64::GPR32spRegClassID: |
| case AArch64::GPR32sponlyRegClassID: |
| case AArch64::GPR32argRegClassID: |
| case AArch64::GPR32allRegClassID: |
| case AArch64::GPR64commonRegClassID: |
| case AArch64::GPR64RegClassID: |
| case AArch64::GPR64spRegClassID: |
| case AArch64::GPR64sponlyRegClassID: |
| case AArch64::GPR64argRegClassID: |
| case AArch64::GPR64allRegClassID: |
| case AArch64::GPR64noipRegClassID: |
| case AArch64::GPR64common_and_GPR64noipRegClassID: |
| case AArch64::GPR64noip_and_tcGPR64RegClassID: |
| case AArch64::tcGPR64RegClassID: |
| case AArch64::WSeqPairsClassRegClassID: |
| case AArch64::XSeqPairsClassRegClassID: |
| return getRegBank(AArch64::GPRRegBankID); |
| case AArch64::CCRRegClassID: |
| return getRegBank(AArch64::CCRegBankID); |
| default: |
| llvm_unreachable("Register class not supported"); |
| } |
| } |
| |
| RegisterBankInfo::InstructionMappings |
| AArch64RegisterBankInfo::getInstrAlternativeMappings( |
| const MachineInstr &MI) const { |
| const MachineFunction &MF = *MI.getParent()->getParent(); |
| const TargetSubtargetInfo &STI = MF.getSubtarget(); |
| const TargetRegisterInfo &TRI = *STI.getRegisterInfo(); |
| const MachineRegisterInfo &MRI = MF.getRegInfo(); |
| |
| switch (MI.getOpcode()) { |
| case TargetOpcode::G_OR: { |
| // 32 and 64-bit or can be mapped on either FPR or |
| // GPR for the same cost. |
| unsigned Size = getSizeInBits(MI.getOperand(0).getReg(), MRI, TRI); |
| if (Size != 32 && Size != 64) |
| break; |
| |
| // If the instruction has any implicit-defs or uses, |
| // do not mess with it. |
| if (MI.getNumOperands() != 3) |
| break; |
| InstructionMappings AltMappings; |
| const InstructionMapping &GPRMapping = getInstructionMapping( |
| /*ID*/ 1, /*Cost*/ 1, getValueMapping(PMI_FirstGPR, Size), |
| /*NumOperands*/ 3); |
| const InstructionMapping &FPRMapping = getInstructionMapping( |
| /*ID*/ 2, /*Cost*/ 1, getValueMapping(PMI_FirstFPR, Size), |
| /*NumOperands*/ 3); |
| |
| AltMappings.push_back(&GPRMapping); |
| AltMappings.push_back(&FPRMapping); |
| return AltMappings; |
| } |
| case TargetOpcode::G_BITCAST: { |
| unsigned Size = getSizeInBits(MI.getOperand(0).getReg(), MRI, TRI); |
| if (Size != 32 && Size != 64) |
| break; |
| |
| // If the instruction has any implicit-defs or uses, |
| // do not mess with it. |
| if (MI.getNumOperands() != 2) |
| break; |
| |
| InstructionMappings AltMappings; |
| const InstructionMapping &GPRMapping = getInstructionMapping( |
| /*ID*/ 1, /*Cost*/ 1, |
| getCopyMapping(AArch64::GPRRegBankID, AArch64::GPRRegBankID, Size), |
| /*NumOperands*/ 2); |
| const InstructionMapping &FPRMapping = getInstructionMapping( |
| /*ID*/ 2, /*Cost*/ 1, |
| getCopyMapping(AArch64::FPRRegBankID, AArch64::FPRRegBankID, Size), |
| /*NumOperands*/ 2); |
| const InstructionMapping &GPRToFPRMapping = getInstructionMapping( |
| /*ID*/ 3, |
| /*Cost*/ copyCost(AArch64::GPRRegBank, AArch64::FPRRegBank, Size), |
| getCopyMapping(AArch64::FPRRegBankID, AArch64::GPRRegBankID, Size), |
| /*NumOperands*/ 2); |
| const InstructionMapping &FPRToGPRMapping = getInstructionMapping( |
| /*ID*/ 3, |
| /*Cost*/ copyCost(AArch64::GPRRegBank, AArch64::FPRRegBank, Size), |
