| //===- AArch64InstrInfo.h - AArch64 Instruction Information -----*- C++ -*-===// |
| // |
| // 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 |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file contains the AArch64 implementation of the TargetInstrInfo class. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef LLVM_LIB_TARGET_AARCH64_AARCH64INSTRINFO_H |
| #define LLVM_LIB_TARGET_AARCH64_AARCH64INSTRINFO_H |
| |
| #include "AArch64.h" |
| #include "AArch64RegisterInfo.h" |
| #include "AArch64StackOffset.h" |
| #include "llvm/ADT/Optional.h" |
| #include "llvm/CodeGen/MachineCombinerPattern.h" |
| #include "llvm/CodeGen/TargetInstrInfo.h" |
| |
| #define GET_INSTRINFO_HEADER |
| #include "AArch64GenInstrInfo.inc" |
| |
| namespace llvm { |
| |
| class AArch64Subtarget; |
| class AArch64TargetMachine; |
| |
| static const MachineMemOperand::Flags MOSuppressPair = |
| MachineMemOperand::MOTargetFlag1; |
| static const MachineMemOperand::Flags MOStridedAccess = |
| MachineMemOperand::MOTargetFlag2; |
| |
| #define FALKOR_STRIDED_ACCESS_MD "falkor.strided.access" |
| |
| class AArch64InstrInfo final : public AArch64GenInstrInfo { |
| const AArch64RegisterInfo RI; |
| const AArch64Subtarget &Subtarget; |
| |
| public: |
| explicit AArch64InstrInfo(const AArch64Subtarget &STI); |
| |
| /// getRegisterInfo - TargetInstrInfo is a superset of MRegister info. As |
| /// such, whenever a client has an instance of instruction info, it should |
| /// always be able to get register info as well (through this method). |
| const AArch64RegisterInfo &getRegisterInfo() const { return RI; } |
| |
| unsigned getInstSizeInBytes(const MachineInstr &MI) const override; |
| |
| bool isAsCheapAsAMove(const MachineInstr &MI) const override; |
| |
| bool isCoalescableExtInstr(const MachineInstr &MI, unsigned &SrcReg, |
| unsigned &DstReg, unsigned &SubIdx) const override; |
| |
| bool |
| areMemAccessesTriviallyDisjoint(const MachineInstr &MIa, |
| const MachineInstr &MIb) const override; |
| |
| unsigned isLoadFromStackSlot(const MachineInstr &MI, |
| int &FrameIndex) const override; |
| unsigned isStoreToStackSlot(const MachineInstr &MI, |
| int &FrameIndex) const override; |
| |
| /// Does this instruction set its full destination register to zero? |
| static bool isGPRZero(const MachineInstr &MI); |
| |
| /// Does this instruction rename a GPR without modifying bits? |
| static bool isGPRCopy(const MachineInstr &MI); |
| |
| /// Does this instruction rename an FPR without modifying bits? |
| static bool isFPRCopy(const MachineInstr &MI); |
| |
| /// Return true if pairing the given load or store is hinted to be |
| /// unprofitable. |
| static bool isLdStPairSuppressed(const MachineInstr &MI); |
| |
| /// Return true if the given load or store is a strided memory access. |
| static bool isStridedAccess(const MachineInstr &MI); |
| |
| /// Return true if this is an unscaled load/store. |
| static bool isUnscaledLdSt(unsigned Opc); |
| static bool isUnscaledLdSt(MachineInstr &MI) { |
| return isUnscaledLdSt(MI.getOpcode()); |
| } |
| |
| /// Returns the unscaled load/store for the scaled load/store opcode, |
| /// if there is a corresponding unscaled variant available. |
| static Optional<unsigned> getUnscaledLdSt(unsigned Opc); |
| |
| |
| /// Returns the index for the immediate for a given instruction. |
