1 //===- ARMBaseInstrInfo.h - ARM Base Instruction Information ----*- C++ -*-===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // This file contains the Base ARM implementation of the TargetInstrInfo class. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #ifndef ARMBASEINSTRUCTIONINFO_H 15 #define ARMBASEINSTRUCTIONINFO_H 16 17 #include "ARM.h" 18 #include "llvm/CodeGen/MachineInstrBuilder.h" 19 #include "llvm/Target/TargetInstrInfo.h" 20 #include "llvm/ADT/DenseMap.h" 21 #include "llvm/ADT/SmallSet.h" 22 23 #define GET_INSTRINFO_HEADER 24 #include "ARMGenInstrInfo.inc" 25 26 namespace llvm { 27 class ARMSubtarget; 28 class ARMBaseRegisterInfo; 29 30 class ARMBaseInstrInfo : public ARMGenInstrInfo { 31 const ARMSubtarget &Subtarget; 32 33 protected: 34 // Can be only subclassed. 35 explicit ARMBaseInstrInfo(const ARMSubtarget &STI); 36 37 public: 38 // Return the non-pre/post incrementing version of 'Opc'. Return 0 39 // if there is not such an opcode. 40 virtual unsigned getUnindexedOpcode(unsigned Opc) const =0; 41 42 virtual MachineInstr *convertToThreeAddress(MachineFunction::iterator &MFI, 43 MachineBasicBlock::iterator &MBBI, 44 LiveVariables *LV) const; 45 46 virtual const ARMBaseRegisterInfo &getRegisterInfo() const =0; 47 const ARMSubtarget &getSubtarget() const { return Subtarget; } 48 49 ScheduleHazardRecognizer * 50 CreateTargetHazardRecognizer(const TargetMachine *TM, 51 const ScheduleDAG *DAG) const; 52 53 ScheduleHazardRecognizer * 54 CreateTargetPostRAHazardRecognizer(const InstrItineraryData *II, 55 const ScheduleDAG *DAG) const; 56 57 // Branch analysis. 58 virtual bool AnalyzeBranch(MachineBasicBlock &MBB, MachineBasicBlock *&TBB, 59 MachineBasicBlock *&FBB, 60 SmallVectorImpl<MachineOperand> &Cond, 61 bool AllowModify = false) const; 62 virtual unsigned RemoveBranch(MachineBasicBlock &MBB) const; 63 virtual unsigned InsertBranch(MachineBasicBlock &MBB, MachineBasicBlock *TBB, 64 MachineBasicBlock *FBB, 65 const SmallVectorImpl<MachineOperand> &Cond, 66 DebugLoc DL) const; 67 68 virtual 69 bool ReverseBranchCondition(SmallVectorImpl<MachineOperand> &Cond) const; 70 71 // Predication support. 72 bool isPredicated(const MachineInstr *MI) const { 73 int PIdx = MI->findFirstPredOperandIdx(); 74 return PIdx != -1 && MI->getOperand(PIdx).getImm() != ARMCC::AL; 75 } 76 77 ARMCC::CondCodes getPredicate(const MachineInstr *MI) const { 78 int PIdx = MI->findFirstPredOperandIdx(); 79 return PIdx != -1 ? (ARMCC::CondCodes)MI->getOperand(PIdx).getImm() 80 : ARMCC::AL; 81 } 82 83 virtual 84 bool PredicateInstruction(MachineInstr *MI, 85 const SmallVectorImpl<MachineOperand> &Pred) const; 86 87 virtual 88 bool SubsumesPredicate(const SmallVectorImpl<MachineOperand> &Pred1, 89 const SmallVectorImpl<MachineOperand> &Pred2) const; 90 91 virtual bool DefinesPredicate(MachineInstr *MI, 92 std::vector<MachineOperand> &Pred) const; 93 94 virtual bool isPredicable(MachineInstr *MI) const; 95 96 /// GetInstSize - Returns the size of the specified MachineInstr. 97 /// 98 virtual unsigned GetInstSizeInBytes(const MachineInstr* MI) const; 99 100 virtual unsigned isLoadFromStackSlot(const MachineInstr *MI, 101 int &FrameIndex) const; 102 virtual unsigned isStoreToStackSlot(const MachineInstr *MI, 103 int &FrameIndex) const; 104 virtual unsigned isLoadFromStackSlotPostFE(const MachineInstr *MI, 105 int &FrameIndex) const; 106 virtual unsigned isStoreToStackSlotPostFE(const MachineInstr *MI, 107 int &FrameIndex) const; 108 109 virtual void copyPhysReg(MachineBasicBlock &MBB, 110 MachineBasicBlock::iterator I, DebugLoc DL, 111 unsigned DestReg, unsigned