| getCopyMapping(AArch64::GPRRegBankID, AArch64::FPRRegBankID, Size), |
| /*NumOperands*/ 2); |
| |
| AltMappings.push_back(&GPRMapping); |
| AltMappings.push_back(&FPRMapping); |
| AltMappings.push_back(&GPRToFPRMapping); |
| AltMappings.push_back(&FPRToGPRMapping); |
| return AltMappings; |
| } |
| case TargetOpcode::G_LOAD: { |
| unsigned Size = getSizeInBits(MI.getOperand(0).getReg(), MRI, TRI); |
| if (Size != 64) |
| break; |
| |
| // If the instruction has any implicit-defs or uses, |
| // do not mess with it. |
| if (MI.getNumOperands() != 2) |
| break; |
| |
| InstructionMappings AltMappings; |
| const InstructionMapping &GPRMapping = getInstructionMapping( |
| /*ID*/ 1, /*Cost*/ 1, |
| getOperandsMapping({getValueMapping(PMI_FirstGPR, Size), |
| // Addresses are GPR 64-bit. |
| getValueMapping(PMI_FirstGPR, 64)}), |
| /*NumOperands*/ 2); |
| const InstructionMapping &FPRMapping = getInstructionMapping( |
| /*ID*/ 2, /*Cost*/ 1, |
| getOperandsMapping({getValueMapping(PMI_FirstFPR, Size), |
| // Addresses are GPR 64-bit. |
| getValueMapping(PMI_FirstGPR, 64)}), |
| /*NumOperands*/ 2); |
| |
| AltMappings.push_back(&GPRMapping); |
| AltMappings.push_back(&FPRMapping); |
| return AltMappings; |
| } |
| default: |
| break; |
| } |
| return RegisterBankInfo::getInstrAlternativeMappings(MI); |
| } |
| |
| void AArch64RegisterBankInfo::applyMappingImpl( |
| const OperandsMapper &OpdMapper) const { |
| switch (OpdMapper.getMI().getOpcode()) { |
| case TargetOpcode::G_OR: |
| case TargetOpcode::G_BITCAST: |
| case TargetOpcode::G_LOAD: |
| // Those ID must match getInstrAlternativeMappings. |
| assert((OpdMapper.getInstrMapping().getID() >= 1 && |
| OpdMapper.getInstrMapping().getID() <= 4) && |
| "Don't know how to handle that ID"); |
| return applyDefaultMapping(OpdMapper); |
| default: |
| llvm_unreachable("Don't know how to handle that operation"); |
| } |
| } |
| |
| /// Returns whether opcode \p Opc is a pre-isel generic floating-point opcode, |
| /// having only floating-point operands. |
| static bool isPreISelGenericFloatingPointOpcode(unsigned Opc) { |
| switch (Opc) { |
| case TargetOpcode::G_FADD: |
| case TargetOpcode::G_FSUB: |
| case TargetOpcode::G_FMUL: |
| case TargetOpcode::G_FMA: |
| case TargetOpcode::G_FDIV: |
| case TargetOpcode::G_FCONSTANT: |
| case TargetOpcode::G_FPEXT: |
| case TargetOpcode::G_FPTRUNC: |
| case TargetOpcode::G_FCEIL: |
| case TargetOpcode::G_FFLOOR: |
| case TargetOpcode::G_FNEARBYINT: |
| case TargetOpcode::G_FNEG: |
| case TargetOpcode::G_FCOS: |
| case TargetOpcode::G_FSIN: |
| case TargetOpcode::G_FLOG10: |
| case TargetOpcode::G_FLOG: |
| case TargetOpcode::G_FLOG2: |
| case TargetOpcode::G_FSQRT: |
| case TargetOpcode::G_FABS: |
| case TargetOpcode::G_FEXP: |
| case TargetOpcode::G_FRINT: |
| case TargetOpcode::G_INTRINSIC_TRUNC: |
| case TargetOpcode::G_INTRINSIC_ROUND: |
| return true; |
| } |
| return false; |
| } |
| |
| const RegisterBankInfo::InstructionMapping & |
| AArch64RegisterBankInfo::getSameKindOfOperandsMapping( |
| const MachineInstr &MI) const { |
| const unsigned Opc = MI.getOpcode(); |