| static unsigned getLoadStoreImmIdx(unsigned Opc); |
| |
| /// Return true if pairing the given load or store may be paired with another. |
| static bool isPairableLdStInst(const MachineInstr &MI); |
| |
| /// Return the opcode that set flags when possible. The caller is |
| /// responsible for ensuring the opc has a flag setting equivalent. |
| static unsigned convertToFlagSettingOpc(unsigned Opc, bool &Is64Bit); |
| |
| /// Return true if this is a load/store that can be potentially paired/merged. |
| bool isCandidateToMergeOrPair(const MachineInstr &MI) const; |
| |
| /// Hint that pairing the given load or store is unprofitable. |
| static void suppressLdStPair(MachineInstr &MI); |
| |
| bool getMemOperandWithOffset(const MachineInstr &MI, |
| const MachineOperand *&BaseOp, |
| int64_t &Offset, |
| const TargetRegisterInfo *TRI) const override; |
| |
| bool getMemOperandWithOffsetWidth(const MachineInstr &MI, |
| const MachineOperand *&BaseOp, |
| int64_t &Offset, unsigned &Width, |
| const TargetRegisterInfo *TRI) const; |
| |
| /// Return the immediate offset of the base register in a load/store \p LdSt. |
| MachineOperand &getMemOpBaseRegImmOfsOffsetOperand(MachineInstr &LdSt) const; |
| |
| /// Returns true if opcode \p Opc is a memory operation. If it is, set |
| /// \p Scale, \p Width, \p MinOffset, and \p MaxOffset accordingly. |
| /// |
| /// For unscaled instructions, \p Scale is set to 1. |
| static bool getMemOpInfo(unsigned Opcode, unsigned &Scale, unsigned &Width, |
| int64_t &MinOffset, int64_t &MaxOffset); |
| |
| bool shouldClusterMemOps(const MachineOperand &BaseOp1, |
| const MachineOperand &BaseOp2, |
| unsigned NumLoads) const override; |
| |
| void copyPhysRegTuple(MachineBasicBlock &MBB, MachineBasicBlock::iterator I, |
| const DebugLoc &DL, unsigned DestReg, unsigned SrcReg, |
| bool KillSrc, unsigned Opcode, |
| llvm::ArrayRef<unsigned> Indices) const; |
| void copyGPRRegTuple(MachineBasicBlock &MBB, MachineBasicBlock::iterator I, |
| DebugLoc DL, unsigned DestReg, unsigned SrcReg, |
| bool KillSrc, unsigned Opcode, unsigned ZeroReg, |
| llvm::ArrayRef<unsigned> Indices) const; |
| void copyPhysReg(MachineBasicBlock &MBB, MachineBasicBlock::iterator I, |
| const DebugLoc &DL, unsigned DestReg, unsigned SrcReg, |
| bool KillSrc) const override; |
| |
| void storeRegToStackSlot(MachineBasicBlock &MBB, |
| MachineBasicBlock::iterator MBBI, unsigned SrcReg, |
| bool isKill, int FrameIndex, |
| const TargetRegisterClass *RC, |
| const TargetRegisterInfo *TRI) const override; |
| |
| void loadRegFromStackSlot(MachineBasicBlock &MBB, |
| MachineBasicBlock::iterator MBBI, unsigned DestReg, |
| int FrameIndex, const TargetRegisterClass *RC, |
| const TargetRegisterInfo *TRI) const override; |
| |
| // This tells target independent code that it is okay to pass instructions |
| // with subreg operands to foldMemoryOperandImpl. |
| bool isSubregFoldable() const override { return true; } |
| |
| using TargetInstrInfo::foldMemoryOperandImpl; |
| MachineInstr * |
| foldMemoryOperandImpl(MachineFunction &MF, MachineInstr &MI, |
| ArrayRef<unsigned> Ops, |
| MachineBasicBlock::iterator InsertPt, int FrameIndex, |
| LiveIntervals *LIS = nullptr, |
| VirtRegMap *VRM = nullptr) const override; |
| |
| /// \returns true if a branch from an instruction with opcode \p BranchOpc |
| /// bytes is capable of jumping to a position \p BrOffset bytes away. |
