1 //===- ARMRegisterBankInfo.cpp -----------------------------------*- 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 /// This file implements the targeting of the RegisterBankInfo class for ARM.
11 /// \todo This should be generated by TableGen.
12 //===----------------------------------------------------------------------===//
14 #include "ARMRegisterBankInfo.h"
15 #include "ARMInstrInfo.h" // For the register classes
16 #include "ARMSubtarget.h"
17 #include "llvm/CodeGen/GlobalISel/RegisterBank.h"
18 #include "llvm/CodeGen/GlobalISel/RegisterBankInfo.h"
19 #include "llvm/CodeGen/MachineRegisterInfo.h"
20 #include "llvm/Target/TargetRegisterInfo.h"
22 #define GET_TARGET_REGBANK_IMPL
23 #include "ARMGenRegisterBank.inc"
27 #ifndef LLVM_BUILD_GLOBAL_ISEL
28 #error "You shouldn't build this"
31 // FIXME: TableGen this.
32 // If it grows too much and TableGen still isn't ready to do the job, extract it
33 // into an ARMGenRegisterBankInfo.def (similar to AArch64).
36 enum PartialMappingIdx {
43 RegisterBankInfo::PartialMapping PartMappings[]{
44 // GPR Partial Mapping
46 // SPR Partial Mapping
48 // DPR Partial Mapping
53 static bool checkPartMapping(const RegisterBankInfo::PartialMapping &PM,
54 unsigned Start, unsigned Length,
56 return PM.StartIdx == Start && PM.Length == Length &&
57 PM.RegBank->getID() == RegBankID;
60 static void checkPartialMappings() {
62 checkPartMapping(PartMappings[PMI_GPR - PMI_Min], 0, 32, GPRRegBankID) &&
63 "Wrong mapping for GPR");
65 checkPartMapping(PartMappings[PMI_SPR - PMI_Min], 0, 32, FPRRegBankID) &&
66 "Wrong mapping for SPR");
68 checkPartMapping(PartMappings[PMI_DPR - PMI_Min], 0, 64, FPRRegBankID) &&
69 "Wrong mapping for DPR");
73 enum ValueMappingIdx {
80 RegisterBankInfo::ValueMapping ValueMappings[] = {
84 {&PartMappings[PMI_GPR - PMI_Min], 1},
85 {&PartMappings[PMI_GPR - PMI_Min], 1},
86 {&PartMappings[PMI_GPR - PMI_Min], 1},
88 {&PartMappings[PMI_SPR - PMI_Min], 1},
89 {&PartMappings[PMI_SPR - PMI_Min], 1},
90 {&PartMappings[PMI_SPR - PMI_Min], 1},
92 {&PartMappings[PMI_DPR - PMI_Min], 1},
93 {&PartMappings[PMI_DPR - PMI_Min], 1},
94 {&PartMappings[PMI_DPR - PMI_Min], 1}};
97 static bool checkValueMapping(const RegisterBankInfo::ValueMapping &VM,
98 RegisterBankInfo::PartialMapping *BreakDown) {
99 return VM.NumBreakDowns == 1 && VM.BreakDown == BreakDown;
102 static void checkValueMappings() {
103 assert(checkValueMapping(ValueMappings[GPR3OpsIdx],
104 &PartMappings[PMI_GPR - PMI_Min]) &&
105 "Wrong value mapping for 3 GPR ops instruction");
106 assert(checkValueMapping(ValueMappings[GPR3OpsIdx + 1],
107 &PartMappings[PMI_GPR - PMI_Min]) &&
108 "Wrong value mapping for 3 GPR ops instruction");
109 assert(checkValueMapping(ValueMappings[GPR3OpsIdx + 2],
110 &PartMappings[PMI_GPR - PMI_Min]) &&
111 "Wrong value mapping for 3 GPR ops instruction");
113 assert(checkValueMapping(ValueMappings[SPR3OpsIdx],
114 &PartMappings[PMI_SPR - PMI_Min]) &&
115 "Wrong value mapping for 3 SPR ops instruction");
116 assert(checkValueMapping(ValueMappings[SPR3OpsIdx + 1],
117 &PartMappings[PMI_SPR - PMI_Min]) &&
118 "Wrong value mapping for 3 SPR ops instruction");
119 assert(checkValueMapping(ValueMappings[SPR3OpsIdx + 2],
120 &PartMappings[PMI_SPR - PMI_Min]) &&
121 "Wrong value mapping for 3 SPR ops instruction");
123 assert(checkValueMapping(ValueMappings[DPR3OpsIdx],
124 &PartMappings[PMI_DPR - PMI_Min]) &&
125 "Wrong value mapping for 3 DPR ops instruction");
126 assert(checkValueMapping(ValueMappings[DPR3OpsIdx + 1],
127 &PartMappings[PMI_DPR - PMI_Min]) &&
128 "Wrong value mapping for 3 DPR ops instruction");
129 assert(checkValueMapping(ValueMappings[DPR3OpsIdx + 2],
130 &PartMappings[PMI_DPR - PMI_Min]) &&
131 "Wrong value mapping for 3 DPR ops instruction");
134 } // end namespace arm
135 } // end namespace llvm
137 ARMRegisterBankInfo::ARMRegisterBankInfo(const TargetRegisterInfo &TRI)
138 : ARMGenRegisterBankInfo() {
139 static bool AlreadyInit = false;
140 // We have only one set of register banks, whatever the subtarget
141 // is. Therefore, the initialization of the RegBanks table should be
142 // done only once. Indeed the table of all register banks
143 // (ARM::RegBanks) is unique in the compiler. At some point, it
144 // will get tablegen'ed and the whole constructor becomes empty.
