llvm/lib/Target/PowerPC/PPCInstrInfo.h - toolchain/llvm-project - Gitiles

 //===-- PPCInstrInfo.h - PowerPC Instruction Information --------*- C++ -*-===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // This file contains the PowerPC implementation of the TargetInstrInfo class.
 //
 //===----------------------------------------------------------------------===//

 #ifndef LLVM_LIB_TARGET_POWERPC_PPCINSTRINFO_H
 #define LLVM_LIB_TARGET_POWERPC_PPCINSTRINFO_H

 #include "PPC.h"
 #include "PPCRegisterInfo.h"
 #include "llvm/CodeGen/TargetInstrInfo.h"

 #define GET_INSTRINFO_HEADER
 #include "PPCGenInstrInfo.inc"

 namespace llvm {

 /// PPCII - This namespace holds all of the PowerPC target-specific
 /// per-instruction flags.  These must match the corresponding definitions in
 /// PPC.td and PPCInstrFormats.td.
 namespace PPCII {
 enum {
   // PPC970 Instruction Flags.  These flags describe the characteristics of the
   // PowerPC 970 (aka G5) dispatch groups and how they are formed out of
   // raw machine instructions.

   /// PPC970_First - This instruction starts a new dispatch group, so it will
   /// always be the first one in the group.
   PPC970_First = 0x1,

   /// PPC970_Single - This instruction starts a new dispatch group and
   /// terminates it, so it will be the sole instruction in the group.
   PPC970_Single = 0x2,

   /// PPC970_Cracked - This instruction is cracked into two pieces, requiring
   /// two dispatch pipes to be available to issue.
   PPC970_Cracked = 0x4,

   /// PPC970_Mask/Shift - This is a bitmask that selects the pipeline type that
   /// an instruction is issued to.
   PPC970_Shift = 3,
   PPC970_Mask = 0x07 << PPC970_Shift
 };
 enum PPC970_Unit {
   /// These are the various PPC970 execution unit pipelines.  Each instruction
   /// is one of these.
   PPC970_Pseudo = 0 << PPC970_Shift,   // Pseudo instruction
   PPC970_FXU    = 1 << PPC970_Shift,   // Fixed Point (aka Integer/ALU) Unit
   PPC970_LSU    = 2 << PPC970_Shift,   // Load Store Unit
   PPC970_FPU    = 3 << PPC970_Shift,   // Floating Point Unit
   PPC970_CRU    = 4 << PPC970_Shift,   // Control Register Unit
   PPC970_VALU   = 5 << PPC970_Shift,   // Vector ALU
   PPC970_VPERM  = 6 << PPC970_Shift,   // Vector Permute Unit
   PPC970_BRU    = 7 << PPC970_Shift    // Branch Unit
 };

 enum {
   /// Shift count to bypass PPC970 flags
   NewDef_Shift = 6,

   /// The VSX instruction that uses VSX register (vs0-vs63), instead of VMX
   /// register (v0-v31).
   UseVSXReg = 0x1 << NewDef_Shift
 };
 } // end namespace PPCII

 // Instructions that have an immediate form might be convertible to that
 // form if the correct input is a result of a load immediate. In order to
 // know whether the transformation is special, we might need to know some
 // of the details of the two forms.
 struct ImmInstrInfo {
   // Is the immediate field in the immediate form signed or unsigned?
   uint64_t SignedImm : 1;
   // Does the immediate need to be a multiple of some value?
   uint64_t ImmMustBeMultipleOf : 5;
   // Is R0/X0 treated specially by the original r+r instruction?
   // If so, in which operand?
   uint64_t ZeroIsSpecialOrig : 3;
   // Is R0/X0 treated specially by the new r+i instruction?
   // If so, in which operand?
   uint64_t ZeroIsSpecialNew : 3;
   // Is the operation commutative?
   uint64_t IsCommutative : 1;
   // The operand number to check for load immediate.
   uint64_t ConstantOpNo : 3;
   // The operand number for the immediate.
   uint64_t ImmOpNo : 3;
   // The opcode of the new instruction.
   uint64_t ImmOpcode : 16;
   // The size of the immediate.
   uint64_t ImmWidth : 5;
   // The immediate should be truncated to N bits.
   uint64_t TruncateImmTo : 5;
 };

