1 //===-- ARMBaseInstrInfo.cpp - ARM Instruction Information ----------------===// 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 #include "ARM.h" 15 #include "ARMBaseInstrInfo.h" 16 #include "ARMBaseRegisterInfo.h" 17 #include "ARMConstantPoolValue.h" 18 #include "ARMFeatures.h" 19 #include "ARMHazardRecognizer.h" 20 #include "ARMMachineFunctionInfo.h" 21 #include "MCTargetDesc/ARMAddressingModes.h" 22 #include "llvm/ADT/STLExtras.h" 23 #include "llvm/CodeGen/LiveVariables.h" 24 #include "llvm/CodeGen/MachineConstantPool.h" 25 #include "llvm/CodeGen/MachineFrameInfo.h" 26 #include "llvm/CodeGen/MachineInstrBuilder.h" 27 #include "llvm/CodeGen/MachineJumpTableInfo.h" 28 #include "llvm/CodeGen/MachineMemOperand.h" 29 #include "llvm/CodeGen/MachineRegisterInfo.h" 30 #include "llvm/CodeGen/SelectionDAGNodes.h" 31 #include "llvm/CodeGen/TargetSchedule.h" 32 #include "llvm/IR/Constants.h" 33 #include "llvm/IR/Function.h" 34 #include "llvm/IR/GlobalValue.h" 35 #include "llvm/MC/MCAsmInfo.h" 36 #include "llvm/MC/MCExpr.h" 37 #include "llvm/Support/BranchProbability.h" 38 #include "llvm/Support/CommandLine.h" 39 #include "llvm/Support/Debug.h" 40 #include "llvm/Support/ErrorHandling.h" 41 #include "llvm/Support/raw_ostream.h" 42 43 using namespace llvm; 44 45 #define DEBUG_TYPE "arm-instrinfo" 46 47 #define GET_INSTRINFO_CTOR_DTOR 48 #include "ARMGenInstrInfo.inc" 49 50 static cl::opt<bool> 51 EnableARM3Addr("enable-arm-3-addr-conv", cl::Hidden, 52 cl::desc("Enable ARM 2-addr to 3-addr conv")); 53 54 /// ARM_MLxEntry - Record information about MLA / MLS instructions. 55 struct ARM_MLxEntry { 56 uint16_t MLxOpc; // MLA / MLS opcode 57 uint16_t MulOpc; // Expanded multiplication opcode 58 uint16_t AddSubOpc; // Expanded add / sub opcode 59 bool NegAcc; // True if the acc is negated before the add / sub. 60 bool HasLane; // True if instruction has an extra "lane" operand. 61 }; 62 63 static const ARM_MLxEntry ARM_MLxTable[] = { 64 // MLxOpc, MulOpc, AddSubOpc, NegAcc, HasLane 65 // fp scalar ops 66 { ARM::VMLAS, ARM::VMULS, ARM::VADDS, false, false }, 67 { ARM::VMLSS, ARM::VMULS, ARM::VSUBS, false, false }, 68 { ARM::VMLAD, ARM::VMULD, ARM::VADDD, false, false }, 69 { ARM::VMLSD, ARM::VMULD, ARM::VSUBD, false, false }, 70 { ARM::VNMLAS, ARM::VNMULS, ARM::VSUBS, true, false }, 71 { ARM::VNMLSS, ARM::VMULS, ARM::VSUBS, true, false }, 72 { ARM::VNMLAD, ARM::VNMULD, ARM::VSUBD, true, false }, 73 { ARM::VNMLSD, ARM::VMULD, ARM::VSUBD, true, false }, 74 75 // fp SIMD ops 76 { ARM::VMLAfd, ARM::VMULfd, ARM::VADDfd, false, false }, 77 { ARM::VMLSfd, ARM::VMULfd, ARM::VSUBfd, false, false }, 78 { ARM::VMLAfq, ARM::VMULfq, ARM::VADDfq, false, false }, 79 { ARM::VMLSfq, ARM::VMULfq, ARM::VSUBfq, false, false }, 80 { ARM::VMLAslfd, ARM::VMULslfd, ARM::VADDfd, false, true }, 81 { ARM::VMLSslfd, ARM::VMULslfd, ARM::VSUBfd, false, true }, 82 { ARM::VMLAslfq, ARM::VMULslfq, ARM::VADDfq, false, true }, 83 { ARM::VMLSslfq, ARM::VMULslfq, ARM::VSUBfq, false, true }, 84 }; 85 86 ARMBaseInstrInfo::ARMBaseInstrInfo(const ARMSubtarget& STI) 87 : ARMGenInstrInfo(ARM::ADJCALLSTACKDOWN, ARM::ADJCALLSTACKUP), 88 Subtarget(STI) { 89 for (unsigned i = 0, e = array_lengthof(ARM_MLxTable); i != e; ++i) { 90 if (!MLxEntryMap.insert(std::make_pair(ARM_MLxTable[i].MLxOpc, i)).second) 91 llvm_unreachable("Duplicated entries?"); 92 MLxHazardOpcodes.insert(ARM_MLxTable[i].AddSubOpc); 93 MLxHazardOpcodes.insert(ARM_MLxTable[i].MulOpc); 94 } 95 } 96 97 // Use a ScoreboardHazardRecognizer for prepass ARM scheduling. TargetInstrImpl 98 // currently defaults to no prepass hazard recognizer. 99 ScheduleHazardRecognizer * 100 ARMBaseInstrInfo::CreateTargetHazardRecognizer(const TargetSubtargetInfo *STI, 101 const ScheduleDAG *DAG) const { 102 if (usePreRAHazardRecognizer()) { 103 const InstrItineraryData *II = 104 static_cast<const ARMSubtarget *>(STI)->getInstrItineraryData(); 105 return new ScoreboardHazardRecognizer(II, DAG, "pre-RA-sched"); 106 } 107 return TargetInstrInfo::CreateTargetHazardRecognizer(STI, DAG); 108 } 109 110 ScheduleHazardRecognizer *ARMBaseInstrInfo:: 111 CreateTargetPostRAHazardRecognizer(const InstrItineraryData *II, 112 const ScheduleDAG *DAG) const { 113 if (Subtarget.isThumb2() || Subtarget.hasVFP2()) 114 return (ScheduleHazardRecognizer *)new ARMHazardRecognizer(II, DAG); 115 return TargetInstrInfo::CreateTargetPostRAHazardRecognizer(II, DAG); 116 } 117 118 MachineInstr *ARMBaseInstrInfo::convertToThreeAddress( 119 MachineFunction::iterator &MFI, MachineInstr &MI, LiveVariables *LV) const { 120 // FIXME: Thumb2 support. 121 122 if (!EnableARM3Addr) 123 return nullptr; 124 125 MachineFunction &MF = *MI.getParent()->getParent(); 126 uint64_t TSFlags = MI.getDesc().TSFlags; 127 bool isPre = false; 128 switch ((TSFlags & ARMII::IndexModeMask) >> ARMII::IndexModeShift) { 129 default: return nullptr; 130 case ARMII::IndexModePre: 131 isPre = true; 132 break; 133 case ARMII::IndexModePost: 134 break; 135 } 136 137 // Try splitting an indexed load/store to an un-indexed one plus an add/sub 138 // operation. 139 unsigned MemOpc = getUnindexedOpcode(MI.getOpcode()); 140 if (MemOpc == 0) 141 return nullptr; 142 143 MachineInstr *UpdateMI = nullptr; 144 MachineInstr *MemMI = nullptr; 145 unsigned AddrMode = (TSFlags & ARMII::AddrModeMask); 146 const MCInstrDesc &MCID = MI.getDesc(); 147 unsigned NumOps = MCID.getNumOperands(); 148 bool isLoad = !MI.mayStore(); 149 const MachineOperand &WB = isLoad ? MI.getOperand(1) : MI.getOperand(0); 150 const MachineOperand &Base = MI.getOperand(2); 151 const MachineOperand &Offset = MI.getOperand(NumOps - 3); 152 unsigned WBReg = WB.getReg(); 153 unsigned BaseReg = Base.getReg(); 154 unsigned OffReg = Offset.getReg(); 155 unsigned OffImm = MI.getOperand(NumOps - 2).getImm(); 156 ARMCC::CondCodes Pred = (ARMCC::CondCodes)MI.getOperand(NumOps - 1).getImm(); 157 switch (AddrMode) { 158 default: llvm_unreachable("Unknown indexed op!"); 159 case ARMII::AddrMode2: { 160 bool isSub = ARM_AM::getAM2Op(OffImm) == ARM_AM::sub; 161 unsigned Amt = ARM_AM::getAM2Offset(OffImm); 162 if (OffReg == 0) { 163 if (ARM_AM::getSOImmVal(Amt) == -1) 164 // Can't encode it in a so_imm operand. This transformation will 165 // add more than 1 instruction. Abandon! 166 return nullptr; 167 UpdateMI = BuildMI(MF, MI.getDebugLoc(), 168 get(isSub ? ARM::SUBri : ARM::ADDri), WBReg) 169 .addReg(BaseReg) 170 .addImm(Amt) 171 .addImm(Pred) 172 .addReg(0) 173 .addReg(0); 174 } else if (Amt != 0) { 175 ARM_AM::ShiftOpc ShOpc = ARM_AM::getAM2ShiftOpc(OffImm); 176 unsigned SOOpc = ARM_AM::getSORegOpc(ShOpc, Amt); 177 UpdateMI = BuildMI(MF, MI.getDebugLoc(), 178 get(isSub ? ARM::SUBrsi : ARM::ADDrsi), WBReg) 179 .addReg(BaseReg) 180 .addReg(OffReg) 181 .addReg(0) 182 .addImm(SOOpc) 183 .addImm(Pred) 184 .addReg(0) 185 .addReg(0); 186 } else 187 UpdateMI = BuildMI(MF, MI.getDebugLoc(), 188 get(isSub ? ARM::SUBrr : ARM::ADDrr), WBReg) 189 .addReg(BaseReg) 190 .addReg(OffReg) 191 .addImm(Pred) 192 .addReg(0) 193 .addReg(0); 194 break; 195 } 196 case ARMII::AddrMode3 : { 197 bool isSub = ARM_AM::getAM3Op(OffImm) == ARM_AM::sub; 198 unsigned Amt = ARM_AM::getAM3Offset(OffImm); 199 if (OffReg == 0) 200 // Immediate is 8-bits. It's guaranteed to fit in a so_imm operand. 201 UpdateMI = BuildMI(MF, MI.getDebugLoc(), 202 get(isSub ? ARM::SUBri : ARM::ADDri), WBReg) 203 .addReg(BaseReg) 204 .addImm(Amt) 205 .addImm(Pred) 206 .addReg(0) 207 .addReg(0); 208 else 209 UpdateMI = BuildMI(MF, MI.getDebugLoc(), 210 get(isSub ? ARM::SUBrr : ARM::ADDrr), WBReg) 211 .addReg(BaseReg) 212 .addReg(OffReg) 213 .addImm(Pred) 214 .addReg(0) 215 .addReg(0); 216 break; 217 } 218 } 219 220 std::vector<MachineInstr*> NewMIs; 221 if (isPre) { 222 if (isLoad) 223 MemMI = 224 BuildMI(MF, MI.getDebugLoc(), get(MemOpc), MI.getOperand(0).getReg()) 225 .addReg(WBReg) 226 .addImm(0) 227 .addImm(Pred); 228 else 229 MemMI = BuildMI(MF, MI.getDebugLoc(), get(MemOpc)) 230 .addReg(MI.getOperand(1).getReg()) 231 .addReg(WBReg) 232 .addReg(0) 233 .addImm(0) 234 .addImm(Pred); 235 NewMIs.push_back(MemMI); 236 NewMIs.push_back(UpdateMI); 237 } else { 238 if (isLoad) 239 MemMI = 240 BuildMI(MF, MI.getDebugLoc(), get(MemOpc), MI.getOperand(0).getReg()) 241 .addReg(BaseReg) 242 .addImm(0) 243 .addImm(Pred); 244 else 245 MemMI = BuildMI(MF, MI.getDebugLoc(), get(MemOpc)) 246 .addReg(MI.getOperand(1).getReg()) 247 .addReg(BaseReg) 248 .addReg(0) 249 .addImm(0) 250 .addImm(Pred); 251 if (WB.isDead()) 252 UpdateMI->getOperand(0).setIsDead(); 253 NewMIs.push_back(UpdateMI); 254 NewMIs.push_back(MemMI); 255 } 256 257 // Transfer LiveVariables states, kill / dead info. 258 if (LV) { 259 for (unsigned i = 0, e = MI.getNumOperands(); i != e; ++i) { 260 MachineOperand &MO = MI.getOperand(i); 261 if (MO.isReg() && TargetRegisterInfo::isVirtualRegister(MO.getReg())) { 262 unsigned Reg = MO.getReg(); 263 264 LiveVariables::VarInfo &VI = LV->getVarInfo(Reg); 265 if (MO.isDef()) { 266 MachineInstr *NewMI = (Reg == WBReg) ? UpdateMI : MemMI; 267 if (MO.isDead()) 268 LV->addVirtualRegisterDead(Reg, *NewMI); 269 } 270 if (MO.isUse() && MO.isKill()) { 271 for (unsigned j = 0; j < 2; ++j) { 272 // Look at the two new MI's in reverse order. 273 MachineInstr *NewMI = NewMIs[j]; 274 if (!NewMI->readsRegister(Reg)) 275 continue; 276 LV->addVirtualRegisterKilled(Reg, *NewMI); 277 if (VI.removeKill(MI)) 278 VI.Kills.push_back(NewMI); 279 break; 280 } 281 } 282 } 283 } 284 } 285 286 MachineBasicBlock::iterator MBBI = MI.getIterator(); 287 MFI->insert(MBBI, NewMIs[1]); 288 MFI->insert(MBBI, NewMIs[0]); 289 return NewMIs[0]; 290 } 291 292 // Branch analysis. 293 bool ARMBaseInstrInfo::analyzeBranch(MachineBasicBlock &MBB, 294 MachineBasicBlock *&TBB, 295 MachineBasicBlock *&FBB, 296 SmallVectorImpl<MachineOperand> &Cond, 297 bool AllowModify) const { 298 TBB = nullptr; 299 FBB = nullptr; 300 301 MachineBasicBlock::iterator I = MBB.end(); 302 if (I == MBB.begin()) 303 return false; // Empty blocks are easy. 304 --I; 305 306 // Walk backwards from the end of the basic block until the branch is 307 // analyzed or we give up. 308 while (isPredicated(*I) || I->isTerminator() || I->isDebugValue()) { 309 310 // Flag to be raised on unanalyzeable instructions. This is useful in cases 311 // where we want to clean up on the end of the basic block before we bail 312 // out. 313 bool CantAnalyze = false; 314 315 // Skip over DEBUG values and predicated nonterminators. 316 while (I->isDebugValue() || !I->isTerminator()) { 317 if (I == MBB.begin()) 318 return false; 319 --I; 320 } 321 322 if (isIndirectBranchOpcode(I->getOpcode()) || 323 isJumpTableBranchOpcode(I->getOpcode())) { 324 // Indirect branches and jump tables can't be analyzed, but we still want 325 // to clean up any instructions at the tail of the basic block. 326 CantAnalyze = true; 327 } else if (isUncondBranchOpcode(I->getOpcode())) { 328 TBB = I->getOperand(0).getMBB(); 329 } else if (isCondBranchOpcode(I->getOpcode())) { 330 // Bail out if we encounter multiple conditional branches. 331 if (!Cond.empty()) 332 return true; 333 334 assert(!FBB && "FBB should have been null."); 335 FBB = TBB; 336 TBB = I->getOperand(0).getMBB(); 337 Cond.push_back(I->getOperand(1)); 338 Cond.push_back(I->getOperand(2)); 339 } else if (I->isReturn()) { 340 // Returns can't be analyzed, but we should run cleanup. 341 CantAnalyze = !isPredicated(*I); 342 } else { 343 // We encountered other unrecognized terminator. Bail out immediately. 344 return true; 345 } 346 347 // Cleanup code - to be run for unpredicated unconditional branches and 348 // returns. 349 if (!isPredicated(*I) && 350 (isUncondBranchOpcode(I->getOpcode()) || 351 isIndirectBranchOpcode(I->getOpcode()) || 352 isJumpTableBranchOpcode(I->getOpcode()) || 353 I->isReturn())) { 354 // Forget any previous condition branch information - it no longer applies. 355 Cond.clear(); 356 FBB = nullptr; 357 358 // If we can modify the function, delete everything below this 359 // unconditional branch. 360 if (AllowModify) { 361 MachineBasicBlock::iterator DI = std::next(I); 362 while (DI != MBB.end()) { 363 MachineInstr &InstToDelete = *DI; 364 ++DI; 365 InstToDelete.eraseFromParent(); 366 } 367 } 368 } 369 370 if (CantAnalyze) 371 return true; 372 373 if (I == MBB.begin()) 374 return false; 375 376 --I; 377 } 378 379 // We made it past the terminators without bailing out - we must have 380 // analyzed this branch successfully. 381 return false; 382 } 383 384 385 unsigned ARMBaseInstrInfo::removeBranch(MachineBasicBlock &MBB, 386 int *BytesRemoved) const { 387 assert(!BytesRemoved && "code size not handled"); 388 389 MachineBasicBlock::iterator I = MBB.getLastNonDebugInstr(); 390 if (I == MBB.end()) 391 return 0; 392 393 if (!isUncondBranchOpcode(I->getOpcode()) && 394 !isCondBranchOpcode(I->getOpcode())) 395 return 0; 396 397 // Remove the branch. 398 I->eraseFromParent(); 399 400 I = MBB.end(); 401 402 if (I == MBB.begin()) return 1; 403 --I; 404 if (!isCondBranchOpcode(I->getOpcode())) 405 return 1; 406 407 // Remove the branch. 408 I->eraseFromParent(); 409 return 2; 410 } 411 412 unsigned ARMBaseInstrInfo::insertBranch(MachineBasicBlock &MBB, 413 MachineBasicBlock *TBB, 414 MachineBasicBlock *FBB, 415 ArrayRef<MachineOperand> Cond, 416 const DebugLoc &DL, 417 int *BytesAdded) const { 418 assert(!BytesAdded && "code size not handled"); 419 ARMFunctionInfo *AFI = MBB.getParent()->getInfo<ARMFunctionInfo>(); 420 int BOpc = !AFI->isThumbFunction() 421 ? ARM::B : (AFI->isThumb2Function() ? ARM::t2B : ARM::tB); 422 int BccOpc = !AFI->isThumbFunction() 423 ? ARM::Bcc : (AFI->isThumb2Function() ? ARM::t2Bcc : ARM::tBcc); 424 bool isThumb = AFI->isThumbFunction() || AFI->isThumb2Function(); 425 426 // Shouldn't be a fall through. 427 assert(TBB && "insertBranch must not be told to insert a fallthrough"); 428 assert((Cond.size() == 2 || Cond.size() == 0) && 429 "ARM branch conditions have two components!"); 430 431 // For conditional branches, we use addOperand to preserve CPSR flags. 432 433 if (!FBB) { 434 if (Cond.empty()) { // Unconditional branch? 435 if (isThumb) 436 BuildMI(&MBB, DL, get(BOpc)).addMBB(TBB).addImm(ARMCC::AL).addReg(0); 437 else 438 BuildMI(&MBB, DL, get(BOpc)).addMBB(TBB); 439 } else 440 BuildMI(&MBB, DL, get(BccOpc)).addMBB(TBB) 441 .addImm(Cond[0].getImm()).addOperand(Cond[1]); 442 return 1; 443 } 444 445 // Two-way conditional branch. 446 BuildMI(&MBB, DL, get(BccOpc)).addMBB(TBB) 447 .addImm(Cond[0].getImm()).addOperand(Cond[1]); 448 if (isThumb) 449 BuildMI(&MBB, DL, get(BOpc)).addMBB(FBB).addImm(ARMCC::AL).addReg(0); 450 else 451 BuildMI(&MBB, DL, get(BOpc)).addMBB(FBB); 452 return 2; 453 } 454 455 bool ARMBaseInstrInfo:: 456 reverseBranchCondition(SmallVectorImpl<MachineOperand> &Cond) const { 457 ARMCC::CondCodes CC = (ARMCC::CondCodes)(int)Cond[0].getImm(); 458 Cond[0].setImm(ARMCC::getOppositeCondition(CC)); 459 return false; 460 } 461 462 bool ARMBaseInstrInfo::isPredicated(const MachineInstr &MI) const { 463 if (MI.isBundle()) { 464 MachineBasicBlock::const_instr_iterator I = MI.getIterator(); 465 MachineBasicBlock::const_instr_iterator E = MI.getParent()->instr_end(); 466 while (++I != E && I->isInsideBundle()) { 467 int PIdx = I->findFirstPredOperandIdx(); 468 if (PIdx != -1 && I->getOperand(PIdx).getImm() != ARMCC::AL) 469 return true; 470 } 471 return false; 472 } 473 474 int PIdx = MI.findFirstPredOperandIdx(); 475 return PIdx != -1 && MI.getOperand(PIdx).getImm() != ARMCC::AL; 476 } 477 478 bool ARMBaseInstrInfo::PredicateInstruction( 479 MachineInstr &MI, ArrayRef<MachineOperand> Pred) const { 480 unsigned Opc = MI.getOpcode(); 481 if (isUncondBranchOpcode(Opc)) { 482 MI.setDesc(get(getMatchingCondBranchOpcode(Opc))); 483 MachineInstrBuilder(*MI.getParent()->getParent(), MI) 484 .addImm(Pred[0].getImm()) 485 .addReg(Pred[1].getReg()); 486 return true; 487 } 488 489 int PIdx = MI.findFirstPredOperandIdx(); 490 if (PIdx != -1) { 491 MachineOperand &PMO = MI.getOperand(PIdx); 492 PMO.setImm(Pred[0].getImm()); 493 MI.getOperand(PIdx+1).setReg(Pred[1].getReg()); 494 return true; 495 } 496 return false; 497 } 498 499 bool ARMBaseInstrInfo::SubsumesPredicate(ArrayRef<MachineOperand> Pred1, 500 ArrayRef<MachineOperand> Pred2) const { 501 if (Pred1.size() > 2 || Pred2.size() > 2) 502 return false; 503 504 ARMCC::CondCodes CC1 = (ARMCC::CondCodes)Pred1[0].getImm(); 505 ARMCC::CondCodes CC2 = (ARMCC::CondCodes)Pred2[0].getImm(); 506 if (CC1 == CC2) 507 return true; 508 509 switch (CC1) { 510 default: 511 return false; 512 case ARMCC::AL: 513 return true; 514 case ARMCC::HS: 515 return CC2 == ARMCC::HI; 516 case ARMCC::LS: 517 return CC2 == ARMCC::LO || CC2 == ARMCC::EQ; 518 case ARMCC::GE: 519 return CC2 == ARMCC::GT; 520 case ARMCC::LE: 521 return CC2 == ARMCC::LT; 522 } 523 } 524 525 bool ARMBaseInstrInfo::DefinesPredicate( 526 MachineInstr &MI, std::vector<MachineOperand> &Pred) const { 527 bool Found = false; 528 for (unsigned i = 0, e = MI.getNumOperands(); i != e; ++i) { 529 const MachineOperand &MO = MI.getOperand(i); 530 if ((MO.isRegMask() && MO.clobbersPhysReg(ARM::CPSR)) || 531 (MO.isReg() && MO.isDef() && MO.getReg() == ARM::CPSR)) { 532 Pred.push_back(MO); 533 Found = true; 534 } 535 } 536 537 return Found; 538 } 539 540 static bool isCPSRDefined(const MachineInstr *MI) { 541 for (const auto &MO : MI->operands()) 542 if (MO.isReg() && MO.getReg() == ARM::CPSR && MO.isDef() && !MO.isDead()) 543 return true; 544 return false; 545 } 546 547 static bool isEligibleForITBlock(const MachineInstr *MI) { 548 switch (MI->getOpcode()) { 549 default: return true; 550 case ARM::tADC: // ADC (register) T1 551 case ARM::tADDi3: // ADD (immediate) T1 552 case ARM::tADDi8: // ADD (immediate) T2 553 case ARM::tADDrr: // ADD (register) T1 554 case ARM::tAND: // AND (register) T1 555 case ARM::tASRri: // ASR (immediate) T1 556 case ARM::tASRrr: // ASR (register) T1 557 case ARM::tBIC: // BIC (register) T1 558 case ARM::tEOR: // EOR (register) T1 559 case ARM::tLSLri: // LSL (immediate) T1 560 case ARM::tLSLrr: // LSL (register) T1 561 case ARM::tLSRri: // LSR (immediate) T1 562 case ARM::tLSRrr: // LSR (register) T1 563 case ARM::tMUL: // MUL T1 564 case ARM::tMVN: // MVN (register) T1 565 case ARM::tORR: // ORR (register) T1 566 case ARM::tROR: // ROR (register) T1 567 case ARM::tRSB: // RSB (immediate) T1 568 case ARM::tSBC: // SBC (register) T1 569 case ARM::tSUBi3: // SUB (immediate) T1 570 case ARM::tSUBi8: // SUB (immediate) T2 571 case ARM::tSUBrr: // SUB (register) T1 572 return !isCPSRDefined(MI); 573 } 574 } 575 576 /// isPredicable - Return true if the specified instruction can be predicated. 577 /// By default, this returns true for every instruction with a 578 /// PredicateOperand. 579 bool ARMBaseInstrInfo::isPredicable(MachineInstr &MI) const { 580 if (!MI.isPredicable()) 581 return false; 582 583 if (MI.isBundle()) 584 return false; 585 586 if (!isEligibleForITBlock(&MI)) 587 return false; 588 589 ARMFunctionInfo *AFI = 590 MI.getParent()->getParent()->getInfo<ARMFunctionInfo>(); 591 592 if (AFI->isThumb2Function()) { 593 if (getSubtarget().restrictIT()) 594 return isV8EligibleForIT(&MI); 595 } else { // non-Thumb 596 if ((MI.getDesc().TSFlags & ARMII::DomainMask) == ARMII::DomainNEON) 597 return false; 598 } 599 600 return true; 601 } 602 603 namespace llvm { 604 template <> bool IsCPSRDead<MachineInstr>(MachineInstr *MI) { 605 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) { 606 const MachineOperand &MO = MI->getOperand(i); 607 if (!MO.isReg() || MO.isUndef() || MO.isUse()) 608 continue; 609 if (MO.getReg() != ARM::CPSR) 610 continue; 611 if (!MO.isDead()) 612 return false; 613 } 614 // all definitions of CPSR are dead 615 return true; 616 } 617 } 618 619 /// GetInstSize - Return the size of the specified MachineInstr. 