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 "ARMBaseInstrInfo.h" 15 #include "ARM.h" 16 #include "ARMBaseRegisterInfo.h" 17 #include "ARMConstantPoolValue.h" 18 #include "ARMHazardRecognizer.h" 19 #include "ARMMachineFunctionInfo.h" 20 #include "MCTargetDesc/ARMAddressingModes.h" 21 #include "llvm/ADT/STLExtras.h" 22 #include "llvm/CodeGen/LiveVariables.h" 23 #include "llvm/CodeGen/MachineConstantPool.h" 24 #include "llvm/CodeGen/MachineFrameInfo.h" 25 #include "llvm/CodeGen/MachineInstrBuilder.h" 26 #include "llvm/CodeGen/MachineJumpTableInfo.h" 27 #include "llvm/CodeGen/MachineMemOperand.h" 28 #include "llvm/CodeGen/MachineRegisterInfo.h" 29 #include "llvm/CodeGen/SelectionDAGNodes.h" 30 #include "llvm/IR/Constants.h" 31 #include "llvm/IR/Function.h" 32 #include "llvm/IR/GlobalValue.h" 33 #include "llvm/MC/MCAsmInfo.h" 34 #include "llvm/Support/BranchProbability.h" 35 #include "llvm/Support/CommandLine.h" 36 #include "llvm/Support/Debug.h" 37 #include "llvm/Support/ErrorHandling.h" 38 39 #define GET_INSTRINFO_CTOR 40 #include "ARMGenInstrInfo.inc" 41 42 using namespace llvm; 43 44 static cl::opt<bool> 45 EnableARM3Addr("enable-arm-3-addr-conv", cl::Hidden, 46 cl::desc("Enable ARM 2-addr to 3-addr conv")); 47 48 static cl::opt<bool> 49 WidenVMOVS("widen-vmovs", cl::Hidden, cl::init(true), 50 cl::desc("Widen ARM vmovs to vmovd when possible")); 51 52 static cl::opt<unsigned> 53 SwiftPartialUpdateClearance("swift-partial-update-clearance", 54 cl::Hidden, cl::init(12), 55 cl::desc("Clearance before partial register updates")); 56 57 /// ARM_MLxEntry - Record information about MLA / MLS instructions. 58 struct ARM_MLxEntry { 59 uint16_t MLxOpc; // MLA / MLS opcode 60 uint16_t MulOpc; // Expanded multiplication opcode 61 uint16_t AddSubOpc; // Expanded add / sub opcode 62 bool NegAcc; // True if the acc is negated before the add / sub. 63 bool HasLane; // True if instruction has an extra "lane" operand. 64 }; 65 66 static const ARM_MLxEntry ARM_MLxTable[] = { 67 // MLxOpc, MulOpc, AddSubOpc, NegAcc, HasLane 68 // fp scalar ops 69 { ARM::VMLAS, ARM::VMULS, ARM::VADDS, false, false }, 70 { ARM::VMLSS, ARM::VMULS, ARM::VSUBS, false, false }, 71 { ARM::VMLAD, ARM::VMULD, ARM::VADDD, false, false }, 72 { ARM::VMLSD, ARM::VMULD, ARM::VSUBD, false, false }, 73 { ARM::VNMLAS, ARM::VNMULS, ARM::VSUBS, true, false }, 74 { ARM::VNMLSS, ARM::VMULS, ARM::VSUBS, true, false }, 75 { ARM::VNMLAD, ARM::VNMULD, ARM::VSUBD, true, false }, 76 { ARM::VNMLSD, ARM::VMULD, ARM::VSUBD, true, false }, 77 78 // fp SIMD ops 79 { ARM::VMLAfd, ARM::VMULfd, ARM::VADDfd, false, false }, 80 { ARM::VMLSfd, ARM::VMULfd, ARM::VSUBfd, false, false }, 81 { ARM::VMLAfq, ARM::VMULfq, ARM::VADDfq, false, false }, 82 { ARM::VMLSfq, ARM::VMULfq, ARM::VSUBfq, false, false }, 83 { ARM::VMLAslfd, ARM::VMULslfd, ARM::VADDfd, false, true }, 84 { ARM::VMLSslfd, ARM::VMULslfd, ARM::VSUBfd, false, true }, 85 { ARM::VMLAslfq, ARM::VMULslfq, ARM::VADDfq, false, true }, 86 { ARM::VMLSslfq, ARM::VMULslfq, ARM::VSUBfq, false, true }, 87 }; 88 89 ARMBaseInstrInfo::ARMBaseInstrInfo(const ARMSubtarget& STI) 90 : ARMGenInstrInfo(ARM::ADJCALLSTACKDOWN, ARM::ADJCALLSTACKUP), 91 Subtarget(STI) { 92 for (unsigned i = 0, e = array_lengthof(ARM_MLxTable); i != e; ++i) { 93 if (!MLxEntryMap.insert(std::make_pair(ARM_MLxTable[i].MLxOpc, i)).second) 94 assert(false && "Duplicated entries?"); 95 MLxHazardOpcodes.insert(ARM_MLxTable[i].AddSubOpc); 96 MLxHazardOpcodes.insert(ARM_MLxTable[i].MulOpc); 97 } 98 } 99 100 // Use a ScoreboardHazardRecognizer for prepass ARM scheduling. TargetInstrImpl 101 // currently defaults to no prepass hazard recognizer. 102 ScheduleHazardRecognizer *ARMBaseInstrInfo:: 103 CreateTargetHazardRecognizer(const TargetMachine *TM, 104 const ScheduleDAG *DAG) const { 105 if (usePreRAHazardRecognizer()) { 106 const InstrItineraryData *II = TM->getInstrItineraryData(); 107 return new ScoreboardHazardRecognizer(II, DAG, "pre-RA-sched"); 108 } 109 return TargetInstrInfo::CreateTargetHazardRecognizer(TM, DAG); 110 } 111 112 ScheduleHazardRecognizer *ARMBaseInstrInfo:: 113 CreateTargetPostRAHazardRecognizer(const InstrItineraryData *II, 114 const ScheduleDAG *DAG) const { 115 if (Subtarget.isThumb2() || Subtarget.hasVFP2()) 116 return (ScheduleHazardRecognizer *) 117 new ARMHazardRecognizer(II, *this, getRegisterInfo(), Subtarget, DAG); 118 return TargetInstrInfo::CreateTargetPostRAHazardRecognizer(II, DAG); 119 } 120 121 MachineInstr * 122 ARMBaseInstrInfo::convertToThreeAddress(MachineFunction::iterator &MFI, 123 MachineBasicBlock::iterator &MBBI, 124 LiveVariables *LV) const { 125 // FIXME: Thumb2 support. 126 127 if (!EnableARM3Addr) 128 return NULL; 129 130 MachineInstr *MI = MBBI; 131 MachineFunction &MF = *MI->getParent()->getParent(); 132 uint64_t TSFlags = MI->getDesc().TSFlags; 133 bool isPre = false; 134 switch ((TSFlags & ARMII::IndexModeMask) >> ARMII::IndexModeShift) { 135 default: return NULL; 136 case ARMII::IndexModePre: 137 isPre = true; 138 break; 139 case ARMII::IndexModePost: 140 break; 141 } 142 143 // Try splitting an indexed load/store to an un-indexed one plus an add/sub 144 // operation. 145 unsigned MemOpc = getUnindexedOpcode(MI->getOpcode()); 146 if (MemOpc == 0) 147 return NULL; 148 149 MachineInstr *UpdateMI = NULL; 150 MachineInstr *MemMI = NULL; 151 unsigned AddrMode = (TSFlags & ARMII::AddrModeMask); 152 const MCInstrDesc &MCID = MI->getDesc(); 153 unsigned NumOps = MCID.getNumOperands(); 154 bool isLoad = !MI->mayStore(); 155 const MachineOperand &WB = isLoad ? MI->getOperand(1) : MI->getOperand(0); 156 const MachineOperand &Base = MI->getOperand(2); 157 const MachineOperand &Offset = MI->getOperand(NumOps-3); 158 unsigned WBReg = WB.getReg(); 159 unsigned BaseReg = Base.getReg(); 160 unsigned OffReg = Offset.getReg(); 161 unsigned OffImm = MI->getOperand(NumOps-2).getImm(); 162 ARMCC::CondCodes Pred = (ARMCC::CondCodes)MI->getOperand(NumOps-1).getImm(); 163 switch (AddrMode) { 164 default: llvm_unreachable("Unknown indexed op!"); 165 case ARMII::AddrMode2: { 166 bool isSub = ARM_AM::getAM2Op(OffImm) == ARM_AM::sub; 167 unsigned Amt = ARM_AM::getAM2Offset(OffImm); 168 if (OffReg == 0) { 169 if (ARM_AM::getSOImmVal(Amt) == -1) 170 // Can't encode it in a so_imm operand. This transformation will 171 // add more than 1 instruction. Abandon! 172 return NULL; 173 UpdateMI = BuildMI(MF, MI->getDebugLoc(), 174 get(isSub ? ARM::SUBri : ARM::ADDri), WBReg) 175 .addReg(BaseReg).addImm(Amt) 176 .addImm(Pred).addReg(0).addReg(0); 177 } else if (Amt != 0) { 178 ARM_AM::ShiftOpc ShOpc = ARM_AM::getAM2ShiftOpc(OffImm); 179 unsigned SOOpc = ARM_AM::getSORegOpc(ShOpc, Amt); 180 UpdateMI = BuildMI(MF, MI->getDebugLoc(), 181 get(isSub ? ARM::SUBrsi : ARM::ADDrsi), WBReg) 182 .addReg(BaseReg).addReg(OffReg).addReg(0).addImm(SOOpc) 183 .addImm(Pred).addReg(0).addReg(0); 184 } else 185 UpdateMI = BuildMI(MF, MI->getDebugLoc(), 186 get(isSub ? ARM::SUBrr : ARM::ADDrr), WBReg) 187 .addReg(BaseReg).addReg(OffReg) 188 .addImm(Pred).addReg(0).addReg(0); 189 break; 190 } 191 case ARMII::AddrMode3 : { 192 bool isSub = ARM_AM::getAM3Op(OffImm) == ARM_AM::sub; 193 unsigned Amt = ARM_AM::getAM3Offset(OffImm); 194 if (OffReg == 0) 195 // Immediate is 8-bits. It's guaranteed to fit in a so_imm operand. 196 UpdateMI = BuildMI(MF, MI->getDebugLoc(), 197 get(isSub ? ARM::SUBri : ARM::ADDri), WBReg) 198 .addReg(BaseReg).addImm(Amt) 199 .addImm(Pred).addReg(0).addReg(0); 200 else 201 UpdateMI = BuildMI(MF, MI->getDebugLoc(), 202 get(isSub ? ARM::SUBrr : ARM::ADDrr), WBReg) 203 .addReg(BaseReg).addReg(OffReg) 204 .addImm(Pred).addReg(0).addReg(0); 205 break; 206 } 207 } 208 209 std::vector<MachineInstr*> NewMIs; 210 if (isPre) { 211 if (isLoad) 212 MemMI = BuildMI(MF, MI->getDebugLoc(), 213 get(MemOpc), MI->getOperand(0).getReg()) 214 .addReg(WBReg).addImm(0).addImm(Pred); 215 else 216 MemMI = BuildMI(MF, MI->getDebugLoc(), 217 get(MemOpc)).addReg(MI->getOperand(1).getReg()) 218 .addReg(WBReg).addReg(0).addImm(0).addImm(Pred); 219 NewMIs.push_back(MemMI); 220 NewMIs.push_back(UpdateMI); 221 } else { 222 if (isLoad) 223 MemMI = BuildMI(MF, MI->getDebugLoc(), 224 get(MemOpc), MI->getOperand(0).getReg()) 225 .addReg(BaseReg).addImm(0).addImm(Pred); 226 else 227 MemMI = BuildMI(MF, MI->getDebugLoc(), 228 get(MemOpc)).addReg(MI->getOperand(1).getReg()) 229 .addReg(BaseReg).addReg(0).addImm(0).addImm(Pred); 230 if (WB.isDead()) 231 UpdateMI->getOperand(0).setIsDead(); 232 NewMIs.push_back(UpdateMI); 233 NewMIs.push_back(MemMI); 234 } 235 236 // Transfer LiveVariables states, kill / dead info. 237 if (LV) { 238 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) { 239 MachineOperand &MO = MI->getOperand(i); 240 if (MO.isReg() && TargetRegisterInfo::isVirtualRegister(MO.getReg())) { 241 unsigned Reg = MO.getReg(); 242 243 LiveVariables::VarInfo &VI = LV->getVarInfo(Reg); 244 if (MO.isDef()) { 245 MachineInstr *NewMI = (Reg == WBReg) ? UpdateMI : MemMI; 246 if (MO.isDead()) 247 LV->addVirtualRegisterDead(Reg, NewMI); 248 } 249 if (MO.isUse() && MO.isKill()) { 250 for (unsigned j = 0; j < 2; ++j) { 251 // Look at the two new MI's in reverse order. 252 MachineInstr *NewMI = NewMIs[j]; 253 if (!NewMI->readsRegister(Reg)) 254 continue; 255 LV->addVirtualRegisterKilled(Reg, NewMI); 256 if (VI.removeKill(MI)) 257 VI.Kills.push_back(NewMI); 258 break; 259 } 260 } 261 } 262 } 263 } 264 265 MFI->insert(MBBI, NewMIs[1]); 266 MFI->insert(MBBI, NewMIs[0]); 267 return NewMIs[0]; 268 } 269 270 // Branch analysis. 271 bool 272 ARMBaseInstrInfo::AnalyzeBranch(MachineBasicBlock &MBB,MachineBasicBlock *&TBB, 273 MachineBasicBlock *&FBB, 274 SmallVectorImpl<MachineOperand> &Cond, 275 bool AllowModify) const { 276 // If the block has no terminators, it just falls into the block after it. 277 MachineBasicBlock::iterator I = MBB.end(); 278 if (I == MBB.begin()) 279 return false; 280 --I; 281 while (I->isDebugValue()) { 282 if (I == MBB.begin()) 283 return false; 284 --I; 285 } 286 if (!isUnpredicatedTerminator(I)) 287 return false; 288 289 // Get the last instruction in the block. 290 MachineInstr *LastInst = I; 291 292 // If there is only one terminator instruction, process it. 293 unsigned LastOpc = LastInst->getOpcode(); 294 if (I == MBB.begin() || !isUnpredicatedTerminator(--I)) { 295 if (isUncondBranchOpcode(LastOpc)) { 296 TBB = LastInst->getOperand(0).getMBB(); 297 return false; 298 } 299 if (isCondBranchOpcode(LastOpc)) { 300 // Block ends with fall-through condbranch. 301 TBB = LastInst->getOperand(0).getMBB(); 302 Cond.push_back(LastInst->getOperand(1)); 303 Cond.push_back(LastInst->getOperand(2)); 304 return false; 305 } 306 return true; // Can't handle indirect branch. 307 } 308 309 // Get the instruction before it if it is a terminator. 310 MachineInstr *SecondLastInst = I; 311 unsigned SecondLastOpc = SecondLastInst->getOpcode(); 312 313 // If AllowModify is true and the block ends with two or more unconditional 314 // branches, delete all but the first unconditional branch. 315 if (AllowModify && isUncondBranchOpcode(LastOpc)) { 316 while (isUncondBranchOpcode(SecondLastOpc)) { 317 LastInst->eraseFromParent(); 318 LastInst = SecondLastInst; 319 LastOpc = LastInst->getOpcode(); 320 if (I == MBB.begin() || !isUnpredicatedTerminator(--I)) { 321 // Return now the only terminator is an unconditional branch. 322 TBB = LastInst->getOperand(0).getMBB(); 323 return false; 324 } else { 325 SecondLastInst = I; 326 SecondLastOpc = SecondLastInst->getOpcode(); 327 } 328 } 329 } 330 331 // If there are three terminators, we don't know what sort of block this is. 332 if (SecondLastInst && I != MBB.begin() && isUnpredicatedTerminator(--I)) 333 return true; 334 335 // If the block ends with a B and a Bcc, handle it. 336 if (isCondBranchOpcode(SecondLastOpc) && isUncondBranchOpcode(LastOpc)) { 337 TBB = SecondLastInst->getOperand(0).getMBB(); 338 Cond.push_back(SecondLastInst->getOperand(1)); 339 Cond.push_back(SecondLastInst->getOperand(2)); 340 FBB = LastInst->getOperand(0).getMBB(); 341 return false; 342 } 343 344 // If the block ends with two unconditional branches, handle it. The second 345 // one is not executed, so remove it. 346 if (isUncondBranchOpcode(SecondLastOpc) && isUncondBranchOpcode(LastOpc)) { 347 TBB = SecondLastInst->getOperand(0).getMBB(); 348 I = LastInst; 349 if (AllowModify) 350 I->eraseFromParent(); 351 return false; 352 } 353 354 // ...likewise if it ends with a branch table followed by an unconditional 355 // branch. The branch folder can create these, and we must get rid of them for 356 // correctness of Thumb constant islands. 357 if ((isJumpTableBranchOpcode(SecondLastOpc) || 358 isIndirectBranchOpcode(SecondLastOpc)) && 359 isUncondBranchOpcode(LastOpc)) { 360 I = LastInst; 361 if (AllowModify) 362 I->eraseFromParent(); 363 return true; 364 } 365 366 // Otherwise, can't handle this. 367 return true; 368 } 369 370 371 unsigned ARMBaseInstrInfo::RemoveBranch(MachineBasicBlock &MBB) const { 372 MachineBasicBlock::iterator I = MBB.end(); 373 if (I == MBB.begin()) return 0; 374 --I; 375 while (I->isDebugValue()) { 376 if (I == MBB.begin()) 377 return 0; 378 --I; 379 } 380 if (!isUncondBranchOpcode(I->getOpcode()) && 381 !isCondBranchOpcode(I->getOpcode())) 382 return 0; 383 384 // Remove the branch. 385 I->eraseFromParent(); 386 387 I = MBB.end(); 388 389 if (I == MBB.begin()) return 1; 390 --I; 391 if (!isCondBranchOpcode(I->getOpcode())) 392 return 1; 393 394 // Remove the branch. 395 I->eraseFromParent(); 396 return 2; 397 } 398 399 unsigned 400 ARMBaseInstrInfo::InsertBranch(MachineBasicBlock &MBB, MachineBasicBlock *TBB, 401 MachineBasicBlock *FBB, 402 const SmallVectorImpl<MachineOperand> &Cond, 403 DebugLoc DL) const { 404 ARMFunctionInfo *AFI = MBB.getParent()->getInfo<ARMFunctionInfo>(); 405 int BOpc = !AFI->isThumbFunction() 406 ? ARM::B : (AFI->isThumb2Function() ? ARM::t2B : ARM::tB); 407 int BccOpc = !AFI->isThumbFunction() 408 ? ARM::Bcc : (AFI->isThumb2Function() ? ARM::t2Bcc : ARM::tBcc); 409 bool isThumb = AFI->isThumbFunction() || AFI->isThumb2Function(); 410 411 // Shouldn't be a fall through. 412 assert(TBB && "InsertBranch must not be told to insert a fallthrough"); 413 assert((Cond.size() == 2 || Cond.size() == 0) && 414 "ARM branch conditions have two components!"); 415 416 if (FBB == 0) { 417 if (Cond.empty()) { // Unconditional branch? 418 if (isThumb) 419 BuildMI(&MBB, DL, get(BOpc)).addMBB(TBB).addImm(ARMCC::AL).addReg(0); 420 else 421 BuildMI(&MBB, DL, get(BOpc)).addMBB(TBB); 422 } else 423 BuildMI(&MBB, DL, get(BccOpc)).addMBB(TBB) 424 .addImm(Cond[0].getImm()).addReg(Cond[1].getReg()); 425 return 1; 426 } 427 428 // Two-way conditional branch. 