diff options
Diffstat (limited to 'lib/Target/AArch64/AArch64FrameLowering.h')
-rw-r--r-- | lib/Target/AArch64/AArch64FrameLowering.h | 108 |
1 files changed, 108 insertions, 0 deletions
diff --git a/lib/Target/AArch64/AArch64FrameLowering.h b/lib/Target/AArch64/AArch64FrameLowering.h new file mode 100644 index 0000000..45ea0ec --- /dev/null +++ b/lib/Target/AArch64/AArch64FrameLowering.h @@ -0,0 +1,108 @@ +//==- AArch64FrameLowering.h - Define frame lowering for AArch64 -*- C++ -*--=// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This class implements the AArch64-specific parts of the TargetFrameLowering +// class. +// +//===----------------------------------------------------------------------===// + +#ifndef LLVM_AARCH64_FRAMEINFO_H +#define LLVM_AARCH64_FRAMEINFO_H + +#include "AArch64Subtarget.h" +#include "llvm/Target/TargetFrameLowering.h" + +namespace llvm { +class AArch64Subtarget; + +class AArch64FrameLowering : public TargetFrameLowering { +private: + // In order to unify the spilling and restoring of callee-saved registers into + // emitFrameMemOps, we need to be able to specify which instructions to use + // for the relevant memory operations on each register class. An array of the + // following struct is populated and passed in to achieve this. + struct LoadStoreMethod { + const TargetRegisterClass *RegClass; // E.g. GPR64RegClass + + // The preferred instruction. + unsigned PairOpcode; // E.g. LSPair64_STR + + // Sometimes only a single register can be handled at once. + unsigned SingleOpcode; // E.g. LS64_STR + }; +protected: + const AArch64Subtarget &STI; + +public: + explicit AArch64FrameLowering(const AArch64Subtarget &sti) + : TargetFrameLowering(TargetFrameLowering::StackGrowsDown, 16, 0, 16), + STI(sti) { + } + + /// emitProlog/emitEpilog - These methods insert prolog and epilog code into + /// the function. + virtual void emitPrologue(MachineFunction &MF) const; + virtual void emitEpilogue(MachineFunction &MF, MachineBasicBlock &MBB) const; + + /// Decides how much stack adjustment to perform in each phase of the prologue + /// and epilogue. + void splitSPAdjustments(uint64_t Total, uint64_t &Initial, + uint64_t &Residual) const; + + int64_t resolveFrameIndexReference(MachineFunction &MF, int FrameIndex, + unsigned &FrameReg, int SPAdj, + bool IsCalleeSaveOp) const; + + virtual void processFunctionBeforeCalleeSavedScan(MachineFunction &MF, + RegScavenger *RS) const; + + virtual bool spillCalleeSavedRegisters(MachineBasicBlock &MBB, + MachineBasicBlock::iterator MI, + const std::vector<CalleeSavedInfo> &CSI, + const TargetRegisterInfo *TRI) const; + virtual bool restoreCalleeSavedRegisters(MachineBasicBlock &MBB, + MachineBasicBlock::iterator MI, + const std::vector<CalleeSavedInfo> &CSI, + const TargetRegisterInfo *TRI) const; + + void eliminateCallFramePseudoInstr(MachineFunction &MF, + MachineBasicBlock &MBB, + MachineBasicBlock::iterator MI) const; + + /// If the register is X30 (i.e. LR) and the return address is used in the + /// function then the callee-save store doesn't actually kill the register, + /// otherwise it does. + bool determinePrologueDeath(MachineBasicBlock &MBB, unsigned Reg) const; + + /// This function emits the loads or stores required during prologue and + /// epilogue as efficiently as possible. + /// + /// The operations involved in setting up and tearing down the frame are + /// similar enough to warrant a shared function, particularly as discrepancies + /// between the two would be disastrous. + void emitFrameMemOps(bool isStore, MachineBasicBlock &MBB, + MachineBasicBlock::iterator MI, + const std::vector<CalleeSavedInfo> &CSI, + const TargetRegisterInfo *TRI, + LoadStoreMethod PossibleClasses[], + unsigned NumClasses) const; + + + virtual bool hasFP(const MachineFunction &MF) const; + + virtual bool useFPForAddressing(const MachineFunction &MF) const; + + /// On AA + virtual bool hasReservedCallFrame(const MachineFunction &MF) const; + +}; + +} // End llvm namespace + +#endif |