 // Information required to convert an instruction to just a materialized
 // immediate.
 struct LoadImmediateInfo {
   unsigned Imm : 16;
   unsigned Is64Bit : 1;
   unsigned SetCR : 1;
 };

 class PPCSubtarget;
 class PPCInstrInfo : public PPCGenInstrInfo {
   PPCSubtarget &Subtarget;
   const PPCRegisterInfo RI;

   bool StoreRegToStackSlot(MachineFunction &MF,
                            unsigned SrcReg, bool isKill, int FrameIdx,
                            const TargetRegisterClass *RC,
                            SmallVectorImpl<MachineInstr*> &NewMIs,
                            bool &NonRI, bool &SpillsVRS) const;
   bool LoadRegFromStackSlot(MachineFunction &MF, const DebugLoc &DL,
                             unsigned DestReg, int FrameIdx,
                             const TargetRegisterClass *RC,
                             SmallVectorImpl<MachineInstr *> &NewMIs,
                             bool &NonRI, bool &SpillsVRS) const;
   bool transformToImmForm(MachineInstr &MI, const ImmInstrInfo &III,
                           unsigned ConstantOpNo, int64_t Imm) const;
   MachineInstr *getConstantDefMI(MachineInstr &MI, unsigned &ConstOp,
                                  bool &SeenIntermediateUse) const;
   virtual void anchor();

 protected:
   /// Commutes the operands in the given instruction.
   /// The commutable operands are specified by their indices OpIdx1 and OpIdx2.
   ///
   /// Do not call this method for a non-commutable instruction or for
   /// non-commutable pair of operand indices OpIdx1 and OpIdx2.
   /// Even though the instruction is commutable, the method may still
   /// fail to commute the operands, null pointer is returned in such cases.
   ///
   /// For example, we can commute rlwimi instructions, but only if the
   /// rotate amt is zero.  We also have to munge the immediates a bit.
   MachineInstr *commuteInstructionImpl(MachineInstr &MI, bool NewMI,
                                        unsigned OpIdx1,
                                        unsigned OpIdx2) const override;

 public:
   explicit PPCInstrInfo(PPCSubtarget &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 PPCRegisterInfo &getRegisterInfo() const { return RI; }

   ScheduleHazardRecognizer *
   CreateTargetHazardRecognizer(const TargetSubtargetInfo *STI,
                                const ScheduleDAG *DAG) const override;
   ScheduleHazardRecognizer *
   CreateTargetPostRAHazardRecognizer(const InstrItineraryData *II,
                                      const ScheduleDAG *DAG) const override;

   unsigned getInstrLatency(const InstrItineraryData *ItinData,
                            const MachineInstr &MI,
                            unsigned *PredCost = nullptr) const override;

   int getOperandLatency(const InstrItineraryData *ItinData,
                         const MachineInstr &DefMI, unsigned DefIdx,
                         const MachineInstr &UseMI,
                         unsigned UseIdx) const override;
   int getOperandLatency(const InstrItineraryData *ItinData,
                         SDNode *DefNode, unsigned DefIdx,
                         SDNode *UseNode, unsigned UseIdx) const override {
     return PPCGenInstrInfo::getOperandLatency(ItinData, DefNode, DefIdx,
                                               UseNode, UseIdx);
   }

   bool hasLowDefLatency(const TargetSchedModel &SchedModel,
                         const MachineInstr &DefMI,
                         unsigned DefIdx) const override {
     // Machine LICM should hoist all instructions in low-register-pressure
     // situations; none are sufficiently free to justify leaving in a loop
     // body.
     return false;
   }

