1 //===-- Thumb1FrameLowering.h - Thumb1-specific frame info stuff --*- C++ -*-=//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
12 //===----------------------------------------------------------------------===//
14 #ifndef LLVM_LIB_TARGET_ARM_THUMB1FRAMELOWERING_H
15 #define LLVM_LIB_TARGET_ARM_THUMB1FRAMELOWERING_H
17 #include "ARMFrameLowering.h"
18 #include "Thumb1InstrInfo.h"
19 #include "ThumbRegisterInfo.h"
20 #include "llvm/Target/TargetFrameLowering.h"
24 class Thumb1FrameLowering : public ARMFrameLowering {
26 explicit Thumb1FrameLowering(const ARMSubtarget &sti);
28 /// emitProlog/emitEpilog - These methods insert prolog and epilog code into
30 void emitPrologue(MachineFunction &MF, MachineBasicBlock &MBB) const override;
31 void emitEpilogue(MachineFunction &MF, MachineBasicBlock &MBB) const override;
33 bool spillCalleeSavedRegisters(MachineBasicBlock &MBB,
34 MachineBasicBlock::iterator MI,
35 const std::vector<CalleeSavedInfo> &CSI,
36 const TargetRegisterInfo *TRI) const override;
37 bool restoreCalleeSavedRegisters(MachineBasicBlock &MBB,
38 MachineBasicBlock::iterator MI,
39 const std::vector<CalleeSavedInfo> &CSI,
40 const TargetRegisterInfo *TRI) const override;
42 bool hasReservedCallFrame(const MachineFunction &MF) const override;
45 eliminateCallFramePseudoInstr(MachineFunction &MF,
46 MachineBasicBlock &MBB,
47 MachineBasicBlock::iterator MI) const override;
49 /// Check whether or not the given \p MBB can be used as a epilogue
51 /// The epilogue will be inserted before the first terminator of that block.
52 /// This method is used by the shrink-wrapping pass to decide if
53 /// \p MBB will be correctly handled by the target.
54 bool canUseAsEpilogue(const MachineBasicBlock &MBB) const override;
57 /// Check if the frame lowering of \p MF needs a special fixup
58 /// code sequence for the epilogue.
59 /// Unlike T2 and ARM mode, the T1 pop instruction cannot restore
60 /// to LR, and we can't pop the value directly to the PC when
61 /// we need to update the SP after popping the value. So instead
66 /// If this would clobber a return value, then generate this sequence instead:
73 bool needPopSpecialFixUp(const MachineFunction &MF) const;
75 /// Emit the special fixup code sequence for the epilogue.
76 /// \see needPopSpecialFixUp for more details.
77 /// \p DoIt, tells this method whether or not to actually insert
78 /// the code sequence in \p MBB. I.e., when \p DoIt is false,
79 /// \p MBB is left untouched.
80 /// \returns For \p DoIt == true: True when the emission succeeded
81 /// false otherwise. For \p DoIt == false: True when the emission
82 /// would have been possible, false otherwise.
83 bool emitPopSpecialFixUp(MachineBasicBlock &MBB, bool DoIt) const;
86 } // End llvm namespace