149 const RegisterBank &RBGPR = getRegBank(ARM::GPRRegBankID);
151 assert(&ARM::GPRRegBank == &RBGPR && "The order in RegBanks is messed up");
153 // Initialize the GPR bank.
154 assert(RBGPR.covers(*TRI.getRegClass(ARM::GPRRegClassID)) &&
155 "Subclass not added?");
156 assert(RBGPR.covers(*TRI.getRegClass(ARM::GPRwithAPSRRegClassID)) &&
157 "Subclass not added?");
158 assert(RBGPR.covers(*TRI.getRegClass(ARM::GPRnopcRegClassID)) &&
159 "Subclass not added?");
160 assert(RBGPR.covers(*TRI.getRegClass(ARM::rGPRRegClassID)) &&
161 "Subclass not added?");
162 assert(RBGPR.covers(*TRI.getRegClass(ARM::tGPRRegClassID)) &&
163 "Subclass not added?");
164 assert(RBGPR.covers(*TRI.getRegClass(ARM::tcGPRRegClassID)) &&
165 "Subclass not added?");
166 assert(RBGPR.covers(*TRI.getRegClass(ARM::tGPR_and_tcGPRRegClassID)) &&
167 "Subclass not added?");
168 assert(RBGPR.getSize() == 32 && "GPRs should hold up to 32-bit");
171 ARM::checkPartialMappings();
172 ARM::checkValueMappings();
176 const RegisterBank &ARMRegisterBankInfo::getRegBankFromRegClass(
177 const TargetRegisterClass &RC) const {
180 switch (RC.getID()) {
182 case GPRnopcRegClassID:
183 case GPRspRegClassID:
184 case tGPR_and_tcGPRRegClassID:
186 return getRegBank(ARM::GPRRegBankID);
187 case SPR_8RegClassID:
189 case DPR_8RegClassID:
191 return getRegBank(ARM::FPRRegBankID);
193 llvm_unreachable("Unsupported register kind");
196 llvm_unreachable("Switch should handle all register classes");
199 RegisterBankInfo::InstructionMapping
200 ARMRegisterBankInfo::getInstrMapping(const MachineInstr &MI) const {
201 auto Opc = MI.getOpcode();
203 // Try the default logic for non-generic instructions that are either copies
204 // or already have some operands assigned to banks.
205 if (!isPreISelGenericOpcode(Opc)) {
206 InstructionMapping Mapping = getInstrMappingImpl(MI);
207 if (Mapping.isValid())
211 using namespace TargetOpcode;
213 const MachineFunction &MF = *MI.getParent()->getParent();
214 const MachineRegisterInfo &MRI = MF.getRegInfo();
215 LLT Ty = MRI.getType(MI.getOperand(0).getReg());
217 unsigned NumOperands = MI.getNumOperands();
218 const ValueMapping *OperandsMapping = &ARM::ValueMappings[ARM::GPR3OpsIdx];
230 // FIXME: We're abusing the fact that everything lives in a GPR for now; in
231 // the real world we would use different mappings.
232 OperandsMapping = &ARM::ValueMappings[ARM::GPR3OpsIdx];
237 Ty.getSizeInBits() == 64
238 ? getOperandsMapping({&ARM::ValueMappings[ARM::DPR3OpsIdx],
239 &ARM::ValueMappings[ARM::GPR3OpsIdx]})
240 : &ARM::ValueMappings[ARM::GPR3OpsIdx];
243 assert((Ty.getSizeInBits() == 32 || Ty.getSizeInBits() == 64) &&
244 "Unsupported size for G_FADD");
245 OperandsMapping = Ty.getSizeInBits() == 64
246 ? &ARM::ValueMappings[ARM::DPR3OpsIdx]
247 : &ARM::ValueMappings[ARM::SPR3OpsIdx];
252 getOperandsMapping({&ARM::ValueMappings[ARM::GPR3OpsIdx], nullptr});
255 // We only support G_SEQUENCE for creating a double precision floating point
256 // value out of two GPRs.
257 LLT Ty1 = MRI.getType(MI.getOperand(1).getReg());
258 LLT Ty2 = MRI.getType(MI.getOperand(3).getReg());
259 if (Ty.getSizeInBits() != 64 || Ty1.getSizeInBits() != 32 ||
260 Ty2.getSizeInBits() != 32)
261 return InstructionMapping{};
263 getOperandsMapping({&ARM::ValueMappings[ARM::DPR3OpsIdx],
264 &ARM::ValueMappings[ARM::GPR3OpsIdx], nullptr,
265 &ARM::ValueMappings[ARM::GPR3OpsIdx], nullptr});
269 // We only support G_EXTRACT for splitting a double precision floating point
270 // value into two GPRs.
271 LLT Ty1 = MRI.getType(MI.getOperand(1).getReg());
272 if (Ty.getSizeInBits() != 32 || Ty1.getSizeInBits() != 64 ||
273 MI.getOperand(2).getImm() % 32 != 0)
274 return InstructionMapping{};
275 OperandsMapping = getOperandsMapping({&ARM::ValueMappings[ARM::GPR3OpsIdx],
276 &ARM::ValueMappings[ARM::DPR3OpsIdx],
281 return InstructionMapping{};
285 for (unsigned i = 0; i < NumOperands; i++) {
286 for (const auto &Mapping : OperandsMapping[i]) {
288 (Mapping.RegBank->getID() != ARM::FPRRegBankID ||
289 MF.getSubtarget<ARMSubtarget>().hasVFP2()) &&
290 "Trying to use floating point register bank on target without vfp");
295 return InstructionMapping{DefaultMappingID, /*Cost=*/1, OperandsMapping,