| //===-- SystemZFrameLowering.h - Frame lowering for SystemZ -----*- C++ -*-===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef SYSTEMZFRAMELOWERING_H |
| #define SYSTEMZFRAMELOWERING_H |
| |
| #include "SystemZSubtarget.h" |
| #include "llvm/ADT/IndexedMap.h" |
| #include "llvm/Target/TargetFrameLowering.h" |
| |
| namespace llvm { |
| class SystemZTargetMachine; |
| class SystemZSubtarget; |
| |
| class SystemZFrameLowering : public TargetFrameLowering { |
| IndexedMap<unsigned> RegSpillOffsets; |
| |
| protected: |
| const SystemZTargetMachine &TM; |
| const SystemZSubtarget &STI; |
| |
| public: |
| SystemZFrameLowering(const SystemZTargetMachine &tm, |
| const SystemZSubtarget &sti); |
| |
| // Override FrameLowering. |
| virtual void |
| processFunctionBeforeCalleeSavedScan(MachineFunction &MF, |
| RegScavenger *RS) const LLVM_OVERRIDE; |
| virtual bool |
| spillCalleeSavedRegisters(MachineBasicBlock &MBB, |
| MachineBasicBlock::iterator MBBI, |
| const std::vector<CalleeSavedInfo> &CSI, |
| const TargetRegisterInfo *TRI) const |
| LLVM_OVERRIDE; |
| virtual bool |
| restoreCalleeSavedRegisters(MachineBasicBlock &MBB, |
| MachineBasicBlock::iterator MBBII, |
| const std::vector<CalleeSavedInfo> &CSI, |
| const TargetRegisterInfo *TRI) const |
| LLVM_OVERRIDE; |
| virtual void emitPrologue(MachineFunction &MF) const LLVM_OVERRIDE; |
| virtual void emitEpilogue(MachineFunction &MF, |
| MachineBasicBlock &MBB) const LLVM_OVERRIDE; |
| virtual bool hasFP(const MachineFunction &MF) const LLVM_OVERRIDE; |
| virtual int getFrameIndexOffset(const MachineFunction &MF, |
| int FI) const LLVM_OVERRIDE; |
| virtual bool hasReservedCallFrame(const MachineFunction &MF) const |
| LLVM_OVERRIDE; |
| virtual void |
| eliminateCallFramePseudoInstr(MachineFunction &MF, |
| MachineBasicBlock &MBB, |
| MachineBasicBlock::iterator MI) const |
| LLVM_OVERRIDE; |
| |
| // The target-independent code automatically allocates save slots for |
| // call-saved GPRs. However, we don't need those slots for SystemZ, |
| // because the ABI sets aside GPR save slots in the caller-allocated part |
| // of the frame. Since the target-independent code puts this unneeded |
| // area at the top of the callee-allocated part of frame, we choose not |
| // to allocate it and adjust the offsets accordingly. Return the |
| // size of this unallocated area. |
| // FIXME: seems a bit hackish. |
| uint64_t getUnallocatedTopBytes(const MachineFunction &MF) const; |
| |
| // Return the number of bytes in the callee-allocated part of the frame. |
| uint64_t getAllocatedStackSize(const MachineFunction &MF) const; |
| |
| // Return the number of frame bytes that should be reserved for |
| // an emergency spill slot, for use by the register scaveneger. |
| // Return 0 if register scaveging won't be needed. |
| unsigned getEmergencySpillSlotSize(const MachineFunction &MF) const; |
| |
| // Return the offset from the frame pointer of the emergency spill slot, |
| // which always fits within a 12-bit unsigned displacement field. |
| // Only valid if getEmergencySpillSlotSize(MF) returns nonzero. |
| unsigned getEmergencySpillSlotOffset(const MachineFunction &MF) const; |
| |
| // Return the byte offset from the incoming stack pointer of Reg's |
| // ABI-defined save slot. Return 0 if no slot is defined for Reg. |
| unsigned getRegSpillOffset(unsigned Reg) const { |
| return RegSpillOffsets[Reg]; |
| } |
| }; |
| } // end namespace llvm |
| |
| #endif |