   bool useMachineCombiner() const override {
     return true;
   }

   /// Return true when there is potentially a faster code sequence
   /// for an instruction chain ending in <Root>. All potential patterns are
   /// output in the <Pattern> array.
   bool getMachineCombinerPatterns(
       MachineInstr &Root,
       SmallVectorImpl<MachineCombinerPattern> &P) const override;

   bool isAssociativeAndCommutative(const MachineInstr &Inst) const override;

   bool isCoalescableExtInstr(const MachineInstr &MI,
                              unsigned &SrcReg, unsigned &DstReg,
                              unsigned &SubIdx) const override;
   unsigned isLoadFromStackSlot(const MachineInstr &MI,
                                int &FrameIndex) const override;
   bool isReallyTriviallyReMaterializable(const MachineInstr &MI,
                                          AliasAnalysis *AA) const override;
   unsigned isStoreToStackSlot(const MachineInstr &MI,
                               int &FrameIndex) const override;

   bool findCommutedOpIndices(MachineInstr &MI, unsigned &SrcOpIdx1,
                              unsigned &SrcOpIdx2) const override;

   void insertNoop(MachineBasicBlock &MBB,
                   MachineBasicBlock::iterator MI) const override;


   // Branch analysis.
   bool analyzeBranch(MachineBasicBlock &MBB, MachineBasicBlock *&TBB,
                      MachineBasicBlock *&FBB,
                      SmallVectorImpl<MachineOperand> &Cond,
                      bool AllowModify) 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;

   // Select analysis.
   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 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;

   bool
   reverseBranchCondition(SmallVectorImpl<MachineOperand> &Cond) const override;

   bool FoldImmediate(MachineInstr &UseMI, MachineInstr &DefMI, unsigned Reg,
                      MachineRegisterInfo *MRI) const override;

   // If conversion by predication (only supported by some branch instructions).
   // All of the profitability checks always return true; it is always
   // profitable to use the predicated branches.
   bool isProfitableToIfCvt(MachineBasicBlock &MBB,
                           unsigned NumCycles, unsigned ExtraPredCycles,
                           BranchProbability Probability) const override {
     return true;
   }

   bool isProfitableToIfCvt(MachineBasicBlock &TMBB,
                            unsigned NumT, unsigned ExtraT,
                            MachineBasicBlock &FMBB,
                            unsigned NumF, unsigned ExtraF,
                            BranchProbability Probability) const override;

   bool isProfitableToDupForIfCvt(MachineBasicBlock &MBB, unsigned NumCycles,
                                  BranchProbability Probability) const override {
     return true;
   }

   bool isProfitableToUnpredicate(MachineBasicBlock &TMBB,
                                  MachineBasicBlock &FMBB) const override {
     return false;
   }

   // Predication support.
   bool isPredicated(const MachineInstr &MI) const override;

   bool isUnpredicatedTerminator(const MachineInstr &MI) const override;

   bool PredicateInstruction(MachineInstr &MI,
                             ArrayRef<MachineOperand> Pred) const override;

   bool SubsumesPredicate(ArrayRef<MachineOperand> Pred1,
                          ArrayRef<MachineOperand> Pred2) const override;

   bool DefinesPredicate(MachineInstr &MI,
                         std::vector<MachineOperand> &Pred) const override;

   bool isPredicable(const MachineInstr &MI) const override;

   // Comparison optimization.

   bool analyzeCompare(const MachineInstr &MI, unsigned &SrcReg,
                       unsigned &SrcReg2, int &Mask, int &Value) const override;

   bool optimizeCompareInstr(MachineInstr &CmpInstr, unsigned SrcReg,
                             unsigned SrcReg2, int Mask, int Value,
                             const MachineRegisterInfo *MRI) const override;

   /// GetInstSize - Return the number of bytes of code the specified
   /// instruction may be.  This returns the maximum number of bytes.
   ///
   unsigned getInstSizeInBytes(const MachineInstr &MI) const override;

   void getNoop(MCInst &NopInst) 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;

   // Expand VSX Memory Pseudo instruction to either a VSX or a FP instruction.
   bool expandVSXMemPseudo(MachineInstr &MI) const;