SrcReg, 112 bool KillSrc) const; 113 114 virtual void storeRegToStackSlot(MachineBasicBlock &MBB, 115 MachineBasicBlock::iterator MBBI, 116 unsigned SrcReg, bool isKill, int FrameIndex, 117 const TargetRegisterClass *RC, 118 const TargetRegisterInfo *TRI) const; 119 120 virtual void loadRegFromStackSlot(MachineBasicBlock &MBB, 121 MachineBasicBlock::iterator MBBI, 122 unsigned DestReg, int FrameIndex, 123 const TargetRegisterClass *RC, 124 const TargetRegisterInfo *TRI) const; 125 126 virtual bool expandPostRAPseudo(MachineBasicBlock::iterator MI) const; 127 128 virtual MachineInstr *emitFrameIndexDebugValue(MachineFunction &MF, 129 int FrameIx, 130 uint64_t Offset, 131 const MDNode *MDPtr, 132 DebugLoc DL) const; 133 134 virtual void reMaterialize(MachineBasicBlock &MBB, 135 MachineBasicBlock::iterator MI, 136 unsigned DestReg, unsigned SubIdx, 137 const MachineInstr *Orig, 138 const TargetRegisterInfo &TRI) const; 139 140 MachineInstr *duplicate(MachineInstr *Orig, MachineFunction &MF) const; 141 142 virtual bool produceSameValue(const MachineInstr *MI0, 143 const MachineInstr *MI1, 144 const MachineRegisterInfo *MRI) const; 145 146 /// areLoadsFromSameBasePtr - This is used by the pre-regalloc scheduler to 147 /// determine if two loads are loading from the same base address. It should 148 /// only return true if the base pointers are the same and the only 149 /// differences between the two addresses is the offset. It also returns the 150 /// offsets by reference. 151 virtual bool areLoadsFromSameBasePtr(SDNode *Load1, SDNode *Load2, 152 int64_t &Offset1, int64_t &Offset2)const; 153 154 /// shouldScheduleLoadsNear - This is a used by the pre-regalloc scheduler to 155 /// determine (in conjunction with areLoadsFromSameBasePtr) if two loads 156 /// should be scheduled togther. On some targets if two loads are loading from 157 /// addresses in the same cache line, it's better if they are scheduled 158 /// together. This function takes two integers that represent the load offsets 159 /// from the common base address. It returns true if it decides it's desirable 160 /// to schedule the two loads together. "NumLoads" is the number of loads that 161 /// have already been scheduled after Load1. 162 virtual bool shouldScheduleLoadsNear(SDNode *Load1, SDNode *Load2, 163 int64_t Offset1, int64_t Offset2, 164 unsigned NumLoads) const; 165 166 virtual bool isSchedulingBoundary(const MachineInstr *MI, 167 const MachineBasicBlock *MBB, 168 const MachineFunction &MF) const; 169 170 virtual bool isProfitableToIfCvt(MachineBasicBlock &MBB, 171 unsigned NumCycles, unsigned ExtraPredCycles, 172 const BranchProbability &Probability) const; 173 174 virtual bool isProfitableToIfCvt(MachineBasicBlock &TMBB, 175 unsigned NumT, unsigned ExtraT, 176 MachineBasicBlock &FMBB, 177 unsigned NumF, unsigned ExtraF, 178 const BranchProbability &Probability) const; 179 180 virtual bool isProfitableToDupForIfCvt(MachineBasicBlock &MBB, 181 unsigned NumCycles, 182 const BranchProbability 183 &Probability) const { 184 return NumCycles == 1; 185 } 186 187 /// AnalyzeCompare - For a comparison instruction, return the source register 188 /// in SrcReg and the value it compares against in CmpValue. Return true if 189 /// the comparison instruction can be analyzed. 190 virtual bool AnalyzeCompare(const MachineInstr *MI, unsigned &SrcReg, 191 int &CmpMask, int &CmpValue) const; 192 193 /// OptimizeCompareInstr - Convert the instruction to set the zero flag so 194 /// that we can remove a "comparison with zero". 