1 //===-- SystemZFrameLowering.h - Frame lowering for SystemZ -----*- 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 //===----------------------------------------------------------------------===//
10 #ifndef SYSTEMZFRAMELOWERING_H
11 #define SYSTEMZFRAMELOWERING_H
13 #include "SystemZSubtarget.h"
14 #include "llvm/ADT/IndexedMap.h"
15 #include "llvm/Target/TargetFrameLowering.h"
18 class SystemZTargetMachine;
19 class SystemZSubtarget;
21 class SystemZFrameLowering : public TargetFrameLowering {
22 IndexedMap<unsigned> RegSpillOffsets;
25 const SystemZTargetMachine &TM;
26 const SystemZSubtarget &STI;
29 SystemZFrameLowering(const SystemZTargetMachine &tm,
30 const SystemZSubtarget &sti);
32 // Override TargetFrameLowering.
33 virtual const SpillSlot *getCalleeSavedSpillSlots(unsigned &NumEntries) const
36 processFunctionBeforeCalleeSavedScan(MachineFunction &MF,
37 RegScavenger *RS) const LLVM_OVERRIDE;
39 spillCalleeSavedRegisters(MachineBasicBlock &MBB,
40 MachineBasicBlock::iterator MBBI,
41 const std::vector<CalleeSavedInfo> &CSI,
42 const TargetRegisterInfo *TRI) const
45 restoreCalleeSavedRegisters(MachineBasicBlock &MBB,
46 MachineBasicBlock::iterator MBBII,
47 const std::vector<CalleeSavedInfo> &CSI,
48 const TargetRegisterInfo *TRI) const
50 virtual void emitPrologue(MachineFunction &MF) const LLVM_OVERRIDE;
51 virtual void emitEpilogue(MachineFunction &MF,
52 MachineBasicBlock &MBB) const LLVM_OVERRIDE;
53 virtual bool hasFP(const MachineFunction &MF) const LLVM_OVERRIDE;
54 virtual int getFrameIndexOffset(const MachineFunction &MF,
55 int FI) const LLVM_OVERRIDE;
56 virtual bool hasReservedCallFrame(const MachineFunction &MF) const
59 eliminateCallFramePseudoInstr(MachineFunction &MF,
60 MachineBasicBlock &MBB,
61 MachineBasicBlock::iterator MI) const
64 // Return the number of bytes in the callee-allocated part of the frame.
65 uint64_t getAllocatedStackSize(const MachineFunction &MF) const;
67 // Return the number of frame bytes that should be reserved for
68 // an emergency spill slot, for use by the register scaveneger.
69 // Return 0 if register scaveging won't be needed.
70 unsigned getEmergencySpillSlotSize(const MachineFunction &MF) const;
72 // Return the offset from the frame pointer of the emergency spill slot,
73 // which always fits within a 12-bit unsigned displacement field.
74 // Only valid if getEmergencySpillSlotSize(MF) returns nonzero.
75 unsigned getEmergencySpillSlotOffset(const MachineFunction &MF) const;
77 // Return the byte offset from the incoming stack pointer of Reg's
78 // ABI-defined save slot. Return 0 if no slot is defined for Reg.
79 unsigned getRegSpillOffset(unsigned Reg) const {
80 return RegSpillOffsets[Reg];
83 } // end namespace llvm