llvm-project/llvm/lib/Target/ARM/ARMBaseInstrInfo.h

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C++

//===-- ARMBaseInstrInfo.h - ARM Base 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 Base ARM implementation of the TargetInstrInfo class.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_LIB_TARGET_ARM_ARMBASEINSTRINFO_H
#define LLVM_LIB_TARGET_ARM_ARMBASEINSTRINFO_H
#include "MCTargetDesc/ARMBaseInfo.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/SmallSet.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/Support/CodeGen.h"
#include "llvm/Target/TargetInstrInfo.h"
#define GET_INSTRINFO_HEADER
#include "ARMGenInstrInfo.inc"
namespace llvm {
class ARMSubtarget;
class ARMBaseRegisterInfo;
class ARMBaseInstrInfo : public ARMGenInstrInfo {
const ARMSubtarget &Subtarget;
protected:
// Can be only subclassed.
explicit ARMBaseInstrInfo(const ARMSubtarget &STI);
void expandLoadStackGuardBase(MachineBasicBlock::iterator MI,
unsigned LoadImmOpc, unsigned LoadOpc) const;
/// Build the equivalent inputs of a REG_SEQUENCE for the given \p MI
/// and \p DefIdx.
/// \p [out] InputRegs of the equivalent REG_SEQUENCE. Each element of
/// the list is modeled as <Reg:SubReg, SubIdx>.
/// E.g., REG_SEQUENCE vreg1:sub1, sub0, vreg2, sub1 would produce
/// two elements:
/// - vreg1:sub1, sub0
/// - vreg2<:0>, sub1
///
/// \returns true if it is possible to build such an input sequence
/// with the pair \p MI, \p DefIdx. False otherwise.
///
/// \pre MI.isRegSequenceLike().
bool getRegSequenceLikeInputs(
const MachineInstr &MI, unsigned DefIdx,
SmallVectorImpl<RegSubRegPairAndIdx> &InputRegs) const override;
/// Build the equivalent inputs of a EXTRACT_SUBREG for the given \p MI
/// and \p DefIdx.
/// \p [out] InputReg of the equivalent EXTRACT_SUBREG.
/// E.g., EXTRACT_SUBREG vreg1:sub1, sub0, sub1 would produce:
/// - vreg1:sub1, sub0
///
/// \returns true if it is possible to build such an input sequence
/// with the pair \p MI, \p DefIdx. False otherwise.
///
/// \pre MI.isExtractSubregLike().
bool getExtractSubregLikeInputs(const MachineInstr &MI, unsigned DefIdx,
RegSubRegPairAndIdx &InputReg) const override;
/// Build the equivalent inputs of a INSERT_SUBREG for the given \p MI
/// and \p DefIdx.
/// \p [out] BaseReg and \p [out] InsertedReg contain
/// the equivalent inputs of INSERT_SUBREG.
/// E.g., INSERT_SUBREG vreg0:sub0, vreg1:sub1, sub3 would produce:
/// - BaseReg: vreg0:sub0
/// - InsertedReg: vreg1:sub1, sub3
///
/// \returns true if it is possible to build such an input sequence
/// with the pair \p MI, \p DefIdx. False otherwise.
///
/// \pre MI.isInsertSubregLike().
bool
getInsertSubregLikeInputs(const MachineInstr &MI, unsigned DefIdx,
RegSubRegPair &BaseReg,
RegSubRegPairAndIdx &InsertedReg) const override;
/// 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.
MachineInstr *commuteInstructionImpl(MachineInstr &MI, bool NewMI,
unsigned OpIdx1,
unsigned OpIdx2) const override;
public:
// Return whether the target has an explicit NOP encoding.
bool hasNOP() const;
virtual void getNoopForElfTarget(MCInst &NopInst) const {
getNoopForMachoTarget(NopInst);
}
// Return the non-pre/post incrementing version of 'Opc'. Return 0
// if there is not such an opcode.
virtual unsigned getUnindexedOpcode(unsigned Opc) const =0;
MachineInstr *convertToThreeAddress(MachineFunction::iterator &MFI,
MachineInstr &MI,
LiveVariables *LV) const override;
virtual const ARMBaseRegisterInfo &getRegisterInfo() const = 0;
const ARMSubtarget &getSubtarget() const { return Subtarget; }
ScheduleHazardRecognizer *
CreateTargetHazardRecognizer(const TargetSubtargetInfo *STI,
const ScheduleDAG *DAG) const override;
ScheduleHazardRecognizer *
CreateTargetPostRAHazardRecognizer(const InstrItineraryData *II,
const ScheduleDAG *DAG) const override;
// Branch analysis.