195 virtual bool OptimizeCompareInstr(MachineInstr *CmpInstr, unsigned SrcReg, 196 int CmpMask, int CmpValue, 197 const MachineRegisterInfo *MRI) const; 198 199 /// FoldImmediate - 'Reg' is known to be defined by a move immediate 200 /// instruction, try to fold the immediate into the use instruction. 201 virtual bool FoldImmediate(MachineInstr *UseMI, MachineInstr *DefMI, 202 unsigned Reg, MachineRegisterInfo *MRI) const; 203 204 virtual unsigned getNumMicroOps(const InstrItineraryData *ItinData, 205 const MachineInstr *MI) const; 206 207 virtual 208 int getOperandLatency(const InstrItineraryData *ItinData, 209 const MachineInstr *DefMI, unsigned DefIdx, 210 const MachineInstr *UseMI, unsigned UseIdx) const; 211 virtual 212 int getOperandLatency(const InstrItineraryData *ItinData, 213 SDNode *DefNode, unsigned DefIdx, 214 SDNode *UseNode, unsigned UseIdx) const; 215 216 /// VFP/NEON execution domains. 217 std::pair<uint16_t, uint16_t> 218 getExecutionDomain(const MachineInstr *MI) const; 219 void setExecutionDomain(MachineInstr *MI, unsigned Domain) const; 220 221 private: 222 int getVLDMDefCycle(const InstrItineraryData *ItinData, 223 const MCInstrDesc &DefMCID, 224 unsigned DefClass, 225 unsigned DefIdx, unsigned DefAlign) const; 226 int getLDMDefCycle(const InstrItineraryData *ItinData, 227 const MCInstrDesc &DefMCID, 228 unsigned DefClass, 229 unsigned DefIdx, unsigned DefAlign) const; 230 int getVSTMUseCycle(const InstrItineraryData *ItinData, 231 const MCInstrDesc &UseMCID, 232 unsigned UseClass, 233 unsigned UseIdx, unsigned UseAlign) const; 234 int getSTMUseCycle(const InstrItineraryData *ItinData, 235 const MCInstrDesc &UseMCID, 236 unsigned UseClass, 237 unsigned UseIdx, unsigned UseAlign) const; 238 int getOperandLatency(const InstrItineraryData *ItinData, 239 const MCInstrDesc &DefMCID, 240 unsigned DefIdx, unsigned DefAlign, 241 const MCInstrDesc &UseMCID, 242 unsigned UseIdx, unsigned UseAlign) const; 243 244 int getInstrLatency(const InstrItineraryData *ItinData, 245 const MachineInstr *MI, unsigned *PredCost = 0) const; 246 247 int getInstrLatency(const InstrItineraryData *ItinData, 248 SDNode *Node) const; 249 250 bool hasHighOperandLatency(const InstrItineraryData *ItinData, 251 const MachineRegisterInfo *MRI, 252 const MachineInstr *DefMI, unsigned DefIdx, 253 const MachineInstr *UseMI, unsigned UseIdx) const; 254 bool hasLowDefLatency(const InstrItineraryData *ItinData, 255 const MachineInstr *DefMI, unsigned DefIdx) const; 256 257 /// verifyInstruction - Perform target specific instruction verification. 258 bool verifyInstruction(const MachineInstr *MI, StringRef &ErrInfo) const; 259 260 private: 261 /// Modeling special VFP / NEON fp MLA / MLS hazards. 262 263 /// MLxEntryMap - Map fp MLA / MLS to the corresponding entry in the internal 264 /// MLx table. 265 DenseMap<unsigned, unsigned> MLxEntryMap; 266 267 /// MLxHazardOpcodes - Set of add / sub and multiply opcodes that would cause 268 /// stalls when scheduled together with fp MLA / MLS opcodes. 269 SmallSet<unsigned, 16> MLxHazardOpcodes; 270 271 public: 272 /// isFpMLxInstruction - Return true if the specified opcode is a fp MLA / MLS 273 /// instruction. 274 bool isFpMLxInstruction(unsigned Opcode) const { 275 return MLxEntryMap.count(Opcode); 276 } 277 278 /// isFpMLxInstruction - This version also returns the multiply opcode and the 279 /// addition / subtraction opcode to expand to. Return true for 'HasLane' for 280 /// the MLX instructions with an extra lane operand. 281 bool isFpMLxInstruction(unsigned Opcode, unsigned &MulOpc, 282 unsigned &AddSubOpc, bool &NegAcc, 283 bool &HasLane) const; 284 285 /// canCauseFpMLxStall - Return true if an instruction of the specified opcode 286 /// will cause stalls when scheduled after (within 4-cycle window) a fp 287 /// MLA / MLS instruction. 