| const MachineFunction &MF = *MI.getParent()->getParent(); |
| const MachineRegisterInfo &MRI = MF.getRegInfo(); |
| |
| unsigned NumOperands = MI.getNumOperands(); |
| assert(NumOperands <= 3 && |
| "This code is for instructions with 3 or less operands"); |
| |
| LLT Ty = MRI.getType(MI.getOperand(0).getReg()); |
| unsigned Size = Ty.getSizeInBits(); |
| bool IsFPR = Ty.isVector() || isPreISelGenericFloatingPointOpcode(Opc); |
| |
| PartialMappingIdx RBIdx = IsFPR ? PMI_FirstFPR : PMI_FirstGPR; |
| |
| #ifndef NDEBUG |
| // Make sure all the operands are using similar size and type. |
| // Should probably be checked by the machine verifier. |
| // This code won't catch cases where the number of lanes is |
| // different between the operands. |
| // If we want to go to that level of details, it is probably |
| // best to check that the types are the same, period. |
| // Currently, we just check that the register banks are the same |
| // for each types. |
| for (unsigned Idx = 1; Idx != NumOperands; ++Idx) { |
| LLT OpTy = MRI.getType(MI.getOperand(Idx).getReg()); |
| assert( |
| AArch64GenRegisterBankInfo::getRegBankBaseIdxOffset( |
| RBIdx, OpTy.getSizeInBits()) == |
| AArch64GenRegisterBankInfo::getRegBankBaseIdxOffset(RBIdx, Size) && |
| "Operand has incompatible size"); |
| bool OpIsFPR = OpTy.isVector() || isPreISelGenericFloatingPointOpcode(Opc); |
| (void)OpIsFPR; |
| assert(IsFPR == OpIsFPR && "Operand has incompatible type"); |
| } |
| #endif // End NDEBUG. |
| |
| return getInstructionMapping(DefaultMappingID, 1, |
| getValueMapping(RBIdx, Size), NumOperands); |
| } |
| |
| bool AArch64RegisterBankInfo::hasFPConstraints( |
| const MachineInstr &MI, const MachineRegisterInfo &MRI, |
| const TargetRegisterInfo &TRI) const { |
| unsigned Op = MI.getOpcode(); |
| |
| // Do we have an explicit floating point instruction? |
| if (isPreISelGenericFloatingPointOpcode(Op)) |
| return true; |
| |
| // No. Check if we have a copy-like instruction. If we do, then we could |
| // still be fed by floating point instructions. |
| if (Op != TargetOpcode::COPY && !MI.isPHI()) |
| return false; |
| |
| // MI is copy-like. Return true if it outputs an FPR. |
| return getRegBank(MI.getOperand(0).getReg(), MRI, TRI) == |
| &AArch64::FPRRegBank; |
| } |
| |
| bool AArch64RegisterBankInfo::onlyUsesFP(const MachineInstr &MI, |
| const MachineRegisterInfo &MRI, |
| const TargetRegisterInfo &TRI) const { |
| switch (MI.getOpcode()) { |
| case TargetOpcode::G_FPTOSI: |
| case TargetOpcode::G_FPTOUI: |
| case TargetOpcode::G_FCMP: |
| return true; |
| default: |
| break; |
| } |
| return hasFPConstraints(MI, MRI, TRI); |
| } |
| |
| bool AArch64RegisterBankInfo::onlyDefinesFP( |
| const MachineInstr &MI, const MachineRegisterInfo &MRI, |
| const TargetRegisterInfo &TRI) const { |
| switch (MI.getOpcode()) { |
| case TargetOpcode::G_SITOFP: |
| case TargetOpcode::G_UITOFP: |
| case TargetOpcode::G_EXTRACT_VECTOR_ELT: |
| case TargetOpcode::G_INSERT_VECTOR_ELT: |
| return true; |
| default: |
| break; |
| } |
| return hasFPConstraints(MI, MRI, TRI); |
| } |
| |
| const RegisterBankInfo::InstructionMapping & |
