summaryrefslogtreecommitdiff
path: root/lib/Target/AArch64/AArch64InstrInfo.h
blob: 90ce75f26d424e931ec14426b75c55e58de210f8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
//===- AArch64InstrInfo.h - AArch64 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 AArch64 implementation of the TargetInstrInfo class.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_TARGET_AArch64INSTRINFO_H
#define LLVM_TARGET_AArch64INSTRINFO_H

#include "AArch64.h"
#include "AArch64RegisterInfo.h"
#include "llvm/Target/TargetInstrInfo.h"

#define GET_INSTRINFO_HEADER
#include "AArch64GenInstrInfo.inc"

namespace llvm {

class AArch64Subtarget;
class AArch64TargetMachine;

class AArch64InstrInfo : public AArch64GenInstrInfo {
  // Reserve bits in the MachineMemOperand target hint flags, starting at 1.
  // They will be shifted into MOTargetHintStart when accessed.
  enum TargetMemOperandFlags {
    MOSuppressPair = 1
  };

  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; }

  const AArch64Subtarget &getSubTarget() const { return Subtarget; }

  unsigned GetInstSizeInBytes(const MachineInstr *MI) const;

  bool isCoalescableExtInstr(const MachineInstr &MI, unsigned &SrcReg,
                             unsigned &DstReg, unsigned &SubIdx) const override;

  unsigned isLoadFromStackSlot(const MachineInstr *MI,
                               int &FrameIndex) const override;
  unsigned isStoreToStackSlot(const MachineInstr *MI,
                              int &FrameIndex) const override;

  /// Returns true if there is a shiftable register and that the shift value
  /// is non-zero.
  bool hasShiftedReg(const MachineInstr *MI) const;

  /// Returns true if there is an extendable register and that the extending
  /// value is non-zero.
  bool hasExtendedReg(const MachineInstr *MI) const;

  /// \brief Does this instruction set its full destination register to zero?
  bool isGPRZero(const MachineInstr *MI) const;

  /// \brief Does this instruction rename a GPR without modifying bits?
  bool isGPRCopy(const MachineInstr *MI) const;

  /// \brief Does this instruction rename an FPR without modifying bits?
  bool isFPRCopy(const MachineInstr *MI) const;

  /// Return true if this is load/store scales or extends its register offset.
  /// This refers to scaling a dynamic index as opposed to scaled immediates.
  /// MI should be a memory op that allows scaled addressing.
  bool isScaledAddr(const MachineInstr *MI) const;

  /// Return true if pairing the given load or store is hinted to be
  /// unprofitable.
  bool isLdStPairSuppressed(const MachineInstr *MI) const;

  /// Hint that pairing the given load or store is unprofitable.
  void suppressLdStPair(MachineInstr *MI) const;

  bool getLdStBaseRegImmOfs(MachineInstr *LdSt, unsigned &BaseReg,
                            unsigned &Offset,
                            const TargetRegisterInfo *TRI) const override;

  bool enableClusterLoads() const override { return true; }

  bool shouldClusterLoads(MachineInstr *FirstLdSt, MachineInstr *SecondLdSt,
                          unsigned NumLoads) const override;

  bool shouldScheduleAdjacent(MachineInstr *First,
                              MachineInstr *Second) const override;

  MachineInstr *emitFrameIndexDebugValue(MachineFunction &MF, int FrameIx,
                                         uint64_t Offset, const MDNode *MDPtr,
                                         DebugLoc DL) const;
  void copyPhysRegTuple(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
                        DebugLoc DL, unsigned DestReg, unsigned SrcReg,
                        bool KillSrc, unsigned Opcode,
                        llvm::ArrayRef<unsigned> Indices) const;
  void copyPhysReg(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
                   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;

  MachineInstr *
  foldMemoryOperandImpl(MachineFunction &MF, MachineInstr *MI,
                        const SmallVectorImpl<unsigned> &Ops,
                        int FrameIndex) const override;

  bool AnalyzeBranch(MachineBasicBlock &MBB, MachineBasicBlock *&TBB,
                     MachineBasicBlock *&FBB,
                     SmallVectorImpl<MachineOperand> &Cond,
                     bool AllowModify = false) const override;
  unsigned RemoveBranch(MachineBasicBlock &MBB) const override;
  unsigned InsertBranch(MachineBasicBlock &MBB, MachineBasicBlock *TBB,
                        MachineBasicBlock *FBB,
                        const SmallVectorImpl<MachineOperand> &Cond,
                        DebugLoc DL) const override;
  bool
  ReverseBranchCondition(SmallVectorImpl<MachineOperand> &Cond) const override;
  bool canInsertSelect(const MachineBasicBlock &,
                       const SmallVectorImpl<MachineOperand> &Cond, unsigned,
                       unsigned, int &, int &, int &) const override;
  void insertSelect(MachineBasicBlock &MBB, MachineBasicBlock::iterator MI,
                    DebugLoc DL, unsigned DstReg,
                    const SmallVectorImpl<MachineOperand> &Cond,
                    unsigned TrueReg, unsigned FalseReg) const override;
  void getNoopForMachoTarget(MCInst &NopInst) 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;

private:
  void instantiateCondBranch(MachineBasicBlock &MBB, DebugLoc DL,
                             MachineBasicBlock *TBB,
                             const SmallVectorImpl<MachineOperand> &Cond) 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,
                     DebugLoc DL, unsigned DestReg, unsigned SrcReg, int Offset,
                     const AArch64InstrInfo *TII,
                     MachineInstr::MIFlag = MachineInstr::NoFlags,
                     bool SetNZCV = false);

/// 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, int &Offset,
                            const AArch64InstrInfo *TII);

/// \brief 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.
};

/// \brief 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
/// rewriten 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, int &Offset,
                            bool *OutUseUnscaledOp = nullptr,
                            unsigned *OutUnscaledOp = nullptr,
                            int *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; }

} // end namespace llvm

#endif