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/IR/Constants.h" 32 #include "llvm/IR/Function.h" 33 #include "llvm/IR/GlobalValue.h" 34 #include "llvm/MC/MCAsmInfo.h" 35 #include "llvm/MC/MCExpr.h" 36 #include "llvm/Support/BranchProbability.h" 37 #include "llvm/Support/CommandLine.h" 38 #include "llvm/Support/Debug.h" 39 #include "llvm/Support/ErrorHandling.h" 40 41 using namespace llvm; 42 43 #define DEBUG_TYPE "arm-instrinfo" 44 45 #define GET_INSTRINFO_CTOR_DTOR 46 #include "ARMGenInstrInfo.inc" 47 48 static cl::opt<bool> 49 EnableARM3Addr("enable-arm-3-addr-conv", cl::Hidden, 50 cl::desc("Enable ARM 2-addr to 3-addr conv")); 51 52 static cl::opt<bool> 53 WidenVMOVS("widen-vmovs", cl::Hidden, cl::init(true), 54 cl::desc("Widen ARM vmovs to vmovd when possible")); 55 56 static cl::opt<unsigned> 57 SwiftPartialUpdateClearance("swift-partial-update-clearance", 58 cl::Hidden, cl::init(12), 59 cl::desc("Clearance before partial register updates")); 60 61 /// ARM_MLxEntry - Record information about MLA / MLS instructions. 62 struct ARM_MLxEntry { 63 uint16_t MLxOpc; // MLA / MLS opcode 64 uint16_t MulOpc; // Expanded multiplication opcode 65 uint16_t AddSubOpc; // Expanded add / sub opcode 66 bool NegAcc; // True if the acc is negated before the add / sub. 67 bool HasLane; // True if instruction has an extra "lane" operand. 68 }; 69 70 static const ARM_MLxEntry ARM_MLxTable[] = { 71 // MLxOpc, MulOpc, AddSubOpc, NegAcc, HasLane 72 // fp scalar ops 73 { ARM::VMLAS, ARM::VMULS, ARM::VADDS, false, false }, 74 { ARM::VMLSS, ARM::VMULS, ARM::VSUBS, false, false }, 75 { ARM::VMLAD, ARM::VMULD, ARM::VADDD, false, false }, 76 { ARM::VMLSD, ARM::VMULD, ARM::VSUBD, false, false }, 77 { ARM::VNMLAS, ARM::VNMULS, ARM::VSUBS, true, false }, 78 { ARM::VNMLSS, ARM::VMULS, ARM::VSUBS, true, false }, 79 { ARM::VNMLAD, ARM::VNMULD, ARM::VSUBD, true, false }, 80 { ARM::VNMLSD, ARM::VMULD, ARM::VSUBD, true, false }, 81 82 // fp SIMD ops 83 { ARM::VMLAfd, ARM::VMULfd, ARM::VADDfd, false, false }, 84 { ARM::VMLSfd, ARM::VMULfd, ARM::VSUBfd, false, false }, 85 { ARM::VMLAfq, ARM::VMULfq, ARM::VADDfq, false, false }, 86 { ARM::VMLSfq, ARM::VMULfq, ARM::VSUBfq, false, false }, 87 { ARM::VMLAslfd, ARM::VMULslfd, ARM::VADDfd, false, true }, 88 { ARM::VMLSslfd, ARM::VMULslfd, ARM::VSUBfd, false, true }, 89 { ARM::VMLAslfq, ARM::VMULslfq, ARM::VADDfq, false, true }, 90 { ARM::VMLSslfq, ARM::VMULslfq, ARM::VSUBfq, false, true }, 91 }; 92 93 ARMBaseInstrInfo::ARMBaseInstrInfo(const ARMSubtarget& STI) 94 : ARMGenInstrInfo(ARM::ADJCALLSTACKDOWN, ARM::ADJCALLSTACKUP), 95 Subtarget(STI) { 96 for (unsigned i = 0, e = array_lengthof(ARM_MLxTable); i != e; ++i) { 97 if (!MLxEntryMap.insert(std::make_pair(ARM_MLxTable[i].MLxOpc, i)).second) 98 assert(false && "Duplicated entries?"); 99 MLxHazardOpcodes.insert(ARM_MLxTable[i].AddSubOpc); 100 MLxHazardOpcodes.insert(ARM_MLxTable[i].MulOpc); 101 } 102 } 103 104 // Use a ScoreboardHazardRecognizer for prepass ARM scheduling. TargetInstrImpl 105 // currently defaults to no prepass hazard recognizer. 106 ScheduleHazardRecognizer * 107 ARMBaseInstrInfo::CreateTargetHazardRecognizer(const TargetSubtargetInfo *STI, 108 const ScheduleDAG *DAG) const { 109 if (usePreRAHazardRecognizer()) { 110 const InstrItineraryData *II = 111 static_cast<const ARMSubtarget *>(STI)->getInstrItineraryData(); 112 return new ScoreboardHazardRecognizer(II, DAG, "pre-RA-sched"); 113 } 114 return TargetInstrInfo::CreateTargetHazardRecognizer(STI, DAG); 115 } 116 117 ScheduleHazardRecognizer *ARMBaseInstrInfo:: 118 CreateTargetPostRAHazardRecognizer(const InstrItineraryData *II, 119 const ScheduleDAG *DAG) const { 120 if (Subtarget.isThumb2() || Subtarget.hasVFP2()) 121 return (ScheduleHazardRecognizer *)new ARMHazardRecognizer(II, DAG); 122 return TargetInstrInfo::CreateTargetPostRAHazardRecognizer(II, DAG); 123 } 124 125 MachineInstr * 126 ARMBaseInstrInfo::convertToThreeAddress(MachineFunction::iterator &MFI, 127 MachineBasicBlock::iterator &MBBI, 128 LiveVariables *LV) const { 129 // FIXME: Thumb2 support. 130 131 if (!EnableARM3Addr) 132 return nullptr; 133 134 MachineInstr *MI = MBBI; 135 MachineFunction &MF = *MI->getParent()->getParent(); 136 uint64_t TSFlags = MI->getDesc().TSFlags; 137 bool isPre = false; 138 switch ((TSFlags & ARMII::IndexModeMask) >> ARMII::IndexModeShift) { 139 default: return nullptr; 140 case ARMII::IndexModePre: 141 isPre = true; 142 break; 143 case ARMII::IndexModePost: 144 break; 145 } 146 147 // Try splitting an indexed load/store to an un-indexed one plus an add/sub 148 // operation. 149 unsigned MemOpc = getUnindexedOpcode(MI->getOpcode()); 150 if (MemOpc == 0) 151 return nullptr; 152 153 MachineInstr *UpdateMI = nullptr; 154 MachineInstr *MemMI = nullptr; 155 unsigned AddrMode = (TSFlags & ARMII::AddrModeMask); 156 const MCInstrDesc &MCID = MI->getDesc(); 157 unsigned NumOps = MCID.getNumOperands(); 158 bool isLoad = !MI->mayStore(); 159 const MachineOperand &WB = isLoad ? MI->getOperand(1) : MI->getOperand(0); 160 const MachineOperand &Base = MI->getOperand(2); 161 const MachineOperand &Offset = MI->getOperand(NumOps-3); 162 unsigned WBReg = WB.getReg(); 163 unsigned BaseReg = Base.getReg(); 164 unsigned OffReg = Offset.getReg(); 165 unsigned OffImm = MI->getOperand(NumOps-2).getImm(); 166 ARMCC::CondCodes Pred = (ARMCC::CondCodes)MI->getOperand(NumOps-1).getImm(); 167 switch (AddrMode) { 168 default: llvm_unreachable("Unknown indexed op!"); 169 case ARMII::AddrMode2: { 170 bool isSub = ARM_AM::getAM2Op(OffImm) == ARM_AM::sub; 171 unsigned Amt = ARM_AM::getAM2Offset(OffImm); 172 if (OffReg == 0) { 173 if (ARM_AM::getSOImmVal(Amt) == -1) 174 // Can't encode it in a so_imm operand. This transformation will 175 // add more than 1 instruction. Abandon! 176 return nullptr; 177 UpdateMI = BuildMI(MF, MI->getDebugLoc(), 178 get(isSub ? ARM::SUBri : ARM::ADDri), WBReg) 179 .addReg(BaseReg).addImm(Amt) 180 .addImm(Pred).addReg(0).addReg(0); 181 } else if (Amt != 0) { 182 ARM_AM::ShiftOpc ShOpc = ARM_AM::getAM2ShiftOpc(OffImm); 183 unsigned SOOpc = ARM_AM::getSORegOpc(ShOpc, Amt); 184 UpdateMI = BuildMI(MF, MI->getDebugLoc(), 185 get(isSub ? ARM::SUBrsi : ARM::ADDrsi), WBReg) 186 .addReg(BaseReg).addReg(OffReg).addReg(0).addImm(SOOpc) 187 .addImm(Pred).addReg(0).addReg(0); 188 } else 189 UpdateMI = BuildMI(MF, MI->getDebugLoc(), 190 get(isSub ? ARM::SUBrr : ARM::ADDrr), WBReg) 191 .addReg(BaseReg).addReg(OffReg) 192 .addImm(Pred).addReg(0).addReg(0); 193 break; 194 } 195 case ARMII::AddrMode3 : { 196 bool isSub = ARM_AM::getAM3Op(OffImm) == ARM_AM::sub; 197 unsigned Amt = ARM_AM::getAM3Offset(OffImm); 198 if (OffReg == 0) 199 // Immediate is 8-bits. It's guaranteed to fit in a so_imm operand. 200 UpdateMI = BuildMI(MF, MI->getDebugLoc(), 201 get(isSub ? ARM::SUBri : ARM::ADDri), WBReg) 202 .addReg(BaseReg).addImm(Amt) 203 .addImm(Pred).addReg(0).addReg(0); 204 else 205 UpdateMI = BuildMI(MF, MI->getDebugLoc(), 206 get(isSub ? ARM::SUBrr : ARM::ADDrr), WBReg) 207 .addReg(BaseReg).addReg(OffReg) 208 .addImm(Pred).addReg(0).addReg(0); 209 break; 210 } 211 } 212 213 std::vector<MachineInstr*> NewMIs; 214 if (isPre) { 215 if (isLoad) 216 MemMI = BuildMI(MF, MI->getDebugLoc(), 217 get(MemOpc), MI->getOperand(0).getReg()) 218 .addReg(WBReg).addImm(0).addImm(Pred); 219 else 220 MemMI = BuildMI(MF, MI->getDebugLoc(), 221 get(MemOpc)).addReg(MI->getOperand(1).getReg()) 222 .addReg(WBReg).addReg(0).addImm(0).addImm(Pred); 223 NewMIs.push_back(MemMI); 224 NewMIs.push_back(UpdateMI); 225 } else { 226 if (isLoad) 227 MemMI = BuildMI(MF, MI->getDebugLoc(), 228 get(MemOpc), MI->getOperand(0).getReg()) 229 .addReg(BaseReg).addImm(0).addImm(Pred); 230 else 231 MemMI = BuildMI(MF, MI->getDebugLoc(), 232 get(MemOpc)).addReg(MI->getOperand(1).getReg()) 233 .addReg(BaseReg).addReg(0).addImm(0).addImm(Pred); 234 if (WB.isDead()) 235 UpdateMI->getOperand(0).setIsDead(); 236 NewMIs.push_back(UpdateMI); 237 NewMIs.push_back(MemMI); 238 } 239 240 // Transfer LiveVariables states, kill / dead info. 241 if (LV) { 242 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) { 243 MachineOperand &MO = MI->getOperand(i); 244 if (MO.isReg() && TargetRegisterInfo::isVirtualRegister(MO.getReg())) { 245 unsigned Reg = MO.getReg(); 246 247 LiveVariables::VarInfo &VI = LV->getVarInfo(Reg); 248 if (MO.isDef()) { 249 MachineInstr *NewMI = (Reg == WBReg) ? UpdateMI : MemMI; 250 if (MO.isDead()) 251 LV->addVirtualRegisterDead(Reg, NewMI); 252 } 253 if (MO.isUse() && MO.isKill()) { 254 for (unsigned j = 0; j < 2; ++j) { 255 // Look at the two new MI's in reverse order. 256 MachineInstr *NewMI = NewMIs[j]; 257 if (!NewMI->readsRegister(Reg)) 258 continue; 259 LV->addVirtualRegisterKilled(Reg, NewMI); 260 if (VI.removeKill(MI)) 261 VI.Kills.push_back(NewMI); 262 break; 263 } 264 } 265 } 266 } 267 } 268 269 MFI->insert(MBBI, NewMIs[1]); 270 MFI->insert(MBBI, NewMIs[0]); 271 return NewMIs[0]; 272 } 273 274 // Branch analysis. 275 bool 276 ARMBaseInstrInfo::AnalyzeBranch(MachineBasicBlock &MBB,MachineBasicBlock *&TBB, 277 MachineBasicBlock *&FBB, 278 SmallVectorImpl<MachineOperand> &Cond, 279 bool AllowModify) const { 280 TBB = nullptr; 281 FBB = nullptr; 282 283 MachineBasicBlock::iterator I = MBB.end(); 284 if (I == MBB.begin()) 285 return false; // Empty blocks are easy. 286 --I; 287 288 // Walk backwards from the end of the basic block until the branch is 289 // analyzed or we give up. 290 while (isPredicated(I) || I->isTerminator() || I->isDebugValue()) { 291 292 // Flag to be raised on unanalyzeable instructions. This is useful in cases 293 // where we want to clean up on the end of the basic block before we bail 294 // out. 295 bool CantAnalyze = false; 296 297 // Skip over DEBUG values and predicated nonterminators. 298 while (I->isDebugValue() || !I->isTerminator()) { 299 if (I == MBB.begin()) 300 return false; 301 --I; 302 } 303 304 if (isIndirectBranchOpcode(I->getOpcode()) || 305 isJumpTableBranchOpcode(I->getOpcode())) { 306 // Indirect branches and jump tables can't be analyzed, but we still want 307 // to clean up any instructions at the tail of the basic block. 308 CantAnalyze = true; 309 } else if (isUncondBranchOpcode(I->getOpcode())) { 310 TBB = I->getOperand(0).getMBB(); 311 } else if (isCondBranchOpcode(I->getOpcode())) { 312 // Bail out if we encounter multiple conditional branches. 313 if (!Cond.empty()) 314 return true; 315 316 assert(!FBB && "FBB should have been null."); 317 FBB = TBB; 318 TBB = I->getOperand(0).getMBB(); 319 Cond.push_back(I->getOperand(1)); 320 Cond.push_back(I->getOperand(2)); 321 } else if (I->isReturn()) { 322 // Returns can't be analyzed, but we should run cleanup. 323 CantAnalyze = !isPredicated(I); 324 } else { 325 // We encountered other unrecognized terminator. Bail out immediately. 326 return true; 327 } 328 329 // Cleanup code - to be run for unpredicated unconditional branches and 330 // returns. 331 if (!isPredicated(I) && 332 (isUncondBranchOpcode(I->getOpcode()) || 333 isIndirectBranchOpcode(I->getOpcode()) || 334 isJumpTableBranchOpcode(I->getOpcode()) || 335 I->isReturn())) { 336 // Forget any previous condition branch information - it no longer applies. 337 Cond.clear(); 338 FBB = nullptr; 339 340 // If we can modify the function, delete everything below this 341 // unconditional branch. 342 if (AllowModify) { 343 MachineBasicBlock::iterator DI = std::next(I); 344 while (DI != MBB.end()) { 345 MachineInstr *InstToDelete = DI; 346 ++DI; 347 InstToDelete->eraseFromParent(); 348 } 349 } 350 } 351 352 if (CantAnalyze) 353 return true; 354 355 if (I == MBB.begin()) 356 return false; 357 358 --I; 359 } 360 361 // We made it past the terminators without bailing out - we must have 362 // analyzed this branch successfully. 363 return false; 364 } 365 366 367 unsigned ARMBaseInstrInfo::RemoveBranch(MachineBasicBlock &MBB) const { 368 MachineBasicBlock::iterator I = MBB.end(); 369 if (I == MBB.begin()) return 0; 370 --I; 371 while (I->isDebugValue()) { 372 if (I == MBB.begin()) 373 return 0; 374 --I; 375 } 376 if (!isUncondBranchOpcode(I->getOpcode()) && 377 !isCondBranchOpcode(I->getOpcode())) 378 return 0; 379 380 // Remove the branch. 381 I->eraseFromParent(); 382 383 I = MBB.end(); 384 385 if (I == MBB.begin()) return 1; 386 --I; 387 if (!isCondBranchOpcode(I->getOpcode())) 388 return 1; 389 390 // Remove the branch. 391 I->eraseFromParent(); 392 return 2; 393 } 394 395 unsigned 396 ARMBaseInstrInfo::InsertBranch(MachineBasicBlock &MBB, MachineBasicBlock *TBB, 397 MachineBasicBlock *FBB, 398 const SmallVectorImpl<MachineOperand> &Cond, 399 DebugLoc DL) const { 400 ARMFunctionInfo *AFI = MBB.getParent()->getInfo<ARMFunctionInfo>(); 401 int BOpc = !AFI->isThumbFunction() 402 ? ARM::B : (AFI->isThumb2Function() ? ARM::t2B : ARM::tB); 403 int BccOpc = !AFI->isThumbFunction() 404 ? ARM::Bcc : (AFI->isThumb2Function() ? ARM::t2Bcc : ARM::tBcc); 405 bool isThumb = AFI->isThumbFunction() || AFI->isThumb2Function(); 406 407 // Shouldn't be a fall through. 408 assert(TBB && "InsertBranch must not be told to insert a fallthrough"); 409 assert((Cond.size() == 2 || Cond.size() == 0) && 410 "ARM branch conditions have two components!"); 411 412 if (!FBB) { 413 if (Cond.empty()) { // Unconditional branch? 414 if (isThumb) 415 BuildMI(&MBB, DL, get(BOpc)).addMBB(TBB).addImm(ARMCC::AL).addReg(0); 416 else 417 BuildMI(&MBB, DL, get(BOpc)).addMBB(TBB); 418 } else 419 BuildMI(&MBB, DL, get(BccOpc)).addMBB(TBB) 420 .addImm(Cond[0].getImm()).addReg(Cond[1].getReg()); 421 return 1; 422 } 423 424 // Two-way conditional branch. 425 BuildMI(&MBB, DL, get(BccOpc)).addMBB(TBB) 426 .addImm(Cond[0].getImm()).addReg(Cond[1].getReg()); 427 if (isThumb) 428 BuildMI(&MBB, DL, get(BOpc)).addMBB(FBB).addImm(ARMCC::AL).addReg(0); 429 else 430 BuildMI(&MBB, DL, get(BOpc)).addMBB(FBB); 431 return 2; 432 } 433 434 bool ARMBaseInstrInfo:: 435 ReverseBranchCondition(SmallVectorImpl<MachineOperand> &Cond) const { 436 ARMCC::CondCodes CC = (ARMCC::CondCodes)(int)Cond[0].getImm(); 437 Cond[0].setImm(ARMCC::getOppositeCondition(CC)); 438 return false; 439 } 440 441 bool ARMBaseInstrInfo::isPredicated(const MachineInstr *MI) const { 442 if (MI->isBundle()) { 443 MachineBasicBlock::const_instr_iterator I = MI; 444 MachineBasicBlock::const_instr_iterator E = MI->getParent()->instr_end(); 445 while (++I != E && I->isInsideBundle()) { 446 int PIdx = I->findFirstPredOperandIdx(); 447 if (PIdx != -1 && I->getOperand(PIdx).getImm() != ARMCC::AL) 448 return true; 449 } 450 return false; 451 } 452 453 int PIdx = MI->findFirstPredOperandIdx(); 454 return PIdx != -1 && MI->getOperand(PIdx).getImm() != ARMCC::AL; 455 } 456 457 bool ARMBaseInstrInfo:: 458 PredicateInstruction(MachineInstr *MI, 459 const SmallVectorImpl<MachineOperand> &Pred) const { 460 unsigned Opc = MI->getOpcode(); 461 if (isUncondBranchOpcode(Opc)) { 462 MI->setDesc(get(getMatchingCondBranchOpcode(Opc))); 463 MachineInstrBuilder(*MI->getParent()->getParent(), MI) 464 .addImm(Pred[0].getImm()) 465 .addReg(Pred[1].getReg()); 466 return true; 467 } 468 469 int PIdx = MI->findFirstPredOperandIdx(); 470 if (PIdx != -1) { 471 MachineOperand &PMO = MI->getOperand(PIdx); 472 PMO.setImm(Pred[0].getImm()); 473 MI->getOperand(PIdx+1).setReg(Pred[1].getReg()); 474 return true; 475 } 476 return false; 477 } 478 479 bool ARMBaseInstrInfo:: 480 SubsumesPredicate(const SmallVectorImpl<MachineOperand> &Pred1, 481 const SmallVectorImpl<MachineOperand> &Pred2) const { 482 if (Pred1.size() > 2 || Pred2.size() > 2) 483 return false; 484 485 ARMCC::CondCodes CC1 = (ARMCC::CondCodes)Pred1[0].getImm(); 486 ARMCC::CondCodes CC2 = (ARMCC::CondCodes)Pred2[0].getImm(); 487 if (CC1 == CC2) 488 return true; 489 490 switch (CC1) { 491 default: 492 return false; 493 case ARMCC::AL: 494 return true; 495 case ARMCC::HS: 496 return CC2 == ARMCC::HI; 497 case ARMCC::LS: 498 return CC2 == ARMCC::LO || CC2 == ARMCC::EQ; 499 case ARMCC::GE: 500 return CC2 == ARMCC::GT; 501 case ARMCC::LE: 502 return CC2 == ARMCC::LT; 503 } 504 } 505 506 bool ARMBaseInstrInfo::DefinesPredicate(MachineInstr *MI, 507 std::vector<MachineOperand> &Pred) const { 508 bool Found = false; 509 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) { 510 const MachineOperand &MO = MI->getOperand(i); 511 if ((MO.isRegMask() && MO.clobbersPhysReg(ARM::CPSR)) || 512 (MO.isReg() && MO.isDef() && MO.getReg() == ARM::CPSR)) { 513 Pred.push_back(MO); 514 Found = true; 515 } 516 } 517 518 return Found; 519 } 520 521 static bool isCPSRDefined(const MachineInstr *MI) { 522 for (const auto &MO : MI->operands()) 523 if (MO.isReg() && MO.getReg() == ARM::CPSR && MO.isDef()) 524 return true; 525 return false; 526 } 527 528 static bool isEligibleForITBlock(const MachineInstr *MI) { 529 switch (MI->getOpcode()) { 530 default: return true; 531 case ARM::tADC: // ADC (register) T1 532 case ARM::tADDi3: // ADD (immediate) T1 533 case ARM::tADDi8: // ADD (immediate) T2 534 case ARM::tADDrr: // ADD (register) T1 535 case ARM::tAND: // AND (register) T1 536 case ARM::tASRri: // ASR (immediate) T1 537 case ARM::tASRrr: // ASR (register) T1 538 case ARM::tBIC: // BIC (register) T1 539 case ARM::tEOR: // EOR (register) T1 540 case ARM::tLSLri: // LSL (immediate) T1 541 case ARM::tLSLrr: // LSL (register) T1 542 case ARM::tLSRri: // LSR (immediate) T1 543 case ARM::tLSRrr: // LSR (register) T1 544 case ARM::tMUL: // MUL T1 545 case ARM::tMVN: // MVN (register) T1 546 case ARM::tORR: // ORR (register) T1 547 case ARM::tROR: // ROR (register) T1 548 case ARM::tRSB: // RSB (immediate) T1 549 case ARM::tSBC: // SBC (register) T1 550 case ARM::tSUBi3: // SUB (immediate) T1 551 case ARM::tSUBi8: // SUB (immediate) T2 552 case ARM::tSUBrr: // SUB (register) T1 553 return !isCPSRDefined(MI); 554 } 555 } 556 557 /// isPredicable - Return true if the specified instruction can be predicated. 558 /// By default, this returns true for every instruction with a 559 /// PredicateOperand. 560 bool ARMBaseInstrInfo::isPredicable(MachineInstr *MI) const { 561 if (!MI->isPredicable()) 562 return false; 563 564 if (!isEligibleForITBlock(MI)) 565 return false; 566 567 ARMFunctionInfo *AFI = 568 MI->getParent()->getParent()->getInfo<ARMFunctionInfo>(); 569 570 if (AFI->isThumb2Function()) { 571 if (getSubtarget().restrictIT()) 572 return isV8EligibleForIT(MI); 573 } else { // non-Thumb 574 if ((MI->getDesc().TSFlags & ARMII::DomainMask) == ARMII::DomainNEON) 575 return false; 576 } 577 578 return true; 579 } 580 581 namespace llvm { 582 template <> bool IsCPSRDead<MachineInstr>(MachineInstr *MI) { 583 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) { 584 const MachineOperand &MO = MI->getOperand(i); 585 if (!MO.isReg() || MO.isUndef() || MO.isUse()) 586 continue; 587 if (MO.getReg() != ARM::CPSR) 588 continue; 589 if (!MO.isDead()) 590 return false; 591 } 592 // all definitions of CPSR are dead 593 return true; 594 } 595 } 596 597 /// GetInstSize - Return the size of the specified MachineInstr. 598 /// 599 unsigned ARMBaseInstrInfo::GetInstSizeInBytes(const MachineInstr *MI) const { 600 const MachineBasicBlock &MBB = *MI->getParent(); 601 const MachineFunction *MF = MBB.getParent(); 602 const MCAsmInfo *MAI = MF->getTarget().getMCAsmInfo(); 603 604 const MCInstrDesc &MCID = MI->getDesc(); 605 if (MCID.getSize()) 606 return MCID.getSize(); 607 608 // If this machine instr is an inline asm, measure it. 609 if (MI->getOpcode() == ARM::INLINEASM) 610 return getInlineAsmLength(MI->getOperand(0).getSymbolName(), *MAI); 611 unsigned Opc = MI->getOpcode(); 612 switch (Opc) { 613 default: 614 // pseudo-instruction sizes are zero. 615 return 0; 616 case TargetOpcode::BUNDLE: 617 return getInstBundleLength(MI); 618 case ARM::MOVi16_ga_pcrel: 619 case ARM::MOVTi16_ga_pcrel: 620 case ARM::t2MOVi16_ga_pcrel: 621 case ARM::t2MOVTi16_ga_pcrel: 622 return 4; 623 case ARM::MOVi32imm: 624 case ARM::t2MOVi32imm: 625 return 8; 626 case ARM::CONSTPOOL_ENTRY: 627 // If this machine instr is a constant pool entry, its size is recorded as 628 // operand #2. 