620 /// 621 unsigned ARMBaseInstrInfo::getInstSizeInBytes(const MachineInstr &MI) const { 622 const MachineBasicBlock &MBB = *MI.getParent(); 623 const MachineFunction *MF = MBB.getParent(); 624 const MCAsmInfo *MAI = MF->getTarget().getMCAsmInfo(); 625 626 const MCInstrDesc &MCID = MI.getDesc(); 627 if (MCID.getSize()) 628 return MCID.getSize(); 629 630 // If this machine instr is an inline asm, measure it. 631 if (MI.getOpcode() == ARM::INLINEASM) 632 return getInlineAsmLength(MI.getOperand(0).getSymbolName(), *MAI); 633 unsigned Opc = MI.getOpcode(); 634 switch (Opc) { 635 default: 636 // pseudo-instruction sizes are zero. 637 return 0; 638 case TargetOpcode::BUNDLE: 639 return getInstBundleLength(MI); 640 case ARM::MOVi16_ga_pcrel: 641 case ARM::MOVTi16_ga_pcrel: 642 case ARM::t2MOVi16_ga_pcrel: 643 case ARM::t2MOVTi16_ga_pcrel: 644 return 4; 645 case ARM::MOVi32imm: 646 case ARM::t2MOVi32imm: 647 return 8; 648 case ARM::CONSTPOOL_ENTRY: 649 case ARM::JUMPTABLE_INSTS: 650 case ARM::JUMPTABLE_ADDRS: 651 case ARM::JUMPTABLE_TBB: 652 case ARM::JUMPTABLE_TBH: 653 // If this machine instr is a constant pool entry, its size is recorded as 654 // operand #2. 655 return MI.getOperand(2).getImm(); 656 case ARM::Int_eh_sjlj_longjmp: 657 return 16; 658 case ARM::tInt_eh_sjlj_longjmp: 659 return 10; 660 case ARM::tInt_WIN_eh_sjlj_longjmp: 661 return 12; 662 case ARM::Int_eh_sjlj_setjmp: 663 case ARM::Int_eh_sjlj_setjmp_nofp: 664 return 20; 665 case ARM::tInt_eh_sjlj_setjmp: 666 case ARM::t2Int_eh_sjlj_setjmp: 667 case ARM::t2Int_eh_sjlj_setjmp_nofp: 668 return 12; 669 case ARM::SPACE: 670 return MI.getOperand(1).getImm(); 671 } 672 } 673 674 unsigned ARMBaseInstrInfo::getInstBundleLength(const MachineInstr &MI) const { 675 unsigned Size = 0; 676 MachineBasicBlock::const_instr_iterator I = MI.getIterator(); 677 MachineBasicBlock::const_instr_iterator E = MI.getParent()->instr_end(); 678 while (++I != E && I->isInsideBundle()) { 679 assert(!I->isBundle() && "No nested bundle!"); 680 Size += getInstSizeInBytes(*I); 681 } 682 return Size; 683 } 684 685 void ARMBaseInstrInfo::copyFromCPSR(MachineBasicBlock &MBB, 686 MachineBasicBlock::iterator I, 687 unsigned DestReg, bool KillSrc, 688 const ARMSubtarget &Subtarget) const { 689 unsigned Opc = Subtarget.isThumb() 690 ? (Subtarget.isMClass() ? ARM::t2MRS_M : ARM::t2MRS_AR) 691 : ARM::MRS; 692 693 MachineInstrBuilder MIB = 694 BuildMI(MBB, I, I->getDebugLoc(), get(Opc), DestReg); 695 696 // There is only 1 A/R class MRS instruction, and it always refers to 697 // APSR. However, there are lots of other possibilities on M-class cores. 698 if (Subtarget.isMClass()) 699 MIB.addImm(0x800); 700 701 AddDefaultPred(MIB); 702 703 MIB.addReg(ARM::CPSR, RegState::Implicit | getKillRegState(KillSrc)); 704 } 705 706 void ARMBaseInstrInfo::copyToCPSR(MachineBasicBlock &MBB, 707 MachineBasicBlock::iterator I, 708 unsigned SrcReg, bool KillSrc, 709 const ARMSubtarget &Subtarget) const { 710 unsigned Opc = Subtarget.isThumb() 711 ? (Subtarget.isMClass() ? ARM::t2MSR_M : ARM::t2MSR_AR) 712 : ARM::MSR; 713 714 MachineInstrBuilder MIB = BuildMI(MBB, I, I->getDebugLoc(), get(Opc)); 715 716 if (Subtarget.isMClass()) 717 MIB.addImm(0x800); 718 else 719 MIB.addImm(8); 720 721 MIB.addReg(SrcReg, getKillRegState(KillSrc)); 722 723 AddDefaultPred(MIB); 724 725 MIB.addReg(ARM::CPSR, RegState::Implicit | RegState::Define); 726 } 727 728 void ARMBaseInstrInfo::copyPhysReg(MachineBasicBlock &MBB, 729 MachineBasicBlock::iterator I, 730 const DebugLoc &DL, unsigned DestReg, 731 unsigned SrcReg, bool KillSrc) const { 732 bool GPRDest = ARM::GPRRegClass.contains(DestReg); 733 bool GPRSrc = ARM::GPRRegClass.contains(SrcReg); 734 735 if (GPRDest && GPRSrc) { 736 AddDefaultCC(AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::MOVr), DestReg) 737 .addReg(SrcReg, getKillRegState(KillSrc)))); 738 return; 739 } 740 741 bool SPRDest = ARM::SPRRegClass.contains(DestReg); 742 bool SPRSrc = ARM::SPRRegClass.contains(SrcReg); 743 744 unsigned Opc = 0; 745 if (SPRDest && SPRSrc) 746 Opc = ARM::VMOVS; 747 else if (GPRDest && SPRSrc) 748 Opc = ARM::VMOVRS; 749 else if (SPRDest && GPRSrc) 750 Opc = ARM::VMOVSR; 751 else if (ARM::DPRRegClass.contains(DestReg, SrcReg) && !Subtarget.isFPOnlySP()) 752 Opc = ARM::VMOVD; 753 else if (ARM::QPRRegClass.contains(DestReg, SrcReg)) 754 Opc = ARM::VORRq; 755 756 if (Opc) { 757 MachineInstrBuilder MIB = BuildMI(MBB, I, DL, get(Opc), DestReg); 758 MIB.addReg(SrcReg, getKillRegState(KillSrc)); 759 if (Opc == ARM::VORRq) 760 MIB.addReg(SrcReg, getKillRegState(KillSrc)); 761 AddDefaultPred(MIB); 762 return; 763 } 764 765 // Handle register classes that require multiple instructions. 766 unsigned BeginIdx = 0; 767 unsigned SubRegs = 0; 768 int Spacing = 1; 769 770 // Use VORRq when possible. 771 if (ARM::QQPRRegClass.contains(DestReg, SrcReg)) { 772 Opc = ARM::VORRq; 773 BeginIdx = ARM::qsub_0; 774 SubRegs = 2; 775 } else if (ARM::QQQQPRRegClass.contains(DestReg, SrcReg)) { 776 Opc = ARM::VORRq; 777 BeginIdx = ARM::qsub_0; 778 SubRegs = 4; 779 // Fall back to VMOVD. 780 } else if (ARM::DPairRegClass.contains(DestReg, SrcReg)) { 781 Opc = ARM::VMOVD; 782 BeginIdx = ARM::dsub_0; 783 SubRegs = 2; 784 } else if (ARM::DTripleRegClass.contains(DestReg, SrcReg)) { 785 Opc = ARM::VMOVD; 786 BeginIdx = ARM::dsub_0; 787 SubRegs = 3; 788 } else if (ARM::DQuadRegClass.contains(DestReg, SrcReg)) { 789 Opc = ARM::VMOVD; 790 BeginIdx = ARM::dsub_0; 791 SubRegs = 4; 792 } else if (ARM::GPRPairRegClass.contains(DestReg, SrcReg)) { 793 Opc = Subtarget.isThumb2() ? ARM::tMOVr : ARM::MOVr; 794 BeginIdx = ARM::gsub_0; 795 SubRegs = 2; 796 } else if (ARM::DPairSpcRegClass.contains(DestReg, SrcReg)) { 797 Opc = ARM::VMOVD; 798 BeginIdx = ARM::dsub_0; 799 SubRegs = 2; 800 Spacing = 2; 801 } else if (ARM::DTripleSpcRegClass.contains(DestReg, SrcReg)) { 802 Opc = ARM::VMOVD; 803 BeginIdx = ARM::dsub_0; 804 SubRegs = 3; 805 Spacing = 2; 806 } else if (ARM::DQuadSpcRegClass.contains(DestReg, SrcReg)) { 807 Opc = ARM::VMOVD; 808 BeginIdx = ARM::dsub_0; 809 SubRegs = 4; 810 Spacing = 2; 811 } else if (ARM::DPRRegClass.contains(DestReg, SrcReg) && Subtarget.isFPOnlySP()) { 812 Opc = ARM::VMOVS; 813 BeginIdx = ARM::ssub_0; 814 SubRegs = 2; 815 } else if (SrcReg == ARM::CPSR) { 816 copyFromCPSR(MBB, I, DestReg, KillSrc, Subtarget); 817 return; 818 } else if (DestReg == ARM::CPSR) { 819 copyToCPSR(MBB, I, SrcReg, KillSrc, Subtarget); 820 return; 821 } 822 823 assert(Opc && "Impossible reg-to-reg copy"); 824 825 const TargetRegisterInfo *TRI = &getRegisterInfo(); 826 MachineInstrBuilder Mov; 827 828 // Copy register tuples backward when the first Dest reg overlaps with SrcReg. 829 if (TRI->regsOverlap(SrcReg, TRI->getSubReg(DestReg, BeginIdx))) { 830 BeginIdx = BeginIdx + ((SubRegs - 1) * Spacing); 831 Spacing = -Spacing; 832 } 833 #ifndef NDEBUG 834 SmallSet<unsigned, 4> DstRegs; 835 #endif 836 for (unsigned i = 0; i != SubRegs; ++i) { 837 unsigned Dst = TRI->getSubReg(DestReg, BeginIdx + i * Spacing); 838 unsigned Src = TRI->getSubReg(SrcReg, BeginIdx + i * Spacing); 839 assert(Dst && Src && "Bad sub-register"); 840 #ifndef NDEBUG 841 assert(!DstRegs.count(Src) && "destructive vector copy"); 842 DstRegs.insert(Dst); 843 #endif 844 Mov = BuildMI(MBB, I, I->getDebugLoc(), get(Opc), Dst).addReg(Src); 845 // VORR takes two source operands. 846 if (Opc == ARM::VORRq) 847 Mov.addReg(Src); 848 Mov = AddDefaultPred(Mov); 849 // MOVr can set CC. 850 if (Opc == ARM::MOVr) 851 Mov = AddDefaultCC(Mov); 852 } 853 // Add implicit super-register defs and kills to the last instruction. 854 Mov->addRegisterDefined(DestReg, TRI); 855 if (KillSrc) 856 Mov->addRegisterKilled(SrcReg, TRI); 857 } 858 859 const MachineInstrBuilder & 860 ARMBaseInstrInfo::AddDReg(MachineInstrBuilder &MIB, unsigned Reg, 861 unsigned SubIdx, unsigned State, 862 const TargetRegisterInfo *TRI) const { 863 if (!SubIdx) 864 return MIB.addReg(Reg, State); 865 866 if (TargetRegisterInfo::isPhysicalRegister(Reg)) 867 return MIB.addReg(TRI->getSubReg(Reg, SubIdx), State); 868 return MIB.addReg(Reg, State, SubIdx); 869 } 870 871 void ARMBaseInstrInfo:: 872 storeRegToStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I, 873 unsigned SrcReg, bool isKill, int FI, 874 const TargetRegisterClass *RC, 875 const TargetRegisterInfo *TRI) const { 876 DebugLoc DL; 877 if (I != MBB.end()) DL = I->getDebugLoc(); 878 MachineFunction &MF = *MBB.getParent(); 879 MachineFrameInfo &MFI = MF.getFrameInfo(); 880 unsigned Align = MFI.getObjectAlignment(FI); 881 882 MachineMemOperand *MMO = MF.getMachineMemOperand( 883 MachinePointerInfo::getFixedStack(MF, FI), MachineMemOperand::MOStore, 884 MFI.getObjectSize(FI), Align); 885 886 switch (RC->getSize()) { 887 case 4: 888 if (ARM::GPRRegClass.hasSubClassEq(RC)) { 889 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::STRi12)) 890 .addReg(SrcReg, getKillRegState(isKill)) 891 .addFrameIndex(FI).addImm(0).addMemOperand(MMO)); 892 } else if (ARM::SPRRegClass.hasSubClassEq(RC)) { 893 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTRS)) 894 .addReg(SrcReg, getKillRegState(isKill)) 895 .addFrameIndex(FI).addImm(0).addMemOperand(MMO)); 896 } else 897 llvm_unreachable("Unknown reg class!"); 898 break; 899 case 8: 900 if (ARM::DPRRegClass.hasSubClassEq(RC)) { 901 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTRD)) 902 .addReg(SrcReg, getKillRegState(isKill)) 903 .addFrameIndex(FI).addImm(0).addMemOperand(MMO)); 904 } else if (ARM::GPRPairRegClass.hasSubClassEq(RC)) { 905 if (Subtarget.hasV5TEOps()) { 906 MachineInstrBuilder MIB = BuildMI(MBB, I, DL, get(ARM::STRD)); 907 AddDReg(MIB, SrcReg, ARM::gsub_0, getKillRegState(isKill), TRI); 908 AddDReg(MIB, SrcReg, ARM::gsub_1, 0, TRI); 909 MIB.addFrameIndex(FI).addReg(0).addImm(0).addMemOperand(MMO); 910 911 AddDefaultPred(MIB); 912 } else { 913 // Fallback to STM instruction, which has existed since the dawn of 914 // time. 915 MachineInstrBuilder MIB = 916 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::STMIA)) 917 .addFrameIndex(FI).addMemOperand(MMO)); 918 AddDReg(MIB, SrcReg, ARM::gsub_0, getKillRegState(isKill), TRI); 919 AddDReg(MIB, SrcReg, ARM::gsub_1, 0, TRI); 920 } 921 } else 922 llvm_unreachable("Unknown reg class!"); 923 break; 924 case 16: 925 if (ARM::DPairRegClass.hasSubClassEq(RC)) { 926 // Use aligned spills if the stack can be realigned. 927 if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) { 928 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VST1q64)) 929 .addFrameIndex(FI).addImm(16) 930 .addReg(SrcReg, getKillRegState(isKill)) 931 .addMemOperand(MMO)); 932 } else { 933 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTMQIA)) 934 .addReg(SrcReg, getKillRegState(isKill)) 935 .addFrameIndex(FI) 936 .addMemOperand(MMO)); 937 } 938 } else 939 llvm_unreachable("Unknown reg class!"); 940 break; 941 case 24: 942 if (ARM::DTripleRegClass.hasSubClassEq(RC)) { 943 // Use aligned spills if the stack can be realigned. 944 if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) { 945 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VST1d64TPseudo)) 946 .addFrameIndex(FI).addImm(16) 947 .addReg(SrcReg, getKillRegState(isKill)) 948 .addMemOperand(MMO)); 949 } else { 950 MachineInstrBuilder MIB = 951 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTMDIA)) 952 .addFrameIndex(FI)) 953 .addMemOperand(MMO); 954 MIB = AddDReg(MIB, SrcReg, ARM::dsub_0, getKillRegState(isKill), TRI); 955 MIB = AddDReg(MIB, SrcReg, ARM::dsub_1, 0, TRI); 956 AddDReg(MIB, SrcReg, ARM::dsub_2, 0, TRI); 957 } 958 } else 959 llvm_unreachable("Unknown reg class!"); 960 break; 961 case 32: 962 if (ARM::QQPRRegClass.hasSubClassEq(RC) || ARM::DQuadRegClass.hasSubClassEq(RC)) { 963 if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) { 964 // FIXME: It's possible to only store part of the QQ register if the 965 // spilled def has a sub-register index. 966 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VST1d64QPseudo)) 967 .addFrameIndex(FI).addImm(16) 968 .addReg(SrcReg, getKillRegState(isKill)) 969 .addMemOperand(MMO)); 970 } else { 971 MachineInstrBuilder MIB = 972 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTMDIA)) 973 .addFrameIndex(FI)) 974 .addMemOperand(MMO); 975 MIB = AddDReg(MIB, SrcReg, ARM::dsub_0, getKillRegState(isKill), TRI); 976 MIB = AddDReg(MIB, SrcReg, ARM::dsub_1, 0, TRI); 977 MIB = AddDReg(MIB, SrcReg, ARM::dsub_2, 0, TRI); 978 AddDReg(MIB, SrcReg, ARM::dsub_3, 0, TRI); 979 } 980 } else 981 llvm_unreachable("Unknown reg class!"); 982 break; 983 case 64: 984 if (ARM::QQQQPRRegClass.hasSubClassEq(RC)) { 985 MachineInstrBuilder MIB = 986 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTMDIA)) 987 .addFrameIndex(FI)) 988 .addMemOperand(MMO); 989 MIB = AddDReg(MIB, SrcReg, ARM::dsub_0, getKillRegState(isKill), TRI); 990 MIB = AddDReg(MIB, SrcReg, ARM::dsub_1, 0, TRI); 991 MIB = AddDReg(MIB, SrcReg, ARM::dsub_2, 0, TRI); 992 MIB = AddDReg(MIB, SrcReg, ARM::dsub_3, 0, TRI); 993 MIB = AddDReg(MIB, SrcReg, ARM::dsub_4, 0, TRI); 994 MIB = AddDReg(MIB, SrcReg, ARM::dsub_5, 0, TRI); 995 MIB = AddDReg(MIB, SrcReg, ARM::dsub_6, 0, TRI); 996 AddDReg(MIB, SrcReg, ARM::dsub_7, 0, TRI); 997 } else 998 llvm_unreachable("Unknown reg class!"); 999 break; 1000 default: 1001 llvm_unreachable("Unknown reg class!"); 1002 } 1003 } 1004 1005 unsigned ARMBaseInstrInfo::isStoreToStackSlot(const MachineInstr &MI, 1006 int &FrameIndex) const { 1007 switch (MI.getOpcode()) { 1008 default: break; 1009 case ARM::STRrs: 1010 case ARM::t2STRs: // FIXME: don't use t2STRs to access frame. 1011 if (MI.getOperand(1).isFI() && MI.getOperand(2).isReg() && 1012 MI.getOperand(3).isImm() && MI.getOperand(2).getReg() == 0 && 1013 MI.getOperand(3).getImm() == 0) { 1014 FrameIndex = MI.getOperand(1).getIndex(); 1015 return MI.getOperand(0).getReg(); 1016 } 1017 break; 1018 case ARM::STRi12: 1019 case ARM::t2STRi12: 1020 case ARM::tSTRspi: 1021 case ARM::VSTRD: 1022 case ARM::VSTRS: 1023 if (MI.getOperand(1).isFI() && MI.getOperand(2).isImm() && 1024 MI.getOperand(2).getImm() == 0) { 1025 FrameIndex = MI.getOperand(1).getIndex(); 1026 return MI.getOperand(0).getReg(); 1027 } 1028 break; 1029 case ARM::VST1q64: 1030 case ARM::VST1d64TPseudo: 1031 case ARM::VST1d64QPseudo: 1032 if (MI.getOperand(0).isFI() && MI.getOperand(2).getSubReg() == 0) { 1033 FrameIndex = MI.getOperand(0).getIndex(); 1034 return MI.getOperand(2).getReg(); 1035 } 1036 break; 1037 case ARM::VSTMQIA: 1038 if (MI.getOperand(1).isFI() && MI.getOperand(0).getSubReg() == 0) { 1039 FrameIndex = MI.getOperand(1).getIndex(); 1040 return MI.getOperand(0).getReg(); 1041 } 1042 break; 1043 } 1044 1045 return 0; 1046 } 1047 1048 unsigned ARMBaseInstrInfo::isStoreToStackSlotPostFE(const MachineInstr &MI, 1049 int &FrameIndex) const { 1050 const MachineMemOperand *Dummy; 1051 return MI.mayStore() && hasStoreToStackSlot(MI, Dummy, FrameIndex); 1052 } 1053 1054 void ARMBaseInstrInfo:: 1055 loadRegFromStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I, 1056 unsigned DestReg, int FI, 1057 const TargetRegisterClass *RC, 1058 const TargetRegisterInfo *TRI) const { 1059 DebugLoc DL; 1060 if (I != MBB.end()) DL = I->getDebugLoc(); 1061 MachineFunction &MF = *MBB.getParent(); 1062 MachineFrameInfo &MFI = MF.getFrameInfo(); 1063 unsigned Align = MFI.getObjectAlignment(FI); 1064 MachineMemOperand *MMO = MF.getMachineMemOperand( 1065 MachinePointerInfo::getFixedStack(MF, FI), MachineMemOperand::MOLoad, 1066 MFI.getObjectSize(FI), Align); 1067 1068 switch (RC->getSize()) { 1069 case 4: 1070 if (ARM::GPRRegClass.hasSubClassEq(RC)) { 1071 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::LDRi12), DestReg) 1072 .addFrameIndex(FI).addImm(0).addMemOperand(MMO)); 1073 1074 } else if (ARM::SPRRegClass.hasSubClassEq(RC)) { 1075 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDRS), DestReg) 1076 .addFrameIndex(FI).addImm(0).addMemOperand(MMO)); 1077 } else 1078 llvm_unreachable("Unknown reg class!"); 1079 break; 1080 case 8: 1081 if (ARM::DPRRegClass.hasSubClassEq(RC)) { 1082 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDRD), DestReg) 1083 .addFrameIndex(FI).addImm(0).addMemOperand(MMO)); 1084 } else if (ARM::GPRPairRegClass.hasSubClassEq(RC)) { 1085 MachineInstrBuilder MIB; 1086 1087 if (Subtarget.hasV5TEOps()) { 1088 MIB = BuildMI(MBB, I, DL, get(ARM::LDRD)); 1089 AddDReg(MIB, DestReg, ARM::gsub_0, RegState::DefineNoRead, TRI); 1090 AddDReg(MIB, DestReg, ARM::gsub_1, RegState::DefineNoRead, TRI); 1091 MIB.addFrameIndex(FI).addReg(0).addImm(0).addMemOperand(MMO); 1092 1093 AddDefaultPred(MIB); 1094 } else { 1095 // Fallback to LDM instruction, which has existed since the dawn of 1096 // time. 1097 MIB = AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::LDMIA)) 1098 .addFrameIndex(FI).addMemOperand(MMO)); 1099 MIB = AddDReg(MIB, DestReg, ARM::gsub_0, RegState::DefineNoRead, TRI); 1100 MIB = AddDReg(MIB, DestReg, ARM::gsub_1, RegState::DefineNoRead, TRI); 1101 } 1102 1103 if (TargetRegisterInfo::isPhysicalRegister(DestReg)) 1104 MIB.addReg(DestReg, RegState::ImplicitDefine); 1105 } else 1106 llvm_unreachable("Unknown reg class!"); 1107 break; 1108 case 16: 1109 if (ARM::DPairRegClass.hasSubClassEq(RC)) { 1110 if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) { 1111 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLD1q64), DestReg) 1112 .addFrameIndex(FI).addImm(16) 1113 .addMemOperand(MMO)); 1114 } else { 1115 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDMQIA), DestReg) 1116 .addFrameIndex(FI) 1117 .addMemOperand(MMO)); 1118 } 1119 } else 1120 llvm_unreachable("Unknown reg class!"); 1121 break; 1122 case 24: 1123 if (ARM::DTripleRegClass.hasSubClassEq(RC)) { 1124 if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) { 1125 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLD1d64TPseudo), DestReg) 1126 .addFrameIndex(FI).addImm(16) 1127 .addMemOperand(MMO)); 1128 } else { 1129 MachineInstrBuilder MIB = 1130 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDMDIA)) 1131 .addFrameIndex(FI) 1132 .addMemOperand(MMO)); 1133 MIB = AddDReg(MIB, DestReg, ARM::dsub_0, RegState::DefineNoRead, TRI); 1134 MIB = AddDReg(MIB, DestReg, ARM::dsub_1, RegState::DefineNoRead, TRI); 1135 MIB = AddDReg(MIB, DestReg, ARM::dsub_2, RegState::DefineNoRead, TRI); 1136 if (TargetRegisterInfo::isPhysicalRegister(DestReg)) 1137 MIB.addReg(DestReg, RegState::ImplicitDefine); 1138 } 1139 } else 1140 llvm_unreachable("Unknown reg class!"); 1141 break; 1142 case 32: 1143 if (ARM::QQPRRegClass.hasSubClassEq(RC) || ARM::DQuadRegClass.hasSubClassEq(RC)) { 1144 if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) { 1145 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLD1d64QPseudo), DestReg) 1146 .addFrameIndex(FI).addImm(16) 1147 .addMemOperand(MMO)); 1148 } else { 1149 MachineInstrBuilder MIB = 1150 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDMDIA)) 1151 .addFrameIndex(FI)) 1152 .addMemOperand(MMO); 1153 MIB = AddDReg(MIB, DestReg, ARM::dsub_0, RegState::DefineNoRead, TRI); 1154 MIB = AddDReg(MIB, DestReg, ARM::dsub_1, RegState::DefineNoRead, TRI); 1155 MIB = AddDReg(MIB, DestReg, ARM::dsub_2, RegState::DefineNoRead, TRI); 1156 MIB = AddDReg(MIB, DestReg, ARM::dsub_3, RegState::DefineNoRead, TRI); 1157 if (TargetRegisterInfo::isPhysicalRegister(DestReg)) 1158 MIB.addReg(DestReg, RegState::ImplicitDefine); 1159 } 1160 } else 1161 llvm_unreachable("Unknown reg class!"); 1162 break; 1163 case 64: 1164 if (ARM::QQQQPRRegClass.hasSubClassEq(RC)) { 1165 MachineInstrBuilder MIB = 1166 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDMDIA)) 1167 .addFrameIndex(FI)) 1168 .addMemOperand(MMO); 1169 MIB = AddDReg(MIB, DestReg, ARM::dsub_0, RegState::DefineNoRead, TRI); 1170 MIB = AddDReg(MIB, DestReg, ARM::dsub_1, RegState::DefineNoRead, TRI); 1171 MIB = AddDReg(MIB, DestReg, ARM::dsub_2, RegState::DefineNoRead, TRI); 1172 MIB = AddDReg(MIB, DestReg, ARM::dsub_3, RegState::DefineNoRead, TRI); 1173 MIB = AddDReg(MIB, DestReg, ARM::dsub_4, RegState::DefineNoRead, TRI); 1174 MIB = AddDReg(MIB, DestReg, ARM::dsub_5, RegState::DefineNoRead, TRI); 1175 MIB = AddDReg(MIB, DestReg, ARM::dsub_6, RegState::DefineNoRead, TRI); 1176 MIB = AddDReg(MIB, DestReg, ARM::dsub_7, RegState::DefineNoRead, TRI); 1177 if (TargetRegisterInfo::isPhysicalRegister(DestReg)) 1178 MIB.addReg(DestReg, RegState::ImplicitDefine); 1179 } else 1180 llvm_unreachable("Unknown reg class!"); 1181 break; 1182 default: 1183 llvm_unreachable("Unknown regclass!"); 1184 } 1185 } 1186 1187 unsigned ARMBaseInstrInfo::isLoadFromStackSlot(const MachineInstr &MI, 1188 int &FrameIndex) const { 1189 switch (MI.getOpcode()) { 1190 default: break; 1191 case ARM::LDRrs: 1192 case ARM::t2LDRs: // FIXME: don't use t2LDRs to access frame. 