429 BuildMI(&MBB, DL, get(BccOpc)).addMBB(TBB) 430 .addImm(Cond[0].getImm()).addReg(Cond[1].getReg()); 431 if (isThumb) 432 BuildMI(&MBB, DL, get(BOpc)).addMBB(FBB).addImm(ARMCC::AL).addReg(0); 433 else 434 BuildMI(&MBB, DL, get(BOpc)).addMBB(FBB); 435 return 2; 436 } 437 438 bool ARMBaseInstrInfo:: 439 ReverseBranchCondition(SmallVectorImpl<MachineOperand> &Cond) const { 440 ARMCC::CondCodes CC = (ARMCC::CondCodes)(int)Cond[0].getImm(); 441 Cond[0].setImm(ARMCC::getOppositeCondition(CC)); 442 return false; 443 } 444 445 bool ARMBaseInstrInfo::isPredicated(const MachineInstr *MI) const { 446 if (MI->isBundle()) { 447 MachineBasicBlock::const_instr_iterator I = MI; 448 MachineBasicBlock::const_instr_iterator E = MI->getParent()->instr_end(); 449 while (++I != E && I->isInsideBundle()) { 450 int PIdx = I->findFirstPredOperandIdx(); 451 if (PIdx != -1 && I->getOperand(PIdx).getImm() != ARMCC::AL) 452 return true; 453 } 454 return false; 455 } 456 457 int PIdx = MI->findFirstPredOperandIdx(); 458 return PIdx != -1 && MI->getOperand(PIdx).getImm() != ARMCC::AL; 459 } 460 461 bool ARMBaseInstrInfo:: 462 PredicateInstruction(MachineInstr *MI, 463 const SmallVectorImpl<MachineOperand> &Pred) const { 464 unsigned Opc = MI->getOpcode(); 465 if (isUncondBranchOpcode(Opc)) { 466 MI->setDesc(get(getMatchingCondBranchOpcode(Opc))); 467 MachineInstrBuilder(*MI->getParent()->getParent(), MI) 468 .addImm(Pred[0].getImm()) 469 .addReg(Pred[1].getReg()); 470 return true; 471 } 472 473 int PIdx = MI->findFirstPredOperandIdx(); 474 if (PIdx != -1) { 475 MachineOperand &PMO = MI->getOperand(PIdx); 476 PMO.setImm(Pred[0].getImm()); 477 MI->getOperand(PIdx+1).setReg(Pred[1].getReg()); 478 return true; 479 } 480 return false; 481 } 482 483 bool ARMBaseInstrInfo:: 484 SubsumesPredicate(const SmallVectorImpl<MachineOperand> &Pred1, 485 const SmallVectorImpl<MachineOperand> &Pred2) const { 486 if (Pred1.size() > 2 || Pred2.size() > 2) 487 return false; 488 489 ARMCC::CondCodes CC1 = (ARMCC::CondCodes)Pred1[0].getImm(); 490 ARMCC::CondCodes CC2 = (ARMCC::CondCodes)Pred2[0].getImm(); 491 if (CC1 == CC2) 492 return true; 493 494 switch (CC1) { 495 default: 496 return false; 497 case ARMCC::AL: 498 return true; 499 case ARMCC::HS: 500 return CC2 == ARMCC::HI; 501 case ARMCC::LS: 502 return CC2 == ARMCC::LO || CC2 == ARMCC::EQ; 503 case ARMCC::GE: 504 return CC2 == ARMCC::GT; 505 case ARMCC::LE: 506 return CC2 == ARMCC::LT; 507 } 508 } 509 510 bool ARMBaseInstrInfo::DefinesPredicate(MachineInstr *MI, 511 std::vector<MachineOperand> &Pred) const { 512 bool Found = false; 513 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) { 514 const MachineOperand &MO = MI->getOperand(i); 515 if ((MO.isRegMask() && MO.clobbersPhysReg(ARM::CPSR)) || 516 (MO.isReg() && MO.isDef() && MO.getReg() == ARM::CPSR)) { 517 Pred.push_back(MO); 518 Found = true; 519 } 520 } 521 522 return Found; 523 } 524 525 /// isPredicable - Return true if the specified instruction can be predicated. 526 /// By default, this returns true for every instruction with a 527 /// PredicateOperand. 528 bool ARMBaseInstrInfo::isPredicable(MachineInstr *MI) const { 529 if (!MI->isPredicable()) 530 return false; 531 532 if ((MI->getDesc().TSFlags & ARMII::DomainMask) == ARMII::DomainNEON) { 533 ARMFunctionInfo *AFI = 534 MI->getParent()->getParent()->getInfo<ARMFunctionInfo>(); 535 return AFI->isThumb2Function(); 536 } 537 return true; 538 } 539 540 /// FIXME: Works around a gcc miscompilation with -fstrict-aliasing. 541 LLVM_ATTRIBUTE_NOINLINE 542 static unsigned getNumJTEntries(const std::vector<MachineJumpTableEntry> &JT, 543 unsigned JTI); 544 static unsigned getNumJTEntries(const std::vector<MachineJumpTableEntry> &JT, 545 unsigned JTI) { 546 assert(JTI < JT.size()); 547 return JT[JTI].MBBs.size(); 548 } 549 550 /// GetInstSize - Return the size of the specified MachineInstr. 551 /// 552 unsigned ARMBaseInstrInfo::GetInstSizeInBytes(const MachineInstr *MI) const { 553 const MachineBasicBlock &MBB = *MI->getParent(); 554 const MachineFunction *MF = MBB.getParent(); 555 const MCAsmInfo *MAI = MF->getTarget().getMCAsmInfo(); 556 557 const MCInstrDesc &MCID = MI->getDesc(); 558 if (MCID.getSize()) 559 return MCID.getSize(); 560 561 // If this machine instr is an inline asm, measure it. 562 if (MI->getOpcode() == ARM::INLINEASM) 563 return getInlineAsmLength(MI->getOperand(0).getSymbolName(), *MAI); 564 if (MI->isLabel()) 565 return 0; 566 unsigned Opc = MI->getOpcode(); 567 switch (Opc) { 568 case TargetOpcode::IMPLICIT_DEF: 569 case TargetOpcode::KILL: 570 case TargetOpcode::PROLOG_LABEL: 571 case TargetOpcode::EH_LABEL: 572 case TargetOpcode::DBG_VALUE: 573 return 0; 574 case TargetOpcode::BUNDLE: 575 return getInstBundleLength(MI); 576 case ARM::MOVi16_ga_pcrel: 577 case ARM::MOVTi16_ga_pcrel: 578 case ARM::t2MOVi16_ga_pcrel: 579 case ARM::t2MOVTi16_ga_pcrel: 580 return 4; 581 case ARM::MOVi32imm: 582 case ARM::t2MOVi32imm: 583 return 8; 584 case ARM::CONSTPOOL_ENTRY: 585 // If this machine instr is a constant pool entry, its size is recorded as 586 // operand #2. 587 return MI->getOperand(2).getImm(); 588 case ARM::Int_eh_sjlj_longjmp: 589 return 16; 590 case ARM::tInt_eh_sjlj_longjmp: 591 return 10; 592 case ARM::Int_eh_sjlj_setjmp: 593 case ARM::Int_eh_sjlj_setjmp_nofp: 594 return 20; 595 case ARM::tInt_eh_sjlj_setjmp: 596 case ARM::t2Int_eh_sjlj_setjmp: 597 case ARM::t2Int_eh_sjlj_setjmp_nofp: 598 return 12; 599 case ARM::BR_JTr: 600 case ARM::BR_JTm: 601 case ARM::BR_JTadd: 602 case ARM::tBR_JTr: 603 case ARM::t2BR_JT: 604 case ARM::t2TBB_JT: 605 case ARM::t2TBH_JT: { 606 // These are jumptable branches, i.e. a branch followed by an inlined 607 // jumptable. The size is 4 + 4 * number of entries. For TBB, each 608 // entry is one byte; TBH two byte each. 609 unsigned EntrySize = (Opc == ARM::t2TBB_JT) 610 ? 1 : ((Opc == ARM::t2TBH_JT) ? 2 : 4); 611 unsigned NumOps = MCID.getNumOperands(); 612 MachineOperand JTOP = 613 MI->getOperand(NumOps - (MI->isPredicable() ? 3 : 2)); 614 unsigned JTI = JTOP.getIndex(); 615 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo(); 616 assert(MJTI != 0); 617 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables(); 618 assert(JTI < JT.size()); 619 // Thumb instructions are 2 byte aligned, but JT entries are 4 byte 620 // 4 aligned. The assembler / linker may add 2 byte padding just before 621 // the JT entries. The size does not include this padding; the 622 // constant islands pass does separate bookkeeping for it. 623 // FIXME: If we know the size of the function is less than (1 << 16) *2 624 // bytes, we can use 16-bit entries instead. Then there won't be an 625 // alignment issue. 626 unsigned InstSize = (Opc == ARM::tBR_JTr || Opc == ARM::t2BR_JT) ? 2 : 4; 627 unsigned NumEntries = getNumJTEntries(JT, JTI); 628 if (Opc == ARM::t2TBB_JT && (NumEntries & 1)) 629 // Make sure the instruction that follows TBB is 2-byte aligned. 630 // FIXME: Constant island pass should insert an "ALIGN" instruction 631 // instead. 632 ++NumEntries; 633 return NumEntries * EntrySize + InstSize; 634 } 635 default: 636 // Otherwise, pseudo-instruction sizes are zero. 637 return 0; 638 } 639 } 640 641 unsigned ARMBaseInstrInfo::getInstBundleLength(const MachineInstr *MI) const { 642 unsigned Size = 0; 643 MachineBasicBlock::const_instr_iterator I = MI; 644 MachineBasicBlock::const_instr_iterator E = MI->getParent()->instr_end(); 645 while (++I != E && I->isInsideBundle()) { 646 assert(!I->isBundle() && "No nested bundle!"); 647 Size += GetInstSizeInBytes(&*I); 648 } 649 return Size; 650 } 651 652 void ARMBaseInstrInfo::copyPhysReg(MachineBasicBlock &MBB, 653 MachineBasicBlock::iterator I, DebugLoc DL, 654 unsigned DestReg, unsigned SrcReg, 655 bool KillSrc) const { 656 bool GPRDest = ARM::GPRRegClass.contains(DestReg); 657 bool GPRSrc = ARM::GPRRegClass.contains(SrcReg); 658 659 if (GPRDest && GPRSrc) { 660 AddDefaultCC(AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::MOVr), DestReg) 661 .addReg(SrcReg, getKillRegState(KillSrc)))); 662 return; 663 } 664 665 bool SPRDest = ARM::SPRRegClass.contains(DestReg); 666 bool SPRSrc = ARM::SPRRegClass.contains(SrcReg); 667 668 unsigned Opc = 0; 669 if (SPRDest && SPRSrc) 670 Opc = ARM::VMOVS; 671 else if (GPRDest && SPRSrc) 672 Opc = ARM::VMOVRS; 673 else if (SPRDest && GPRSrc) 674 Opc = ARM::VMOVSR; 675 else if (ARM::DPRRegClass.contains(DestReg, SrcReg)) 676 Opc = ARM::VMOVD; 677 else if (ARM::QPRRegClass.contains(DestReg, SrcReg)) 678 Opc = ARM::VORRq; 679 680 if (Opc) { 681 MachineInstrBuilder MIB = BuildMI(MBB, I, DL, get(Opc), DestReg); 682 MIB.addReg(SrcReg, getKillRegState(KillSrc)); 683 if (Opc == ARM::VORRq) 684 MIB.addReg(SrcReg, getKillRegState(KillSrc)); 685 AddDefaultPred(MIB); 686 return; 687 } 688 689 // Handle register classes that require multiple instructions. 690 unsigned BeginIdx = 0; 691 unsigned SubRegs = 0; 692 int Spacing = 1; 693 694 // Use VORRq when possible. 695 if (ARM::QQPRRegClass.contains(DestReg, SrcReg)) 696 Opc = ARM::VORRq, BeginIdx = ARM::qsub_0, SubRegs = 2; 697 else if (ARM::QQQQPRRegClass.contains(DestReg, SrcReg)) 698 Opc = ARM::VORRq, BeginIdx = ARM::qsub_0, SubRegs = 4; 699 // Fall back to VMOVD. 700 else if (ARM::DPairRegClass.contains(DestReg, SrcReg)) 701 Opc = ARM::VMOVD, BeginIdx = ARM::dsub_0, SubRegs = 2; 702 else if (ARM::DTripleRegClass.contains(DestReg, SrcReg)) 703 Opc = ARM::VMOVD, BeginIdx = ARM::dsub_0, SubRegs = 3; 704 else if (ARM::DQuadRegClass.contains(DestReg, SrcReg)) 705 Opc = ARM::VMOVD, BeginIdx = ARM::dsub_0, SubRegs = 4; 706 else if (ARM::GPRPairRegClass.contains(DestReg, SrcReg)) 707 Opc = ARM::MOVr, BeginIdx = ARM::gsub_0, SubRegs = 2; 708 709 else if (ARM::DPairSpcRegClass.contains(DestReg, SrcReg)) 710 Opc = ARM::VMOVD, BeginIdx = ARM::dsub_0, SubRegs = 2, Spacing = 2; 711 else if (ARM::DTripleSpcRegClass.contains(DestReg, SrcReg)) 712 Opc = ARM::VMOVD, BeginIdx = ARM::dsub_0, SubRegs = 3, Spacing = 2; 713 else if (ARM::DQuadSpcRegClass.contains(DestReg, SrcReg)) 714 Opc = ARM::VMOVD, BeginIdx = ARM::dsub_0, SubRegs = 4, Spacing = 2; 715 716 assert(Opc && "Impossible reg-to-reg copy"); 717 718 const TargetRegisterInfo *TRI = &getRegisterInfo(); 719 MachineInstrBuilder Mov; 720 721 // Copy register tuples backward when the first Dest reg overlaps with SrcReg. 722 if (TRI->regsOverlap(SrcReg, TRI->getSubReg(DestReg, BeginIdx))) { 723 BeginIdx = BeginIdx + ((SubRegs-1)*Spacing); 724 Spacing = -Spacing; 725 } 726 #ifndef NDEBUG 727 SmallSet<unsigned, 4> DstRegs; 728 #endif 729 for (unsigned i = 0; i != SubRegs; ++i) { 730 unsigned Dst = TRI->getSubReg(DestReg, BeginIdx + i*Spacing); 731 unsigned Src = TRI->getSubReg(SrcReg, BeginIdx + i*Spacing); 732 assert(Dst && Src && "Bad sub-register"); 733 #ifndef NDEBUG 734 assert(!DstRegs.count(Src) && "destructive vector copy"); 735 DstRegs.insert(Dst); 736 #endif 737 Mov = BuildMI(MBB, I, I->getDebugLoc(), get(Opc), Dst) 738 .addReg(Src); 739 // VORR takes two source operands. 740 if (Opc == ARM::VORRq) 741 Mov.addReg(Src); 742 Mov = AddDefaultPred(Mov); 743 } 744 // Add implicit super-register defs and kills to the last instruction. 745 Mov->addRegisterDefined(DestReg, TRI); 746 if (KillSrc) 747 Mov->addRegisterKilled(SrcReg, TRI); 748 } 749 750 static const 751 MachineInstrBuilder &AddDReg(MachineInstrBuilder &MIB, 752 unsigned Reg, unsigned SubIdx, unsigned State, 753 const TargetRegisterInfo *TRI) { 754 if (!SubIdx) 755 return MIB.addReg(Reg, State); 756 757 if (TargetRegisterInfo::isPhysicalRegister(Reg)) 758 return MIB.addReg(TRI->getSubReg(Reg, SubIdx), State); 759 return MIB.addReg(Reg, State, SubIdx); 760 } 761 762 void ARMBaseInstrInfo:: 763 storeRegToStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I, 764 unsigned SrcReg, bool isKill, int FI, 765 const TargetRegisterClass *RC, 766 const TargetRegisterInfo *TRI) const { 767 DebugLoc DL; 768 if (I != MBB.end()) DL = I->getDebugLoc(); 769 MachineFunction &MF = *MBB.getParent(); 770 MachineFrameInfo &MFI = *MF.getFrameInfo(); 771 unsigned Align = MFI.getObjectAlignment(FI); 772 773 MachineMemOperand *MMO = 774 MF.getMachineMemOperand(MachinePointerInfo::getFixedStack(FI), 775 MachineMemOperand::MOStore, 776 MFI.getObjectSize(FI), 777 Align); 778 779 switch (RC->getSize()) { 780 case 4: 781 if (ARM::GPRRegClass.hasSubClassEq(RC)) { 782 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::STRi12)) 783 .addReg(SrcReg, getKillRegState(isKill)) 784 .addFrameIndex(FI).addImm(0).addMemOperand(MMO)); 785 } else if (ARM::SPRRegClass.hasSubClassEq(RC)) { 786 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTRS)) 787 .addReg(SrcReg, getKillRegState(isKill)) 788 .addFrameIndex(FI).addImm(0).addMemOperand(MMO)); 789 } else 790 llvm_unreachable("Unknown reg class!"); 791 break; 792 case 8: 793 if (ARM::DPRRegClass.hasSubClassEq(RC)) { 794 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTRD)) 795 .addReg(SrcReg, getKillRegState(isKill)) 796 .addFrameIndex(FI).addImm(0).addMemOperand(MMO)); 797 } else if (ARM::GPRPairRegClass.hasSubClassEq(RC)) { 798 MachineInstrBuilder MIB = 799 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::STMIA)) 800 .addFrameIndex(FI)) 801 .addMemOperand(MMO); 802 MIB = AddDReg(MIB, SrcReg, ARM::gsub_0, getKillRegState(isKill), TRI); 803 AddDReg(MIB, SrcReg, ARM::gsub_1, 0, TRI); 804 } else 805 llvm_unreachable("Unknown reg class!"); 806 break; 807 case 16: 808 if (ARM::DPairRegClass.hasSubClassEq(RC)) { 809 // Use aligned spills if the stack can be realigned. 810 if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) { 811 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VST1q64)) 812 .addFrameIndex(FI).addImm(16) 813 .addReg(SrcReg, getKillRegState(isKill)) 814 .addMemOperand(MMO)); 815 } else { 816 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTMQIA)) 817 .addReg(SrcReg, getKillRegState(isKill)) 818 .addFrameIndex(FI) 819 .addMemOperand(MMO)); 820 } 821 } else 822 llvm_unreachable("Unknown reg class!"); 823 break; 824 case 24: 825 if (ARM::DTripleRegClass.hasSubClassEq(RC)) { 826 // Use aligned spills if the stack can be realigned. 827 if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) { 828 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VST1d64TPseudo)) 829 .addFrameIndex(FI).addImm(16) 830 .addReg(SrcReg, getKillRegState(isKill)) 831 .addMemOperand(MMO)); 832 } else { 833 MachineInstrBuilder MIB = 834 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTMDIA)) 835 .addFrameIndex(FI)) 836 .addMemOperand(MMO); 837 MIB = AddDReg(MIB, SrcReg, ARM::dsub_0, getKillRegState(isKill), TRI); 838 MIB = AddDReg(MIB, SrcReg, ARM::dsub_1, 0, TRI); 839 AddDReg(MIB, SrcReg, ARM::dsub_2, 0, TRI); 840 } 841 } else 842 llvm_unreachable("Unknown reg class!"); 843 break; 844 case 32: 845 if (ARM::QQPRRegClass.hasSubClassEq(RC) || ARM::DQuadRegClass.hasSubClassEq(RC)) { 846 if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) { 847 // FIXME: It's possible to only store part of the QQ register if the 848 // spilled def has a sub-register index. 