629 return MI->getOperand(2).getImm(); 630 case ARM::Int_eh_sjlj_longjmp: 631 return 16; 632 case ARM::tInt_eh_sjlj_longjmp: 633 return 10; 634 case ARM::Int_eh_sjlj_setjmp: 635 case ARM::Int_eh_sjlj_setjmp_nofp: 636 return 20; 637 case ARM::tInt_eh_sjlj_setjmp: 638 case ARM::t2Int_eh_sjlj_setjmp: 639 case ARM::t2Int_eh_sjlj_setjmp_nofp: 640 return 12; 641 case ARM::BR_JTr: 642 case ARM::BR_JTm: 643 case ARM::BR_JTadd: 644 case ARM::tBR_JTr: 645 case ARM::t2BR_JT: 646 case ARM::t2TBB_JT: 647 case ARM::t2TBH_JT: { 648 // These are jumptable branches, i.e. a branch followed by an inlined 649 // jumptable. The size is 4 + 4 * number of entries. For TBB, each 650 // entry is one byte; TBH two byte each. 651 unsigned EntrySize = (Opc == ARM::t2TBB_JT) 652 ? 1 : ((Opc == ARM::t2TBH_JT) ? 2 : 4); 653 unsigned NumOps = MCID.getNumOperands(); 654 MachineOperand JTOP = 655 MI->getOperand(NumOps - (MI->isPredicable() ? 3 : 2)); 656 unsigned JTI = JTOP.getIndex(); 657 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo(); 658 assert(MJTI != nullptr); 659 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables(); 660 assert(JTI < JT.size()); 661 // Thumb instructions are 2 byte aligned, but JT entries are 4 byte 662 // 4 aligned. The assembler / linker may add 2 byte padding just before 663 // the JT entries. The size does not include this padding; the 664 // constant islands pass does separate bookkeeping for it. 665 // FIXME: If we know the size of the function is less than (1 << 16) *2 666 // bytes, we can use 16-bit entries instead. Then there won't be an 667 // alignment issue. 668 unsigned InstSize = (Opc == ARM::tBR_JTr || Opc == ARM::t2BR_JT) ? 2 : 4; 669 unsigned NumEntries = JT[JTI].MBBs.size(); 670 if (Opc == ARM::t2TBB_JT && (NumEntries & 1)) 671 // Make sure the instruction that follows TBB is 2-byte aligned. 672 // FIXME: Constant island pass should insert an "ALIGN" instruction 673 // instead. 674 ++NumEntries; 675 return NumEntries * EntrySize + InstSize; 676 } 677 case ARM::SPACE: 678 return MI->getOperand(1).getImm(); 679 } 680 } 681 682 unsigned ARMBaseInstrInfo::getInstBundleLength(const MachineInstr *MI) const { 683 unsigned Size = 0; 684 MachineBasicBlock::const_instr_iterator I = MI; 685 MachineBasicBlock::const_instr_iterator E = MI->getParent()->instr_end(); 686 while (++I != E && I->isInsideBundle()) { 687 assert(!I->isBundle() && "No nested bundle!"); 688 Size += GetInstSizeInBytes(&*I); 689 } 690 return Size; 691 } 692 693 void ARMBaseInstrInfo::copyFromCPSR(MachineBasicBlock &MBB, 694 MachineBasicBlock::iterator I, 695 unsigned DestReg, bool KillSrc, 696 const ARMSubtarget &Subtarget) const { 697 unsigned Opc = Subtarget.isThumb() 698 ? (Subtarget.isMClass() ? ARM::t2MRS_M : ARM::t2MRS_AR) 699 : ARM::MRS; 700 701 MachineInstrBuilder MIB = 702 BuildMI(MBB, I, I->getDebugLoc(), get(Opc), DestReg); 703 704 // There is only 1 A/R class MRS instruction, and it always refers to 705 // APSR. However, there are lots of other possibilities on M-class cores. 706 if (Subtarget.isMClass()) 707 MIB.addImm(0x800); 708 709 AddDefaultPred(MIB); 710 711 MIB.addReg(ARM::CPSR, RegState::Implicit | getKillRegState(KillSrc)); 712 } 713 714 void ARMBaseInstrInfo::copyToCPSR(MachineBasicBlock &MBB, 715 MachineBasicBlock::iterator I, 716 unsigned SrcReg, bool KillSrc, 717 const ARMSubtarget &Subtarget) const { 718 unsigned Opc = Subtarget.isThumb() 719 ? (Subtarget.isMClass() ? ARM::t2MSR_M : ARM::t2MSR_AR) 720 : ARM::MSR; 721 722 MachineInstrBuilder MIB = BuildMI(MBB, I, I->getDebugLoc(), get(Opc)); 723 724 if (Subtarget.isMClass()) 725 MIB.addImm(0x800); 726 else 727 MIB.addImm(8); 728 729 MIB.addReg(SrcReg, getKillRegState(KillSrc)); 730 731 AddDefaultPred(MIB); 732 733 MIB.addReg(ARM::CPSR, RegState::Implicit | RegState::Define); 734 } 735 736 void ARMBaseInstrInfo::copyPhysReg(MachineBasicBlock &MBB, 737 MachineBasicBlock::iterator I, DebugLoc DL, 738 unsigned DestReg, unsigned SrcReg, 739 bool KillSrc) const { 740 bool GPRDest = ARM::GPRRegClass.contains(DestReg); 741 bool GPRSrc = ARM::GPRRegClass.contains(SrcReg); 742 743 if (GPRDest && GPRSrc) { 744 AddDefaultCC(AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::MOVr), DestReg) 745 .addReg(SrcReg, getKillRegState(KillSrc)))); 746 return; 747 } 748 749 bool SPRDest = ARM::SPRRegClass.contains(DestReg); 750 bool SPRSrc = ARM::SPRRegClass.contains(SrcReg); 751 752 unsigned Opc = 0; 753 if (SPRDest && SPRSrc) 754 Opc = ARM::VMOVS; 755 else if (GPRDest && SPRSrc) 756 Opc = ARM::VMOVRS; 757 else if (SPRDest && GPRSrc) 758 Opc = ARM::VMOVSR; 759 else if (ARM::DPRRegClass.contains(DestReg, SrcReg) && !Subtarget.isFPOnlySP()) 760 Opc = ARM::VMOVD; 761 else if (ARM::QPRRegClass.contains(DestReg, SrcReg)) 762 Opc = ARM::VORRq; 763 764 if (Opc) { 765 MachineInstrBuilder MIB = BuildMI(MBB, I, DL, get(Opc), DestReg); 766 MIB.addReg(SrcReg, getKillRegState(KillSrc)); 767 if (Opc == ARM::VORRq) 768 MIB.addReg(SrcReg, getKillRegState(KillSrc)); 769 AddDefaultPred(MIB); 770 return; 771 } 772 773 // Handle register classes that require multiple instructions. 774 unsigned BeginIdx = 0; 775 unsigned SubRegs = 0; 776 int Spacing = 1; 777 778 // Use VORRq when possible. 779 if (ARM::QQPRRegClass.contains(DestReg, SrcReg)) { 780 Opc = ARM::VORRq; 781 BeginIdx = ARM::qsub_0; 782 SubRegs = 2; 783 } else if (ARM::QQQQPRRegClass.contains(DestReg, SrcReg)) { 784 Opc = ARM::VORRq; 785 BeginIdx = ARM::qsub_0; 786 SubRegs = 4; 787 // Fall back to VMOVD. 788 } else if (ARM::DPairRegClass.contains(DestReg, SrcReg)) { 789 Opc = ARM::VMOVD; 790 BeginIdx = ARM::dsub_0; 791 SubRegs = 2; 792 } else if (ARM::DTripleRegClass.contains(DestReg, SrcReg)) { 793 Opc = ARM::VMOVD; 794 BeginIdx = ARM::dsub_0; 795 SubRegs = 3; 796 } else if (ARM::DQuadRegClass.contains(DestReg, SrcReg)) { 797 Opc = ARM::VMOVD; 798 BeginIdx = ARM::dsub_0; 799 SubRegs = 4; 800 } else if (ARM::GPRPairRegClass.contains(DestReg, SrcReg)) { 801 Opc = Subtarget.isThumb2() ? ARM::tMOVr : ARM::MOVr; 802 BeginIdx = ARM::gsub_0; 803 SubRegs = 2; 804 } else if (ARM::DPairSpcRegClass.contains(DestReg, SrcReg)) { 805 Opc = ARM::VMOVD; 806 BeginIdx = ARM::dsub_0; 807 SubRegs = 2; 808 Spacing = 2; 809 } else if (ARM::DTripleSpcRegClass.contains(DestReg, SrcReg)) { 810 Opc = ARM::VMOVD; 811 BeginIdx = ARM::dsub_0; 812 SubRegs = 3; 813 Spacing = 2; 814 } else if (ARM::DQuadSpcRegClass.contains(DestReg, SrcReg)) { 815 Opc = ARM::VMOVD; 816 BeginIdx = ARM::dsub_0; 817 SubRegs = 4; 818 Spacing = 2; 819 } else if (ARM::DPRRegClass.contains(DestReg, SrcReg) && Subtarget.isFPOnlySP()) { 820 Opc = ARM::VMOVS; 821 BeginIdx = ARM::ssub_0; 822 SubRegs = 2; 823 } else if (SrcReg == ARM::CPSR) { 824 copyFromCPSR(MBB, I, DestReg, KillSrc, Subtarget); 825 return; 826 } else if (DestReg == ARM::CPSR) { 827 copyToCPSR(MBB, I, SrcReg, KillSrc, Subtarget); 828 return; 829 } 830 831 assert(Opc && "Impossible reg-to-reg copy"); 832 833 const TargetRegisterInfo *TRI = &getRegisterInfo(); 834 MachineInstrBuilder Mov; 835 836 // Copy register tuples backward when the first Dest reg overlaps with SrcReg. 837 if (TRI->regsOverlap(SrcReg, TRI->getSubReg(DestReg, BeginIdx))) { 838 BeginIdx = BeginIdx + ((SubRegs - 1) * Spacing); 839 Spacing = -Spacing; 840 } 841 #ifndef NDEBUG 842 SmallSet<unsigned, 4> DstRegs; 843 #endif 844 for (unsigned i = 0; i != SubRegs; ++i) { 845 unsigned Dst = TRI->getSubReg(DestReg, BeginIdx + i * Spacing); 846 unsigned Src = TRI->getSubReg(SrcReg, BeginIdx + i * Spacing); 847 assert(Dst && Src && "Bad sub-register"); 848 #ifndef NDEBUG 849 assert(!DstRegs.count(Src) && "destructive vector copy"); 850 DstRegs.insert(Dst); 851 #endif 852 Mov = BuildMI(MBB, I, I->getDebugLoc(), get(Opc), Dst).addReg(Src); 853 // VORR takes two source operands. 854 if (Opc == ARM::VORRq) 855 Mov.addReg(Src); 856 Mov = AddDefaultPred(Mov); 857 // MOVr can set CC. 858 if (Opc == ARM::MOVr) 859 Mov = AddDefaultCC(Mov); 860 } 861 // Add implicit super-register defs and kills to the last instruction. 862 Mov->addRegisterDefined(DestReg, TRI); 863 if (KillSrc) 864 Mov->addRegisterKilled(SrcReg, TRI); 865 } 866 867 const MachineInstrBuilder & 868 ARMBaseInstrInfo::AddDReg(MachineInstrBuilder &MIB, unsigned Reg, 869 unsigned SubIdx, unsigned State, 870 const TargetRegisterInfo *TRI) const { 871 if (!SubIdx) 872 return MIB.addReg(Reg, State); 873 874 if (TargetRegisterInfo::isPhysicalRegister(Reg)) 875 return MIB.addReg(TRI->getSubReg(Reg, SubIdx), State); 876 return MIB.addReg(Reg, State, SubIdx); 877 } 878 879 void ARMBaseInstrInfo:: 880 storeRegToStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I, 881 unsigned SrcReg, bool isKill, int FI, 882 const TargetRegisterClass *RC, 883 const TargetRegisterInfo *TRI) const { 884 DebugLoc DL; 885 if (I != MBB.end()) DL = I->getDebugLoc(); 886 MachineFunction &MF = *MBB.getParent(); 887 MachineFrameInfo &MFI = *MF.getFrameInfo(); 888 unsigned Align = MFI.getObjectAlignment(FI); 889 890 MachineMemOperand *MMO = 891 MF.getMachineMemOperand(MachinePointerInfo::getFixedStack(FI), 892 MachineMemOperand::MOStore, 893 MFI.getObjectSize(FI), 894 Align); 895 896 switch (RC->getSize()) { 897 case 4: 898 if (ARM::GPRRegClass.hasSubClassEq(RC)) { 899 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::STRi12)) 900 .addReg(SrcReg, getKillRegState(isKill)) 901 .addFrameIndex(FI).addImm(0).addMemOperand(MMO)); 902 } else if (ARM::SPRRegClass.hasSubClassEq(RC)) { 903 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTRS)) 904 .addReg(SrcReg, getKillRegState(isKill)) 905 .addFrameIndex(FI).addImm(0).addMemOperand(MMO)); 906 } else 907 llvm_unreachable("Unknown reg class!"); 908 break; 909 case 8: 910 if (ARM::DPRRegClass.hasSubClassEq(RC)) { 911 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTRD)) 912 .addReg(SrcReg, getKillRegState(isKill)) 913 .addFrameIndex(FI).addImm(0).addMemOperand(MMO)); 914 } else if (ARM::GPRPairRegClass.hasSubClassEq(RC)) { 915 if (Subtarget.hasV5TEOps()) { 916 MachineInstrBuilder MIB = BuildMI(MBB, I, DL, get(ARM::STRD)); 917 AddDReg(MIB, SrcReg, ARM::gsub_0, getKillRegState(isKill), TRI); 918 AddDReg(MIB, SrcReg, ARM::gsub_1, 0, TRI); 919 MIB.addFrameIndex(FI).addReg(0).addImm(0).addMemOperand(MMO); 920 921 AddDefaultPred(MIB); 922 } else { 923 // Fallback to STM instruction, which has existed since the dawn of 924 // time. 925 MachineInstrBuilder MIB = 926 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::STMIA)) 927 .addFrameIndex(FI).addMemOperand(MMO)); 928 AddDReg(MIB, SrcReg, ARM::gsub_0, getKillRegState(isKill), TRI); 929 AddDReg(MIB, SrcReg, ARM::gsub_1, 0, TRI); 930 } 931 } else 932 llvm_unreachable("Unknown reg class!"); 933 break; 934 case 16: 935 if (ARM::DPairRegClass.hasSubClassEq(RC)) { 936 // Use aligned spills if the stack can be realigned. 937 if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) { 938 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VST1q64)) 939 .addFrameIndex(FI).addImm(16) 940 .addReg(SrcReg, getKillRegState(isKill)) 941 .addMemOperand(MMO)); 942 } else { 943 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTMQIA)) 944 .addReg(SrcReg, getKillRegState(isKill)) 945 .addFrameIndex(FI) 946 .addMemOperand(MMO)); 947 } 948 } else 949 llvm_unreachable("Unknown reg class!"); 950 break; 951 case 24: 952 if (ARM::DTripleRegClass.hasSubClassEq(RC)) { 953 // Use aligned spills if the stack can be realigned. 954 if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) { 955 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VST1d64TPseudo)) 956 .addFrameIndex(FI).addImm(16) 957 .addReg(SrcReg, getKillRegState(isKill)) 958 .addMemOperand(MMO)); 959 } else { 960 MachineInstrBuilder MIB = 961 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTMDIA)) 962 .addFrameIndex(FI)) 963 .addMemOperand(MMO); 964 MIB = AddDReg(MIB, SrcReg, ARM::dsub_0, getKillRegState(isKill), TRI); 965 MIB = AddDReg(MIB, SrcReg, ARM::dsub_1, 0, TRI); 966 AddDReg(MIB, SrcReg, ARM::dsub_2, 0, TRI); 967 } 968 } else 969 llvm_unreachable("Unknown reg class!"); 970 break; 971 case 32: 972 if (ARM::QQPRRegClass.hasSubClassEq(RC) || ARM::DQuadRegClass.hasSubClassEq(RC)) { 973 if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) { 974 // FIXME: It's possible to only store part of the QQ register if the 975 // spilled def has a sub-register index. 976 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VST1d64QPseudo)) 977 .addFrameIndex(FI).addImm(16) 978 .addReg(SrcReg, getKillRegState(isKill)) 979 .addMemOperand(MMO)); 980 } else { 981 MachineInstrBuilder MIB = 982 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTMDIA)) 983 .addFrameIndex(FI)) 984 .addMemOperand(MMO); 985 MIB = AddDReg(MIB, SrcReg, ARM::dsub_0, getKillRegState(isKill), TRI); 986 MIB = AddDReg(MIB, SrcReg, ARM::dsub_1, 0, TRI); 987 MIB = AddDReg(MIB, SrcReg, ARM::dsub_2, 0, TRI); 988 AddDReg(MIB, SrcReg, ARM::dsub_3, 0, TRI); 989 } 990 } else 991 llvm_unreachable("Unknown reg class!"); 992 break; 993 case 64: 994 if (ARM::QQQQPRRegClass.hasSubClassEq(RC)) { 995 MachineInstrBuilder MIB = 996 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTMDIA)) 997 .addFrameIndex(FI)) 998 .addMemOperand(MMO); 999 MIB = AddDReg(MIB, SrcReg, ARM::dsub_0, getKillRegState(isKill), TRI); 1000 MIB = AddDReg(MIB, SrcReg, ARM::dsub_1, 0, TRI); 1001 MIB = AddDReg(MIB, SrcReg, ARM::dsub_2, 0, TRI); 1002 MIB = AddDReg(MIB, SrcReg, ARM::dsub_3, 0, TRI); 1003 MIB = AddDReg(MIB, SrcReg, ARM::dsub_4, 0, TRI); 1004 MIB = AddDReg(MIB, SrcReg, ARM::dsub_5, 0, TRI); 1005 MIB = AddDReg(MIB, SrcReg, ARM::dsub_6, 0, TRI); 1006 AddDReg(MIB, SrcReg, ARM::dsub_7, 0, TRI); 1007 } else 1008 llvm_unreachable("Unknown reg class!"); 1009 break; 1010 default: 1011 llvm_unreachable("Unknown reg class!"); 1012 } 1013 } 1014 1015 unsigned 1016 ARMBaseInstrInfo::isStoreToStackSlot(const MachineInstr *MI, 1017 int &FrameIndex) const { 1018 switch (MI->getOpcode()) { 1019 default: break; 1020 case ARM::STRrs: 1021 case ARM::t2STRs: // FIXME: don't use t2STRs to access frame. 1022 if (MI->getOperand(1).isFI() && 1023 MI->getOperand(2).isReg() && 1024 MI->getOperand(3).isImm() && 1025 MI->getOperand(2).getReg() == 0 && 1026 MI->getOperand(3).getImm() == 0) { 1027 FrameIndex = MI->getOperand(1).getIndex(); 1028 return MI->getOperand(0).getReg(); 1029 } 1030 break; 1031 case ARM::STRi12: 1032 case ARM::t2STRi12: 1033 case ARM::tSTRspi: 1034 case ARM::VSTRD: 1035 case ARM::VSTRS: 1036 if (MI->getOperand(1).isFI() && 1037 MI->getOperand(2).isImm() && 1038 MI->getOperand(2).getImm() == 0) { 1039 FrameIndex = MI->getOperand(1).getIndex(); 1040 return MI->getOperand(0).getReg(); 1041 } 1042 break; 1043 case ARM::VST1q64: 1044 case ARM::VST1d64TPseudo: 1045 case ARM::VST1d64QPseudo: 1046 if (MI->getOperand(0).isFI() && 1047 MI->getOperand(2).getSubReg() == 0) { 1048 FrameIndex = MI->getOperand(0).getIndex(); 1049 return MI->getOperand(2).getReg(); 1050 } 1051 break; 1052 case ARM::VSTMQIA: 1053 if (MI->getOperand(1).isFI() && 1054 MI->getOperand(0).getSubReg() == 0) { 1055 FrameIndex = MI->getOperand(1).getIndex(); 1056 return MI->getOperand(0).getReg(); 1057 } 1058 break; 1059 } 1060 1061 return 0; 1062 } 1063 1064 unsigned ARMBaseInstrInfo::isStoreToStackSlotPostFE(const MachineInstr *MI, 1065 int &FrameIndex) const { 1066 const MachineMemOperand *Dummy; 1067 return MI->mayStore() && hasStoreToStackSlot(MI, Dummy, FrameIndex); 1068 } 1069 1070 void ARMBaseInstrInfo:: 1071 loadRegFromStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I, 1072 unsigned DestReg, int FI, 1073 const TargetRegisterClass *RC, 1074 const TargetRegisterInfo *TRI) const { 1075 DebugLoc DL; 1076 if (I != MBB.end()) DL = I->getDebugLoc(); 1077 MachineFunction &MF = *MBB.getParent(); 1078 MachineFrameInfo &MFI = *MF.getFrameInfo(); 1079 unsigned Align = MFI.getObjectAlignment(FI); 1080 MachineMemOperand *MMO = 1081 MF.getMachineMemOperand( 1082 MachinePointerInfo::getFixedStack(FI), 1083 MachineMemOperand::MOLoad, 1084 MFI.getObjectSize(FI), 1085 Align); 1086 1087 switch (RC->getSize()) { 1088 case 4: 1089 if (ARM::GPRRegClass.hasSubClassEq(RC)) { 1090 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::LDRi12), DestReg) 1091 .addFrameIndex(FI).addImm(0).addMemOperand(MMO)); 1092 1093 } else if (ARM::SPRRegClass.hasSubClassEq(RC)) { 1094 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDRS), DestReg) 1095 .addFrameIndex(FI).addImm(0).addMemOperand(MMO)); 1096 } else 1097 llvm_unreachable("Unknown reg class!"); 1098 break; 1099 case 8: 1100 if (ARM::DPRRegClass.hasSubClassEq(RC)) { 1101 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDRD), DestReg) 1102 .addFrameIndex(FI).addImm(0).addMemOperand(MMO)); 1103 } else if (ARM::GPRPairRegClass.hasSubClassEq(RC)) { 1104 MachineInstrBuilder MIB; 1105 1106 if (Subtarget.hasV5TEOps()) { 1107 MIB = BuildMI(MBB, I, DL, get(ARM::LDRD)); 1108 AddDReg(MIB, DestReg, ARM::gsub_0, RegState::DefineNoRead, TRI); 1109 AddDReg(MIB, DestReg, ARM::gsub_1, RegState::DefineNoRead, TRI); 1110 MIB.addFrameIndex(FI).addReg(0).addImm(0).addMemOperand(MMO); 1111 1112 AddDefaultPred(MIB); 1113 } else { 1114 // Fallback to LDM instruction, which has existed since the dawn of 1115 // time. 1116 MIB = AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::LDMIA)) 1117 .addFrameIndex(FI).addMemOperand(MMO)); 1118 MIB = AddDReg(MIB, DestReg, ARM::gsub_0, RegState::DefineNoRead, TRI); 1119 MIB = AddDReg(MIB, DestReg, ARM::gsub_1, RegState::DefineNoRead, TRI); 1120 } 1121 1122 if (TargetRegisterInfo::isPhysicalRegister(DestReg)) 1123 MIB.addReg(DestReg, RegState::ImplicitDefine); 1124 } else 1125 llvm_unreachable("Unknown reg class!"); 1126 break; 1127 case 16: 1128 if (ARM::DPairRegClass.hasSubClassEq(RC)) { 1129 if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) { 1130 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLD1q64), DestReg) 1131 .addFrameIndex(FI).addImm(16) 1132 .addMemOperand(MMO)); 1133 } else { 1134 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDMQIA), DestReg) 1135 .addFrameIndex(FI) 1136 .addMemOperand(MMO)); 1137 } 1138 } else 1139 llvm_unreachable("Unknown reg class!"); 1140 break; 1141 case 24: 1142 if (ARM::DTripleRegClass.hasSubClassEq(RC)) { 1143 if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) { 1144 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLD1d64TPseudo), DestReg) 1145 .addFrameIndex(FI).addImm(16) 1146 .addMemOperand(MMO)); 1147 } else { 1148 MachineInstrBuilder MIB = 1149 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDMDIA)) 1150 .addFrameIndex(FI) 1151 .addMemOperand(MMO)); 1152 MIB = AddDReg(MIB, DestReg, ARM::dsub_0, RegState::DefineNoRead, TRI); 1153 MIB = AddDReg(MIB, DestReg, ARM::dsub_1, RegState::DefineNoRead, TRI); 1154 MIB = AddDReg(MIB, DestReg, ARM::dsub_2, RegState::DefineNoRead, TRI); 1155 if (TargetRegisterInfo::isPhysicalRegister(DestReg)) 1156 MIB.addReg(DestReg, RegState::ImplicitDefine); 1157 } 1158 } else 1159 llvm_unreachable("Unknown reg class!"); 1160 break; 1161 case 32: 1162 if (ARM::QQPRRegClass.hasSubClassEq(RC) || ARM::DQuadRegClass.hasSubClassEq(RC)) { 1163 if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) { 1164 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLD1d64QPseudo), DestReg) 1165 .addFrameIndex(FI).addImm(16) 1166 .addMemOperand(MMO)); 1167 } else { 1168 MachineInstrBuilder MIB = 1169 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDMDIA)) 1170 .addFrameIndex(FI)) 1171 .addMemOperand(MMO); 1172 MIB = AddDReg(MIB, DestReg, ARM::dsub_0, RegState::DefineNoRead, TRI); 1173 MIB = AddDReg(MIB, DestReg, ARM::dsub_1, RegState::DefineNoRead, TRI); 1174 MIB = AddDReg(MIB, DestReg, ARM::dsub_2, RegState::DefineNoRead, TRI); 1175 MIB = AddDReg(MIB, DestReg, ARM::dsub_3, RegState::DefineNoRead, TRI); 1176 if (TargetRegisterInfo::isPhysicalRegister(DestReg)) 1177 MIB.addReg(DestReg, RegState::ImplicitDefine); 1178 } 1179 } else 1180 llvm_unreachable("Unknown reg class!"); 1181 break; 1182 case 64: 1183 if (ARM::QQQQPRRegClass.hasSubClassEq(RC)) { 1184 MachineInstrBuilder MIB = 1185 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDMDIA)) 1186 .addFrameIndex(FI)) 1187 .addMemOperand(MMO); 1188 MIB = AddDReg(MIB, DestReg, ARM::dsub_0, RegState::DefineNoRead, TRI); 1189 MIB = AddDReg(MIB, DestReg, ARM::dsub_1, RegState::DefineNoRead, TRI); 1190 MIB = AddDReg(MIB, DestReg, ARM::dsub_2, RegState::DefineNoRead, TRI); 1191 MIB = AddDReg(MIB, DestReg, ARM::dsub_3, RegState::DefineNoRead, TRI); 1192 MIB = AddDReg(MIB, DestReg, ARM::dsub_4, RegState::DefineNoRead, TRI); 1193 MIB = AddDReg(MIB, DestReg, ARM::dsub_5, RegState::DefineNoRead, TRI); 1194 MIB = AddDReg(MIB, DestReg, ARM::dsub_6, RegState::DefineNoRead, TRI); 1195 MIB = AddDReg(MIB, DestReg, ARM::dsub_7, RegState::DefineNoRead, TRI); 1196 if (TargetRegisterInfo::isPhysicalRegister(DestReg)) 1197 MIB.addReg(DestReg, RegState::ImplicitDefine); 1198 } else 1199 llvm_unreachable("Unknown reg class!"); 1200 break; 1201 default: 1202 llvm_unreachable("Unknown regclass!"); 1203 } 1204 } 1205 1206 unsigned 1207 ARMBaseInstrInfo::isLoadFromStackSlot(const MachineInstr *MI, 1208 int &FrameIndex) const { 1209 switch (MI->getOpcode()) { 1210 default: break; 1211 case ARM::LDRrs: 1212 case ARM::t2LDRs: // FIXME: don't use t2LDRs to access frame. 