1193 if (MI.getOperand(1).isFI() && MI.getOperand(2).isReg() && 1194 MI.getOperand(3).isImm() && MI.getOperand(2).getReg() == 0 && 1195 MI.getOperand(3).getImm() == 0) { 1196 FrameIndex = MI.getOperand(1).getIndex(); 1197 return MI.getOperand(0).getReg(); 1198 } 1199 break; 1200 case ARM::LDRi12: 1201 case ARM::t2LDRi12: 1202 case ARM::tLDRspi: 1203 case ARM::VLDRD: 1204 case ARM::VLDRS: 1205 if (MI.getOperand(1).isFI() && MI.getOperand(2).isImm() && 1206 MI.getOperand(2).getImm() == 0) { 1207 FrameIndex = MI.getOperand(1).getIndex(); 1208 return MI.getOperand(0).getReg(); 1209 } 1210 break; 1211 case ARM::VLD1q64: 1212 case ARM::VLD1d64TPseudo: 1213 case ARM::VLD1d64QPseudo: 1214 if (MI.getOperand(1).isFI() && MI.getOperand(0).getSubReg() == 0) { 1215 FrameIndex = MI.getOperand(1).getIndex(); 1216 return MI.getOperand(0).getReg(); 1217 } 1218 break; 1219 case ARM::VLDMQIA: 1220 if (MI.getOperand(1).isFI() && MI.getOperand(0).getSubReg() == 0) { 1221 FrameIndex = MI.getOperand(1).getIndex(); 1222 return MI.getOperand(0).getReg(); 1223 } 1224 break; 1225 } 1226 1227 return 0; 1228 } 1229 1230 unsigned ARMBaseInstrInfo::isLoadFromStackSlotPostFE(const MachineInstr &MI, 1231 int &FrameIndex) const { 1232 const MachineMemOperand *Dummy; 1233 return MI.mayLoad() && hasLoadFromStackSlot(MI, Dummy, FrameIndex); 1234 } 1235 1236 /// \brief Expands MEMCPY to either LDMIA/STMIA or LDMIA_UPD/STMID_UPD 1237 /// depending on whether the result is used. 1238 void ARMBaseInstrInfo::expandMEMCPY(MachineBasicBlock::iterator MI) const { 1239 bool isThumb1 = Subtarget.isThumb1Only(); 1240 bool isThumb2 = Subtarget.isThumb2(); 1241 const ARMBaseInstrInfo *TII = Subtarget.getInstrInfo(); 1242 1243 DebugLoc dl = MI->getDebugLoc(); 1244 MachineBasicBlock *BB = MI->getParent(); 1245 1246 MachineInstrBuilder LDM, STM; 1247 if (isThumb1 || !MI->getOperand(1).isDead()) { 1248 LDM = BuildMI(*BB, MI, dl, TII->get(isThumb2 ? ARM::t2LDMIA_UPD 1249 : isThumb1 ? ARM::tLDMIA_UPD 1250 : ARM::LDMIA_UPD)) 1251 .addOperand(MI->getOperand(1)); 1252 } else { 1253 LDM = BuildMI(*BB, MI, dl, TII->get(isThumb2 ? ARM::t2LDMIA : ARM::LDMIA)); 1254 } 1255 1256 if (isThumb1 || !MI->getOperand(0).isDead()) { 1257 STM = BuildMI(*BB, MI, dl, TII->get(isThumb2 ? ARM::t2STMIA_UPD 1258 : isThumb1 ? ARM::tSTMIA_UPD 1259 : ARM::STMIA_UPD)) 1260 .addOperand(MI->getOperand(0)); 1261 } else { 1262 STM = BuildMI(*BB, MI, dl, TII->get(isThumb2 ? ARM::t2STMIA : ARM::STMIA)); 1263 } 1264 1265 AddDefaultPred(LDM.addOperand(MI->getOperand(3))); 1266 AddDefaultPred(STM.addOperand(MI->getOperand(2))); 1267 1268 // Sort the scratch registers into ascending order. 1269 const TargetRegisterInfo &TRI = getRegisterInfo(); 1270 llvm::SmallVector<unsigned, 6> ScratchRegs; 1271 for(unsigned I = 5; I < MI->getNumOperands(); ++I) 1272 ScratchRegs.push_back(MI->getOperand(I).getReg()); 1273 std::sort(ScratchRegs.begin(), ScratchRegs.end(), 1274 [&TRI](const unsigned &Reg1, 1275 const unsigned &Reg2) -> bool { 1276 return TRI.getEncodingValue(Reg1) < 1277 TRI.getEncodingValue(Reg2); 1278 }); 1279 1280 for (const auto &Reg : ScratchRegs) { 1281 LDM.addReg(Reg, RegState::Define); 1282 STM.addReg(Reg, RegState::Kill); 1283 } 1284 1285 BB->erase(MI); 1286 } 1287 1288 1289 bool ARMBaseInstrInfo::expandPostRAPseudo(MachineInstr &MI) const { 1290 if (MI.getOpcode() == TargetOpcode::LOAD_STACK_GUARD) { 1291 assert(getSubtarget().getTargetTriple().isOSBinFormatMachO() && 1292 "LOAD_STACK_GUARD currently supported only for MachO."); 1293 expandLoadStackGuard(MI); 1294 MI.getParent()->erase(MI); 1295 return true; 1296 } 1297 1298 if (MI.getOpcode() == ARM::MEMCPY) { 1299 expandMEMCPY(MI); 1300 return true; 1301 } 1302 1303 // This hook gets to expand COPY instructions before they become 1304 // copyPhysReg() calls. Look for VMOVS instructions that can legally be 1305 // widened to VMOVD. We prefer the VMOVD when possible because it may be 1306 // changed into a VORR that can go down the NEON pipeline. 1307 if (!MI.isCopy() || Subtarget.dontWidenVMOVS() || Subtarget.isFPOnlySP()) 1308 return false; 1309 1310 // Look for a copy between even S-registers. That is where we keep floats 1311 // when using NEON v2f32 instructions for f32 arithmetic. 1312 unsigned DstRegS = MI.getOperand(0).getReg(); 1313 unsigned SrcRegS = MI.getOperand(1).getReg(); 1314 if (!ARM::SPRRegClass.contains(DstRegS, SrcRegS)) 1315 return false; 1316 1317 const TargetRegisterInfo *TRI = &getRegisterInfo(); 1318 unsigned DstRegD = TRI->getMatchingSuperReg(DstRegS, ARM::ssub_0, 1319 &ARM::DPRRegClass); 1320 unsigned SrcRegD = TRI->getMatchingSuperReg(SrcRegS, ARM::ssub_0, 1321 &ARM::DPRRegClass); 1322 if (!DstRegD || !SrcRegD) 1323 return false; 1324 1325 // We want to widen this into a DstRegD = VMOVD SrcRegD copy. This is only 1326 // legal if the COPY already defines the full DstRegD, and it isn't a 1327 // sub-register insertion. 1328 if (!MI.definesRegister(DstRegD, TRI) || MI.readsRegister(DstRegD, TRI)) 1329 return false; 1330 1331 // A dead copy shouldn't show up here, but reject it just in case. 1332 if (MI.getOperand(0).isDead()) 1333 return false; 1334 1335 // All clear, widen the COPY. 1336 DEBUG(dbgs() << "widening: " << MI); 1337 MachineInstrBuilder MIB(*MI.getParent()->getParent(), MI); 1338 1339 // Get rid of the old <imp-def> of DstRegD. Leave it if it defines a Q-reg 1340 // or some other super-register. 1341 int ImpDefIdx = MI.findRegisterDefOperandIdx(DstRegD); 1342 if (ImpDefIdx != -1) 1343 MI.RemoveOperand(ImpDefIdx); 1344 1345 // Change the opcode and operands. 1346 MI.setDesc(get(ARM::VMOVD)); 1347 MI.getOperand(0).setReg(DstRegD); 1348 MI.getOperand(1).setReg(SrcRegD); 1349 AddDefaultPred(MIB); 1350 1351 // We are now reading SrcRegD instead of SrcRegS. This may upset the 1352 // register scavenger and machine verifier, so we need to indicate that we 1353 // are reading an undefined value from SrcRegD, but a proper value from 1354 // SrcRegS. 1355 MI.getOperand(1).setIsUndef(); 1356 MIB.addReg(SrcRegS, RegState::Implicit); 1357 1358 // SrcRegD may actually contain an unrelated value in the ssub_1 1359 // sub-register. Don't kill it. Only kill the ssub_0 sub-register. 1360 if (MI.getOperand(1).isKill()) { 1361 MI.getOperand(1).setIsKill(false); 1362 MI.addRegisterKilled(SrcRegS, TRI, true); 1363 } 1364 1365 DEBUG(dbgs() << "replaced by: " << MI); 1366 return true; 1367 } 1368 1369 /// Create a copy of a const pool value. Update CPI to the new index and return 1370 /// the label UID. 1371 static unsigned duplicateCPV(MachineFunction &MF, unsigned &CPI) { 1372 MachineConstantPool *MCP = MF.getConstantPool(); 1373 ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>(); 1374 1375 const MachineConstantPoolEntry &MCPE = MCP->getConstants()[CPI]; 1376 assert(MCPE.isMachineConstantPoolEntry() && 1377 "Expecting a machine constantpool entry!"); 1378 ARMConstantPoolValue *ACPV = 1379 static_cast<ARMConstantPoolValue*>(MCPE.Val.MachineCPVal); 1380 1381 unsigned PCLabelId = AFI->createPICLabelUId(); 1382 ARMConstantPoolValue *NewCPV = nullptr; 1383 1384 // FIXME: The below assumes PIC relocation model and that the function 1385 // is Thumb mode (t1 or t2). PCAdjustment would be 8 for ARM mode PIC, and 1386 // zero for non-PIC in ARM or Thumb. The callers are all of thumb LDR 1387 // instructions, so that's probably OK, but is PIC always correct when 1388 // we get here? 1389 if (ACPV->isGlobalValue()) 1390 NewCPV = ARMConstantPoolConstant::Create( 1391 cast<ARMConstantPoolConstant>(ACPV)->getGV(), PCLabelId, ARMCP::CPValue, 1392 4, ACPV->getModifier(), ACPV->mustAddCurrentAddress()); 1393 else if (ACPV->isExtSymbol()) 1394 NewCPV = ARMConstantPoolSymbol:: 1395 Create(MF.getFunction()->getContext(), 1396 cast<ARMConstantPoolSymbol>(ACPV)->getSymbol(), PCLabelId, 4); 1397 else if (ACPV->isBlockAddress()) 1398 NewCPV = ARMConstantPoolConstant:: 1399 Create(cast<ARMConstantPoolConstant>(ACPV)->getBlockAddress(), PCLabelId, 1400 ARMCP::CPBlockAddress, 4); 1401 else if (ACPV->isLSDA()) 1402 NewCPV = ARMConstantPoolConstant::Create(MF.getFunction(), PCLabelId, 1403 ARMCP::CPLSDA, 4); 1404 else if (ACPV->isMachineBasicBlock()) 1405 NewCPV = ARMConstantPoolMBB:: 1406 Create(MF.getFunction()->getContext(), 1407 cast<ARMConstantPoolMBB>(ACPV)->getMBB(), PCLabelId, 4); 1408 else 1409 llvm_unreachable("Unexpected ARM constantpool value type!!"); 1410 CPI = MCP->getConstantPoolIndex(NewCPV, MCPE.getAlignment()); 1411 return PCLabelId; 1412 } 1413 1414 void ARMBaseInstrInfo::reMaterialize(MachineBasicBlock &MBB, 1415 MachineBasicBlock::iterator I, 1416 unsigned DestReg, unsigned SubIdx, 1417 const MachineInstr &Orig, 1418 const TargetRegisterInfo &TRI) const { 1419 unsigned Opcode = Orig.getOpcode(); 1420 switch (Opcode) { 1421 default: { 1422 MachineInstr *MI = MBB.getParent()->CloneMachineInstr(&Orig); 1423 MI->substituteRegister(Orig.getOperand(0).getReg(), DestReg, SubIdx, TRI); 1424 MBB.insert(I, MI); 1425 break; 1426 } 1427 case ARM::tLDRpci_pic: 1428 case ARM::t2LDRpci_pic: { 1429 MachineFunction &MF = *MBB.getParent(); 1430 unsigned CPI = Orig.getOperand(1).getIndex(); 1431 unsigned PCLabelId = duplicateCPV(MF, CPI); 1432 MachineInstrBuilder MIB = 1433 BuildMI(MBB, I, Orig.getDebugLoc(), get(Opcode), DestReg) 1434 .addConstantPoolIndex(CPI) 1435 .addImm(PCLabelId); 1436 MIB->setMemRefs(Orig.memoperands_begin(), Orig.memoperands_end()); 1437 break; 1438 } 1439 } 1440 } 1441 1442 MachineInstr *ARMBaseInstrInfo::duplicate(MachineInstr &Orig, 1443 MachineFunction &MF) const { 1444 MachineInstr *MI = TargetInstrInfo::duplicate(Orig, MF); 1445 switch (Orig.getOpcode()) { 1446 case ARM::tLDRpci_pic: 1447 case ARM::t2LDRpci_pic: { 1448 unsigned CPI = Orig.getOperand(1).getIndex(); 1449 unsigned PCLabelId = duplicateCPV(MF, CPI); 1450 Orig.getOperand(1).setIndex(CPI); 1451 Orig.getOperand(2).setImm(PCLabelId); 1452 break; 1453 } 1454 } 1455 return MI; 1456 } 1457 1458 bool ARMBaseInstrInfo::produceSameValue(const MachineInstr &MI0, 1459 const MachineInstr &MI1, 1460 const MachineRegisterInfo *MRI) const { 1461 unsigned Opcode = MI0.getOpcode(); 1462 if (Opcode == ARM::t2LDRpci || 1463 Opcode == ARM::t2LDRpci_pic || 1464 Opcode == ARM::tLDRpci || 1465 Opcode == ARM::tLDRpci_pic || 1466 Opcode == ARM::LDRLIT_ga_pcrel || 1467 Opcode == ARM::LDRLIT_ga_pcrel_ldr || 1468 Opcode == ARM::tLDRLIT_ga_pcrel || 1469 Opcode == ARM::MOV_ga_pcrel || 1470 Opcode == ARM::MOV_ga_pcrel_ldr || 1471 Opcode == ARM::t2MOV_ga_pcrel) { 1472 if (MI1.getOpcode() != Opcode) 1473 return false; 1474 if (MI0.getNumOperands() != MI1.getNumOperands()) 1475 return false; 1476 1477 const MachineOperand &MO0 = MI0.getOperand(1); 1478 const MachineOperand &MO1 = MI1.getOperand(1); 1479 if (MO0.getOffset() != MO1.getOffset()) 1480 return false; 1481 1482 if (Opcode == ARM::LDRLIT_ga_pcrel || 1483 Opcode == ARM::LDRLIT_ga_pcrel_ldr || 1484 Opcode == ARM::tLDRLIT_ga_pcrel || 1485 Opcode == ARM::MOV_ga_pcrel || 1486 Opcode == ARM::MOV_ga_pcrel_ldr || 1487 Opcode == ARM::t2MOV_ga_pcrel) 1488 // Ignore the PC labels. 1489 return MO0.getGlobal() == MO1.getGlobal(); 1490 1491 const MachineFunction *MF = MI0.getParent()->getParent(); 1492 const MachineConstantPool *MCP = MF->getConstantPool(); 1493 int CPI0 = MO0.getIndex(); 1494 int CPI1 = MO1.getIndex(); 1495 const MachineConstantPoolEntry &MCPE0 = MCP->getConstants()[CPI0]; 1496 const MachineConstantPoolEntry &MCPE1 = MCP->getConstants()[CPI1]; 1497 bool isARMCP0 = MCPE0.isMachineConstantPoolEntry(); 1498 bool isARMCP1 = MCPE1.isMachineConstantPoolEntry(); 1499 if (isARMCP0 && isARMCP1) { 1500 ARMConstantPoolValue *ACPV0 = 1501 static_cast<ARMConstantPoolValue*>(MCPE0.Val.MachineCPVal); 1502 ARMConstantPoolValue *ACPV1 = 1503 static_cast<ARMConstantPoolValue*>(MCPE1.Val.MachineCPVal); 1504 return ACPV0->hasSameValue(ACPV1); 1505 } else if (!isARMCP0 && !isARMCP1) { 1506 return MCPE0.Val.ConstVal == MCPE1.Val.ConstVal; 1507 } 1508 return false; 1509 } else if (Opcode == ARM::PICLDR) { 1510 if (MI1.getOpcode() != Opcode) 1511 return false; 1512 if (MI0.getNumOperands() != MI1.getNumOperands()) 1513 return false; 1514 1515 unsigned Addr0 = MI0.getOperand(1).getReg(); 1516 unsigned Addr1 = MI1.getOperand(1).getReg(); 1517 if (Addr0 != Addr1) { 1518 if (!MRI || 1519 !TargetRegisterInfo::isVirtualRegister(Addr0) || 1520 !TargetRegisterInfo::isVirtualRegister(Addr1)) 1521 return false; 1522 1523 // This assumes SSA form. 1524 MachineInstr *Def0 = MRI->getVRegDef(Addr0); 1525 MachineInstr *Def1 = MRI->getVRegDef(Addr1); 1526 // Check if the loaded value, e.g. a constantpool of a global address, are 1527 // the same. 1528 if (!produceSameValue(*Def0, *Def1, MRI)) 1529 return false; 1530 } 1531 1532 for (unsigned i = 3, e = MI0.getNumOperands(); i != e; ++i) { 1533 // %vreg12<def> = PICLDR %vreg11, 0, pred:14, pred:%noreg 1534 const MachineOperand &MO0 = MI0.getOperand(i); 1535 const MachineOperand &MO1 = MI1.getOperand(i); 1536 if (!MO0.isIdenticalTo(MO1)) 1537 return false; 1538 } 1539 return true; 1540 } 1541 1542 return MI0.isIdenticalTo(MI1, MachineInstr::IgnoreVRegDefs); 1543 } 1544 1545 /// areLoadsFromSameBasePtr - This is used by the pre-regalloc scheduler to 1546 /// determine if two loads are loading from the same base address. It should 1547 /// only return true if the base pointers are the same and the only differences 1548 /// between the two addresses is the offset. It also returns the offsets by 1549 /// reference. 1550 /// 1551 /// FIXME: remove this in favor of the MachineInstr interface once pre-RA-sched 1552 /// is permanently disabled. 1553 bool ARMBaseInstrInfo::areLoadsFromSameBasePtr(SDNode *Load1, SDNode *Load2, 1554 int64_t &Offset1, 1555 int64_t &Offset2) const { 1556 // Don't worry about Thumb: just ARM and Thumb2. 1557 if (Subtarget.isThumb1Only()) return false; 1558 1559 if (!Load1->isMachineOpcode() || !Load2->isMachineOpcode()) 1560 return false; 1561 1562 switch (Load1->getMachineOpcode()) { 1563 default: 1564 return false; 1565 case ARM::LDRi12: 1566 case ARM::LDRBi12: 1567 case ARM::LDRD: 1568 case ARM::LDRH: 1569 case ARM::LDRSB: 1570 case ARM::LDRSH: 1571 case ARM::VLDRD: 1572 case ARM::VLDRS: 1573 case ARM::t2LDRi8: 1574 case ARM::t2LDRBi8: 1575 case ARM::t2LDRDi8: 1576 case ARM::t2LDRSHi8: 1577 case ARM::t2LDRi12: 1578 case ARM::t2LDRBi12: 1579 case ARM::t2LDRSHi12: 1580 break; 1581 } 1582 1583 switch (Load2->getMachineOpcode()) { 1584 default: 1585 return false; 1586 case ARM::LDRi12: 1587 case ARM::LDRBi12: 1588 case ARM::LDRD: 1589 case ARM::LDRH: 1590 case ARM::LDRSB: 1591 case ARM::LDRSH: 1592 case ARM::VLDRD: 1593 case ARM::VLDRS: 1594 case ARM::t2LDRi8: 1595 case ARM::t2LDRBi8: 1596 case ARM::t2LDRSHi8: 1597 case ARM::t2LDRi12: 1598 case ARM::t2LDRBi12: 1599 case ARM::t2LDRSHi12: 1600 break; 1601 } 1602 1603 // Check if base addresses and chain operands match. 1604 if (Load1->getOperand(0) != Load2->getOperand(0) || 1605 Load1->getOperand(4) != Load2->getOperand(4)) 1606 return false; 1607 1608 // Index should be Reg0. 1609 if (Load1->getOperand(3) != Load2->getOperand(3)) 1610 return false; 1611 1612 // Determine the offsets. 1613 if (isa<ConstantSDNode>(Load1->getOperand(1)) && 1614 isa<ConstantSDNode>(Load2->getOperand(1))) { 1615 Offset1 = cast<ConstantSDNode>(Load1->getOperand(1))->getSExtValue(); 1616 Offset2 = cast<ConstantSDNode>(Load2->getOperand(1))->getSExtValue(); 1617 return true; 1618 } 1619 1620 return false; 1621 } 1622 1623 /// shouldScheduleLoadsNear - This is a used by the pre-regalloc scheduler to 1624 /// determine (in conjunction with areLoadsFromSameBasePtr) if two loads should 1625 /// be scheduled togther. On some targets if two loads are loading from 1626 /// addresses in the same cache line, it's better if they are scheduled 1627 /// together. This function takes two integers that represent the load offsets 1628 /// from the common base address. It returns true if it decides it's desirable 1629 /// to schedule the two loads together. "NumLoads" is the number of loads that 1630 /// have already been scheduled after Load1. 1631 /// 1632 /// FIXME: remove this in favor of the MachineInstr interface once pre-RA-sched 1633 /// is permanently disabled. 1634 bool ARMBaseInstrInfo::shouldScheduleLoadsNear(SDNode *Load1, SDNode *Load2, 1635 int64_t Offset1, int64_t Offset2, 1636 unsigned NumLoads) const { 1637 // Don't worry about Thumb: just ARM and Thumb2. 1638 if (Subtarget.isThumb1Only()) return false; 1639 1640 assert(Offset2 > Offset1); 1641 1642 if ((Offset2 - Offset1) / 8 > 64) 1643 return false; 1644 1645 // Check if the machine opcodes are different. If they are different 1646 // then we consider them to not be of the same base address, 1647 // EXCEPT in the case of Thumb2 byte loads where one is LDRBi8 and the other LDRBi12. 1648 // In this case, they are considered to be the same because they are different 1649 // encoding forms of the same basic instruction. 1650 if ((Load1->getMachineOpcode() != Load2->getMachineOpcode()) && 1651 !((Load1->getMachineOpcode() == ARM::t2LDRBi8 && 1652 Load2->getMachineOpcode() == ARM::t2LDRBi12) || 1653 (Load1->getMachineOpcode() == ARM::t2LDRBi12 && 1654 Load2->getMachineOpcode() == ARM::t2LDRBi8))) 1655 return false; // FIXME: overly conservative? 1656 1657 // Four loads in a row should be sufficient. 1658 if (NumLoads >= 3) 1659 return false; 1660 1661 return true; 1662 } 1663 1664 bool ARMBaseInstrInfo::isSchedulingBoundary(const MachineInstr &MI, 1665 const MachineBasicBlock *MBB, 1666 const MachineFunction &MF) const { 1667 // Debug info is never a scheduling boundary. It's necessary to be explicit 1668 // due to the special treatment of IT instructions below, otherwise a 1669 // dbg_value followed by an IT will result in the IT instruction being 1670 // considered a scheduling hazard, which is wrong. It should be the actual 1671 // instruction preceding the dbg_value instruction(s), just like it is 1672 // when debug info is not present. 1673 if (MI.isDebugValue()) 1674 return false; 1675 1676 // Terminators and labels can't be scheduled around. 1677 if (MI.isTerminator() || MI.isPosition()) 1678 return true; 1679 1680 // Treat the start of the IT block as a scheduling boundary, but schedule 1681 // t2IT along with all instructions following it. 1682 // FIXME: This is a big hammer. But the alternative is to add all potential 1683 // true and anti dependencies to IT block instructions as implicit operands 1684 // to the t2IT instruction. The added compile time and complexity does not 1685 // seem worth it. 1686 MachineBasicBlock::const_iterator I = MI; 1687 // Make sure to skip any dbg_value instructions 1688 while (++I != MBB->end() && I->isDebugValue()) 1689 ; 1690 if (I != MBB->end() && I->getOpcode() == ARM::t2IT) 1691 return true; 1692 1693 // Don't attempt to schedule around any instruction that defines 1694 // a stack-oriented pointer, as it's unlikely to be profitable. This 1695 // saves compile time, because it doesn't require every single 1696 // stack slot reference to depend on the instruction that does the 1697 // modification. 1698 // Calls don't actually change the stack pointer, even if they have imp-defs. 1699 // No ARM calling conventions change the stack pointer. (X86 calling 1700 // conventions sometimes do). 1701 if (!MI.isCall() && MI.definesRegister(ARM::SP)) 1702 return true; 1703 1704 return false; 1705 } 1706 1707 bool ARMBaseInstrInfo:: 1708 isProfitableToIfCvt(MachineBasicBlock &MBB, 1709 unsigned NumCycles, unsigned ExtraPredCycles, 1710 BranchProbability Probability) const { 1711 if (!NumCycles) 1712 return false; 1713 1714 // If we are optimizing for size, see if the branch in the predecessor can be 1715 // lowered to cbn?z by the constant island lowering pass, and return false if 1716 // so. This results in a shorter instruction sequence. 1717 if (MBB.getParent()->getFunction()->optForSize()) { 1718 MachineBasicBlock *Pred = *MBB.pred_begin(); 1719 if (!Pred->empty()) { 1720 MachineInstr *LastMI = &*Pred->rbegin(); 1721 if (LastMI->getOpcode() == ARM::t2Bcc) { 1722 MachineBasicBlock::iterator CmpMI = LastMI; 1723 if (CmpMI != Pred->begin()) { 1724 --CmpMI; 1725 if (CmpMI->getOpcode() == ARM::tCMPi8 || 1726 CmpMI->getOpcode() == ARM::t2CMPri) { 1727 unsigned Reg = CmpMI->getOperand(0).getReg(); 1728 unsigned PredReg = 0; 1729 ARMCC::CondCodes P = getInstrPredicate(*CmpMI, PredReg); 1730 if (P == ARMCC::AL && CmpMI->getOperand(1).getImm() == 0 && 1731 isARMLowRegister(Reg)) 1732 return false; 1733 } 1734 } 1735 } 1736 } 1737 } 1738 1739 // Attempt to estimate the relative costs of predication versus branching. 