| AArch64RegisterBankInfo::getInstrMapping(const MachineInstr &MI) const { |
| const unsigned Opc = MI.getOpcode(); |
| |
| // Try the default logic for non-generic instructions that are either copies |
| // or already have some operands assigned to banks. |
| if ((Opc != TargetOpcode::COPY && !isPreISelGenericOpcode(Opc)) || |
| Opc == TargetOpcode::G_PHI) { |
| const RegisterBankInfo::InstructionMapping &Mapping = |
| getInstrMappingImpl(MI); |
| if (Mapping.isValid()) |
| return Mapping; |
| } |
| |
| const MachineFunction &MF = *MI.getParent()->getParent(); |
| const MachineRegisterInfo &MRI = MF.getRegInfo(); |
| const TargetSubtargetInfo &STI = MF.getSubtarget(); |
| const TargetRegisterInfo &TRI = *STI.getRegisterInfo(); |
| |
| switch (Opc) { |
| // G_{F|S|U}REM are not listed because they are not legal. |
| // Arithmetic ops. |
| case TargetOpcode::G_ADD: |
| case TargetOpcode::G_SUB: |
| case TargetOpcode::G_PTR_ADD: |
| case TargetOpcode::G_MUL: |
| case TargetOpcode::G_SDIV: |
| case TargetOpcode::G_UDIV: |
| // Bitwise ops. |
| case TargetOpcode::G_AND: |
| case TargetOpcode::G_OR: |
| case TargetOpcode::G_XOR: |
| // Floating point ops. |
| case TargetOpcode::G_FADD: |
| case TargetOpcode::G_FSUB: |
| case TargetOpcode::G_FMUL: |
| case TargetOpcode::G_FDIV: |
| return getSameKindOfOperandsMapping(MI); |
| case TargetOpcode::G_FPEXT: { |
| LLT DstTy = MRI.getType(MI.getOperand(0).getReg()); |
| LLT SrcTy = MRI.getType(MI.getOperand(1).getReg()); |
| return getInstructionMapping( |
| DefaultMappingID, /*Cost*/ 1, |
| getFPExtMapping(DstTy.getSizeInBits(), SrcTy.getSizeInBits()), |
| /*NumOperands*/ 2); |
| } |
| // Shifts. |
| case TargetOpcode::G_SHL: |
| case TargetOpcode::G_LSHR: |
| case TargetOpcode::G_ASHR: { |
| LLT ShiftAmtTy = MRI.getType(MI.getOperand(2).getReg()); |
| LLT SrcTy = MRI.getType(MI.getOperand(1).getReg()); |
| if (ShiftAmtTy.getSizeInBits() == 64 && SrcTy.getSizeInBits() == 32) |
| return getInstructionMapping(DefaultMappingID, 1, |
| &ValMappings[Shift64Imm], 3); |
| return getSameKindOfOperandsMapping(MI); |
| } |
| case TargetOpcode::COPY: { |
| Register DstReg = MI.getOperand(0).getReg(); |
| Register SrcReg = MI.getOperand(1).getReg(); |
| // Check if one of the register is not a generic register. |
| if ((Register::isPhysicalRegister(DstReg) || |
| !MRI.getType(DstReg).isValid()) || |
| (Register::isPhysicalRegister(SrcReg) || |
| !MRI.getType(SrcReg).isValid())) { |
| const RegisterBank *DstRB = getRegBank(DstReg, MRI, TRI); |
| const RegisterBank *SrcRB = getRegBank(SrcReg, MRI, TRI); |
| if (!DstRB) |
| DstRB = SrcRB; |
| else if (!SrcRB) |
| SrcRB = DstRB; |
| // If both RB are null that means both registers are generic. |
| // We shouldn't be here. |
| assert(DstRB && SrcRB && "Both RegBank were nullptr"); |
| unsigned Size = getSizeInBits(DstReg, MRI, TRI); |
| return getInstructionMapping( |
| DefaultMappingID, copyCost(*DstRB, *SrcRB, Size), |
| getCopyMapping(DstRB->getID(), SrcRB->getID(), Size), |
| // We only care about the mapping of the destination. |
| /*NumOperands*/ 1); |
| } |
| // Both registers are generic, use G_BITCAST. |
| LLVM_FALLTHROUGH; |
| } |