1213 if (MI->getOperand(1).isFI() && 1214 MI->getOperand(2).isReg() && 1215 MI->getOperand(3).isImm() && 1216 MI->getOperand(2).getReg() == 0 && 1217 MI->getOperand(3).getImm() == 0) { 1218 FrameIndex = MI->getOperand(1).getIndex(); 1219 return MI->getOperand(0).getReg(); 1220 } 1221 break; 1222 case ARM::LDRi12: 1223 case ARM::t2LDRi12: 1224 case ARM::tLDRspi: 1225 case ARM::VLDRD: 1226 case ARM::VLDRS: 1227 if (MI->getOperand(1).isFI() && 1228 MI->getOperand(2).isImm() && 1229 MI->getOperand(2).getImm() == 0) { 1230 FrameIndex = MI->getOperand(1).getIndex(); 1231 return MI->getOperand(0).getReg(); 1232 } 1233 break; 1234 case ARM::VLD1q64: 1235 case ARM::VLD1d64TPseudo: 1236 case ARM::VLD1d64QPseudo: 1237 if (MI->getOperand(1).isFI() && 1238 MI->getOperand(0).getSubReg() == 0) { 1239 FrameIndex = MI->getOperand(1).getIndex(); 1240 return MI->getOperand(0).getReg(); 1241 } 1242 break; 1243 case ARM::VLDMQIA: 1244 if (MI->getOperand(1).isFI() && 1245 MI->getOperand(0).getSubReg() == 0) { 1246 FrameIndex = MI->getOperand(1).getIndex(); 1247 return MI->getOperand(0).getReg(); 1248 } 1249 break; 1250 } 1251 1252 return 0; 1253 } 1254 1255 unsigned ARMBaseInstrInfo::isLoadFromStackSlotPostFE(const MachineInstr *MI, 1256 int &FrameIndex) const { 1257 const MachineMemOperand *Dummy; 1258 return MI->mayLoad() && hasLoadFromStackSlot(MI, Dummy, FrameIndex); 1259 } 1260 1261 bool 1262 ARMBaseInstrInfo::expandPostRAPseudo(MachineBasicBlock::iterator MI) const { 1263 MachineFunction &MF = *MI->getParent()->getParent(); 1264 Reloc::Model RM = MF.getTarget().getRelocationModel(); 1265 1266 if (MI->getOpcode() == TargetOpcode::LOAD_STACK_GUARD) { 1267 assert(getSubtarget().getTargetTriple().getObjectFormat() == 1268 Triple::MachO && 1269 "LOAD_STACK_GUARD currently supported only for MachO."); 1270 expandLoadStackGuard(MI, RM); 1271 MI->getParent()->erase(MI); 1272 return true; 1273 } 1274 1275 // This hook gets to expand COPY instructions before they become 1276 // copyPhysReg() calls. Look for VMOVS instructions that can legally be 1277 // widened to VMOVD. We prefer the VMOVD when possible because it may be 1278 // changed into a VORR that can go down the NEON pipeline. 1279 if (!WidenVMOVS || !MI->isCopy() || Subtarget.isCortexA15() || 1280 Subtarget.isFPOnlySP()) 1281 return false; 1282 1283 // Look for a copy between even S-registers. That is where we keep floats 1284 // when using NEON v2f32 instructions for f32 arithmetic. 1285 unsigned DstRegS = MI->getOperand(0).getReg(); 1286 unsigned SrcRegS = MI->getOperand(1).getReg(); 1287 if (!ARM::SPRRegClass.contains(DstRegS, SrcRegS)) 1288 return false; 1289 1290 const TargetRegisterInfo *TRI = &getRegisterInfo(); 1291 unsigned DstRegD = TRI->getMatchingSuperReg(DstRegS, ARM::ssub_0, 1292 &ARM::DPRRegClass); 1293 unsigned SrcRegD = TRI->getMatchingSuperReg(SrcRegS, ARM::ssub_0, 1294 &ARM::DPRRegClass); 1295 if (!DstRegD || !SrcRegD) 1296 return false; 1297 1298 // We want to widen this into a DstRegD = VMOVD SrcRegD copy. This is only 1299 // legal if the COPY already defines the full DstRegD, and it isn't a 1300 // sub-register insertion. 1301 if (!MI->definesRegister(DstRegD, TRI) || MI->readsRegister(DstRegD, TRI)) 1302 return false; 1303 1304 // A dead copy shouldn't show up here, but reject it just in case. 1305 if (MI->getOperand(0).isDead()) 1306 return false; 1307 1308 // All clear, widen the COPY. 1309 DEBUG(dbgs() << "widening: " << *MI); 1310 MachineInstrBuilder MIB(*MI->getParent()->getParent(), MI); 1311 1312 // Get rid of the old <imp-def> of DstRegD. Leave it if it defines a Q-reg 1313 // or some other super-register. 1314 int ImpDefIdx = MI->findRegisterDefOperandIdx(DstRegD); 1315 if (ImpDefIdx != -1) 1316 MI->RemoveOperand(ImpDefIdx); 1317 1318 // Change the opcode and operands. 1319 MI->setDesc(get(ARM::VMOVD)); 1320 MI->getOperand(0).setReg(DstRegD); 1321 MI->getOperand(1).setReg(SrcRegD); 1322 AddDefaultPred(MIB); 1323 1324 // We are now reading SrcRegD instead of SrcRegS. This may upset the 1325 // register scavenger and machine verifier, so we need to indicate that we 1326 // are reading an undefined value from SrcRegD, but a proper value from 1327 // SrcRegS. 1328 MI->getOperand(1).setIsUndef(); 1329 MIB.addReg(SrcRegS, RegState::Implicit); 1330 1331 // SrcRegD may actually contain an unrelated value in the ssub_1 1332 // sub-register. Don't kill it. Only kill the ssub_0 sub-register. 1333 if (MI->getOperand(1).isKill()) { 1334 MI->getOperand(1).setIsKill(false); 1335 MI->addRegisterKilled(SrcRegS, TRI, true); 1336 } 1337 1338 DEBUG(dbgs() << "replaced by: " << *MI); 1339 return true; 1340 } 1341 1342 /// Create a copy of a const pool value. Update CPI to the new index and return 1343 /// the label UID. 1344 static unsigned duplicateCPV(MachineFunction &MF, unsigned &CPI) { 1345 MachineConstantPool *MCP = MF.getConstantPool(); 1346 ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>(); 1347 1348 const MachineConstantPoolEntry &MCPE = MCP->getConstants()[CPI]; 1349 assert(MCPE.isMachineConstantPoolEntry() && 1350 "Expecting a machine constantpool entry!"); 1351 ARMConstantPoolValue *ACPV = 1352 static_cast<ARMConstantPoolValue*>(MCPE.Val.MachineCPVal); 1353 1354 unsigned PCLabelId = AFI->createPICLabelUId(); 1355 ARMConstantPoolValue *NewCPV = nullptr; 1356 1357 // FIXME: The below assumes PIC relocation model and that the function 1358 // is Thumb mode (t1 or t2). PCAdjustment would be 8 for ARM mode PIC, and 1359 // zero for non-PIC in ARM or Thumb. The callers are all of thumb LDR 1360 // instructions, so that's probably OK, but is PIC always correct when 1361 // we get here? 1362 if (ACPV->isGlobalValue()) 1363 NewCPV = ARMConstantPoolConstant:: 1364 Create(cast<ARMConstantPoolConstant>(ACPV)->getGV(), PCLabelId, 1365 ARMCP::CPValue, 4); 1366 else if (ACPV->isExtSymbol()) 1367 NewCPV = ARMConstantPoolSymbol:: 1368 Create(MF.getFunction()->getContext(), 1369 cast<ARMConstantPoolSymbol>(ACPV)->getSymbol(), PCLabelId, 4); 1370 else if (ACPV->isBlockAddress()) 1371 NewCPV = ARMConstantPoolConstant:: 1372 Create(cast<ARMConstantPoolConstant>(ACPV)->getBlockAddress(), PCLabelId, 1373 ARMCP::CPBlockAddress, 4); 1374 else if (ACPV->isLSDA()) 1375 NewCPV = ARMConstantPoolConstant::Create(MF.getFunction(), PCLabelId, 1376 ARMCP::CPLSDA, 4); 1377 else if (ACPV->isMachineBasicBlock()) 1378 NewCPV = ARMConstantPoolMBB:: 1379 Create(MF.getFunction()->getContext(), 1380 cast<ARMConstantPoolMBB>(ACPV)->getMBB(), PCLabelId, 4); 1381 else 1382 llvm_unreachable("Unexpected ARM constantpool value type!!"); 1383 CPI = MCP->getConstantPoolIndex(NewCPV, MCPE.getAlignment()); 1384 return PCLabelId; 1385 } 1386 1387 void ARMBaseInstrInfo:: 1388 reMaterialize(MachineBasicBlock &MBB, 1389 MachineBasicBlock::iterator I, 1390 unsigned DestReg, unsigned SubIdx, 1391 const MachineInstr *Orig, 1392 const TargetRegisterInfo &TRI) const { 1393 unsigned Opcode = Orig->getOpcode(); 1394 switch (Opcode) { 1395 default: { 1396 MachineInstr *MI = MBB.getParent()->CloneMachineInstr(Orig); 1397 MI->substituteRegister(Orig->getOperand(0).getReg(), DestReg, SubIdx, TRI); 1398 MBB.insert(I, MI); 1399 break; 1400 } 1401 case ARM::tLDRpci_pic: 1402 case ARM::t2LDRpci_pic: { 1403 MachineFunction &MF = *MBB.getParent(); 1404 unsigned CPI = Orig->getOperand(1).getIndex(); 1405 unsigned PCLabelId = duplicateCPV(MF, CPI); 1406 MachineInstrBuilder MIB = BuildMI(MBB, I, Orig->getDebugLoc(), get(Opcode), 1407 DestReg) 1408 .addConstantPoolIndex(CPI).addImm(PCLabelId); 1409 MIB->setMemRefs(Orig->memoperands_begin(), Orig->memoperands_end()); 1410 break; 1411 } 1412 } 1413 } 1414 1415 MachineInstr * 1416 ARMBaseInstrInfo::duplicate(MachineInstr *Orig, MachineFunction &MF) const { 1417 MachineInstr *MI = TargetInstrInfo::duplicate(Orig, MF); 1418 switch(Orig->getOpcode()) { 1419 case ARM::tLDRpci_pic: 1420 case ARM::t2LDRpci_pic: { 1421 unsigned CPI = Orig->getOperand(1).getIndex(); 1422 unsigned PCLabelId = duplicateCPV(MF, CPI); 1423 Orig->getOperand(1).setIndex(CPI); 1424 Orig->getOperand(2).setImm(PCLabelId); 1425 break; 1426 } 1427 } 1428 return MI; 1429 } 1430 1431 bool ARMBaseInstrInfo::produceSameValue(const MachineInstr *MI0, 1432 const MachineInstr *MI1, 1433 const MachineRegisterInfo *MRI) const { 1434 int Opcode = MI0->getOpcode(); 1435 if (Opcode == ARM::t2LDRpci || 1436 Opcode == ARM::t2LDRpci_pic || 1437 Opcode == ARM::tLDRpci || 1438 Opcode == ARM::tLDRpci_pic || 1439 Opcode == ARM::LDRLIT_ga_pcrel || 1440 Opcode == ARM::LDRLIT_ga_pcrel_ldr || 1441 Opcode == ARM::tLDRLIT_ga_pcrel || 1442 Opcode == ARM::MOV_ga_pcrel || 1443 Opcode == ARM::MOV_ga_pcrel_ldr || 1444 Opcode == ARM::t2MOV_ga_pcrel) { 1445 if (MI1->getOpcode() != Opcode) 1446 return false; 1447 if (MI0->getNumOperands() != MI1->getNumOperands()) 1448 return false; 1449 1450 const MachineOperand &MO0 = MI0->getOperand(1); 1451 const MachineOperand &MO1 = MI1->getOperand(1); 1452 if (MO0.getOffset() != MO1.getOffset()) 1453 return false; 1454 1455 if (Opcode == ARM::LDRLIT_ga_pcrel || 1456 Opcode == ARM::LDRLIT_ga_pcrel_ldr || 1457 Opcode == ARM::tLDRLIT_ga_pcrel || 1458 Opcode == ARM::MOV_ga_pcrel || 1459 Opcode == ARM::MOV_ga_pcrel_ldr || 1460 Opcode == ARM::t2MOV_ga_pcrel) 1461 // Ignore the PC labels. 1462 return MO0.getGlobal() == MO1.getGlobal(); 1463 1464 const MachineFunction *MF = MI0->getParent()->getParent(); 1465 const MachineConstantPool *MCP = MF->getConstantPool(); 1466 int CPI0 = MO0.getIndex(); 1467 int CPI1 = MO1.getIndex(); 1468 const MachineConstantPoolEntry &MCPE0 = MCP->getConstants()[CPI0]; 1469 const MachineConstantPoolEntry &MCPE1 = MCP->getConstants()[CPI1]; 1470 bool isARMCP0 = MCPE0.isMachineConstantPoolEntry(); 1471 bool isARMCP1 = MCPE1.isMachineConstantPoolEntry(); 1472 if (isARMCP0 && isARMCP1) { 1473 ARMConstantPoolValue *ACPV0 = 1474 static_cast<ARMConstantPoolValue*>(MCPE0.Val.MachineCPVal); 1475 ARMConstantPoolValue *ACPV1 = 1476 static_cast<ARMConstantPoolValue*>(MCPE1.Val.MachineCPVal); 1477 return ACPV0->hasSameValue(ACPV1); 1478 } else if (!isARMCP0 && !isARMCP1) { 1479 return MCPE0.Val.ConstVal == MCPE1.Val.ConstVal; 1480 } 1481 return false; 1482 } else if (Opcode == ARM::PICLDR) { 1483 if (MI1->getOpcode() != Opcode) 1484 return false; 1485 if (MI0->getNumOperands() != MI1->getNumOperands()) 1486 return false; 1487 1488 unsigned Addr0 = MI0->getOperand(1).getReg(); 1489 unsigned Addr1 = MI1->getOperand(1).getReg(); 1490 if (Addr0 != Addr1) { 1491 if (!MRI || 1492 !TargetRegisterInfo::isVirtualRegister(Addr0) || 1493 !TargetRegisterInfo::isVirtualRegister(Addr1)) 1494 return false; 1495 1496 // This assumes SSA form. 1497 MachineInstr *Def0 = MRI->getVRegDef(Addr0); 1498 MachineInstr *Def1 = MRI->getVRegDef(Addr1); 1499 // Check if the loaded value, e.g. a constantpool of a global address, are 1500 // the same. 1501 if (!produceSameValue(Def0, Def1, MRI)) 1502 return false; 1503 } 1504 1505 for (unsigned i = 3, e = MI0->getNumOperands(); i != e; ++i) { 1506 // %vreg12<def> = PICLDR %vreg11, 0, pred:14, pred:%noreg 1507 const MachineOperand &MO0 = MI0->getOperand(i); 1508 const MachineOperand &MO1 = MI1->getOperand(i); 1509 if (!MO0.isIdenticalTo(MO1)) 1510 return false; 1511 } 1512 return true; 1513 } 1514 1515 return MI0->isIdenticalTo(MI1, MachineInstr::IgnoreVRegDefs); 1516 } 1517 1518 /// areLoadsFromSameBasePtr - This is used by the pre-regalloc scheduler to 1519 /// determine if two loads are loading from the same base address. It should 1520 /// only return true if the base pointers are the same and the only differences 1521 /// between the two addresses is the offset. It also returns the offsets by 1522 /// reference. 1523 /// 1524 /// FIXME: remove this in favor of the MachineInstr interface once pre-RA-sched 1525 /// is permanently disabled. 1526 bool ARMBaseInstrInfo::areLoadsFromSameBasePtr(SDNode *Load1, SDNode *Load2, 1527 int64_t &Offset1, 1528 int64_t &Offset2) const { 1529 // Don't worry about Thumb: just ARM and Thumb2. 1530 if (Subtarget.isThumb1Only()) return false; 1531 1532 if (!Load1->isMachineOpcode() || !Load2->isMachineOpcode()) 1533 return false; 1534 1535 switch (Load1->getMachineOpcode()) { 1536 default: 1537 return false; 1538 case ARM::LDRi12: 1539 case ARM::LDRBi12: 1540 case ARM::LDRD: 1541 case ARM::LDRH: 1542 case ARM::LDRSB: 1543 case ARM::LDRSH: 1544 case ARM::VLDRD: 1545 case ARM::VLDRS: 1546 case ARM::t2LDRi8: 1547 case ARM::t2LDRBi8: 1548 case ARM::t2LDRDi8: 1549 case ARM::t2LDRSHi8: 1550 case ARM::t2LDRi12: 1551 case ARM::t2LDRBi12: 1552 case ARM::t2LDRSHi12: 1553 break; 1554 } 1555 1556 switch (Load2->getMachineOpcode()) { 1557 default: 1558 return false; 1559 case ARM::LDRi12: 1560 case ARM::LDRBi12: 1561 case ARM::LDRD: 1562 case ARM::LDRH: 1563 case ARM::LDRSB: 1564 case ARM::LDRSH: 1565 case ARM::VLDRD: 1566 case ARM::VLDRS: 1567 case ARM::t2LDRi8: 1568 case ARM::t2LDRBi8: 1569 case ARM::t2LDRSHi8: 1570 case ARM::t2LDRi12: 1571 case ARM::t2LDRBi12: 1572 case ARM::t2LDRSHi12: 1573 break; 1574 } 1575 1576 // Check if base addresses and chain operands match. 1577 if (Load1->getOperand(0) != Load2->getOperand(0) || 1578 Load1->getOperand(4) != Load2->getOperand(4)) 1579 return false; 1580 1581 // Index should be Reg0. 1582 if (Load1->getOperand(3) != Load2->getOperand(3)) 1583 return false; 1584 1585 // Determine the offsets. 1586 if (isa<ConstantSDNode>(Load1->getOperand(1)) && 1587 isa<ConstantSDNode>(Load2->getOperand(1))) { 1588 Offset1 = cast<ConstantSDNode>(Load1->getOperand(1))->getSExtValue(); 1589 Offset2 = cast<ConstantSDNode>(Load2->getOperand(1))->getSExtValue(); 1590 return true; 1591 } 1592 1593 return false; 1594 } 1595 1596 /// shouldScheduleLoadsNear - This is a used by the pre-regalloc scheduler to 1597 /// determine (in conjunction with areLoadsFromSameBasePtr) if two loads should 1598 /// be scheduled togther. On some targets if two loads are loading from 1599 /// addresses in the same cache line, it's better if they are scheduled 1600 /// together. This function takes two integers that represent the load offsets 1601 /// from the common base address. It returns true if it decides it's desirable 1602 /// to schedule the two loads together. "NumLoads" is the number of loads that 1603 /// have already been scheduled after Load1. 1604 /// 1605 /// FIXME: remove this in favor of the MachineInstr interface once pre-RA-sched 1606 /// is permanently disabled. 1607 bool ARMBaseInstrInfo::shouldScheduleLoadsNear(SDNode *Load1, SDNode *Load2, 1608 int64_t Offset1, int64_t Offset2, 1609 unsigned NumLoads) const { 1610 // Don't worry about Thumb: just ARM and Thumb2. 1611 if (Subtarget.isThumb1Only()) return false; 1612 1613 assert(Offset2 > Offset1); 1614 1615 if ((Offset2 - Offset1) / 8 > 64) 1616 return false; 1617 1618 // Check if the machine opcodes are different. If they are different 1619 // then we consider them to not be of the same base address, 1620 // EXCEPT in the case of Thumb2 byte loads where one is LDRBi8 and the other LDRBi12. 1621 // In this case, they are considered to be the same because they are different 1622 // encoding forms of the same basic instruction. 1623 if ((Load1->getMachineOpcode() != Load2->getMachineOpcode()) && 1624 !((Load1->getMachineOpcode() == ARM::t2LDRBi8 && 1625 Load2->getMachineOpcode() == ARM::t2LDRBi12) || 1626 (Load1->getMachineOpcode() == ARM::t2LDRBi12 && 1627 Load2->getMachineOpcode() == ARM::t2LDRBi8))) 1628 return false; // FIXME: overly conservative? 1629 1630 // Four loads in a row should be sufficient. 1631 if (NumLoads >= 3) 1632 return false; 1633 1634 return true; 1635 } 1636 1637 bool ARMBaseInstrInfo::isSchedulingBoundary(const MachineInstr *MI, 1638 const MachineBasicBlock *MBB, 1639 const MachineFunction &MF) const { 1640 // Debug info is never a scheduling boundary. It's necessary to be explicit 1641 // due to the special treatment of IT instructions below, otherwise a 1642 // dbg_value followed by an IT will result in the IT instruction being 1643 // considered a scheduling hazard, which is wrong. It should be the actual 1644 // instruction preceding the dbg_value instruction(s), just like it is 1645 // when debug info is not present. 1646 if (MI->isDebugValue()) 1647 return false; 1648 1649 // Terminators and labels can't be scheduled around. 1650 if (MI->isTerminator() || MI->isPosition()) 1651 return true; 1652 1653 // Treat the start of the IT block as a scheduling boundary, but schedule 1654 // t2IT along with all instructions following it. 1655 // FIXME: This is a big hammer. But the alternative is to add all potential 1656 // true and anti dependencies to IT block instructions as implicit operands 1657 // to the t2IT instruction. The added compile time and complexity does not 1658 // seem worth it. 1659 MachineBasicBlock::const_iterator I = MI; 1660 // Make sure to skip any dbg_value instructions 1661 while (++I != MBB->end() && I->isDebugValue()) 1662 ; 1663 if (I != MBB->end() && I->getOpcode() == ARM::t2IT) 1664 return true; 1665 1666 // Don't attempt to schedule around any instruction that defines 1667 // a stack-oriented pointer, as it's unlikely to be profitable. This 1668 // saves compile time, because it doesn't require every single 1669 // stack slot reference to depend on the instruction that does the 1670 // modification. 1671 // Calls don't actually change the stack pointer, even if they have imp-defs. 1672 // No ARM calling conventions change the stack pointer. (X86 calling 1673 // conventions sometimes do). 