288 bool canCauseFpMLxStall(unsigned Opcode) const { 289 return MLxHazardOpcodes.count(Opcode); 290 } 291 }; 292 293 static inline 294 const MachineInstrBuilder &AddDefaultPred(const MachineInstrBuilder &MIB) { 295 return MIB.addImm((int64_t)ARMCC::AL).addReg(0); 296 } 297 298 static inline 299 const MachineInstrBuilder &AddDefaultCC(const MachineInstrBuilder &MIB) { 300 return MIB.addReg(0); 301 } 302 303 static inline 304 const MachineInstrBuilder &AddDefaultT1CC(const MachineInstrBuilder &MIB, 305 bool isDead = false) { 306 return MIB.addReg(ARM::CPSR, getDefRegState(true) | getDeadRegState(isDead)); 307 } 308 309 static inline 310 const MachineInstrBuilder &AddNoT1CC(const MachineInstrBuilder &MIB) { 311 return MIB.addReg(0); 312 } 313 314 static inline 315 bool isUncondBranchOpcode(int Opc) { 316 return Opc == ARM::B || Opc == ARM::tB || Opc == ARM::t2B; 317 } 318 319 static inline 320 bool isCondBranchOpcode(int Opc) { 321 return Opc == ARM::Bcc || Opc == ARM::tBcc || Opc == ARM::t2Bcc; 322 } 323 324 static inline 325 bool isJumpTableBranchOpcode(int Opc) { 326 return Opc == ARM::BR_JTr || Opc == ARM::BR_JTm || Opc == ARM::BR_JTadd || 327 Opc == ARM::tBR_JTr || Opc == ARM::t2BR_JT; 328 } 329 330 static inline 331 bool isIndirectBranchOpcode(int Opc) { 332 return Opc == ARM::BX || Opc == ARM::MOVPCRX || Opc == ARM::tBRIND; 333 } 334 335 /// getInstrPredicate - If instruction is predicated, returns its predicate 336 /// condition, otherwise returns AL. It also returns the condition code 337 /// register by reference. 338 ARMCC::CondCodes getInstrPredicate(const MachineInstr *MI, unsigned &PredReg); 339 340 int getMatchingCondBranchOpcode(int Opc); 341 342 343 /// Map pseudo instructions that imply an 'S' bit onto real opcodes. Whether 344 /// the instruction is encoded with an 'S' bit is determined by the optional 345 /// CPSR def operand. 346 unsigned convertAddSubFlagsOpcode(unsigned OldOpc); 347 348 /// emitARMRegPlusImmediate / emitT2RegPlusImmediate - Emits a series of 349 /// instructions to materializea destreg = basereg + immediate in ARM / Thumb2 350 /// code. 351 void emitARMRegPlusImmediate(MachineBasicBlock &MBB, 352 MachineBasicBlock::iterator &MBBI, DebugLoc dl, 353 unsigned DestReg, unsigned BaseReg, int NumBytes, 354 ARMCC::CondCodes Pred, unsigned PredReg, 355 const ARMBaseInstrInfo &TII, unsigned MIFlags = 0); 356 357 void emitT2RegPlusImmediate(MachineBasicBlock &MBB, 358 MachineBasicBlock::iterator &MBBI, DebugLoc dl, 359 unsigned DestReg, unsigned BaseReg, int NumBytes, 360 ARMCC::CondCodes Pred, unsigned PredReg, 361 const ARMBaseInstrInfo &TII, unsigned MIFlags = 0); 362 void emitThumbRegPlusImmediate(MachineBasicBlock &MBB, 363 MachineBasicBlock::iterator &MBBI, DebugLoc dl, 364 unsigned DestReg, unsigned BaseReg, 365 int NumBytes, const TargetInstrInfo &TII, 366 const ARMBaseRegisterInfo& MRI, 367 unsigned MIFlags = 0); 368 369 370 /// rewriteARMFrameIndex / rewriteT2FrameIndex - 371 /// Rewrite MI to access 'Offset' bytes from the FP. Return false if the 372 /// offset could not be handled directly in MI, and return the left-over 373 /// portion by reference. 374 bool rewriteARMFrameIndex(MachineInstr &MI, unsigned FrameRegIdx, 375 unsigned FrameReg, int &Offset, 376 const ARMBaseInstrInfo &TII); 377 378 bool rewriteT2FrameIndex(MachineInstr &MI, unsigned FrameRegIdx, 379 unsigned FrameReg, int &Offset, 380 const ARMBaseInstrInfo &TII); 381 382 } // End llvm namespace 383 384 #endif 385