849 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VST1d64QPseudo)) 850 .addFrameIndex(FI).addImm(16) 851 .addReg(SrcReg, getKillRegState(isKill)) 852 .addMemOperand(MMO)); 853 } else { 854 MachineInstrBuilder MIB = 855 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTMDIA)) 856 .addFrameIndex(FI)) 857 .addMemOperand(MMO); 858 MIB = AddDReg(MIB, SrcReg, ARM::dsub_0, getKillRegState(isKill), TRI); 859 MIB = AddDReg(MIB, SrcReg, ARM::dsub_1, 0, TRI); 860 MIB = AddDReg(MIB, SrcReg, ARM::dsub_2, 0, TRI); 861 AddDReg(MIB, SrcReg, ARM::dsub_3, 0, TRI); 862 } 863 } else 864 llvm_unreachable("Unknown reg class!"); 865 break; 866 case 64: 867 if (ARM::QQQQPRRegClass.hasSubClassEq(RC)) { 868 MachineInstrBuilder MIB = 869 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VSTMDIA)) 870 .addFrameIndex(FI)) 871 .addMemOperand(MMO); 872 MIB = AddDReg(MIB, SrcReg, ARM::dsub_0, getKillRegState(isKill), TRI); 873 MIB = AddDReg(MIB, SrcReg, ARM::dsub_1, 0, TRI); 874 MIB = AddDReg(MIB, SrcReg, ARM::dsub_2, 0, TRI); 875 MIB = AddDReg(MIB, SrcReg, ARM::dsub_3, 0, TRI); 876 MIB = AddDReg(MIB, SrcReg, ARM::dsub_4, 0, TRI); 877 MIB = AddDReg(MIB, SrcReg, ARM::dsub_5, 0, TRI); 878 MIB = AddDReg(MIB, SrcReg, ARM::dsub_6, 0, TRI); 879 AddDReg(MIB, SrcReg, ARM::dsub_7, 0, TRI); 880 } else 881 llvm_unreachable("Unknown reg class!"); 882 break; 883 default: 884 llvm_unreachable("Unknown reg class!"); 885 } 886 } 887 888 unsigned 889 ARMBaseInstrInfo::isStoreToStackSlot(const MachineInstr *MI, 890 int &FrameIndex) const { 891 switch (MI->getOpcode()) { 892 default: break; 893 case ARM::STRrs: 894 case ARM::t2STRs: // FIXME: don't use t2STRs to access frame. 895 if (MI->getOperand(1).isFI() && 896 MI->getOperand(2).isReg() && 897 MI->getOperand(3).isImm() && 898 MI->getOperand(2).getReg() == 0 && 899 MI->getOperand(3).getImm() == 0) { 900 FrameIndex = MI->getOperand(1).getIndex(); 901 return MI->getOperand(0).getReg(); 902 } 903 break; 904 case ARM::STRi12: 905 case ARM::t2STRi12: 906 case ARM::tSTRspi: 907 case ARM::VSTRD: 908 case ARM::VSTRS: 909 if (MI->getOperand(1).isFI() && 910 MI->getOperand(2).isImm() && 911 MI->getOperand(2).getImm() == 0) { 912 FrameIndex = MI->getOperand(1).getIndex(); 913 return MI->getOperand(0).getReg(); 914 } 915 break; 916 case ARM::VST1q64: 917 case ARM::VST1d64TPseudo: 918 case ARM::VST1d64QPseudo: 919 if (MI->getOperand(0).isFI() && 920 MI->getOperand(2).getSubReg() == 0) { 921 FrameIndex = MI->getOperand(0).getIndex(); 922 return MI->getOperand(2).getReg(); 923 } 924 break; 925 case ARM::VSTMQIA: 926 if (MI->getOperand(1).isFI() && 927 MI->getOperand(0).getSubReg() == 0) { 928 FrameIndex = MI->getOperand(1).getIndex(); 929 return MI->getOperand(0).getReg(); 930 } 931 break; 932 } 933 934 return 0; 935 } 936 937 unsigned ARMBaseInstrInfo::isStoreToStackSlotPostFE(const MachineInstr *MI, 938 int &FrameIndex) const { 939 const MachineMemOperand *Dummy; 940 return MI->mayStore() && hasStoreToStackSlot(MI, Dummy, FrameIndex); 941 } 942 943 void ARMBaseInstrInfo:: 944 loadRegFromStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I, 945 unsigned DestReg, int FI, 946 const TargetRegisterClass *RC, 947 const TargetRegisterInfo *TRI) const { 948 DebugLoc DL; 949 if (I != MBB.end()) DL = I->getDebugLoc(); 950 MachineFunction &MF = *MBB.getParent(); 951 ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>(); 952 MachineFrameInfo &MFI = *MF.getFrameInfo(); 953 unsigned Align = MFI.getObjectAlignment(FI); 954 MachineMemOperand *MMO = 955 MF.getMachineMemOperand( 956 MachinePointerInfo::getFixedStack(FI), 957 MachineMemOperand::MOLoad, 958 MFI.getObjectSize(FI), 959 Align); 960 961 switch (RC->getSize()) { 962 case 4: 963 if (ARM::GPRRegClass.hasSubClassEq(RC)) { 964 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::LDRi12), DestReg) 965 .addFrameIndex(FI).addImm(0).addMemOperand(MMO)); 966 967 } else if (ARM::SPRRegClass.hasSubClassEq(RC)) { 968 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDRS), DestReg) 969 .addFrameIndex(FI).addImm(0).addMemOperand(MMO)); 970 } else 971 llvm_unreachable("Unknown reg class!"); 972 break; 973 case 8: 974 if (ARM::DPRRegClass.hasSubClassEq(RC)) { 975 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDRD), DestReg) 976 .addFrameIndex(FI).addImm(0).addMemOperand(MMO)); 977 } else if (ARM::GPRPairRegClass.hasSubClassEq(RC)) { 978 unsigned LdmOpc = AFI->isThumbFunction() ? ARM::t2LDMIA : ARM::LDMIA; 979 MachineInstrBuilder MIB = 980 AddDefaultPred(BuildMI(MBB, I, DL, get(LdmOpc)) 981 .addFrameIndex(FI).addImm(0).addMemOperand(MMO)); 982 MIB = AddDReg(MIB, DestReg, ARM::gsub_0, RegState::DefineNoRead, TRI); 983 MIB = AddDReg(MIB, DestReg, ARM::gsub_1, RegState::DefineNoRead, TRI); 984 if (TargetRegisterInfo::isPhysicalRegister(DestReg)) 985 MIB.addReg(DestReg, RegState::ImplicitDefine); 986 } else 987 llvm_unreachable("Unknown reg class!"); 988 break; 989 case 16: 990 if (ARM::DPairRegClass.hasSubClassEq(RC)) { 991 if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) { 992 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLD1q64), DestReg) 993 .addFrameIndex(FI).addImm(16) 994 .addMemOperand(MMO)); 995 } else { 996 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDMQIA), DestReg) 997 .addFrameIndex(FI) 998 .addMemOperand(MMO)); 999 } 1000 } else 1001 llvm_unreachable("Unknown reg class!"); 1002 break; 1003 case 24: 1004 if (ARM::DTripleRegClass.hasSubClassEq(RC)) { 1005 if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) { 1006 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLD1d64TPseudo), DestReg) 1007 .addFrameIndex(FI).addImm(16) 1008 .addMemOperand(MMO)); 1009 } else { 1010 MachineInstrBuilder MIB = 1011 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDMDIA)) 1012 .addFrameIndex(FI) 1013 .addMemOperand(MMO)); 1014 MIB = AddDReg(MIB, DestReg, ARM::dsub_0, RegState::DefineNoRead, TRI); 1015 MIB = AddDReg(MIB, DestReg, ARM::dsub_1, RegState::DefineNoRead, TRI); 1016 MIB = AddDReg(MIB, DestReg, ARM::dsub_2, RegState::DefineNoRead, TRI); 1017 if (TargetRegisterInfo::isPhysicalRegister(DestReg)) 1018 MIB.addReg(DestReg, RegState::ImplicitDefine); 1019 } 1020 } else 1021 llvm_unreachable("Unknown reg class!"); 1022 break; 1023 case 32: 1024 if (ARM::QQPRRegClass.hasSubClassEq(RC) || ARM::DQuadRegClass.hasSubClassEq(RC)) { 1025 if (Align >= 16 && getRegisterInfo().canRealignStack(MF)) { 1026 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLD1d64QPseudo), DestReg) 1027 .addFrameIndex(FI).addImm(16) 1028 .addMemOperand(MMO)); 1029 } else { 1030 MachineInstrBuilder MIB = 1031 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDMDIA)) 1032 .addFrameIndex(FI)) 1033 .addMemOperand(MMO); 1034 MIB = AddDReg(MIB, DestReg, ARM::dsub_0, RegState::DefineNoRead, TRI); 1035 MIB = AddDReg(MIB, DestReg, ARM::dsub_1, RegState::DefineNoRead, TRI); 1036 MIB = AddDReg(MIB, DestReg, ARM::dsub_2, RegState::DefineNoRead, TRI); 1037 MIB = AddDReg(MIB, DestReg, ARM::dsub_3, RegState::DefineNoRead, TRI); 1038 if (TargetRegisterInfo::isPhysicalRegister(DestReg)) 1039 MIB.addReg(DestReg, RegState::ImplicitDefine); 1040 } 1041 } else 1042 llvm_unreachable("Unknown reg class!"); 1043 break; 1044 case 64: 1045 if (ARM::QQQQPRRegClass.hasSubClassEq(RC)) { 1046 MachineInstrBuilder MIB = 1047 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::VLDMDIA)) 1048 .addFrameIndex(FI)) 1049 .addMemOperand(MMO); 1050 MIB = AddDReg(MIB, DestReg, ARM::dsub_0, RegState::DefineNoRead, TRI); 1051 MIB = AddDReg(MIB, DestReg, ARM::dsub_1, RegState::DefineNoRead, TRI); 1052 MIB = AddDReg(MIB, DestReg, ARM::dsub_2, RegState::DefineNoRead, TRI); 1053 MIB = AddDReg(MIB, DestReg, ARM::dsub_3, RegState::DefineNoRead, TRI); 1054 MIB = AddDReg(MIB, DestReg, ARM::dsub_4, RegState::DefineNoRead, TRI); 1055 MIB = AddDReg(MIB, DestReg, ARM::dsub_5, RegState::DefineNoRead, TRI); 1056 MIB = AddDReg(MIB, DestReg, ARM::dsub_6, RegState::DefineNoRead, TRI); 1057 MIB = AddDReg(MIB, DestReg, ARM::dsub_7, RegState::DefineNoRead, TRI); 1058 if (TargetRegisterInfo::isPhysicalRegister(DestReg)) 1059 MIB.addReg(DestReg, RegState::ImplicitDefine); 1060 } else 1061 llvm_unreachable("Unknown reg class!"); 1062 break; 1063 default: 1064 llvm_unreachable("Unknown regclass!"); 1065 } 1066 } 1067 1068 unsigned 1069 ARMBaseInstrInfo::isLoadFromStackSlot(const MachineInstr *MI, 1070 int &FrameIndex) const { 1071 switch (MI->getOpcode()) { 1072 default: break; 1073 case ARM::LDRrs: 1074 case ARM::t2LDRs: // FIXME: don't use t2LDRs to access frame. 1075 if (MI->getOperand(1).isFI() && 1076 MI->getOperand(2).isReg() && 1077 MI->getOperand(3).isImm() && 1078 MI->getOperand(2).getReg() == 0 && 1079 MI->getOperand(3).getImm() == 0) { 1080 FrameIndex = MI->getOperand(1).getIndex(); 1081 return MI->getOperand(0).getReg(); 1082 } 1083 break; 1084 case ARM::LDRi12: 1085 case ARM::t2LDRi12: 1086 case ARM::tLDRspi: 1087 case ARM::VLDRD: 1088 case ARM::VLDRS: 1089 if (MI->getOperand(1).isFI() && 1090 MI->getOperand(2).isImm() && 1091 MI->getOperand(2).getImm() == 0) { 1092 FrameIndex = MI->getOperand(1).getIndex(); 1093 return MI->getOperand(0).getReg(); 1094 } 1095 break; 1096 case ARM::VLD1q64: 1097 case ARM::VLD1d64TPseudo: 1098 case ARM::VLD1d64QPseudo: 1099 if (MI->getOperand(1).isFI() && 1100 MI->getOperand(0).getSubReg() == 0) { 1101 FrameIndex = MI->getOperand(1).getIndex(); 1102 return MI->getOperand(0).getReg(); 1103 } 1104 break; 1105 case ARM::VLDMQIA: 1106 if (MI->getOperand(1).isFI() && 1107 MI->getOperand(0).getSubReg() == 0) { 1108 FrameIndex = MI->getOperand(1).getIndex(); 1109 return MI->getOperand(0).getReg(); 1110 } 1111 break; 1112 } 1113 1114 return 0; 1115 } 1116 1117 unsigned ARMBaseInstrInfo::isLoadFromStackSlotPostFE(const MachineInstr *MI, 1118 int &FrameIndex) const { 1119 const MachineMemOperand *Dummy; 1120 return MI->mayLoad() && hasLoadFromStackSlot(MI, Dummy, FrameIndex); 1121 } 1122 1123 bool ARMBaseInstrInfo::expandPostRAPseudo(MachineBasicBlock::iterator MI) const{ 1124 // This hook gets to expand COPY instructions before they become 1125 // copyPhysReg() calls. Look for VMOVS instructions that can legally be 1126 // widened to VMOVD. We prefer the VMOVD when possible because it may be 1127 // changed into a VORR that can go down the NEON pipeline. 1128 if (!WidenVMOVS || !MI->isCopy() || Subtarget.isCortexA15()) 1129 return false; 1130 1131 // Look for a copy between even S-registers. That is where we keep floats 1132 // when using NEON v2f32 instructions for f32 arithmetic. 1133 unsigned DstRegS = MI->getOperand(0).getReg(); 1134 unsigned SrcRegS = MI->getOperand(1).getReg(); 1135 if (!ARM::SPRRegClass.contains(DstRegS, SrcRegS)) 1136 return false; 1137 1138 const TargetRegisterInfo *TRI = &getRegisterInfo(); 1139 unsigned DstRegD = TRI->getMatchingSuperReg(DstRegS, ARM::ssub_0, 1140 &ARM::DPRRegClass); 1141 unsigned SrcRegD = TRI->getMatchingSuperReg(SrcRegS, ARM::ssub_0, 1142 &ARM::DPRRegClass); 1143 if (!DstRegD || !SrcRegD) 1144 return false; 1145 1146 // We want to widen this into a DstRegD = VMOVD SrcRegD copy. This is only 1147 // legal if the COPY already defines the full DstRegD, and it isn't a 1148 // sub-register insertion. 1149 if (!MI->definesRegister(DstRegD, TRI) || MI->readsRegister(DstRegD, TRI)) 1150 return false; 1151 1152 // A dead copy shouldn't show up here, but reject it just in case. 1153 if (MI->getOperand(0).isDead()) 1154 return false; 1155 1156 // All clear, widen the COPY. 1157 DEBUG(dbgs() << "widening: " << *MI); 1158 MachineInstrBuilder MIB(*MI->getParent()->getParent(), MI); 1159 1160 // Get rid of the old <imp-def> of DstRegD. Leave it if it defines a Q-reg 1161 // or some other super-register. 1162 int ImpDefIdx = MI->findRegisterDefOperandIdx(DstRegD); 1163 if (ImpDefIdx != -1) 1164 MI->RemoveOperand(ImpDefIdx); 1165 1166 // Change the opcode and operands. 1167 MI->setDesc(get(ARM::VMOVD)); 1168 MI->getOperand(0).setReg(DstRegD); 1169 MI->getOperand(1).setReg(SrcRegD); 1170 AddDefaultPred(MIB); 1171 1172 // We are now reading SrcRegD instead of SrcRegS. This may upset the 1173 // register scavenger and machine verifier, so we need to indicate that we 1174 // are reading an undefined value from SrcRegD, but a proper value from 1175 // SrcRegS. 1176 MI->getOperand(1).setIsUndef(); 1177 MIB.addReg(SrcRegS, RegState::Implicit); 1178 1179 // SrcRegD may actually contain an unrelated value in the ssub_1 1180 // sub-register. Don't kill it. Only kill the ssub_0 sub-register. 1181 if (MI->getOperand(1).isKill()) { 1182 MI->getOperand(1).setIsKill(false); 1183 MI->addRegisterKilled(SrcRegS, TRI, true); 1184 } 1185 1186 DEBUG(dbgs() << "replaced by: " << *MI); 1187 return true; 1188 } 1189 1190 MachineInstr* 1191 ARMBaseInstrInfo::emitFrameIndexDebugValue(MachineFunction &MF, 1192 int FrameIx, uint64_t Offset, 1193 const MDNode *MDPtr, 1194 DebugLoc DL) const { 1195 MachineInstrBuilder MIB = BuildMI(MF, DL, get(ARM::DBG_VALUE)) 1196 .addFrameIndex(FrameIx).addImm(0).addImm(Offset).addMetadata(MDPtr); 1197 return &*MIB; 1198 } 1199 1200 /// Create a copy of a const pool value. Update CPI to the new index and return 1201 /// the label UID. 1202 static unsigned duplicateCPV(MachineFunction &MF, unsigned &CPI) { 1203 MachineConstantPool *MCP = MF.getConstantPool(); 1204 ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>(); 1205 1206 const MachineConstantPoolEntry &MCPE = MCP->getConstants()[CPI]; 1207 assert(MCPE.isMachineConstantPoolEntry() && 1208 "Expecting a machine constantpool entry!"); 1209 ARMConstantPoolValue *ACPV = 1210 static_cast<ARMConstantPoolValue*>(MCPE.Val.MachineCPVal); 1211 1212 unsigned PCLabelId = AFI->createPICLabelUId(); 1213 ARMConstantPoolValue *NewCPV = 0; 1214 // FIXME: The below assumes PIC relocation model and that the function 1215 // is Thumb mode (t1 or t2). PCAdjustment would be 8 for ARM mode PIC, and 1216 // zero for non-PIC in ARM or Thumb. The callers are all of thumb LDR 1217 // instructions, so that's probably OK, but is PIC always correct when 1218 // we get here? 1219 if (ACPV->isGlobalValue()) 1220 NewCPV = ARMConstantPoolConstant:: 1221 Create(cast<ARMConstantPoolConstant>(ACPV)->getGV(), PCLabelId, 1222 ARMCP::CPValue, 4); 1223 else if (ACPV->isExtSymbol()) 1224 NewCPV = ARMConstantPoolSymbol:: 1225 Create(MF.getFunction()->getContext(), 1226 cast<ARMConstantPoolSymbol>(ACPV)->getSymbol(), PCLabelId, 4); 1227 else if (ACPV->isBlockAddress()) 1228 NewCPV = ARMConstantPoolConstant:: 1229 Create(cast<ARMConstantPoolConstant>(ACPV)->getBlockAddress(), PCLabelId, 1230 ARMCP::CPBlockAddress, 4); 1231 else if (ACPV->isLSDA()) 1232 NewCPV = ARMConstantPoolConstant::Create(MF.getFunction(), PCLabelId, 1233 ARMCP::CPLSDA, 4); 1234 else if (ACPV->isMachineBasicBlock()) 1235 NewCPV = ARMConstantPoolMBB:: 1236 Create(MF.getFunction()->getContext(), 1237 cast<ARMConstantPoolMBB>(ACPV)->getMBB(), PCLabelId, 4); 1238 else 1239 llvm_unreachable("Unexpected ARM constantpool value type!!"); 1240 CPI = MCP->getConstantPoolIndex(NewCPV, MCPE.getAlignment()); 1241 return PCLabelId; 1242 } 1243 1244 void ARMBaseInstrInfo:: 1245 reMaterialize(MachineBasicBlock &MBB, 1246 MachineBasicBlock::iterator I, 1247 unsigned DestReg, unsigned SubIdx, 1248 const MachineInstr *Orig, 1249 const TargetRegisterInfo &TRI) const { 1250 unsigned Opcode = Orig->getOpcode(); 1251 switch (Opcode) { 1252 default: { 1253 MachineInstr *MI = MBB.getParent()->CloneMachineInstr(Orig); 1254 MI->substituteRegister(Orig->getOperand(0).getReg(), DestReg, SubIdx, TRI); 1255 MBB.insert(I, MI); 1256 break; 1257 } 1258 case ARM::tLDRpci_pic: 1259 case ARM::t2LDRpci_pic: { 1260 MachineFunction &MF = *MBB.getParent(); 1261 unsigned CPI = Orig->getOperand(1).getIndex(); 1262 unsigned PCLabelId = duplicateCPV(MF, CPI); 1263 MachineInstrBuilder MIB = BuildMI(MBB, I, Orig->getDebugLoc(), get(Opcode), 1264 DestReg) 1265 .addConstantPoolIndex(CPI).addImm(PCLabelId); 1266 MIB->setMemRefs(Orig->memoperands_begin(), Orig->memoperands_end()); 1267 break; 1268 } 1269 } 1270 } 1271 1272 MachineInstr * 1273 ARMBaseInstrInfo::duplicate(MachineInstr *Orig, MachineFunction &MF) const { 1274 MachineInstr *MI = TargetInstrInfo::duplicate(Orig, MF); 1275 switch(Orig->getOpcode()) { 1276 case ARM::tLDRpci_pic: 1277 case ARM::t2LDRpci_pic: { 1278 unsigned CPI = Orig->getOperand(1).getIndex(); 1279 unsigned PCLabelId = duplicateCPV(MF, CPI); 1280 Orig->getOperand(1).setIndex(CPI); 1281 Orig->getOperand(2).setImm(PCLabelId); 1282 break; 1283 } 1284 } 1285 return MI; 1286 } 1287 1288 bool ARMBaseInstrInfo::produceSameValue(const MachineInstr *MI0, 1289 const MachineInstr *MI1, 1290 const MachineRegisterInfo *MRI) const { 1291 int Opcode = MI0->getOpcode(); 1292 if (Opcode == ARM::t2LDRpci || 1293 Opcode == ARM::t2LDRpci_pic || 1294 Opcode == ARM::tLDRpci || 1295 Opcode == ARM::tLDRpci_pic || 1296 Opcode == ARM::MOV_ga_dyn || 1297 Opcode == ARM::MOV_ga_pcrel || 1298 Opcode == ARM::MOV_ga_pcrel_ldr || 1299 Opcode == ARM::t2MOV_ga_dyn || 1300 Opcode == ARM::t2MOV_ga_pcrel) { 1301 if (MI1->getOpcode() != Opcode) 1302 return false; 1303 if (MI0->getNumOperands() != MI1->getNumOperands()) 1304 return false; 1305 1306 const MachineOperand &MO0 = MI0->getOperand(1); 1307 const MachineOperand &MO1 = MI1->getOperand(1); 1308 if (MO0.getOffset() != MO1.getOffset()) 1309 return false; 1310 1311 if (Opcode == ARM::MOV_ga_dyn || 1312 Opcode == ARM::MOV_ga_pcrel || 1313 Opcode == ARM::MOV_ga_pcrel_ldr || 1314 Opcode == ARM::t2MOV_ga_dyn || 1315 Opcode == ARM::t2MOV_ga_pcrel) 1316 // Ignore the PC labels. 