1674 if (!MI->isCall() && MI->definesRegister(ARM::SP)) 1675 return true; 1676 1677 return false; 1678 } 1679 1680 bool ARMBaseInstrInfo:: 1681 isProfitableToIfCvt(MachineBasicBlock &MBB, 1682 unsigned NumCycles, unsigned ExtraPredCycles, 1683 const BranchProbability &Probability) const { 1684 if (!NumCycles) 1685 return false; 1686 1687 // Attempt to estimate the relative costs of predication versus branching. 1688 unsigned UnpredCost = Probability.getNumerator() * NumCycles; 1689 UnpredCost /= Probability.getDenominator(); 1690 UnpredCost += 1; // The branch itself 1691 UnpredCost += Subtarget.getMispredictionPenalty() / 10; 1692 1693 return (NumCycles + ExtraPredCycles) <= UnpredCost; 1694 } 1695 1696 bool ARMBaseInstrInfo:: 1697 isProfitableToIfCvt(MachineBasicBlock &TMBB, 1698 unsigned TCycles, unsigned TExtra, 1699 MachineBasicBlock &FMBB, 1700 unsigned FCycles, unsigned FExtra, 1701 const BranchProbability &Probability) const { 1702 if (!TCycles || !FCycles) 1703 return false; 1704 1705 // Attempt to estimate the relative costs of predication versus branching. 1706 unsigned TUnpredCost = Probability.getNumerator() * TCycles; 1707 TUnpredCost /= Probability.getDenominator(); 1708 1709 uint32_t Comp = Probability.getDenominator() - Probability.getNumerator(); 1710 unsigned FUnpredCost = Comp * FCycles; 1711 FUnpredCost /= Probability.getDenominator(); 1712 1713 unsigned UnpredCost = TUnpredCost + FUnpredCost; 1714 UnpredCost += 1; // The branch itself 1715 UnpredCost += Subtarget.getMispredictionPenalty() / 10; 1716 1717 return (TCycles + FCycles + TExtra + FExtra) <= UnpredCost; 1718 } 1719 1720 bool 1721 ARMBaseInstrInfo::isProfitableToUnpredicate(MachineBasicBlock &TMBB, 1722 MachineBasicBlock &FMBB) const { 1723 // Reduce false anti-dependencies to let Swift's out-of-order execution 1724 // engine do its thing. 1725 return Subtarget.isSwift(); 1726 } 1727 1728 /// getInstrPredicate - If instruction is predicated, returns its predicate 1729 /// condition, otherwise returns AL. It also returns the condition code 1730 /// register by reference. 1731 ARMCC::CondCodes 1732 llvm::getInstrPredicate(const MachineInstr *MI, unsigned &PredReg) { 1733 int PIdx = MI->findFirstPredOperandIdx(); 1734 if (PIdx == -1) { 1735 PredReg = 0; 1736 return ARMCC::AL; 1737 } 1738 1739 PredReg = MI->getOperand(PIdx+1).getReg(); 1740 return (ARMCC::CondCodes)MI->getOperand(PIdx).getImm(); 1741 } 1742 1743 1744 int llvm::getMatchingCondBranchOpcode(int Opc) { 1745 if (Opc == ARM::B) 1746 return ARM::Bcc; 1747 if (Opc == ARM::tB) 1748 return ARM::tBcc; 1749 if (Opc == ARM::t2B) 1750 return ARM::t2Bcc; 1751 1752 llvm_unreachable("Unknown unconditional branch opcode!"); 1753 } 1754 1755 /// commuteInstruction - Handle commutable instructions. 1756 MachineInstr * 1757 ARMBaseInstrInfo::commuteInstruction(MachineInstr *MI, bool NewMI) const { 1758 switch (MI->getOpcode()) { 1759 case ARM::MOVCCr: 1760 case ARM::t2MOVCCr: { 1761 // MOVCC can be commuted by inverting the condition. 1762 unsigned PredReg = 0; 1763 ARMCC::CondCodes CC = getInstrPredicate(MI, PredReg); 1764 // MOVCC AL can't be inverted. Shouldn't happen. 1765 if (CC == ARMCC::AL || PredReg != ARM::CPSR) 1766 return nullptr; 1767 MI = TargetInstrInfo::commuteInstruction(MI, NewMI); 1768 if (!MI) 1769 return nullptr; 1770 // After swapping the MOVCC operands, also invert the condition. 1771 MI->getOperand(MI->findFirstPredOperandIdx()) 1772 .setImm(ARMCC::getOppositeCondition(CC)); 1773 return MI; 1774 } 1775 } 1776 return TargetInstrInfo::commuteInstruction(MI, NewMI); 1777 } 1778 1779 /// Identify instructions that can be folded into a MOVCC instruction, and 1780 /// return the defining instruction. 1781 static MachineInstr *canFoldIntoMOVCC(unsigned Reg, 1782 const MachineRegisterInfo &MRI, 1783 const TargetInstrInfo *TII) { 1784 if (!TargetRegisterInfo::isVirtualRegister(Reg)) 1785 return nullptr; 1786 if (!MRI.hasOneNonDBGUse(Reg)) 1787 return nullptr; 1788 MachineInstr *MI = MRI.getVRegDef(Reg); 1789 if (!MI) 1790 return nullptr; 1791 // MI is folded into the MOVCC by predicating it. 1792 if (!MI->isPredicable()) 1793 return nullptr; 1794 // Check if MI has any non-dead defs or physreg uses. This also detects 1795 // predicated instructions which will be reading CPSR. 1796 for (unsigned i = 1, e = MI->getNumOperands(); i != e; ++i) { 1797 const MachineOperand &MO = MI->getOperand(i); 1798 // Reject frame index operands, PEI can't handle the predicated pseudos. 1799 if (MO.isFI() || MO.isCPI() || MO.isJTI()) 1800 return nullptr; 1801 if (!MO.isReg()) 1802 continue; 1803 // MI can't have any tied operands, that would conflict with predication. 1804 if (MO.isTied()) 1805 return nullptr; 1806 if (TargetRegisterInfo::isPhysicalRegister(MO.getReg())) 1807 return nullptr; 1808 if (MO.isDef() && !MO.isDead()) 1809 return nullptr; 1810 } 1811 bool DontMoveAcrossStores = true; 1812 if (!MI->isSafeToMove(TII, /* AliasAnalysis = */ nullptr, 1813 DontMoveAcrossStores)) 1814 return nullptr; 1815 return MI; 1816 } 1817 1818 bool ARMBaseInstrInfo::analyzeSelect(const MachineInstr *MI, 1819 SmallVectorImpl<MachineOperand> &Cond, 1820 unsigned &TrueOp, unsigned &FalseOp, 1821 bool &Optimizable) const { 1822 assert((MI->getOpcode() == ARM::MOVCCr || MI->getOpcode() == ARM::t2MOVCCr) && 1823 "Unknown select instruction"); 1824 // MOVCC operands: 1825 // 0: Def. 1826 // 1: True use. 1827 // 2: False use. 1828 // 3: Condition code. 1829 // 4: CPSR use. 1830 TrueOp = 1; 1831 FalseOp = 2; 1832 Cond.push_back(MI->getOperand(3)); 1833 Cond.push_back(MI->getOperand(4)); 1834 // We can always fold a def. 1835 Optimizable = true; 1836 return false; 1837 } 1838 1839 MachineInstr * 1840 ARMBaseInstrInfo::optimizeSelect(MachineInstr *MI, 1841 SmallPtrSetImpl<MachineInstr *> &SeenMIs, 1842 bool PreferFalse) const { 1843 assert((MI->getOpcode() == ARM::MOVCCr || MI->getOpcode() == ARM::t2MOVCCr) && 1844 "Unknown select instruction"); 1845 MachineRegisterInfo &MRI = MI->getParent()->getParent()->getRegInfo(); 1846 MachineInstr *DefMI = canFoldIntoMOVCC(MI->getOperand(2).getReg(), MRI, this); 1847 bool Invert = !DefMI; 1848 if (!DefMI) 1849 DefMI = canFoldIntoMOVCC(MI->getOperand(1).getReg(), MRI, this); 1850 if (!DefMI) 1851 return nullptr; 1852 1853 // Find new register class to use. 1854 MachineOperand FalseReg = MI->getOperand(Invert ? 2 : 1); 1855 unsigned DestReg = MI->getOperand(0).getReg(); 1856 const TargetRegisterClass *PreviousClass = MRI.getRegClass(FalseReg.getReg()); 1857 if (!MRI.constrainRegClass(DestReg, PreviousClass)) 1858 return nullptr; 1859 1860 // Create a new predicated version of DefMI. 1861 // Rfalse is the first use. 1862 MachineInstrBuilder NewMI = BuildMI(*MI->getParent(), MI, MI->getDebugLoc(), 1863 DefMI->getDesc(), DestReg); 1864 1865 // Copy all the DefMI operands, excluding its (null) predicate. 1866 const MCInstrDesc &DefDesc = DefMI->getDesc(); 1867 for (unsigned i = 1, e = DefDesc.getNumOperands(); 1868 i != e && !DefDesc.OpInfo[i].isPredicate(); ++i) 1869 NewMI.addOperand(DefMI->getOperand(i)); 1870 1871 unsigned CondCode = MI->getOperand(3).getImm(); 1872 if (Invert) 1873 NewMI.addImm(ARMCC::getOppositeCondition(ARMCC::CondCodes(CondCode))); 1874 else 1875 NewMI.addImm(CondCode); 1876 NewMI.addOperand(MI->getOperand(4)); 1877 1878 // DefMI is not the -S version that sets CPSR, so add an optional %noreg. 1879 if (NewMI->hasOptionalDef()) 1880 AddDefaultCC(NewMI); 1881 1882 // The output register value when the predicate is false is an implicit 1883 // register operand tied to the first def. 1884 // The tie makes the register allocator ensure the FalseReg is allocated the 1885 // same register as operand 0. 1886 FalseReg.setImplicit(); 1887 NewMI.addOperand(FalseReg); 1888 NewMI->tieOperands(0, NewMI->getNumOperands() - 1); 1889 1890 // Update SeenMIs set: register newly created MI and erase removed DefMI. 1891 SeenMIs.insert(NewMI); 1892 SeenMIs.erase(DefMI); 1893 1894 // The caller will erase MI, but not DefMI. 1895 DefMI->eraseFromParent(); 1896 return NewMI; 1897 } 1898 1899 /// Map pseudo instructions that imply an 'S' bit onto real opcodes. Whether the 1900 /// instruction is encoded with an 'S' bit is determined by the optional CPSR 1901 /// def operand. 1902 /// 1903 /// This will go away once we can teach tblgen how to set the optional CPSR def 1904 /// operand itself. 1905 struct AddSubFlagsOpcodePair { 1906 uint16_t PseudoOpc; 1907 uint16_t MachineOpc; 1908 }; 1909 1910 static const AddSubFlagsOpcodePair AddSubFlagsOpcodeMap[] = { 1911 {ARM::ADDSri, ARM::ADDri}, 1912 {ARM::ADDSrr, ARM::ADDrr}, 1913 {ARM::ADDSrsi, ARM::ADDrsi}, 1914 {ARM::ADDSrsr, ARM::ADDrsr}, 1915 1916 {ARM::SUBSri, ARM::SUBri}, 1917 {ARM::SUBSrr, ARM::SUBrr}, 1918 {ARM::SUBSrsi, ARM::SUBrsi}, 1919 {ARM::SUBSrsr, ARM::SUBrsr}, 1920 1921 {ARM::RSBSri, ARM::RSBri}, 1922 {ARM::RSBSrsi, ARM::RSBrsi}, 1923 {ARM::RSBSrsr, ARM::RSBrsr}, 1924 1925 {ARM::t2ADDSri, ARM::t2ADDri}, 1926 {ARM::t2ADDSrr, ARM::t2ADDrr}, 1927 {ARM::t2ADDSrs, ARM::t2ADDrs}, 1928 1929 {ARM::t2SUBSri, ARM::t2SUBri}, 1930 {ARM::t2SUBSrr, ARM::t2SUBrr}, 1931 {ARM::t2SUBSrs, ARM::t2SUBrs}, 1932 1933 {ARM::t2RSBSri, ARM::t2RSBri}, 1934 {ARM::t2RSBSrs, ARM::t2RSBrs}, 1935 }; 1936 1937 unsigned llvm::convertAddSubFlagsOpcode(unsigned OldOpc) { 1938 for (unsigned i = 0, e = array_lengthof(AddSubFlagsOpcodeMap); i != e; ++i) 1939 if (OldOpc == AddSubFlagsOpcodeMap[i].PseudoOpc) 1940 return AddSubFlagsOpcodeMap[i].MachineOpc; 1941 return 0; 1942 } 1943 1944 void llvm::emitARMRegPlusImmediate(MachineBasicBlock &MBB, 1945 MachineBasicBlock::iterator &MBBI, DebugLoc dl, 1946 unsigned DestReg, unsigned BaseReg, int NumBytes, 1947 ARMCC::CondCodes Pred, unsigned PredReg, 1948 const ARMBaseInstrInfo &TII, unsigned MIFlags) { 1949 if (NumBytes == 0 && DestReg != BaseReg) { 1950 BuildMI(MBB, MBBI, dl, TII.get(ARM::MOVr), DestReg) 1951 .addReg(BaseReg, RegState::Kill) 1952 .addImm((unsigned)Pred).addReg(PredReg).addReg(0) 1953 .setMIFlags(MIFlags); 1954 return; 1955 } 1956 1957 bool isSub = NumBytes < 0; 1958 if (isSub) NumBytes = -NumBytes; 1959 1960 while (NumBytes) { 1961 unsigned RotAmt = ARM_AM::getSOImmValRotate(NumBytes); 1962 unsigned ThisVal = NumBytes & ARM_AM::rotr32(0xFF, RotAmt); 1963 assert(ThisVal && "Didn't extract field correctly"); 1964 1965 // We will handle these bits from offset, clear them. 1966 NumBytes &= ~ThisVal; 1967 1968 assert(ARM_AM::getSOImmVal(ThisVal) != -1 && "Bit extraction didn't work?"); 1969 1970 // Build the new ADD / SUB. 1971 unsigned Opc = isSub ? ARM::SUBri : ARM::ADDri; 1972 BuildMI(MBB, MBBI, dl, TII.get(Opc), DestReg) 1973 .addReg(BaseReg, RegState::Kill).addImm(ThisVal) 1974 .addImm((unsigned)Pred).addReg(PredReg).addReg(0) 1975 .setMIFlags(MIFlags); 1976 BaseReg = DestReg; 1977 } 1978 } 1979 1980 static bool isAnySubRegLive(unsigned Reg, const TargetRegisterInfo *TRI, 1981 MachineInstr *MI) { 1982 for (MCSubRegIterator Subreg(Reg, TRI, /* IncludeSelf */ true); 1983 Subreg.isValid(); ++Subreg) 1984 if (MI->getParent()->computeRegisterLiveness(TRI, *Subreg, MI) != 1985 MachineBasicBlock::LQR_Dead) 1986 return true; 1987 return false; 1988 } 1989 bool llvm::tryFoldSPUpdateIntoPushPop(const ARMSubtarget &Subtarget, 1990 MachineFunction &MF, MachineInstr *MI, 1991 unsigned NumBytes) { 1992 // This optimisation potentially adds lots of load and store 1993 // micro-operations, it's only really a great benefit to code-size. 1994 if (!MF.getFunction()->hasFnAttribute(Attribute::MinSize)) 1995 return false; 1996 1997 // If only one register is pushed/popped, LLVM can use an LDR/STR 1998 // instead. We can't modify those so make sure we're dealing with an 1999 // instruction we understand. 2000 bool IsPop = isPopOpcode(MI->getOpcode()); 2001 bool IsPush = isPushOpcode(MI->getOpcode()); 2002 if (!IsPush && !IsPop) 2003 return false; 2004 2005 bool IsVFPPushPop = MI->getOpcode() == ARM::VSTMDDB_UPD || 2006 MI->getOpcode() == ARM::VLDMDIA_UPD; 2007 bool IsT1PushPop = MI->getOpcode() == ARM::tPUSH || 2008 MI->getOpcode() == ARM::tPOP || 2009 MI->getOpcode() == ARM::tPOP_RET; 2010 2011 assert((IsT1PushPop || (MI->getOperand(0).getReg() == ARM::SP && 2012 MI->getOperand(1).getReg() == ARM::SP)) && 2013 "trying to fold sp update into non-sp-updating push/pop"); 2014 2015 // The VFP push & pop act on D-registers, so we can only fold an adjustment 2016 // by a multiple of 8 bytes in correctly. Similarly rN is 4-bytes. Don't try 2017 // if this is violated. 2018 if (NumBytes % (IsVFPPushPop ? 8 : 4) != 0) 2019 return false; 2020 2021 // ARM and Thumb2 push/pop insts have explicit "sp, sp" operands (+ 2022 // pred) so the list starts at 4. Thumb1 starts after the predicate. 2023 int RegListIdx = IsT1PushPop ? 2 : 4; 2024 2025 // Calculate the space we'll need in terms of registers. 2026 unsigned FirstReg = MI->getOperand(RegListIdx).getReg(); 2027 unsigned RD0Reg, RegsNeeded; 2028 if (IsVFPPushPop) { 2029 RD0Reg = ARM::D0; 2030 RegsNeeded = NumBytes / 8; 2031 } else { 2032 RD0Reg = ARM::R0; 2033 RegsNeeded = NumBytes / 4; 2034 } 2035 2036 // We're going to have to strip all list operands off before 2037 // re-adding them since the order matters, so save the existing ones 2038 // for later. 2039 SmallVector<MachineOperand, 4> RegList; 2040 for (int i = MI->getNumOperands() - 1; i >= RegListIdx; --i) 2041 RegList.push_back(MI->getOperand(i)); 2042 2043 const TargetRegisterInfo *TRI = MF.getRegInfo().getTargetRegisterInfo(); 2044 const MCPhysReg *CSRegs = TRI->getCalleeSavedRegs(&MF); 2045 2046 // Now try to find enough space in the reglist to allocate NumBytes. 2047 for (unsigned CurReg = FirstReg - 1; CurReg >= RD0Reg && RegsNeeded; 2048 --CurReg) { 2049 if (!IsPop) { 2050 // Pushing any register is completely harmless, mark the 2051 // register involved as undef since we don't care about it in 2052 // the slightest. 2053 RegList.push_back(MachineOperand::CreateReg(CurReg, false, false, 2054 false, false, true)); 2055 --RegsNeeded; 2056 continue; 2057 } 2058 2059 // However, we can only pop an extra register if it's not live. For 2060 // registers live within the function we might clobber a return value 2061 // register; the other way a register can be live here is if it's 2062 // callee-saved. 2063 // TODO: Currently, computeRegisterLiveness() does not report "live" if a 2064 // sub reg is live. When computeRegisterLiveness() works for sub reg, it 2065 // can replace isAnySubRegLive(). 2066 if (isCalleeSavedRegister(CurReg, CSRegs) || 2067 isAnySubRegLive(CurReg, TRI, MI)) { 2068 // VFP pops don't allow holes in the register list, so any skip is fatal 2069 // for our transformation. GPR pops do, so we should just keep looking. 2070 if (IsVFPPushPop) 2071 return false; 2072 else 2073 continue; 2074 } 2075 2076 // Mark the unimportant registers as <def,dead> in the POP. 2077 RegList.push_back(MachineOperand::CreateReg(CurReg, true, false, false, 2078 true)); 2079 --RegsNeeded; 2080 } 2081 2082 if (RegsNeeded > 0) 2083 return false; 2084 2085 // Finally we know we can profitably perform the optimisation so go 2086 // ahead: strip all existing registers off and add them back again 2087 // in the right order. 2088 for (int i = MI->getNumOperands() - 1; i >= RegListIdx; --i) 2089 MI->RemoveOperand(i); 2090 2091 // Add the complete list back in. 2092 MachineInstrBuilder MIB(MF, &*MI); 2093 for (int i = RegList.size() - 1; i >= 0; --i) 2094 MIB.addOperand(RegList[i]); 2095 2096 return true; 2097 } 2098 2099 bool llvm::rewriteARMFrameIndex(MachineInstr &MI, unsigned FrameRegIdx, 2100 unsigned FrameReg, int &Offset, 2101 const ARMBaseInstrInfo &TII) { 2102 unsigned Opcode = MI.getOpcode(); 2103 const MCInstrDesc &Desc = MI.getDesc(); 2104 unsigned AddrMode = (Desc.TSFlags & ARMII::AddrModeMask); 2105 bool isSub = false; 2106 2107 // Memory operands in inline assembly always use AddrMode2. 2108 if (Opcode == ARM::INLINEASM) 2109 AddrMode = ARMII::AddrMode2; 2110 2111 if (Opcode == ARM::ADDri) { 2112 Offset += MI.getOperand(FrameRegIdx+1).getImm(); 2113 if (Offset == 0) { 2114 // Turn it into a move. 2115 MI.setDesc(TII.get(ARM::MOVr)); 2116 MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false); 2117 MI.RemoveOperand(FrameRegIdx+1); 2118 Offset = 0; 2119 return true; 2120 } else if (Offset < 0) { 2121 Offset = -Offset; 2122 isSub = true; 2123 MI.setDesc(TII.get(ARM::SUBri)); 2124 } 2125 2126 // Common case: small offset, fits into instruction. 2127 if (ARM_AM::getSOImmVal(Offset) != -1) { 2128 // Replace the FrameIndex with sp / fp 2129 MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false); 2130 MI.getOperand(FrameRegIdx+1).ChangeToImmediate(Offset); 2131 Offset = 0; 2132 return true; 2133 } 2134 2135 // Otherwise, pull as much of the immedidate into this ADDri/SUBri 2136 // as possible. 2137 unsigned RotAmt = ARM_AM::getSOImmValRotate(Offset); 2138 unsigned ThisImmVal = Offset & ARM_AM::rotr32(0xFF, RotAmt); 2139 2140 // We will handle these bits from offset, clear them. 2141 Offset &= ~ThisImmVal; 2142 2143 // Get the properly encoded SOImmVal field. 2144 assert(ARM_AM::getSOImmVal(ThisImmVal) != -1 && 2145 "Bit extraction didn't work?"); 2146 MI.getOperand(FrameRegIdx+1).ChangeToImmediate(ThisImmVal); 2147 } else { 2148 unsigned ImmIdx = 0; 2149 int InstrOffs = 0; 2150 unsigned NumBits = 0; 2151 unsigned Scale = 1; 2152 switch (AddrMode) { 2153 case ARMII::AddrMode_i12: { 2154 ImmIdx = FrameRegIdx + 1; 2155 InstrOffs = MI.getOperand(ImmIdx).getImm(); 2156 NumBits = 12; 2157 break; 2158 } 2159 case ARMII::AddrMode2: { 2160 ImmIdx = FrameRegIdx+2; 2161 InstrOffs = ARM_AM::getAM2Offset(MI.getOperand(ImmIdx).getImm()); 2162 if (ARM_AM::getAM2Op(MI.getOperand(ImmIdx).getImm()) == ARM_AM::sub) 2163 InstrOffs *= -1; 2164 NumBits = 12; 2165 break; 2166 } 2167 case ARMII::AddrMode3: { 2168 ImmIdx = FrameRegIdx+2; 2169 InstrOffs = ARM_AM::getAM3Offset(MI.getOperand(ImmIdx).getImm()); 2170 if (ARM_AM::getAM3Op(MI.getOperand(ImmIdx).getImm()) == ARM_AM::sub) 2171 InstrOffs *= -1; 2172 NumBits = 8; 2173 break; 2174 } 2175 case ARMII::AddrMode4: 2176 case ARMII::AddrMode6: 2177 // Can't fold any offset even if it's zero. 2178 return false; 2179 case ARMII::AddrMode5: { 2180 ImmIdx = FrameRegIdx+1; 2181 InstrOffs = ARM_AM::getAM5Offset(MI.getOperand(ImmIdx).getImm()); 2182 if (ARM_AM::getAM5Op(MI.getOperand(ImmIdx).getImm()) == ARM_AM::sub) 2183 InstrOffs *= -1; 2184 NumBits = 8; 2185 Scale = 4; 2186 break; 2187 } 2188 default: 2189 llvm_unreachable("Unsupported addressing mode!"); 2190 } 2191 2192 Offset += InstrOffs * Scale; 2193 assert((Offset & (Scale-1)) == 0 && "Can't encode this offset!"); 2194 if (Offset < 0) { 2195 Offset = -Offset; 2196 isSub = true; 2197 } 2198 2199 // Attempt to fold address comp. if opcode has offset bits 2200 if (NumBits > 0) { 2201 // Common case: small offset, fits into instruction. 2202 MachineOperand &ImmOp = MI.getOperand(ImmIdx); 2203 int ImmedOffset = Offset / Scale; 2204 unsigned Mask = (1 << NumBits) - 1; 2205 if ((unsigned)Offset <= Mask * Scale) { 2206 // Replace the FrameIndex with sp 2207 MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false); 2208 // FIXME: When addrmode2 goes away, this will simplify (like the 2209 // T2 version), as the LDR.i12 versions don't need the encoding 2210 // tricks for the offset value. 2211 if (isSub) { 2212 if (AddrMode == ARMII::AddrMode_i12) 2213 ImmedOffset = -ImmedOffset; 2214 else 2215 ImmedOffset |= 1 << NumBits; 2216 } 2217 ImmOp.ChangeToImmediate(ImmedOffset); 2218 Offset = 0; 2219 return true; 2220 } 2221 2222 // Otherwise, it didn't fit. Pull in what we can to simplify the immed. 