LLVM 19.0.0git
ARMBaseRegisterInfo.h
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1//===-- ARMBaseRegisterInfo.h - ARM Register Information Impl ---*- 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 file contains the base ARM implementation of TargetRegisterInfo class.
10//
11//===----------------------------------------------------------------------===//
12
13#ifndef LLVM_LIB_TARGET_ARM_ARMBASEREGISTERINFO_H
14#define LLVM_LIB_TARGET_ARM_ARMBASEREGISTERINFO_H
15
20#include "llvm/IR/CallingConv.h"
22#include <cstdint>
23
24#define GET_REGINFO_HEADER
25#include "ARMGenRegisterInfo.inc"
26
27namespace llvm {
28
29class LiveIntervals;
30
31/// Register allocation hints.
32namespace ARMRI {
33
34 enum {
35 // Used for LDRD register pairs
38 // Used to hint for lr in t2DoLoopStart
39 RegLR = 3
40 };
41
42} // end namespace ARMRI
43
44/// isARMArea1Register - Returns true if the register is a low register (r0-r7)
45/// or a stack/pc register that we should push/pop.
46static inline bool isARMArea1Register(unsigned Reg, bool SplitFramePushPop) {
47 using namespace ARM;
48
49 switch (Reg) {
50 case R0: case R1: case R2: case R3:
51 case R4: case R5: case R6: case R7:
52 case LR: case SP: case PC:
53 return true;
54 case R8: case R9: case R10: case R11: case R12:
55 // For iOS we want r7 and lr to be next to each other.
56 return !SplitFramePushPop;
57 default:
58 return false;
59 }
60}
61
62static inline bool isARMArea2Register(unsigned Reg, bool SplitFramePushPop) {
63 using namespace ARM;
64
65 switch (Reg) {
66 case R8: case R9: case R10: case R11: case R12:
67 // iOS has this second area.
68 return SplitFramePushPop;
69 default:
70 return false;
71 }
72}
73
74static inline bool isSplitFPArea1Register(unsigned Reg,
75 bool SplitFramePushPop) {
76 using namespace ARM;
77
78 switch (Reg) {
79 case R0: case R1: case R2: case R3:
80 case R4: case R5: case R6: case R7:
81 case R8: case R9: case R10: case R12:
82 case SP: case PC:
83 return true;
84 default:
85 return false;
86 }
87}
88
89static inline bool isSplitFPArea2Register(unsigned Reg,
90 bool SplitFramePushPop) {
91 using namespace ARM;
92
93 switch (Reg) {
94 case R11: case LR:
95 return true;
96 default:
97 return false;
98 }
99}
100
101static inline bool isARMArea3Register(unsigned Reg, bool SplitFramePushPop) {
102 using namespace ARM;
103
104 switch (Reg) {
105 case D15: case D14: case D13: case D12:
106 case D11: case D10: case D9: case D8:
107 case D7: case D6: case D5: case D4:
108 case D3: case D2: case D1: case D0:
109 case D31: case D30: case D29: case D28:
110 case D27: case D26: case D25: case D24:
111 case D23: case D22: case D21: case D20:
112 case D19: case D18: case D17: case D16:
113 return true;
114 default:
115 return false;
116 }
117}
118
119static inline bool isCalleeSavedRegister(unsigned Reg,
120 const MCPhysReg *CSRegs) {
121 for (unsigned i = 0; CSRegs[i]; ++i)
122 if (Reg == CSRegs[i])
123 return true;
124 return false;
125}
126
128protected:
129 /// BasePtr - ARM physical register used as a base ptr in complex stack
130 /// frames. I.e., when we need a 3rd base, not just SP and FP, due to
131 /// variable size stack objects.
132 unsigned BasePtr = ARM::R6;
133
134 // Can be only subclassed.
135 explicit ARMBaseRegisterInfo();
136
137public:
138 /// Code Generation virtual methods...
139 const MCPhysReg *getCalleeSavedRegs(const MachineFunction *MF) const override;
140 const MCPhysReg *
143 CallingConv::ID) const override;
144 const uint32_t *getNoPreservedMask() const override;
145 const uint32_t *getTLSCallPreservedMask(const MachineFunction &MF) const;
147
148 /// getThisReturnPreservedMask - Returns a call preserved mask specific to the
149 /// case that 'returned' is on an i32 first argument if the calling convention
150 /// is one that can (partially) model this attribute with a preserved mask
151 /// (i.e. it is a calling convention that uses the same register for the first
152 /// i32 argument and an i32 return value)
153 ///
154 /// Should return NULL in the case that the calling convention does not have
155 /// this property
157 CallingConv::ID) const;
158
160 getIntraCallClobberedRegs(const MachineFunction *MF) const override;
161
162 BitVector getReservedRegs(const MachineFunction &MF) const override;
163 bool isAsmClobberable(const MachineFunction &MF,
164 MCRegister PhysReg) const override;
166 unsigned PhysReg) const override;
167
168 const TargetRegisterClass *
170 unsigned Kind = 0) const override;
171 const TargetRegisterClass *
172 getCrossCopyRegClass(const TargetRegisterClass *RC) const override;
173
174 const TargetRegisterClass *
176 const MachineFunction &MF) const override;
177
178 unsigned getRegPressureLimit(const TargetRegisterClass *RC,
179 MachineFunction &MF) const override;
180
183 const MachineFunction &MF, const VirtRegMap *VRM,
184 const LiveRegMatrix *Matrix) const override;
185
187 MachineFunction &MF) const override;
188
189 bool hasBasePointer(const MachineFunction &MF) const;
190
191 bool canRealignStack(const MachineFunction &MF) const override;
193 int Idx) const override;
194 bool needsFrameBaseReg(MachineInstr *MI, int64_t Offset) const override;
196 int64_t Offset) const override;
198 int64_t Offset) const override;
199 bool isFrameOffsetLegal(const MachineInstr *MI, Register BaseReg,
200 int64_t Offset) const override;
201
202 bool cannotEliminateFrame(const MachineFunction &MF) const;
203
204 // Debug information queries.