1740 // Here we scale up each component of UnpredCost to avoid precision issue when 1741 // scaling NumCycles by Probability. 1742 const unsigned ScalingUpFactor = 1024; 1743 unsigned UnpredCost = Probability.scale(NumCycles * ScalingUpFactor); 1744 UnpredCost += ScalingUpFactor; // The branch itself 1745 UnpredCost += Subtarget.getMispredictionPenalty() * ScalingUpFactor / 10; 1746 1747 return (NumCycles + ExtraPredCycles) * ScalingUpFactor <= UnpredCost; 1748 } 1749 1750 bool ARMBaseInstrInfo:: 1751 isProfitableToIfCvt(MachineBasicBlock &TMBB, 1752 unsigned TCycles, unsigned TExtra, 1753 MachineBasicBlock &FMBB, 1754 unsigned FCycles, unsigned FExtra, 1755 BranchProbability Probability) const { 1756 if (!TCycles || !FCycles) 1757 return false; 1758 1759 // Attempt to estimate the relative costs of predication versus branching. 1760 // Here we scale up each component of UnpredCost to avoid precision issue when 1761 // scaling TCycles/FCycles by Probability. 1762 const unsigned ScalingUpFactor = 1024; 1763 unsigned TUnpredCost = Probability.scale(TCycles * ScalingUpFactor); 1764 unsigned FUnpredCost = 1765 Probability.getCompl().scale(FCycles * ScalingUpFactor); 1766 unsigned UnpredCost = TUnpredCost + FUnpredCost; 1767 UnpredCost += 1 * ScalingUpFactor; // The branch itself 1768 UnpredCost += Subtarget.getMispredictionPenalty() * ScalingUpFactor / 10; 1769 1770 return (TCycles + FCycles + TExtra + FExtra) * ScalingUpFactor <= UnpredCost; 1771 } 1772 1773 bool 1774 ARMBaseInstrInfo::isProfitableToUnpredicate(MachineBasicBlock &TMBB, 1775 MachineBasicBlock &FMBB) const { 1776 // Reduce false anti-dependencies to let the target's out-of-order execution 1777 // engine do its thing. 1778 return Subtarget.isProfitableToUnpredicate(); 1779 } 1780 1781 /// getInstrPredicate - If instruction is predicated, returns its predicate 1782 /// condition, otherwise returns AL. It also returns the condition code 1783 /// register by reference. 1784 ARMCC::CondCodes llvm::getInstrPredicate(const MachineInstr &MI, 1785 unsigned &PredReg) { 1786 int PIdx = MI.findFirstPredOperandIdx(); 1787 if (PIdx == -1) { 1788 PredReg = 0; 1789 return ARMCC::AL; 1790 } 1791 1792 PredReg = MI.getOperand(PIdx+1).getReg(); 1793 return (ARMCC::CondCodes)MI.getOperand(PIdx).getImm(); 1794 } 1795 1796 1797 unsigned llvm::getMatchingCondBranchOpcode(unsigned Opc) { 1798 if (Opc == ARM::B) 1799 return ARM::Bcc; 1800 if (Opc == ARM::tB) 1801 return ARM::tBcc; 1802 if (Opc == ARM::t2B) 1803 return ARM::t2Bcc; 1804 1805 llvm_unreachable("Unknown unconditional branch opcode!"); 1806 } 1807 1808 MachineInstr *ARMBaseInstrInfo::commuteInstructionImpl(MachineInstr &MI, 1809 bool NewMI, 1810 unsigned OpIdx1, 1811 unsigned OpIdx2) const { 1812 switch (MI.getOpcode()) { 1813 case ARM::MOVCCr: 1814 case ARM::t2MOVCCr: { 1815 // MOVCC can be commuted by inverting the condition. 1816 unsigned PredReg = 0; 1817 ARMCC::CondCodes CC = getInstrPredicate(MI, PredReg); 1818 // MOVCC AL can't be inverted. Shouldn't happen. 1819 if (CC == ARMCC::AL || PredReg != ARM::CPSR) 1820 return nullptr; 1821 MachineInstr *CommutedMI = 1822 TargetInstrInfo::commuteInstructionImpl(MI, NewMI, OpIdx1, OpIdx2); 1823 if (!CommutedMI) 1824 return nullptr; 1825 // After swapping the MOVCC operands, also invert the condition. 1826 CommutedMI->getOperand(CommutedMI->findFirstPredOperandIdx()) 1827 .setImm(ARMCC::getOppositeCondition(CC)); 1828 return CommutedMI; 1829 } 1830 } 1831 return TargetInstrInfo::commuteInstructionImpl(MI, NewMI, OpIdx1, OpIdx2); 1832 } 1833 1834 /// Identify instructions that can be folded into a MOVCC instruction, and 1835 /// return the defining instruction. 1836 static MachineInstr *canFoldIntoMOVCC(unsigned Reg, 1837 const MachineRegisterInfo &MRI, 1838 const TargetInstrInfo *TII) { 1839 if (!TargetRegisterInfo::isVirtualRegister(Reg)) 1840 return nullptr; 1841 if (!MRI.hasOneNonDBGUse(Reg)) 1842 return nullptr; 1843 MachineInstr *MI = MRI.getVRegDef(Reg); 1844 if (!MI) 1845 return nullptr; 1846 // MI is folded into the MOVCC by predicating it. 1847 if (!MI->isPredicable()) 1848 return nullptr; 1849 // Check if MI has any non-dead defs or physreg uses. This also detects 1850 // predicated instructions which will be reading CPSR. 1851 for (unsigned i = 1, e = MI->getNumOperands(); i != e; ++i) { 1852 const MachineOperand &MO = MI->getOperand(i); 1853 // Reject frame index operands, PEI can't handle the predicated pseudos. 1854 if (MO.isFI() || MO.isCPI() || MO.isJTI()) 1855 return nullptr; 1856 if (!MO.isReg()) 1857 continue; 1858 // MI can't have any tied operands, that would conflict with predication. 1859 if (MO.isTied()) 1860 return nullptr; 1861 if (TargetRegisterInfo::isPhysicalRegister(MO.getReg())) 1862 return nullptr; 1863 if (MO.isDef() && !MO.isDead()) 1864 return nullptr; 1865 } 1866 bool DontMoveAcrossStores = true; 1867 if (!MI->isSafeToMove(/* AliasAnalysis = */ nullptr, DontMoveAcrossStores)) 1868 return nullptr; 1869 return MI; 1870 } 1871 1872 bool ARMBaseInstrInfo::analyzeSelect(const MachineInstr &MI, 1873 SmallVectorImpl<MachineOperand> &Cond, 1874 unsigned &TrueOp, unsigned &FalseOp, 1875 bool &Optimizable) const { 1876 assert((MI.getOpcode() == ARM::MOVCCr || MI.getOpcode() == ARM::t2MOVCCr) && 1877 "Unknown select instruction"); 1878 // MOVCC operands: 1879 // 0: Def. 1880 // 1: True use. 1881 // 2: False use. 1882 // 3: Condition code. 1883 // 4: CPSR use. 1884 TrueOp = 1; 1885 FalseOp = 2; 1886 Cond.push_back(MI.getOperand(3)); 1887 Cond.push_back(MI.getOperand(4)); 1888 // We can always fold a def. 1889 Optimizable = true; 1890 return false; 1891 } 1892 1893 MachineInstr * 1894 ARMBaseInstrInfo::optimizeSelect(MachineInstr &MI, 1895 SmallPtrSetImpl<MachineInstr *> &SeenMIs, 1896 bool PreferFalse) const { 1897 assert((MI.getOpcode() == ARM::MOVCCr || MI.getOpcode() == ARM::t2MOVCCr) && 1898 "Unknown select instruction"); 1899 MachineRegisterInfo &MRI = MI.getParent()->getParent()->getRegInfo(); 1900 MachineInstr *DefMI = canFoldIntoMOVCC(MI.getOperand(2).getReg(), MRI, this); 1901 bool Invert = !DefMI; 1902 if (!DefMI) 1903 DefMI = canFoldIntoMOVCC(MI.getOperand(1).getReg(), MRI, this); 1904 if (!DefMI) 1905 return nullptr; 1906 1907 // Find new register class to use. 1908 MachineOperand FalseReg = MI.getOperand(Invert ? 2 : 1); 1909 unsigned DestReg = MI.getOperand(0).getReg(); 1910 const TargetRegisterClass *PreviousClass = MRI.getRegClass(FalseReg.getReg()); 1911 if (!MRI.constrainRegClass(DestReg, PreviousClass)) 1912 return nullptr; 1913 1914 // Create a new predicated version of DefMI. 1915 // Rfalse is the first use. 1916 MachineInstrBuilder NewMI = 1917 BuildMI(*MI.getParent(), MI, MI.getDebugLoc(), DefMI->getDesc(), DestReg); 1918 1919 // Copy all the DefMI operands, excluding its (null) predicate. 1920 const MCInstrDesc &DefDesc = DefMI->getDesc(); 1921 for (unsigned i = 1, e = DefDesc.getNumOperands(); 1922 i != e && !DefDesc.OpInfo[i].isPredicate(); ++i) 1923 NewMI.addOperand(DefMI->getOperand(i)); 1924 1925 unsigned CondCode = MI.getOperand(3).getImm(); 1926 if (Invert) 1927 NewMI.addImm(ARMCC::getOppositeCondition(ARMCC::CondCodes(CondCode))); 1928 else 1929 NewMI.addImm(CondCode); 1930 NewMI.addOperand(MI.getOperand(4)); 1931 1932 // DefMI is not the -S version that sets CPSR, so add an optional %noreg. 1933 if (NewMI->hasOptionalDef()) 1934 AddDefaultCC(NewMI); 1935 1936 // The output register value when the predicate is false is an implicit 1937 // register operand tied to the first def. 1938 // The tie makes the register allocator ensure the FalseReg is allocated the 1939 // same register as operand 0. 1940 FalseReg.setImplicit(); 1941 NewMI.addOperand(FalseReg); 1942 NewMI->tieOperands(0, NewMI->getNumOperands() - 1); 1943 1944 // Update SeenMIs set: register newly created MI and erase removed DefMI. 1945 SeenMIs.insert(NewMI); 1946 SeenMIs.erase(DefMI); 1947 1948 // If MI is inside a loop, and DefMI is outside the loop, then kill flags on 1949 // DefMI would be invalid when tranferred inside the loop. Checking for a 1950 // loop is expensive, but at least remove kill flags if they are in different 1951 // BBs. 1952 if (DefMI->getParent() != MI.getParent()) 1953 NewMI->clearKillInfo(); 1954 1955 // The caller will erase MI, but not DefMI. 1956 DefMI->eraseFromParent(); 1957 return NewMI; 1958 } 1959 1960 /// Map pseudo instructions that imply an 'S' bit onto real opcodes. Whether the 1961 /// instruction is encoded with an 'S' bit is determined by the optional CPSR 1962 /// def operand. 1963 /// 1964 /// This will go away once we can teach tblgen how to set the optional CPSR def 1965 /// operand itself. 1966 struct AddSubFlagsOpcodePair { 1967 uint16_t PseudoOpc; 1968 uint16_t MachineOpc; 1969 }; 1970 1971 static const AddSubFlagsOpcodePair AddSubFlagsOpcodeMap[] = { 1972 {ARM::ADDSri, ARM::ADDri}, 1973 {ARM::ADDSrr, ARM::ADDrr}, 1974 {ARM::ADDSrsi, ARM::ADDrsi}, 1975 {ARM::ADDSrsr, ARM::ADDrsr}, 1976 1977 {ARM::SUBSri, ARM::SUBri}, 1978 {ARM::SUBSrr, ARM::SUBrr}, 1979 {ARM::SUBSrsi, ARM::SUBrsi}, 1980 {ARM::SUBSrsr, ARM::SUBrsr}, 1981 1982 {ARM::RSBSri, ARM::RSBri}, 1983 {ARM::RSBSrsi, ARM::RSBrsi}, 1984 {ARM::RSBSrsr, ARM::RSBrsr}, 1985 1986 {ARM::t2ADDSri, ARM::t2ADDri}, 1987 {ARM::t2ADDSrr, ARM::t2ADDrr}, 1988 {ARM::t2ADDSrs, ARM::t2ADDrs}, 1989 1990 {ARM::t2SUBSri, ARM::t2SUBri}, 1991 {ARM::t2SUBSrr, ARM::t2SUBrr}, 1992 {ARM::t2SUBSrs, ARM::t2SUBrs}, 1993 1994 {ARM::t2RSBSri, ARM::t2RSBri}, 1995 {ARM::t2RSBSrs, ARM::t2RSBrs}, 1996 }; 1997 1998 unsigned llvm::convertAddSubFlagsOpcode(unsigned OldOpc) { 1999 for (unsigned i = 0, e = array_lengthof(AddSubFlagsOpcodeMap); i != e; ++i) 2000 if (OldOpc == AddSubFlagsOpcodeMap[i].PseudoOpc) 2001 return AddSubFlagsOpcodeMap[i].MachineOpc; 2002 return 0; 2003 } 2004 2005 void llvm::emitARMRegPlusImmediate(MachineBasicBlock &MBB, 2006 MachineBasicBlock::iterator &MBBI, 2007 const DebugLoc &dl, unsigned DestReg, 2008 unsigned BaseReg, int NumBytes, 2009 ARMCC::CondCodes Pred, unsigned PredReg, 2010 const ARMBaseInstrInfo &TII, 2011 unsigned MIFlags) { 2012 if (NumBytes == 0 && DestReg != BaseReg) { 2013 BuildMI(MBB, MBBI, dl, TII.get(ARM::MOVr), DestReg) 2014 .addReg(BaseReg, RegState::Kill) 2015 .addImm((unsigned)Pred).addReg(PredReg).addReg(0) 2016 .setMIFlags(MIFlags); 2017 return; 2018 } 2019 2020 bool isSub = NumBytes < 0; 2021 if (isSub) NumBytes = -NumBytes; 2022 2023 while (NumBytes) { 2024 unsigned RotAmt = ARM_AM::getSOImmValRotate(NumBytes); 2025 unsigned ThisVal = NumBytes & ARM_AM::rotr32(0xFF, RotAmt); 2026 assert(ThisVal && "Didn't extract field correctly"); 2027 2028 // We will handle these bits from offset, clear them. 2029 NumBytes &= ~ThisVal; 2030 2031 assert(ARM_AM::getSOImmVal(ThisVal) != -1 && "Bit extraction didn't work?"); 2032 2033 // Build the new ADD / SUB. 2034 unsigned Opc = isSub ? ARM::SUBri : ARM::ADDri; 2035 BuildMI(MBB, MBBI, dl, TII.get(Opc), DestReg) 2036 .addReg(BaseReg, RegState::Kill).addImm(ThisVal) 2037 .addImm((unsigned)Pred).addReg(PredReg).addReg(0) 2038 .setMIFlags(MIFlags); 2039 BaseReg = DestReg; 2040 } 2041 } 2042 2043 bool llvm::tryFoldSPUpdateIntoPushPop(const ARMSubtarget &Subtarget, 2044 MachineFunction &MF, MachineInstr *MI, 2045 unsigned NumBytes) { 2046 // This optimisation potentially adds lots of load and store 2047 // micro-operations, it's only really a great benefit to code-size. 2048 if (!MF.getFunction()->optForMinSize()) 2049 return false; 2050 2051 // If only one register is pushed/popped, LLVM can use an LDR/STR 2052 // instead. We can't modify those so make sure we're dealing with an 2053 // instruction we understand. 2054 bool IsPop = isPopOpcode(MI->getOpcode()); 2055 bool IsPush = isPushOpcode(MI->getOpcode()); 2056 if (!IsPush && !IsPop) 2057 return false; 2058 2059 bool IsVFPPushPop = MI->getOpcode() == ARM::VSTMDDB_UPD || 2060 MI->getOpcode() == ARM::VLDMDIA_UPD; 2061 bool IsT1PushPop = MI->getOpcode() == ARM::tPUSH || 2062 MI->getOpcode() == ARM::tPOP || 2063 MI->getOpcode() == ARM::tPOP_RET; 2064 2065 assert((IsT1PushPop || (MI->getOperand(0).getReg() == ARM::SP && 2066 MI->getOperand(1).getReg() == ARM::SP)) && 2067 "trying to fold sp update into non-sp-updating push/pop"); 2068 2069 // The VFP push & pop act on D-registers, so we can only fold an adjustment 2070 // by a multiple of 8 bytes in correctly. Similarly rN is 4-bytes. Don't try 2071 // if this is violated. 2072 if (NumBytes % (IsVFPPushPop ? 8 : 4) != 0) 2073 return false; 2074 2075 // ARM and Thumb2 push/pop insts have explicit "sp, sp" operands (+ 2076 // pred) so the list starts at 4. Thumb1 starts after the predicate. 2077 int RegListIdx = IsT1PushPop ? 2 : 4; 2078 2079 // Calculate the space we'll need in terms of registers. 2080 unsigned FirstReg = MI->getOperand(RegListIdx).getReg(); 2081 unsigned RD0Reg, RegsNeeded; 2082 if (IsVFPPushPop) { 2083 RD0Reg = ARM::D0; 2084 RegsNeeded = NumBytes / 8; 2085 } else { 2086 RD0Reg = ARM::R0; 2087 RegsNeeded = NumBytes / 4; 2088 } 2089 2090 // We're going to have to strip all list operands off before 2091 // re-adding them since the order matters, so save the existing ones 2092 // for later. 2093 SmallVector<MachineOperand, 4> RegList; 2094 for (int i = MI->getNumOperands() - 1; i >= RegListIdx; --i) 2095 RegList.push_back(MI->getOperand(i)); 2096 2097 const TargetRegisterInfo *TRI = MF.getRegInfo().getTargetRegisterInfo(); 2098 const MCPhysReg *CSRegs = TRI->getCalleeSavedRegs(&MF); 2099 2100 // Now try to find enough space in the reglist to allocate NumBytes. 2101 for (unsigned CurReg = FirstReg - 1; CurReg >= RD0Reg && RegsNeeded; 2102 --CurReg) { 2103 if (!IsPop) { 2104 // Pushing any register is completely harmless, mark the 2105 // register involved as undef since we don't care about it in 2106 // the slightest. 2107 RegList.push_back(MachineOperand::CreateReg(CurReg, false, false, 2108 false, false, true)); 2109 --RegsNeeded; 2110 continue; 2111 } 2112 2113 // However, we can only pop an extra register if it's not live. For 2114 // registers live within the function we might clobber a return value 2115 // register; the other way a register can be live here is if it's 2116 // callee-saved. 2117 if (isCalleeSavedRegister(CurReg, CSRegs) || 2118 MI->getParent()->computeRegisterLiveness(TRI, CurReg, MI) != 2119 MachineBasicBlock::LQR_Dead) { 2120 // VFP pops don't allow holes in the register list, so any skip is fatal 2121 // for our transformation. GPR pops do, so we should just keep looking. 2122 if (IsVFPPushPop) 2123 return false; 2124 else 2125 continue; 2126 } 2127 2128 // Mark the unimportant registers as <def,dead> in the POP. 2129 RegList.push_back(MachineOperand::CreateReg(CurReg, true, false, false, 2130 true)); 2131 --RegsNeeded; 2132 } 2133 2134 if (RegsNeeded > 0) 2135 return false; 2136 2137 // Finally we know we can profitably perform the optimisation so go 2138 // ahead: strip all existing registers off and add them back again 2139 // in the right order. 2140 for (int i = MI->getNumOperands() - 1; i >= RegListIdx; --i) 2141 MI->RemoveOperand(i); 2142 2143 // Add the complete list back in. 2144 MachineInstrBuilder MIB(MF, &*MI); 2145 for (int i = RegList.size() - 1; i >= 0; --i) 2146 MIB.addOperand(RegList[i]); 2147 2148 return true; 2149 } 2150 2151 bool llvm::rewriteARMFrameIndex(MachineInstr &MI, unsigned FrameRegIdx, 2152 unsigned FrameReg, int &Offset, 2153 const ARMBaseInstrInfo &TII) { 2154 unsigned Opcode = MI.getOpcode(); 2155 const MCInstrDesc &Desc = MI.getDesc(); 2156 unsigned AddrMode = (Desc.TSFlags & ARMII::AddrModeMask); 2157 bool isSub = false; 2158 2159 // Memory operands in inline assembly always use AddrMode2. 2160 if (Opcode == ARM::INLINEASM) 2161 AddrMode = ARMII::AddrMode2; 2162 2163 if (Opcode == ARM::ADDri) { 2164 Offset += MI.getOperand(FrameRegIdx+1).getImm(); 2165 if (Offset == 0) { 2166 // Turn it into a move. 2167 MI.setDesc(TII.get(ARM::MOVr)); 2168 MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false); 2169 MI.RemoveOperand(FrameRegIdx+1); 2170 Offset = 0; 2171 return true; 2172 } else if (Offset < 0) { 2173 Offset = -Offset; 2174 isSub = true; 2175 MI.setDesc(TII.get(ARM::SUBri)); 2176 } 2177 2178 // Common case: small offset, fits into instruction. 2179 if (ARM_AM::getSOImmVal(Offset) != -1) { 2180 // Replace the FrameIndex with sp / fp 2181 MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false); 2182 MI.getOperand(FrameRegIdx+1).ChangeToImmediate(Offset); 2183 Offset = 0; 2184 return true; 2185 } 2186 2187 // Otherwise, pull as much of the immedidate into this ADDri/SUBri 2188 // as possible. 2189 unsigned RotAmt = ARM_AM::getSOImmValRotate(Offset); 2190 unsigned ThisImmVal = Offset & ARM_AM::rotr32(0xFF, RotAmt); 2191 2192 // We will handle these bits from offset, clear them. 2193 Offset &= ~ThisImmVal; 2194 2195 // Get the properly encoded SOImmVal field. 2196 assert(ARM_AM::getSOImmVal(ThisImmVal) != -1 && 2197 "Bit extraction didn't work?"); 2198 MI.getOperand(FrameRegIdx+1).ChangeToImmediate(ThisImmVal); 2199 } else { 2200 unsigned ImmIdx = 0; 2201 int InstrOffs = 0; 2202 unsigned NumBits = 0; 2203 unsigned Scale = 1; 2204 switch (AddrMode) { 2205 case ARMII::AddrMode_i12: { 2206 ImmIdx = FrameRegIdx + 1; 2207 InstrOffs = MI.getOperand(ImmIdx).getImm(); 2208 NumBits = 12; 2209 break; 2210 } 2211 case ARMII::AddrMode2: { 2212 ImmIdx = FrameRegIdx+2; 2213 InstrOffs = ARM_AM::getAM2Offset(MI.getOperand(ImmIdx).getImm()); 2214 if (ARM_AM::getAM2Op(MI.getOperand(ImmIdx).getImm()) == ARM_AM::sub) 2215 InstrOffs *= -1; 2216 NumBits = 12; 2217 break; 2218 } 2219 case ARMII::AddrMode3: { 2220 ImmIdx = FrameRegIdx+2; 2221 InstrOffs = ARM_AM::getAM3Offset(MI.getOperand(ImmIdx).getImm()); 2222 if (ARM_AM::getAM3Op(MI.getOperand(ImmIdx).getImm()) == ARM_AM::sub) 2223 InstrOffs *= -1; 2224 NumBits = 8; 2225 break; 2226 } 2227 case ARMII::AddrMode4: 2228 case ARMII::AddrMode6: 2229 // Can't fold any offset even if it's zero. 2230 return false; 2231 case ARMII::AddrMode5: { 2232 ImmIdx = FrameRegIdx+1; 2233 InstrOffs = ARM_AM::getAM5Offset(MI.getOperand(ImmIdx).getImm()); 2234 if (ARM_AM::getAM5Op(MI.getOperand(ImmIdx).getImm()) == ARM_AM::sub) 2235 InstrOffs *= -1; 2236 NumBits = 8; 2237 Scale = 4; 2238 break; 2239 } 2240 default: 2241 llvm_unreachable("Unsupported addressing mode!"); 2242 } 2243 2244 Offset += InstrOffs * Scale; 2245 assert((Offset & (Scale-1)) == 0 && "Can't encode this offset!"); 2246 if (Offset < 0) { 2247 Offset = -Offset; 2248 isSub = true; 2249 } 2250 2251 // Attempt to fold address comp. if opcode has offset bits 2252 if (NumBits > 0) { 2253 // Common case: small offset, fits into instruction. 2254 MachineOperand &ImmOp = MI.getOperand(ImmIdx); 2255 int ImmedOffset = Offset / Scale; 2256 unsigned Mask = (1 << NumBits) - 1; 2257 if ((unsigned)Offset <= Mask * Scale) { 2258 // Replace the FrameIndex with sp 2259 MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false); 2260 // FIXME: When addrmode2 goes away, this will simplify (like the 2261 // T2 version), as the LDR.i12 versions don't need the encoding 2262 // tricks for the offset value. 2263 if (isSub) { 2264 if (AddrMode == ARMII::AddrMode_i12) 2265 ImmedOffset = -ImmedOffset; 2266 else 2267 ImmedOffset |= 1 << NumBits; 2268 } 2269 ImmOp.ChangeToImmediate(ImmedOffset); 2270 Offset = 0; 2271 return true; 2272 } 2273 2274 // Otherwise, it didn't fit. Pull in what we can to simplify the immed. 2275 ImmedOffset = ImmedOffset & Mask; 2276 if (isSub) { 2277 if (AddrMode == ARMII::AddrMode_i12) 2278 ImmedOffset = -ImmedOffset; 2279 else 2280 ImmedOffset |= 1 << NumBits; 2281 } 2282 ImmOp.ChangeToImmediate(ImmedOffset); 2283 Offset &= ~(Mask*Scale); 2284 } 2285 } 2286 2287 Offset = (isSub) ? -Offset : Offset; 2288 return Offset == 0; 2289 } 2290 2291 /// analyzeCompare - For a comparison instruction, return the source registers 2292 /// in SrcReg and SrcReg2 if having two register operands, and the value it 2293 /// compares against in CmpValue. Return true if the comparison instruction 2294 /// can be analyzed. 