| case TargetOpcode::G_BITCAST: { |
| LLT DstTy = MRI.getType(MI.getOperand(0).getReg()); |
| LLT SrcTy = MRI.getType(MI.getOperand(1).getReg()); |
| unsigned Size = DstTy.getSizeInBits(); |
| bool DstIsGPR = !DstTy.isVector() && DstTy.getSizeInBits() <= 64; |
| bool SrcIsGPR = !SrcTy.isVector() && SrcTy.getSizeInBits() <= 64; |
| const RegisterBank &DstRB = |
| DstIsGPR ? AArch64::GPRRegBank : AArch64::FPRRegBank; |
| const RegisterBank &SrcRB = |
| SrcIsGPR ? AArch64::GPRRegBank : AArch64::FPRRegBank; |
| return getInstructionMapping( |
| DefaultMappingID, copyCost(DstRB, SrcRB, Size), |
| getCopyMapping(DstRB.getID(), SrcRB.getID(), Size), |
| // We only care about the mapping of the destination for COPY. |
| /*NumOperands*/ Opc == TargetOpcode::G_BITCAST ? 2 : 1); |
| } |
| default: |
| break; |
| } |
| |
| unsigned NumOperands = MI.getNumOperands(); |
| |
| // Track the size and bank of each register. We don't do partial mappings. |
| SmallVector<unsigned, 4> OpSize(NumOperands); |
| SmallVector<PartialMappingIdx, 4> OpRegBankIdx(NumOperands); |
| for (unsigned Idx = 0; Idx < NumOperands; ++Idx) { |
| auto &MO = MI.getOperand(Idx); |
| if (!MO.isReg() || !MO.getReg()) |
| continue; |
| |
| LLT Ty = MRI.getType(MO.getReg()); |
| OpSize[Idx] = Ty.getSizeInBits(); |
| |
| // As a top-level guess, vectors go in FPRs, scalars and pointers in GPRs. |
| // For floating-point instructions, scalars go in FPRs. |
| if (Ty.isVector() || isPreISelGenericFloatingPointOpcode(Opc) || |
| Ty.getSizeInBits() > 64) |
| OpRegBankIdx[Idx] = PMI_FirstFPR; |
| else |
| OpRegBankIdx[Idx] = PMI_FirstGPR; |
| } |
| |
| unsigned Cost = 1; |
| // Some of the floating-point instructions have mixed GPR and FPR operands: |
| // fine-tune the computed mapping. |
| switch (Opc) { |
| case TargetOpcode::G_TRUNC: { |
| LLT SrcTy = MRI.getType(MI.getOperand(1).getReg()); |
| if (!SrcTy.isVector() && SrcTy.getSizeInBits() == 128) |
| OpRegBankIdx = {PMI_FirstFPR, PMI_FirstFPR}; |
| break; |
| } |
| case TargetOpcode::G_SITOFP: |
| case TargetOpcode::G_UITOFP: |
| if (MRI.getType(MI.getOperand(0).getReg()).isVector()) |
| break; |
| OpRegBankIdx = {PMI_FirstFPR, PMI_FirstGPR}; |
| break; |
| case TargetOpcode::G_FPTOSI: |
| case TargetOpcode::G_FPTOUI: |
| if (MRI.getType(MI.getOperand(0).getReg()).isVector()) |
| break; |
| OpRegBankIdx = {PMI_FirstGPR, PMI_FirstFPR}; |
| break; |
| case TargetOpcode::G_FCMP: |
| OpRegBankIdx = {PMI_FirstGPR, |
| /* Predicate */ PMI_None, PMI_FirstFPR, PMI_FirstFPR}; |
| break; |
| case TargetOpcode::G_BITCAST: |
| // This is going to be a cross register bank copy and this is expensive. |
| if (OpRegBankIdx[0] != OpRegBankIdx[1]) |
| Cost = copyCost( |
| *AArch64GenRegisterBankInfo::PartMappings[OpRegBankIdx[0]].RegBank, |
| *AArch64GenRegisterBankInfo::PartMappings[OpRegBankIdx[1]].RegBank, |
| OpSize[0]); |
| break; |
| case TargetOpcode::G_LOAD: |
| // Loading in vector unit is slightly more expensive. |
| // This is actually only true for the LD1R and co instructions, |
| // but anyway for the fast mode this number does not matter and |
| // for the greedy mode the cost of the cross bank copy will |