2223 ImmedOffset = ImmedOffset & Mask; 2224 if (isSub) { 2225 if (AddrMode == ARMII::AddrMode_i12) 2226 ImmedOffset = -ImmedOffset; 2227 else 2228 ImmedOffset |= 1 << NumBits; 2229 } 2230 ImmOp.ChangeToImmediate(ImmedOffset); 2231 Offset &= ~(Mask*Scale); 2232 } 2233 } 2234 2235 Offset = (isSub) ? -Offset : Offset; 2236 return Offset == 0; 2237 } 2238 2239 /// analyzeCompare - For a comparison instruction, return the source registers 2240 /// in SrcReg and SrcReg2 if having two register operands, and the value it 2241 /// compares against in CmpValue. Return true if the comparison instruction 2242 /// can be analyzed. 2243 bool ARMBaseInstrInfo:: 2244 analyzeCompare(const MachineInstr *MI, unsigned &SrcReg, unsigned &SrcReg2, 2245 int &CmpMask, int &CmpValue) const { 2246 switch (MI->getOpcode()) { 2247 default: break; 2248 case ARM::CMPri: 2249 case ARM::t2CMPri: 2250 SrcReg = MI->getOperand(0).getReg(); 2251 SrcReg2 = 0; 2252 CmpMask = ~0; 2253 CmpValue = MI->getOperand(1).getImm(); 2254 return true; 2255 case ARM::CMPrr: 2256 case ARM::t2CMPrr: 2257 SrcReg = MI->getOperand(0).getReg(); 2258 SrcReg2 = MI->getOperand(1).getReg(); 2259 CmpMask = ~0; 2260 CmpValue = 0; 2261 return true; 2262 case ARM::TSTri: 2263 case ARM::t2TSTri: 2264 SrcReg = MI->getOperand(0).getReg(); 2265 SrcReg2 = 0; 2266 CmpMask = MI->getOperand(1).getImm(); 2267 CmpValue = 0; 2268 return true; 2269 } 2270 2271 return false; 2272 } 2273 2274 /// isSuitableForMask - Identify a suitable 'and' instruction that 2275 /// operates on the given source register and applies the same mask 2276 /// as a 'tst' instruction. Provide a limited look-through for copies. 2277 /// When successful, MI will hold the found instruction. 2278 static bool isSuitableForMask(MachineInstr *&MI, unsigned SrcReg, 2279 int CmpMask, bool CommonUse) { 2280 switch (MI->getOpcode()) { 2281 case ARM::ANDri: 2282 case ARM::t2ANDri: 2283 if (CmpMask != MI->getOperand(2).getImm()) 2284 return false; 2285 if (SrcReg == MI->getOperand(CommonUse ? 1 : 0).getReg()) 2286 return true; 2287 break; 2288 case ARM::COPY: { 2289 // Walk down one instruction which is potentially an 'and'. 2290 const MachineInstr &Copy = *MI; 2291 MachineBasicBlock::iterator AND( 2292 std::next(MachineBasicBlock::iterator(MI))); 2293 if (AND == MI->getParent()->end()) return false; 2294 MI = AND; 2295 return isSuitableForMask(MI, Copy.getOperand(0).getReg(), 2296 CmpMask, true); 2297 } 2298 } 2299 2300 return false; 2301 } 2302 2303 /// getSwappedCondition - assume the flags are set by MI(a,b), return 2304 /// the condition code if we modify the instructions such that flags are 2305 /// set by MI(b,a). 2306 inline static ARMCC::CondCodes getSwappedCondition(ARMCC::CondCodes CC) { 2307 switch (CC) { 2308 default: return ARMCC::AL; 2309 case ARMCC::EQ: return ARMCC::EQ; 2310 case ARMCC::NE: return ARMCC::NE; 2311 case ARMCC::HS: return ARMCC::LS; 2312 case ARMCC::LO: return ARMCC::HI; 2313 case ARMCC::HI: return ARMCC::LO; 2314 case ARMCC::LS: return ARMCC::HS; 2315 case ARMCC::GE: return ARMCC::LE; 2316 case ARMCC::LT: return ARMCC::GT; 2317 case ARMCC::GT: return ARMCC::LT; 2318 case ARMCC::LE: return ARMCC::GE; 2319 } 2320 } 2321 2322 /// isRedundantFlagInstr - check whether the first instruction, whose only 2323 /// purpose is to update flags, can be made redundant. 2324 /// CMPrr can be made redundant by SUBrr if the operands are the same. 2325 /// CMPri can be made redundant by SUBri if the operands are the same. 2326 /// This function can be extended later on. 2327 inline static bool isRedundantFlagInstr(MachineInstr *CmpI, unsigned SrcReg, 2328 unsigned SrcReg2, int ImmValue, 2329 MachineInstr *OI) { 2330 if ((CmpI->getOpcode() == ARM::CMPrr || 2331 CmpI->getOpcode() == ARM::t2CMPrr) && 2332 (OI->getOpcode() == ARM::SUBrr || 2333 OI->getOpcode() == ARM::t2SUBrr) && 2334 ((OI->getOperand(1).getReg() == SrcReg && 2335 OI->getOperand(2).getReg() == SrcReg2) || 2336 (OI->getOperand(1).getReg() == SrcReg2 && 2337 OI->getOperand(2).getReg() == SrcReg))) 2338 return true; 2339 2340 if ((CmpI->getOpcode() == ARM::CMPri || 2341 CmpI->getOpcode() == ARM::t2CMPri) && 2342 (OI->getOpcode() == ARM::SUBri || 2343 OI->getOpcode() == ARM::t2SUBri) && 2344 OI->getOperand(1).getReg() == SrcReg && 2345 OI->getOperand(2).getImm() == ImmValue) 2346 return true; 2347 return false; 2348 } 2349 2350 /// optimizeCompareInstr - Convert the instruction supplying the argument to the 2351 /// comparison into one that sets the zero bit in the flags register; 2352 /// Remove a redundant Compare instruction if an earlier instruction can set the 2353 /// flags in the same way as Compare. 2354 /// E.g. SUBrr(r1,r2) and CMPrr(r1,r2). We also handle the case where two 2355 /// operands are swapped: SUBrr(r1,r2) and CMPrr(r2,r1), by updating the 2356 /// condition code of instructions which use the flags. 2357 bool ARMBaseInstrInfo:: 2358 optimizeCompareInstr(MachineInstr *CmpInstr, unsigned SrcReg, unsigned SrcReg2, 2359 int CmpMask, int CmpValue, 2360 const MachineRegisterInfo *MRI) const { 2361 // Get the unique definition of SrcReg. 2362 MachineInstr *MI = MRI->getUniqueVRegDef(SrcReg); 2363 if (!MI) return false; 2364 2365 // Masked compares sometimes use the same register as the corresponding 'and'. 2366 if (CmpMask != ~0) { 2367 if (!isSuitableForMask(MI, SrcReg, CmpMask, false) || isPredicated(MI)) { 2368 MI = nullptr; 2369 for (MachineRegisterInfo::use_instr_iterator 2370 UI = MRI->use_instr_begin(SrcReg), UE = MRI->use_instr_end(); 2371 UI != UE; ++UI) { 2372 if (UI->getParent() != CmpInstr->getParent()) continue; 2373 MachineInstr *PotentialAND = &*UI; 2374 if (!isSuitableForMask(PotentialAND, SrcReg, CmpMask, true) || 2375 isPredicated(PotentialAND)) 2376 continue; 2377 MI = PotentialAND; 2378 break; 2379 } 2380 if (!MI) return false; 2381 } 2382 } 2383 2384 // Get ready to iterate backward from CmpInstr. 2385 MachineBasicBlock::iterator I = CmpInstr, E = MI, 2386 B = CmpInstr->getParent()->begin(); 2387 2388 // Early exit if CmpInstr is at the beginning of the BB. 2389 if (I == B) return false; 2390 2391 // There are two possible candidates which can be changed to set CPSR: 2392 // One is MI, the other is a SUB instruction. 2393 // For CMPrr(r1,r2), we are looking for SUB(r1,r2) or SUB(r2,r1). 2394 // For CMPri(r1, CmpValue), we are looking for SUBri(r1, CmpValue). 2395 MachineInstr *Sub = nullptr; 2396 if (SrcReg2 != 0) 2397 // MI is not a candidate for CMPrr. 2398 MI = nullptr; 2399 else if (MI->getParent() != CmpInstr->getParent() || CmpValue != 0) { 2400 // Conservatively refuse to convert an instruction which isn't in the same 2401 // BB as the comparison. 2402 // For CMPri w/ CmpValue != 0, a Sub may still be a candidate. 2403 // Thus we cannot return here. 2404 if (CmpInstr->getOpcode() == ARM::CMPri || 2405 CmpInstr->getOpcode() == ARM::t2CMPri) 2406 MI = nullptr; 2407 else 2408 return false; 2409 } 2410 2411 // Check that CPSR isn't set between the comparison instruction and the one we 2412 // want to change. At the same time, search for Sub. 2413 const TargetRegisterInfo *TRI = &getRegisterInfo(); 2414 --I; 2415 for (; I != E; --I) { 2416 const MachineInstr &Instr = *I; 2417 2418 if (Instr.modifiesRegister(ARM::CPSR, TRI) || 2419 Instr.readsRegister(ARM::CPSR, TRI)) 2420 // This instruction modifies or uses CPSR after the one we want to 2421 // change. We can't do this transformation. 2422 return false; 2423 2424 // Check whether CmpInstr can be made redundant by the current instruction. 2425 if (isRedundantFlagInstr(CmpInstr, SrcReg, SrcReg2, CmpValue, &*I)) { 2426 Sub = &*I; 2427 break; 2428 } 2429 2430 if (I == B) 2431 // The 'and' is below the comparison instruction. 2432 return false; 2433 } 2434 2435 // Return false if no candidates exist. 2436 if (!MI && !Sub) 2437 return false; 2438 2439 // The single candidate is called MI. 2440 if (!MI) MI = Sub; 2441 2442 // We can't use a predicated instruction - it doesn't always write the flags. 2443 if (isPredicated(MI)) 2444 return false; 2445 2446 switch (MI->getOpcode()) { 2447 default: break; 2448 case ARM::RSBrr: 2449 case ARM::RSBri: 2450 case ARM::RSCrr: 2451 case ARM::RSCri: 2452 case ARM::ADDrr: 2453 case ARM::ADDri: 2454 case ARM::ADCrr: 2455 case ARM::ADCri: 2456 case ARM::SUBrr: 2457 case ARM::SUBri: 2458 case ARM::SBCrr: 2459 case ARM::SBCri: 2460 case ARM::t2RSBri: 2461 case ARM::t2ADDrr: 2462 case ARM::t2ADDri: 2463 case ARM::t2ADCrr: 2464 case ARM::t2ADCri: 2465 case ARM::t2SUBrr: 2466 case ARM::t2SUBri: 2467 case ARM::t2SBCrr: 2468 case ARM::t2SBCri: 2469 case ARM::ANDrr: 2470 case ARM::ANDri: 2471 case ARM::t2ANDrr: 2472 case ARM::t2ANDri: 2473 case ARM::ORRrr: 2474 case ARM::ORRri: 2475 case ARM::t2ORRrr: 2476 case ARM::t2ORRri: 2477 case ARM::EORrr: 2478 case ARM::EORri: 2479 case ARM::t2EORrr: 2480 case ARM::t2EORri: { 2481 // Scan forward for the use of CPSR 2482 // When checking against MI: if it's a conditional code that requires 2483 // checking of the V bit or C bit, then this is not safe to do. 2484 // It is safe to remove CmpInstr if CPSR is redefined or killed. 2485 // If we are done with the basic block, we need to check whether CPSR is 2486 // live-out. 2487 SmallVector<std::pair<MachineOperand*, ARMCC::CondCodes>, 4> 2488 OperandsToUpdate; 2489 bool isSafe = false; 2490 I = CmpInstr; 2491 E = CmpInstr->getParent()->end(); 2492 while (!isSafe && ++I != E) { 2493 const MachineInstr &Instr = *I; 2494 for (unsigned IO = 0, EO = Instr.getNumOperands(); 2495 !isSafe && IO != EO; ++IO) { 2496 const MachineOperand &MO = Instr.getOperand(IO); 2497 if (MO.isRegMask() && MO.clobbersPhysReg(ARM::CPSR)) { 2498 isSafe = true; 2499 break; 2500 } 2501 if (!MO.isReg() || MO.getReg() != ARM::CPSR) 2502 continue; 2503 if (MO.isDef()) { 2504 isSafe = true; 2505 break; 2506 } 2507 // Condition code is after the operand before CPSR except for VSELs. 2508 ARMCC::CondCodes CC; 2509 bool IsInstrVSel = true; 2510 switch (Instr.getOpcode()) { 2511 default: 2512 IsInstrVSel = false; 2513 CC = (ARMCC::CondCodes)Instr.getOperand(IO - 1).getImm(); 2514 break; 2515 case ARM::VSELEQD: 2516 case ARM::VSELEQS: 2517 CC = ARMCC::EQ; 2518 break; 2519 case ARM::VSELGTD: 2520 case ARM::VSELGTS: 2521 CC = ARMCC::GT; 2522 break; 2523 case ARM::VSELGED: 2524 case ARM::VSELGES: 2525 CC = ARMCC::GE; 2526 break; 2527 case ARM::VSELVSS: 2528 case ARM::VSELVSD: 2529 CC = ARMCC::VS; 2530 break; 2531 } 2532 2533 if (Sub) { 2534 ARMCC::CondCodes NewCC = getSwappedCondition(CC); 2535 if (NewCC == ARMCC::AL) 2536 return false; 2537 // If we have SUB(r1, r2) and CMP(r2, r1), the condition code based 2538 // on CMP needs to be updated to be based on SUB. 2539 // Push the condition code operands to OperandsToUpdate. 2540 // If it is safe to remove CmpInstr, the condition code of these 2541 // operands will be modified. 2542 if (SrcReg2 != 0 && Sub->getOperand(1).getReg() == SrcReg2 && 2543 Sub->getOperand(2).getReg() == SrcReg) { 2544 // VSel doesn't support condition code update. 2545 if (IsInstrVSel) 2546 return false; 2547 OperandsToUpdate.push_back( 2548 std::make_pair(&((*I).getOperand(IO - 1)), NewCC)); 2549 } 2550 } else { 2551 // No Sub, so this is x = <op> y, z; cmp x, 0. 2552 switch (CC) { 2553 case ARMCC::EQ: // Z 2554 case ARMCC::NE: // Z 2555 case ARMCC::MI: // N 2556 case ARMCC::PL: // N 2557 case ARMCC::AL: // none 2558 // CPSR can be used multiple times, we should continue. 2559 break; 2560 case ARMCC::HS: // C 2561 case ARMCC::LO: // C 2562 case ARMCC::VS: // V 2563 case ARMCC::VC: // V 2564 case ARMCC::HI: // C Z 2565 case ARMCC::LS: // C Z 2566 case ARMCC::GE: // N V 2567 case ARMCC::LT: // N V 2568 case ARMCC::GT: // Z N V 2569 case ARMCC::LE: // Z N V 2570 // The instruction uses the V bit or C bit which is not safe. 2571 return false; 2572 } 2573 } 2574 } 2575 } 2576 2577 // If CPSR is not killed nor re-defined, we should check whether it is 2578 // live-out. If it is live-out, do not optimize. 2579 if (!isSafe) { 2580 MachineBasicBlock *MBB = CmpInstr->getParent(); 2581 for (MachineBasicBlock::succ_iterator SI = MBB->succ_begin(), 2582 SE = MBB->succ_end(); SI != SE; ++SI) 2583 if ((*SI)->isLiveIn(ARM::CPSR)) 2584 return false; 2585 } 2586 2587 // Toggle the optional operand to CPSR. 2588 MI->getOperand(5).setReg(ARM::CPSR); 2589 MI->getOperand(5).setIsDef(true); 2590 assert(!isPredicated(MI) && "Can't use flags from predicated instruction"); 2591 CmpInstr->eraseFromParent(); 2592 2593 // Modify the condition code of operands in OperandsToUpdate. 2594 // Since we have SUB(r1, r2) and CMP(r2, r1), the condition code needs to 2595 // be changed from r2 > r1 to r1 < r2, from r2 < r1 to r1 > r2, etc. 2596 for (unsigned i = 0, e = OperandsToUpdate.size(); i < e; i++) 2597 OperandsToUpdate[i].first->setImm(OperandsToUpdate[i].second); 2598 return true; 2599 } 2600 } 2601 2602 return false; 2603 } 2604 2605 bool ARMBaseInstrInfo::FoldImmediate(MachineInstr *UseMI, 2606 MachineInstr *DefMI, unsigned Reg, 2607 MachineRegisterInfo *MRI) const { 2608 // Fold large immediates into add, sub, or, xor. 2609 unsigned DefOpc = DefMI->getOpcode(); 2610 if (DefOpc != ARM::t2MOVi32imm && DefOpc != ARM::MOVi32imm) 2611 return false; 2612 if (!DefMI->getOperand(1).isImm()) 2613 // Could be t2MOVi32imm <ga:xx> 2614 return false; 2615 2616 if (!MRI->hasOneNonDBGUse(Reg)) 2617 return false; 2618 2619 const MCInstrDesc &DefMCID = DefMI->getDesc(); 2620 if (DefMCID.hasOptionalDef()) { 2621 unsigned NumOps = DefMCID.getNumOperands(); 2622 const MachineOperand &MO = DefMI->getOperand(NumOps-1); 2623 if (MO.getReg() == ARM::CPSR && !MO.isDead()) 2624 // If DefMI defines CPSR and it is not dead, it's obviously not safe 2625 // to delete DefMI. 2626 return false; 2627 } 2628 2629 const MCInstrDesc &UseMCID = UseMI->getDesc(); 2630 if (UseMCID.hasOptionalDef()) { 2631 unsigned NumOps = UseMCID.getNumOperands(); 2632 if (UseMI->getOperand(NumOps-1).getReg() == ARM::CPSR) 2633 // If the instruction sets the flag, do not attempt this optimization 2634 // since it may change the semantics of the code. 2635 return false; 2636 } 2637 2638 unsigned UseOpc = UseMI->getOpcode(); 2639 unsigned NewUseOpc = 0; 2640 uint32_t ImmVal = (uint32_t)DefMI->getOperand(1).getImm(); 2641 uint32_t SOImmValV1 = 0, SOImmValV2 = 0; 2642 bool Commute = false; 2643 switch (UseOpc) { 2644 default: return false; 2645 case ARM::SUBrr: 2646 case ARM::ADDrr: 2647 case ARM::ORRrr: 2648 case ARM::EORrr: 2649 case ARM::t2SUBrr: 2650 case ARM::t2ADDrr: 2651 case ARM::t2ORRrr: 2652 case ARM::t2EORrr: { 2653 Commute = UseMI->getOperand(2).getReg() != Reg; 2654 switch (UseOpc) { 2655 default: break; 2656 case ARM::SUBrr: { 2657 if (Commute) 2658 return false; 2659 ImmVal = -ImmVal; 2660 NewUseOpc = ARM::SUBri; 2661 // Fallthrough 2662 } 2663 case ARM::ADDrr: 2664 case ARM::ORRrr: 2665 case ARM::EORrr: { 2666 if (!ARM_AM::isSOImmTwoPartVal(ImmVal)) 2667 return false; 2668 SOImmValV1 = (uint32_t)ARM_AM::getSOImmTwoPartFirst(ImmVal); 2669 SOImmValV2 = (uint32_t)ARM_AM::getSOImmTwoPartSecond(ImmVal); 2670 switch (UseOpc) { 2671 default: break; 2672 case ARM::ADDrr: NewUseOpc = ARM::ADDri; break; 2673 case ARM::ORRrr: NewUseOpc = ARM::ORRri; break; 2674 case ARM::EORrr: NewUseOpc = ARM::EORri; break; 2675 } 2676 break; 2677 } 2678 case ARM::t2SUBrr: { 2679 if (Commute) 2680 return false; 2681 ImmVal = -ImmVal; 2682 NewUseOpc = ARM::t2SUBri; 2683 // Fallthrough 2684 } 2685 case ARM::t2ADDrr: 2686 case ARM::t2ORRrr: 2687 case ARM::t2EORrr: { 2688 if (!ARM_AM::isT2SOImmTwoPartVal(ImmVal)) 2689 return false; 2690 SOImmValV1 = (uint32_t)ARM_AM::getT2SOImmTwoPartFirst(ImmVal); 2691 SOImmValV2 = (uint32_t)ARM_AM::getT2SOImmTwoPartSecond(ImmVal); 2692 switch (UseOpc) { 2693 default: break; 2694 case ARM::t2ADDrr: NewUseOpc = ARM::t2ADDri; break; 2695 case ARM::t2ORRrr: NewUseOpc = ARM::t2ORRri; break; 2696 case ARM::t2EORrr: NewUseOpc = ARM::t2EORri; break; 2697 } 2698 break; 2699 } 2700 } 2701 } 2702 } 2703 2704 unsigned OpIdx = Commute ? 2 : 1; 2705 unsigned Reg1 = UseMI->getOperand(OpIdx).getReg(); 2706 bool isKill = UseMI->getOperand(OpIdx).isKill(); 2707 unsigned NewReg = MRI->createVirtualRegister(MRI->getRegClass(Reg)); 2708 AddDefaultCC(AddDefaultPred(BuildMI(*UseMI->getParent(), 2709 UseMI, UseMI->getDebugLoc(), 2710 get(NewUseOpc), NewReg) 2711 .addReg(Reg1, getKillRegState(isKill)) 2712 .addImm(SOImmValV1))); 2713 UseMI->setDesc(get(NewUseOpc)); 2714 UseMI->getOperand(1).setReg(NewReg); 2715 UseMI->getOperand(1).setIsKill(); 2716 UseMI->getOperand(2).ChangeToImmediate(SOImmValV2); 2717 DefMI->eraseFromParent(); 2718 return true; 2719 } 2720 2721 static unsigned getNumMicroOpsSwiftLdSt(const InstrItineraryData *ItinData, 2722 const MachineInstr *MI) { 2723 switch (MI->getOpcode()) { 2724 default: { 2725 const MCInstrDesc &Desc = MI->getDesc(); 2726 int UOps = ItinData->getNumMicroOps(Desc.getSchedClass()); 2727 assert(UOps >= 0 && "bad # UOps"); 2728 return UOps; 2729 } 2730 2731 case ARM::LDRrs: 2732 case ARM::LDRBrs: 2733 case ARM::STRrs: 2734 case ARM::STRBrs: { 2735 unsigned ShOpVal = MI->getOperand(3).getImm(); 2736 bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub; 2737 unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); 2738 if (!isSub && 2739 (ShImm == 0 || 2740 ((ShImm == 1 || ShImm == 2 || ShImm == 3) && 2741 ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl))) 2742 return 1; 2743 return 2; 2744 } 2745 2746 case ARM::LDRH: 2747 case ARM::STRH: { 2748 if (!MI->getOperand(2).getReg()) 2749 return 1; 2750 2751 unsigned ShOpVal = MI->getOperand(3).getImm(); 2752 bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub; 2753 unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); 2754 if (!isSub && 2755 (ShImm == 0 || 2756 ((ShImm == 1 || ShImm == 2 || ShImm == 3) && 2757 ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl))) 2758 return 1; 2759 return 2; 2760 } 2761 2762 case ARM::LDRSB: 2763 case ARM::LDRSH: 2764 return (ARM_AM::getAM3Op(MI->getOperand(3).getImm()) == ARM_AM::sub) ? 3:2; 2765 2766 case ARM::LDRSB_POST: 2767 case ARM::LDRSH_POST: { 2768 unsigned Rt = MI->getOperand(0).getReg(); 2769 unsigned Rm = MI->getOperand(3).getReg(); 2770 return (Rt == Rm) ? 4 : 3; 2771 } 2772 2773 case ARM::LDR_PRE_REG: 2774 case ARM::LDRB_PRE_REG: { 2775 unsigned Rt = MI->getOperand(0).getReg(); 2776 unsigned Rm = MI->getOperand(3).getReg(); 2777 if (Rt == Rm) 2778 return 3; 2779 unsigned ShOpVal = MI->getOperand(4).getImm(); 2780 bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub; 2781 unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); 2782 if (!isSub && 2783 (ShImm == 0 || 2784 ((ShImm == 1 || ShImm == 2 || ShImm == 3) && 2785 ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl))) 2786 return 2; 2787 return 3; 2788 } 2789 2790 case ARM::STR_PRE_REG: 2791 case ARM::STRB_PRE_REG: { 2792 unsigned ShOpVal = MI->getOperand(4).getImm(); 2793 bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub; 2794 unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); 2795 if (!isSub && 2796 (ShImm == 0 || 2797 ((ShImm == 1 || ShImm == 2 || ShImm == 3) && 2798 ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl))) 2799 return 2; 2800 return 3; 2801 } 2802 2803 case ARM::LDRH_PRE: 2804 case ARM::STRH_PRE: { 2805 unsigned Rt = MI->getOperand(0).getReg(); 2806 unsigned Rm = MI->getOperand(3).getReg(); 2807 if (!Rm) 2808 return 2; 2809 if (Rt == Rm) 2810 return 3; 2811 return (ARM_AM::getAM3Op(MI->getOperand(4).getImm()) == ARM_AM::sub) 2812 ? 3 : 2; 2813 } 2814 2815 case ARM::LDR_POST_REG: 2816 case ARM::LDRB_POST_REG: 2817 case ARM::LDRH_POST: { 2818 unsigned Rt = MI->getOperand(0).getReg(); 2819 unsigned Rm = MI->getOperand(3).getReg(); 2820 return (Rt == Rm) ? 