2295 bool ARMBaseInstrInfo::analyzeCompare(const MachineInstr &MI, unsigned &SrcReg, 2296 unsigned &SrcReg2, int &CmpMask, 2297 int &CmpValue) const { 2298 switch (MI.getOpcode()) { 2299 default: break; 2300 case ARM::CMPri: 2301 case ARM::t2CMPri: 2302 case ARM::tCMPi8: 2303 SrcReg = MI.getOperand(0).getReg(); 2304 SrcReg2 = 0; 2305 CmpMask = ~0; 2306 CmpValue = MI.getOperand(1).getImm(); 2307 return true; 2308 case ARM::CMPrr: 2309 case ARM::t2CMPrr: 2310 SrcReg = MI.getOperand(0).getReg(); 2311 SrcReg2 = MI.getOperand(1).getReg(); 2312 CmpMask = ~0; 2313 CmpValue = 0; 2314 return true; 2315 case ARM::TSTri: 2316 case ARM::t2TSTri: 2317 SrcReg = MI.getOperand(0).getReg(); 2318 SrcReg2 = 0; 2319 CmpMask = MI.getOperand(1).getImm(); 2320 CmpValue = 0; 2321 return true; 2322 } 2323 2324 return false; 2325 } 2326 2327 /// isSuitableForMask - Identify a suitable 'and' instruction that 2328 /// operates on the given source register and applies the same mask 2329 /// as a 'tst' instruction. Provide a limited look-through for copies. 2330 /// When successful, MI will hold the found instruction. 2331 static bool isSuitableForMask(MachineInstr *&MI, unsigned SrcReg, 2332 int CmpMask, bool CommonUse) { 2333 switch (MI->getOpcode()) { 2334 case ARM::ANDri: 2335 case ARM::t2ANDri: 2336 if (CmpMask != MI->getOperand(2).getImm()) 2337 return false; 2338 if (SrcReg == MI->getOperand(CommonUse ? 1 : 0).getReg()) 2339 return true; 2340 break; 2341 } 2342 2343 return false; 2344 } 2345 2346 /// getSwappedCondition - assume the flags are set by MI(a,b), return 2347 /// the condition code if we modify the instructions such that flags are 2348 /// set by MI(b,a). 2349 inline static ARMCC::CondCodes getSwappedCondition(ARMCC::CondCodes CC) { 2350 switch (CC) { 2351 default: return ARMCC::AL; 2352 case ARMCC::EQ: return ARMCC::EQ; 2353 case ARMCC::NE: return ARMCC::NE; 2354 case ARMCC::HS: return ARMCC::LS; 2355 case ARMCC::LO: return ARMCC::HI; 2356 case ARMCC::HI: return ARMCC::LO; 2357 case ARMCC::LS: return ARMCC::HS; 2358 case ARMCC::GE: return ARMCC::LE; 2359 case ARMCC::LT: return ARMCC::GT; 2360 case ARMCC::GT: return ARMCC::LT; 2361 case ARMCC::LE: return ARMCC::GE; 2362 } 2363 } 2364 2365 /// isRedundantFlagInstr - check whether the first instruction, whose only 2366 /// purpose is to update flags, can be made redundant. 2367 /// CMPrr can be made redundant by SUBrr if the operands are the same. 2368 /// CMPri can be made redundant by SUBri if the operands are the same. 2369 /// This function can be extended later on. 2370 inline static bool isRedundantFlagInstr(MachineInstr *CmpI, unsigned SrcReg, 2371 unsigned SrcReg2, int ImmValue, 2372 MachineInstr *OI) { 2373 if ((CmpI->getOpcode() == ARM::CMPrr || 2374 CmpI->getOpcode() == ARM::t2CMPrr) && 2375 (OI->getOpcode() == ARM::SUBrr || 2376 OI->getOpcode() == ARM::t2SUBrr) && 2377 ((OI->getOperand(1).getReg() == SrcReg && 2378 OI->getOperand(2).getReg() == SrcReg2) || 2379 (OI->getOperand(1).getReg() == SrcReg2 && 2380 OI->getOperand(2).getReg() == SrcReg))) 2381 return true; 2382 2383 if ((CmpI->getOpcode() == ARM::CMPri || 2384 CmpI->getOpcode() == ARM::t2CMPri) && 2385 (OI->getOpcode() == ARM::SUBri || 2386 OI->getOpcode() == ARM::t2SUBri) && 2387 OI->getOperand(1).getReg() == SrcReg && 2388 OI->getOperand(2).getImm() == ImmValue) 2389 return true; 2390 return false; 2391 } 2392 2393 /// optimizeCompareInstr - Convert the instruction supplying the argument to the 2394 /// comparison into one that sets the zero bit in the flags register; 2395 /// Remove a redundant Compare instruction if an earlier instruction can set the 2396 /// flags in the same way as Compare. 2397 /// E.g. SUBrr(r1,r2) and CMPrr(r1,r2). We also handle the case where two 2398 /// operands are swapped: SUBrr(r1,r2) and CMPrr(r2,r1), by updating the 2399 /// condition code of instructions which use the flags. 2400 bool ARMBaseInstrInfo::optimizeCompareInstr( 2401 MachineInstr &CmpInstr, unsigned SrcReg, unsigned SrcReg2, int CmpMask, 2402 int CmpValue, const MachineRegisterInfo *MRI) const { 2403 // Get the unique definition of SrcReg. 2404 MachineInstr *MI = MRI->getUniqueVRegDef(SrcReg); 2405 if (!MI) return false; 2406 2407 // Masked compares sometimes use the same register as the corresponding 'and'. 2408 if (CmpMask != ~0) { 2409 if (!isSuitableForMask(MI, SrcReg, CmpMask, false) || isPredicated(*MI)) { 2410 MI = nullptr; 2411 for (MachineRegisterInfo::use_instr_iterator 2412 UI = MRI->use_instr_begin(SrcReg), UE = MRI->use_instr_end(); 2413 UI != UE; ++UI) { 2414 if (UI->getParent() != CmpInstr.getParent()) 2415 continue; 2416 MachineInstr *PotentialAND = &*UI; 2417 if (!isSuitableForMask(PotentialAND, SrcReg, CmpMask, true) || 2418 isPredicated(*PotentialAND)) 2419 continue; 2420 MI = PotentialAND; 2421 break; 2422 } 2423 if (!MI) return false; 2424 } 2425 } 2426 2427 // Get ready to iterate backward from CmpInstr. 2428 MachineBasicBlock::iterator I = CmpInstr, E = MI, 2429 B = CmpInstr.getParent()->begin(); 2430 2431 // Early exit if CmpInstr is at the beginning of the BB. 2432 if (I == B) return false; 2433 2434 // There are two possible candidates which can be changed to set CPSR: 2435 // One is MI, the other is a SUB instruction. 2436 // For CMPrr(r1,r2), we are looking for SUB(r1,r2) or SUB(r2,r1). 2437 // For CMPri(r1, CmpValue), we are looking for SUBri(r1, CmpValue). 2438 MachineInstr *Sub = nullptr; 2439 if (SrcReg2 != 0) 2440 // MI is not a candidate for CMPrr. 2441 MI = nullptr; 2442 else if (MI->getParent() != CmpInstr.getParent() || CmpValue != 0) { 2443 // Conservatively refuse to convert an instruction which isn't in the same 2444 // BB as the comparison. 2445 // For CMPri w/ CmpValue != 0, a Sub may still be a candidate. 2446 // Thus we cannot return here. 2447 if (CmpInstr.getOpcode() == ARM::CMPri || 2448 CmpInstr.getOpcode() == ARM::t2CMPri) 2449 MI = nullptr; 2450 else 2451 return false; 2452 } 2453 2454 // Check that CPSR isn't set between the comparison instruction and the one we 2455 // want to change. At the same time, search for Sub. 2456 const TargetRegisterInfo *TRI = &getRegisterInfo(); 2457 --I; 2458 for (; I != E; --I) { 2459 const MachineInstr &Instr = *I; 2460 2461 if (Instr.modifiesRegister(ARM::CPSR, TRI) || 2462 Instr.readsRegister(ARM::CPSR, TRI)) 2463 // This instruction modifies or uses CPSR after the one we want to 2464 // change. We can't do this transformation. 2465 return false; 2466 2467 // Check whether CmpInstr can be made redundant by the current instruction. 2468 if (isRedundantFlagInstr(&CmpInstr, SrcReg, SrcReg2, CmpValue, &*I)) { 2469 Sub = &*I; 2470 break; 2471 } 2472 2473 if (I == B) 2474 // The 'and' is below the comparison instruction. 2475 return false; 2476 } 2477 2478 // Return false if no candidates exist. 2479 if (!MI && !Sub) 2480 return false; 2481 2482 // The single candidate is called MI. 2483 if (!MI) MI = Sub; 2484 2485 // We can't use a predicated instruction - it doesn't always write the flags. 2486 if (isPredicated(*MI)) 2487 return false; 2488 2489 bool IsThumb1 = false; 2490 switch (MI->getOpcode()) { 2491 default: break; 2492 case ARM::tLSLri: 2493 case ARM::tLSRri: 2494 case ARM::tLSLrr: 2495 case ARM::tLSRrr: 2496 case ARM::tSUBrr: 2497 case ARM::tADDrr: 2498 case ARM::tADDi3: 2499 case ARM::tADDi8: 2500 case ARM::tSUBi3: 2501 case ARM::tSUBi8: 2502 IsThumb1 = true; 2503 LLVM_FALLTHROUGH; 2504 case ARM::RSBrr: 2505 case ARM::RSBri: 2506 case ARM::RSCrr: 2507 case ARM::RSCri: 2508 case ARM::ADDrr: 2509 case ARM::ADDri: 2510 case ARM::ADCrr: 2511 case ARM::ADCri: 2512 case ARM::SUBrr: 2513 case ARM::SUBri: 2514 case ARM::SBCrr: 2515 case ARM::SBCri: 2516 case ARM::t2RSBri: 2517 case ARM::t2ADDrr: 2518 case ARM::t2ADDri: 2519 case ARM::t2ADCrr: 2520 case ARM::t2ADCri: 2521 case ARM::t2SUBrr: 2522 case ARM::t2SUBri: 2523 case ARM::t2SBCrr: 2524 case ARM::t2SBCri: 2525 case ARM::ANDrr: 2526 case ARM::ANDri: 2527 case ARM::t2ANDrr: 2528 case ARM::t2ANDri: 2529 case ARM::ORRrr: 2530 case ARM::ORRri: 2531 case ARM::t2ORRrr: 2532 case ARM::t2ORRri: 2533 case ARM::EORrr: 2534 case ARM::EORri: 2535 case ARM::t2EORrr: 2536 case ARM::t2EORri: { 2537 // Scan forward for the use of CPSR 2538 // When checking against MI: if it's a conditional code that requires 2539 // checking of the V bit or C bit, then this is not safe to do. 2540 // It is safe to remove CmpInstr if CPSR is redefined or killed. 2541 // If we are done with the basic block, we need to check whether CPSR is 2542 // live-out. 2543 SmallVector<std::pair<MachineOperand*, ARMCC::CondCodes>, 4> 2544 OperandsToUpdate; 2545 bool isSafe = false; 2546 I = CmpInstr; 2547 E = CmpInstr.getParent()->end(); 2548 while (!isSafe && ++I != E) { 2549 const MachineInstr &Instr = *I; 2550 for (unsigned IO = 0, EO = Instr.getNumOperands(); 2551 !isSafe && IO != EO; ++IO) { 2552 const MachineOperand &MO = Instr.getOperand(IO); 2553 if (MO.isRegMask() && MO.clobbersPhysReg(ARM::CPSR)) { 2554 isSafe = true; 2555 break; 2556 } 2557 if (!MO.isReg() || MO.getReg() != ARM::CPSR) 2558 continue; 2559 if (MO.isDef()) { 2560 isSafe = true; 2561 break; 2562 } 2563 // Condition code is after the operand before CPSR except for VSELs. 2564 ARMCC::CondCodes CC; 2565 bool IsInstrVSel = true; 2566 switch (Instr.getOpcode()) { 2567 default: 2568 IsInstrVSel = false; 2569 CC = (ARMCC::CondCodes)Instr.getOperand(IO - 1).getImm(); 2570 break; 2571 case ARM::VSELEQD: 2572 case ARM::VSELEQS: 2573 CC = ARMCC::EQ; 2574 break; 2575 case ARM::VSELGTD: 2576 case ARM::VSELGTS: 2577 CC = ARMCC::GT; 2578 break; 2579 case ARM::VSELGED: 2580 case ARM::VSELGES: 2581 CC = ARMCC::GE; 2582 break; 2583 case ARM::VSELVSS: 2584 case ARM::VSELVSD: 2585 CC = ARMCC::VS; 2586 break; 2587 } 2588 2589 if (Sub) { 2590 ARMCC::CondCodes NewCC = getSwappedCondition(CC); 2591 if (NewCC == ARMCC::AL) 2592 return false; 2593 // If we have SUB(r1, r2) and CMP(r2, r1), the condition code based 2594 // on CMP needs to be updated to be based on SUB. 2595 // Push the condition code operands to OperandsToUpdate. 2596 // If it is safe to remove CmpInstr, the condition code of these 2597 // operands will be modified. 2598 if (SrcReg2 != 0 && Sub->getOperand(1).getReg() == SrcReg2 && 2599 Sub->getOperand(2).getReg() == SrcReg) { 2600 // VSel doesn't support condition code update. 2601 if (IsInstrVSel) 2602 return false; 2603 OperandsToUpdate.push_back( 2604 std::make_pair(&((*I).getOperand(IO - 1)), NewCC)); 2605 } 2606 } else { 2607 // No Sub, so this is x = <op> y, z; cmp x, 0. 2608 switch (CC) { 2609 case ARMCC::EQ: // Z 2610 case ARMCC::NE: // Z 2611 case ARMCC::MI: // N 2612 case ARMCC::PL: // N 2613 case ARMCC::AL: // none 2614 // CPSR can be used multiple times, we should continue. 2615 break; 2616 case ARMCC::HS: // C 2617 case ARMCC::LO: // C 2618 case ARMCC::VS: // V 2619 case ARMCC::VC: // V 2620 case ARMCC::HI: // C Z 2621 case ARMCC::LS: // C Z 2622 case ARMCC::GE: // N V 2623 case ARMCC::LT: // N V 2624 case ARMCC::GT: // Z N V 2625 case ARMCC::LE: // Z N V 2626 // The instruction uses the V bit or C bit which is not safe. 2627 return false; 2628 } 2629 } 2630 } 2631 } 2632 2633 // If CPSR is not killed nor re-defined, we should check whether it is 2634 // live-out. If it is live-out, do not optimize. 2635 if (!isSafe) { 2636 MachineBasicBlock *MBB = CmpInstr.getParent(); 2637 for (MachineBasicBlock::succ_iterator SI = MBB->succ_begin(), 2638 SE = MBB->succ_end(); SI != SE; ++SI) 2639 if ((*SI)->isLiveIn(ARM::CPSR)) 2640 return false; 2641 } 2642 2643 // Toggle the optional operand to CPSR (if it exists - in Thumb1 we always 2644 // set CPSR so this is represented as an explicit output) 2645 if (!IsThumb1) { 2646 MI->getOperand(5).setReg(ARM::CPSR); 2647 MI->getOperand(5).setIsDef(true); 2648 } 2649 assert(!isPredicated(*MI) && "Can't use flags from predicated instruction"); 2650 CmpInstr.eraseFromParent(); 2651 2652 // Modify the condition code of operands in OperandsToUpdate. 2653 // Since we have SUB(r1, r2) and CMP(r2, r1), the condition code needs to 2654 // be changed from r2 > r1 to r1 < r2, from r2 < r1 to r1 > r2, etc. 2655 for (unsigned i = 0, e = OperandsToUpdate.size(); i < e; i++) 2656 OperandsToUpdate[i].first->setImm(OperandsToUpdate[i].second); 2657 return true; 2658 } 2659 } 2660 2661 return false; 2662 } 2663 2664 bool ARMBaseInstrInfo::FoldImmediate(MachineInstr &UseMI, MachineInstr &DefMI, 2665 unsigned Reg, 2666 MachineRegisterInfo *MRI) const { 2667 // Fold large immediates into add, sub, or, xor. 2668 unsigned DefOpc = DefMI.getOpcode(); 2669 if (DefOpc != ARM::t2MOVi32imm && DefOpc != ARM::MOVi32imm) 2670 return false; 2671 if (!DefMI.getOperand(1).isImm()) 2672 // Could be t2MOVi32imm <ga:xx> 2673 return false; 2674 2675 if (!MRI->hasOneNonDBGUse(Reg)) 2676 return false; 2677 2678 const MCInstrDesc &DefMCID = DefMI.getDesc(); 2679 if (DefMCID.hasOptionalDef()) { 2680 unsigned NumOps = DefMCID.getNumOperands(); 2681 const MachineOperand &MO = DefMI.getOperand(NumOps - 1); 2682 if (MO.getReg() == ARM::CPSR && !MO.isDead()) 2683 // If DefMI defines CPSR and it is not dead, it's obviously not safe 2684 // to delete DefMI. 2685 return false; 2686 } 2687 2688 const MCInstrDesc &UseMCID = UseMI.getDesc(); 2689 if (UseMCID.hasOptionalDef()) { 2690 unsigned NumOps = UseMCID.getNumOperands(); 2691 if (UseMI.getOperand(NumOps - 1).getReg() == ARM::CPSR) 2692 // If the instruction sets the flag, do not attempt this optimization 2693 // since it may change the semantics of the code. 2694 return false; 2695 } 2696 2697 unsigned UseOpc = UseMI.getOpcode(); 2698 unsigned NewUseOpc = 0; 2699 uint32_t ImmVal = (uint32_t)DefMI.getOperand(1).getImm(); 2700 uint32_t SOImmValV1 = 0, SOImmValV2 = 0; 2701 bool Commute = false; 2702 switch (UseOpc) { 2703 default: return false; 2704 case ARM::SUBrr: 2705 case ARM::ADDrr: 2706 case ARM::ORRrr: 2707 case ARM::EORrr: 2708 case ARM::t2SUBrr: 2709 case ARM::t2ADDrr: 2710 case ARM::t2ORRrr: 2711 case ARM::t2EORrr: { 2712 Commute = UseMI.getOperand(2).getReg() != Reg; 2713 switch (UseOpc) { 2714 default: break; 2715 case ARM::ADDrr: 2716 case ARM::SUBrr: { 2717 if (UseOpc == ARM::SUBrr && Commute) 2718 return false; 2719 2720 // ADD/SUB are special because they're essentially the same operation, so 2721 // we can handle a larger range of immediates. 2722 if (ARM_AM::isSOImmTwoPartVal(ImmVal)) 2723 NewUseOpc = UseOpc == ARM::ADDrr ? ARM::ADDri : ARM::SUBri; 2724 else if (ARM_AM::isSOImmTwoPartVal(-ImmVal)) { 2725 ImmVal = -ImmVal; 2726 NewUseOpc = UseOpc == ARM::ADDrr ? ARM::SUBri : ARM::ADDri; 2727 } else 2728 return false; 2729 SOImmValV1 = (uint32_t)ARM_AM::getSOImmTwoPartFirst(ImmVal); 2730 SOImmValV2 = (uint32_t)ARM_AM::getSOImmTwoPartSecond(ImmVal); 2731 break; 2732 } 2733 case ARM::ORRrr: 2734 case ARM::EORrr: { 2735 if (!ARM_AM::isSOImmTwoPartVal(ImmVal)) 2736 return false; 2737 SOImmValV1 = (uint32_t)ARM_AM::getSOImmTwoPartFirst(ImmVal); 2738 SOImmValV2 = (uint32_t)ARM_AM::getSOImmTwoPartSecond(ImmVal); 2739 switch (UseOpc) { 2740 default: break; 2741 case ARM::ORRrr: NewUseOpc = ARM::ORRri; break; 2742 case ARM::EORrr: NewUseOpc = ARM::EORri; break; 2743 } 2744 break; 2745 } 2746 case ARM::t2ADDrr: 2747 case ARM::t2SUBrr: { 2748 if (UseOpc == ARM::t2SUBrr && Commute) 2749 return false; 2750 2751 // ADD/SUB are special because they're essentially the same operation, so 2752 // we can handle a larger range of immediates. 2753 if (ARM_AM::isT2SOImmTwoPartVal(ImmVal)) 2754 NewUseOpc = UseOpc == ARM::t2ADDrr ? ARM::t2ADDri : ARM::t2SUBri; 2755 else if (ARM_AM::isT2SOImmTwoPartVal(-ImmVal)) { 2756 ImmVal = -ImmVal; 2757 NewUseOpc = UseOpc == ARM::t2ADDrr ? ARM::t2SUBri : ARM::t2ADDri; 2758 } else 2759 return false; 2760 SOImmValV1 = (uint32_t)ARM_AM::getT2SOImmTwoPartFirst(ImmVal); 2761 SOImmValV2 = (uint32_t)ARM_AM::getT2SOImmTwoPartSecond(ImmVal); 2762 break; 2763 } 2764 case ARM::t2ORRrr: 2765 case ARM::t2EORrr: { 2766 if (!ARM_AM::isT2SOImmTwoPartVal(ImmVal)) 2767 return false; 2768 SOImmValV1 = (uint32_t)ARM_AM::getT2SOImmTwoPartFirst(ImmVal); 2769 SOImmValV2 = (uint32_t)ARM_AM::getT2SOImmTwoPartSecond(ImmVal); 2770 switch (UseOpc) { 2771 default: break; 2772 case ARM::t2ORRrr: NewUseOpc = ARM::t2ORRri; break; 2773 case ARM::t2EORrr: NewUseOpc = ARM::t2EORri; break; 2774 } 2775 break; 2776 } 2777 } 2778 } 2779 } 2780 2781 unsigned OpIdx = Commute ? 2 : 1; 2782 unsigned Reg1 = UseMI.getOperand(OpIdx).getReg(); 2783 bool isKill = UseMI.getOperand(OpIdx).isKill(); 2784 unsigned NewReg = MRI->createVirtualRegister(MRI->getRegClass(Reg)); 2785 AddDefaultCC( 2786 AddDefaultPred(BuildMI(*UseMI.getParent(), UseMI, UseMI.getDebugLoc(), 2787 get(NewUseOpc), NewReg) 2788 .addReg(Reg1, getKillRegState(isKill)) 2789 .addImm(SOImmValV1))); 2790 UseMI.setDesc(get(NewUseOpc)); 2791 UseMI.getOperand(1).setReg(NewReg); 2792 UseMI.getOperand(1).setIsKill(); 2793 UseMI.getOperand(2).ChangeToImmediate(SOImmValV2); 2794 DefMI.eraseFromParent(); 2795 return true; 2796 } 2797 2798 static unsigned getNumMicroOpsSwiftLdSt(const InstrItineraryData *ItinData, 2799 const MachineInstr &MI) { 2800 switch (MI.getOpcode()) { 2801 default: { 2802 const MCInstrDesc &Desc = MI.getDesc(); 2803 int UOps = ItinData->getNumMicroOps(Desc.getSchedClass()); 2804 assert(UOps >= 0 && "bad # UOps"); 2805 return UOps; 2806 } 2807 2808 case ARM::LDRrs: 2809 case ARM::LDRBrs: 2810 case ARM::STRrs: 2811 case ARM::STRBrs: { 2812 unsigned ShOpVal = MI.getOperand(3).getImm(); 2813 bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub; 2814 unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); 2815 if (!isSub && 2816 (ShImm == 0 || 2817 ((ShImm == 1 || ShImm == 2 || ShImm == 3) && 2818 ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl))) 2819 return 1; 2820 return 2; 2821 } 2822 2823 case ARM::LDRH: 2824 case ARM::STRH: { 2825 if (!MI.getOperand(2).getReg()) 2826 return 1; 2827 2828 unsigned ShOpVal = MI.getOperand(3).getImm(); 2829 bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub; 2830 unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); 2831 if (!isSub && 2832 (ShImm == 0 || 2833 ((ShImm == 1 || ShImm == 2 || ShImm == 3) && 2834 ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl))) 2835 return 1; 2836 return 2; 2837 } 2838 2839 case ARM::LDRSB: 2840 case ARM::LDRSH: 2841 return (ARM_AM::getAM3Op(MI.getOperand(3).getImm()) == ARM_AM::sub) ? 3 : 2; 2842 2843 case ARM::LDRSB_POST: 2844 case ARM::LDRSH_POST: { 2845 unsigned Rt = MI.getOperand(0).getReg(); 2846 unsigned Rm = MI.getOperand(3).getReg(); 2847 return (Rt == Rm) ? 4 : 3; 2848 } 2849 2850 case ARM::LDR_PRE_REG: 2851 case ARM::LDRB_PRE_REG: { 2852 unsigned Rt = MI.getOperand(0).getReg(); 2853 unsigned Rm = MI.getOperand(3).getReg(); 2854 if (Rt == Rm) 2855 return 3; 2856 unsigned ShOpVal = MI.getOperand(4).getImm(); 2857 bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub; 2858 unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); 2859 if (!isSub && 2860 (ShImm == 0 || 2861 ((ShImm == 1 || ShImm == 2 || ShImm == 3) && 2862 ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl))) 2863 return 2; 2864 return 3; 2865 } 2866 2867 case ARM::STR_PRE_REG: 2868 case ARM::STRB_PRE_REG: { 2869 unsigned ShOpVal = MI.getOperand(4).getImm(); 2870 bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub; 2871 unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); 2872 if (!isSub && 2873 (ShImm == 0 || 2874 ((ShImm == 1 || ShImm == 2 || ShImm == 3) && 2875 ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl))) 2876 return 2; 2877 return 3; 2878 } 2879 2880 case ARM::LDRH_PRE: 2881 case ARM::STRH_PRE: { 2882 unsigned Rt = MI.getOperand(0).getReg(); 2883 unsigned Rm = MI.getOperand(3).getReg(); 2884 if (!Rm) 2885 return 2; 2886 if (Rt == Rm) 2887 return 3; 2888 return (ARM_AM::getAM3Op(MI.getOperand(4).getImm()) == ARM_AM::sub) ? 3 : 2; 2889 } 2890 2891 case ARM::LDR_POST_REG: 2892 case ARM::LDRB_POST_REG: 2893 case ARM::LDRH_POST: { 2894 unsigned Rt = MI.getOperand(0).getReg(); 2895 unsigned Rm = MI.getOperand(3).getReg(); 2896 return (Rt == Rm) ? 