1 //===-- VEFrameLowering.h - Define frame lowering for VE --*- 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 // This class implements VE-specific bits of TargetFrameLowering class.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #ifndef LLVM_LIB_TARGET_VE_VEFRAMELOWERING_H
14 #define LLVM_LIB_TARGET_VE_VEFRAMELOWERING_H
15 
16 #include "VE.h"
17 #include "llvm/CodeGen/TargetFrameLowering.h"
18 #include "llvm/Support/TypeSize.h"
19 
20 namespace llvm {
21 
22 class VESubtarget;
23 class VEFrameLowering : public TargetFrameLowering {
24 public:
25   explicit VEFrameLowering(const VESubtarget &ST);
26 
27   /// emitProlog/emitEpilog - These methods insert prolog and epilog code into
28   /// the function.
29   void emitPrologue(MachineFunction &MF, MachineBasicBlock &MBB) const override;
30   void emitEpilogue(MachineFunction &MF, MachineBasicBlock &MBB) const override;
31   void emitPrologueInsns(MachineFunction &MF, MachineBasicBlock &MBB,
32                          MachineBasicBlock::iterator MBBI, uint64_t NumBytes,
33                          bool RequireFPUpdate) const;
34   void emitEpilogueInsns(MachineFunction &MF, MachineBasicBlock &MBB,
35                          MachineBasicBlock::iterator MBBI, uint64_t NumBytes,
36                          bool RequireFPUpdate) const;
37 
38   MachineBasicBlock::iterator
39   eliminateCallFramePseudoInstr(MachineFunction &MF, MachineBasicBlock &MBB,
40                                 MachineBasicBlock::iterator I) const override;
41 
42   bool hasFP(const MachineFunction &MF) const override;
43   bool hasBP(const MachineFunction &MF) const;
44   bool hasGOT(const MachineFunction &MF) const;
45 
46   // VE reserves argument space always for call sites in the function
47   // immediately on entry of the current function.
48   bool hasReservedCallFrame(const MachineFunction &MF) const override {
49     return true;
50   }
51   void determineCalleeSaves(MachineFunction &MF, BitVector &SavedRegs,
52                             RegScavenger *RS = nullptr) const override;
53 
54   StackOffset getFrameIndexReference(const MachineFunction &MF, int FI,
55                                      Register &FrameReg) const override;
56 
57   const SpillSlot *
58   getCalleeSavedSpillSlots(unsigned &NumEntries) const override {
59     static const SpillSlot Offsets[] = {
60         {VE::SX17, 40},  {VE::SX18, 48},  {VE::SX19, 56},  {VE::SX20, 64},
61         {VE::SX21, 72},  {VE::SX22, 80},  {VE::SX23, 88},  {VE::SX24, 96},
62         {VE::SX25, 104}, {VE::SX26, 112}, {VE::SX27, 120}, {VE::SX28, 128},
63         {VE::SX29, 136}, {VE::SX30, 144}, {VE::SX31, 152}, {VE::SX32, 160},
64         {VE::SX33, 168}};
65     NumEntries = std::size(Offsets);
66     return Offsets;
67   }
68 
69 protected:
70   const VESubtarget &STI;
71 
72 private:
73   // Returns true if MF is a leaf procedure.
74   bool isLeafProc(MachineFunction &MF) const;
75 
76   // Emits code for adjusting SP in function prologue/epilogue.
77   void emitSPAdjustment(MachineFunction &MF, MachineBasicBlock &MBB,
78                         MachineBasicBlock::iterator MBBI, int64_t NumBytes,
79                         MaybeAlign MayAlign = MaybeAlign()) const;
80 
81   // Emits code for extending SP in function prologue/epilogue.
82   void emitSPExtend(MachineFunction &MF, MachineBasicBlock &MBB,
83                     MachineBasicBlock::iterator MBBI) const;
84 };
85 
86 } // namespace llvm
87 
88 #endif
89