3 : 2; 2821 } 2822 2823 case ARM::LDR_PRE_IMM: 2824 case ARM::LDRB_PRE_IMM: 2825 case ARM::LDR_POST_IMM: 2826 case ARM::LDRB_POST_IMM: 2827 case ARM::STRB_POST_IMM: 2828 case ARM::STRB_POST_REG: 2829 case ARM::STRB_PRE_IMM: 2830 case ARM::STRH_POST: 2831 case ARM::STR_POST_IMM: 2832 case ARM::STR_POST_REG: 2833 case ARM::STR_PRE_IMM: 2834 return 2; 2835 2836 case ARM::LDRSB_PRE: 2837 case ARM::LDRSH_PRE: { 2838 unsigned Rm = MI->getOperand(3).getReg(); 2839 if (Rm == 0) 2840 return 3; 2841 unsigned Rt = MI->getOperand(0).getReg(); 2842 if (Rt == Rm) 2843 return 4; 2844 unsigned ShOpVal = MI->getOperand(4).getImm(); 2845 bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub; 2846 unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); 2847 if (!isSub && 2848 (ShImm == 0 || 2849 ((ShImm == 1 || ShImm == 2 || ShImm == 3) && 2850 ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl))) 2851 return 3; 2852 return 4; 2853 } 2854 2855 case ARM::LDRD: { 2856 unsigned Rt = MI->getOperand(0).getReg(); 2857 unsigned Rn = MI->getOperand(2).getReg(); 2858 unsigned Rm = MI->getOperand(3).getReg(); 2859 if (Rm) 2860 return (ARM_AM::getAM3Op(MI->getOperand(4).getImm()) == ARM_AM::sub) ?4:3; 2861 return (Rt == Rn) ? 3 : 2; 2862 } 2863 2864 case ARM::STRD: { 2865 unsigned Rm = MI->getOperand(3).getReg(); 2866 if (Rm) 2867 return (ARM_AM::getAM3Op(MI->getOperand(4).getImm()) == ARM_AM::sub) ?4:3; 2868 return 2; 2869 } 2870 2871 case ARM::LDRD_POST: 2872 case ARM::t2LDRD_POST: 2873 return 3; 2874 2875 case ARM::STRD_POST: 2876 case ARM::t2STRD_POST: 2877 return 4; 2878 2879 case ARM::LDRD_PRE: { 2880 unsigned Rt = MI->getOperand(0).getReg(); 2881 unsigned Rn = MI->getOperand(3).getReg(); 2882 unsigned Rm = MI->getOperand(4).getReg(); 2883 if (Rm) 2884 return (ARM_AM::getAM3Op(MI->getOperand(5).getImm()) == ARM_AM::sub) ?5:4; 2885 return (Rt == Rn) ? 4 : 3; 2886 } 2887 2888 case ARM::t2LDRD_PRE: { 2889 unsigned Rt = MI->getOperand(0).getReg(); 2890 unsigned Rn = MI->getOperand(3).getReg(); 2891 return (Rt == Rn) ? 4 : 3; 2892 } 2893 2894 case ARM::STRD_PRE: { 2895 unsigned Rm = MI->getOperand(4).getReg(); 2896 if (Rm) 2897 return (ARM_AM::getAM3Op(MI->getOperand(5).getImm()) == ARM_AM::sub) ?5:4; 2898 return 3; 2899 } 2900 2901 case ARM::t2STRD_PRE: 2902 return 3; 2903 2904 case ARM::t2LDR_POST: 2905 case ARM::t2LDRB_POST: 2906 case ARM::t2LDRB_PRE: 2907 case ARM::t2LDRSBi12: 2908 case ARM::t2LDRSBi8: 2909 case ARM::t2LDRSBpci: 2910 case ARM::t2LDRSBs: 2911 case ARM::t2LDRH_POST: 2912 case ARM::t2LDRH_PRE: 2913 case ARM::t2LDRSBT: 2914 case ARM::t2LDRSB_POST: 2915 case ARM::t2LDRSB_PRE: 2916 case ARM::t2LDRSH_POST: 2917 case ARM::t2LDRSH_PRE: 2918 case ARM::t2LDRSHi12: 2919 case ARM::t2LDRSHi8: 2920 case ARM::t2LDRSHpci: 2921 case ARM::t2LDRSHs: 2922 return 2; 2923 2924 case ARM::t2LDRDi8: { 2925 unsigned Rt = MI->getOperand(0).getReg(); 2926 unsigned Rn = MI->getOperand(2).getReg(); 2927 return (Rt == Rn) ? 3 : 2; 2928 } 2929 2930 case ARM::t2STRB_POST: 2931 case ARM::t2STRB_PRE: 2932 case ARM::t2STRBs: 2933 case ARM::t2STRDi8: 2934 case ARM::t2STRH_POST: 2935 case ARM::t2STRH_PRE: 2936 case ARM::t2STRHs: 2937 case ARM::t2STR_POST: 2938 case ARM::t2STR_PRE: 2939 case ARM::t2STRs: 2940 return 2; 2941 } 2942 } 2943 2944 // Return the number of 32-bit words loaded by LDM or stored by STM. If this 2945 // can't be easily determined return 0 (missing MachineMemOperand). 2946 // 2947 // FIXME: The current MachineInstr design does not support relying on machine 2948 // mem operands to determine the width of a memory access. Instead, we expect 2949 // the target to provide this information based on the instruction opcode and 2950 // operands. However, using MachineMemOperand is the best solution now for 2951 // two reasons: 2952 // 2953 // 1) getNumMicroOps tries to infer LDM memory width from the total number of MI 2954 // operands. This is much more dangerous than using the MachineMemOperand 2955 // sizes because CodeGen passes can insert/remove optional machine operands. In 2956 // fact, it's totally incorrect for preRA passes and appears to be wrong for 2957 // postRA passes as well. 2958 // 2959 // 2) getNumLDMAddresses is only used by the scheduling machine model and any 2960 // machine model that calls this should handle the unknown (zero size) case. 2961 // 2962 // Long term, we should require a target hook that verifies MachineMemOperand 2963 // sizes during MC lowering. That target hook should be local to MC lowering 2964 // because we can't ensure that it is aware of other MI forms. Doing this will 2965 // ensure that MachineMemOperands are correctly propagated through all passes. 2966 unsigned ARMBaseInstrInfo::getNumLDMAddresses(const MachineInstr *MI) const { 2967 unsigned Size = 0; 2968 for (MachineInstr::mmo_iterator I = MI->memoperands_begin(), 2969 E = MI->memoperands_end(); I != E; ++I) { 2970 Size += (*I)->getSize(); 2971 } 2972 return Size / 4; 2973 } 2974 2975 unsigned 2976 ARMBaseInstrInfo::getNumMicroOps(const InstrItineraryData *ItinData, 2977 const MachineInstr *MI) const { 2978 if (!ItinData || ItinData->isEmpty()) 2979 return 1; 2980 2981 const MCInstrDesc &Desc = MI->getDesc(); 2982 unsigned Class = Desc.getSchedClass(); 2983 int ItinUOps = ItinData->getNumMicroOps(Class); 2984 if (ItinUOps >= 0) { 2985 if (Subtarget.isSwift() && (Desc.mayLoad() || Desc.mayStore())) 2986 return getNumMicroOpsSwiftLdSt(ItinData, MI); 2987 2988 return ItinUOps; 2989 } 2990 2991 unsigned Opc = MI->getOpcode(); 2992 switch (Opc) { 2993 default: 2994 llvm_unreachable("Unexpected multi-uops instruction!"); 2995 case ARM::VLDMQIA: 2996 case ARM::VSTMQIA: 2997 return 2; 2998 2999 // The number of uOps for load / store multiple are determined by the number 3000 // registers. 3001 // 3002 // On Cortex-A8, each pair of register loads / stores can be scheduled on the 3003 // same cycle. The scheduling for the first load / store must be done 3004 // separately by assuming the address is not 64-bit aligned. 3005 // 3006 // On Cortex-A9, the formula is simply (#reg / 2) + (#reg % 2). If the address 3007 // is not 64-bit aligned, then AGU would take an extra cycle. For VFP / NEON 3008 // load / store multiple, the formula is (#reg / 2) + (#reg % 2) + 1. 3009 case ARM::VLDMDIA: 3010 case ARM::VLDMDIA_UPD: 3011 case ARM::VLDMDDB_UPD: 3012 case ARM::VLDMSIA: 3013 case ARM::VLDMSIA_UPD: 3014 case ARM::VLDMSDB_UPD: 3015 case ARM::VSTMDIA: 3016 case ARM::VSTMDIA_UPD: 3017 case ARM::VSTMDDB_UPD: 3018 case ARM::VSTMSIA: 3019 case ARM::VSTMSIA_UPD: 3020 case ARM::VSTMSDB_UPD: { 3021 unsigned NumRegs = MI->getNumOperands() - Desc.getNumOperands(); 3022 return (NumRegs / 2) + (NumRegs % 2) + 1; 3023 } 3024 3025 case ARM::LDMIA_RET: 3026 case ARM::LDMIA: 3027 case ARM::LDMDA: 3028 case ARM::LDMDB: 3029 case ARM::LDMIB: 3030 case ARM::LDMIA_UPD: 3031 case ARM::LDMDA_UPD: 3032 case ARM::LDMDB_UPD: 3033 case ARM::LDMIB_UPD: 3034 case ARM::STMIA: 3035 case ARM::STMDA: 3036 case ARM::STMDB: 3037 case ARM::STMIB: 3038 case ARM::STMIA_UPD: 3039 case ARM::STMDA_UPD: 3040 case ARM::STMDB_UPD: 3041 case ARM::STMIB_UPD: 3042 case ARM::tLDMIA: 3043 case ARM::tLDMIA_UPD: 3044 case ARM::tSTMIA_UPD: 3045 case ARM::tPOP_RET: 3046 case ARM::tPOP: 3047 case ARM::tPUSH: 3048 case ARM::t2LDMIA_RET: 3049 case ARM::t2LDMIA: 3050 case ARM::t2LDMDB: 3051 case ARM::t2LDMIA_UPD: 3052 case ARM::t2LDMDB_UPD: 3053 case ARM::t2STMIA: 3054 case ARM::t2STMDB: 3055 case ARM::t2STMIA_UPD: 3056 case ARM::t2STMDB_UPD: { 3057 unsigned NumRegs = MI->getNumOperands() - Desc.getNumOperands() + 1; 3058 if (Subtarget.isSwift()) { 3059 int UOps = 1 + NumRegs; // One for address computation, one for each ld / st. 3060 switch (Opc) { 3061 default: 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 } else if (Subtarget.isCortexA8() || Subtarget.isCortexA7()) { 3094 if (NumRegs < 4) 3095 return 2; 3096 // 4 registers would be issued: 2, 2. 3097 // 5 registers would be issued: 2, 2, 1. 3098 int A8UOps = (NumRegs / 2); 3099 if (NumRegs % 2) 3100 ++A8UOps; 3101 return A8UOps; 3102 } else if (Subtarget.isLikeA9() || Subtarget.isSwift()) { 3103 int A9UOps = (NumRegs / 2); 3104 // If there are odd number of registers or if it's not 64-bit aligned, 3105 // then it takes an extra AGU (Address Generation Unit) cycle. 3106 if ((NumRegs % 2) || 3107 !MI->hasOneMemOperand() || 3108 (*MI->memoperands_begin())->getAlignment() < 8) 3109 ++A9UOps; 3110 return A9UOps; 3111 } else { 3112 // Assume the worst. 3113 return NumRegs; 3114 } 3115 } 3116 } 3117 } 3118 3119 int 3120 ARMBaseInstrInfo::getVLDMDefCycle(const InstrItineraryData *ItinData, 3121 const MCInstrDesc &DefMCID, 3122 unsigned DefClass, 3123 unsigned DefIdx, unsigned DefAlign) const { 3124 int RegNo = (int)(DefIdx+1) - DefMCID.getNumOperands() + 1; 3125 if (RegNo <= 0) 3126 // Def is the address writeback. 3127 return ItinData->getOperandCycle(DefClass, DefIdx); 3128 3129 int DefCycle; 3130 if (Subtarget.isCortexA8() || Subtarget.isCortexA7()) { 3131 // (regno / 2) + (regno % 2) + 1 3132 DefCycle = RegNo / 2 + 1; 3133 if (RegNo % 2) 3134 ++DefCycle; 3135 } else if (Subtarget.isLikeA9() || Subtarget.isSwift()) { 3136 DefCycle = RegNo; 3137 bool isSLoad = false; 3138 3139 switch (DefMCID.getOpcode()) { 3140 default: break; 3141 case ARM::VLDMSIA: 3142 case ARM::VLDMSIA_UPD: 3143 case ARM::VLDMSDB_UPD: 3144 isSLoad = true; 3145 break; 3146 } 3147 3148 // If there are odd number of 'S' registers or if it's not 64-bit aligned, 3149 // then it takes an extra cycle. 3150 if ((isSLoad && (RegNo % 2)) || DefAlign < 8) 3151 ++DefCycle; 3152 } else { 3153 // Assume the worst. 3154 DefCycle = RegNo + 2; 3155 } 3156 3157 return DefCycle; 3158 } 3159 3160 int 3161 ARMBaseInstrInfo::getLDMDefCycle(const InstrItineraryData *ItinData, 3162 const MCInstrDesc &DefMCID, 3163 unsigned DefClass, 3164 unsigned DefIdx, unsigned DefAlign) const { 3165 int RegNo = (int)(DefIdx+1) - DefMCID.getNumOperands() + 1; 3166 if (RegNo <= 0) 3167 // Def is the address writeback. 3168 return ItinData->getOperandCycle(DefClass, DefIdx); 3169 3170 int DefCycle; 3171 if (Subtarget.isCortexA8() || Subtarget.isCortexA7()) { 3172 // 4 registers would be issued: 1, 2, 1. 3173 // 5 registers would be issued: 1, 2, 2. 3174 DefCycle = RegNo / 2; 3175 if (DefCycle < 1) 3176 DefCycle = 1; 3177 // Result latency is issue cycle + 2: E2. 3178 DefCycle += 2; 3179 } else if (Subtarget.isLikeA9() || Subtarget.isSwift()) { 3180 DefCycle = (RegNo / 2); 3181 // If there are odd number of registers or if it's not 64-bit aligned, 3182 // then it takes an extra AGU (Address Generation Unit) cycle. 3183 if ((RegNo % 2) || DefAlign < 8) 3184 ++DefCycle; 3185 // Result latency is AGU cycles + 2. 3186 DefCycle += 2; 3187 } else { 3188 // Assume the worst. 3189 DefCycle = RegNo + 2; 3190 } 3191 3192 return DefCycle; 3193 } 3194 3195 int 3196 ARMBaseInstrInfo::getVSTMUseCycle(const InstrItineraryData *ItinData, 3197 const MCInstrDesc &UseMCID, 3198 unsigned UseClass, 3199 unsigned UseIdx, unsigned UseAlign) const { 3200 int RegNo = (int)(UseIdx+1) - UseMCID.getNumOperands() + 1; 3201 if (RegNo <= 0) 3202 return ItinData->getOperandCycle(UseClass, UseIdx); 3203 3204 int UseCycle; 3205 if (Subtarget.isCortexA8() || Subtarget.isCortexA7()) { 3206 // (regno / 2) + (regno % 2) + 1 3207 UseCycle = RegNo / 2 + 1; 3208 if (RegNo % 2) 3209 ++UseCycle; 3210 } else if (Subtarget.isLikeA9() || Subtarget.isSwift()) { 3211 UseCycle = RegNo; 3212 bool isSStore = false; 3213 3214 switch (UseMCID.getOpcode()) { 3215 default: break; 3216 case ARM::VSTMSIA: 3217 case ARM::VSTMSIA_UPD: 3218 case ARM::VSTMSDB_UPD: 3219 isSStore = true; 3220 break; 3221 } 3222 3223 // If there are odd number of 'S' registers or if it's not 64-bit aligned, 3224 // then it takes an extra cycle. 3225 if ((isSStore && (RegNo % 2)) || UseAlign < 8) 3226 ++UseCycle; 3227 } else { 3228 // Assume the worst. 3229 UseCycle = RegNo + 2; 3230 } 3231 3232 return UseCycle; 3233 } 3234 3235 int 3236 ARMBaseInstrInfo::getSTMUseCycle(const InstrItineraryData *ItinData, 3237 const MCInstrDesc &UseMCID, 3238 unsigned UseClass, 3239 unsigned UseIdx, unsigned UseAlign) const { 3240 int RegNo = (int)(UseIdx+1) - UseMCID.getNumOperands() + 1; 3241 if (RegNo <= 0) 3242 return ItinData->getOperandCycle(UseClass, UseIdx); 3243 3244 int UseCycle; 3245 if (Subtarget.isCortexA8() || Subtarget.isCortexA7()) { 3246 UseCycle = RegNo / 2; 3247 if (UseCycle < 2) 3248 UseCycle = 2; 3249 // Read in E3. 3250 UseCycle += 2; 3251 } else if (Subtarget.isLikeA9() || Subtarget.isSwift()) { 3252 UseCycle = (RegNo / 2); 3253 // If there are odd number of registers or if it's not 64-bit aligned, 3254 // then it takes an extra AGU (Address Generation Unit) cycle. 3255 if ((RegNo % 2) || UseAlign < 8) 3256 ++UseCycle; 3257 } else { 3258 // Assume the worst. 3259 UseCycle = 1; 3260 } 3261 return UseCycle; 3262 } 3263 3264 int 3265 ARMBaseInstrInfo::getOperandLatency(const InstrItineraryData *ItinData, 3266 const MCInstrDesc &DefMCID, 3267 unsigned DefIdx, unsigned DefAlign, 3268 const MCInstrDesc &UseMCID, 3269 unsigned UseIdx, unsigned UseAlign) const { 3270 unsigned DefClass = DefMCID.getSchedClass(); 3271 unsigned UseClass = UseMCID.getSchedClass(); 3272 3273 if (DefIdx < DefMCID.getNumDefs() && UseIdx < UseMCID.getNumOperands()) 3274 return ItinData->getOperandLatency(DefClass, DefIdx, UseClass, UseIdx); 3275 3276 // This may be a def / use of a variable_ops instruction, the operand 3277 // latency might be determinable dynamically. Let the target try to 3278 // figure it out. 3279 int DefCycle = -1; 3280 bool LdmBypass = false; 3281 switch (DefMCID.getOpcode()) { 3282 default: 3283 DefCycle = ItinData->getOperandCycle(DefClass, DefIdx); 3284 break; 3285 3286 case ARM::VLDMDIA: 3287 case ARM::VLDMDIA_UPD: 3288 case ARM::VLDMDDB_UPD: 3289 case ARM::VLDMSIA: 3290 case ARM::VLDMSIA_UPD: 3291 case ARM::VLDMSDB_UPD: 3292 DefCycle = getVLDMDefCycle(ItinData, DefMCID, DefClass, DefIdx, DefAlign); 3293 break; 3294 3295 case ARM::LDMIA_RET: 3296 case ARM::LDMIA: 3297 case ARM::LDMDA: 3298 case ARM::LDMDB: 3299 case ARM::LDMIB: 3300 case ARM::LDMIA_UPD: 3301 case ARM::LDMDA_UPD: 3302 case ARM::LDMDB_UPD: 3303 case ARM::LDMIB_UPD: 3304 case ARM::tLDMIA: 3305 case ARM::tLDMIA_UPD: 3306 case ARM::tPUSH: 3307 case ARM::t2LDMIA_RET: 3308 case ARM::t2LDMIA: 3309 case ARM::t2LDMDB: 3310 case ARM::t2LDMIA_UPD: 3311 case ARM::t2LDMDB_UPD: 3312 LdmBypass = 1; 3313 DefCycle = getLDMDefCycle(ItinData, DefMCID, DefClass, DefIdx, DefAlign); 3314 break; 3315 } 3316 3317 if (DefCycle == -1) 3318 // We can't seem to determine the result latency of the def, assume it's 2. 3319 DefCycle = 2; 3320 3321 int UseCycle = -1; 3322 switch (UseMCID.getOpcode()) { 3323 default: 3324 UseCycle = ItinData->getOperandCycle(UseClass, UseIdx); 3325 break; 3326 3327 case ARM::VSTMDIA: 3328 case ARM::VSTMDIA_UPD: 3329 case ARM::VSTMDDB_UPD: 3330 case ARM::VSTMSIA: 3331 case ARM::VSTMSIA_UPD: 3332 case ARM::VSTMSDB_UPD: 3333 UseCycle = getVSTMUseCycle(ItinData, UseMCID, UseClass, UseIdx, UseAlign); 3334 break; 3335 3336 case ARM::STMIA: 3337 case ARM::STMDA: 3338 case ARM::STMDB: 3339 case ARM::STMIB: 3340 case ARM::STMIA_UPD: 3341 case ARM::STMDA_UPD: 3342 case ARM::STMDB_UPD: 3343 case ARM::STMIB_UPD: 3344 case ARM::tSTMIA_UPD: 3345 case ARM::tPOP_RET: 3346 case ARM::tPOP: 3347 case ARM::t2STMIA: 3348 case ARM::t2STMDB: 3349 case ARM::t2STMIA_UPD: 3350 case ARM::t2STMDB_UPD: 3351 UseCycle = getSTMUseCycle(ItinData, UseMCID, UseClass, UseIdx, UseAlign); 3352 break; 3353 } 3354 3355 if (UseCycle == -1) 3356 // Assume it's read in the first stage. 3357 UseCycle = 1; 3358 3359 UseCycle = DefCycle - UseCycle + 1; 3360 if (UseCycle > 0) { 3361 if (LdmBypass) { 3362 // It's a variable_ops instruction so we can't use DefIdx here. Just use 3363 // first def operand. 3364 if (ItinData->hasPipelineForwarding(DefClass, DefMCID.getNumOperands()-1, 3365 UseClass, UseIdx)) 3366 --UseCycle; 3367 } else if (ItinData->hasPipelineForwarding(DefClass, DefIdx, 3368 UseClass, UseIdx)) { 3369 --UseCycle; 3370 } 3371 } 3372 3373 return UseCycle; 3374 } 3375 3376 static const MachineInstr *getBundledDefMI(const TargetRegisterInfo *TRI, 3377 const MachineInstr *MI, unsigned Reg, 3378 unsigned &DefIdx, unsigned &Dist) { 3379 Dist = 0; 3380 3381 MachineBasicBlock::const_iterator I = MI; ++I; 3382 MachineBasicBlock::const_instr_iterator II = std::prev(I.getInstrIterator()); 3383 assert(II->isInsideBundle() && "Empty bundle?"); 3384 3385 int Idx = -1; 3386 while (II->isInsideBundle()) { 3387 Idx = II->findRegisterDefOperandIdx(Reg, false, true, TRI); 3388 if (Idx != -1) 3389 break; 3390 --II; 3391 ++Dist; 3392 } 3393 3394 assert(Idx != -1 && "Cannot find bundled definition!"); 3395 DefIdx = Idx; 3396 return II; 3397 } 3398 3399 static const MachineInstr *getBundledUseMI(const TargetRegisterInfo *TRI, 3400 const MachineInstr *MI, unsigned Reg, 3401 unsigned &UseIdx, unsigned &Dist) { 3402 Dist = 0; 3403 3404 MachineBasicBlock::const_instr_iterator II = MI; ++II; 3405 assert(II->isInsideBundle() && "Empty bundle?"); 3406 MachineBasicBlock::const_instr_iterator E = MI->getParent()->instr_end(); 3407 3408 // FIXME: This doesn't properly handle multiple uses. 3409 int Idx = -1; 3410 while (II != E && II->isInsideBundle()) { 3411 Idx = II->findRegisterUseOperandIdx(Reg, false, TRI); 3412 if (Idx != -1) 3413 break; 3414 if (II->getOpcode() != ARM::t2IT) 3415 ++Dist; 3416 ++II; 3417 } 3418 3419 if (Idx == -1) { 3420 Dist = 0; 3421 return nullptr; 3422 } 3423 3424 UseIdx = Idx; 3425 return II; 3426 } 3427 3428 /// Return the number of cycles to add to (or subtract from) the static 3429 /// itinerary based on the def opcode and alignment. The caller will ensure that 3430 /// adjusted latency is at least one cycle. 3431 static int adjustDefLatency(const ARMSubtarget &Subtarget, 3432 const MachineInstr *DefMI, 3433 const MCInstrDesc *DefMCID, unsigned DefAlign) { 3434 int Adjust = 0; 3435 if (Subtarget.isCortexA8() || Subtarget.isLikeA9() || Subtarget.isCortexA7()) { 3436 // FIXME: Shifter op hack: no shift (i.e. [r +/- r]) or [r + r << 2] 3437 // variants are one cycle cheaper. 3438 switch (DefMCID->getOpcode()) { 3439 default: break; 3440 case ARM::LDRrs: 3441 case ARM::LDRBrs: { 3442 unsigned ShOpVal = DefMI->getOperand(3).getImm(); 3443 unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); 3444 if (ShImm == 0 || 3445 (ShImm == 2 && ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl)) 3446 --Adjust; 3447 break; 3448 } 3449 case ARM::t2LDRs: 3450 case ARM::t2LDRBs: 3451 case ARM::t2LDRHs: 3452 case ARM::t2LDRSHs: { 3453 // Thumb2 mode: lsl only. 3454 unsigned ShAmt = DefMI->getOperand(3).getImm(); 3455 if (ShAmt == 0 || ShAmt == 2) 3456 --Adjust; 3457 break; 3458 } 3459 } 3460 } else if (Subtarget.isSwift()) { 3461 // FIXME: Properly handle all of the latency adjustments for address 3462 // writeback. 