| bool isBranchOffsetInRange(unsigned BranchOpc, |
| int64_t BrOffset) const override; |
| |
| MachineBasicBlock *getBranchDestBlock(const MachineInstr &MI) const override; |
| |
| bool analyzeBranch(MachineBasicBlock &MBB, MachineBasicBlock *&TBB, |
| MachineBasicBlock *&FBB, |
| SmallVectorImpl<MachineOperand> &Cond, |
| bool AllowModify = false) const override; |
| unsigned removeBranch(MachineBasicBlock &MBB, |
| int *BytesRemoved = nullptr) const override; |
| unsigned insertBranch(MachineBasicBlock &MBB, MachineBasicBlock *TBB, |
| MachineBasicBlock *FBB, ArrayRef<MachineOperand> Cond, |
| const DebugLoc &DL, |
| int *BytesAdded = nullptr) const override; |
| bool |
| reverseBranchCondition(SmallVectorImpl<MachineOperand> &Cond) const override; |
| bool canInsertSelect(const MachineBasicBlock &, ArrayRef<MachineOperand> Cond, |
| unsigned, unsigned, int &, int &, int &) const override; |
| void insertSelect(MachineBasicBlock &MBB, MachineBasicBlock::iterator MI, |
| const DebugLoc &DL, unsigned DstReg, |
| ArrayRef<MachineOperand> Cond, unsigned TrueReg, |
| unsigned FalseReg) const override; |
| void getNoop(MCInst &NopInst) const override; |
| |
| bool isSchedulingBoundary(const MachineInstr &MI, |
| const MachineBasicBlock *MBB, |
| const MachineFunction &MF) const override; |
| |
| /// analyzeCompare - For a comparison instruction, return the source registers |
| /// in SrcReg and SrcReg2, and the value it compares against in CmpValue. |
| /// Return true if the comparison instruction can be analyzed. |
| bool analyzeCompare(const MachineInstr &MI, unsigned &SrcReg, |
| unsigned &SrcReg2, int &CmpMask, |
| int &CmpValue) const override; |
| /// optimizeCompareInstr - Convert the instruction supplying the argument to |
| /// the comparison into one that sets the zero bit in the flags register. |
| bool optimizeCompareInstr(MachineInstr &CmpInstr, unsigned SrcReg, |
| unsigned SrcReg2, int CmpMask, int CmpValue, |
| const MachineRegisterInfo *MRI) const override; |
| bool optimizeCondBranch(MachineInstr &MI) const override; |
| |
| /// Return true when a code sequence can improve throughput. It |
| /// should be called only for instructions in loops. |
| /// \param Pattern - combiner pattern |
| bool isThroughputPattern(MachineCombinerPattern Pattern) const override; |
| /// Return true when there is potentially a faster code sequence |
| /// for an instruction chain ending in ``Root``. All potential patterns are |
| /// listed in the ``Patterns`` array. |
| bool getMachineCombinerPatterns( |
| MachineInstr &Root, |
| SmallVectorImpl<MachineCombinerPattern> &Patterns) const override; |
| /// Return true when Inst is associative and commutative so that it can be |
| /// reassociated. |
| bool isAssociativeAndCommutative(const MachineInstr &Inst) const override; |
| /// When getMachineCombinerPatterns() finds patterns, this function generates |
| /// the instructions that could replace the original code sequence |
| void genAlternativeCodeSequence( |
| MachineInstr &Root, MachineCombinerPattern Pattern, |
| SmallVectorImpl<MachineInstr *> &InsInstrs, |
| SmallVectorImpl<MachineInstr *> &DelInstrs, |
| DenseMap<unsigned, unsigned> &InstrIdxForVirtReg) const override; |
| /// AArch64 supports MachineCombiner. |
| bool useMachineCombiner() const override; |
| |
| bool expandPostRAPseudo(MachineInstr &MI) const override; |
