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1//===- ARMTargetFrameLowering.h - Define frame lowering for ARM -*- 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-exception6//7//===----------------------------------------------------------------------===//8 9#ifndef LLVM_LIB_TARGET_ARM_ARMFRAMELOWERING_H10#define LLVM_LIB_TARGET_ARM_ARMFRAMELOWERING_H11 12#include "llvm/CodeGen/TargetFrameLowering.h"13#include "llvm/Support/TypeSize.h"14 15namespace llvm {16 17class ARMSubtarget;18class CalleeSavedInfo;19class MachineFunction;20 21class ARMFrameLowering : public TargetFrameLowering {22protected:23 const ARMSubtarget &STI;24 25public:26 explicit ARMFrameLowering(const ARMSubtarget &sti);27 28 /// emitProlog/emitEpilog - These methods insert prolog and epilog code into29 /// the function.30 void emitPrologue(MachineFunction &MF, MachineBasicBlock &MBB) const override;31 void emitEpilogue(MachineFunction &MF, MachineBasicBlock &MBB) const override;32 33 bool spillCalleeSavedRegisters(MachineBasicBlock &MBB,34 MachineBasicBlock::iterator MI,35 ArrayRef<CalleeSavedInfo> CSI,36 const TargetRegisterInfo *TRI) const override;37 38 bool39 restoreCalleeSavedRegisters(MachineBasicBlock &MBB,40 MachineBasicBlock::iterator MI,41 MutableArrayRef<CalleeSavedInfo> CSI,42 const TargetRegisterInfo *TRI) const override;43 44 bool keepFramePointer(const MachineFunction &MF) const;45 46 bool enableCalleeSaveSkip(const MachineFunction &MF) const override;47 48 bool isFPReserved(const MachineFunction &MF) const;49 bool requiresAAPCSFrameRecord(const MachineFunction &MF) const;50 bool hasReservedCallFrame(const MachineFunction &MF) const override;51 bool canSimplifyCallFramePseudos(const MachineFunction &MF) const override;52 StackOffset getFrameIndexReference(const MachineFunction &MF, int FI,53 Register &FrameReg) const override;54 int ResolveFrameIndexReference(const MachineFunction &MF, int FI,55 Register &FrameReg, int SPAdj) const;56 57 void getCalleeSaves(const MachineFunction &MF,58 BitVector &SavedRegs) const override;59 void determineCalleeSaves(MachineFunction &MF, BitVector &SavedRegs,60 RegScavenger *RS) const override;61 62 /// Update the IsRestored flag on LR if it is spilled, based on the return63 /// instructions.64 static void updateLRRestored(MachineFunction &MF);65 66 void processFunctionBeforeFrameFinalized(67 MachineFunction &MF, RegScavenger *RS = nullptr) const override;68 69 void adjustForSegmentedStacks(MachineFunction &MF,70 MachineBasicBlock &MBB) const override;71 72 /// Returns true if the target will correctly handle shrink wrapping.73 bool enableShrinkWrapping(const MachineFunction &MF) const override;74 75 bool isProfitableForNoCSROpt(const Function &F) const override {76 // The no-CSR optimisation is bad for code size on ARM, because we can save77 // many registers with a single PUSH/POP pair.78 return false;79 }80 81 bool82 assignCalleeSavedSpillSlots(MachineFunction &MF,83 const TargetRegisterInfo *TRI,84 std::vector<CalleeSavedInfo> &CSI) const override;85 86 const SpillSlot *87 getCalleeSavedSpillSlots(unsigned &NumEntries) const override;88 89protected:90 bool hasFPImpl(const MachineFunction &MF) const override;91 92private:93 void emitPushInst(MachineBasicBlock &MBB, MachineBasicBlock::iterator MI,94 ArrayRef<CalleeSavedInfo> CSI, unsigned StmOpc,95 unsigned StrOpc, bool NoGap,96 function_ref<bool(unsigned)> Func) const;97 void emitPopInst(MachineBasicBlock &MBB, MachineBasicBlock::iterator MI,98 MutableArrayRef<CalleeSavedInfo> CSI, unsigned LdmOpc,99 unsigned LdrOpc, bool isVarArg, bool NoGap,100 function_ref<bool(unsigned)> Func) const;101 102 void emitFPStatusSaves(MachineBasicBlock &MBB, MachineBasicBlock::iterator MI,103 ArrayRef<CalleeSavedInfo> CSI,104 unsigned PushOneOpc) const;105 106 void emitFPStatusRestores(MachineBasicBlock &MBB,107 MachineBasicBlock::iterator MI,108 MutableArrayRef<CalleeSavedInfo> CSI,109 unsigned LdrOpc) const;110 111 MachineBasicBlock::iterator112 eliminateCallFramePseudoInstr(MachineFunction &MF,113 MachineBasicBlock &MBB,114 MachineBasicBlock::iterator MI) const override;115};116 117} // end namespace llvm118 119#endif // LLVM_LIB_TARGET_ARM_ARMFRAMELOWERING_H120