   // Lower pseudo instructions after register allocation.
   bool expandPostRAPseudo(MachineInstr &MI) const override;

   static bool isVFRegister(unsigned Reg) {
     return Reg >= PPC::VF0 && Reg <= PPC::VF31;
   }
   static bool isVRRegister(unsigned Reg) {
     return Reg >= PPC::V0 && Reg <= PPC::V31;
   }
   const TargetRegisterClass *updatedRC(const TargetRegisterClass *RC) const;
   static int getRecordFormOpcode(unsigned Opcode);

   bool isTOCSaveMI(const MachineInstr &MI) const;

   bool isSignOrZeroExtended(const MachineInstr &MI, bool SignExt,
                             const unsigned PhiDepth) const;

   /// Return true if the output of the instruction is always a sign-extended,
   /// i.e. 0 to 31-th bits are same as 32-th bit.
   bool isSignExtended(const MachineInstr &MI, const unsigned depth = 0) const {
     return isSignOrZeroExtended(MI, true, depth);
   }

   /// Return true if the output of the instruction is always zero-extended,
   /// i.e. 0 to 31-th bits are all zeros
   bool isZeroExtended(const MachineInstr &MI, const unsigned depth = 0) const {
    return isSignOrZeroExtended(MI, false, depth);
   }

   bool convertToImmediateForm(MachineInstr &MI,
                               MachineInstr **KilledDef = nullptr) const;
   void replaceInstrWithLI(MachineInstr &MI, const LoadImmediateInfo &LII) const;

   // This is used to find the "true" source register for n
   // Machine instruction. Returns the original SrcReg unless it is the target
   // of a copy-like operation, in which case we chain backwards through all
   // such operations to the ultimate source register.  If a
   // physical register is encountered, we stop the search.
   static unsigned lookThruCopyLike(unsigned SrcReg,
                                    const MachineRegisterInfo *MRI);
   bool instrHasImmForm(const MachineInstr &MI, ImmInstrInfo &III) const;
 };

 }

 #endif
	//===-- PPCInstrInfo.h - PowerPC Instruction Information --------- C++ --===//
	//
	// The LLVM Compiler Infrastructure
	//
	// This file is distributed under the University of Illinois Open Source
	// License. See LICENSE.TXT for details.
	//
	//===----------------------------------------------------------------------===//
	//
	// This file contains the PowerPC implementation of the TargetInstrInfo class.
	//
	//===----------------------------------------------------------------------===//

	#ifndef LLVM_LIB_TARGET_POWERPC_PPCINSTRINFO_H
	#define LLVM_LIB_TARGET_POWERPC_PPCINSTRINFO_H

	#include "PPC.h"
	#include "PPCRegisterInfo.h"
	#include "llvm/CodeGen/TargetInstrInfo.h"

	#define GET_INSTRINFO_HEADER
	#include "PPCGenInstrInfo.inc"

	namespace llvm {

	/// PPCII - This namespace holds all of the PowerPC target-specific
	/// per-instruction flags. These must match the corresponding definitions in
	/// PPC.td and PPCInstrFormats.td.
	namespace PPCII {
	enum {
	// PPC970 Instruction Flags. These flags describe the characteristics of the
	// PowerPC 970 (aka G5) dispatch groups and how they are formed out of
	// raw machine instructions.

	/// PPC970_First - This instruction starts a new dispatch group, so it will
	/// always be the first one in the group.
	PPC970_First = 0x1,

	/// PPC970_Single - This instruction starts a new dispatch group and
	/// terminates it, so it will be the sole instruction in the group.
	PPC970_Single = 0x2,

	/// PPC970_Cracked - This instruction is cracked into two pieces, requiring
	/// two dispatch pipes to be available to issue.
	PPC970_Cracked = 0x4,