| |
| std::pair<unsigned, unsigned> |
| decomposeMachineOperandsTargetFlags(unsigned TF) const override; |
| ArrayRef<std::pair<unsigned, const char *>> |
| getSerializableDirectMachineOperandTargetFlags() const override; |
| ArrayRef<std::pair<unsigned, const char *>> |
| getSerializableBitmaskMachineOperandTargetFlags() const override; |
| ArrayRef<std::pair<MachineMemOperand::Flags, const char *>> |
| getSerializableMachineMemOperandTargetFlags() const override; |
| |
| bool isFunctionSafeToOutlineFrom(MachineFunction &MF, |
| bool OutlineFromLinkOnceODRs) const override; |
| outliner::OutlinedFunction getOutliningCandidateInfo( |
| std::vector<outliner::Candidate> &RepeatedSequenceLocs) const override; |
| outliner::InstrType |
| getOutliningType(MachineBasicBlock::iterator &MIT, unsigned Flags) const override; |
| bool isMBBSafeToOutlineFrom(MachineBasicBlock &MBB, |
| unsigned &Flags) const override; |
| void buildOutlinedFrame(MachineBasicBlock &MBB, MachineFunction &MF, |
| const outliner::OutlinedFunction &OF) const override; |
| MachineBasicBlock::iterator |
| insertOutlinedCall(Module &M, MachineBasicBlock &MBB, |
| MachineBasicBlock::iterator &It, MachineFunction &MF, |
| const outliner::Candidate &C) const override; |
| bool shouldOutlineFromFunctionByDefault(MachineFunction &MF) const override; |
| /// Returns true if the instruction has a shift by immediate that can be |
| /// executed in one cycle less. |
| static bool isFalkorShiftExtFast(const MachineInstr &MI); |
| /// Return true if the instructions is a SEH instruciton used for unwinding |
| /// on Windows. |
| static bool isSEHInstruction(const MachineInstr &MI); |
| |
| #define GET_INSTRINFO_HELPER_DECLS |
| #include "AArch64GenInstrInfo.inc" |
| |
| protected: |
| /// If the specific machine instruction is a instruction that moves/copies |
| /// value from one register to another register return true along with |
| /// @Source machine operand and @Destination machine operand. |
| bool isCopyInstrImpl(const MachineInstr &MI, const MachineOperand *&Source, |
| const MachineOperand *&Destination) const override; |
| |
| private: |
| /// Sets the offsets on outlined instructions in \p MBB which use SP |
| /// so that they will be valid post-outlining. |
| /// |
| /// \param MBB A \p MachineBasicBlock in an outlined function. |
| void fixupPostOutline(MachineBasicBlock &MBB) const; |
| |
| void instantiateCondBranch(MachineBasicBlock &MBB, const DebugLoc &DL, |
| MachineBasicBlock *TBB, |
| ArrayRef<MachineOperand> Cond) const; |
| bool substituteCmpToZero(MachineInstr &CmpInstr, unsigned SrcReg, |
| const MachineRegisterInfo *MRI) const; |
| |
| /// Returns an unused general-purpose register which can be used for |
| /// constructing an outlined call if one exists. Returns 0 otherwise. |
| unsigned findRegisterToSaveLRTo(const outliner::Candidate &C) const; |
| }; |
| |
| /// emitFrameOffset - Emit instructions as needed to set DestReg to SrcReg |
| /// plus Offset. This is intended to be used from within the prolog/epilog |
| /// insertion (PEI) pass, where a virtual scratch register may be allocated |
| /// if necessary, to be replaced by the scavenger at the end of PEI. |
| void emitFrameOffset(MachineBasicBlock &MBB, MachineBasicBlock::iterator MBBI, |
| const DebugLoc &DL, unsigned DestReg, unsigned SrcReg, |