3 : 2; 2897 } 2898 2899 case ARM::LDR_PRE_IMM: 2900 case ARM::LDRB_PRE_IMM: 2901 case ARM::LDR_POST_IMM: 2902 case ARM::LDRB_POST_IMM: 2903 case ARM::STRB_POST_IMM: 2904 case ARM::STRB_POST_REG: 2905 case ARM::STRB_PRE_IMM: 2906 case ARM::STRH_POST: 2907 case ARM::STR_POST_IMM: 2908 case ARM::STR_POST_REG: 2909 case ARM::STR_PRE_IMM: 2910 return 2; 2911 2912 case ARM::LDRSB_PRE: 2913 case ARM::LDRSH_PRE: { 2914 unsigned Rm = MI.getOperand(3).getReg(); 2915 if (Rm == 0) 2916 return 3; 2917 unsigned Rt = MI.getOperand(0).getReg(); 2918 if (Rt == Rm) 2919 return 4; 2920 unsigned ShOpVal = MI.getOperand(4).getImm(); 2921 bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub; 2922 unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); 2923 if (!isSub && 2924 (ShImm == 0 || 2925 ((ShImm == 1 || ShImm == 2 || ShImm == 3) && 2926 ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl))) 2927 return 3; 2928 return 4; 2929 } 2930 2931 case ARM::LDRD: { 2932 unsigned Rt = MI.getOperand(0).getReg(); 2933 unsigned Rn = MI.getOperand(2).getReg(); 2934 unsigned Rm = MI.getOperand(3).getReg(); 2935 if (Rm) 2936 return (ARM_AM::getAM3Op(MI.getOperand(4).getImm()) == ARM_AM::sub) ? 4 2937 : 3; 2938 return (Rt == Rn) ? 3 : 2; 2939 } 2940 2941 case ARM::STRD: { 2942 unsigned Rm = MI.getOperand(3).getReg(); 2943 if (Rm) 2944 return (ARM_AM::getAM3Op(MI.getOperand(4).getImm()) == ARM_AM::sub) ? 4 2945 : 3; 2946 return 2; 2947 } 2948 2949 case ARM::LDRD_POST: 2950 case ARM::t2LDRD_POST: 2951 return 3; 2952 2953 case ARM::STRD_POST: 2954 case ARM::t2STRD_POST: 2955 return 4; 2956 2957 case ARM::LDRD_PRE: { 2958 unsigned Rt = MI.getOperand(0).getReg(); 2959 unsigned Rn = MI.getOperand(3).getReg(); 2960 unsigned Rm = MI.getOperand(4).getReg(); 2961 if (Rm) 2962 return (ARM_AM::getAM3Op(MI.getOperand(5).getImm()) == ARM_AM::sub) ? 5 2963 : 4; 2964 return (Rt == Rn) ? 4 : 3; 2965 } 2966 2967 case ARM::t2LDRD_PRE: { 2968 unsigned Rt = MI.getOperand(0).getReg(); 2969 unsigned Rn = MI.getOperand(3).getReg(); 2970 return (Rt == Rn) ? 4 : 3; 2971 } 2972 2973 case ARM::STRD_PRE: { 2974 unsigned Rm = MI.getOperand(4).getReg(); 2975 if (Rm) 2976 return (ARM_AM::getAM3Op(MI.getOperand(5).getImm()) == ARM_AM::sub) ? 5 2977 : 4; 2978 return 3; 2979 } 2980 2981 case ARM::t2STRD_PRE: 2982 return 3; 2983 2984 case ARM::t2LDR_POST: 2985 case ARM::t2LDRB_POST: 2986 case ARM::t2LDRB_PRE: 2987 case ARM::t2LDRSBi12: 2988 case ARM::t2LDRSBi8: 2989 case ARM::t2LDRSBpci: 2990 case ARM::t2LDRSBs: 2991 case ARM::t2LDRH_POST: 2992 case ARM::t2LDRH_PRE: 2993 case ARM::t2LDRSBT: 2994 case ARM::t2LDRSB_POST: 2995 case ARM::t2LDRSB_PRE: 2996 case ARM::t2LDRSH_POST: 2997 case ARM::t2LDRSH_PRE: 2998 case ARM::t2LDRSHi12: 2999 case ARM::t2LDRSHi8: 3000 case ARM::t2LDRSHpci: 3001 case ARM::t2LDRSHs: 3002 return 2; 3003 3004 case ARM::t2LDRDi8: { 3005 unsigned Rt = MI.getOperand(0).getReg(); 3006 unsigned Rn = MI.getOperand(2).getReg(); 3007 return (Rt == Rn) ? 3 : 2; 3008 } 3009 3010 case ARM::t2STRB_POST: 3011 case ARM::t2STRB_PRE: 3012 case ARM::t2STRBs: 3013 case ARM::t2STRDi8: 3014 case ARM::t2STRH_POST: 3015 case ARM::t2STRH_PRE: 3016 case ARM::t2STRHs: 3017 case ARM::t2STR_POST: 3018 case ARM::t2STR_PRE: 3019 case ARM::t2STRs: 3020 return 2; 3021 } 3022 } 3023 3024 // Return the number of 32-bit words loaded by LDM or stored by STM. If this 3025 // can't be easily determined return 0 (missing MachineMemOperand). 3026 // 3027 // FIXME: The current MachineInstr design does not support relying on machine 3028 // mem operands to determine the width of a memory access. Instead, we expect 3029 // the target to provide this information based on the instruction opcode and 3030 // operands. However, using MachineMemOperand is the best solution now for 3031 // two reasons: 3032 // 3033 // 1) getNumMicroOps tries to infer LDM memory width from the total number of MI 3034 // operands. This is much more dangerous than using the MachineMemOperand 3035 // sizes because CodeGen passes can insert/remove optional machine operands. In 3036 // fact, it's totally incorrect for preRA passes and appears to be wrong for 3037 // postRA passes as well. 3038 // 3039 // 2) getNumLDMAddresses is only used by the scheduling machine model and any 3040 // machine model that calls this should handle the unknown (zero size) case. 3041 // 3042 // Long term, we should require a target hook that verifies MachineMemOperand 3043 // sizes during MC lowering. That target hook should be local to MC lowering 3044 // because we can't ensure that it is aware of other MI forms. Doing this will 3045 // ensure that MachineMemOperands are correctly propagated through all passes. 3046 unsigned ARMBaseInstrInfo::getNumLDMAddresses(const MachineInstr &MI) const { 3047 unsigned Size = 0; 3048 for (MachineInstr::mmo_iterator I = MI.memoperands_begin(), 3049 E = MI.memoperands_end(); 3050 I != E; ++I) { 3051 Size += (*I)->getSize(); 3052 } 3053 return Size / 4; 3054 } 3055 3056 static unsigned getNumMicroOpsSingleIssuePlusExtras(unsigned Opc, 3057 unsigned NumRegs) { 3058 unsigned UOps = 1 + NumRegs; // 1 for address computation. 3059 switch (Opc) { 3060 default: 3061 break; 3062 case ARM::VLDMDIA_UPD: 3063 case ARM::VLDMDDB_UPD: 3064 case ARM::VLDMSIA_UPD: 3065 case ARM::VLDMSDB_UPD: 3066 case ARM::VSTMDIA_UPD: 3067 case ARM::VSTMDDB_UPD: 3068 case ARM::VSTMSIA_UPD: 3069 case ARM::VSTMSDB_UPD: 3070 case ARM::LDMIA_UPD: 3071 case ARM::LDMDA_UPD: 3072 case ARM::LDMDB_UPD: 3073 case ARM::LDMIB_UPD: 3074 case ARM::STMIA_UPD: 3075 case ARM::STMDA_UPD: 3076 case ARM::STMDB_UPD: 3077 case ARM::STMIB_UPD: 3078 case ARM::tLDMIA_UPD: 3079 case ARM::tSTMIA_UPD: 3080 case ARM::t2LDMIA_UPD: 3081 case ARM::t2LDMDB_UPD: 3082 case ARM::t2STMIA_UPD: 3083 case ARM::t2STMDB_UPD: 3084 ++UOps; // One for base register writeback. 3085 break; 3086 case ARM::LDMIA_RET: 3087 case ARM::tPOP_RET: 3088 case ARM::t2LDMIA_RET: 3089 UOps += 2; // One for base reg wb, one for write to pc. 3090 break; 3091 } 3092 return UOps; 3093 } 3094 3095 unsigned ARMBaseInstrInfo::getNumMicroOps(const InstrItineraryData *ItinData, 3096 const MachineInstr &MI) const { 3097 if (!ItinData || ItinData->isEmpty()) 3098 return 1; 3099 3100 const MCInstrDesc &Desc = MI.getDesc(); 3101 unsigned Class = Desc.getSchedClass(); 3102 int ItinUOps = ItinData->getNumMicroOps(Class); 3103 if (ItinUOps >= 0) { 3104 if (Subtarget.isSwift() && (Desc.mayLoad() || Desc.mayStore())) 3105 return getNumMicroOpsSwiftLdSt(ItinData, MI); 3106 3107 return ItinUOps; 3108 } 3109 3110 unsigned Opc = MI.getOpcode(); 3111 switch (Opc) { 3112 default: 3113 llvm_unreachable("Unexpected multi-uops instruction!"); 3114 case ARM::VLDMQIA: 3115 case ARM::VSTMQIA: 3116 return 2; 3117 3118 // The number of uOps for load / store multiple are determined by the number 3119 // registers. 3120 // 3121 // On Cortex-A8, each pair of register loads / stores can be scheduled on the 3122 // same cycle. The scheduling for the first load / store must be done 3123 // separately by assuming the address is not 64-bit aligned. 3124 // 3125 // On Cortex-A9, the formula is simply (#reg / 2) + (#reg % 2). If the address 3126 // is not 64-bit aligned, then AGU would take an extra cycle. For VFP / NEON 3127 // load / store multiple, the formula is (#reg / 2) + (#reg % 2) + 1. 3128 case ARM::VLDMDIA: 3129 case ARM::VLDMDIA_UPD: 3130 case ARM::VLDMDDB_UPD: 3131 case ARM::VLDMSIA: 3132 case ARM::VLDMSIA_UPD: 3133 case ARM::VLDMSDB_UPD: 3134 case ARM::VSTMDIA: 3135 case ARM::VSTMDIA_UPD: 3136 case ARM::VSTMDDB_UPD: 3137 case ARM::VSTMSIA: 3138 case ARM::VSTMSIA_UPD: 3139 case ARM::VSTMSDB_UPD: { 3140 unsigned NumRegs = MI.getNumOperands() - Desc.getNumOperands(); 3141 return (NumRegs / 2) + (NumRegs % 2) + 1; 3142 } 3143 3144 case ARM::LDMIA_RET: 3145 case ARM::LDMIA: 3146 case ARM::LDMDA: 3147 case ARM::LDMDB: 3148 case ARM::LDMIB: 3149 case ARM::LDMIA_UPD: 3150 case ARM::LDMDA_UPD: 3151 case ARM::LDMDB_UPD: 3152 case ARM::LDMIB_UPD: 3153 case ARM::STMIA: 3154 case ARM::STMDA: 3155 case ARM::STMDB: 3156 case ARM::STMIB: 3157 case ARM::STMIA_UPD: 3158 case ARM::STMDA_UPD: 3159 case ARM::STMDB_UPD: 3160 case ARM::STMIB_UPD: 3161 case ARM::tLDMIA: 3162 case ARM::tLDMIA_UPD: 3163 case ARM::tSTMIA_UPD: 3164 case ARM::tPOP_RET: 3165 case ARM::tPOP: 3166 case ARM::tPUSH: 3167 case ARM::t2LDMIA_RET: 3168 case ARM::t2LDMIA: 3169 case ARM::t2LDMDB: 3170 case ARM::t2LDMIA_UPD: 3171 case ARM::t2LDMDB_UPD: 3172 case ARM::t2STMIA: 3173 case ARM::t2STMDB: 3174 case ARM::t2STMIA_UPD: 3175 case ARM::t2STMDB_UPD: { 3176 unsigned NumRegs = MI.getNumOperands() - Desc.getNumOperands() + 1; 3177 switch (Subtarget.getLdStMultipleTiming()) { 3178 case ARMSubtarget::SingleIssuePlusExtras: 3179 return getNumMicroOpsSingleIssuePlusExtras(Opc, NumRegs); 3180 case ARMSubtarget::SingleIssue: 3181 // Assume the worst. 3182 return NumRegs; 3183 case ARMSubtarget::DoubleIssue: { 3184 if (NumRegs < 4) 3185 return 2; 3186 // 4 registers would be issued: 2, 2. 3187 // 5 registers would be issued: 2, 2, 1. 3188 unsigned UOps = (NumRegs / 2); 3189 if (NumRegs % 2) 3190 ++UOps; 3191 return UOps; 3192 } 3193 case ARMSubtarget::DoubleIssueCheckUnalignedAccess: { 3194 unsigned UOps = (NumRegs / 2); 3195 // If there are odd number of registers or if it's not 64-bit aligned, 3196 // then it takes an extra AGU (Address Generation Unit) cycle. 3197 if ((NumRegs % 2) || !MI.hasOneMemOperand() || 3198 (*MI.memoperands_begin())->getAlignment() < 8) 3199 ++UOps; 3200 return UOps; 3201 } 3202 } 3203 } 3204 } 3205 llvm_unreachable("Didn't find the number of microops"); 3206 } 3207 3208 int 3209 ARMBaseInstrInfo::getVLDMDefCycle(const InstrItineraryData *ItinData, 3210 const MCInstrDesc &DefMCID, 3211 unsigned DefClass, 3212 unsigned DefIdx, unsigned DefAlign) const { 3213 int RegNo = (int)(DefIdx+1) - DefMCID.getNumOperands() + 1; 3214 if (RegNo <= 0) 3215 // Def is the address writeback. 3216 return ItinData->getOperandCycle(DefClass, DefIdx); 3217 3218 int DefCycle; 3219 if (Subtarget.isCortexA8() || Subtarget.isCortexA7()) { 3220 // (regno / 2) + (regno % 2) + 1 3221 DefCycle = RegNo / 2 + 1; 3222 if (RegNo % 2) 3223 ++DefCycle; 3224 } else if (Subtarget.isLikeA9() || Subtarget.isSwift()) { 3225 DefCycle = RegNo; 3226 bool isSLoad = false; 3227 3228 switch (DefMCID.getOpcode()) { 3229 default: break; 3230 case ARM::VLDMSIA: 3231 case ARM::VLDMSIA_UPD: 3232 case ARM::VLDMSDB_UPD: 3233 isSLoad = true; 3234 break; 3235 } 3236 3237 // If there are odd number of 'S' registers or if it's not 64-bit aligned, 3238 // then it takes an extra cycle. 3239 if ((isSLoad && (RegNo % 2)) || DefAlign < 8) 3240 ++DefCycle; 3241 } else { 3242 // Assume the worst. 3243 DefCycle = RegNo + 2; 3244 } 3245 3246 return DefCycle; 3247 } 3248 3249 int 3250 ARMBaseInstrInfo::getLDMDefCycle(const InstrItineraryData *ItinData, 3251 const MCInstrDesc &DefMCID, 3252 unsigned DefClass, 3253 unsigned DefIdx, unsigned DefAlign) const { 3254 int RegNo = (int)(DefIdx+1) - DefMCID.getNumOperands() + 1; 3255 if (RegNo <= 0) 3256 // Def is the address writeback. 3257 return ItinData->getOperandCycle(DefClass, DefIdx); 3258 3259 int DefCycle; 3260 if (Subtarget.isCortexA8() || Subtarget.isCortexA7()) { 3261 // 4 registers would be issued: 1, 2, 1. 3262 // 5 registers would be issued: 1, 2, 2. 3263 DefCycle = RegNo / 2; 3264 if (DefCycle < 1) 3265 DefCycle = 1; 3266 // Result latency is issue cycle + 2: E2. 3267 DefCycle += 2; 3268 } else if (Subtarget.isLikeA9() || Subtarget.isSwift()) { 3269 DefCycle = (RegNo / 2); 3270 // If there are odd number of registers or if it's not 64-bit aligned, 3271 // then it takes an extra AGU (Address Generation Unit) cycle. 3272 if ((RegNo % 2) || DefAlign < 8) 3273 ++DefCycle; 3274 // Result latency is AGU cycles + 2. 3275 DefCycle += 2; 3276 } else { 3277 // Assume the worst. 3278 DefCycle = RegNo + 2; 3279 } 3280 3281 return DefCycle; 3282 } 3283 3284 int 3285 ARMBaseInstrInfo::getVSTMUseCycle(const InstrItineraryData *ItinData, 3286 const MCInstrDesc &UseMCID, 3287 unsigned UseClass, 3288 unsigned UseIdx, unsigned UseAlign) const { 3289 int RegNo = (int)(UseIdx+1) - UseMCID.getNumOperands() + 1; 3290 if (RegNo <= 0) 3291 return ItinData->getOperandCycle(UseClass, UseIdx); 3292 3293 int UseCycle; 3294 if (Subtarget.isCortexA8() || Subtarget.isCortexA7()) { 3295 // (regno / 2) + (regno % 2) + 1 3296 UseCycle = RegNo / 2 + 1; 3297 if (RegNo % 2) 3298 ++UseCycle; 3299 } else if (Subtarget.isLikeA9() || Subtarget.isSwift()) { 3300 UseCycle = RegNo; 3301 bool isSStore = false; 3302 3303 switch (UseMCID.getOpcode()) { 3304 default: break; 3305 case ARM::VSTMSIA: 3306 case ARM::VSTMSIA_UPD: 3307 case ARM::VSTMSDB_UPD: 3308 isSStore = true; 3309 break; 3310 } 3311 3312 // If there are odd number of 'S' registers or if it's not 64-bit aligned, 3313 // then it takes an extra cycle. 3314 if ((isSStore && (RegNo % 2)) || UseAlign < 8) 3315 ++UseCycle; 3316 } else { 3317 // Assume the worst. 3318 UseCycle = RegNo + 2; 3319 } 3320 3321 return UseCycle; 3322 } 3323 3324 int 3325 ARMBaseInstrInfo::getSTMUseCycle(const InstrItineraryData *ItinData, 3326 const MCInstrDesc &UseMCID, 3327 unsigned UseClass, 3328 unsigned UseIdx, unsigned UseAlign) const { 3329 int RegNo = (int)(UseIdx+1) - UseMCID.getNumOperands() + 1; 3330 if (RegNo <= 0) 3331 return ItinData->getOperandCycle(UseClass, UseIdx); 3332 3333 int UseCycle; 3334 if (Subtarget.isCortexA8() || Subtarget.isCortexA7()) { 3335 UseCycle = RegNo / 2; 3336 if (UseCycle < 2) 3337 UseCycle = 2; 3338 // Read in E3. 3339 UseCycle += 2; 3340 } else if (Subtarget.isLikeA9() || Subtarget.isSwift()) { 3341 UseCycle = (RegNo / 2); 3342 // If there are odd number of registers or if it's not 64-bit aligned, 3343 // then it takes an extra AGU (Address Generation Unit) cycle. 3344 if ((RegNo % 2) || UseAlign < 8) 3345 ++UseCycle; 3346 } else { 3347 // Assume the worst. 3348 UseCycle = 1; 3349 } 3350 return UseCycle; 3351 } 3352 3353 int 3354 ARMBaseInstrInfo::getOperandLatency(const InstrItineraryData *ItinData, 3355 const MCInstrDesc &DefMCID, 3356 unsigned DefIdx, unsigned DefAlign, 3357 const MCInstrDesc &UseMCID, 3358 unsigned UseIdx, unsigned UseAlign) const { 3359 unsigned DefClass = DefMCID.getSchedClass(); 3360 unsigned UseClass = UseMCID.getSchedClass(); 3361 3362 if (DefIdx < DefMCID.getNumDefs() && UseIdx < UseMCID.getNumOperands()) 3363 return ItinData->getOperandLatency(DefClass, DefIdx, UseClass, UseIdx); 3364 3365 // This may be a def / use of a variable_ops instruction, the operand 3366 // latency might be determinable dynamically. Let the target try to 3367 // figure it out. 3368 int DefCycle = -1; 3369 bool LdmBypass = false; 3370 switch (DefMCID.getOpcode()) { 3371 default: 3372 DefCycle = ItinData->getOperandCycle(DefClass, DefIdx); 3373 break; 3374 3375 case ARM::VLDMDIA: 3376 case ARM::VLDMDIA_UPD: 3377 case ARM::VLDMDDB_UPD: 3378 case ARM::VLDMSIA: 3379 case ARM::VLDMSIA_UPD: 3380 case ARM::VLDMSDB_UPD: 3381 DefCycle = getVLDMDefCycle(ItinData, DefMCID, DefClass, DefIdx, DefAlign); 3382 break; 3383 3384 case ARM::LDMIA_RET: 3385 case ARM::LDMIA: 3386 case ARM::LDMDA: 3387 case ARM::LDMDB: 3388 case ARM::LDMIB: 3389 case ARM::LDMIA_UPD: 3390 case ARM::LDMDA_UPD: 3391 case ARM::LDMDB_UPD: 3392 case ARM::LDMIB_UPD: 3393 case ARM::tLDMIA: 3394 case ARM::tLDMIA_UPD: 3395 case ARM::tPUSH: 3396 case ARM::t2LDMIA_RET: 3397 case ARM::t2LDMIA: 3398 case ARM::t2LDMDB: 3399 case ARM::t2LDMIA_UPD: 3400 case ARM::t2LDMDB_UPD: 3401 LdmBypass = 1; 3402 DefCycle = getLDMDefCycle(ItinData, DefMCID, DefClass, DefIdx, DefAlign); 3403 break; 3404 } 3405 3406 if (DefCycle == -1) 3407 // We can't seem to determine the result latency of the def, assume it's 2. 3408 DefCycle = 2; 3409 3410 int UseCycle = -1; 3411 switch (UseMCID.getOpcode()) { 3412 default: 3413 UseCycle = ItinData->getOperandCycle(UseClass, UseIdx); 3414 break; 3415 3416 case ARM::VSTMDIA: 3417 case ARM::VSTMDIA_UPD: 3418 case ARM::VSTMDDB_UPD: 3419 case ARM::VSTMSIA: 3420 case ARM::VSTMSIA_UPD: 3421 case ARM::VSTMSDB_UPD: 3422 UseCycle = getVSTMUseCycle(ItinData, UseMCID, UseClass, UseIdx, UseAlign); 3423 break; 3424 3425 case ARM::STMIA: 3426 case ARM::STMDA: 3427 case ARM::STMDB: 3428 case ARM::STMIB: 3429 case ARM::STMIA_UPD: 3430 case ARM::STMDA_UPD: 3431 case ARM::STMDB_UPD: 3432 case ARM::STMIB_UPD: 3433 case ARM::tSTMIA_UPD: 3434 case ARM::tPOP_RET: 3435 case ARM::tPOP: 3436 case ARM::t2STMIA: 3437 case ARM::t2STMDB: 3438 case ARM::t2STMIA_UPD: 3439 case ARM::t2STMDB_UPD: 3440 UseCycle = getSTMUseCycle(ItinData, UseMCID, UseClass, UseIdx, UseAlign); 3441 break; 3442 } 3443 3444 if (UseCycle == -1) 3445 // Assume it's read in the first stage. 3446 UseCycle = 1; 3447 3448 UseCycle = DefCycle - UseCycle + 1; 3449 if (UseCycle > 0) { 3450 if (LdmBypass) { 3451 // It's a variable_ops instruction so we can't use DefIdx here. Just use 3452 // first def operand. 3453 if (ItinData->hasPipelineForwarding(DefClass, DefMCID.getNumOperands()-1, 3454 UseClass, UseIdx)) 3455 --UseCycle; 3456 } else if (ItinData->hasPipelineForwarding(DefClass, DefIdx, 3457 UseClass, UseIdx)) { 3458 --UseCycle; 3459 } 3460 } 3461 3462 return UseCycle; 3463 } 3464 3465 static const MachineInstr *getBundledDefMI(const TargetRegisterInfo *TRI, 3466 const MachineInstr *MI, unsigned Reg, 3467 unsigned &DefIdx, unsigned &Dist) { 3468 Dist = 0; 3469 3470 MachineBasicBlock::const_iterator I = MI; ++I; 3471 MachineBasicBlock::const_instr_iterator II = std::prev(I.getInstrIterator()); 3472 assert(II->isInsideBundle() && "Empty bundle?"); 3473 3474 int Idx = -1; 3475 while (II->isInsideBundle()) { 3476 Idx = II->findRegisterDefOperandIdx(Reg, false, true, TRI); 3477 if (Idx != -1) 3478 break; 3479 --II; 3480 ++Dist; 3481 } 3482 3483 assert(Idx != -1 && "Cannot find bundled definition!"); 3484 DefIdx = Idx; 3485 return &*II; 3486 } 3487 3488 static const MachineInstr *getBundledUseMI(const TargetRegisterInfo *TRI, 3489 const MachineInstr &MI, unsigned Reg, 3490 unsigned &UseIdx, unsigned &Dist) { 3491 Dist = 0; 3492 3493 MachineBasicBlock::const_instr_iterator II = ++MI.getIterator(); 3494 assert(II->isInsideBundle() && "Empty bundle?"); 3495 MachineBasicBlock::const_instr_iterator E = MI.getParent()->instr_end(); 3496 3497 // FIXME: This doesn't properly handle multiple uses. 3498 int Idx = -1; 3499 while (II != E && II->isInsideBundle()) { 3500 Idx = II->findRegisterUseOperandIdx(Reg, false, TRI); 3501 if (Idx != -1) 3502 break; 3503 if (II->getOpcode() != ARM::t2IT) 3504 ++Dist; 3505 ++II; 3506 } 3507 3508 if (Idx == -1) { 3509 Dist = 0; 3510 return nullptr; 3511 } 3512 3513 UseIdx = Idx; 3514 return &*II; 3515 } 3516 3517 /// Return the number of cycles to add to (or subtract from) the static 3518 /// itinerary based on the def opcode and alignment. The caller will ensure that 3519 /// adjusted latency is at least one cycle. 3520 static int adjustDefLatency(const ARMSubtarget &Subtarget, 3521 const MachineInstr &DefMI, 3522 const MCInstrDesc &DefMCID, unsigned DefAlign) { 3523 int Adjust = 0; 3524 if (Subtarget.isCortexA8() || Subtarget.isLikeA9() || Subtarget.isCortexA7()) { 3525 // FIXME: Shifter op hack: no shift (i.e. [r +/- r]) or [r + r << 2] 3526 // variants are one cycle cheaper. 3527 switch (DefMCID.getOpcode()) { 3528 default: break; 3529 case ARM::LDRrs: 3530 case ARM::LDRBrs: { 3531 unsigned ShOpVal = DefMI.getOperand(3).getImm(); 3532 unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); 3533 if (ShImm == 0 || 3534 (ShImm == 2 && ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl)) 3535 --Adjust; 3536 break; 3537 } 3538 case ARM::t2LDRs: 3539 case ARM::t2LDRBs: 3540 case ARM::t2LDRHs: 3541 case ARM::t2LDRSHs: { 3542 // Thumb2 mode: lsl only. 3543 unsigned ShAmt = DefMI.getOperand(3).getImm(); 3544 if (ShAmt == 0 || ShAmt == 2) 3545 --Adjust; 3546 break; 3547 } 3548 } 3549 } else if (Subtarget.isSwift()) { 3550 // FIXME: Properly handle all of the latency adjustments for address 3551 // writeback. 