1 //===-- SystemZFrameLowering.h - Frame lowering for SystemZ -----*- 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-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #ifndef LLVM_LIB_TARGET_SYSTEMZ_SYSTEMZFRAMELOWERING_H
10 #define LLVM_LIB_TARGET_SYSTEMZ_SYSTEMZFRAMELOWERING_H
11 
12 #include "llvm/ADT/IndexedMap.h"
13 #include "llvm/CodeGen/TargetFrameLowering.h"
14 #include "llvm/Support/TypeSize.h"
15 
16 namespace llvm {
17 class SystemZTargetMachine;
18 class SystemZSubtarget;
19 
20 class SystemZFrameLowering : public TargetFrameLowering {
21   IndexedMap<unsigned> RegSpillOffsets;
22 
23 public:
24   SystemZFrameLowering();
25 
26   // Override TargetFrameLowering.
isFPCloseToIncomingSP()27   bool isFPCloseToIncomingSP() const override { return false; }
28   bool
29   assignCalleeSavedSpillSlots(MachineFunction &MF,
30                               const TargetRegisterInfo *TRI,
31                               std::vector<CalleeSavedInfo> &CSI) const override;
32   void determineCalleeSaves(MachineFunction &MF, BitVector &SavedRegs,
33                             RegScavenger *RS) const override;
34   bool spillCalleeSavedRegisters(MachineBasicBlock &MBB,
35                                  MachineBasicBlock::iterator MBBI,
36                                  ArrayRef<CalleeSavedInfo> CSI,
37                                  const TargetRegisterInfo *TRI) const override;
38   bool
39   restoreCalleeSavedRegisters(MachineBasicBlock &MBB,
40                               MachineBasicBlock::iterator MBBII,
41                               MutableArrayRef<CalleeSavedInfo> CSI,
42                               const TargetRegisterInfo *TRI) const override;
43   void processFunctionBeforeFrameFinalized(MachineFunction &MF,
44                                            RegScavenger *RS) const override;
45   void emitPrologue(MachineFunction &MF, MachineBasicBlock &MBB) const override;
46   void emitEpilogue(MachineFunction &MF, MachineBasicBlock &MBB) const override;
47   void inlineStackProbe(MachineFunction &MF,
48                         MachineBasicBlock &PrologMBB) const override;
49   bool hasFP(const MachineFunction &MF) const override;
50   bool hasReservedCallFrame(const MachineFunction &MF) const override;
51   StackOffset getFrameIndexReference(const MachineFunction &MF, int FI,
52                                      Register &FrameReg) const override;
53   MachineBasicBlock::iterator
54   eliminateCallFramePseudoInstr(MachineFunction &MF, MachineBasicBlock &MBB,
55                                 MachineBasicBlock::iterator MI) const override;
56 
57   // Return the byte offset from the incoming stack pointer of Reg's
58   // ABI-defined save slot.  Return 0 if no slot is defined for Reg.  Adjust
59   // the offset in case MF has packed-stack.
60   unsigned getRegSpillOffset(MachineFunction &MF, Register Reg) const;
61 
62   // Get or create the frame index of where the old frame pointer is stored.
63   int getOrCreateFramePointerSaveIndex(MachineFunction &MF) const;
64 
65   bool usePackedStack(MachineFunction &MF) const;
66 };
67 } // end namespace llvm
68 
69 #endif
70