| StackOffset Offset, const TargetInstrInfo *TII, |
| MachineInstr::MIFlag = MachineInstr::NoFlags, |
| bool SetNZCV = false, bool NeedsWinCFI = false, |
| bool *HasWinCFI = nullptr); |
| |
| /// rewriteAArch64FrameIndex - Rewrite MI to access 'Offset' bytes from the |
| /// FP. Return false if the offset could not be handled directly in MI, and |
| /// return the left-over portion by reference. |
| bool rewriteAArch64FrameIndex(MachineInstr &MI, unsigned FrameRegIdx, |
| unsigned FrameReg, StackOffset &Offset, |
| const AArch64InstrInfo *TII); |
| |
| /// Use to report the frame offset status in isAArch64FrameOffsetLegal. |
| enum AArch64FrameOffsetStatus { |
| AArch64FrameOffsetCannotUpdate = 0x0, ///< Offset cannot apply. |
| AArch64FrameOffsetIsLegal = 0x1, ///< Offset is legal. |
| AArch64FrameOffsetCanUpdate = 0x2 ///< Offset can apply, at least partly. |
| }; |
| |
| /// Check if the @p Offset is a valid frame offset for @p MI. |
| /// The returned value reports the validity of the frame offset for @p MI. |
| /// It uses the values defined by AArch64FrameOffsetStatus for that. |
| /// If result == AArch64FrameOffsetCannotUpdate, @p MI cannot be updated to |
| /// use an offset.eq |
| /// If result & AArch64FrameOffsetIsLegal, @p Offset can completely be |
| /// rewritten in @p MI. |
| /// If result & AArch64FrameOffsetCanUpdate, @p Offset contains the |
| /// amount that is off the limit of the legal offset. |
| /// If set, @p OutUseUnscaledOp will contain the whether @p MI should be |
| /// turned into an unscaled operator, which opcode is in @p OutUnscaledOp. |
| /// If set, @p EmittableOffset contains the amount that can be set in @p MI |
| /// (possibly with @p OutUnscaledOp if OutUseUnscaledOp is true) and that |
| /// is a legal offset. |
| int isAArch64FrameOffsetLegal(const MachineInstr &MI, StackOffset &Offset, |
| bool *OutUseUnscaledOp = nullptr, |
| unsigned *OutUnscaledOp = nullptr, |
| int64_t *EmittableOffset = nullptr); |
| |
| static inline bool isUncondBranchOpcode(int Opc) { return Opc == AArch64::B; } |
| |
| static inline bool isCondBranchOpcode(int Opc) { |
| switch (Opc) { |
| case AArch64::Bcc: |
| case AArch64::CBZW: |
| case AArch64::CBZX: |
| case AArch64::CBNZW: |
| case AArch64::CBNZX: |
| case AArch64::TBZW: |
| case AArch64::TBZX: |
| case AArch64::TBNZW: |
| case AArch64::TBNZX: |
| return true; |
| default: |
| return false; |
| } |
| } |
| |
| static inline bool isIndirectBranchOpcode(int Opc) { |
| return Opc == AArch64::BR; |
| } |
| |
| // struct TSFlags { |
| #define TSFLAG_ELEMENT_SIZE_TYPE(X) (X) // 3-bits |
| #define TSFLAG_DESTRUCTIVE_INST_TYPE(X) ((X) << 3) // 1-bit |
| // } |
| |
| namespace AArch64 { |
| |
| enum ElementSizeType { |
| ElementSizeMask = TSFLAG_ELEMENT_SIZE_TYPE(0x7), |
| ElementSizeNone = TSFLAG_ELEMENT_SIZE_TYPE(0x0), |
| ElementSizeB = TSFLAG_ELEMENT_SIZE_TYPE(0x1), |
| ElementSizeH = TSFLAG_ELEMENT_SIZE_TYPE(0x2), |
| ElementSizeS = TSFLAG_ELEMENT_SIZE_TYPE(0x3), |
| ElementSizeD = TSFLAG_ELEMENT_SIZE_TYPE(0x4), |
| }; |
| |
| enum DestructiveInstType { |
| DestructiveInstTypeMask = TSFLAG_DESTRUCTIVE_INST_TYPE(0x1), |
| NotDestructive = TSFLAG_DESTRUCTIVE_INST_TYPE(0x0), |
| Destructive = TSFLAG_DESTRUCTIVE_INST_TYPE(0x1), |
| }; |
| |
| #undef TSFLAG_ELEMENT_SIZE_TYPE |
| #undef TSFLAG_DESTRUCTIVE_INST_TYPE |
| } |
| |
| } // end namespace llvm |
| |
| #endif |