	/// PPC970_Mask/Shift - This is a bitmask that selects the pipeline type that
	/// an instruction is issued to.
	PPC970_Shift = 3,
	PPC970_Mask = 0x07 << PPC970_Shift
	};
	enum PPC970_Unit {
	/// These are the various PPC970 execution unit pipelines. Each instruction
	/// is one of these.
	PPC970_Pseudo = 0 << PPC970_Shift, // Pseudo instruction
	PPC970_FXU = 1 << PPC970_Shift, // Fixed Point (aka Integer/ALU) Unit
	PPC970_LSU = 2 << PPC970_Shift, // Load Store Unit
	PPC970_FPU = 3 << PPC970_Shift, // Floating Point Unit
	PPC970_CRU = 4 << PPC970_Shift, // Control Register Unit
	PPC970_VALU = 5 << PPC970_Shift, // Vector ALU
	PPC970_VPERM = 6 << PPC970_Shift, // Vector Permute Unit
	PPC970_BRU = 7 << PPC970_Shift // Branch Unit
	};

	enum {
	/// Shift count to bypass PPC970 flags
	NewDef_Shift = 6,

	/// The VSX instruction that uses VSX register (vs0-vs63), instead of VMX
	/// register (v0-v31).
	UseVSXReg = 0x1 << NewDef_Shift
	};
	} // end namespace PPCII

	// Instructions that have an immediate form might be convertible to that
	// form if the correct input is a result of a load immediate. In order to
	// know whether the transformation is special, we might need to know some
	// of the details of the two forms.
	struct ImmInstrInfo {
	// Is the immediate field in the immediate form signed or unsigned?
	uint64_t SignedImm : 1;
	// Does the immediate need to be a multiple of some value?
	uint64_t ImmMustBeMultipleOf : 5;
	// Is R0/X0 treated specially by the original r+r instruction?
	// If so, in which operand?
	uint64_t ZeroIsSpecialOrig : 3;
	// Is R0/X0 treated specially by the new r+i instruction?
	// If so, in which operand?
	uint64_t ZeroIsSpecialNew : 3;
	// Is the operation commutative?
	uint64_t IsCommutative : 1;
	// The operand number to check for load immediate.
	uint64_t ConstantOpNo : 3;
	// The operand number for the immediate.
	uint64_t ImmOpNo : 3;
	// The opcode of the new instruction.
	uint64_t ImmOpcode : 16;
	// The size of the immediate.
	uint64_t ImmWidth : 5;
	// The immediate should be truncated to N bits.
	uint64_t TruncateImmTo : 5;
	};

	// Information required to convert an instruction to just a materialized
	// immediate.
	struct LoadImmediateInfo {
	unsigned Imm : 16;
	unsigned Is64Bit : 1;
	unsigned SetCR : 1;
	};

	class PPCSubtarget;
	class PPCInstrInfo : public PPCGenInstrInfo {
	PPCSubtarget &Subtarget;
	const PPCRegisterInfo RI;

	bool StoreRegToStackSlot(MachineFunction &MF,
	unsigned SrcReg, bool isKill, int FrameIdx,
	const TargetRegisterClass *RC,
	SmallVectorImpl<MachineInstr*> &NewMIs,
	bool &NonRI, bool &SpillsVRS) const;
	bool LoadRegFromStackSlot(MachineFunction &MF, const DebugLoc &DL,
	unsigned DestReg, int FrameIdx,
	const TargetRegisterClass *RC,
	SmallVectorImpl<MachineInstr *> &NewMIs,
	bool &NonRI, bool &SpillsVRS) const;
	bool transformToImmForm(MachineInstr &MI, const ImmInstrInfo &III,
	unsigned ConstantOpNo, int64_t Imm) const;
	MachineInstr *getConstantDefMI(MachineInstr &MI, unsigned &ConstOp,
	bool &SeenIntermediateUse) const;
	virtual void anchor();

	protected:
	/// Commutes the operands in the given instruction.
	/// The commutable operands are specified by their indices OpIdx1 and OpIdx2.
	///
	/// Do not call this method for a non-commutable instruction or for
	/// non-commutable pair of operand indices OpIdx1 and OpIdx2.
	/// Even though the instruction is commutable, the method may still
	/// fail to commute the operands, null pointer is returned in such cases.
	///
	/// For example, we can commute rlwimi instructions, but only if the
	/// rotate amt is zero. We also have to munge the immediates a bit.
	MachineInstr *commuteInstructionImpl(MachineInstr &MI, bool NewMI,
	unsigned OpIdx1,
	unsigned OpIdx2) const override;

	public:
	explicit PPCInstrInfo(PPCSubtarget &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 PPCRegisterInfo &getRegisterInfo() const { return RI; }