205 Register getFrameRegister(const MachineFunction &MF) const override;
206 Register getBaseRegister() const { return BasePtr; }
207
208 /// emitLoadConstPool - Emits a load from constpool to materialize the
209 /// specified immediate.
210 virtual void
212 const DebugLoc &dl, Register DestReg, unsigned SubIdx,
213 int Val, ARMCC::CondCodes Pred = ARMCC::AL,
214 Register PredReg = Register(),
215 unsigned MIFlags = MachineInstr::NoFlags) const;
216
217 /// Code Generation virtual methods...
218 bool requiresRegisterScavenging(const MachineFunction &MF) const override;
219
220 bool requiresFrameIndexScavenging(const MachineFunction &MF) const override;
221
222 bool requiresVirtualBaseRegisters(const MachineFunction &MF) const override;
223
225 int SPAdj, unsigned FIOperandNum,
226 RegScavenger *RS = nullptr) const override;
227
228 /// SrcRC and DstRC will be morphed into NewRC if this returns true
230 const TargetRegisterClass *SrcRC,
231 unsigned SubReg,
232 const TargetRegisterClass *DstRC,
233 unsigned DstSubReg,
234 const TargetRegisterClass *NewRC,
235 LiveIntervals &LIS) const override;
236
238 unsigned DefSubReg,
239 const TargetRegisterClass *SrcRC,
240 unsigned SrcSubReg) const override;
241
242 int getSEHRegNum(unsigned i) const { return getEncodingValue(i); }
243
244 const TargetRegisterClass *
245 getLargestSuperClass(const TargetRegisterClass *RC) const override {
246 if (ARM::MQPRRegClass.hasSubClassEq(RC))
247 return &ARM::MQPRRegClass;
248 if (ARM::SPRRegClass.hasSubClassEq(RC))
249 return &ARM::SPRRegClass;
250 if (ARM::DPR_VFP2RegClass.hasSubClassEq(RC))
251 return &ARM::DPR_VFP2RegClass;
252 if (ARM::GPRRegClass.hasSubClassEq(RC))
253 return &ARM::GPRRegClass;
254 return RC;
255 }
256
258 const TargetRegisterClass *RC) const override {
259 (void)RC;
260 // For the ARM Architecture we want to always return true because all
261 // required PseudoInitUndef types have been added. If compilation fails due
262 // to `Unexpected register class`, this is likely to be because the specific
263 // register being used is not support by Init Undef and needs the Pseudo
264 // Instruction adding to ARMInstrInfo.td. If this is implemented as a
265 // conditional check, this could create a false positive where Init Undef is
266 // not running, skipping the instruction and moving to the next. This could
267 // lead to illegal instructions being generated by the register allocator.
268 return true;
269 }
270};
271
272} // end namespace llvm
273
274#endif // LLVM_LIB_TARGET_ARM_ARMBASEREGISTERINFO_H
unsigned SubReg
MachineBasicBlock & MBB
MachineBasicBlock MachineBasicBlock::iterator MBBI
Returns the sub type a function will return at a given Idx Should correspond to the result type of an ExtractValue instruction executed with just that one unsigned Idx
IRTranslator LLVM IR MI
Live Register Matrix
unsigned Reg
#define R4(n)
#define R2(n)
#define R6(n)
bool shouldCoalesce(MachineInstr *MI, const TargetRegisterClass *SrcRC, unsigned SubReg, const TargetRegisterClass *DstRC, unsigned DstSubReg, const TargetRegisterClass *NewRC, LiveIntervals &LIS) const override
SrcRC and DstRC will be morphed into NewRC if this returns true.
