AArch64FrameLowering.h revision 355940 
1//==-- AArch64FrameLowering.h - TargetFrameLowering for AArch64 --*- C++ -*-==//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9//
10//
11//===----------------------------------------------------------------------===//
12
13#ifndef LLVM_LIB_TARGET_AARCH64_AARCH64FRAMELOWERING_H
14#define LLVM_LIB_TARGET_AARCH64_AARCH64FRAMELOWERING_H
15
16#include "llvm/CodeGen/TargetFrameLowering.h"
17
18namespace llvm {
19
20class AArch64FrameLowering : public TargetFrameLowering {
21public:
22  explicit AArch64FrameLowering()
23      : TargetFrameLowering(StackGrowsDown, 16, 0, 16,
24                            true /*StackRealignable*/) {}
25
26  void emitCalleeSavedFrameMoves(MachineBasicBlock &MBB,
27                                 MachineBasicBlock::iterator MBBI) const;
28
29  MachineBasicBlock::iterator
30  eliminateCallFramePseudoInstr(MachineFunction &MF, MachineBasicBlock &MBB,
31                                MachineBasicBlock::iterator I) const override;
32
33  /// emitProlog/emitEpilog - These methods insert prolog and epilog code into
34  /// the function.
35  void emitPrologue(MachineFunction &MF, MachineBasicBlock &MBB) const override;
36  void emitEpilogue(MachineFunction &MF, MachineBasicBlock &MBB) const override;
37
38  bool canUseAsPrologue(const MachineBasicBlock &MBB) const override;
39
40  int getFrameIndexReference(const MachineFunction &MF, int FI,
41                             unsigned &FrameReg) const override;
42  int resolveFrameIndexReference(const MachineFunction &MF, int FI,
43                                 unsigned &FrameReg, bool PreferFP,
44                                 bool ForSimm) const;
45  int resolveFrameOffsetReference(const MachineFunction &MF, int ObjectOffset,
46                                  bool isFixed, unsigned &FrameReg,
47                                  bool PreferFP, bool ForSimm) const;
48  bool spillCalleeSavedRegisters(MachineBasicBlock &MBB,
49                                 MachineBasicBlock::iterator MI,
50                                 const std::vector<CalleeSavedInfo> &CSI,
51                                 const TargetRegisterInfo *TRI) const override;
52
53  bool restoreCalleeSavedRegisters(MachineBasicBlock &MBB,
54                                  MachineBasicBlock::iterator MI,
55                                  std::vector<CalleeSavedInfo> &CSI,
56                                  const TargetRegisterInfo *TRI) const override;
57
58  /// Can this function use the red zone for local allocations.
59  bool canUseRedZone(const MachineFunction &MF) const;
60
61  bool hasFP(const MachineFunction &MF) const override;
62  bool hasReservedCallFrame(const MachineFunction &MF) const override;
63
64  void determineCalleeSaves(MachineFunction &MF, BitVector &SavedRegs,
65                            RegScavenger *RS) const override;
66
67  /// Returns true if the target will correctly handle shrink wrapping.
68  bool enableShrinkWrapping(const MachineFunction &MF) const override {
69    return true;
70  }
71
72  bool enableStackSlotScavenging(const MachineFunction &MF) const override;
73
74  void processFunctionBeforeFrameFinalized(MachineFunction &MF,
75                                             RegScavenger *RS) const override;
76
77  unsigned getWinEHParentFrameOffset(const MachineFunction &MF) const override;
78
79  unsigned getWinEHFuncletFrameSize(const MachineFunction &MF) const;
80
81  int getFrameIndexReferencePreferSP(const MachineFunction &MF, int FI,
82                                     unsigned &FrameReg,
83                                     bool IgnoreSPUpdates) const override;
84  int getNonLocalFrameIndexReference(const MachineFunction &MF,
85                               int FI) const override;
86  int getSEHFrameIndexOffset(const MachineFunction &MF, int FI) const;
87
88private:
89  bool shouldCombineCSRLocalStackBump(MachineFunction &MF,
90                                      unsigned StackBumpBytes) const;
91};
92
93} // End llvm namespace
94
95#endif
96