| // offset this number. |
| // FIXME: Should be derived from the scheduling model. |
| if (OpRegBankIdx[0] != PMI_FirstGPR) |
| Cost = 2; |
| else |
| // Check if that load feeds fp instructions. |
| // In that case, we want the default mapping to be on FPR |
| // instead of blind map every scalar to GPR. |
| for (const MachineInstr &UseMI : |
| MRI.use_instructions(MI.getOperand(0).getReg())) { |
| // If we have at least one direct use in a FP instruction, |
| // assume this was a floating point load in the IR. |
| // If it was not, we would have had a bitcast before |
| // reaching that instruction. |
| if (onlyUsesFP(UseMI, MRI, TRI)) { |
| OpRegBankIdx[0] = PMI_FirstFPR; |
| break; |
| } |
| } |
| break; |
| case TargetOpcode::G_STORE: |
| // Check if that store is fed by fp instructions. |
| if (OpRegBankIdx[0] == PMI_FirstGPR) { |
| Register VReg = MI.getOperand(0).getReg(); |
| if (!VReg) |
| break; |
| MachineInstr *DefMI = MRI.getVRegDef(VReg); |
| if (onlyDefinesFP(*DefMI, MRI, TRI)) |
| OpRegBankIdx[0] = PMI_FirstFPR; |
| break; |
| } |
| break; |
| case TargetOpcode::G_SELECT: { |
| // If the destination is FPR, preserve that. |
| if (OpRegBankIdx[0] != PMI_FirstGPR) |
| break; |
| |
| // If we're taking in vectors, we have no choice but to put everything on |
| // FPRs, except for the condition. The condition must always be on a GPR. |
| LLT SrcTy = MRI.getType(MI.getOperand(2).getReg()); |
| if (SrcTy.isVector()) { |
| OpRegBankIdx = {PMI_FirstFPR, PMI_FirstGPR, PMI_FirstFPR, PMI_FirstFPR}; |
| break; |
| } |
| |
| // Try to minimize the number of copies. If we have more floating point |
| // constrained values than not, then we'll put everything on FPR. Otherwise, |
| // everything has to be on GPR. |
| unsigned NumFP = 0; |
| |
| // Check if the uses of the result always produce floating point values. |
| // |
| // For example: |
| // |
| // %z = G_SELECT %cond %x %y |
| // fpr = G_FOO %z ... |
| if (any_of( |
| MRI.use_instructions(MI.getOperand(0).getReg()), |
| [&](MachineInstr &MI) { return onlyUsesFP(MI, MRI, TRI); })) |
| ++NumFP; |
| |
| // Check if the defs of the source values always produce floating point |
| // values. |
| // |
| // For example: |
| // |
| // %x = G_SOMETHING_ALWAYS_FLOAT %a ... |
| // %z = G_SELECT %cond %x %y |
| // |
| // Also check whether or not the sources have already been decided to be |
| // FPR. Keep track of this. |
| // |
| // This doesn't check the condition, since it's just whatever is in NZCV. |
| // This isn't passed explicitly in a register to fcsel/csel. |
| for (unsigned Idx = 2; Idx < 4; ++Idx) { |
| Register VReg = MI.getOperand(Idx).getReg(); |
| MachineInstr *DefMI = MRI.getVRegDef(VReg); |
| if (getRegBank(VReg, MRI, TRI) == &AArch64::FPRRegBank || |
| onlyDefinesFP(*DefMI, MRI, TRI)) |
| ++NumFP; |
| } |
| |
| // If we have more FP constraints than not, then move everything over to |
| // FPR. |
| if (NumFP >= 2) |
| OpRegBankIdx = {PMI_FirstFPR, PMI_FirstGPR, PMI_FirstFPR, PMI_FirstFPR}; |
| |
| break; |
| } |
| case TargetOpcode::G_UNMERGE_VALUES: { |
| // If the first operand belongs to a FPR register bank, then make sure that |