	ScheduleHazardRecognizer *
	CreateTargetHazardRecognizer(const TargetSubtargetInfo *STI,
	const ScheduleDAG *DAG) const override;
	ScheduleHazardRecognizer *
	CreateTargetPostRAHazardRecognizer(const InstrItineraryData *II,
	const ScheduleDAG *DAG) const override;

	unsigned getInstrLatency(const InstrItineraryData *ItinData,
	const MachineInstr &MI,
	unsigned *PredCost = nullptr) const override;

	int getOperandLatency(const InstrItineraryData *ItinData,
	const MachineInstr &DefMI, unsigned DefIdx,
	const MachineInstr &UseMI,
	unsigned UseIdx) const override;
	int getOperandLatency(const InstrItineraryData *ItinData,
	SDNode *DefNode, unsigned DefIdx,
	SDNode *UseNode, unsigned UseIdx) const override {
	return PPCGenInstrInfo::getOperandLatency(ItinData, DefNode, DefIdx,
	UseNode, UseIdx);
	}

	bool hasLowDefLatency(const TargetSchedModel &SchedModel,
	const MachineInstr &DefMI,
	unsigned DefIdx) const override {
	// Machine LICM should hoist all instructions in low-register-pressure
	// situations; none are sufficiently free to justify leaving in a loop
	// body.
	return false;
	}

	bool useMachineCombiner() const override {
	return true;
	}

	/// Return true when there is potentially a faster code sequence
	/// for an instruction chain ending in <Root>. All potential patterns are
	/// output in the <Pattern> array.
	bool getMachineCombinerPatterns(
	MachineInstr &Root,
	SmallVectorImpl<MachineCombinerPattern> &P) const override;

	bool isAssociativeAndCommutative(const MachineInstr &Inst) const override;

	bool isCoalescableExtInstr(const MachineInstr &MI,
	unsigned &SrcReg, unsigned &DstReg,
	unsigned &SubIdx) const override;
	unsigned isLoadFromStackSlot(const MachineInstr &MI,
	int &FrameIndex) const override;
	bool isReallyTriviallyReMaterializable(const MachineInstr &MI,
	AliasAnalysis *AA) const override;
	unsigned isStoreToStackSlot(const MachineInstr &MI,
	int &FrameIndex) const override;

	bool findCommutedOpIndices(MachineInstr &MI, unsigned &SrcOpIdx1,
	unsigned &SrcOpIdx2) const override;

	void insertNoop(MachineBasicBlock &MBB,
	MachineBasicBlock::iterator MI) const override;


	// Branch analysis.
	bool analyzeBranch(MachineBasicBlock &MBB, MachineBasicBlock *&TBB,
	MachineBasicBlock *&FBB,
	SmallVectorImpl<MachineOperand> &Cond,
	bool AllowModify) 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;

	// Select analysis.
	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 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;

	bool
	reverseBranchCondition(SmallVectorImpl<MachineOperand> &Cond) const override;

	bool FoldImmediate(MachineInstr &UseMI, MachineInstr &DefMI, unsigned Reg,
	MachineRegisterInfo *MRI) const override;