1317 return MO0.getGlobal() == MO1.getGlobal(); 1318 1319 const MachineFunction *MF = MI0->getParent()->getParent(); 1320 const MachineConstantPool *MCP = MF->getConstantPool(); 1321 int CPI0 = MO0.getIndex(); 1322 int CPI1 = MO1.getIndex(); 1323 const MachineConstantPoolEntry &MCPE0 = MCP->getConstants()[CPI0]; 1324 const MachineConstantPoolEntry &MCPE1 = MCP->getConstants()[CPI1]; 1325 bool isARMCP0 = MCPE0.isMachineConstantPoolEntry(); 1326 bool isARMCP1 = MCPE1.isMachineConstantPoolEntry(); 1327 if (isARMCP0 && isARMCP1) { 1328 ARMConstantPoolValue *ACPV0 = 1329 static_cast<ARMConstantPoolValue*>(MCPE0.Val.MachineCPVal); 1330 ARMConstantPoolValue *ACPV1 = 1331 static_cast<ARMConstantPoolValue*>(MCPE1.Val.MachineCPVal); 1332 return ACPV0->hasSameValue(ACPV1); 1333 } else if (!isARMCP0 && !isARMCP1) { 1334 return MCPE0.Val.ConstVal == MCPE1.Val.ConstVal; 1335 } 1336 return false; 1337 } else if (Opcode == ARM::PICLDR) { 1338 if (MI1->getOpcode() != Opcode) 1339 return false; 1340 if (MI0->getNumOperands() != MI1->getNumOperands()) 1341 return false; 1342 1343 unsigned Addr0 = MI0->getOperand(1).getReg(); 1344 unsigned Addr1 = MI1->getOperand(1).getReg(); 1345 if (Addr0 != Addr1) { 1346 if (!MRI || 1347 !TargetRegisterInfo::isVirtualRegister(Addr0) || 1348 !TargetRegisterInfo::isVirtualRegister(Addr1)) 1349 return false; 1350 1351 // This assumes SSA form. 1352 MachineInstr *Def0 = MRI->getVRegDef(Addr0); 1353 MachineInstr *Def1 = MRI->getVRegDef(Addr1); 1354 // Check if the loaded value, e.g. a constantpool of a global address, are 1355 // the same. 1356 if (!produceSameValue(Def0, Def1, MRI)) 1357 return false; 1358 } 1359 1360 for (unsigned i = 3, e = MI0->getNumOperands(); i != e; ++i) { 1361 // %vreg12<def> = PICLDR %vreg11, 0, pred:14, pred:%noreg 1362 const MachineOperand &MO0 = MI0->getOperand(i); 1363 const MachineOperand &MO1 = MI1->getOperand(i); 1364 if (!MO0.isIdenticalTo(MO1)) 1365 return false; 1366 } 1367 return true; 1368 } 1369 1370 return MI0->isIdenticalTo(MI1, MachineInstr::IgnoreVRegDefs); 1371 } 1372 1373 /// areLoadsFromSameBasePtr - This is used by the pre-regalloc scheduler to 1374 /// determine if two loads are loading from the same base address. It should 1375 /// only return true if the base pointers are the same and the only differences 1376 /// between the two addresses is the offset. It also returns the offsets by 1377 /// reference. 1378 /// 1379 /// FIXME: remove this in favor of the MachineInstr interface once pre-RA-sched 1380 /// is permanently disabled. 1381 bool ARMBaseInstrInfo::areLoadsFromSameBasePtr(SDNode *Load1, SDNode *Load2, 1382 int64_t &Offset1, 1383 int64_t &Offset2) const { 1384 // Don't worry about Thumb: just ARM and Thumb2. 1385 if (Subtarget.isThumb1Only()) return false; 1386 1387 if (!Load1->isMachineOpcode() || !Load2->isMachineOpcode()) 1388 return false; 1389 1390 switch (Load1->getMachineOpcode()) { 1391 default: 1392 return false; 1393 case ARM::LDRi12: 1394 case ARM::LDRBi12: 1395 case ARM::LDRD: 1396 case ARM::LDRH: 1397 case ARM::LDRSB: 1398 case ARM::LDRSH: 1399 case ARM::VLDRD: 1400 case ARM::VLDRS: 1401 case ARM::t2LDRi8: 1402 case ARM::t2LDRDi8: 1403 case ARM::t2LDRSHi8: 1404 case ARM::t2LDRi12: 1405 case ARM::t2LDRSHi12: 1406 break; 1407 } 1408 1409 switch (Load2->getMachineOpcode()) { 1410 default: 1411 return false; 1412 case ARM::LDRi12: 1413 case ARM::LDRBi12: 1414 case ARM::LDRD: 1415 case ARM::LDRH: 1416 case ARM::LDRSB: 1417 case ARM::LDRSH: 1418 case ARM::VLDRD: 1419 case ARM::VLDRS: 1420 case ARM::t2LDRi8: 1421 case ARM::t2LDRSHi8: 1422 case ARM::t2LDRi12: 1423 case ARM::t2LDRSHi12: 1424 break; 1425 } 1426 1427 // Check if base addresses and chain operands match. 1428 if (Load1->getOperand(0) != Load2->getOperand(0) || 1429 Load1->getOperand(4) != Load2->getOperand(4)) 1430 return false; 1431 1432 // Index should be Reg0. 1433 if (Load1->getOperand(3) != Load2->getOperand(3)) 1434 return false; 1435 1436 // Determine the offsets. 1437 if (isa<ConstantSDNode>(Load1->getOperand(1)) && 1438 isa<ConstantSDNode>(Load2->getOperand(1))) { 1439 Offset1 = cast<ConstantSDNode>(Load1->getOperand(1))->getSExtValue(); 1440 Offset2 = cast<ConstantSDNode>(Load2->getOperand(1))->getSExtValue(); 1441 return true; 1442 } 1443 1444 return false; 1445 } 1446 1447 /// shouldScheduleLoadsNear - This is a used by the pre-regalloc scheduler to 1448 /// determine (in conjunction with areLoadsFromSameBasePtr) if two loads should 1449 /// be scheduled togther. On some targets if two loads are loading from 1450 /// addresses in the same cache line, it's better if they are scheduled 1451 /// together. This function takes two integers that represent the load offsets 1452 /// from the common base address. It returns true if it decides it's desirable 1453 /// to schedule the two loads together. "NumLoads" is the number of loads that 1454 /// have already been scheduled after Load1. 1455 /// 1456 /// FIXME: remove this in favor of the MachineInstr interface once pre-RA-sched 1457 /// is permanently disabled. 1458 bool ARMBaseInstrInfo::shouldScheduleLoadsNear(SDNode *Load1, SDNode *Load2, 1459 int64_t Offset1, int64_t Offset2, 1460 unsigned NumLoads) const { 1461 // Don't worry about Thumb: just ARM and Thumb2. 1462 if (Subtarget.isThumb1Only()) return false; 1463 1464 assert(Offset2 > Offset1); 1465 1466 if ((Offset2 - Offset1) / 8 > 64) 1467 return false; 1468 1469 if (Load1->getMachineOpcode() != Load2->getMachineOpcode()) 1470 return false; // FIXME: overly conservative? 1471 1472 // Four loads in a row should be sufficient. 1473 if (NumLoads >= 3) 1474 return false; 1475 1476 return true; 1477 } 1478 1479 bool ARMBaseInstrInfo::isSchedulingBoundary(const MachineInstr *MI, 1480 const MachineBasicBlock *MBB, 1481 const MachineFunction &MF) const { 1482 // Debug info is never a scheduling boundary. It's necessary to be explicit 1483 // due to the special treatment of IT instructions below, otherwise a 1484 // dbg_value followed by an IT will result in the IT instruction being 1485 // considered a scheduling hazard, which is wrong. It should be the actual 1486 // instruction preceding the dbg_value instruction(s), just like it is 1487 // when debug info is not present. 1488 if (MI->isDebugValue()) 1489 return false; 1490 1491 // Terminators and labels can't be scheduled around. 1492 if (MI->isTerminator() || MI->isLabel()) 1493 return true; 1494 1495 // Treat the start of the IT block as a scheduling boundary, but schedule 1496 // t2IT along with all instructions following it. 1497 // FIXME: This is a big hammer. But the alternative is to add all potential 1498 // true and anti dependencies to IT block instructions as implicit operands 1499 // to the t2IT instruction. The added compile time and complexity does not 1500 // seem worth it. 1501 MachineBasicBlock::const_iterator I = MI; 1502 // Make sure to skip any dbg_value instructions 1503 while (++I != MBB->end() && I->isDebugValue()) 1504 ; 1505 if (I != MBB->end() && I->getOpcode() == ARM::t2IT) 1506 return true; 1507 1508 // Don't attempt to schedule around any instruction that defines 1509 // a stack-oriented pointer, as it's unlikely to be profitable. This 1510 // saves compile time, because it doesn't require every single 1511 // stack slot reference to depend on the instruction that does the 1512 // modification. 1513 // Calls don't actually change the stack pointer, even if they have imp-defs. 1514 // No ARM calling conventions change the stack pointer. (X86 calling 1515 // conventions sometimes do). 1516 if (!MI->isCall() && MI->definesRegister(ARM::SP)) 1517 return true; 1518 1519 return false; 1520 } 1521 1522 bool ARMBaseInstrInfo:: 1523 isProfitableToIfCvt(MachineBasicBlock &MBB, 1524 unsigned NumCycles, unsigned ExtraPredCycles, 1525 const BranchProbability &Probability) const { 1526 if (!NumCycles) 1527 return false; 1528 1529 // Attempt to estimate the relative costs of predication versus branching. 1530 unsigned UnpredCost = Probability.getNumerator() * NumCycles; 1531 UnpredCost /= Probability.getDenominator(); 1532 UnpredCost += 1; // The branch itself 1533 UnpredCost += Subtarget.getMispredictionPenalty() / 10; 1534 1535 return (NumCycles + ExtraPredCycles) <= UnpredCost; 1536 } 1537 1538 bool ARMBaseInstrInfo:: 1539 isProfitableToIfCvt(MachineBasicBlock &TMBB, 1540 unsigned TCycles, unsigned TExtra, 1541 MachineBasicBlock &FMBB, 1542 unsigned FCycles, unsigned FExtra, 1543 const BranchProbability &Probability) const { 1544 if (!TCycles || !FCycles) 1545 return false; 1546 1547 // Attempt to estimate the relative costs of predication versus branching. 1548 unsigned TUnpredCost = Probability.getNumerator() * TCycles; 1549 TUnpredCost /= Probability.getDenominator(); 1550 1551 uint32_t Comp = Probability.getDenominator() - Probability.getNumerator(); 1552 unsigned FUnpredCost = Comp * FCycles; 1553 FUnpredCost /= Probability.getDenominator(); 1554 1555 unsigned UnpredCost = TUnpredCost + FUnpredCost; 1556 UnpredCost += 1; // The branch itself 1557 UnpredCost += Subtarget.getMispredictionPenalty() / 10; 1558 1559 return (TCycles + FCycles + TExtra + FExtra) <= UnpredCost; 1560 } 1561 1562 bool 1563 ARMBaseInstrInfo::isProfitableToUnpredicate(MachineBasicBlock &TMBB, 1564 MachineBasicBlock &FMBB) const { 1565 // Reduce false anti-dependencies to let Swift's out-of-order execution 1566 // engine do its thing. 1567 return Subtarget.isSwift(); 1568 } 1569 1570 /// getInstrPredicate - If instruction is predicated, returns its predicate 1571 /// condition, otherwise returns AL. It also returns the condition code 1572 /// register by reference. 1573 ARMCC::CondCodes 1574 llvm::getInstrPredicate(const MachineInstr *MI, unsigned &PredReg) { 1575 int PIdx = MI->findFirstPredOperandIdx(); 1576 if (PIdx == -1) { 1577 PredReg = 0; 1578 return ARMCC::AL; 1579 } 1580 1581 PredReg = MI->getOperand(PIdx+1).getReg(); 1582 return (ARMCC::CondCodes)MI->getOperand(PIdx).getImm(); 1583 } 1584 1585 1586 int llvm::getMatchingCondBranchOpcode(int Opc) { 1587 if (Opc == ARM::B) 1588 return ARM::Bcc; 1589 if (Opc == ARM::tB) 1590 return ARM::tBcc; 1591 if (Opc == ARM::t2B) 1592 return ARM::t2Bcc; 1593 1594 llvm_unreachable("Unknown unconditional branch opcode!"); 1595 } 1596 1597 /// commuteInstruction - Handle commutable instructions. 1598 MachineInstr * 1599 ARMBaseInstrInfo::commuteInstruction(MachineInstr *MI, bool NewMI) const { 1600 switch (MI->getOpcode()) { 1601 case ARM::MOVCCr: 1602 case ARM::t2MOVCCr: { 1603 // MOVCC can be commuted by inverting the condition. 1604 unsigned PredReg = 0; 1605 ARMCC::CondCodes CC = getInstrPredicate(MI, PredReg); 1606 // MOVCC AL can't be inverted. Shouldn't happen. 1607 if (CC == ARMCC::AL || PredReg != ARM::CPSR) 1608 return NULL; 1609 MI = TargetInstrInfo::commuteInstruction(MI, NewMI); 1610 if (!MI) 1611 return NULL; 1612 // After swapping the MOVCC operands, also invert the condition. 1613 MI->getOperand(MI->findFirstPredOperandIdx()) 1614 .setImm(ARMCC::getOppositeCondition(CC)); 1615 return MI; 1616 } 1617 } 1618 return TargetInstrInfo::commuteInstruction(MI, NewMI); 1619 } 1620 1621 /// Identify instructions that can be folded into a MOVCC instruction, and 1622 /// return the defining instruction. 1623 static MachineInstr *canFoldIntoMOVCC(unsigned Reg, 1624 const MachineRegisterInfo &MRI, 1625 const TargetInstrInfo *TII) { 1626 if (!TargetRegisterInfo::isVirtualRegister(Reg)) 1627 return 0; 1628 if (!MRI.hasOneNonDBGUse(Reg)) 1629 return 0; 1630 MachineInstr *MI = MRI.getVRegDef(Reg); 1631 if (!MI) 1632 return 0; 1633 // MI is folded into the MOVCC by predicating it. 1634 if (!MI->isPredicable()) 1635 return 0; 1636 // Check if MI has any non-dead defs or physreg uses. This also detects 1637 // predicated instructions which will be reading CPSR. 1638 for (unsigned i = 1, e = MI->getNumOperands(); i != e; ++i) { 1639 const MachineOperand &MO = MI->getOperand(i); 1640 // Reject frame index operands, PEI can't handle the predicated pseudos. 1641 if (MO.isFI() || MO.isCPI() || MO.isJTI()) 1642 return 0; 1643 if (!MO.isReg()) 1644 continue; 1645 // MI can't have any tied operands, that would conflict with predication. 1646 if (MO.isTied()) 1647 return 0; 1648 if (TargetRegisterInfo::isPhysicalRegister(MO.getReg())) 1649 return 0; 1650 if (MO.isDef() && !MO.isDead()) 1651 return 0; 1652 } 1653 bool DontMoveAcrossStores = true; 1654 if (!MI->isSafeToMove(TII, /* AliasAnalysis = */ 0, DontMoveAcrossStores)) 1655 return 0; 1656 return MI; 1657 } 1658 1659 bool ARMBaseInstrInfo::analyzeSelect(const MachineInstr *MI, 1660 SmallVectorImpl<MachineOperand> &Cond, 1661 unsigned &TrueOp, unsigned &FalseOp, 1662 bool &Optimizable) const { 1663 assert((MI->getOpcode() == ARM::MOVCCr || MI->getOpcode() == ARM::t2MOVCCr) && 1664 "Unknown select instruction"); 1665 // MOVCC operands: 1666 // 0: Def. 1667 // 1: True use. 1668 // 2: False use. 1669 // 3: Condition code. 1670 // 4: CPSR use. 1671 TrueOp = 1; 1672 FalseOp = 2; 1673 Cond.push_back(MI->getOperand(3)); 1674 Cond.push_back(MI->getOperand(4)); 1675 // We can always fold a def. 1676 Optimizable = true; 1677 return false; 1678 } 1679 1680 MachineInstr *ARMBaseInstrInfo::optimizeSelect(MachineInstr *MI, 1681 bool PreferFalse) const { 1682 assert((MI->getOpcode() == ARM::MOVCCr || MI->getOpcode() == ARM::t2MOVCCr) && 1683 "Unknown select instruction"); 1684 const MachineRegisterInfo &MRI = MI->getParent()->getParent()->getRegInfo(); 1685 MachineInstr *DefMI = canFoldIntoMOVCC(MI->getOperand(2).getReg(), MRI, this); 1686 bool Invert = !DefMI; 1687 if (!DefMI) 1688 DefMI = canFoldIntoMOVCC(MI->getOperand(1).getReg(), MRI, this); 1689 if (!DefMI) 1690 return 0; 1691 1692 // Create a new predicated version of DefMI. 