3552 switch (DefMCID.getOpcode()) { 3553 default: break; 3554 case ARM::LDRrs: 3555 case ARM::LDRBrs: { 3556 unsigned ShOpVal = DefMI.getOperand(3).getImm(); 3557 bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub; 3558 unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); 3559 if (!isSub && 3560 (ShImm == 0 || 3561 ((ShImm == 1 || ShImm == 2 || ShImm == 3) && 3562 ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl))) 3563 Adjust -= 2; 3564 else if (!isSub && 3565 ShImm == 1 && ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsr) 3566 --Adjust; 3567 break; 3568 } 3569 case ARM::t2LDRs: 3570 case ARM::t2LDRBs: 3571 case ARM::t2LDRHs: 3572 case ARM::t2LDRSHs: { 3573 // Thumb2 mode: lsl only. 3574 unsigned ShAmt = DefMI.getOperand(3).getImm(); 3575 if (ShAmt == 0 || ShAmt == 1 || ShAmt == 2 || ShAmt == 3) 3576 Adjust -= 2; 3577 break; 3578 } 3579 } 3580 } 3581 3582 if (DefAlign < 8 && Subtarget.checkVLDnAccessAlignment()) { 3583 switch (DefMCID.getOpcode()) { 3584 default: break; 3585 case ARM::VLD1q8: 3586 case ARM::VLD1q16: 3587 case ARM::VLD1q32: 3588 case ARM::VLD1q64: 3589 case ARM::VLD1q8wb_fixed: 3590 case ARM::VLD1q16wb_fixed: 3591 case ARM::VLD1q32wb_fixed: 3592 case ARM::VLD1q64wb_fixed: 3593 case ARM::VLD1q8wb_register: 3594 case ARM::VLD1q16wb_register: 3595 case ARM::VLD1q32wb_register: 3596 case ARM::VLD1q64wb_register: 3597 case ARM::VLD2d8: 3598 case ARM::VLD2d16: 3599 case ARM::VLD2d32: 3600 case ARM::VLD2q8: 3601 case ARM::VLD2q16: 3602 case ARM::VLD2q32: 3603 case ARM::VLD2d8wb_fixed: 3604 case ARM::VLD2d16wb_fixed: 3605 case ARM::VLD2d32wb_fixed: 3606 case ARM::VLD2q8wb_fixed: 3607 case ARM::VLD2q16wb_fixed: 3608 case ARM::VLD2q32wb_fixed: 3609 case ARM::VLD2d8wb_register: 3610 case ARM::VLD2d16wb_register: 3611 case ARM::VLD2d32wb_register: 3612 case ARM::VLD2q8wb_register: 3613 case ARM::VLD2q16wb_register: 3614 case ARM::VLD2q32wb_register: 3615 case ARM::VLD3d8: 3616 case ARM::VLD3d16: 3617 case ARM::VLD3d32: 3618 case ARM::VLD1d64T: 3619 case ARM::VLD3d8_UPD: 3620 case ARM::VLD3d16_UPD: 3621 case ARM::VLD3d32_UPD: 3622 case ARM::VLD1d64Twb_fixed: 3623 case ARM::VLD1d64Twb_register: 3624 case ARM::VLD3q8_UPD: 3625 case ARM::VLD3q16_UPD: 3626 case ARM::VLD3q32_UPD: 3627 case ARM::VLD4d8: 3628 case ARM::VLD4d16: 3629 case ARM::VLD4d32: 3630 case ARM::VLD1d64Q: 3631 case ARM::VLD4d8_UPD: 3632 case ARM::VLD4d16_UPD: 3633 case ARM::VLD4d32_UPD: 3634 case ARM::VLD1d64Qwb_fixed: 3635 case ARM::VLD1d64Qwb_register: 3636 case ARM::VLD4q8_UPD: 3637 case ARM::VLD4q16_UPD: 3638 case ARM::VLD4q32_UPD: 3639 case ARM::VLD1DUPq8: 3640 case ARM::VLD1DUPq16: 3641 case ARM::VLD1DUPq32: 3642 case ARM::VLD1DUPq8wb_fixed: 3643 case ARM::VLD1DUPq16wb_fixed: 3644 case ARM::VLD1DUPq32wb_fixed: 3645 case ARM::VLD1DUPq8wb_register: 3646 case ARM::VLD1DUPq16wb_register: 3647 case ARM::VLD1DUPq32wb_register: 3648 case ARM::VLD2DUPd8: 3649 case ARM::VLD2DUPd16: 3650 case ARM::VLD2DUPd32: 3651 case ARM::VLD2DUPd8wb_fixed: 3652 case ARM::VLD2DUPd16wb_fixed: 3653 case ARM::VLD2DUPd32wb_fixed: 3654 case ARM::VLD2DUPd8wb_register: 3655 case ARM::VLD2DUPd16wb_register: 3656 case ARM::VLD2DUPd32wb_register: 3657 case ARM::VLD4DUPd8: 3658 case ARM::VLD4DUPd16: 3659 case ARM::VLD4DUPd32: 3660 case ARM::VLD4DUPd8_UPD: 3661 case ARM::VLD4DUPd16_UPD: 3662 case ARM::VLD4DUPd32_UPD: 3663 case ARM::VLD1LNd8: 3664 case ARM::VLD1LNd16: 3665 case ARM::VLD1LNd32: 3666 case ARM::VLD1LNd8_UPD: 3667 case ARM::VLD1LNd16_UPD: 3668 case ARM::VLD1LNd32_UPD: 3669 case ARM::VLD2LNd8: 3670 case ARM::VLD2LNd16: 3671 case ARM::VLD2LNd32: 3672 case ARM::VLD2LNq16: 3673 case ARM::VLD2LNq32: 3674 case ARM::VLD2LNd8_UPD: 3675 case ARM::VLD2LNd16_UPD: 3676 case ARM::VLD2LNd32_UPD: 3677 case ARM::VLD2LNq16_UPD: 3678 case ARM::VLD2LNq32_UPD: 3679 case ARM::VLD4LNd8: 3680 case ARM::VLD4LNd16: 3681 case ARM::VLD4LNd32: 3682 case ARM::VLD4LNq16: 3683 case ARM::VLD4LNq32: 3684 case ARM::VLD4LNd8_UPD: 3685 case ARM::VLD4LNd16_UPD: 3686 case ARM::VLD4LNd32_UPD: 3687 case ARM::VLD4LNq16_UPD: 3688 case ARM::VLD4LNq32_UPD: 3689 // If the address is not 64-bit aligned, the latencies of these 3690 // instructions increases by one. 3691 ++Adjust; 3692 break; 3693 } 3694 } 3695 return Adjust; 3696 } 3697 3698 int ARMBaseInstrInfo::getOperandLatency(const InstrItineraryData *ItinData, 3699 const MachineInstr &DefMI, 3700 unsigned DefIdx, 3701 const MachineInstr &UseMI, 3702 unsigned UseIdx) const { 3703 // No operand latency. The caller may fall back to getInstrLatency. 3704 if (!ItinData || ItinData->isEmpty()) 3705 return -1; 3706 3707 const MachineOperand &DefMO = DefMI.getOperand(DefIdx); 3708 unsigned Reg = DefMO.getReg(); 3709 3710 const MachineInstr *ResolvedDefMI = &DefMI; 3711 unsigned DefAdj = 0; 3712 if (DefMI.isBundle()) 3713 ResolvedDefMI = 3714 getBundledDefMI(&getRegisterInfo(), &DefMI, Reg, DefIdx, DefAdj); 3715 if (ResolvedDefMI->isCopyLike() || ResolvedDefMI->isInsertSubreg() || 3716 ResolvedDefMI->isRegSequence() || ResolvedDefMI->isImplicitDef()) { 3717 return 1; 3718 } 3719 3720 const MachineInstr *ResolvedUseMI = &UseMI; 3721 unsigned UseAdj = 0; 3722 if (UseMI.isBundle()) { 3723 ResolvedUseMI = 3724 getBundledUseMI(&getRegisterInfo(), UseMI, Reg, UseIdx, UseAdj); 3725 if (!ResolvedUseMI) 3726 return -1; 3727 } 3728 3729 return getOperandLatencyImpl( 3730 ItinData, *ResolvedDefMI, DefIdx, ResolvedDefMI->getDesc(), DefAdj, DefMO, 3731 Reg, *ResolvedUseMI, UseIdx, ResolvedUseMI->getDesc(), UseAdj); 3732 } 3733 3734 int ARMBaseInstrInfo::getOperandLatencyImpl( 3735 const InstrItineraryData *ItinData, const MachineInstr &DefMI, 3736 unsigned DefIdx, const MCInstrDesc &DefMCID, unsigned DefAdj, 3737 const MachineOperand &DefMO, unsigned Reg, const MachineInstr &UseMI, 3738 unsigned UseIdx, const MCInstrDesc &UseMCID, unsigned UseAdj) const { 3739 if (Reg == ARM::CPSR) { 3740 if (DefMI.getOpcode() == ARM::FMSTAT) { 3741 // fpscr -> cpsr stalls over 20 cycles on A8 (and earlier?) 3742 return Subtarget.isLikeA9() ? 1 : 20; 3743 } 3744 3745 // CPSR set and branch can be paired in the same cycle. 3746 if (UseMI.isBranch()) 3747 return 0; 3748 3749 // Otherwise it takes the instruction latency (generally one). 3750 unsigned Latency = getInstrLatency(ItinData, DefMI); 3751 3752 // For Thumb2 and -Os, prefer scheduling CPSR setting instruction close to 3753 // its uses. Instructions which are otherwise scheduled between them may 3754 // incur a code size penalty (not able to use the CPSR setting 16-bit 3755 // instructions). 3756 if (Latency > 0 && Subtarget.isThumb2()) { 3757 const MachineFunction *MF = DefMI.getParent()->getParent(); 3758 // FIXME: Use Function::optForSize(). 3759 if (MF->getFunction()->hasFnAttribute(Attribute::OptimizeForSize)) 3760 --Latency; 3761 } 3762 return Latency; 3763 } 3764 3765 if (DefMO.isImplicit() || UseMI.getOperand(UseIdx).isImplicit()) 3766 return -1; 3767 3768 unsigned DefAlign = DefMI.hasOneMemOperand() 3769 ? (*DefMI.memoperands_begin())->getAlignment() 3770 : 0; 3771 unsigned UseAlign = UseMI.hasOneMemOperand() 3772 ? (*UseMI.memoperands_begin())->getAlignment() 3773 : 0; 3774 3775 // Get the itinerary's latency if possible, and handle variable_ops. 3776 int Latency = getOperandLatency(ItinData, DefMCID, DefIdx, DefAlign, UseMCID, 3777 UseIdx, UseAlign); 3778 // Unable to find operand latency. The caller may resort to getInstrLatency. 3779 if (Latency < 0) 3780 return Latency; 3781 3782 // Adjust for IT block position. 3783 int Adj = DefAdj + UseAdj; 3784 3785 // Adjust for dynamic def-side opcode variants not captured by the itinerary. 3786 Adj += adjustDefLatency(Subtarget, DefMI, DefMCID, DefAlign); 3787 if (Adj >= 0 || (int)Latency > -Adj) { 3788 return Latency + Adj; 3789 } 3790 // Return the itinerary latency, which may be zero but not less than zero. 3791 return Latency; 3792 } 3793 3794 int 3795 ARMBaseInstrInfo::getOperandLatency(const InstrItineraryData *ItinData, 3796 SDNode *DefNode, unsigned DefIdx, 3797 SDNode *UseNode, unsigned UseIdx) const { 3798 if (!DefNode->isMachineOpcode()) 3799 return 1; 3800 3801 const MCInstrDesc &DefMCID = get(DefNode->getMachineOpcode()); 3802 3803 if (isZeroCost(DefMCID.Opcode)) 3804 return 0; 3805 3806 if (!ItinData || ItinData->isEmpty()) 3807 return DefMCID.mayLoad() ? 3 : 1; 3808 3809 if (!UseNode->isMachineOpcode()) { 3810 int Latency = ItinData->getOperandCycle(DefMCID.getSchedClass(), DefIdx); 3811 int Adj = Subtarget.getPreISelOperandLatencyAdjustment(); 3812 int Threshold = 1 + Adj; 3813 return Latency <= Threshold ? 1 : Latency - Adj; 3814 } 3815 3816 const MCInstrDesc &UseMCID = get(UseNode->getMachineOpcode()); 3817 const MachineSDNode *DefMN = dyn_cast<MachineSDNode>(DefNode); 3818 unsigned DefAlign = !DefMN->memoperands_empty() 3819 ? (*DefMN->memoperands_begin())->getAlignment() : 0; 3820 const MachineSDNode *UseMN = dyn_cast<MachineSDNode>(UseNode); 3821 unsigned UseAlign = !UseMN->memoperands_empty() 3822 ? (*UseMN->memoperands_begin())->getAlignment() : 0; 3823 int Latency = getOperandLatency(ItinData, DefMCID, DefIdx, DefAlign, 3824 UseMCID, UseIdx, UseAlign); 3825 3826 if (Latency > 1 && 3827 (Subtarget.isCortexA8() || Subtarget.isLikeA9() || 3828 Subtarget.isCortexA7())) { 3829 // FIXME: Shifter op hack: no shift (i.e. [r +/- r]) or [r + r << 2] 3830 // variants are one cycle cheaper. 3831 switch (DefMCID.getOpcode()) { 3832 default: break; 3833 case ARM::LDRrs: 3834 case ARM::LDRBrs: { 3835 unsigned ShOpVal = 3836 cast<ConstantSDNode>(DefNode->getOperand(2))->getZExtValue(); 3837 unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); 3838 if (ShImm == 0 || 3839 (ShImm == 2 && ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl)) 3840 --Latency; 3841 break; 3842 } 3843 case ARM::t2LDRs: 3844 case ARM::t2LDRBs: 3845 case ARM::t2LDRHs: 3846 case ARM::t2LDRSHs: { 3847 // Thumb2 mode: lsl only. 3848 unsigned ShAmt = 3849 cast<ConstantSDNode>(DefNode->getOperand(2))->getZExtValue(); 3850 if (ShAmt == 0 || ShAmt == 2) 3851 --Latency; 3852 break; 3853 } 3854 } 3855 } else if (DefIdx == 0 && Latency > 2 && Subtarget.isSwift()) { 3856 // FIXME: Properly handle all of the latency adjustments for address 3857 // writeback. 3858 switch (DefMCID.getOpcode()) { 3859 default: break; 3860 case ARM::LDRrs: 3861 case ARM::LDRBrs: { 3862 unsigned ShOpVal = 3863 cast<ConstantSDNode>(DefNode->getOperand(2))->getZExtValue(); 3864 unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); 3865 if (ShImm == 0 || 3866 ((ShImm == 1 || ShImm == 2 || ShImm == 3) && 3867 ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl)) 3868 Latency -= 2; 3869 else if (ShImm == 1 && ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsr) 3870 --Latency; 3871 break; 3872 } 3873 case ARM::t2LDRs: 3874 case ARM::t2LDRBs: 3875 case ARM::t2LDRHs: 3876 case ARM::t2LDRSHs: { 3877 // Thumb2 mode: lsl 0-3 only. 3878 Latency -= 2; 3879 break; 3880 } 3881 } 3882 } 3883 3884 if (DefAlign < 8 && Subtarget.checkVLDnAccessAlignment()) 3885 switch (DefMCID.getOpcode()) { 3886 default: break; 3887 case ARM::VLD1q8: 3888 case ARM::VLD1q16: 3889 case ARM::VLD1q32: 3890 case ARM::VLD1q64: 3891 case ARM::VLD1q8wb_register: 3892 case ARM::VLD1q16wb_register: 3893 case ARM::VLD1q32wb_register: 3894 case ARM::VLD1q64wb_register: 3895 case ARM::VLD1q8wb_fixed: 3896 case ARM::VLD1q16wb_fixed: 3897 case ARM::VLD1q32wb_fixed: 3898 case ARM::VLD1q64wb_fixed: 3899 case ARM::VLD2d8: 3900 case ARM::VLD2d16: 3901 case ARM::VLD2d32: 3902 case ARM::VLD2q8Pseudo: 3903 case ARM::VLD2q16Pseudo: 3904 case ARM::VLD2q32Pseudo: 3905 case ARM::VLD2d8wb_fixed: 3906 case ARM::VLD2d16wb_fixed: 3907 case ARM::VLD2d32wb_fixed: 3908 case ARM::VLD2q8PseudoWB_fixed: 3909 case ARM::VLD2q16PseudoWB_fixed: 3910 case ARM::VLD2q32PseudoWB_fixed: 3911 case ARM::VLD2d8wb_register: 3912 case ARM::VLD2d16wb_register: 3913 case ARM::VLD2d32wb_register: 3914 case ARM::VLD2q8PseudoWB_register: 3915 case ARM::VLD2q16PseudoWB_register: 3916 case ARM::VLD2q32PseudoWB_register: 3917 case ARM::VLD3d8Pseudo: 3918 case ARM::VLD3d16Pseudo: 3919 case ARM::VLD3d32Pseudo: 3920 case ARM::VLD1d64TPseudo: 3921 case ARM::VLD1d64TPseudoWB_fixed: 3922 case ARM::VLD3d8Pseudo_UPD: 3923 case ARM::VLD3d16Pseudo_UPD: 3924 case ARM::VLD3d32Pseudo_UPD: 3925 case ARM::VLD3q8Pseudo_UPD: 3926 case ARM::VLD3q16Pseudo_UPD: 3927 case ARM::VLD3q32Pseudo_UPD: 3928 case ARM::VLD3q8oddPseudo: 3929 case ARM::VLD3q16oddPseudo: 3930 case ARM::VLD3q32oddPseudo: 3931 case ARM::VLD3q8oddPseudo_UPD: 3932 case ARM::VLD3q16oddPseudo_UPD: 3933 case ARM::VLD3q32oddPseudo_UPD: 3934 case ARM::VLD4d8Pseudo: 3935 case ARM::VLD4d16Pseudo: 3936 case ARM::VLD4d32Pseudo: 3937 case ARM::VLD1d64QPseudo: 3938 case ARM::VLD1d64QPseudoWB_fixed: 3939 case ARM::VLD4d8Pseudo_UPD: 3940 case ARM::VLD4d16Pseudo_UPD: 3941 case ARM::VLD4d32Pseudo_UPD: 3942 case ARM::VLD4q8Pseudo_UPD: 3943 case ARM::VLD4q16Pseudo_UPD: 3944 case ARM::VLD4q32Pseudo_UPD: 3945 case ARM::VLD4q8oddPseudo: 3946 case ARM::VLD4q16oddPseudo: 3947 case ARM::VLD4q32oddPseudo: 3948 case ARM::VLD4q8oddPseudo_UPD: 3949 case ARM::VLD4q16oddPseudo_UPD: 3950 case ARM::VLD4q32oddPseudo_UPD: 3951 case ARM::VLD1DUPq8: 3952 case ARM::VLD1DUPq16: 3953 case ARM::VLD1DUPq32: 3954 case ARM::VLD1DUPq8wb_fixed: 3955 case ARM::VLD1DUPq16wb_fixed: 3956 case ARM::VLD1DUPq32wb_fixed: 3957 case ARM::VLD1DUPq8wb_register: 3958 case ARM::VLD1DUPq16wb_register: 3959 case ARM::VLD1DUPq32wb_register: 3960 case ARM::VLD2DUPd8: 3961 case ARM::VLD2DUPd16: 3962 case ARM::VLD2DUPd32: 3963 case ARM::VLD2DUPd8wb_fixed: 3964 case ARM::VLD2DUPd16wb_fixed: 3965 case ARM::VLD2DUPd32wb_fixed: 3966 case ARM::VLD2DUPd8wb_register: 3967 case ARM::VLD2DUPd16wb_register: 3968 case ARM::VLD2DUPd32wb_register: 3969 case ARM::VLD4DUPd8Pseudo: 3970 case ARM::VLD4DUPd16Pseudo: 3971 case ARM::VLD4DUPd32Pseudo: 3972 case ARM::VLD4DUPd8Pseudo_UPD: 3973 case ARM::VLD4DUPd16Pseudo_UPD: 3974 case ARM::VLD4DUPd32Pseudo_UPD: 3975 case ARM::VLD1LNq8Pseudo: 3976 case ARM::VLD1LNq16Pseudo: 3977 case ARM::VLD1LNq32Pseudo: 3978 case ARM::VLD1LNq8Pseudo_UPD: 3979 case ARM::VLD1LNq16Pseudo_UPD: 3980 case ARM::VLD1LNq32Pseudo_UPD: 3981 case ARM::VLD2LNd8Pseudo: 3982 case ARM::VLD2LNd16Pseudo: 3983 case ARM::VLD2LNd32Pseudo: 3984 case ARM::VLD2LNq16Pseudo: 3985 case ARM::VLD2LNq32Pseudo: 3986 case ARM::VLD2LNd8Pseudo_UPD: 3987 case ARM::VLD2LNd16Pseudo_UPD: 3988 case ARM::VLD2LNd32Pseudo_UPD: 3989 case ARM::VLD2LNq16Pseudo_UPD: 3990 case ARM::VLD2LNq32Pseudo_UPD: 3991 case ARM::VLD4LNd8Pseudo: 3992 case ARM::VLD4LNd16Pseudo: 3993 case ARM::VLD4LNd32Pseudo: 3994 case ARM::VLD4LNq16Pseudo: 3995 case ARM::VLD4LNq32Pseudo: 3996 case ARM::VLD4LNd8Pseudo_UPD: 3997 case ARM::VLD4LNd16Pseudo_UPD: 3998 case ARM::VLD4LNd32Pseudo_UPD: 3999 case ARM::VLD4LNq16Pseudo_UPD: 4000 case ARM::VLD4LNq32Pseudo_UPD: 4001 // If the address is not 64-bit aligned, the latencies of these 4002 // instructions increases by one. 4003 ++Latency; 4004 break; 4005 } 4006 4007 return Latency; 4008 } 4009 4010 unsigned ARMBaseInstrInfo::getPredicationCost(const MachineInstr &MI) const { 4011 if (MI.isCopyLike() || MI.isInsertSubreg() || MI.isRegSequence() || 4012 MI.isImplicitDef()) 4013 return 0; 4014 4015 if (MI.isBundle()) 4016 return 0; 4017 4018 const MCInstrDesc &MCID = MI.getDesc(); 4019 4020 if (MCID.isCall() || MCID.hasImplicitDefOfPhysReg(ARM::CPSR)) { 4021 // When predicated, CPSR is an additional source operand for CPSR updating 4022 // instructions, this apparently increases their latencies. 4023 return 1; 4024 } 4025 return 0; 4026 } 4027 4028 unsigned ARMBaseInstrInfo::getInstrLatency(const InstrItineraryData *ItinData, 4029 const MachineInstr &MI, 4030 unsigned *PredCost) const { 4031 if (MI.isCopyLike() || MI.isInsertSubreg() || MI.isRegSequence() || 4032 MI.isImplicitDef()) 4033 return 1; 4034 4035 // An instruction scheduler typically runs on unbundled instructions, however 4036 // other passes may query the latency of a bundled instruction. 4037 if (MI.isBundle()) { 4038 unsigned Latency = 0; 4039 MachineBasicBlock::const_instr_iterator I = MI.getIterator(); 4040 MachineBasicBlock::const_instr_iterator E = MI.getParent()->instr_end(); 4041 while (++I != E && I->isInsideBundle()) { 4042 if (I->getOpcode() != ARM::t2IT) 4043 Latency += getInstrLatency(ItinData, *I, PredCost); 4044 } 4045 return Latency; 4046 } 4047 4048 const MCInstrDesc &MCID = MI.getDesc(); 4049 if (PredCost && (MCID.isCall() || MCID.hasImplicitDefOfPhysReg(ARM::CPSR))) { 4050 // When predicated, CPSR is an additional source operand for CPSR updating 4051 // instructions, this apparently increases their latencies. 4052 *PredCost = 1; 4053 } 4054 // Be sure to call getStageLatency for an empty itinerary in case it has a 4055 // valid MinLatency property. 4056 if (!ItinData) 4057 return MI.mayLoad() ? 3 : 1; 4058 4059 unsigned Class = MCID.getSchedClass(); 4060 4061 // For instructions with variable uops, use uops as latency. 4062 if (!ItinData->isEmpty() && ItinData->getNumMicroOps(Class) < 0) 4063 return getNumMicroOps(ItinData, MI); 4064 4065 // For the common case, fall back on the itinerary's latency. 4066 unsigned Latency = ItinData->getStageLatency(Class); 4067 4068 // Adjust for dynamic def-side opcode variants not captured by the itinerary. 4069 unsigned DefAlign = 4070 MI.hasOneMemOperand() ? (*MI.memoperands_begin())->getAlignment() : 0; 4071 int Adj = adjustDefLatency(Subtarget, MI, MCID, DefAlign); 4072 if (Adj >= 0 || (int)Latency > -Adj) { 4073 return Latency + Adj; 4074 } 4075 return Latency; 4076 } 4077 4078 int ARMBaseInstrInfo::getInstrLatency(const InstrItineraryData *ItinData, 4079 SDNode *Node) const { 4080 if (!Node->isMachineOpcode()) 4081 return 1; 4082 4083 if (!ItinData || ItinData->isEmpty()) 4084 return 1; 4085 4086 unsigned Opcode = Node->getMachineOpcode(); 4087 switch (Opcode) { 4088 default: 4089 return ItinData->getStageLatency(get(Opcode).getSchedClass()); 4090 case ARM::VLDMQIA: 4091 case ARM::VSTMQIA: 4092 return 2; 4093 } 4094 } 4095 4096 bool ARMBaseInstrInfo::hasHighOperandLatency(const TargetSchedModel &SchedModel, 4097 const MachineRegisterInfo *MRI, 4098 const MachineInstr &DefMI, 4099 unsigned DefIdx, 4100 const MachineInstr &UseMI, 4101 unsigned UseIdx) const { 4102 unsigned DDomain = DefMI.getDesc().TSFlags & ARMII::DomainMask; 4103 unsigned UDomain = UseMI.getDesc().TSFlags & ARMII::DomainMask; 4104 if (Subtarget.nonpipelinedVFP() && 4105 (DDomain == ARMII::DomainVFP || UDomain == ARMII::DomainVFP)) 4106 return true; 4107 4108 // Hoist VFP / NEON instructions with 4 or higher latency. 4109 unsigned Latency = 4110 SchedModel.computeOperandLatency(&DefMI, DefIdx, &UseMI, UseIdx); 4111 if (Latency <= 3) 4112 return false; 4113 return DDomain == ARMII::DomainVFP || DDomain == ARMII::DomainNEON || 4114 UDomain == ARMII::DomainVFP || UDomain == ARMII::DomainNEON; 4115 } 4116 4117 bool ARMBaseInstrInfo::hasLowDefLatency(const TargetSchedModel &SchedModel, 4118 const MachineInstr &DefMI, 4119 unsigned DefIdx) const { 4120 const InstrItineraryData *ItinData = SchedModel.getInstrItineraries(); 4121 if (!ItinData || ItinData->isEmpty()) 4122 return false; 4123 4124 unsigned DDomain = DefMI.getDesc().TSFlags & ARMII::DomainMask; 4125 if (DDomain == ARMII::DomainGeneral) { 4126 unsigned DefClass = DefMI.getDesc().getSchedClass(); 4127 int DefCycle = ItinData->getOperandCycle(DefClass, DefIdx); 4128 return (DefCycle != -1 && DefCycle <= 2); 4129 } 4130 return false; 4131 } 4132 4133 bool ARMBaseInstrInfo::verifyInstruction(const MachineInstr &MI, 4134 StringRef &ErrInfo) const { 4135 if (convertAddSubFlagsOpcode(MI.getOpcode())) { 4136 ErrInfo = "Pseudo flag setting opcodes only exist in Selection DAG"; 4137 return false; 4138 } 4139 return true; 4140 } 4141 4142 // LoadStackGuard has so far only been implemented for MachO. Different code 4143 // sequence is needed for other targets. 