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;
// Predication support.
bool isPredicated(const MachineInstr &MI) const override;
ARMCC::CondCodes getPredicate(const MachineInstr &MI) const {
int PIdx = MI.findFirstPredOperandIdx();
return PIdx != -1 ? (ARMCC::CondCodes)MI.getOperand(PIdx).getImm()
: ARMCC::AL;
}
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(MachineInstr &MI) const override;
/// GetInstSize - Returns the size of the specified MachineInstr.
///
unsigned getInstSizeInBytes(const MachineInstr &MI) const override;
unsigned isLoadFromStackSlot(const MachineInstr &MI,
int &FrameIndex) const override;
unsigned isStoreToStackSlot(const MachineInstr &MI,
int &FrameIndex) const override;
unsigned isLoadFromStackSlotPostFE(const MachineInstr &MI,
int &FrameIndex) const override;
unsigned isStoreToStackSlotPostFE(const MachineInstr &MI,
int &FrameIndex) const override;
void copyToCPSR(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
unsigned SrcReg, bool KillSrc,
const ARMSubtarget &Subtarget) const;
void copyFromCPSR(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
unsigned DestReg, bool KillSrc,
const ARMSubtarget &Subtarget) 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;
bool expandPostRAPseudo(MachineInstr &MI) const override;
void reMaterialize(MachineBasicBlock &MBB, MachineBasicBlock::iterator MI,
unsigned DestReg, unsigned SubIdx,
const MachineInstr &Orig,
const TargetRegisterInfo &TRI) const override;
MachineInstr *duplicate(MachineInstr &Orig,
MachineFunction &MF) const override;
const MachineInstrBuilder &AddDReg(MachineInstrBuilder &MIB, unsigned Reg,
unsigned SubIdx, unsigned State,
const TargetRegisterInfo *TRI) const;
bool produceSameValue(const MachineInstr &MI0, const MachineInstr &MI1,
const MachineRegisterInfo *MRI) const override;
/// areLoadsFromSameBasePtr - This is used by the pre-regalloc scheduler to
/// determine if two loads are loading from the same base address. It should
/// only return true if the base pointers are the same and the only
/// differences between the two addresses is the offset. It also returns the
/// offsets by reference.
bool areLoadsFromSameBasePtr(SDNode *Load1, SDNode *Load2, int64_t &Offset1,
int64_t &Offset2) const override;
/// shouldScheduleLoadsNear - This is a used by the pre-regalloc scheduler to
/// determine (in conjunction with areLoadsFromSameBasePtr) if two loads
/// should be scheduled togther. On some targets if two loads are loading from
/// addresses in the same cache line, it's better if they are scheduled
/// together. This function takes two integers that represent the load offsets
/// from the common base address. It returns true if it decides it's desirable
/// to schedule the two loads together. "NumLoads" is the number of loads that
/// have already been scheduled after Load1.
bool shouldScheduleLoadsNear(SDNode *Load1, SDNode *Load2,
int64_t Offset1, int64_t Offset2,
unsigned NumLoads) const override;
bool isSchedulingBoundary(const MachineInstr &MI,
const MachineBasicBlock *MBB,
const MachineFunction &MF) const override;
bool isProfitableToIfCvt(MachineBasicBlock &MBB,
unsigned NumCycles, unsigned ExtraPredCycles,
BranchProbability Probability) const override;
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 NumCycles == 1;
}
bool isProfitableToUnpredicate(MachineBasicBlock &TMBB,
MachineBasicBlock &FMBB) const override;
/// analyzeCompare - For a comparison instruction, return the source registers
/// in SrcReg and SrcReg2 if having two register operands, 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 to set the zero flag so
/// that we can remove a "comparison with zero"; Remove a redundant CMP
/// instruction if the flags can be updated in the same way by an earlier
/// instruction such as SUB.
bool optimizeCompareInstr(MachineInstr &CmpInstr, unsigned SrcReg,
unsigned SrcReg2, int CmpMask, int CmpValue,
const MachineRegisterInfo *MRI) const override;
bool analyzeSelect(const MachineInstr &MI,
SmallVectorImpl<MachineOperand> &Cond, unsigned &TrueOp,
unsigned &FalseOp, bool &Optimizable) const override;
MachineInstr *optimizeSelect(MachineInstr &MI,
SmallPtrSetImpl<MachineInstr *> &SeenMIs,
bool) const override;
/// FoldImmediate - 'Reg' is known to be defined by a move immediate
/// instruction, try to fold the immediate into the use instruction.
bool FoldImmediate(MachineInstr &UseMI, MachineInstr &DefMI, unsigned Reg,
MachineRegisterInfo *MRI) const override;
unsigned getNumMicroOps(const InstrItineraryData *ItinData,
const MachineInstr &MI) 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;
/// VFP/NEON execution domains.