1693 // Rfalse is the first use. 1694 MachineInstrBuilder NewMI = BuildMI(*MI->getParent(), MI, MI->getDebugLoc(), 1695 DefMI->getDesc(), 1696 MI->getOperand(0).getReg()); 1697 1698 // Copy all the DefMI operands, excluding its (null) predicate. 1699 const MCInstrDesc &DefDesc = DefMI->getDesc(); 1700 for (unsigned i = 1, e = DefDesc.getNumOperands(); 1701 i != e && !DefDesc.OpInfo[i].isPredicate(); ++i) 1702 NewMI.addOperand(DefMI->getOperand(i)); 1703 1704 unsigned CondCode = MI->getOperand(3).getImm(); 1705 if (Invert) 1706 NewMI.addImm(ARMCC::getOppositeCondition(ARMCC::CondCodes(CondCode))); 1707 else 1708 NewMI.addImm(CondCode); 1709 NewMI.addOperand(MI->getOperand(4)); 1710 1711 // DefMI is not the -S version that sets CPSR, so add an optional %noreg. 1712 if (NewMI->hasOptionalDef()) 1713 AddDefaultCC(NewMI); 1714 1715 // The output register value when the predicate is false is an implicit 1716 // register operand tied to the first def. 1717 // The tie makes the register allocator ensure the FalseReg is allocated the 1718 // same register as operand 0. 1719 MachineOperand FalseReg = MI->getOperand(Invert ? 2 : 1); 1720 FalseReg.setImplicit(); 1721 NewMI.addOperand(FalseReg); 1722 NewMI->tieOperands(0, NewMI->getNumOperands() - 1); 1723 1724 // The caller will erase MI, but not DefMI. 1725 DefMI->eraseFromParent(); 1726 return NewMI; 1727 } 1728 1729 /// Map pseudo instructions that imply an 'S' bit onto real opcodes. Whether the 1730 /// instruction is encoded with an 'S' bit is determined by the optional CPSR 1731 /// def operand. 1732 /// 1733 /// This will go away once we can teach tblgen how to set the optional CPSR def 1734 /// operand itself. 1735 struct AddSubFlagsOpcodePair { 1736 uint16_t PseudoOpc; 1737 uint16_t MachineOpc; 1738 }; 1739 1740 static const AddSubFlagsOpcodePair AddSubFlagsOpcodeMap[] = { 1741 {ARM::ADDSri, ARM::ADDri}, 1742 {ARM::ADDSrr, ARM::ADDrr}, 1743 {ARM::ADDSrsi, ARM::ADDrsi}, 1744 {ARM::ADDSrsr, ARM::ADDrsr}, 1745 1746 {ARM::SUBSri, ARM::SUBri}, 1747 {ARM::SUBSrr, ARM::SUBrr}, 1748 {ARM::SUBSrsi, ARM::SUBrsi}, 1749 {ARM::SUBSrsr, ARM::SUBrsr}, 1750 1751 {ARM::RSBSri, ARM::RSBri}, 1752 {ARM::RSBSrsi, ARM::RSBrsi}, 1753 {ARM::RSBSrsr, ARM::RSBrsr}, 1754 1755 {ARM::t2ADDSri, ARM::t2ADDri}, 1756 {ARM::t2ADDSrr, ARM::t2ADDrr}, 1757 {ARM::t2ADDSrs, ARM::t2ADDrs}, 1758 1759 {ARM::t2SUBSri, ARM::t2SUBri}, 1760 {ARM::t2SUBSrr, ARM::t2SUBrr}, 1761 {ARM::t2SUBSrs, ARM::t2SUBrs}, 1762 1763 {ARM::t2RSBSri, ARM::t2RSBri}, 1764 {ARM::t2RSBSrs, ARM::t2RSBrs}, 1765 }; 1766 1767 unsigned llvm::convertAddSubFlagsOpcode(unsigned OldOpc) { 1768 for (unsigned i = 0, e = array_lengthof(AddSubFlagsOpcodeMap); i != e; ++i) 1769 if (OldOpc == AddSubFlagsOpcodeMap[i].PseudoOpc) 1770 return AddSubFlagsOpcodeMap[i].MachineOpc; 1771 return 0; 1772 } 1773 1774 void llvm::emitARMRegPlusImmediate(MachineBasicBlock &MBB, 1775 MachineBasicBlock::iterator &MBBI, DebugLoc dl, 1776 unsigned DestReg, unsigned BaseReg, int NumBytes, 1777 ARMCC::CondCodes Pred, unsigned PredReg, 1778 const ARMBaseInstrInfo &TII, unsigned MIFlags) { 1779 bool isSub = NumBytes < 0; 1780 if (isSub) NumBytes = -NumBytes; 1781 1782 while (NumBytes) { 1783 unsigned RotAmt = ARM_AM::getSOImmValRotate(NumBytes); 1784 unsigned ThisVal = NumBytes & ARM_AM::rotr32(0xFF, RotAmt); 1785 assert(ThisVal && "Didn't extract field correctly"); 1786 1787 // We will handle these bits from offset, clear them. 1788 NumBytes &= ~ThisVal; 1789 1790 assert(ARM_AM::getSOImmVal(ThisVal) != -1 && "Bit extraction didn't work?"); 1791 1792 // Build the new ADD / SUB. 1793 unsigned Opc = isSub ? ARM::SUBri : ARM::ADDri; 1794 BuildMI(MBB, MBBI, dl, TII.get(Opc), DestReg) 1795 .addReg(BaseReg, RegState::Kill).addImm(ThisVal) 1796 .addImm((unsigned)Pred).addReg(PredReg).addReg(0) 1797 .setMIFlags(MIFlags); 1798 BaseReg = DestReg; 1799 } 1800 } 1801 1802 bool llvm::rewriteARMFrameIndex(MachineInstr &MI, unsigned FrameRegIdx, 1803 unsigned FrameReg, int &Offset, 1804 const ARMBaseInstrInfo &TII) { 1805 unsigned Opcode = MI.getOpcode(); 1806 const MCInstrDesc &Desc = MI.getDesc(); 1807 unsigned AddrMode = (Desc.TSFlags & ARMII::AddrModeMask); 1808 bool isSub = false; 1809 1810 // Memory operands in inline assembly always use AddrMode2. 1811 if (Opcode == ARM::INLINEASM) 1812 AddrMode = ARMII::AddrMode2; 1813 1814 if (Opcode == ARM::ADDri) { 1815 Offset += MI.getOperand(FrameRegIdx+1).getImm(); 1816 if (Offset == 0) { 1817 // Turn it into a move. 1818 MI.setDesc(TII.get(ARM::MOVr)); 1819 MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false); 1820 MI.RemoveOperand(FrameRegIdx+1); 1821 Offset = 0; 1822 return true; 1823 } else if (Offset < 0) { 1824 Offset = -Offset; 1825 isSub = true; 1826 MI.setDesc(TII.get(ARM::SUBri)); 1827 } 1828 1829 // Common case: small offset, fits into instruction. 1830 if (ARM_AM::getSOImmVal(Offset) != -1) { 1831 // Replace the FrameIndex with sp / fp 1832 MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false); 1833 MI.getOperand(FrameRegIdx+1).ChangeToImmediate(Offset); 1834 Offset = 0; 1835 return true; 1836 } 1837 1838 // Otherwise, pull as much of the immedidate into this ADDri/SUBri 1839 // as possible. 1840 unsigned RotAmt = ARM_AM::getSOImmValRotate(Offset); 1841 unsigned ThisImmVal = Offset & ARM_AM::rotr32(0xFF, RotAmt); 1842 1843 // We will handle these bits from offset, clear them. 1844 Offset &= ~ThisImmVal; 1845 1846 // Get the properly encoded SOImmVal field. 1847 assert(ARM_AM::getSOImmVal(ThisImmVal) != -1 && 1848 "Bit extraction didn't work?"); 1849 MI.getOperand(FrameRegIdx+1).ChangeToImmediate(ThisImmVal); 1850 } else { 1851 unsigned ImmIdx = 0; 1852 int InstrOffs = 0; 1853 unsigned NumBits = 0; 1854 unsigned Scale = 1; 1855 switch (AddrMode) { 1856 case ARMII::AddrMode_i12: { 1857 ImmIdx = FrameRegIdx + 1; 1858 InstrOffs = MI.getOperand(ImmIdx).getImm(); 1859 NumBits = 12; 1860 break; 1861 } 1862 case ARMII::AddrMode2: { 1863 ImmIdx = FrameRegIdx+2; 1864 InstrOffs = ARM_AM::getAM2Offset(MI.getOperand(ImmIdx).getImm()); 1865 if (ARM_AM::getAM2Op(MI.getOperand(ImmIdx).getImm()) == ARM_AM::sub) 1866 InstrOffs *= -1; 1867 NumBits = 12; 1868 break; 1869 } 1870 case ARMII::AddrMode3: { 1871 ImmIdx = FrameRegIdx+2; 1872 InstrOffs = ARM_AM::getAM3Offset(MI.getOperand(ImmIdx).getImm()); 1873 if (ARM_AM::getAM3Op(MI.getOperand(ImmIdx).getImm()) == ARM_AM::sub) 1874 InstrOffs *= -1; 1875 NumBits = 8; 1876 break; 1877 } 1878 case ARMII::AddrMode4: 1879 case ARMII::AddrMode6: 1880 // Can't fold any offset even if it's zero. 1881 return false; 1882 case ARMII::AddrMode5: { 1883 ImmIdx = FrameRegIdx+1; 1884 InstrOffs = ARM_AM::getAM5Offset(MI.getOperand(ImmIdx).getImm()); 1885 if (ARM_AM::getAM5Op(MI.getOperand(ImmIdx).getImm()) == ARM_AM::sub) 1886 InstrOffs *= -1; 1887 NumBits = 8; 1888 Scale = 4; 1889 break; 1890 } 1891 default: 1892 llvm_unreachable("Unsupported addressing mode!"); 1893 } 1894 1895 Offset += InstrOffs * Scale; 1896 assert((Offset & (Scale-1)) == 0 && "Can't encode this offset!"); 1897 if (Offset < 0) { 1898 Offset = -Offset; 1899 isSub = true; 1900 } 1901 1902 // Attempt to fold address comp. if opcode has offset bits 1903 if (NumBits > 0) { 1904 // Common case: small offset, fits into instruction. 1905 MachineOperand &ImmOp = MI.getOperand(ImmIdx); 1906 int ImmedOffset = Offset / Scale; 1907 unsigned Mask = (1 << NumBits) - 1; 1908 if ((unsigned)Offset <= Mask * Scale) { 1909 // Replace the FrameIndex with sp 1910 MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false); 1911 // FIXME: When addrmode2 goes away, this will simplify (like the 1912 // T2 version), as the LDR.i12 versions don't need the encoding 1913 // tricks for the offset value. 1914 if (isSub) { 1915 if (AddrMode == ARMII::AddrMode_i12) 1916 ImmedOffset = -ImmedOffset; 1917 else 1918 ImmedOffset |= 1 << NumBits; 1919 } 1920 ImmOp.ChangeToImmediate(ImmedOffset); 1921 Offset = 0; 1922 return true; 1923 } 1924 1925 // Otherwise, it didn't fit. Pull in what we can to simplify the immed. 1926 ImmedOffset = ImmedOffset & Mask; 1927 if (isSub) { 1928 if (AddrMode == ARMII::AddrMode_i12) 1929 ImmedOffset = -ImmedOffset; 1930 else 1931 ImmedOffset |= 1 << NumBits; 1932 } 1933 ImmOp.ChangeToImmediate(ImmedOffset); 1934 Offset &= ~(Mask*Scale); 1935 } 1936 } 1937 1938 Offset = (isSub) ? -Offset : Offset; 1939 return Offset == 0; 1940 } 1941 1942 /// analyzeCompare - For a comparison instruction, return the source registers 1943 /// in SrcReg and SrcReg2 if having two register operands, and the value it 1944 /// compares against in CmpValue. Return true if the comparison instruction 1945 /// can be analyzed. 1946 bool ARMBaseInstrInfo:: 1947 analyzeCompare(const MachineInstr *MI, unsigned &SrcReg, unsigned &SrcReg2, 1948 int &CmpMask, int &CmpValue) const { 1949 switch (MI->getOpcode()) { 1950 default: break; 1951 case ARM::CMPri: 1952 case ARM::t2CMPri: 1953 SrcReg = MI->getOperand(0).getReg(); 1954 SrcReg2 = 0; 1955 CmpMask = ~0; 1956 CmpValue = MI->getOperand(1).getImm(); 1957 return true; 1958 case ARM::CMPrr: 1959 case ARM::t2CMPrr: 1960 SrcReg = MI->getOperand(0).getReg(); 1961 SrcReg2 = MI->getOperand(1).getReg(); 1962 CmpMask = ~0; 1963 CmpValue = 0; 1964 return true; 1965 case ARM::TSTri: 1966 case ARM::t2TSTri: 1967 SrcReg = MI->getOperand(0).getReg(); 1968 SrcReg2 = 0; 1969 CmpMask = MI->getOperand(1).getImm(); 1970 CmpValue = 0; 1971 return true; 1972 } 1973 1974 return false; 1975 } 1976 1977 /// isSuitableForMask - Identify a suitable 'and' instruction that 1978 /// operates on the given source register and applies the same mask 1979 /// as a 'tst' instruction. Provide a limited look-through for copies. 1980 /// When successful, MI will hold the found instruction. 1981 static bool isSuitableForMask(MachineInstr *&MI, unsigned SrcReg, 1982 int CmpMask, bool CommonUse) { 1983 switch (MI->getOpcode()) { 1984 case ARM::ANDri: 1985 case ARM::t2ANDri: 1986 if (CmpMask != MI->getOperand(2).getImm()) 1987 return false; 1988 if (SrcReg == MI->getOperand(CommonUse ? 1 : 0).getReg()) 1989 return true; 1990 break; 1991 case ARM::COPY: { 1992 // Walk down one instruction which is potentially an 'and'. 1993 const MachineInstr &Copy = *MI; 1994 MachineBasicBlock::iterator AND( 1995 llvm::next(MachineBasicBlock::iterator(MI))); 1996 if (AND == MI->getParent()->end()) return false; 1997 MI = AND; 1998 return isSuitableForMask(MI, Copy.getOperand(0).getReg(), 1999 CmpMask, true); 2000 } 2001 } 2002 2003 return false; 2004 } 2005 2006 /// getSwappedCondition - assume the flags are set by MI(a,b), return 2007 /// the condition code if we modify the instructions such that flags are 2008 /// set by MI(b,a). 2009 inline static ARMCC::CondCodes getSwappedCondition(ARMCC::CondCodes CC) { 2010 switch (CC) { 2011 default: return ARMCC::AL; 2012 case ARMCC::EQ: return ARMCC::EQ; 2013 case ARMCC::NE: return ARMCC::NE; 2014 case ARMCC::HS: return ARMCC::LS; 2015 case ARMCC::LO: return ARMCC::HI; 2016 case ARMCC::HI: return ARMCC::LO; 2017 case ARMCC::LS: return ARMCC::HS; 2018 case ARMCC::GE: return ARMCC::LE; 2019 case ARMCC::LT: return ARMCC::GT; 2020 case ARMCC::GT: return ARMCC::LT; 2021 case ARMCC::LE: return ARMCC::GE; 2022 } 2023 } 2024 2025 /// isRedundantFlagInstr - check whether the first instruction, whose only 2026 /// purpose is to update flags, can be made redundant. 2027 /// CMPrr can be made redundant by SUBrr if the operands are the same. 2028 /// CMPri can be made redundant by SUBri if the operands are the same. 2029 /// This function can be extended later on. 2030 inline static bool isRedundantFlagInstr(MachineInstr *CmpI, unsigned SrcReg, 2031 unsigned SrcReg2, int ImmValue, 2032 MachineInstr *OI) { 2033 if ((CmpI->getOpcode() == ARM::CMPrr || 2034 CmpI->getOpcode() == ARM::t2CMPrr) && 2035 (OI->getOpcode() == ARM::SUBrr || 2036 OI->getOpcode() == ARM::t2SUBrr) && 2037 ((OI->getOperand(1).getReg() == SrcReg && 2038 OI->getOperand(2).getReg() == SrcReg2) || 2039 (OI->getOperand(1).getReg() == SrcReg2 && 2040 OI->getOperand(2).getReg() == SrcReg))) 2041 return true; 2042 2043 if ((CmpI->getOpcode() == ARM::CMPri || 2044 CmpI->getOpcode() == ARM::t2CMPri) && 2045 (OI->getOpcode() == ARM::SUBri || 2046 OI->getOpcode() == ARM::t2SUBri) && 2047 OI->getOperand(1).getReg() == SrcReg && 2048 OI->getOperand(2).getImm() == ImmValue) 2049 return true; 2050 return false; 2051 } 2052 2053 /// optimizeCompareInstr - Convert the instruction supplying the argument to the 2054 /// comparison into one that sets the zero bit in the flags register; 2055 /// Remove a redundant Compare instruction if an earlier instruction can set the 2056 /// flags in the same way as Compare. 2057 /// E.g. SUBrr(r1,r2) and CMPrr(r1,r2). We also handle the case where two 2058 /// operands are swapped: SUBrr(r1,r2) and CMPrr(r2,r1), by updating the 2059 /// condition code of instructions which use the flags. 2060 bool ARMBaseInstrInfo:: 2061 optimizeCompareInstr(MachineInstr *CmpInstr, unsigned SrcReg, unsigned SrcReg2, 2062 int CmpMask, int CmpValue, 2063 const MachineRegisterInfo *MRI) const { 2064 // Get the unique definition of SrcReg. 2065 MachineInstr *MI = MRI->getUniqueVRegDef(SrcReg); 2066 if (!MI) return false; 2067 2068 // Masked compares sometimes use the same register as the corresponding 'and'. 2069 if (CmpMask != ~0) { 2070 if (!isSuitableForMask(MI, SrcReg, CmpMask, false) || isPredicated(MI)) { 2071 MI = 0; 2072 for (MachineRegisterInfo::use_iterator UI = MRI->use_begin(SrcReg), 2073 UE = MRI->use_end(); UI != UE; ++UI) { 2074 if (UI->getParent() != CmpInstr->getParent()) continue; 2075 MachineInstr *PotentialAND = &*UI; 2076 if (!isSuitableForMask(PotentialAND, SrcReg, CmpMask, true) || 2077 isPredicated(PotentialAND)) 2078 continue; 2079 MI = PotentialAND; 2080 break; 2081 } 2082 if (!MI) return false; 2083 } 2084 } 2085 2086 // Get ready to iterate backward from CmpInstr. 2087 MachineBasicBlock::iterator I = CmpInstr, E = MI, 2088 B = CmpInstr->getParent()->begin(); 2089 2090 // Early exit if CmpInstr is at the beginning of the BB. 2091 if (I == B) return false; 2092 2093 // There are two possible candidates which can be changed to set CPSR: 2094 // One is MI, the other is a SUB instruction. 2095 // For CMPrr(r1,r2), we are looking for SUB(r1,r2) or SUB(r2,r1). 