bool hasBasePointer(const MachineFunction &MF) const
bool isFrameOffsetLegal(const MachineInstr *MI, Register BaseReg, int64_t Offset) const override
BitVector getReservedRegs(const MachineFunction &MF) const override
int64_t getFrameIndexInstrOffset(const MachineInstr *MI, int Idx) const override
void updateRegAllocHint(Register Reg, Register NewReg, MachineFunction &MF) const override
const uint32_t * getNoPreservedMask() const override
bool shouldRewriteCopySrc(const TargetRegisterClass *DefRC, unsigned DefSubReg, const TargetRegisterClass *SrcRC, unsigned SrcSubReg) const override
bool requiresVirtualBaseRegisters(const MachineFunction &MF) const override
const TargetRegisterClass * getLargestSuperClass(const TargetRegisterClass *RC) const override
virtual void emitLoadConstPool(MachineBasicBlock &MBB, MachineBasicBlock::iterator &MBBI, const DebugLoc &dl, Register DestReg, unsigned SubIdx, int Val, ARMCC::CondCodes Pred=ARMCC::AL, Register PredReg=Register(), unsigned MIFlags=MachineInstr::NoFlags) const
emitLoadConstPool - Emits a load from constpool to materialize the specified immediate.
const uint32_t * getSjLjDispatchPreservedMask(const MachineFunction &MF) const
bool eliminateFrameIndex(MachineBasicBlock::iterator II, int SPAdj, unsigned FIOperandNum, RegScavenger *RS=nullptr) const override
bool getRegAllocationHints(Register VirtReg, ArrayRef< MCPhysReg > Order, SmallVectorImpl< MCPhysReg > &Hints, const MachineFunction &MF, const VirtRegMap *VRM, const LiveRegMatrix *Matrix) const override
const TargetRegisterClass * getLargestLegalSuperClass(const TargetRegisterClass *RC, const MachineFunction &MF) const override
int getSEHRegNum(unsigned i) const
const MCPhysReg * getCalleeSavedRegs(const MachineFunction *MF) const override
Code Generation virtual methods...
bool cannotEliminateFrame(const MachineFunction &MF) const
bool doesRegClassHavePseudoInitUndef(const TargetRegisterClass *RC) const override
Register getFrameRegister(const MachineFunction &MF) const override
bool isAsmClobberable(const MachineFunction &MF, MCRegister PhysReg) const override
const uint32_t * getCallPreservedMask(const MachineFunction &MF, CallingConv::ID) const override
Register materializeFrameBaseRegister(MachineBasicBlock *MBB, int FrameIdx, int64_t Offset) const override
materializeFrameBaseRegister - Insert defining instruction(s) for BaseReg to be a pointer to FrameIdx...
bool requiresRegisterScavenging(const MachineFunction &MF) const override
Code Generation virtual methods...
const uint32_t * getTLSCallPreservedMask(const MachineFunction &MF) const
void resolveFrameIndex(MachineInstr &MI, Register BaseReg, int64_t Offset) const override
const TargetRegisterClass * getPointerRegClass(const MachineFunction &MF, unsigned Kind=0) const override
unsigned BasePtr
BasePtr - ARM physical register used as a base ptr in complex stack frames.
bool isInlineAsmReadOnlyReg(const MachineFunction &MF, unsigned PhysReg) const override
ArrayRef< MCPhysReg > getIntraCallClobberedRegs(const MachineFunction *MF) const override
const TargetRegisterClass * getCrossCopyRegClass(const TargetRegisterClass *RC) const override
const MCPhysReg * getCalleeSavedRegsViaCopy(const MachineFunction *MF) const
bool needsFrameBaseReg(MachineInstr *MI, int64_t Offset) const override
needsFrameBaseReg - Returns true if the instruction's frame index reference would be better served by...
const uint32_t * getThisReturnPreservedMask(const MachineFunction &MF, CallingConv::ID) const
getThisReturnPreservedMask - Returns a call preserved mask specific to the case that 'returned' is on...
bool canRealignStack(const MachineFunction &MF) const override
unsigned getRegPressureLimit(const TargetRegisterClass *RC, MachineFunction &MF) const override
bool requiresFrameIndexScavenging(const MachineFunction &MF) const override
ArrayRef - Represent a constant reference to an array (0 or more elements consecutively in memory),...
Definition: ArrayRef.h:41
A debug info location.
Definition: DebugLoc.h:33
Wrapper class representing physical registers. Should be passed by value.
Definition: MCRegister.h:33
Representation of each machine instruction.
Definition: MachineInstr.h:69
Wrapper class representing virtual and physical registers.
Definition: Register.h:19
This class consists of common code factored out of the SmallVector class to reduce code duplication b...
Definition: SmallVector.h:586
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18
@ Offset
Definition: DWP.cpp:456
static bool isSplitFPArea1Register(unsigned Reg, bool SplitFramePushPop)
static bool isARMArea2Register(unsigned Reg, bool SplitFramePushPop)
static bool isARMArea3Register(unsigned Reg, bool SplitFramePushPop)
static bool isCalleeSavedRegister(unsigned Reg, const MCPhysReg *CSRegs)
static bool isARMArea1Register(unsigned Reg, bool SplitFramePushPop)
isARMArea1Register - Returns true if the register is a low register (r0-r7) or a stack/pc register th...
static bool isSplitFPArea2Register(unsigned Reg, bool SplitFramePushPop)