4144 void ARMBaseInstrInfo::expandLoadStackGuardBase(MachineBasicBlock::iterator MI, 4145 unsigned LoadImmOpc, 4146 unsigned LoadOpc) const { 4147 assert(!Subtarget.isROPI() && !Subtarget.isRWPI() && 4148 "ROPI/RWPI not currently supported with stack guard"); 4149 4150 MachineBasicBlock &MBB = *MI->getParent(); 4151 DebugLoc DL = MI->getDebugLoc(); 4152 unsigned Reg = MI->getOperand(0).getReg(); 4153 const GlobalValue *GV = 4154 cast<GlobalValue>((*MI->memoperands_begin())->getValue()); 4155 MachineInstrBuilder MIB; 4156 4157 BuildMI(MBB, MI, DL, get(LoadImmOpc), Reg) 4158 .addGlobalAddress(GV, 0, ARMII::MO_NONLAZY); 4159 4160 if (Subtarget.isGVIndirectSymbol(GV)) { 4161 MIB = BuildMI(MBB, MI, DL, get(LoadOpc), Reg); 4162 MIB.addReg(Reg, RegState::Kill).addImm(0); 4163 auto Flags = MachineMemOperand::MOLoad | 4164 MachineMemOperand::MODereferenceable | 4165 MachineMemOperand::MOInvariant; 4166 MachineMemOperand *MMO = MBB.getParent()->getMachineMemOperand( 4167 MachinePointerInfo::getGOT(*MBB.getParent()), Flags, 4, 4); 4168 MIB.addMemOperand(MMO); 4169 AddDefaultPred(MIB); 4170 } 4171 4172 MIB = BuildMI(MBB, MI, DL, get(LoadOpc), Reg); 4173 MIB.addReg(Reg, RegState::Kill).addImm(0); 4174 MIB.setMemRefs(MI->memoperands_begin(), MI->memoperands_end()); 4175 AddDefaultPred(MIB); 4176 } 4177 4178 bool 4179 ARMBaseInstrInfo::isFpMLxInstruction(unsigned Opcode, unsigned &MulOpc, 4180 unsigned &AddSubOpc, 4181 bool &NegAcc, bool &HasLane) const { 4182 DenseMap<unsigned, unsigned>::const_iterator I = MLxEntryMap.find(Opcode); 4183 if (I == MLxEntryMap.end()) 4184 return false; 4185 4186 const ARM_MLxEntry &Entry = ARM_MLxTable[I->second]; 4187 MulOpc = Entry.MulOpc; 4188 AddSubOpc = Entry.AddSubOpc; 4189 NegAcc = Entry.NegAcc; 4190 HasLane = Entry.HasLane; 4191 return true; 4192 } 4193 4194 //===----------------------------------------------------------------------===// 4195 // Execution domains. 4196 //===----------------------------------------------------------------------===// 4197 // 4198 // Some instructions go down the NEON pipeline, some go down the VFP pipeline, 4199 // and some can go down both. The vmov instructions go down the VFP pipeline, 4200 // but they can be changed to vorr equivalents that are executed by the NEON 4201 // pipeline. 4202 // 4203 // We use the following execution domain numbering: 4204 // 4205 enum ARMExeDomain { 4206 ExeGeneric = 0, 4207 ExeVFP = 1, 4208 ExeNEON = 2 4209 }; 4210 // 4211 // Also see ARMInstrFormats.td and Domain* enums in ARMBaseInfo.h 4212 // 4213 std::pair<uint16_t, uint16_t> 4214 ARMBaseInstrInfo::getExecutionDomain(const MachineInstr &MI) const { 4215 // If we don't have access to NEON instructions then we won't be able 4216 // to swizzle anything to the NEON domain. Check to make sure. 4217 if (Subtarget.hasNEON()) { 4218 // VMOVD, VMOVRS and VMOVSR are VFP instructions, but can be changed to NEON 4219 // if they are not predicated. 4220 if (MI.getOpcode() == ARM::VMOVD && !isPredicated(MI)) 4221 return std::make_pair(ExeVFP, (1 << ExeVFP) | (1 << ExeNEON)); 4222 4223 // CortexA9 is particularly picky about mixing the two and wants these 4224 // converted. 4225 if (Subtarget.useNEONForFPMovs() && !isPredicated(MI) && 4226 (MI.getOpcode() == ARM::VMOVRS || MI.getOpcode() == ARM::VMOVSR || 4227 MI.getOpcode() == ARM::VMOVS)) 4228 return std::make_pair(ExeVFP, (1 << ExeVFP) | (1 << ExeNEON)); 4229 } 4230 // No other instructions can be swizzled, so just determine their domain. 4231 unsigned Domain = MI.getDesc().TSFlags & ARMII::DomainMask; 4232 4233 if (Domain & ARMII::DomainNEON) 4234 return std::make_pair(ExeNEON, 0); 4235 4236 // Certain instructions can go either way on Cortex-A8. 4237 // Treat them as NEON instructions. 4238 if ((Domain & ARMII::DomainNEONA8) && Subtarget.isCortexA8()) 4239 return std::make_pair(ExeNEON, 0); 4240 4241 if (Domain & ARMII::DomainVFP) 4242 return std::make_pair(ExeVFP, 0); 4243 4244 return std::make_pair(ExeGeneric, 0); 4245 } 4246 4247 static unsigned getCorrespondingDRegAndLane(const TargetRegisterInfo *TRI, 4248 unsigned SReg, unsigned &Lane) { 4249 unsigned DReg = TRI->getMatchingSuperReg(SReg, ARM::ssub_0, &ARM::DPRRegClass); 4250 Lane = 0; 4251 4252 if (DReg != ARM::NoRegister) 4253 return DReg; 4254 4255 Lane = 1; 4256 DReg = TRI->getMatchingSuperReg(SReg, ARM::ssub_1, &ARM::DPRRegClass); 4257 4258 assert(DReg && "S-register with no D super-register?"); 4259 return DReg; 4260 } 4261 4262 /// getImplicitSPRUseForDPRUse - Given a use of a DPR register and lane, 4263 /// set ImplicitSReg to a register number that must be marked as implicit-use or 4264 /// zero if no register needs to be defined as implicit-use. 4265 /// 4266 /// If the function cannot determine if an SPR should be marked implicit use or 4267 /// not, it returns false. 4268 /// 4269 /// This function handles cases where an instruction is being modified from taking 4270 /// an SPR to a DPR[Lane]. A use of the DPR is being added, which may conflict 4271 /// with an earlier def of an SPR corresponding to DPR[Lane^1] (i.e. the other 4272 /// lane of the DPR). 4273 /// 4274 /// If the other SPR is defined, an implicit-use of it should be added. Else, 4275 /// (including the case where the DPR itself is defined), it should not. 4276 /// 4277 static bool getImplicitSPRUseForDPRUse(const TargetRegisterInfo *TRI, 4278 MachineInstr &MI, unsigned DReg, 4279 unsigned Lane, unsigned &ImplicitSReg) { 4280 // If the DPR is defined or used already, the other SPR lane will be chained 4281 // correctly, so there is nothing to be done. 4282 if (MI.definesRegister(DReg, TRI) || MI.readsRegister(DReg, TRI)) { 4283 ImplicitSReg = 0; 4284 return true; 4285 } 4286 4287 // Otherwise we need to go searching to see if the SPR is set explicitly. 4288 ImplicitSReg = TRI->getSubReg(DReg, 4289 (Lane & 1) ? ARM::ssub_0 : ARM::ssub_1); 4290 MachineBasicBlock::LivenessQueryResult LQR = 4291 MI.getParent()->computeRegisterLiveness(TRI, ImplicitSReg, MI); 4292 4293 if (LQR == MachineBasicBlock::LQR_Live) 4294 return true; 4295 else if (LQR == MachineBasicBlock::LQR_Unknown) 4296 return false; 4297 4298 // If the register is known not to be live, there is no need to add an 4299 // implicit-use. 4300 ImplicitSReg = 0; 4301 return true; 4302 } 4303 4304 void ARMBaseInstrInfo::setExecutionDomain(MachineInstr &MI, 4305 unsigned Domain) const { 4306 unsigned DstReg, SrcReg, DReg; 4307 unsigned Lane; 4308 MachineInstrBuilder MIB(*MI.getParent()->getParent(), MI); 4309 const TargetRegisterInfo *TRI = &getRegisterInfo(); 4310 switch (MI.getOpcode()) { 4311 default: 4312 llvm_unreachable("cannot handle opcode!"); 4313 break; 4314 case ARM::VMOVD: 4315 if (Domain != ExeNEON) 4316 break; 4317 4318 // Zap the predicate operands. 4319 assert(!isPredicated(MI) && "Cannot predicate a VORRd"); 4320 4321 // Make sure we've got NEON instructions. 4322 assert(Subtarget.hasNEON() && "VORRd requires NEON"); 4323 4324 // Source instruction is %DDst = VMOVD %DSrc, 14, %noreg (; implicits) 4325 DstReg = MI.getOperand(0).getReg(); 4326 SrcReg = MI.getOperand(1).getReg(); 4327 4328 for (unsigned i = MI.getDesc().getNumOperands(); i; --i) 4329 MI.RemoveOperand(i - 1); 4330 4331 // Change to a %DDst = VORRd %DSrc, %DSrc, 14, %noreg (; implicits) 4332 MI.setDesc(get(ARM::VORRd)); 4333 AddDefaultPred( 4334 MIB.addReg(DstReg, RegState::Define).addReg(SrcReg).addReg(SrcReg)); 4335 break; 4336 case ARM::VMOVRS: 4337 if (Domain != ExeNEON) 4338 break; 4339 assert(!isPredicated(MI) && "Cannot predicate a VGETLN"); 4340 4341 // Source instruction is %RDst = VMOVRS %SSrc, 14, %noreg (; implicits) 4342 DstReg = MI.getOperand(0).getReg(); 4343 SrcReg = MI.getOperand(1).getReg(); 4344 4345 for (unsigned i = MI.getDesc().getNumOperands(); i; --i) 4346 MI.RemoveOperand(i - 1); 4347 4348 DReg = getCorrespondingDRegAndLane(TRI, SrcReg, Lane); 4349 4350 // Convert to %RDst = VGETLNi32 %DSrc, Lane, 14, %noreg (; imps) 4351 // Note that DSrc has been widened and the other lane may be undef, which 4352 // contaminates the entire register. 4353 MI.setDesc(get(ARM::VGETLNi32)); 4354 AddDefaultPred(MIB.addReg(DstReg, RegState::Define) 4355 .addReg(DReg, RegState::Undef) 4356 .addImm(Lane)); 4357 4358 // The old source should be an implicit use, otherwise we might think it 4359 // was dead before here. 4360 MIB.addReg(SrcReg, RegState::Implicit); 4361 break; 4362 case ARM::VMOVSR: { 4363 if (Domain != ExeNEON) 4364 break; 4365 assert(!isPredicated(MI) && "Cannot predicate a VSETLN"); 4366 4367 // Source instruction is %SDst = VMOVSR %RSrc, 14, %noreg (; implicits) 4368 DstReg = MI.getOperand(0).getReg(); 4369 SrcReg = MI.getOperand(1).getReg(); 4370 4371 DReg = getCorrespondingDRegAndLane(TRI, DstReg, Lane); 4372 4373 unsigned ImplicitSReg; 4374 if (!getImplicitSPRUseForDPRUse(TRI, MI, DReg, Lane, ImplicitSReg)) 4375 break; 4376 4377 for (unsigned i = MI.getDesc().getNumOperands(); i; --i) 4378 MI.RemoveOperand(i - 1); 4379 4380 // Convert to %DDst = VSETLNi32 %DDst, %RSrc, Lane, 14, %noreg (; imps) 4381 // Again DDst may be undefined at the beginning of this instruction. 4382 MI.setDesc(get(ARM::VSETLNi32)); 4383 MIB.addReg(DReg, RegState::Define) 4384 .addReg(DReg, getUndefRegState(!MI.readsRegister(DReg, TRI))) 4385 .addReg(SrcReg) 4386 .addImm(Lane); 4387 AddDefaultPred(MIB); 4388 4389 // The narrower destination must be marked as set to keep previous chains 4390 // in place. 4391 MIB.addReg(DstReg, RegState::Define | RegState::Implicit); 4392 if (ImplicitSReg != 0) 4393 MIB.addReg(ImplicitSReg, RegState::Implicit); 4394 break; 4395 } 4396 case ARM::VMOVS: { 4397 if (Domain != ExeNEON) 4398 break; 4399 4400 // Source instruction is %SDst = VMOVS %SSrc, 14, %noreg (; implicits) 4401 DstReg = MI.getOperand(0).getReg(); 4402 SrcReg = MI.getOperand(1).getReg(); 4403 4404 unsigned DstLane = 0, SrcLane = 0, DDst, DSrc; 4405 DDst = getCorrespondingDRegAndLane(TRI, DstReg, DstLane); 4406 DSrc = getCorrespondingDRegAndLane(TRI, SrcReg, SrcLane); 4407 4408 unsigned ImplicitSReg; 4409 if (!getImplicitSPRUseForDPRUse(TRI, MI, DSrc, SrcLane, ImplicitSReg)) 4410 break; 4411 4412 for (unsigned i = MI.getDesc().getNumOperands(); i; --i) 4413 MI.RemoveOperand(i - 1); 4414 4415 if (DSrc == DDst) { 4416 // Destination can be: 4417 // %DDst = VDUPLN32d %DDst, Lane, 14, %noreg (; implicits) 4418 MI.setDesc(get(ARM::VDUPLN32d)); 4419 MIB.addReg(DDst, RegState::Define) 4420 .addReg(DDst, getUndefRegState(!MI.readsRegister(DDst, TRI))) 4421 .addImm(SrcLane); 4422 AddDefaultPred(MIB); 4423 4424 // Neither the source or the destination are naturally represented any 4425 // more, so add them in manually. 4426 MIB.addReg(DstReg, RegState::Implicit | RegState::Define); 4427 MIB.addReg(SrcReg, RegState::Implicit); 4428 if (ImplicitSReg != 0) 4429 MIB.addReg(ImplicitSReg, RegState::Implicit); 4430 break; 4431 } 4432 4433 // In general there's no single instruction that can perform an S <-> S 4434 // move in NEON space, but a pair of VEXT instructions *can* do the 4435 // job. It turns out that the VEXTs needed will only use DSrc once, with 4436 // the position based purely on the combination of lane-0 and lane-1 4437 // involved. For example 4438 // vmov s0, s2 -> vext.32 d0, d0, d1, #1 vext.32 d0, d0, d0, #1 4439 // vmov s1, s3 -> vext.32 d0, d1, d0, #1 vext.32 d0, d0, d0, #1 4440 // vmov s0, s3 -> vext.32 d0, d0, d0, #1 vext.32 d0, d1, d0, #1 4441 // vmov s1, s2 -> vext.32 d0, d0, d0, #1 vext.32 d0, d0, d1, #1 4442 // 4443 // Pattern of the MachineInstrs is: 4444 // %DDst = VEXTd32 %DSrc1, %DSrc2, Lane, 14, %noreg (;implicits) 4445 MachineInstrBuilder NewMIB; 4446 NewMIB = BuildMI(*MI.getParent(), MI, MI.getDebugLoc(), get(ARM::VEXTd32), 4447 DDst); 4448 4449 // On the first instruction, both DSrc and DDst may be <undef> if present. 4450 // Specifically when the original instruction didn't have them as an 4451 // <imp-use>. 4452 unsigned CurReg = SrcLane == 1 && DstLane == 1 ? DSrc : DDst; 4453 bool CurUndef = !MI.readsRegister(CurReg, TRI); 4454 NewMIB.addReg(CurReg, getUndefRegState(CurUndef)); 4455 4456 CurReg = SrcLane == 0 && DstLane == 0 ? DSrc : DDst; 4457 CurUndef = !MI.readsRegister(CurReg, TRI); 4458 NewMIB.addReg(CurReg, getUndefRegState(CurUndef)); 4459 4460 NewMIB.addImm(1); 4461 AddDefaultPred(NewMIB); 4462 4463 if (SrcLane == DstLane) 4464 NewMIB.addReg(SrcReg, RegState::Implicit); 4465 4466 MI.setDesc(get(ARM::VEXTd32)); 4467 MIB.addReg(DDst, RegState::Define); 4468 4469 // On the second instruction, DDst has definitely been defined above, so 4470 // it is not <undef>. DSrc, if present, can be <undef> as above. 4471 CurReg = SrcLane == 1 && DstLane == 0 ? DSrc : DDst; 4472 CurUndef = CurReg == DSrc && !MI.readsRegister(CurReg, TRI); 4473 MIB.addReg(CurReg, getUndefRegState(CurUndef)); 4474 4475 CurReg = SrcLane == 0 && DstLane == 1 ? DSrc : DDst; 4476 CurUndef = CurReg == DSrc && !MI.readsRegister(CurReg, TRI); 4477 MIB.addReg(CurReg, getUndefRegState(CurUndef)); 4478 4479 MIB.addImm(1); 4480 AddDefaultPred(MIB); 4481 4482 if (SrcLane != DstLane) 4483 MIB.addReg(SrcReg, RegState::Implicit); 4484 4485 // As before, the original destination is no longer represented, add it 4486 // implicitly. 4487 MIB.addReg(DstReg, RegState::Define | RegState::Implicit); 4488 if (ImplicitSReg != 0) 4489 MIB.addReg(ImplicitSReg, RegState::Implicit); 4490 break; 4491 } 4492 } 4493 4494 } 4495 4496 //===----------------------------------------------------------------------===// 4497 // Partial register updates 4498 //===----------------------------------------------------------------------===// 4499 // 4500 // Swift renames NEON registers with 64-bit granularity. That means any 4501 // instruction writing an S-reg implicitly reads the containing D-reg. The 4502 // problem is mostly avoided by translating f32 operations to v2f32 operations 4503 // on D-registers, but f32 loads are still a problem. 4504 // 4505 // These instructions can load an f32 into a NEON register: 4506 // 4507 // VLDRS - Only writes S, partial D update. 4508 // VLD1LNd32 - Writes all D-regs, explicit partial D update, 2 uops. 4509 // VLD1DUPd32 - Writes all D-regs, no partial reg update, 2 uops. 4510 // 4511 // FCONSTD can be used as a dependency-breaking instruction. 4512 unsigned ARMBaseInstrInfo::getPartialRegUpdateClearance( 4513 const MachineInstr &MI, unsigned OpNum, 4514 const TargetRegisterInfo *TRI) const { 4515 auto PartialUpdateClearance = Subtarget.getPartialUpdateClearance(); 4516 if (!PartialUpdateClearance) 4517 return 0; 4518 4519 assert(TRI && "Need TRI instance"); 4520 4521 const MachineOperand &MO = MI.getOperand(OpNum); 4522 if (MO.readsReg()) 4523 return 0; 4524 unsigned Reg = MO.getReg(); 4525 int UseOp = -1; 4526 4527 switch (MI.getOpcode()) { 4528 // Normal instructions writing only an S-register. 4529 case ARM::VLDRS: 4530 case ARM::FCONSTS: 4531 case ARM::VMOVSR: 4532 case ARM::VMOVv8i8: 4533 case ARM::VMOVv4i16: 4534 case ARM::VMOVv2i32: 4535 case ARM::VMOVv2f32: 4536 case ARM::VMOVv1i64: 4537 UseOp = MI.findRegisterUseOperandIdx(Reg, false, TRI); 4538 break; 4539 4540 // Explicitly reads the dependency. 4541 case ARM::VLD1LNd32: 4542 UseOp = 3; 4543 break; 4544 default: 4545 return 0; 4546 } 4547 4548 // If this instruction actually reads a value from Reg, there is no unwanted 4549 // dependency. 4550 if (UseOp != -1 && MI.getOperand(UseOp).readsReg()) 4551 return 0; 4552 4553 // We must be able to clobber the whole D-reg. 4554 if (TargetRegisterInfo::isVirtualRegister(Reg)) { 4555 // Virtual register must be a foo:ssub_0<def,undef> operand. 4556 if (!MO.getSubReg() || MI.readsVirtualRegister(Reg)) 4557 return 0; 4558 } else if (ARM::SPRRegClass.contains(Reg)) { 4559 // Physical register: MI must define the full D-reg. 4560 unsigned DReg = TRI->getMatchingSuperReg(Reg, ARM::ssub_0, 4561 &ARM::DPRRegClass); 4562 if (!DReg || !MI.definesRegister(DReg, TRI)) 4563 return 0; 4564 } 4565 4566 // MI has an unwanted D-register dependency. 4567 // Avoid defs in the previous N instructrions. 4568 return PartialUpdateClearance; 4569 } 4570 4571 // Break a partial register dependency after getPartialRegUpdateClearance 4572 // returned non-zero. 4573 void ARMBaseInstrInfo::breakPartialRegDependency( 4574 MachineInstr &MI, unsigned OpNum, const TargetRegisterInfo *TRI) const { 4575 assert(OpNum < MI.getDesc().getNumDefs() && "OpNum is not a def"); 4576 assert(TRI && "Need TRI instance"); 4577 4578 const MachineOperand &MO = MI.getOperand(OpNum); 4579 unsigned Reg = MO.getReg(); 4580 assert(TargetRegisterInfo::isPhysicalRegister(Reg) && 4581 "Can't break virtual register dependencies."); 4582 unsigned DReg = Reg; 4583 4584 // If MI defines an S-reg, find the corresponding D super-register. 4585 if (ARM::SPRRegClass.contains(Reg)) { 4586 DReg = ARM::D0 + (Reg - ARM::S0) / 2; 4587 assert(TRI->isSuperRegister(Reg, DReg) && "Register enums broken"); 4588 } 4589 4590 assert(ARM::DPRRegClass.contains(DReg) && "Can only break D-reg deps"); 4591 assert(MI.definesRegister(DReg, TRI) && "MI doesn't clobber full D-reg"); 4592 4593 // FIXME: In some cases, VLDRS can be changed to a VLD1DUPd32 which defines 4594 // the full D-register by loading the same value to both lanes. The 4595 // instruction is micro-coded with 2 uops, so don't do this until we can 4596 // properly schedule micro-coded instructions. The dispatcher stalls cause 4597 // too big regressions. 4598 4599 // Insert the dependency-breaking FCONSTD before MI. 4600 // 96 is the encoding of 0.5, but the actual value doesn't matter here. 4601 AddDefaultPred( 4602 BuildMI(*MI.getParent(), MI, MI.getDebugLoc(), get(ARM::FCONSTD), DReg) 4603 .addImm(96)); 4604 MI.addRegisterKilled(DReg, TRI, true); 4605 } 4606 4607 bool ARMBaseInstrInfo::hasNOP() const { 4608 return Subtarget.getFeatureBits()[ARM::HasV6KOps]; 4609 } 4610 4611 bool ARMBaseInstrInfo::isSwiftFastImmShift(const MachineInstr *MI) const { 4612 if (MI->getNumOperands() < 4) 4613 return true; 4614 unsigned ShOpVal = MI->getOperand(3).getImm(); 4615 unsigned ShImm = ARM_AM::getSORegOffset(ShOpVal); 4616 // Swift supports faster shifts for: lsl 2, lsl 1, and lsr 1. 4617 if ((ShImm == 1 && ARM_AM::getSORegShOp(ShOpVal) == ARM_AM::lsr) || 4618 ((ShImm == 1 || ShImm == 2) && 4619 ARM_AM::getSORegShOp(ShOpVal) == ARM_AM::lsl)) 4620 return true; 4621 4622 return false; 4623 } 4624 4625 bool ARMBaseInstrInfo::getRegSequenceLikeInputs( 4626 const MachineInstr &MI, unsigned DefIdx, 4627 SmallVectorImpl<RegSubRegPairAndIdx> &InputRegs) const { 4628 assert(DefIdx < MI.getDesc().getNumDefs() && "Invalid definition index"); 4629 assert(MI.isRegSequenceLike() && "Invalid kind of instruction"); 4630 4631 switch (MI.getOpcode()) { 4632 case ARM::VMOVDRR: 4633 // dX = VMOVDRR rY, rZ 4634 // is the same as: 4635 // dX = REG_SEQUENCE rY, ssub_0, rZ, ssub_1 4636 // Populate the InputRegs accordingly. 4637 // rY 4638 const MachineOperand *MOReg = &MI.getOperand(1); 4639 InputRegs.push_back( 4640 RegSubRegPairAndIdx(MOReg->getReg(), MOReg->getSubReg(), ARM::ssub_0)); 4641 // rZ 4642 MOReg = &MI.getOperand(2); 4643 InputRegs.push_back( 4644 RegSubRegPairAndIdx(MOReg->getReg(), MOReg->getSubReg(), ARM::ssub_1)); 4645 return true; 4646 } 4647 llvm_unreachable("Target dependent opcode missing"); 4648 } 4649 4650 bool ARMBaseInstrInfo::getExtractSubregLikeInputs( 4651 const MachineInstr &MI, unsigned DefIdx, 4652 RegSubRegPairAndIdx &InputReg) const { 4653 assert(DefIdx < MI.getDesc().getNumDefs() && "Invalid definition index"); 4654 assert(MI.isExtractSubregLike() && "Invalid kind of instruction"); 4655 4656 switch (MI.getOpcode()) { 4657 case ARM::VMOVRRD: 4658 // rX, rY = VMOVRRD dZ 4659 // is the same as: 4660 // rX = EXTRACT_SUBREG dZ, ssub_0 4661 // rY = EXTRACT_SUBREG dZ, ssub_1 4662 const MachineOperand &MOReg = MI.getOperand(2); 4663 InputReg.Reg = MOReg.getReg(); 4664 InputReg.SubReg = MOReg.getSubReg(); 4665 InputReg.SubIdx = DefIdx == 0 ? ARM::ssub_0 : ARM::ssub_1; 4666 return true; 4667 } 4668 llvm_unreachable("Target dependent opcode missing"); 4669 } 4670 4671 bool ARMBaseInstrInfo::getInsertSubregLikeInputs( 4672 const MachineInstr &MI, unsigned DefIdx, RegSubRegPair &BaseReg, 4673 RegSubRegPairAndIdx &InsertedReg) const { 4674 assert(DefIdx < MI.getDesc().getNumDefs() && "Invalid definition index"); 4675 assert(MI.isInsertSubregLike() && "Invalid kind of instruction"); 4676 4677 switch (MI.getOpcode()) { 4678 case ARM::VSETLNi32: 4679 // dX = VSETLNi32 dY, rZ, imm 4680 const MachineOperand &MOBaseReg = MI.getOperand(1); 4681 const MachineOperand &MOInsertedReg = MI.getOperand(2); 4682 const MachineOperand &MOIndex = MI.getOperand(3); 4683 BaseReg.Reg = MOBaseReg.getReg(); 4684 BaseReg.SubReg = MOBaseReg.getSubReg(); 4685 4686 InsertedReg.Reg = MOInsertedReg.getReg(); 4687 InsertedReg.SubReg = MOInsertedReg.getSubReg(); 4688 InsertedReg.SubIdx = MOIndex.getImm() == 0 ? ARM::ssub_0 : ARM::ssub_1; 4689 return true; 4690 } 4691 llvm_unreachable("Target dependent opcode missing"); 4692 } 4693