3463 switch (DefMCID->getOpcode()) { 3464 default: break; 3465 case ARM::LDRrs: 3466 case ARM::LDRBrs: { 3467 unsigned ShOpVal = DefMI->getOperand(3).getImm(); 3468 bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub; 3469 unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); 3470 if (!isSub && 3471 (ShImm == 0 || 3472 ((ShImm == 1 || ShImm == 2 || ShImm == 3) && 3473 ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl))) 3474 Adjust -= 2; 3475 else if (!isSub && 3476 ShImm == 1 && ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsr) 3477 --Adjust; 3478 break; 3479 } 3480 case ARM::t2LDRs: 3481 case ARM::t2LDRBs: 3482 case ARM::t2LDRHs: 3483 case ARM::t2LDRSHs: { 3484 // Thumb2 mode: lsl only. 3485 unsigned ShAmt = DefMI->getOperand(3).getImm(); 3486 if (ShAmt == 0 || ShAmt == 1 || ShAmt == 2 || ShAmt == 3) 3487 Adjust -= 2; 3488 break; 3489 } 3490 } 3491 } 3492 3493 if (DefAlign < 8 && Subtarget.isLikeA9()) { 3494 switch (DefMCID->getOpcode()) { 3495 default: break; 3496 case ARM::VLD1q8: 3497 case ARM::VLD1q16: 3498 case ARM::VLD1q32: 3499 case ARM::VLD1q64: 3500 case ARM::VLD1q8wb_fixed: 3501 case ARM::VLD1q16wb_fixed: 3502 case ARM::VLD1q32wb_fixed: 3503 case ARM::VLD1q64wb_fixed: 3504 case ARM::VLD1q8wb_register: 3505 case ARM::VLD1q16wb_register: 3506 case ARM::VLD1q32wb_register: 3507 case ARM::VLD1q64wb_register: 3508 case ARM::VLD2d8: 3509 case ARM::VLD2d16: 3510 case ARM::VLD2d32: 3511 case ARM::VLD2q8: 3512 case ARM::VLD2q16: 3513 case ARM::VLD2q32: 3514 case ARM::VLD2d8wb_fixed: 3515 case ARM::VLD2d16wb_fixed: 3516 case ARM::VLD2d32wb_fixed: 3517 case ARM::VLD2q8wb_fixed: 3518 case ARM::VLD2q16wb_fixed: 3519 case ARM::VLD2q32wb_fixed: 3520 case ARM::VLD2d8wb_register: 3521 case ARM::VLD2d16wb_register: 3522 case ARM::VLD2d32wb_register: 3523 case ARM::VLD2q8wb_register: 3524 case ARM::VLD2q16wb_register: 3525 case ARM::VLD2q32wb_register: 3526 case ARM::VLD3d8: 3527 case ARM::VLD3d16: 3528 case ARM::VLD3d32: 3529 case ARM::VLD1d64T: 3530 case ARM::VLD3d8_UPD: 3531 case ARM::VLD3d16_UPD: 3532 case ARM::VLD3d32_UPD: 3533 case ARM::VLD1d64Twb_fixed: 3534 case ARM::VLD1d64Twb_register: 3535 case ARM::VLD3q8_UPD: 3536 case ARM::VLD3q16_UPD: 3537 case ARM::VLD3q32_UPD: 3538 case ARM::VLD4d8: 3539 case ARM::VLD4d16: 3540 case ARM::VLD4d32: 3541 case ARM::VLD1d64Q: 3542 case ARM::VLD4d8_UPD: 3543 case ARM::VLD4d16_UPD: 3544 case ARM::VLD4d32_UPD: 3545 case ARM::VLD1d64Qwb_fixed: 3546 case ARM::VLD1d64Qwb_register: 3547 case ARM::VLD4q8_UPD: 3548 case ARM::VLD4q16_UPD: 3549 case ARM::VLD4q32_UPD: 3550 case ARM::VLD1DUPq8: 3551 case ARM::VLD1DUPq16: 3552 case ARM::VLD1DUPq32: 3553 case ARM::VLD1DUPq8wb_fixed: 3554 case ARM::VLD1DUPq16wb_fixed: 3555 case ARM::VLD1DUPq32wb_fixed: 3556 case ARM::VLD1DUPq8wb_register: 3557 case ARM::VLD1DUPq16wb_register: 3558 case ARM::VLD1DUPq32wb_register: 3559 case ARM::VLD2DUPd8: 3560 case ARM::VLD2DUPd16: 3561 case ARM::VLD2DUPd32: 3562 case ARM::VLD2DUPd8wb_fixed: 3563 case ARM::VLD2DUPd16wb_fixed: 3564 case ARM::VLD2DUPd32wb_fixed: 3565 case ARM::VLD2DUPd8wb_register: 3566 case ARM::VLD2DUPd16wb_register: 3567 case ARM::VLD2DUPd32wb_register: 3568 case ARM::VLD4DUPd8: 3569 case ARM::VLD4DUPd16: 3570 case ARM::VLD4DUPd32: 3571 case ARM::VLD4DUPd8_UPD: 3572 case ARM::VLD4DUPd16_UPD: 3573 case ARM::VLD4DUPd32_UPD: 3574 case ARM::VLD1LNd8: 3575 case ARM::VLD1LNd16: 3576 case ARM::VLD1LNd32: 3577 case ARM::VLD1LNd8_UPD: 3578 case ARM::VLD1LNd16_UPD: 3579 case ARM::VLD1LNd32_UPD: 3580 case ARM::VLD2LNd8: 3581 case ARM::VLD2LNd16: 3582 case ARM::VLD2LNd32: 3583 case ARM::VLD2LNq16: 3584 case ARM::VLD2LNq32: 3585 case ARM::VLD2LNd8_UPD: 3586 case ARM::VLD2LNd16_UPD: 3587 case ARM::VLD2LNd32_UPD: 3588 case ARM::VLD2LNq16_UPD: 3589 case ARM::VLD2LNq32_UPD: 3590 case ARM::VLD4LNd8: 3591 case ARM::VLD4LNd16: 3592 case ARM::VLD4LNd32: 3593 case ARM::VLD4LNq16: 3594 case ARM::VLD4LNq32: 3595 case ARM::VLD4LNd8_UPD: 3596 case ARM::VLD4LNd16_UPD: 3597 case ARM::VLD4LNd32_UPD: 3598 case ARM::VLD4LNq16_UPD: 3599 case ARM::VLD4LNq32_UPD: 3600 // If the address is not 64-bit aligned, the latencies of these 3601 // instructions increases by one. 3602 ++Adjust; 3603 break; 3604 } 3605 } 3606 return Adjust; 3607 } 3608 3609 3610 3611 int 3612 ARMBaseInstrInfo::getOperandLatency(const InstrItineraryData *ItinData, 3613 const MachineInstr *DefMI, unsigned DefIdx, 3614 const MachineInstr *UseMI, 3615 unsigned UseIdx) const { 3616 // No operand latency. The caller may fall back to getInstrLatency. 3617 if (!ItinData || ItinData->isEmpty()) 3618 return -1; 3619 3620 const MachineOperand &DefMO = DefMI->getOperand(DefIdx); 3621 unsigned Reg = DefMO.getReg(); 3622 const MCInstrDesc *DefMCID = &DefMI->getDesc(); 3623 const MCInstrDesc *UseMCID = &UseMI->getDesc(); 3624 3625 unsigned DefAdj = 0; 3626 if (DefMI->isBundle()) { 3627 DefMI = getBundledDefMI(&getRegisterInfo(), DefMI, Reg, DefIdx, DefAdj); 3628 DefMCID = &DefMI->getDesc(); 3629 } 3630 if (DefMI->isCopyLike() || DefMI->isInsertSubreg() || 3631 DefMI->isRegSequence() || DefMI->isImplicitDef()) { 3632 return 1; 3633 } 3634 3635 unsigned UseAdj = 0; 3636 if (UseMI->isBundle()) { 3637 unsigned NewUseIdx; 3638 const MachineInstr *NewUseMI = getBundledUseMI(&getRegisterInfo(), UseMI, 3639 Reg, NewUseIdx, UseAdj); 3640 if (!NewUseMI) 3641 return -1; 3642 3643 UseMI = NewUseMI; 3644 UseIdx = NewUseIdx; 3645 UseMCID = &UseMI->getDesc(); 3646 } 3647 3648 if (Reg == ARM::CPSR) { 3649 if (DefMI->getOpcode() == ARM::FMSTAT) { 3650 // fpscr -> cpsr stalls over 20 cycles on A8 (and earlier?) 3651 return Subtarget.isLikeA9() ? 1 : 20; 3652 } 3653 3654 // CPSR set and branch can be paired in the same cycle. 3655 if (UseMI->isBranch()) 3656 return 0; 3657 3658 // Otherwise it takes the instruction latency (generally one). 3659 unsigned Latency = getInstrLatency(ItinData, DefMI); 3660 3661 // For Thumb2 and -Os, prefer scheduling CPSR setting instruction close to 3662 // its uses. Instructions which are otherwise scheduled between them may 3663 // incur a code size penalty (not able to use the CPSR setting 16-bit 3664 // instructions). 3665 if (Latency > 0 && Subtarget.isThumb2()) { 3666 const MachineFunction *MF = DefMI->getParent()->getParent(); 3667 if (MF->getFunction()->hasFnAttribute(Attribute::OptimizeForSize)) 3668 --Latency; 3669 } 3670 return Latency; 3671 } 3672 3673 if (DefMO.isImplicit() || UseMI->getOperand(UseIdx).isImplicit()) 3674 return -1; 3675 3676 unsigned DefAlign = DefMI->hasOneMemOperand() 3677 ? (*DefMI->memoperands_begin())->getAlignment() : 0; 3678 unsigned UseAlign = UseMI->hasOneMemOperand() 3679 ? (*UseMI->memoperands_begin())->getAlignment() : 0; 3680 3681 // Get the itinerary's latency if possible, and handle variable_ops. 3682 int Latency = getOperandLatency(ItinData, *DefMCID, DefIdx, DefAlign, 3683 *UseMCID, UseIdx, UseAlign); 3684 // Unable to find operand latency. The caller may resort to getInstrLatency. 3685 if (Latency < 0) 3686 return Latency; 3687 3688 // Adjust for IT block position. 3689 int Adj = DefAdj + UseAdj; 3690 3691 // Adjust for dynamic def-side opcode variants not captured by the itinerary. 3692 Adj += adjustDefLatency(Subtarget, DefMI, DefMCID, DefAlign); 3693 if (Adj >= 0 || (int)Latency > -Adj) { 3694 return Latency + Adj; 3695 } 3696 // Return the itinerary latency, which may be zero but not less than zero. 3697 return Latency; 3698 } 3699 3700 int 3701 ARMBaseInstrInfo::getOperandLatency(const InstrItineraryData *ItinData, 3702 SDNode *DefNode, unsigned DefIdx, 3703 SDNode *UseNode, unsigned UseIdx) const { 3704 if (!DefNode->isMachineOpcode()) 3705 return 1; 3706 3707 const MCInstrDesc &DefMCID = get(DefNode->getMachineOpcode()); 3708 3709 if (isZeroCost(DefMCID.Opcode)) 3710 return 0; 3711 3712 if (!ItinData || ItinData->isEmpty()) 3713 return DefMCID.mayLoad() ? 3 : 1; 3714 3715 if (!UseNode->isMachineOpcode()) { 3716 int Latency = ItinData->getOperandCycle(DefMCID.getSchedClass(), DefIdx); 3717 if (Subtarget.isLikeA9() || Subtarget.isSwift()) 3718 return Latency <= 2 ? 1 : Latency - 1; 3719 else 3720 return Latency <= 3 ? 1 : Latency - 2; 3721 } 3722 3723 const MCInstrDesc &UseMCID = get(UseNode->getMachineOpcode()); 3724 const MachineSDNode *DefMN = dyn_cast<MachineSDNode>(DefNode); 3725 unsigned DefAlign = !DefMN->memoperands_empty() 3726 ? (*DefMN->memoperands_begin())->getAlignment() : 0; 3727 const MachineSDNode *UseMN = dyn_cast<MachineSDNode>(UseNode); 3728 unsigned UseAlign = !UseMN->memoperands_empty() 3729 ? (*UseMN->memoperands_begin())->getAlignment() : 0; 3730 int Latency = getOperandLatency(ItinData, DefMCID, DefIdx, DefAlign, 3731 UseMCID, UseIdx, UseAlign); 3732 3733 if (Latency > 1 && 3734 (Subtarget.isCortexA8() || Subtarget.isLikeA9() || 3735 Subtarget.isCortexA7())) { 3736 // FIXME: Shifter op hack: no shift (i.e. [r +/- r]) or [r + r << 2] 3737 // variants are one cycle cheaper. 3738 switch (DefMCID.getOpcode()) { 3739 default: break; 3740 case ARM::LDRrs: 3741 case ARM::LDRBrs: { 3742 unsigned ShOpVal = 3743 cast<ConstantSDNode>(DefNode->getOperand(2))->getZExtValue(); 3744 unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); 3745 if (ShImm == 0 || 3746 (ShImm == 2 && ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl)) 3747 --Latency; 3748 break; 3749 } 3750 case ARM::t2LDRs: 3751 case ARM::t2LDRBs: 3752 case ARM::t2LDRHs: 3753 case ARM::t2LDRSHs: { 3754 // Thumb2 mode: lsl only. 3755 unsigned ShAmt = 3756 cast<ConstantSDNode>(DefNode->getOperand(2))->getZExtValue(); 3757 if (ShAmt == 0 || ShAmt == 2) 3758 --Latency; 3759 break; 3760 } 3761 } 3762 } else if (DefIdx == 0 && Latency > 2 && Subtarget.isSwift()) { 3763 // FIXME: Properly handle all of the latency adjustments for address 3764 // writeback. 3765 switch (DefMCID.getOpcode()) { 3766 default: break; 3767 case ARM::LDRrs: 3768 case ARM::LDRBrs: { 3769 unsigned ShOpVal = 3770 cast<ConstantSDNode>(DefNode->getOperand(2))->getZExtValue(); 3771 unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); 3772 if (ShImm == 0 || 3773 ((ShImm == 1 || ShImm == 2 || ShImm == 3) && 3774 ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl)) 3775 Latency -= 2; 3776 else if (ShImm == 1 && ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsr) 3777 --Latency; 3778 break; 3779 } 3780 case ARM::t2LDRs: 3781 case ARM::t2LDRBs: 3782 case ARM::t2LDRHs: 3783 case ARM::t2LDRSHs: { 3784 // Thumb2 mode: lsl 0-3 only. 3785 Latency -= 2; 3786 break; 3787 } 3788 } 3789 } 3790 3791 if (DefAlign < 8 && Subtarget.isLikeA9()) 3792 switch (DefMCID.getOpcode()) { 3793 default: break; 3794 case ARM::VLD1q8: 3795 case ARM::VLD1q16: 3796 case ARM::VLD1q32: 3797 case ARM::VLD1q64: 3798 case ARM::VLD1q8wb_register: 3799 case ARM::VLD1q16wb_register: 3800 case ARM::VLD1q32wb_register: 3801 case ARM::VLD1q64wb_register: 3802 case ARM::VLD1q8wb_fixed: 3803 case ARM::VLD1q16wb_fixed: 3804 case ARM::VLD1q32wb_fixed: 3805 case ARM::VLD1q64wb_fixed: 3806 case ARM::VLD2d8: 3807 case ARM::VLD2d16: 3808 case ARM::VLD2d32: 3809 case ARM::VLD2q8Pseudo: 3810 case ARM::VLD2q16Pseudo: 3811 case ARM::VLD2q32Pseudo: 3812 case ARM::VLD2d8wb_fixed: 3813 case ARM::VLD2d16wb_fixed: 3814 case ARM::VLD2d32wb_fixed: 3815 case ARM::VLD2q8PseudoWB_fixed: 3816 case ARM::VLD2q16PseudoWB_fixed: 3817 case ARM::VLD2q32PseudoWB_fixed: 3818 case ARM::VLD2d8wb_register: 3819 case ARM::VLD2d16wb_register: 3820 case ARM::VLD2d32wb_register: 3821 case ARM::VLD2q8PseudoWB_register: 3822 case ARM::VLD2q16PseudoWB_register: 3823 case ARM::VLD2q32PseudoWB_register: 3824 case ARM::VLD3d8Pseudo: 3825 case ARM::VLD3d16Pseudo: 3826 case ARM::VLD3d32Pseudo: 3827 case ARM::VLD1d64TPseudo: 3828 case ARM::VLD1d64TPseudoWB_fixed: 3829 case ARM::VLD3d8Pseudo_UPD: 3830 case ARM::VLD3d16Pseudo_UPD: 3831 case ARM::VLD3d32Pseudo_UPD: 3832 case ARM::VLD3q8Pseudo_UPD: 3833 case ARM::VLD3q16Pseudo_UPD: 3834 case ARM::VLD3q32Pseudo_UPD: 3835 case ARM::VLD3q8oddPseudo: 3836 case ARM::VLD3q16oddPseudo: 3837 case ARM::VLD3q32oddPseudo: 3838 case ARM::VLD3q8oddPseudo_UPD: 3839 case ARM::VLD3q16oddPseudo_UPD: 3840 case ARM::VLD3q32oddPseudo_UPD: 3841 case ARM::VLD4d8Pseudo: 3842 case ARM::VLD4d16Pseudo: 3843 case ARM::VLD4d32Pseudo: 3844 case ARM::VLD1d64QPseudo: 3845 case ARM::VLD1d64QPseudoWB_fixed: 3846 case ARM::VLD4d8Pseudo_UPD: 3847 case ARM::VLD4d16Pseudo_UPD: 3848 case ARM::VLD4d32Pseudo_UPD: 3849 case ARM::VLD4q8Pseudo_UPD: 3850 case ARM::VLD4q16Pseudo_UPD: 3851 case ARM::VLD4q32Pseudo_UPD: 3852 case ARM::VLD4q8oddPseudo: 3853 case ARM::VLD4q16oddPseudo: 3854 case ARM::VLD4q32oddPseudo: 3855 case ARM::VLD4q8oddPseudo_UPD: 3856 case ARM::VLD4q16oddPseudo_UPD: 3857 case ARM::VLD4q32oddPseudo_UPD: 3858 case ARM::VLD1DUPq8: 3859 case ARM::VLD1DUPq16: 3860 case ARM::VLD1DUPq32: 3861 case ARM::VLD1DUPq8wb_fixed: 3862 case ARM::VLD1DUPq16wb_fixed: 3863 case ARM::VLD1DUPq32wb_fixed: 3864 case ARM::VLD1DUPq8wb_register: 3865 case ARM::VLD1DUPq16wb_register: 3866 case ARM::VLD1DUPq32wb_register: 3867 case ARM::VLD2DUPd8: 3868 case ARM::VLD2DUPd16: 3869 case ARM::VLD2DUPd32: 3870 case ARM::VLD2DUPd8wb_fixed: 3871 case ARM::VLD2DUPd16wb_fixed: 3872 case ARM::VLD2DUPd32wb_fixed: 3873 case ARM::VLD2DUPd8wb_register: 3874 case ARM::VLD2DUPd16wb_register: 3875 case ARM::VLD2DUPd32wb_register: 3876 case ARM::VLD4DUPd8Pseudo: 3877 case ARM::VLD4DUPd16Pseudo: 3878 case ARM::VLD4DUPd32Pseudo: 3879 case ARM::VLD4DUPd8Pseudo_UPD: 3880 case ARM::VLD4DUPd16Pseudo_UPD: 3881 case ARM::VLD4DUPd32Pseudo_UPD: 3882 case ARM::VLD1LNq8Pseudo: 3883 case ARM::VLD1LNq16Pseudo: 3884 case ARM::VLD1LNq32Pseudo: 3885 case ARM::VLD1LNq8Pseudo_UPD: 3886 case ARM::VLD1LNq16Pseudo_UPD: 3887 case ARM::VLD1LNq32Pseudo_UPD: 3888 case ARM::VLD2LNd8Pseudo: 3889 case ARM::VLD2LNd16Pseudo: 3890 case ARM::VLD2LNd32Pseudo: 3891 case ARM::VLD2LNq16Pseudo: 3892 case ARM::VLD2LNq32Pseudo: 3893 case ARM::VLD2LNd8Pseudo_UPD: 3894 case ARM::VLD2LNd16Pseudo_UPD: 3895 case ARM::VLD2LNd32Pseudo_UPD: 3896 case ARM::VLD2LNq16Pseudo_UPD: 3897 case ARM::VLD2LNq32Pseudo_UPD: 3898 case ARM::VLD4LNd8Pseudo: 3899 case ARM::VLD4LNd16Pseudo: 3900 case ARM::VLD4LNd32Pseudo: 3901 case ARM::VLD4LNq16Pseudo: 3902 case ARM::VLD4LNq32Pseudo: 3903 case ARM::VLD4LNd8Pseudo_UPD: 3904 case ARM::VLD4LNd16Pseudo_UPD: 3905 case ARM::VLD4LNd32Pseudo_UPD: 3906 case ARM::VLD4LNq16Pseudo_UPD: 3907 case ARM::VLD4LNq32Pseudo_UPD: 3908 // If the address is not 64-bit aligned, the latencies of these 3909 // instructions increases by one. 3910 ++Latency; 3911 break; 3912 } 3913 3914 return Latency; 3915 } 3916 3917 unsigned ARMBaseInstrInfo::getPredicationCost(const MachineInstr *MI) const { 3918 if (MI->isCopyLike() || MI->isInsertSubreg() || 3919 MI->isRegSequence() || MI->isImplicitDef()) 3920 return 0; 3921 3922 if (MI->isBundle()) 3923 return 0; 3924 3925 const MCInstrDesc &MCID = MI->getDesc(); 3926 3927 if (MCID.isCall() || MCID.hasImplicitDefOfPhysReg(ARM::CPSR)) { 3928 // When predicated, CPSR is an additional source operand for CPSR updating 3929 // instructions, this apparently increases their latencies. 3930 return 1; 3931 } 3932 return 0; 3933 } 3934 3935 unsigned ARMBaseInstrInfo::getInstrLatency(const InstrItineraryData *ItinData, 3936 const MachineInstr *MI, 3937 unsigned *PredCost) const { 3938 if (MI->isCopyLike() || MI->isInsertSubreg() || 3939 MI->isRegSequence() || MI->isImplicitDef()) 3940 return 1; 3941 3942 // An instruction scheduler typically runs on unbundled instructions, however 3943 // other passes may query the latency of a bundled instruction. 3944 if (MI->isBundle()) { 3945 unsigned Latency = 0; 3946 MachineBasicBlock::const_instr_iterator I = MI; 3947 MachineBasicBlock::const_instr_iterator E = MI->getParent()->instr_end(); 3948 while (++I != E && I->isInsideBundle()) { 3949 if (I->getOpcode() != ARM::t2IT) 3950 Latency += getInstrLatency(ItinData, I, PredCost); 3951 } 3952 return Latency; 3953 } 3954 3955 const MCInstrDesc &MCID = MI->getDesc(); 3956 if (PredCost && (MCID.isCall() || MCID.hasImplicitDefOfPhysReg(ARM::CPSR))) { 3957 // When predicated, CPSR is an additional source operand for CPSR updating 3958 // instructions, this apparently increases their latencies. 3959 *PredCost = 1; 3960 } 3961 // Be sure to call getStageLatency for an empty itinerary in case it has a 3962 // valid MinLatency property. 3963 if (!ItinData) 3964 return MI->mayLoad() ? 3 : 1; 3965 3966 unsigned Class = MCID.getSchedClass(); 3967 3968 // For instructions with variable uops, use uops as latency. 3969 if (!ItinData->isEmpty() && ItinData->getNumMicroOps(Class) < 0) 3970 return getNumMicroOps(ItinData, MI); 3971 3972 // For the common case, fall back on the itinerary's latency. 3973 unsigned Latency = ItinData->getStageLatency(Class); 3974 3975 // Adjust for dynamic def-side opcode variants not captured by the itinerary. 3976 unsigned DefAlign = MI->hasOneMemOperand() 3977 ? (*MI->memoperands_begin())->getAlignment() : 0; 3978 int Adj = adjustDefLatency(Subtarget, MI, &MCID, DefAlign); 3979 if (Adj >= 0 || (int)Latency > -Adj) { 3980 return Latency + Adj; 3981 } 3982 return Latency; 3983 } 3984 3985 int ARMBaseInstrInfo::getInstrLatency(const InstrItineraryData *ItinData, 3986 SDNode *Node) const { 3987 if (!Node->isMachineOpcode()) 3988 return 1; 3989 3990 if (!ItinData || ItinData->isEmpty()) 3991 return 1; 3992 3993 unsigned Opcode = Node->getMachineOpcode(); 3994 switch (Opcode) { 3995 default: 3996 return ItinData->getStageLatency(get(Opcode).getSchedClass()); 3997 case ARM::VLDMQIA: 3998 case ARM::VSTMQIA: 3999 return 2; 4000 } 4001 } 4002 4003 bool ARMBaseInstrInfo:: 4004 hasHighOperandLatency(const InstrItineraryData *ItinData, 4005 const MachineRegisterInfo *MRI, 4006 const MachineInstr *DefMI, unsigned DefIdx, 4007 const MachineInstr *UseMI, unsigned UseIdx) const { 4008 unsigned DDomain = DefMI->getDesc().TSFlags & ARMII::DomainMask; 4009 unsigned UDomain = UseMI->getDesc().TSFlags & ARMII::DomainMask; 4010 if (Subtarget.isCortexA8() && 4011 (DDomain == ARMII::DomainVFP || UDomain == ARMII::DomainVFP)) 4012 // CortexA8 VFP instructions are not pipelined. 4013 return true; 4014 4015 // Hoist VFP / NEON instructions with 4 or higher latency. 4016 int Latency = computeOperandLatency(ItinData, DefMI, DefIdx, UseMI, UseIdx); 4017 if (Latency < 0) 4018 Latency = getInstrLatency(ItinData, DefMI); 4019 if (Latency <= 3) 4020 return false; 4021 return DDomain == ARMII::DomainVFP || DDomain == ARMII::DomainNEON || 4022 UDomain == ARMII::DomainVFP || UDomain == ARMII::DomainNEON; 4023 } 4024 4025 bool ARMBaseInstrInfo:: 4026 hasLowDefLatency(const InstrItineraryData *ItinData, 4027 const MachineInstr *DefMI, unsigned DefIdx) const { 4028 if (!ItinData || ItinData->isEmpty()) 4029 return false; 4030 4031 unsigned DDomain = DefMI->getDesc().TSFlags & ARMII::DomainMask; 4032 if (DDomain == ARMII::DomainGeneral) { 4033 unsigned DefClass = DefMI->getDesc().getSchedClass(); 4034 int DefCycle = ItinData->getOperandCycle(DefClass, DefIdx); 4035 return (DefCycle != -1 && DefCycle <= 2); 4036 } 4037 return false; 4038 } 4039 4040 bool ARMBaseInstrInfo::verifyInstruction(const MachineInstr *MI, 4041 StringRef &ErrInfo) const { 4042 if (convertAddSubFlagsOpcode(MI->getOpcode())) { 4043 ErrInfo = "Pseudo flag setting opcodes only exist in Selection DAG"; 4044 return false; 4045 } 4046 return true; 4047 } 4048 4049 // LoadStackGuard has so far only been implemented for MachO. Different code 4050 // sequence is needed for other targets. 4051 void ARMBaseInstrInfo::expandLoadStackGuardBase(MachineBasicBlock::iterator MI, 4052 unsigned LoadImmOpc, 4053 unsigned LoadOpc, 4054 Reloc::Model RM) const { 4055 MachineBasicBlock &MBB = *MI->getParent(); 4056 DebugLoc DL = MI->getDebugLoc(); 4057 unsigned Reg = MI->getOperand(0).getReg(); 4058 const GlobalValue *GV = 4059 cast<GlobalValue>((*MI->memoperands_begin())->getValue()); 4060 MachineInstrBuilder MIB; 4061 4062 BuildMI(MBB, MI, DL, get(LoadImmOpc), Reg) 4063 .addGlobalAddress(GV, 0, ARMII::MO_NONLAZY); 4064 4065 if (Subtarget.GVIsIndirectSymbol(GV, RM)) { 4066 MIB = BuildMI(MBB, MI, DL, get(LoadOpc), Reg); 4067 MIB.addReg(Reg, RegState::Kill).addImm(0); 4068 unsigned Flag = MachineMemOperand::MOLoad | MachineMemOperand::MOInvariant; 4069 MachineMemOperand *MMO = MBB.getParent()-> 4070 getMachineMemOperand(MachinePointerInfo::getGOT(), Flag, 4, 4); 4071 MIB.addMemOperand(MMO); 4072 AddDefaultPred(MIB); 4073 } 4074 4075 MIB = BuildMI(MBB, MI, DL, get(LoadOpc), Reg); 4076 MIB.addReg(Reg, RegState::Kill).addImm(0); 4077 MIB.setMemRefs(MI->memoperands_begin(), MI->memoperands_end()); 4078 AddDefaultPred(MIB); 4079 } 4080 4081 bool 4082 ARMBaseInstrInfo::isFpMLxInstruction(unsigned Opcode, unsigned &MulOpc, 4083 unsigned &AddSubOpc, 4084 bool &NegAcc, bool &HasLane) const { 4085 DenseMap<unsigned, unsigned>::const_iterator I = MLxEntryMap.find(Opcode); 4086 if (I == MLxEntryMap.end()) 4087 return false; 4088 4089 const ARM_MLxEntry &Entry = ARM_MLxTable[I->second]; 4090 MulOpc = Entry.MulOpc; 4091 AddSubOpc = Entry.AddSubOpc; 4092 NegAcc = Entry.NegAcc; 4093 HasLane = Entry.HasLane; 4094 return true; 4095 } 4096 4097 //===----------------------------------------------------------------------===// 4098 // Execution domains. 