	// If conversion by predication (only supported by some branch instructions).
	// All of the profitability checks always return true; it is always
	// profitable to use the predicated branches.
	bool isProfitableToIfCvt(MachineBasicBlock &MBB,
	unsigned NumCycles, unsigned ExtraPredCycles,
	BranchProbability Probability) const override {
	return true;
	}

	bool isProfitableToIfCvt(MachineBasicBlock &TMBB,
	unsigned NumT, unsigned ExtraT,
	MachineBasicBlock &FMBB,
	unsigned NumF, unsigned ExtraF,
	BranchProbability Probability) const override;

	bool isProfitableToDupForIfCvt(MachineBasicBlock &MBB, unsigned NumCycles,
	BranchProbability Probability) const override {
	return true;
	}

	bool isProfitableToUnpredicate(MachineBasicBlock &TMBB,
	MachineBasicBlock &FMBB) const override {
	return false;
	}

	// Predication support.
	bool isPredicated(const MachineInstr &MI) const override;

	bool isUnpredicatedTerminator(const MachineInstr &MI) const override;

	bool PredicateInstruction(MachineInstr &MI,
	ArrayRef<MachineOperand> Pred) const override;

	bool SubsumesPredicate(ArrayRef<MachineOperand> Pred1,
	ArrayRef<MachineOperand> Pred2) const override;

	bool DefinesPredicate(MachineInstr &MI,
	std::vector<MachineOperand> &Pred) const override;

	bool isPredicable(const MachineInstr &MI) const override;

	// Comparison optimization.

	bool analyzeCompare(const MachineInstr &MI, unsigned &SrcReg,
	unsigned &SrcReg2, int &Mask, int &Value) const override;

	bool optimizeCompareInstr(MachineInstr &CmpInstr, unsigned SrcReg,
	unsigned SrcReg2, int Mask, int Value,
	const MachineRegisterInfo *MRI) const override;

	/// GetInstSize - Return the number of bytes of code the specified
	/// instruction may be. This returns the maximum number of bytes.
	///
	unsigned getInstSizeInBytes(const MachineInstr &MI) const override;

	void getNoop(MCInst &NopInst) 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;

	// Expand VSX Memory Pseudo instruction to either a VSX or a FP instruction.
	bool expandVSXMemPseudo(MachineInstr &MI) const;

	// Lower pseudo instructions after register allocation.
	bool expandPostRAPseudo(MachineInstr &MI) const override;

	static bool isVFRegister(unsigned Reg) {
	return Reg >= PPC::VF0 && Reg <= PPC::VF31;
	}
	static bool isVRRegister(unsigned Reg) {
	return Reg >= PPC::V0 && Reg <= PPC::V31;
	}
	const TargetRegisterClass updatedRC(const TargetRegisterClass RC) const;
	static int getRecordFormOpcode(unsigned Opcode);

	bool isTOCSaveMI(const MachineInstr &MI) const;

	bool isSignOrZeroExtended(const MachineInstr &MI, bool SignExt,
	const unsigned PhiDepth) const;

	/// Return true if the output of the instruction is always a sign-extended,
	/// i.e. 0 to 31-th bits are same as 32-th bit.
	bool isSignExtended(const MachineInstr &MI, const unsigned depth = 0) const {
	return isSignOrZeroExtended(MI, true, depth);
	}

	/// Return true if the output of the instruction is always zero-extended,
	/// i.e. 0 to 31-th bits are all zeros
	bool isZeroExtended(const MachineInstr &MI, const unsigned depth = 0) const {
	return isSignOrZeroExtended(MI, false, depth);
	}

	bool convertToImmediateForm(MachineInstr &MI,
	MachineInstr **KilledDef = nullptr) const;
	void replaceInstrWithLI(MachineInstr &MI, const LoadImmediateInfo &LII) const;

	// This is used to find the "true" source register for n
	// Machine instruction. Returns the original SrcReg unless it is the target
	// of a copy-like operation, in which case we chain backwards through all
	// such operations to the ultimate source register. If a
	// physical register is encountered, we stop the search.
	static unsigned lookThruCopyLike(unsigned SrcReg,
	const MachineRegisterInfo *MRI);
	bool instrHasImmForm(const MachineInstr &MI, ImmInstrInfo &III) const;
	};

	}

	#endif