2096 // For CMPri(r1, CmpValue), we are looking for SUBri(r1, CmpValue). 2097 MachineInstr *Sub = NULL; 2098 if (SrcReg2 != 0) 2099 // MI is not a candidate for CMPrr. 2100 MI = NULL; 2101 else if (MI->getParent() != CmpInstr->getParent() || CmpValue != 0) { 2102 // Conservatively refuse to convert an instruction which isn't in the same 2103 // BB as the comparison. 2104 // For CMPri, we need to check Sub, thus we can't return here. 2105 if (CmpInstr->getOpcode() == ARM::CMPri || 2106 CmpInstr->getOpcode() == ARM::t2CMPri) 2107 MI = NULL; 2108 else 2109 return false; 2110 } 2111 2112 // Check that CPSR isn't set between the comparison instruction and the one we 2113 // want to change. At the same time, search for Sub. 2114 const TargetRegisterInfo *TRI = &getRegisterInfo(); 2115 --I; 2116 for (; I != E; --I) { 2117 const MachineInstr &Instr = *I; 2118 2119 if (Instr.modifiesRegister(ARM::CPSR, TRI) || 2120 Instr.readsRegister(ARM::CPSR, TRI)) 2121 // This instruction modifies or uses CPSR after the one we want to 2122 // change. We can't do this transformation. 2123 return false; 2124 2125 // Check whether CmpInstr can be made redundant by the current instruction. 2126 if (isRedundantFlagInstr(CmpInstr, SrcReg, SrcReg2, CmpValue, &*I)) { 2127 Sub = &*I; 2128 break; 2129 } 2130 2131 if (I == B) 2132 // The 'and' is below the comparison instruction. 2133 return false; 2134 } 2135 2136 // Return false if no candidates exist. 2137 if (!MI && !Sub) 2138 return false; 2139 2140 // The single candidate is called MI. 2141 if (!MI) MI = Sub; 2142 2143 // We can't use a predicated instruction - it doesn't always write the flags. 2144 if (isPredicated(MI)) 2145 return false; 2146 2147 switch (MI->getOpcode()) { 2148 default: break; 2149 case ARM::RSBrr: 2150 case ARM::RSBri: 2151 case ARM::RSCrr: 2152 case ARM::RSCri: 2153 case ARM::ADDrr: 2154 case ARM::ADDri: 2155 case ARM::ADCrr: 2156 case ARM::ADCri: 2157 case ARM::SUBrr: 2158 case ARM::SUBri: 2159 case ARM::SBCrr: 2160 case ARM::SBCri: 2161 case ARM::t2RSBri: 2162 case ARM::t2ADDrr: 2163 case ARM::t2ADDri: 2164 case ARM::t2ADCrr: 2165 case ARM::t2ADCri: 2166 case ARM::t2SUBrr: 2167 case ARM::t2SUBri: 2168 case ARM::t2SBCrr: 2169 case ARM::t2SBCri: 2170 case ARM::ANDrr: 2171 case ARM::ANDri: 2172 case ARM::t2ANDrr: 2173 case ARM::t2ANDri: 2174 case ARM::ORRrr: 2175 case ARM::ORRri: 2176 case ARM::t2ORRrr: 2177 case ARM::t2ORRri: 2178 case ARM::EORrr: 2179 case ARM::EORri: 2180 case ARM::t2EORrr: 2181 case ARM::t2EORri: { 2182 // Scan forward for the use of CPSR 2183 // When checking against MI: if it's a conditional code requires 2184 // checking of V bit, then this is not safe to do. 2185 // It is safe to remove CmpInstr if CPSR is redefined or killed. 2186 // If we are done with the basic block, we need to check whether CPSR is 2187 // live-out. 2188 SmallVector<std::pair<MachineOperand*, ARMCC::CondCodes>, 4> 2189 OperandsToUpdate; 2190 bool isSafe = false; 2191 I = CmpInstr; 2192 E = CmpInstr->getParent()->end(); 2193 while (!isSafe && ++I != E) { 2194 const MachineInstr &Instr = *I; 2195 for (unsigned IO = 0, EO = Instr.getNumOperands(); 2196 !isSafe && IO != EO; ++IO) { 2197 const MachineOperand &MO = Instr.getOperand(IO); 2198 if (MO.isRegMask() && MO.clobbersPhysReg(ARM::CPSR)) { 2199 isSafe = true; 2200 break; 2201 } 2202 if (!MO.isReg() || MO.getReg() != ARM::CPSR) 2203 continue; 2204 if (MO.isDef()) { 2205 isSafe = true; 2206 break; 2207 } 2208 // Condition code is after the operand before CPSR. 2209 ARMCC::CondCodes CC = (ARMCC::CondCodes)Instr.getOperand(IO-1).getImm(); 2210 if (Sub) { 2211 ARMCC::CondCodes NewCC = getSwappedCondition(CC); 2212 if (NewCC == ARMCC::AL) 2213 return false; 2214 // If we have SUB(r1, r2) and CMP(r2, r1), the condition code based 2215 // on CMP needs to be updated to be based on SUB. 2216 // Push the condition code operands to OperandsToUpdate. 2217 // If it is safe to remove CmpInstr, the condition code of these 2218 // operands will be modified. 2219 if (SrcReg2 != 0 && Sub->getOperand(1).getReg() == SrcReg2 && 2220 Sub->getOperand(2).getReg() == SrcReg) 2221 OperandsToUpdate.push_back(std::make_pair(&((*I).getOperand(IO-1)), 2222 NewCC)); 2223 } 2224 else 2225 switch (CC) { 2226 default: 2227 // CPSR can be used multiple times, we should continue. 2228 break; 2229 case ARMCC::VS: 2230 case ARMCC::VC: 2231 case ARMCC::GE: 2232 case ARMCC::LT: 2233 case ARMCC::GT: 2234 case ARMCC::LE: 2235 return false; 2236 } 2237 } 2238 } 2239 2240 // If CPSR is not killed nor re-defined, we should check whether it is 2241 // live-out. If it is live-out, do not optimize. 2242 if (!isSafe) { 2243 MachineBasicBlock *MBB = CmpInstr->getParent(); 2244 for (MachineBasicBlock::succ_iterator SI = MBB->succ_begin(), 2245 SE = MBB->succ_end(); SI != SE; ++SI) 2246 if ((*SI)->isLiveIn(ARM::CPSR)) 2247 return false; 2248 } 2249 2250 // Toggle the optional operand to CPSR. 2251 MI->getOperand(5).setReg(ARM::CPSR); 2252 MI->getOperand(5).setIsDef(true); 2253 assert(!isPredicated(MI) && "Can't use flags from predicated instruction"); 2254 CmpInstr->eraseFromParent(); 2255 2256 // Modify the condition code of operands in OperandsToUpdate. 2257 // Since we have SUB(r1, r2) and CMP(r2, r1), the condition code needs to 2258 // be changed from r2 > r1 to r1 < r2, from r2 < r1 to r1 > r2, etc. 2259 for (unsigned i = 0, e = OperandsToUpdate.size(); i < e; i++) 2260 OperandsToUpdate[i].first->setImm(OperandsToUpdate[i].second); 2261 return true; 2262 } 2263 } 2264 2265 return false; 2266 } 2267 2268 bool ARMBaseInstrInfo::FoldImmediate(MachineInstr *UseMI, 2269 MachineInstr *DefMI, unsigned Reg, 2270 MachineRegisterInfo *MRI) const { 2271 // Fold large immediates into add, sub, or, xor. 2272 unsigned DefOpc = DefMI->getOpcode(); 2273 if (DefOpc != ARM::t2MOVi32imm && DefOpc != ARM::MOVi32imm) 2274 return false; 2275 if (!DefMI->getOperand(1).isImm()) 2276 // Could be t2MOVi32imm <ga:xx> 2277 return false; 2278 2279 if (!MRI->hasOneNonDBGUse(Reg)) 2280 return false; 2281 2282 const MCInstrDesc &DefMCID = DefMI->getDesc(); 2283 if (DefMCID.hasOptionalDef()) { 2284 unsigned NumOps = DefMCID.getNumOperands(); 2285 const MachineOperand &MO = DefMI->getOperand(NumOps-1); 2286 if (MO.getReg() == ARM::CPSR && !MO.isDead()) 2287 // If DefMI defines CPSR and it is not dead, it's obviously not safe 2288 // to delete DefMI. 2289 return false; 2290 } 2291 2292 const MCInstrDesc &UseMCID = UseMI->getDesc(); 2293 if (UseMCID.hasOptionalDef()) { 2294 unsigned NumOps = UseMCID.getNumOperands(); 2295 if (UseMI->getOperand(NumOps-1).getReg() == ARM::CPSR) 2296 // If the instruction sets the flag, do not attempt this optimization 2297 // since it may change the semantics of the code. 2298 return false; 2299 } 2300 2301 unsigned UseOpc = UseMI->getOpcode(); 2302 unsigned NewUseOpc = 0; 2303 uint32_t ImmVal = (uint32_t)DefMI->getOperand(1).getImm(); 2304 uint32_t SOImmValV1 = 0, SOImmValV2 = 0; 2305 bool Commute = false; 2306 switch (UseOpc) { 2307 default: return false; 2308 case ARM::SUBrr: 2309 case ARM::ADDrr: 2310 case ARM::ORRrr: 2311 case ARM::EORrr: 2312 case ARM::t2SUBrr: 2313 case ARM::t2ADDrr: 2314 case ARM::t2ORRrr: 2315 case ARM::t2EORrr: { 2316 Commute = UseMI->getOperand(2).getReg() != Reg; 2317 switch (UseOpc) { 2318 default: break; 2319 case ARM::SUBrr: { 2320 if (Commute) 2321 return false; 2322 ImmVal = -ImmVal; 2323 NewUseOpc = ARM::SUBri; 2324 // Fallthrough 2325 } 2326 case ARM::ADDrr: 2327 case ARM::ORRrr: 2328 case ARM::EORrr: { 2329 if (!ARM_AM::isSOImmTwoPartVal(ImmVal)) 2330 return false; 2331 SOImmValV1 = (uint32_t)ARM_AM::getSOImmTwoPartFirst(ImmVal); 2332 SOImmValV2 = (uint32_t)ARM_AM::getSOImmTwoPartSecond(ImmVal); 2333 switch (UseOpc) { 2334 default: break; 2335 case ARM::ADDrr: NewUseOpc = ARM::ADDri; break; 2336 case ARM::ORRrr: NewUseOpc = ARM::ORRri; break; 2337 case ARM::EORrr: NewUseOpc = ARM::EORri; break; 2338 } 2339 break; 2340 } 2341 case ARM::t2SUBrr: { 2342 if (Commute) 2343 return false; 2344 ImmVal = -ImmVal; 2345 NewUseOpc = ARM::t2SUBri; 2346 // Fallthrough 2347 } 2348 case ARM::t2ADDrr: 2349 case ARM::t2ORRrr: 2350 case ARM::t2EORrr: { 2351 if (!ARM_AM::isT2SOImmTwoPartVal(ImmVal)) 2352 return false; 2353 SOImmValV1 = (uint32_t)ARM_AM::getT2SOImmTwoPartFirst(ImmVal); 2354 SOImmValV2 = (uint32_t)ARM_AM::getT2SOImmTwoPartSecond(ImmVal); 2355 switch (UseOpc) { 2356 default: break; 2357 case ARM::t2ADDrr: NewUseOpc = ARM::t2ADDri; break; 2358 case ARM::t2ORRrr: NewUseOpc = ARM::t2ORRri; break; 2359 case ARM::t2EORrr: NewUseOpc = ARM::t2EORri; break; 2360 } 2361 break; 2362 } 2363 } 2364 } 2365 } 2366 2367 unsigned OpIdx = Commute ? 2 : 1; 2368 unsigned Reg1 = UseMI->getOperand(OpIdx).getReg(); 2369 bool isKill = UseMI->getOperand(OpIdx).isKill(); 2370 unsigned NewReg = MRI->createVirtualRegister(MRI->getRegClass(Reg)); 2371 AddDefaultCC(AddDefaultPred(BuildMI(*UseMI->getParent(), 2372 UseMI, UseMI->getDebugLoc(), 2373 get(NewUseOpc), NewReg) 2374 .addReg(Reg1, getKillRegState(isKill)) 2375 .addImm(SOImmValV1))); 2376 UseMI->setDesc(get(NewUseOpc)); 2377 UseMI->getOperand(1).setReg(NewReg); 2378 UseMI->getOperand(1).setIsKill(); 2379 UseMI->getOperand(2).ChangeToImmediate(SOImmValV2); 2380 DefMI->eraseFromParent(); 2381 return true; 2382 } 2383 2384 static unsigned getNumMicroOpsSwiftLdSt(const InstrItineraryData *ItinData, 2385 const MachineInstr *MI) { 2386 switch (MI->getOpcode()) { 2387 default: { 2388 const MCInstrDesc &Desc = MI->getDesc(); 2389 int UOps = ItinData->getNumMicroOps(Desc.getSchedClass()); 2390 assert(UOps >= 0 && "bad # UOps"); 2391 return UOps; 2392 } 2393 2394 case ARM::LDRrs: 2395 case ARM::LDRBrs: 2396 case ARM::STRrs: 2397 case ARM::STRBrs: { 2398 unsigned ShOpVal = MI->getOperand(3).getImm(); 2399 bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub; 2400 unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); 2401 if (!isSub && 2402 (ShImm == 0 || 2403 ((ShImm == 1 || ShImm == 2 || ShImm == 3) && 2404 ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl))) 2405 return 1; 2406 return 2; 2407 } 2408 2409 case ARM::LDRH: 2410 case ARM::STRH: { 2411 if (!MI->getOperand(2).getReg()) 2412 return 1; 2413 2414 unsigned ShOpVal = MI->getOperand(3).getImm(); 2415 bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub; 2416 unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); 2417 if (!isSub && 2418 (ShImm == 0 || 2419 ((ShImm == 1 || ShImm == 2 || ShImm == 3) && 2420 ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl))) 2421 return 1; 2422 return 2; 2423 } 2424 2425 case ARM::LDRSB: 2426 case ARM::LDRSH: 2427 return (ARM_AM::getAM3Op(MI->getOperand(3).getImm()) == ARM_AM::sub) ? 3:2; 2428 2429 case ARM::LDRSB_POST: 2430 case ARM::LDRSH_POST: { 2431 unsigned Rt = MI->getOperand(0).getReg(); 2432 unsigned Rm = MI->getOperand(3).getReg(); 2433 return (Rt == Rm) ? 4 : 3; 2434 } 2435 2436 case ARM::LDR_PRE_REG: 2437 case ARM::LDRB_PRE_REG: { 2438 unsigned Rt = MI->getOperand(0).getReg(); 2439 unsigned Rm = MI->getOperand(3).getReg(); 2440 if (Rt == Rm) 2441 return 3; 2442 unsigned ShOpVal = MI->getOperand(4).getImm(); 2443 bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub; 2444 unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); 2445 if (!isSub && 2446 (ShImm == 0 || 2447 ((ShImm == 1 || ShImm == 2 || ShImm == 3) && 2448 ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl))) 2449 return 2; 2450 return 3; 2451 } 2452 2453 case ARM::STR_PRE_REG: 2454 case ARM::STRB_PRE_REG: { 2455 unsigned ShOpVal = MI->getOperand(4).getImm(); 2456 bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub; 2457 unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); 2458 if (!isSub && 2459 (ShImm == 0 || 2460 ((ShImm == 1 || ShImm == 2 || ShImm == 3) && 2461 ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl))) 2462 return 2; 2463 return 3; 2464 } 2465 2466 case ARM::LDRH_PRE: 2467 case ARM::STRH_PRE: { 2468 unsigned Rt = MI->getOperand(0).getReg(); 2469 unsigned Rm = MI->getOperand(3).getReg(); 2470 if (!Rm) 2471 return 2; 2472 if (Rt == Rm) 2473 return 3; 2474 return (ARM_AM::getAM3Op(MI->getOperand(4).getImm()) == ARM_AM::sub) 2475 ? 3 : 2; 2476 } 2477 2478 case ARM::LDR_POST_REG: 2479 case ARM::LDRB_POST_REG: 2480 case ARM::LDRH_POST: { 2481 unsigned Rt = MI->getOperand(0).getReg(); 2482 unsigned Rm = MI->getOperand(3).getReg(); 2483 return (Rt == Rm) ? 3 : 2; 2484 } 2485 2486 case ARM::LDR_PRE_IMM: 2487 case ARM::LDRB_PRE_IMM: 2488 case ARM::LDR_POST_IMM: 2489 case ARM::LDRB_POST_IMM: 2490 case ARM::STRB_POST_IMM: 2491 case ARM::STRB_POST_REG: 2492 case ARM::STRB_PRE_IMM: 2493 case ARM::STRH_POST: 2494 case ARM::STR_POST_IMM: 2495 case ARM::STR_POST_REG: 2496 case ARM::STR_PRE_IMM: 2497 return 2; 2498 2499 case ARM::LDRSB_PRE: 2500 case ARM::LDRSH_PRE: { 2501 unsigned Rm = MI->getOperand(3).getReg(); 2502 if (Rm == 0) 2503 return 3; 2504 unsigned Rt = MI->getOperand(0).getReg(); 2505 if (Rt == Rm) 2506 return 4; 2507 unsigned ShOpVal = MI->getOperand(4).getImm(); 2508 bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub; 2509 unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); 2510 if (!isSub && 2511 (ShImm == 0 || 2512 ((ShImm == 1 || ShImm == 2 || ShImm == 3) && 2513 ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl))) 2514 return 3; 2515 return 4; 2516 } 2517 2518 case ARM::LDRD: { 2519 unsigned Rt = MI->getOperand(0).getReg(); 2520 unsigned Rn = MI->getOperand(2).getReg(); 2521 unsigned Rm = MI->getOperand(3).getReg(); 2522 if (Rm) 2523 return (ARM_AM::getAM3Op(MI->getOperand(4).getImm()) == ARM_AM::sub) ?4:3; 2524 return (Rt == Rn) ? 3 : 2; 2525 } 2526 2527 case ARM::STRD: { 2528 unsigned Rm = MI->getOperand(3).getReg(); 2529 if (Rm) 2530 return (ARM_AM::getAM3Op(MI->getOperand(4).getImm()) == ARM_AM::sub) ?4:3; 2531 return 2; 2532 } 2533 2534 case ARM::LDRD_POST: 2535 case ARM::t2LDRD_POST: 2536 return 3; 2537 2538 case ARM::STRD_POST: 2539 case ARM::t2STRD_POST: 2540 return 4; 2541 2542 case ARM::LDRD_PRE: { 2543 unsigned Rt = MI->getOperand(0).getReg(); 2544 unsigned Rn = MI->getOperand(3).getReg(); 2545 unsigned Rm = MI->getOperand(4).getReg(); 2546 if (Rm) 2547 return (ARM_AM::getAM3Op(MI->getOperand(5).getImm()) == ARM_AM::sub) ?5:4; 2548 return (Rt == Rn) ? 4 : 3; 2549 } 2550 2551 case ARM::t2LDRD_PRE: { 2552 unsigned Rt = MI->getOperand(0).getReg(); 2553 unsigned Rn = MI->getOperand(3).getReg(); 2554 return (Rt == Rn) ? 4 : 3; 2555 } 2556 2557 case ARM::STRD_PRE: { 2558 unsigned Rm = MI->getOperand(4).getReg(); 2559 if (Rm) 2560 return (ARM_AM::getAM3Op(MI->getOperand(5).getImm()) == ARM_AM::sub) ?5:4; 2561 return 3; 2562 } 2563 2564 case ARM::t2STRD_PRE: 2565 return 3; 2566 2567 case ARM::t2LDR_POST: 2568 case ARM::t2LDRB_POST: 2569 case ARM::t2LDRB_PRE: 2570 case ARM::t2LDRSBi12: 2571 case ARM::t2LDRSBi8: 2572 case ARM::t2LDRSBpci: 2573 case ARM::t2LDRSBs: 2574 case ARM::t2LDRH_POST: 2575 case ARM::t2LDRH_PRE: 2576 case ARM::t2LDRSBT: 2577 case ARM::t2LDRSB_POST: 2578 case ARM::t2LDRSB_PRE: 2579 case ARM::t2LDRSH_POST: 2580 case ARM::t2LDRSH_PRE: 2581 case ARM::t2LDRSHi12: 2582 case ARM::t2LDRSHi8: 2583 case ARM::t2LDRSHpci: 2584 case ARM::t2LDRSHs: 2585 return 2; 2586 2587 case ARM::t2LDRDi8: { 2588 unsigned Rt = MI->getOperand(0).getReg(); 2589 unsigned Rn = MI->getOperand(2).getReg(); 2590 return (Rt == Rn) ? 