4099 //===----------------------------------------------------------------------===// 4100 // 4101 // Some instructions go down the NEON pipeline, some go down the VFP pipeline, 4102 // and some can go down both. The vmov instructions go down the VFP pipeline, 4103 // but they can be changed to vorr equivalents that are executed by the NEON 4104 // pipeline. 4105 // 4106 // We use the following execution domain numbering: 4107 // 4108 enum ARMExeDomain { 4109 ExeGeneric = 0, 4110 ExeVFP = 1, 4111 ExeNEON = 2 4112 }; 4113 // 4114 // Also see ARMInstrFormats.td and Domain* enums in ARMBaseInfo.h 4115 // 4116 std::pair<uint16_t, uint16_t> 4117 ARMBaseInstrInfo::getExecutionDomain(const MachineInstr *MI) const { 4118 // VMOVD, VMOVRS and VMOVSR are VFP instructions, but can be changed to NEON 4119 // if they are not predicated. 4120 if (MI->getOpcode() == ARM::VMOVD && !isPredicated(MI)) 4121 return std::make_pair(ExeVFP, (1<<ExeVFP) | (1<<ExeNEON)); 4122 4123 // CortexA9 is particularly picky about mixing the two and wants these 4124 // converted. 4125 if (Subtarget.isCortexA9() && !isPredicated(MI) && 4126 (MI->getOpcode() == ARM::VMOVRS || 4127 MI->getOpcode() == ARM::VMOVSR || 4128 MI->getOpcode() == ARM::VMOVS)) 4129 return std::make_pair(ExeVFP, (1<<ExeVFP) | (1<<ExeNEON)); 4130 4131 // No other instructions can be swizzled, so just determine their domain. 4132 unsigned Domain = MI->getDesc().TSFlags & ARMII::DomainMask; 4133 4134 if (Domain & ARMII::DomainNEON) 4135 return std::make_pair(ExeNEON, 0); 4136 4137 // Certain instructions can go either way on Cortex-A8. 4138 // Treat them as NEON instructions. 4139 if ((Domain & ARMII::DomainNEONA8) && Subtarget.isCortexA8()) 4140 return std::make_pair(ExeNEON, 0); 4141 4142 if (Domain & ARMII::DomainVFP) 4143 return std::make_pair(ExeVFP, 0); 4144 4145 return std::make_pair(ExeGeneric, 0); 4146 } 4147 4148 static unsigned getCorrespondingDRegAndLane(const TargetRegisterInfo *TRI, 4149 unsigned SReg, unsigned &Lane) { 4150 unsigned DReg = TRI->getMatchingSuperReg(SReg, ARM::ssub_0, &ARM::DPRRegClass); 4151 Lane = 0; 4152 4153 if (DReg != ARM::NoRegister) 4154 return DReg; 4155 4156 Lane = 1; 4157 DReg = TRI->getMatchingSuperReg(SReg, ARM::ssub_1, &ARM::DPRRegClass); 4158 4159 assert(DReg && "S-register with no D super-register?"); 4160 return DReg; 4161 } 4162 4163 /// getImplicitSPRUseForDPRUse - Given a use of a DPR register and lane, 4164 /// set ImplicitSReg to a register number that must be marked as implicit-use or 4165 /// zero if no register needs to be defined as implicit-use. 4166 /// 4167 /// If the function cannot determine if an SPR should be marked implicit use or 4168 /// not, it returns false. 4169 /// 4170 /// This function handles cases where an instruction is being modified from taking 4171 /// an SPR to a DPR[Lane]. A use of the DPR is being added, which may conflict 4172 /// with an earlier def of an SPR corresponding to DPR[Lane^1] (i.e. the other 4173 /// lane of the DPR). 4174 /// 4175 /// If the other SPR is defined, an implicit-use of it should be added. Else, 4176 /// (including the case where the DPR itself is defined), it should not. 4177 /// 4178 static bool getImplicitSPRUseForDPRUse(const TargetRegisterInfo *TRI, 4179 MachineInstr *MI, 4180 unsigned DReg, unsigned Lane, 4181 unsigned &ImplicitSReg) { 4182 // If the DPR is defined or used already, the other SPR lane will be chained 4183 // correctly, so there is nothing to be done. 4184 if (MI->definesRegister(DReg, TRI) || MI->readsRegister(DReg, TRI)) { 4185 ImplicitSReg = 0; 4186 return true; 4187 } 4188 4189 // Otherwise we need to go searching to see if the SPR is set explicitly. 4190 ImplicitSReg = TRI->getSubReg(DReg, 4191 (Lane & 1) ? ARM::ssub_0 : ARM::ssub_1); 4192 MachineBasicBlock::LivenessQueryResult LQR = 4193 MI->getParent()->computeRegisterLiveness(TRI, ImplicitSReg, MI); 4194 4195 if (LQR == MachineBasicBlock::LQR_Live) 4196 return true; 4197 else if (LQR == MachineBasicBlock::LQR_Unknown) 4198 return false; 4199 4200 // If the register is known not to be live, there is no need to add an 4201 // implicit-use. 4202 ImplicitSReg = 0; 4203 return true; 4204 } 4205 4206 void 4207 ARMBaseInstrInfo::setExecutionDomain(MachineInstr *MI, unsigned Domain) const { 4208 unsigned DstReg, SrcReg, DReg; 4209 unsigned Lane; 4210 MachineInstrBuilder MIB(*MI->getParent()->getParent(), MI); 4211 const TargetRegisterInfo *TRI = &getRegisterInfo(); 4212 switch (MI->getOpcode()) { 4213 default: 4214 llvm_unreachable("cannot handle opcode!"); 4215 break; 4216 case ARM::VMOVD: 4217 if (Domain != ExeNEON) 4218 break; 4219 4220 // Zap the predicate operands. 4221 assert(!isPredicated(MI) && "Cannot predicate a VORRd"); 4222 4223 // Source instruction is %DDst = VMOVD %DSrc, 14, %noreg (; implicits) 4224 DstReg = MI->getOperand(0).getReg(); 4225 SrcReg = MI->getOperand(1).getReg(); 4226 4227 for (unsigned i = MI->getDesc().getNumOperands(); i; --i) 4228 MI->RemoveOperand(i-1); 4229 4230 // Change to a %DDst = VORRd %DSrc, %DSrc, 14, %noreg (; implicits) 4231 MI->setDesc(get(ARM::VORRd)); 4232 AddDefaultPred(MIB.addReg(DstReg, RegState::Define) 4233 .addReg(SrcReg) 4234 .addReg(SrcReg)); 4235 break; 4236 case ARM::VMOVRS: 4237 if (Domain != ExeNEON) 4238 break; 4239 assert(!isPredicated(MI) && "Cannot predicate a VGETLN"); 4240 4241 // Source instruction is %RDst = VMOVRS %SSrc, 14, %noreg (; implicits) 4242 DstReg = MI->getOperand(0).getReg(); 4243 SrcReg = MI->getOperand(1).getReg(); 4244 4245 for (unsigned i = MI->getDesc().getNumOperands(); i; --i) 4246 MI->RemoveOperand(i-1); 4247 4248 DReg = getCorrespondingDRegAndLane(TRI, SrcReg, Lane); 4249 4250 // Convert to %RDst = VGETLNi32 %DSrc, Lane, 14, %noreg (; imps) 4251 // Note that DSrc has been widened and the other lane may be undef, which 4252 // contaminates the entire register. 4253 MI->setDesc(get(ARM::VGETLNi32)); 4254 AddDefaultPred(MIB.addReg(DstReg, RegState::Define) 4255 .addReg(DReg, RegState::Undef) 4256 .addImm(Lane)); 4257 4258 // The old source should be an implicit use, otherwise we might think it 4259 // was dead before here. 4260 MIB.addReg(SrcReg, RegState::Implicit); 4261 break; 4262 case ARM::VMOVSR: { 4263 if (Domain != ExeNEON) 4264 break; 4265 assert(!isPredicated(MI) && "Cannot predicate a VSETLN"); 4266 4267 // Source instruction is %SDst = VMOVSR %RSrc, 14, %noreg (; implicits) 4268 DstReg = MI->getOperand(0).getReg(); 4269 SrcReg = MI->getOperand(1).getReg(); 4270 4271 DReg = getCorrespondingDRegAndLane(TRI, DstReg, Lane); 4272 4273 unsigned ImplicitSReg; 4274 if (!getImplicitSPRUseForDPRUse(TRI, MI, DReg, Lane, ImplicitSReg)) 4275 break; 4276 4277 for (unsigned i = MI->getDesc().getNumOperands(); i; --i) 4278 MI->RemoveOperand(i-1); 4279 4280 // Convert to %DDst = VSETLNi32 %DDst, %RSrc, Lane, 14, %noreg (; imps) 4281 // Again DDst may be undefined at the beginning of this instruction. 4282 MI->setDesc(get(ARM::VSETLNi32)); 4283 MIB.addReg(DReg, RegState::Define) 4284 .addReg(DReg, getUndefRegState(!MI->readsRegister(DReg, TRI))) 4285 .addReg(SrcReg) 4286 .addImm(Lane); 4287 AddDefaultPred(MIB); 4288 4289 // The narrower destination must be marked as set to keep previous chains 4290 // in place. 4291 MIB.addReg(DstReg, RegState::Define | RegState::Implicit); 4292 if (ImplicitSReg != 0) 4293 MIB.addReg(ImplicitSReg, RegState::Implicit); 4294 break; 4295 } 4296 case ARM::VMOVS: { 4297 if (Domain != ExeNEON) 4298 break; 4299 4300 // Source instruction is %SDst = VMOVS %SSrc, 14, %noreg (; implicits) 4301 DstReg = MI->getOperand(0).getReg(); 4302 SrcReg = MI->getOperand(1).getReg(); 4303 4304 unsigned DstLane = 0, SrcLane = 0, DDst, DSrc; 4305 DDst = getCorrespondingDRegAndLane(TRI, DstReg, DstLane); 4306 DSrc = getCorrespondingDRegAndLane(TRI, SrcReg, SrcLane); 4307 4308 unsigned ImplicitSReg; 4309 if (!getImplicitSPRUseForDPRUse(TRI, MI, DSrc, SrcLane, ImplicitSReg)) 4310 break; 4311 4312 for (unsigned i = MI->getDesc().getNumOperands(); i; --i) 4313 MI->RemoveOperand(i-1); 4314 4315 if (DSrc == DDst) { 4316 // Destination can be: 4317 // %DDst = VDUPLN32d %DDst, Lane, 14, %noreg (; implicits) 4318 MI->setDesc(get(ARM::VDUPLN32d)); 4319 MIB.addReg(DDst, RegState::Define) 4320 .addReg(DDst, getUndefRegState(!MI->readsRegister(DDst, TRI))) 4321 .addImm(SrcLane); 4322 AddDefaultPred(MIB); 4323 4324 // Neither the source or the destination are naturally represented any 4325 // more, so add them in manually. 4326 MIB.addReg(DstReg, RegState::Implicit | RegState::Define); 4327 MIB.addReg(SrcReg, RegState::Implicit); 4328 if (ImplicitSReg != 0) 4329 MIB.addReg(ImplicitSReg, RegState::Implicit); 4330 break; 4331 } 4332 4333 // In general there's no single instruction that can perform an S <-> S 4334 // move in NEON space, but a pair of VEXT instructions *can* do the 4335 // job. It turns out that the VEXTs needed will only use DSrc once, with 4336 // the position based purely on the combination of lane-0 and lane-1 4337 // involved. For example 4338 // vmov s0, s2 -> vext.32 d0, d0, d1, #1 vext.32 d0, d0, d0, #1 4339 // vmov s1, s3 -> vext.32 d0, d1, d0, #1 vext.32 d0, d0, d0, #1 4340 // vmov s0, s3 -> vext.32 d0, d0, d0, #1 vext.32 d0, d1, d0, #1 4341 // vmov s1, s2 -> vext.32 d0, d0, d0, #1 vext.32 d0, d0, d1, #1 4342 // 4343 // Pattern of the MachineInstrs is: 4344 // %DDst = VEXTd32 %DSrc1, %DSrc2, Lane, 14, %noreg (;implicits) 4345 MachineInstrBuilder NewMIB; 4346 NewMIB = BuildMI(*MI->getParent(), MI, MI->getDebugLoc(), 4347 get(ARM::VEXTd32), DDst); 4348 4349 // On the first instruction, both DSrc and DDst may be <undef> if present. 4350 // Specifically when the original instruction didn't have them as an 4351 // <imp-use>. 4352 unsigned CurReg = SrcLane == 1 && DstLane == 1 ? DSrc : DDst; 4353 bool CurUndef = !MI->readsRegister(CurReg, TRI); 4354 NewMIB.addReg(CurReg, getUndefRegState(CurUndef)); 4355 4356 CurReg = SrcLane == 0 && DstLane == 0 ? DSrc : DDst; 4357 CurUndef = !MI->readsRegister(CurReg, TRI); 4358 NewMIB.addReg(CurReg, getUndefRegState(CurUndef)); 4359 4360 NewMIB.addImm(1); 4361 AddDefaultPred(NewMIB); 4362 4363 if (SrcLane == DstLane) 4364 NewMIB.addReg(SrcReg, RegState::Implicit); 4365 4366 MI->setDesc(get(ARM::VEXTd32)); 4367 MIB.addReg(DDst, RegState::Define); 4368 4369 // On the second instruction, DDst has definitely been defined above, so 4370 // it is not <undef>. DSrc, if present, can be <undef> as above. 4371 CurReg = SrcLane == 1 && DstLane == 0 ? DSrc : DDst; 4372 CurUndef = CurReg == DSrc && !MI->readsRegister(CurReg, TRI); 4373 MIB.addReg(CurReg, getUndefRegState(CurUndef)); 4374 4375 CurReg = SrcLane == 0 && DstLane == 1 ? DSrc : DDst; 4376 CurUndef = CurReg == DSrc && !MI->readsRegister(CurReg, TRI); 4377 MIB.addReg(CurReg, getUndefRegState(CurUndef)); 4378 4379 MIB.addImm(1); 4380 AddDefaultPred(MIB); 4381 4382 if (SrcLane != DstLane) 4383 MIB.addReg(SrcReg, RegState::Implicit); 4384 4385 // As before, the original destination is no longer represented, add it 4386 // implicitly. 4387 MIB.addReg(DstReg, RegState::Define | RegState::Implicit); 4388 if (ImplicitSReg != 0) 4389 MIB.addReg(ImplicitSReg, RegState::Implicit); 4390 break; 4391 } 4392 } 4393 4394 } 4395 4396 //===----------------------------------------------------------------------===// 4397 // Partial register updates 4398 //===----------------------------------------------------------------------===// 4399 // 4400 // Swift renames NEON registers with 64-bit granularity. That means any 4401 // instruction writing an S-reg implicitly reads the containing D-reg. The 4402 // problem is mostly avoided by translating f32 operations to v2f32 operations 4403 // on D-registers, but f32 loads are still a problem. 4404 // 4405 // These instructions can load an f32 into a NEON register: 4406 // 4407 // VLDRS - Only writes S, partial D update. 4408 // VLD1LNd32 - Writes all D-regs, explicit partial D update, 2 uops. 4409 // VLD1DUPd32 - Writes all D-regs, no partial reg update, 2 uops. 4410 // 4411 // FCONSTD can be used as a dependency-breaking instruction. 4412 unsigned ARMBaseInstrInfo:: 4413 getPartialRegUpdateClearance(const MachineInstr *MI, 4414 unsigned OpNum, 4415 const TargetRegisterInfo *TRI) const { 4416 if (!SwiftPartialUpdateClearance || 4417 !(Subtarget.isSwift() || Subtarget.isCortexA15())) 4418 return 0; 4419 4420 assert(TRI && "Need TRI instance"); 4421 4422 const MachineOperand &MO = MI->getOperand(OpNum); 4423 if (MO.readsReg()) 4424 return 0; 4425 unsigned Reg = MO.getReg(); 4426 int UseOp = -1; 4427 4428 switch(MI->getOpcode()) { 4429 // Normal instructions writing only an S-register. 4430 case ARM::VLDRS: 4431 case ARM::FCONSTS: 4432 case ARM::VMOVSR: 4433 case ARM::VMOVv8i8: 4434 case ARM::VMOVv4i16: 4435 case ARM::VMOVv2i32: 4436 case ARM::VMOVv2f32: 4437 case ARM::VMOVv1i64: 4438 UseOp = MI->findRegisterUseOperandIdx(Reg, false, TRI); 4439 break; 4440 4441 // Explicitly reads the dependency. 4442 case ARM::VLD1LNd32: 4443 UseOp = 3; 4444 break; 4445 default: 4446 return 0; 4447 } 4448 4449 // If this instruction actually reads a value from Reg, there is no unwanted 4450 // dependency. 4451 if (UseOp != -1 && MI->getOperand(UseOp).readsReg()) 4452 return 0; 4453 4454 // We must be able to clobber the whole D-reg. 4455 if (TargetRegisterInfo::isVirtualRegister(Reg)) { 4456 // Virtual register must be a foo:ssub_0<def,undef> operand. 4457 if (!MO.getSubReg() || MI->readsVirtualRegister(Reg)) 4458 return 0; 4459 } else if (ARM::SPRRegClass.contains(Reg)) { 4460 // Physical register: MI must define the full D-reg. 4461 unsigned DReg = TRI->getMatchingSuperReg(Reg, ARM::ssub_0, 4462 &ARM::DPRRegClass); 4463 if (!DReg || !MI->definesRegister(DReg, TRI)) 4464 return 0; 4465 } 4466 4467 // MI has an unwanted D-register dependency. 4468 // Avoid defs in the previous N instructrions. 4469 return SwiftPartialUpdateClearance; 4470 } 4471 4472 // Break a partial register dependency after getPartialRegUpdateClearance 4473 // returned non-zero. 4474 void ARMBaseInstrInfo:: 4475 breakPartialRegDependency(MachineBasicBlock::iterator MI, 4476 unsigned OpNum, 4477 const TargetRegisterInfo *TRI) const { 4478 assert(MI && OpNum < MI->getDesc().getNumDefs() && "OpNum is not a def"); 4479 assert(TRI && "Need TRI instance"); 4480 4481 const MachineOperand &MO = MI->getOperand(OpNum); 4482 unsigned Reg = MO.getReg(); 4483 assert(TargetRegisterInfo::isPhysicalRegister(Reg) && 4484 "Can't break virtual register dependencies."); 4485 unsigned DReg = Reg; 4486 4487 // If MI defines an S-reg, find the corresponding D super-register. 4488 if (ARM::SPRRegClass.contains(Reg)) { 4489 DReg = ARM::D0 + (Reg - ARM::S0) / 2; 4490 assert(TRI->isSuperRegister(Reg, DReg) && "Register enums broken"); 4491 } 4492 4493 assert(ARM::DPRRegClass.contains(DReg) && "Can only break D-reg deps"); 4494 assert(MI->definesRegister(DReg, TRI) && "MI doesn't clobber full D-reg"); 4495 4496 // FIXME: In some cases, VLDRS can be changed to a VLD1DUPd32 which defines 4497 // the full D-register by loading the same value to both lanes. The 4498 // instruction is micro-coded with 2 uops, so don't do this until we can 4499 // properly schedule micro-coded instructions. The dispatcher stalls cause 4500 // too big regressions. 4501 4502 // Insert the dependency-breaking FCONSTD before MI. 4503 // 96 is the encoding of 0.5, but the actual value doesn't matter here. 4504 AddDefaultPred(BuildMI(*MI->getParent(), MI, MI->getDebugLoc(), 4505 get(ARM::FCONSTD), DReg).addImm(96)); 4506 MI->addRegisterKilled(DReg, TRI, true); 4507 } 4508 4509 bool ARMBaseInstrInfo::hasNOP() const { 4510 return (Subtarget.getFeatureBits() & ARM::HasV6T2Ops) != 0; 4511 } 4512 4513 bool ARMBaseInstrInfo::isSwiftFastImmShift(const MachineInstr *MI) const { 4514 if (MI->getNumOperands() < 4) 4515 return true; 4516 unsigned ShOpVal = MI->getOperand(3).getImm(); 4517 unsigned ShImm = ARM_AM::getSORegOffset(ShOpVal); 4518 // Swift supports faster shifts for: lsl 2, lsl 1, and lsr 1. 4519 if ((ShImm == 1 && ARM_AM::getSORegShOp(ShOpVal) == ARM_AM::lsr) || 4520 ((ShImm == 1 || ShImm == 2) && 4521 ARM_AM::getSORegShOp(ShOpVal) == ARM_AM::lsl)) 4522 return true; 4523 4524 return false; 4525 } 4526 4527 bool ARMBaseInstrInfo::getRegSequenceLikeInputs( 4528 const MachineInstr &MI, unsigned DefIdx, 4529 SmallVectorImpl<RegSubRegPairAndIdx> &InputRegs) const { 4530 assert(DefIdx < MI.getDesc().getNumDefs() && "Invalid definition index"); 4531 assert(MI.isRegSequenceLike() && "Invalid kind of instruction"); 4532 4533 switch (MI.getOpcode()) { 4534 case ARM::VMOVDRR: 4535 // dX = VMOVDRR rY, rZ 4536 // is the same as: 4537 // dX = REG_SEQUENCE rY, ssub_0, rZ, ssub_1 4538 // Populate the InputRegs accordingly. 4539 // rY 4540 const MachineOperand *MOReg = &MI.getOperand(1); 4541 InputRegs.push_back( 4542 RegSubRegPairAndIdx(MOReg->getReg(), MOReg->getSubReg(), ARM::ssub_0)); 4543 // rZ 4544 MOReg = &MI.getOperand(2); 4545 InputRegs.push_back( 4546 RegSubRegPairAndIdx(MOReg->getReg(), MOReg->getSubReg(), ARM::ssub_1)); 4547 return true; 4548 } 4549 llvm_unreachable("Target dependent opcode missing"); 4550 } 4551 4552 bool ARMBaseInstrInfo::getExtractSubregLikeInputs( 4553 const MachineInstr &MI, unsigned DefIdx, 4554 RegSubRegPairAndIdx &InputReg) const { 4555 assert(DefIdx < MI.getDesc().getNumDefs() && "Invalid definition index"); 4556 assert(MI.isExtractSubregLike() && "Invalid kind of instruction"); 4557 4558 switch (MI.getOpcode()) { 4559 case ARM::VMOVRRD: 4560 // rX, rY = VMOVRRD dZ 4561 // is the same as: 4562 // rX = EXTRACT_SUBREG dZ, ssub_0 4563 // rY = EXTRACT_SUBREG dZ, ssub_1 4564 const MachineOperand &MOReg = MI.getOperand(2); 4565 InputReg.Reg = MOReg.getReg(); 4566 InputReg.SubReg = MOReg.getSubReg(); 4567 InputReg.SubIdx = DefIdx == 0 ? ARM::ssub_0 : ARM::ssub_1; 4568 return true; 4569 } 4570 llvm_unreachable("Target dependent opcode missing"); 4571 } 4572 4573 bool ARMBaseInstrInfo::getInsertSubregLikeInputs( 4574 const MachineInstr &MI, unsigned DefIdx, RegSubRegPair &BaseReg, 4575 RegSubRegPairAndIdx &InsertedReg) const { 4576 assert(DefIdx < MI.getDesc().getNumDefs() && "Invalid definition index"); 4577 assert(MI.isInsertSubregLike() && "Invalid kind of instruction"); 4578 4579 switch (MI.getOpcode()) { 4580 case ARM::VSETLNi32: 4581 // dX = VSETLNi32 dY, rZ, imm 4582 const MachineOperand &MOBaseReg = MI.getOperand(1); 4583 const MachineOperand &MOInsertedReg = MI.getOperand(2); 4584 const MachineOperand &MOIndex = MI.getOperand(3); 4585 BaseReg.Reg = MOBaseReg.getReg(); 4586 BaseReg.SubReg = MOBaseReg.getSubReg(); 4587 4588 InsertedReg.Reg = MOInsertedReg.getReg(); 4589 InsertedReg.SubReg = MOInsertedReg.getSubReg(); 4590 InsertedReg.SubIdx = MOIndex.getImm() == 0 ? ARM::ssub_0 : ARM::ssub_1; 4591 return true; 4592 } 4593 llvm_unreachable("Target dependent opcode missing"); 4594 } 4595