std::pair<uint16_t, uint16_t>
getExecutionDomain(const MachineInstr &MI) const override;
void setExecutionDomain(MachineInstr &MI, unsigned Domain) const override;
unsigned
getPartialRegUpdateClearance(const MachineInstr &, unsigned,
const TargetRegisterInfo *) const override;
void breakPartialRegDependency(MachineInstr &, unsigned,
const TargetRegisterInfo *TRI) const override;
/// Get the number of addresses by LDM or VLDM or zero for unknown.
unsigned getNumLDMAddresses(const MachineInstr &MI) const;
private:
unsigned getInstBundleLength(const MachineInstr &MI) const;
int getVLDMDefCycle(const InstrItineraryData *ItinData,
const MCInstrDesc &DefMCID,
unsigned DefClass,
unsigned DefIdx, unsigned DefAlign) const;
int getLDMDefCycle(const InstrItineraryData *ItinData,
const MCInstrDesc &DefMCID,
unsigned DefClass,
unsigned DefIdx, unsigned DefAlign) const;
int getVSTMUseCycle(const InstrItineraryData *ItinData,
const MCInstrDesc &UseMCID,
unsigned UseClass,
unsigned UseIdx, unsigned UseAlign) const;
int getSTMUseCycle(const InstrItineraryData *ItinData,
const MCInstrDesc &UseMCID,
unsigned UseClass,
unsigned UseIdx, unsigned UseAlign) const;
int getOperandLatency(const InstrItineraryData *ItinData,
const MCInstrDesc &DefMCID,
unsigned DefIdx, unsigned DefAlign,
const MCInstrDesc &UseMCID,
unsigned UseIdx, unsigned UseAlign) const;
int getOperandLatencyImpl(const InstrItineraryData *ItinData,
const MachineInstr &DefMI, unsigned DefIdx,
const MCInstrDesc &DefMCID, unsigned DefAdj,
const MachineOperand &DefMO, unsigned Reg,
const MachineInstr &UseMI, unsigned UseIdx,
const MCInstrDesc &UseMCID, unsigned UseAdj) const;
unsigned getPredicationCost(const MachineInstr &MI) const override;
unsigned getInstrLatency(const InstrItineraryData *ItinData,
const MachineInstr &MI,
unsigned *PredCost = nullptr) const override;
int getInstrLatency(const InstrItineraryData *ItinData,
SDNode *Node) const override;
bool hasHighOperandLatency(const TargetSchedModel &SchedModel,
const MachineRegisterInfo *MRI,
const MachineInstr &DefMI, unsigned DefIdx,
const MachineInstr &UseMI,
unsigned UseIdx) const override;
bool hasLowDefLatency(const TargetSchedModel &SchedModel,
const MachineInstr &DefMI,
unsigned DefIdx) const override;
/// verifyInstruction - Perform target specific instruction verification.
bool verifyInstruction(const MachineInstr &MI,
StringRef &ErrInfo) const override;
virtual void expandLoadStackGuard(MachineBasicBlock::iterator MI) const = 0;
void expandMEMCPY(MachineBasicBlock::iterator) const;
private:
/// Modeling special VFP / NEON fp MLA / MLS hazards.
/// MLxEntryMap - Map fp MLA / MLS to the corresponding entry in the internal
/// MLx table.
DenseMap<unsigned, unsigned> MLxEntryMap;
/// MLxHazardOpcodes - Set of add / sub and multiply opcodes that would cause
/// stalls when scheduled together with fp MLA / MLS opcodes.
SmallSet<unsigned, 16> MLxHazardOpcodes;
public:
/// isFpMLxInstruction - Return true if the specified opcode is a fp MLA / MLS
/// instruction.
bool isFpMLxInstruction(unsigned Opcode) const {
return MLxEntryMap.count(Opcode);
}
/// isFpMLxInstruction - This version also returns the multiply opcode and the
/// addition / subtraction opcode to expand to. Return true for 'HasLane' for
/// the MLX instructions with an extra lane operand.
bool isFpMLxInstruction(unsigned Opcode, unsigned &MulOpc,
unsigned &AddSubOpc, bool &NegAcc,
bool &HasLane) const;
/// canCauseFpMLxStall - Return true if an instruction of the specified opcode
/// will cause stalls when scheduled after (within 4-cycle window) a fp
/// MLA / MLS instruction.
bool canCauseFpMLxStall(unsigned Opcode) const {
return MLxHazardOpcodes.count(Opcode);
}
/// Returns true if the instruction has a shift by immediate that can be
/// executed in one cycle less.