| // we preserve that. |
| if (OpRegBankIdx[0] != PMI_FirstGPR) |
| break; |
| |
| LLT SrcTy = MRI.getType(MI.getOperand(MI.getNumOperands()-1).getReg()); |
| // UNMERGE into scalars from a vector should always use FPR. |
| // Likewise if any of the uses are FP instructions. |
| if (SrcTy.isVector() || SrcTy == LLT::scalar(128) || |
| any_of(MRI.use_instructions(MI.getOperand(0).getReg()), |
| [&](MachineInstr &MI) { return onlyUsesFP(MI, MRI, TRI); })) { |
| // Set the register bank of every operand to FPR. |
| for (unsigned Idx = 0, NumOperands = MI.getNumOperands(); |
| Idx < NumOperands; ++Idx) |
| OpRegBankIdx[Idx] = PMI_FirstFPR; |
| } |
| break; |
| } |
| case TargetOpcode::G_EXTRACT_VECTOR_ELT: |
| // Destination and source need to be FPRs. |
| OpRegBankIdx[0] = PMI_FirstFPR; |
| OpRegBankIdx[1] = PMI_FirstFPR; |
| |
| // Index needs to be a GPR. |
| OpRegBankIdx[2] = PMI_FirstGPR; |
| break; |
| case TargetOpcode::G_INSERT_VECTOR_ELT: |
| OpRegBankIdx[0] = PMI_FirstFPR; |
| OpRegBankIdx[1] = PMI_FirstFPR; |
| |
| // The element may be either a GPR or FPR. Preserve that behaviour. |
| if (getRegBank(MI.getOperand(2).getReg(), MRI, TRI) == &AArch64::FPRRegBank) |
| OpRegBankIdx[2] = PMI_FirstFPR; |
| else |
| OpRegBankIdx[2] = PMI_FirstGPR; |
| |
| // Index needs to be a GPR. |
| OpRegBankIdx[3] = PMI_FirstGPR; |
| break; |
| case TargetOpcode::G_EXTRACT: { |
| // For s128 sources we have to use fpr. |
| LLT SrcTy = MRI.getType(MI.getOperand(1).getReg()); |
| if (SrcTy.getSizeInBits() == 128) { |
| OpRegBankIdx[0] = PMI_FirstFPR; |
| OpRegBankIdx[1] = PMI_FirstFPR; |
| } |
| break; |
| } |
| case TargetOpcode::G_BUILD_VECTOR: |
| // If the first source operand belongs to a FPR register bank, then make |
| // sure that we preserve that. |
| if (OpRegBankIdx[1] != PMI_FirstGPR) |
| break; |
| Register VReg = MI.getOperand(1).getReg(); |
| if (!VReg) |
| break; |
| |
| // Get the instruction that defined the source operand reg, and check if |
| // it's a floating point operation. Or, if it's a type like s16 which |
| // doesn't have a exact size gpr register class. |
| MachineInstr *DefMI = MRI.getVRegDef(VReg); |
| unsigned DefOpc = DefMI->getOpcode(); |
| const LLT SrcTy = MRI.getType(VReg); |
| if (isPreISelGenericFloatingPointOpcode(DefOpc) || |
| SrcTy.getSizeInBits() < 32) { |
| // Have a floating point op. |
| // Make sure every operand gets mapped to a FPR register class. |
| unsigned NumOperands = MI.getNumOperands(); |
| for (unsigned Idx = 0; Idx < NumOperands; ++Idx) |
| OpRegBankIdx[Idx] = PMI_FirstFPR; |
| } |
| break; |
| } |
| |
| // Finally construct the computed mapping. |
| SmallVector<const ValueMapping *, 8> OpdsMapping(NumOperands); |
| for (unsigned Idx = 0; Idx < NumOperands; ++Idx) { |
| if (MI.getOperand(Idx).isReg() && MI.getOperand(Idx).getReg()) { |
| auto Mapping = getValueMapping(OpRegBankIdx[Idx], OpSize[Idx]); |
| if (!Mapping->isValid()) |
| return getInvalidInstructionMapping(); |
| |
| OpdsMapping[Idx] = Mapping; |
| } |
| } |
| |
| return getInstructionMapping(DefaultMappingID, Cost, |
| getOperandsMapping(OpdsMapping), NumOperands); |
| } |