3 : 2; 2591 } 2592 2593 case ARM::t2STRB_POST: 2594 case ARM::t2STRB_PRE: 2595 case ARM::t2STRBs: 2596 case ARM::t2STRDi8: 2597 case ARM::t2STRH_POST: 2598 case ARM::t2STRH_PRE: 2599 case ARM::t2STRHs: 2600 case ARM::t2STR_POST: 2601 case ARM::t2STR_PRE: 2602 case ARM::t2STRs: 2603 return 2; 2604 } 2605 } 2606 2607 // Return the number of 32-bit words loaded by LDM or stored by STM. If this 2608 // can't be easily determined return 0 (missing MachineMemOperand). 2609 // 2610 // FIXME: The current MachineInstr design does not support relying on machine 2611 // mem operands to determine the width of a memory access. Instead, we expect 2612 // the target to provide this information based on the instruction opcode and 2613 // operands. However, using MachineMemOperand is a the best solution now for 2614 // two reasons: 2615 // 2616 // 1) getNumMicroOps tries to infer LDM memory width from the total number of MI 2617 // operands. This is much more dangerous than using the MachineMemOperand 2618 // sizes because CodeGen passes can insert/remove optional machine operands. In 2619 // fact, it's totally incorrect for preRA passes and appears to be wrong for 2620 // postRA passes as well. 2621 // 2622 // 2) getNumLDMAddresses is only used by the scheduling machine model and any 2623 // machine model that calls this should handle the unknown (zero size) case. 2624 // 2625 // Long term, we should require a target hook that verifies MachineMemOperand 2626 // sizes during MC lowering. That target hook should be local to MC lowering 2627 // because we can't ensure that it is aware of other MI forms. Doing this will 2628 // ensure that MachineMemOperands are correctly propagated through all passes. 2629 unsigned ARMBaseInstrInfo::getNumLDMAddresses(const MachineInstr *MI) const { 2630 unsigned Size = 0; 2631 for (MachineInstr::mmo_iterator I = MI->memoperands_begin(), 2632 E = MI->memoperands_end(); I != E; ++I) { 2633 Size += (*I)->getSize(); 2634 } 2635 return Size / 4; 2636 } 2637 2638 unsigned 2639 ARMBaseInstrInfo::getNumMicroOps(const InstrItineraryData *ItinData, 2640 const MachineInstr *MI) const { 2641 if (!ItinData || ItinData->isEmpty()) 2642 return 1; 2643 2644 const MCInstrDesc &Desc = MI->getDesc(); 2645 unsigned Class = Desc.getSchedClass(); 2646 int ItinUOps = ItinData->getNumMicroOps(Class); 2647 if (ItinUOps >= 0) { 2648 if (Subtarget.isSwift() && (Desc.mayLoad() || Desc.mayStore())) 2649 return getNumMicroOpsSwiftLdSt(ItinData, MI); 2650 2651 return ItinUOps; 2652 } 2653 2654 unsigned Opc = MI->getOpcode(); 2655 switch (Opc) { 2656 default: 2657 llvm_unreachable("Unexpected multi-uops instruction!"); 2658 case ARM::VLDMQIA: 2659 case ARM::VSTMQIA: 2660 return 2; 2661 2662 // The number of uOps for load / store multiple are determined by the number 2663 // registers. 2664 // 2665 // On Cortex-A8, each pair of register loads / stores can be scheduled on the 2666 // same cycle. The scheduling for the first load / store must be done 2667 // separately by assuming the address is not 64-bit aligned. 2668 // 2669 // On Cortex-A9, the formula is simply (#reg / 2) + (#reg % 2). If the address 2670 // is not 64-bit aligned, then AGU would take an extra cycle. For VFP / NEON 2671 // load / store multiple, the formula is (#reg / 2) + (#reg % 2) + 1. 2672 case ARM::VLDMDIA: 2673 case ARM::VLDMDIA_UPD: 2674 case ARM::VLDMDDB_UPD: 2675 case ARM::VLDMSIA: 2676 case ARM::VLDMSIA_UPD: 2677 case ARM::VLDMSDB_UPD: 2678 case ARM::VSTMDIA: 2679 case ARM::VSTMDIA_UPD: 2680 case ARM::VSTMDDB_UPD: 2681 case ARM::VSTMSIA: 2682 case ARM::VSTMSIA_UPD: 2683 case ARM::VSTMSDB_UPD: { 2684 unsigned NumRegs = MI->getNumOperands() - Desc.getNumOperands(); 2685 return (NumRegs / 2) + (NumRegs % 2) + 1; 2686 } 2687 2688 case ARM::LDMIA_RET: 2689 case ARM::LDMIA: 2690 case ARM::LDMDA: 2691 case ARM::LDMDB: 2692 case ARM::LDMIB: 2693 case ARM::LDMIA_UPD: 2694 case ARM::LDMDA_UPD: 2695 case ARM::LDMDB_UPD: 2696 case ARM::LDMIB_UPD: 2697 case ARM::STMIA: 2698 case ARM::STMDA: 2699 case ARM::STMDB: 2700 case ARM::STMIB: 2701 case ARM::STMIA_UPD: 2702 case ARM::STMDA_UPD: 2703 case ARM::STMDB_UPD: 2704 case ARM::STMIB_UPD: 2705 case ARM::tLDMIA: 2706 case ARM::tLDMIA_UPD: 2707 case ARM::tSTMIA_UPD: 2708 case ARM::tPOP_RET: 2709 case ARM::tPOP: 2710 case ARM::tPUSH: 2711 case ARM::t2LDMIA_RET: 2712 case ARM::t2LDMIA: 2713 case ARM::t2LDMDB: 2714 case ARM::t2LDMIA_UPD: 2715 case ARM::t2LDMDB_UPD: 2716 case ARM::t2STMIA: 2717 case ARM::t2STMDB: 2718 case ARM::t2STMIA_UPD: 2719 case ARM::t2STMDB_UPD: { 2720 unsigned NumRegs = MI->getNumOperands() - Desc.getNumOperands() + 1; 2721 if (Subtarget.isSwift()) { 2722 int UOps = 1 + NumRegs; // One for address computation, one for each ld / st. 2723 switch (Opc) { 2724 default: break; 2725 case ARM::VLDMDIA_UPD: 2726 case ARM::VLDMDDB_UPD: 2727 case ARM::VLDMSIA_UPD: 2728 case ARM::VLDMSDB_UPD: 2729 case ARM::VSTMDIA_UPD: 2730 case ARM::VSTMDDB_UPD: 2731 case ARM::VSTMSIA_UPD: 2732 case ARM::VSTMSDB_UPD: 2733 case ARM::LDMIA_UPD: 2734 case ARM::LDMDA_UPD: 2735 case ARM::LDMDB_UPD: 2736 case ARM::LDMIB_UPD: 2737 case ARM::STMIA_UPD: 2738 case ARM::STMDA_UPD: 2739 case ARM::STMDB_UPD: 2740 case ARM::STMIB_UPD: 2741 case ARM::tLDMIA_UPD: 2742 case ARM::tSTMIA_UPD: 2743 case ARM::t2LDMIA_UPD: 2744 case ARM::t2LDMDB_UPD: 2745 case ARM::t2STMIA_UPD: 2746 case ARM::t2STMDB_UPD: 2747 ++UOps; // One for base register writeback. 2748 break; 2749 case ARM::LDMIA_RET: 2750 case ARM::tPOP_RET: 2751 case ARM::t2LDMIA_RET: 2752 UOps += 2; // One for base reg wb, one for write to pc. 2753 break; 2754 } 2755 return UOps; 2756 } else if (Subtarget.isCortexA8()) { 2757 if (NumRegs < 4) 2758 return 2; 2759 // 4 registers would be issued: 2, 2. 2760 // 5 registers would be issued: 2, 2, 1. 2761 int A8UOps = (NumRegs / 2); 2762 if (NumRegs % 2) 2763 ++A8UOps; 2764 return A8UOps; 2765 } else if (Subtarget.isLikeA9() || Subtarget.isSwift()) { 2766 int A9UOps = (NumRegs / 2); 2767 // If there are odd number of registers or if it's not 64-bit aligned, 2768 // then it takes an extra AGU (Address Generation Unit) cycle. 2769 if ((NumRegs % 2) || 2770 !MI->hasOneMemOperand() || 2771 (*MI->memoperands_begin())->getAlignment() < 8) 2772 ++A9UOps; 2773 return A9UOps; 2774 } else { 2775 // Assume the worst. 2776 return NumRegs; 2777 } 2778 } 2779 } 2780 } 2781 2782 int 2783 ARMBaseInstrInfo::getVLDMDefCycle(const InstrItineraryData *ItinData, 2784 const MCInstrDesc &DefMCID, 2785 unsigned DefClass, 2786 unsigned DefIdx, unsigned DefAlign) const { 2787 int RegNo = (int)(DefIdx+1) - DefMCID.getNumOperands() + 1; 2788 if (RegNo <= 0) 2789 // Def is the address writeback. 2790 return ItinData->getOperandCycle(DefClass, DefIdx); 2791 2792 int DefCycle; 2793 if (Subtarget.isCortexA8()) { 2794 // (regno / 2) + (regno % 2) + 1 2795 DefCycle = RegNo / 2 + 1; 2796 if (RegNo % 2) 2797 ++DefCycle; 2798 } else if (Subtarget.isLikeA9() || Subtarget.isSwift()) { 2799 DefCycle = RegNo; 2800 bool isSLoad = false; 2801 2802 switch (DefMCID.getOpcode()) { 2803 default: break; 2804 case ARM::VLDMSIA: 2805 case ARM::VLDMSIA_UPD: 2806 case ARM::VLDMSDB_UPD: 2807 isSLoad = true; 2808 break; 2809 } 2810 2811 // If there are odd number of 'S' registers or if it's not 64-bit aligned, 2812 // then it takes an extra cycle. 2813 if ((isSLoad && (RegNo % 2)) || DefAlign < 8) 2814 ++DefCycle; 2815 } else { 2816 // Assume the worst. 2817 DefCycle = RegNo + 2; 2818 } 2819 2820 return DefCycle; 2821 } 2822 2823 int 2824 ARMBaseInstrInfo::getLDMDefCycle(const InstrItineraryData *ItinData, 2825 const MCInstrDesc &DefMCID, 2826 unsigned DefClass, 2827 unsigned DefIdx, unsigned DefAlign) const { 2828 int RegNo = (int)(DefIdx+1) - DefMCID.getNumOperands() + 1; 2829 if (RegNo <= 0) 2830 // Def is the address writeback. 2831 return ItinData->getOperandCycle(DefClass, DefIdx); 2832 2833 int DefCycle; 2834 if (Subtarget.isCortexA8()) { 2835 // 4 registers would be issued: 1, 2, 1. 2836 // 5 registers would be issued: 1, 2, 2. 2837 DefCycle = RegNo / 2; 2838 if (DefCycle < 1) 2839 DefCycle = 1; 2840 // Result latency is issue cycle + 2: E2. 2841 DefCycle += 2; 2842 } else if (Subtarget.isLikeA9() || Subtarget.isSwift()) { 2843 DefCycle = (RegNo / 2); 2844 // If there are odd number of registers or if it's not 64-bit aligned, 2845 // then it takes an extra AGU (Address Generation Unit) cycle. 2846 if ((RegNo % 2) || DefAlign < 8) 2847 ++DefCycle; 2848 // Result latency is AGU cycles + 2. 2849 DefCycle += 2; 2850 } else { 2851 // Assume the worst. 2852 DefCycle = RegNo + 2; 2853 } 2854 2855 return DefCycle; 2856 } 2857 2858 int 2859 ARMBaseInstrInfo::getVSTMUseCycle(const InstrItineraryData *ItinData, 2860 const MCInstrDesc &UseMCID, 2861 unsigned UseClass, 2862 unsigned UseIdx, unsigned UseAlign) const { 2863 int RegNo = (int)(UseIdx+1) - UseMCID.getNumOperands() + 1; 2864 if (RegNo <= 0) 2865 return ItinData->getOperandCycle(UseClass, UseIdx); 2866 2867 int UseCycle; 2868 if (Subtarget.isCortexA8()) { 2869 // (regno / 2) + (regno % 2) + 1 2870 UseCycle = RegNo / 2 + 1; 2871 if (RegNo % 2) 2872 ++UseCycle; 2873 } else if (Subtarget.isLikeA9() || Subtarget.isSwift()) { 2874 UseCycle = RegNo; 2875 bool isSStore = false; 2876 2877 switch (UseMCID.getOpcode()) { 2878 default: break; 2879 case ARM::VSTMSIA: 2880 case ARM::VSTMSIA_UPD: 2881 case ARM::VSTMSDB_UPD: 2882 isSStore = true; 2883 break; 2884 } 2885 2886 // If there are odd number of 'S' registers or if it's not 64-bit aligned, 2887 // then it takes an extra cycle. 2888 if ((isSStore && (RegNo % 2)) || UseAlign < 8) 2889 ++UseCycle; 2890 } else { 2891 // Assume the worst. 2892 UseCycle = RegNo + 2; 2893 } 2894 2895 return UseCycle; 2896 } 2897 2898 int 2899 ARMBaseInstrInfo::getSTMUseCycle(const InstrItineraryData *ItinData, 2900 const MCInstrDesc &UseMCID, 2901 unsigned UseClass, 2902 unsigned UseIdx, unsigned UseAlign) const { 2903 int RegNo = (int)(UseIdx+1) - UseMCID.getNumOperands() + 1; 2904 if (RegNo <= 0) 2905 return ItinData->getOperandCycle(UseClass, UseIdx); 2906 2907 int UseCycle; 2908 if (Subtarget.isCortexA8()) { 2909 UseCycle = RegNo / 2; 2910 if (UseCycle < 2) 2911 UseCycle = 2; 2912 // Read in E3. 2913 UseCycle += 2; 2914 } else if (Subtarget.isLikeA9() || Subtarget.isSwift()) { 2915 UseCycle = (RegNo / 2); 2916 // If there are odd number of registers or if it's not 64-bit aligned, 2917 // then it takes an extra AGU (Address Generation Unit) cycle. 2918 if ((RegNo % 2) || UseAlign < 8) 2919 ++UseCycle; 2920 } else { 2921 // Assume the worst. 2922 UseCycle = 1; 2923 } 2924 return UseCycle; 2925 } 2926 2927 int 2928 ARMBaseInstrInfo::getOperandLatency(const InstrItineraryData *ItinData, 2929 const MCInstrDesc &DefMCID, 2930 unsigned DefIdx, unsigned DefAlign, 2931 const MCInstrDesc &UseMCID, 2932 unsigned UseIdx, unsigned UseAlign) const { 2933 unsigned DefClass = DefMCID.getSchedClass(); 2934 unsigned UseClass = UseMCID.getSchedClass(); 2935 2936 if (DefIdx < DefMCID.getNumDefs() && UseIdx < UseMCID.getNumOperands()) 2937 return ItinData->getOperandLatency(DefClass, DefIdx, UseClass, UseIdx); 2938 2939 // This may be a def / use of a variable_ops instruction, the operand 2940 // latency might be determinable dynamically. Let the target try to 2941 // figure it out. 2942 int DefCycle = -1; 2943 bool LdmBypass = false; 2944 switch (DefMCID.getOpcode()) { 2945 default: 2946 DefCycle = ItinData->getOperandCycle(DefClass, DefIdx); 2947 break; 2948 2949 case ARM::VLDMDIA: 2950 case ARM::VLDMDIA_UPD: 2951 case ARM::VLDMDDB_UPD: 2952 case ARM::VLDMSIA: 2953 case ARM::VLDMSIA_UPD: 2954 case ARM::VLDMSDB_UPD: 2955 DefCycle = getVLDMDefCycle(ItinData, DefMCID, DefClass, DefIdx, DefAlign); 2956 break; 2957 2958 case ARM::LDMIA_RET: 2959 case ARM::LDMIA: 2960 case ARM::LDMDA: 2961 case ARM::LDMDB: 2962 case ARM::LDMIB: 2963 case ARM::LDMIA_UPD: 2964 case ARM::LDMDA_UPD: 2965 case ARM::LDMDB_UPD: 2966 case ARM::LDMIB_UPD: 2967 case ARM::tLDMIA: 2968 case ARM::tLDMIA_UPD: 2969 case ARM::tPUSH: 2970 case ARM::t2LDMIA_RET: 2971 case ARM::t2LDMIA: 2972 case ARM::t2LDMDB: 2973 case ARM::t2LDMIA_UPD: 2974 case ARM::t2LDMDB_UPD: 2975 LdmBypass = 1; 2976 DefCycle = getLDMDefCycle(ItinData, DefMCID, DefClass, DefIdx, DefAlign); 2977 break; 2978 } 2979 2980 if (DefCycle == -1) 2981 // We can't seem to determine the result latency of the def, assume it's 2. 2982 DefCycle = 2; 2983 2984 int UseCycle = -1; 2985 switch (UseMCID.getOpcode()) { 2986 default: 2987 UseCycle = ItinData->getOperandCycle(UseClass, UseIdx); 2988 break; 2989 2990 case ARM::VSTMDIA: 2991 case ARM::VSTMDIA_UPD: 2992 case ARM::VSTMDDB_UPD: 2993 case ARM::VSTMSIA: 2994 case ARM::VSTMSIA_UPD: 2995 case ARM::VSTMSDB_UPD: 2996 UseCycle = getVSTMUseCycle(ItinData, UseMCID, UseClass, UseIdx, UseAlign); 2997 break; 2998 2999 case ARM::STMIA: 3000 case ARM::STMDA: 3001 case ARM::STMDB: 3002 case ARM::STMIB: 3003 case ARM::STMIA_UPD: 3004 case ARM::STMDA_UPD: 3005 case ARM::STMDB_UPD: 3006 case ARM::STMIB_UPD: 3007 case ARM::tSTMIA_UPD: 3008 case ARM::tPOP_RET: 3009 case ARM::tPOP: 3010 case ARM::t2STMIA: 3011 case ARM::t2STMDB: 3012 case ARM::t2STMIA_UPD: 3013 case ARM::t2STMDB_UPD: 3014 UseCycle = getSTMUseCycle(ItinData, UseMCID, UseClass, UseIdx, UseAlign); 3015 break; 3016 } 3017 3018 if (UseCycle == -1) 3019 // Assume it's read in the first stage. 3020 UseCycle = 1; 3021 3022 UseCycle = DefCycle - UseCycle + 1; 3023 if (UseCycle > 0) { 3024 if (LdmBypass) { 3025 // It's a variable_ops instruction so we can't use DefIdx here. Just use 3026 // first def operand. 3027 if (ItinData->hasPipelineForwarding(DefClass, DefMCID.getNumOperands()-1, 3028 UseClass, UseIdx)) 3029 --UseCycle; 3030 } else if (ItinData->hasPipelineForwarding(DefClass, DefIdx, 3031 UseClass, UseIdx)) { 3032 --UseCycle; 3033 } 3034 } 3035 3036 return UseCycle; 3037 } 3038 3039 static const MachineInstr *getBundledDefMI(const TargetRegisterInfo *TRI, 3040 const MachineInstr *MI, unsigned Reg, 3041 unsigned &DefIdx, unsigned &Dist) { 3042 Dist = 0; 3043 3044 MachineBasicBlock::const_iterator I = MI; ++I; 3045 MachineBasicBlock::const_instr_iterator II = 3046 llvm::prior(I.getInstrIterator()); 3047 assert(II->isInsideBundle() && "Empty bundle?"); 3048 3049 int Idx = -1; 3050 while (II->isInsideBundle()) { 3051 Idx = II->findRegisterDefOperandIdx(Reg, false, true, TRI); 3052 if (Idx != -1) 3053 break; 3054 --II; 3055 ++Dist; 3056 } 3057 3058 assert(Idx != -1 && "Cannot find bundled definition!"); 3059 DefIdx = Idx; 3060 return II; 3061 } 3062 3063 static const MachineInstr *getBundledUseMI(const TargetRegisterInfo *TRI, 3064 const MachineInstr *MI, unsigned Reg, 3065 unsigned &UseIdx, unsigned &Dist) { 3066 Dist = 0; 3067 3068 MachineBasicBlock::const_instr_iterator II = MI; ++II; 3069 assert(II->isInsideBundle() && "Empty bundle?"); 3070 MachineBasicBlock::const_instr_iterator E = MI->getParent()->instr_end(); 3071 3072 // FIXME: This doesn't properly handle multiple uses. 3073 int Idx = -1; 3074 while (II != E && II->isInsideBundle()) { 3075 Idx = II->findRegisterUseOperandIdx(Reg, false, TRI); 3076 if (Idx != -1) 3077 break; 3078 if (II->getOpcode() != ARM::t2IT) 3079 ++Dist; 3080 ++II; 3081 } 3082 3083 if (Idx == -1) { 3084 Dist = 0; 3085 return 0; 3086 } 3087 3088 UseIdx = Idx; 3089 return II; 3090 } 3091 3092 /// Return the number of cycles to add to (or subtract from) the static 3093 /// itinerary based on the def opcode and alignment. The caller will ensure that 3094 /// adjusted latency is at least one cycle. 