LLVM 20.0.0git
Mips16RegisterInfo.cpp
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1//===-- Mips16RegisterInfo.cpp - MIPS16 Register Information --------------===//
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 file contains the MIPS16 implementation of the TargetRegisterInfo class.
10//
11//===----------------------------------------------------------------------===//
12
13#include "Mips16RegisterInfo.h"
14#include "Mips.h"
15#include "Mips16InstrInfo.h"
16#include "MipsInstrInfo.h"
17#include "MipsMachineFunction.h"
18#include "MipsSubtarget.h"
19#include "llvm/ADT/STLExtras.h"
26#include "llvm/IR/Constants.h"
27#include "llvm/IR/DebugInfo.h"
28#include "llvm/IR/Function.h"
29#include "llvm/IR/Type.h"
30#include "llvm/Support/Debug.h"
35
36using namespace llvm;
37
38#define DEBUG_TYPE "mips16-registerinfo"
39
41
43 (const MachineFunction &MF) const {
44 return false;
45}
47 (const MachineFunction &MF) const {
48 return false;
49}
50
52 (const MachineFunction &MF) const {
53 return false;
54}
55
59 Register Reg) const {
62 TII.copyPhysReg(MBB, I, DL, Mips::T0, Reg, true);
63 TII.copyPhysReg(MBB, UseMI, DL, Reg, Mips::T0, true);
64 return true;
65}
66
69 assert(Size == 4);
70 return &Mips::CPU16RegsRegClass;
71}
72
73void Mips16RegisterInfo::eliminateFI(MachineBasicBlock::iterator II,
74 unsigned OpNo, int FrameIndex,
75 uint64_t StackSize,
76 int64_t SPOffset) const {
77 MachineInstr &MI = *II;
78 MachineFunction &MF = *MI.getParent()->getParent();
80
81 const std::vector<CalleeSavedInfo> &CSI = MFI.getCalleeSavedInfo();
82 int MinCSFI = 0;
83 int MaxCSFI = -1;
84
85 if (CSI.size()) {
86 MinCSFI = CSI[0].getFrameIdx();
87 MaxCSFI = CSI[CSI.size() - 1].getFrameIdx();
88 }
89
90 // The following stack frame objects are always
91 // referenced relative to $sp:
92 // 1. Outgoing arguments.
93 // 2. Pointer to dynamically allocated stack space.
94 // 3. Locations for callee-saved registers.
95 // Everything else is referenced relative to whatever register
96 // getFrameRegister() returns.
97 Register FrameReg;
98
99 if (FrameIndex >= MinCSFI && FrameIndex <= MaxCSFI)
100 FrameReg = Mips::SP;
101 else {
103 if (TFI->hasFP(MF)) {
104 FrameReg = Mips::S0;
105 }
106 else {
107 if ((MI.getNumOperands()> OpNo+2) && MI.getOperand(OpNo+2).isReg())
108 FrameReg = MI.getOperand(OpNo+2).getReg();
109 else
110 FrameReg = Mips::SP;
111 }
112 }
113 // Calculate final offset.
114 // - There is no need to change the offset if the frame object
115 // is one of the
116 // following: an outgoing argument, pointer to a dynamically allocated
117 // stack space or a $gp restore location,
118 // - If the frame object is any of the following,
119 // its offset must be adjusted
120 // by adding the size of the stack:
121 // incoming argument, callee-saved register location or local variable.
122 int64_t Offset;
123 bool IsKill = false;
124 Offset = SPOffset + (int64_t)StackSize;
125 Offset += MI.getOperand(OpNo + 1).getImm();
126
127 LLVM_DEBUG(errs() << "Offset : " << Offset << "\n"
128 << "<--------->\n");
129
130 if (!MI.isDebugValue() &&
131 !Mips16InstrInfo::validImmediate(MI.getOpcode(), FrameReg, Offset)) {
132 MachineBasicBlock &MBB = *MI.getParent();
133 DebugLoc DL = II->getDebugLoc();
134 unsigned NewImm;
135 const Mips16InstrInfo &TII =
136 *static_cast<const Mips16InstrInfo *>(MF.getSubtarget().getInstrInfo());
137 FrameReg = TII.loadImmediate(FrameReg, Offset, MBB, II, DL, NewImm);
138 Offset = SignExtend64<16>(NewImm);
139 IsKill = true;
140 }
141 MI.getOperand(OpNo).ChangeToRegister(FrameReg, false, false, IsKill);
142 MI.getOperand(OpNo + 1).ChangeToImmediate(Offset);
143
144
145}
MachineInstrBuilder & UseMI
MachineBasicBlock & MBB
MachineBasicBlock MachineBasicBlock::iterator DebugLoc DL
This file contains the declarations for the subclasses of Constant, which represent the different fla...
#define LLVM_DEBUG(X)
Definition: Debug.h:101
uint64_t Size
const HexagonInstrInfo * TII
IRTranslator LLVM IR MI
#define I(x, y, z)
Definition: MD5.cpp:58
uint64_t IntrinsicInst * II
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
This file contains some templates that are useful if you are working with the STL at all.
A debug info location.
Definition: DebugLoc.h:33
void copyPhysReg(MachineBasicBlock &MBB, MachineBasicBlock::iterator I, const DebugLoc &DL, MCRegister DestReg, MCRegister SrcReg, bool KillSrc) const override
Emit instructions to copy a pair of physical registers.
const MachineFunction * getParent() const
Return the MachineFunction containing this basic block.
The MachineFrameInfo class represents an abstract stack frame until prolog/epilog code is inserted.
const std::vector< CalleeSavedInfo > & getCalleeSavedInfo() const
Returns a reference to call saved info vector for the current function.
const TargetSubtargetInfo & getSubtarget() const
getSubtarget - Return the subtarget for which this machine code is being compiled.
MachineFrameInfo & getFrameInfo()
getFrameInfo - Return the frame info object for the current function.
Representation of each machine instruction.
Definition: MachineInstr.h:69
static bool validImmediate(unsigned Opcode, unsigned Reg, int64_t Amount)
bool requiresFrameIndexScavenging(const MachineFunction &MF) const override
bool useFPForScavengingIndex(const MachineFunction &MF) const override
bool saveScavengerRegister(MachineBasicBlock &MBB, MachineBasicBlock::iterator I, MachineBasicBlock::iterator &UseMI, const TargetRegisterClass *RC, Register Reg) const override
const TargetRegisterClass * intRegClass(unsigned Size) const override
Return GPR register class.
bool requiresRegisterScavenging(const MachineFunction &MF) const override
Wrapper class representing virtual and physical registers.
Definition: Register.h:19
Information about stack frame layout on the target.
virtual bool hasFP(const MachineFunction &MF) const =0
hasFP - Return true if the specified function should have a dedicated frame pointer register.
TargetInstrInfo - Interface to description of machine instruction set.
virtual const TargetFrameLowering * getFrameLowering() const
virtual const TargetInstrInfo * getInstrInfo() const
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18
@ Offset
Definition: DWP.cpp:480
raw_fd_ostream & errs()
This returns a reference to a raw_ostream for standard error.