bool isSwiftFastImmShift(const MachineInstr *MI) const;
};
static inline
const MachineInstrBuilder &AddDefaultPred(const MachineInstrBuilder &MIB) {
return MIB.addImm((int64_t)ARMCC::AL).addReg(0);
}
static inline
const MachineInstrBuilder &AddDefaultCC(const MachineInstrBuilder &MIB) {
return MIB.addReg(0);
}
static inline
const MachineInstrBuilder &AddDefaultT1CC(const MachineInstrBuilder &MIB,
bool isDead = false) {
return MIB.addReg(ARM::CPSR, getDefRegState(true) | getDeadRegState(isDead));
}
static inline
const MachineInstrBuilder &AddNoT1CC(const MachineInstrBuilder &MIB) {
return MIB.addReg(0);
}
static inline
bool isUncondBranchOpcode(int Opc) {
return Opc == ARM::B || Opc == ARM::tB || Opc == ARM::t2B;
}
static inline
bool isCondBranchOpcode(int Opc) {
return Opc == ARM::Bcc || Opc == ARM::tBcc || Opc == ARM::t2Bcc;
}
static inline
bool isJumpTableBranchOpcode(int Opc) {
return Opc == ARM::BR_JTr || Opc == ARM::BR_JTm || Opc == ARM::BR_JTadd ||
Opc == ARM::tBR_JTr || Opc == ARM::t2BR_JT;
}
static inline
bool isIndirectBranchOpcode(int Opc) {
return Opc == ARM::BX || Opc == ARM::MOVPCRX || Opc == ARM::tBRIND;
}
static inline bool isPopOpcode(int Opc) {
return Opc == ARM::tPOP_RET || Opc == ARM::LDMIA_RET ||
Opc == ARM::t2LDMIA_RET || Opc == ARM::tPOP || Opc == ARM::LDMIA_UPD ||
Opc == ARM::t2LDMIA_UPD || Opc == ARM::VLDMDIA_UPD;
}
static inline bool isPushOpcode(int Opc) {
return Opc == ARM::tPUSH || Opc == ARM::t2STMDB_UPD ||
Opc == ARM::STMDB_UPD || Opc == ARM::VSTMDDB_UPD;
}
/// getInstrPredicate - If instruction is predicated, returns its predicate
/// condition, otherwise returns AL. It also returns the condition code
/// register by reference.
ARMCC::CondCodes getInstrPredicate(const MachineInstr &MI, unsigned &PredReg);
unsigned getMatchingCondBranchOpcode(unsigned Opc);
/// Determine if MI can be folded into an ARM MOVCC instruction, and return the
/// opcode of the SSA instruction representing the conditional MI.
unsigned canFoldARMInstrIntoMOVCC(unsigned Reg,
MachineInstr *&MI,
const MachineRegisterInfo &MRI);
/// Map pseudo instructions that imply an 'S' bit onto real opcodes. Whether
/// the instruction is encoded with an 'S' bit is determined by the optional
/// CPSR def operand.
unsigned convertAddSubFlagsOpcode(unsigned OldOpc);
/// emitARMRegPlusImmediate / emitT2RegPlusImmediate - Emits a series of
/// instructions to materializea destreg = basereg + immediate in ARM / Thumb2
/// code.
void emitARMRegPlusImmediate(MachineBasicBlock &MBB,
MachineBasicBlock::iterator &MBBI,
const DebugLoc &dl, unsigned DestReg,
unsigned BaseReg, int NumBytes,
ARMCC::CondCodes Pred, unsigned PredReg,
const ARMBaseInstrInfo &TII, unsigned MIFlags = 0);
void emitT2RegPlusImmediate(MachineBasicBlock &MBB,
MachineBasicBlock::iterator &MBBI,
const DebugLoc &dl, unsigned DestReg,
unsigned BaseReg, int NumBytes,
ARMCC::CondCodes Pred, unsigned PredReg,
const ARMBaseInstrInfo &TII, unsigned MIFlags = 0);
void emitThumbRegPlusImmediate(MachineBasicBlock &MBB,
MachineBasicBlock::iterator &MBBI,
const DebugLoc &dl, unsigned DestReg,
unsigned BaseReg, int NumBytes,
const TargetInstrInfo &TII,
const ARMBaseRegisterInfo &MRI,
unsigned MIFlags = 0);
/// Tries to add registers to the reglist of a given base-updating
/// push/pop instruction to adjust the stack by an additional
/// NumBytes. This can save a few bytes per function in code-size, but
/// obviously generates more memory traffic. As such, it only takes
/// effect in functions being optimised for size.
bool tryFoldSPUpdateIntoPushPop(const ARMSubtarget &Subtarget,
MachineFunction &MF, MachineInstr *MI,
unsigned NumBytes);
/// rewriteARMFrameIndex / rewriteT2FrameIndex -
/// 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 rewriteARMFrameIndex(MachineInstr &MI, unsigned FrameRegIdx,
unsigned FrameReg, int &Offset,
const ARMBaseInstrInfo &TII);
bool rewriteT2FrameIndex(MachineInstr &MI, unsigned FrameRegIdx,
unsigned FrameReg, int &Offset,
const ARMBaseInstrInfo &TII);
} // End llvm namespace
#endif