3095 static int adjustDefLatency(const ARMSubtarget &Subtarget, 3096 const MachineInstr *DefMI, 3097 const MCInstrDesc *DefMCID, unsigned DefAlign) { 3098 int Adjust = 0; 3099 if (Subtarget.isCortexA8() || Subtarget.isLikeA9()) { 3100 // FIXME: Shifter op hack: no shift (i.e. [r +/- r]) or [r + r << 2] 3101 // variants are one cycle cheaper. 3102 switch (DefMCID->getOpcode()) { 3103 default: break; 3104 case ARM::LDRrs: 3105 case ARM::LDRBrs: { 3106 unsigned ShOpVal = DefMI->getOperand(3).getImm(); 3107 unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); 3108 if (ShImm == 0 || 3109 (ShImm == 2 && ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl)) 3110 --Adjust; 3111 break; 3112 } 3113 case ARM::t2LDRs: 3114 case ARM::t2LDRBs: 3115 case ARM::t2LDRHs: 3116 case ARM::t2LDRSHs: { 3117 // Thumb2 mode: lsl only. 3118 unsigned ShAmt = DefMI->getOperand(3).getImm(); 3119 if (ShAmt == 0 || ShAmt == 2) 3120 --Adjust; 3121 break; 3122 } 3123 } 3124 } else if (Subtarget.isSwift()) { 3125 // FIXME: Properly handle all of the latency adjustments for address 3126 // writeback. 3127 switch (DefMCID->getOpcode()) { 3128 default: break; 3129 case ARM::LDRrs: 3130 case ARM::LDRBrs: { 3131 unsigned ShOpVal = DefMI->getOperand(3).getImm(); 3132 bool isSub = ARM_AM::getAM2Op(ShOpVal) == ARM_AM::sub; 3133 unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); 3134 if (!isSub && 3135 (ShImm == 0 || 3136 ((ShImm == 1 || ShImm == 2 || ShImm == 3) && 3137 ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl))) 3138 Adjust -= 2; 3139 else if (!isSub && 3140 ShImm == 1 && ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsr) 3141 --Adjust; 3142 break; 3143 } 3144 case ARM::t2LDRs: 3145 case ARM::t2LDRBs: 3146 case ARM::t2LDRHs: 3147 case ARM::t2LDRSHs: { 3148 // Thumb2 mode: lsl only. 3149 unsigned ShAmt = DefMI->getOperand(3).getImm(); 3150 if (ShAmt == 0 || ShAmt == 1 || ShAmt == 2 || ShAmt == 3) 3151 Adjust -= 2; 3152 break; 3153 } 3154 } 3155 } 3156 3157 if (DefAlign < 8 && Subtarget.isLikeA9()) { 3158 switch (DefMCID->getOpcode()) { 3159 default: break; 3160 case ARM::VLD1q8: 3161 case ARM::VLD1q16: 3162 case ARM::VLD1q32: 3163 case ARM::VLD1q64: 3164 case ARM::VLD1q8wb_fixed: 3165 case ARM::VLD1q16wb_fixed: 3166 case ARM::VLD1q32wb_fixed: 3167 case ARM::VLD1q64wb_fixed: 3168 case ARM::VLD1q8wb_register: 3169 case ARM::VLD1q16wb_register: 3170 case ARM::VLD1q32wb_register: 3171 case ARM::VLD1q64wb_register: 3172 case ARM::VLD2d8: 3173 case ARM::VLD2d16: 3174 case ARM::VLD2d32: 3175 case ARM::VLD2q8: 3176 case ARM::VLD2q16: 3177 case ARM::VLD2q32: 3178 case ARM::VLD2d8wb_fixed: 3179 case ARM::VLD2d16wb_fixed: 3180 case ARM::VLD2d32wb_fixed: 3181 case ARM::VLD2q8wb_fixed: 3182 case ARM::VLD2q16wb_fixed: 3183 case ARM::VLD2q32wb_fixed: 3184 case ARM::VLD2d8wb_register: 3185 case ARM::VLD2d16wb_register: 3186 case ARM::VLD2d32wb_register: 3187 case ARM::VLD2q8wb_register: 3188 case ARM::VLD2q16wb_register: 3189 case ARM::VLD2q32wb_register: 3190 case ARM::VLD3d8: 3191 case ARM::VLD3d16: 3192 case ARM::VLD3d32: 3193 case ARM::VLD1d64T: 3194 case ARM::VLD3d8_UPD: 3195 case ARM::VLD3d16_UPD: 3196 case ARM::VLD3d32_UPD: 3197 case ARM::VLD1d64Twb_fixed: 3198 case ARM::VLD1d64Twb_register: 3199 case ARM::VLD3q8_UPD: 3200 case ARM::VLD3q16_UPD: 3201 case ARM::VLD3q32_UPD: 3202 case ARM::VLD4d8: 3203 case ARM::VLD4d16: 3204 case ARM::VLD4d32: 3205 case ARM::VLD1d64Q: 3206 case ARM::VLD4d8_UPD: 3207 case ARM::VLD4d16_UPD: 3208 case ARM::VLD4d32_UPD: 3209 case ARM::VLD1d64Qwb_fixed: 3210 case ARM::VLD1d64Qwb_register: 3211 case ARM::VLD4q8_UPD: 3212 case ARM::VLD4q16_UPD: 3213 case ARM::VLD4q32_UPD: 3214 case ARM::VLD1DUPq8: 3215 case ARM::VLD1DUPq16: 3216 case ARM::VLD1DUPq32: 3217 case ARM::VLD1DUPq8wb_fixed: 3218 case ARM::VLD1DUPq16wb_fixed: 3219 case ARM::VLD1DUPq32wb_fixed: 3220 case ARM::VLD1DUPq8wb_register: 3221 case ARM::VLD1DUPq16wb_register: 3222 case ARM::VLD1DUPq32wb_register: 3223 case ARM::VLD2DUPd8: 3224 case ARM::VLD2DUPd16: 3225 case ARM::VLD2DUPd32: 3226 case ARM::VLD2DUPd8wb_fixed: 3227 case ARM::VLD2DUPd16wb_fixed: 3228 case ARM::VLD2DUPd32wb_fixed: 3229 case ARM::VLD2DUPd8wb_register: 3230 case ARM::VLD2DUPd16wb_register: 3231 case ARM::VLD2DUPd32wb_register: 3232 case ARM::VLD4DUPd8: 3233 case ARM::VLD4DUPd16: 3234 case ARM::VLD4DUPd32: 3235 case ARM::VLD4DUPd8_UPD: 3236 case ARM::VLD4DUPd16_UPD: 3237 case ARM::VLD4DUPd32_UPD: 3238 case ARM::VLD1LNd8: 3239 case ARM::VLD1LNd16: 3240 case ARM::VLD1LNd32: 3241 case ARM::VLD1LNd8_UPD: 3242 case ARM::VLD1LNd16_UPD: 3243 case ARM::VLD1LNd32_UPD: 3244 case ARM::VLD2LNd8: 3245 case ARM::VLD2LNd16: 3246 case ARM::VLD2LNd32: 3247 case ARM::VLD2LNq16: 3248 case ARM::VLD2LNq32: 3249 case ARM::VLD2LNd8_UPD: 3250 case ARM::VLD2LNd16_UPD: 3251 case ARM::VLD2LNd32_UPD: 3252 case ARM::VLD2LNq16_UPD: 3253 case ARM::VLD2LNq32_UPD: 3254 case ARM::VLD4LNd8: 3255 case ARM::VLD4LNd16: 3256 case ARM::VLD4LNd32: 3257 case ARM::VLD4LNq16: 3258 case ARM::VLD4LNq32: 3259 case ARM::VLD4LNd8_UPD: 3260 case ARM::VLD4LNd16_UPD: 3261 case ARM::VLD4LNd32_UPD: 3262 case ARM::VLD4LNq16_UPD: 3263 case ARM::VLD4LNq32_UPD: 3264 // If the address is not 64-bit aligned, the latencies of these 3265 // instructions increases by one. 3266 ++Adjust; 3267 break; 3268 } 3269 } 3270 return Adjust; 3271 } 3272 3273 3274 3275 int 3276 ARMBaseInstrInfo::getOperandLatency(const InstrItineraryData *ItinData, 3277 const MachineInstr *DefMI, unsigned DefIdx, 3278 const MachineInstr *UseMI, 3279 unsigned UseIdx) const { 3280 // No operand latency. The caller may fall back to getInstrLatency. 3281 if (!ItinData || ItinData->isEmpty()) 3282 return -1; 3283 3284 const MachineOperand &DefMO = DefMI->getOperand(DefIdx); 3285 unsigned Reg = DefMO.getReg(); 3286 const MCInstrDesc *DefMCID = &DefMI->getDesc(); 3287 const MCInstrDesc *UseMCID = &UseMI->getDesc(); 3288 3289 unsigned DefAdj = 0; 3290 if (DefMI->isBundle()) { 3291 DefMI = getBundledDefMI(&getRegisterInfo(), DefMI, Reg, DefIdx, DefAdj); 3292 DefMCID = &DefMI->getDesc(); 3293 } 3294 if (DefMI->isCopyLike() || DefMI->isInsertSubreg() || 3295 DefMI->isRegSequence() || DefMI->isImplicitDef()) { 3296 return 1; 3297 } 3298 3299 unsigned UseAdj = 0; 3300 if (UseMI->isBundle()) { 3301 unsigned NewUseIdx; 3302 const MachineInstr *NewUseMI = getBundledUseMI(&getRegisterInfo(), UseMI, 3303 Reg, NewUseIdx, UseAdj); 3304 if (!NewUseMI) 3305 return -1; 3306 3307 UseMI = NewUseMI; 3308 UseIdx = NewUseIdx; 3309 UseMCID = &UseMI->getDesc(); 3310 } 3311 3312 if (Reg == ARM::CPSR) { 3313 if (DefMI->getOpcode() == ARM::FMSTAT) { 3314 // fpscr -> cpsr stalls over 20 cycles on A8 (and earlier?) 3315 return Subtarget.isLikeA9() ? 1 : 20; 3316 } 3317 3318 // CPSR set and branch can be paired in the same cycle. 3319 if (UseMI->isBranch()) 3320 return 0; 3321 3322 // Otherwise it takes the instruction latency (generally one). 3323 unsigned Latency = getInstrLatency(ItinData, DefMI); 3324 3325 // For Thumb2 and -Os, prefer scheduling CPSR setting instruction close to 3326 // its uses. Instructions which are otherwise scheduled between them may 3327 // incur a code size penalty (not able to use the CPSR setting 16-bit 3328 // instructions). 3329 if (Latency > 0 && Subtarget.isThumb2()) { 3330 const MachineFunction *MF = DefMI->getParent()->getParent(); 3331 if (MF->getFunction()->getAttributes(). 3332 hasAttribute(AttributeSet::FunctionIndex, 3333 Attribute::OptimizeForSize)) 3334 --Latency; 3335 } 3336 return Latency; 3337 } 3338 3339 if (DefMO.isImplicit() || UseMI->getOperand(UseIdx).isImplicit()) 3340 return -1; 3341 3342 unsigned DefAlign = DefMI->hasOneMemOperand() 3343 ? (*DefMI->memoperands_begin())->getAlignment() : 0; 3344 unsigned UseAlign = UseMI->hasOneMemOperand() 3345 ? (*UseMI->memoperands_begin())->getAlignment() : 0; 3346 3347 // Get the itinerary's latency if possible, and handle variable_ops. 3348 int Latency = getOperandLatency(ItinData, *DefMCID, DefIdx, DefAlign, 3349 *UseMCID, UseIdx, UseAlign); 3350 // Unable to find operand latency. The caller may resort to getInstrLatency. 3351 if (Latency < 0) 3352 return Latency; 3353 3354 // Adjust for IT block position. 3355 int Adj = DefAdj + UseAdj; 3356 3357 // Adjust for dynamic def-side opcode variants not captured by the itinerary. 3358 Adj += adjustDefLatency(Subtarget, DefMI, DefMCID, DefAlign); 3359 if (Adj >= 0 || (int)Latency > -Adj) { 3360 return Latency + Adj; 3361 } 3362 // Return the itinerary latency, which may be zero but not less than zero. 3363 return Latency; 3364 } 3365 3366 int 3367 ARMBaseInstrInfo::getOperandLatency(const InstrItineraryData *ItinData, 3368 SDNode *DefNode, unsigned DefIdx, 3369 SDNode *UseNode, unsigned UseIdx) const { 3370 if (!DefNode->isMachineOpcode()) 3371 return 1; 3372 3373 const MCInstrDesc &DefMCID = get(DefNode->getMachineOpcode()); 3374 3375 if (isZeroCost(DefMCID.Opcode)) 3376 return 0; 3377 3378 if (!ItinData || ItinData->isEmpty()) 3379 return DefMCID.mayLoad() ? 3 : 1; 3380 3381 if (!UseNode->isMachineOpcode()) { 3382 int Latency = ItinData->getOperandCycle(DefMCID.getSchedClass(), DefIdx); 3383 if (Subtarget.isLikeA9() || Subtarget.isSwift()) 3384 return Latency <= 2 ? 1 : Latency - 1; 3385 else 3386 return Latency <= 3 ? 1 : Latency - 2; 3387 } 3388 3389 const MCInstrDesc &UseMCID = get(UseNode->getMachineOpcode()); 3390 const MachineSDNode *DefMN = dyn_cast<MachineSDNode>(DefNode); 3391 unsigned DefAlign = !DefMN->memoperands_empty() 3392 ? (*DefMN->memoperands_begin())->getAlignment() : 0; 3393 const MachineSDNode *UseMN = dyn_cast<MachineSDNode>(UseNode); 3394 unsigned UseAlign = !UseMN->memoperands_empty() 3395 ? (*UseMN->memoperands_begin())->getAlignment() : 0; 3396 int Latency = getOperandLatency(ItinData, DefMCID, DefIdx, DefAlign, 3397 UseMCID, UseIdx, UseAlign); 3398 3399 if (Latency > 1 && 3400 (Subtarget.isCortexA8() || Subtarget.isLikeA9())) { 3401 // FIXME: Shifter op hack: no shift (i.e. [r +/- r]) or [r + r << 2] 3402 // variants are one cycle cheaper. 3403 switch (DefMCID.getOpcode()) { 3404 default: break; 3405 case ARM::LDRrs: 3406 case ARM::LDRBrs: { 3407 unsigned ShOpVal = 3408 cast<ConstantSDNode>(DefNode->getOperand(2))->getZExtValue(); 3409 unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); 3410 if (ShImm == 0 || 3411 (ShImm == 2 && ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl)) 3412 --Latency; 3413 break; 3414 } 3415 case ARM::t2LDRs: 3416 case ARM::t2LDRBs: 3417 case ARM::t2LDRHs: 3418 case ARM::t2LDRSHs: { 3419 // Thumb2 mode: lsl only. 3420 unsigned ShAmt = 3421 cast<ConstantSDNode>(DefNode->getOperand(2))->getZExtValue(); 3422 if (ShAmt == 0 || ShAmt == 2) 3423 --Latency; 3424 break; 3425 } 3426 } 3427 } else if (DefIdx == 0 && Latency > 2 && Subtarget.isSwift()) { 3428 // FIXME: Properly handle all of the latency adjustments for address 3429 // writeback. 3430 switch (DefMCID.getOpcode()) { 3431 default: break; 3432 case ARM::LDRrs: 3433 case ARM::LDRBrs: { 3434 unsigned ShOpVal = 3435 cast<ConstantSDNode>(DefNode->getOperand(2))->getZExtValue(); 3436 unsigned ShImm = ARM_AM::getAM2Offset(ShOpVal); 3437 if (ShImm == 0 || 3438 ((ShImm == 1 || ShImm == 2 || ShImm == 3) && 3439 ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsl)) 3440 Latency -= 2; 3441 else if (ShImm == 1 && ARM_AM::getAM2ShiftOpc(ShOpVal) == ARM_AM::lsr) 3442 --Latency; 3443 break; 3444 } 3445 case ARM::t2LDRs: 3446 case ARM::t2LDRBs: 3447 case ARM::t2LDRHs: 3448 case ARM::t2LDRSHs: { 3449 // Thumb2 mode: lsl 0-3 only. 3450 Latency -= 2; 3451 break; 3452 } 3453 } 3454 } 3455 3456 if (DefAlign < 8 && Subtarget.isLikeA9()) 3457 switch (DefMCID.getOpcode()) { 3458 default: break; 3459 case ARM::VLD1q8: 3460 case ARM::VLD1q16: 3461 case ARM::VLD1q32: 3462 case ARM::VLD1q64: 3463 case ARM::VLD1q8wb_register: 3464 case ARM::VLD1q16wb_register: 3465 case ARM::VLD1q32wb_register: 3466 case ARM::VLD1q64wb_register: 3467 case ARM::VLD1q8wb_fixed: 3468 case ARM::VLD1q16wb_fixed: 3469 case ARM::VLD1q32wb_fixed: 3470 case ARM::VLD1q64wb_fixed: 3471 case ARM::VLD2d8: 3472 case ARM::VLD2d16: 3473 case ARM::VLD2d32: 3474 case ARM::VLD2q8Pseudo: 3475 case ARM::VLD2q16Pseudo: 3476 case ARM::VLD2q32Pseudo: 3477 case ARM::VLD2d8wb_fixed: 3478 case ARM::VLD2d16wb_fixed: 3479 case ARM::VLD2d32wb_fixed: 3480 case ARM::VLD2q8PseudoWB_fixed: 3481 case ARM::VLD2q16PseudoWB_fixed: 3482 case ARM::VLD2q32PseudoWB_fixed: 3483 case ARM::VLD2d8wb_register: 3484 case ARM::VLD2d16wb_register: 3485 case ARM::VLD2d32wb_register: 3486 case ARM::VLD2q8PseudoWB_register: 3487 case ARM::VLD2q16PseudoWB_register: 3488 case ARM::VLD2q32PseudoWB_register: 3489 case ARM::VLD3d8Pseudo: 3490 case ARM::VLD3d16Pseudo: 3491 case ARM::VLD3d32Pseudo: 3492 case ARM::VLD1d64TPseudo: 3493 case ARM::VLD3d8Pseudo_UPD: 3494 case ARM::VLD3d16Pseudo_UPD: 3495 case ARM::VLD3d32Pseudo_UPD: 3496 case ARM::VLD3q8Pseudo_UPD: 3497 case ARM::VLD3q16Pseudo_UPD: 3498 case ARM::VLD3q32Pseudo_UPD: 3499 case ARM::VLD3q8oddPseudo: 3500 case ARM::VLD3q16oddPseudo: 3501 case ARM::VLD3q32oddPseudo: 3502 case ARM::VLD3q8oddPseudo_UPD: 3503 case ARM::VLD3q16oddPseudo_UPD: 3504 case ARM::VLD3q32oddPseudo_UPD: 3505 case ARM::VLD4d8Pseudo: 3506 case ARM::VLD4d16Pseudo: 3507 case ARM::VLD4d32Pseudo: 3508 case ARM::VLD1d64QPseudo: 3509 case ARM::VLD4d8Pseudo_UPD: 3510 case ARM::VLD4d16Pseudo_UPD: 3511 case ARM::VLD4d32Pseudo_UPD: 3512 case ARM::VLD4q8Pseudo_UPD: 3513 case ARM::VLD4q16Pseudo_UPD: 3514 case ARM::VLD4q32Pseudo_UPD: 3515 case ARM::VLD4q8oddPseudo: 3516 case ARM::VLD4q16oddPseudo: 3517 case ARM::VLD4q32oddPseudo: 3518 case ARM::VLD4q8oddPseudo_UPD: 3519 case ARM::VLD4q16oddPseudo_UPD: 3520 case ARM::VLD4q32oddPseudo_UPD: 3521 case ARM::VLD1DUPq8: 3522 case ARM::VLD1DUPq16: 3523 case ARM::VLD1DUPq32: 3524 case ARM::VLD1DUPq8wb_fixed: 3525 case ARM::VLD1DUPq16wb_fixed: 3526 case ARM::VLD1DUPq32wb_fixed: 3527 case ARM::VLD1DUPq8wb_register: 3528 case ARM::VLD1DUPq16wb_register: 3529 case ARM::VLD1DUPq32wb_register: 3530 case ARM::VLD2DUPd8: 3531 case ARM::VLD2DUPd16: 3532 case ARM::VLD2DUPd32: 3533 case ARM::VLD2DUPd8wb_fixed: 3534 case ARM::VLD2DUPd16wb_fixed: 3535 case ARM::VLD2DUPd32wb_fixed: 3536 case ARM::VLD2DUPd8wb_register: 3537 case ARM::VLD2DUPd16wb_register: 3538 case ARM::VLD2DUPd32wb_register: 3539 case ARM::VLD4DUPd8Pseudo: 3540 case ARM::VLD4DUPd16Pseudo: 3541 case ARM::VLD4DUPd32Pseudo: 3542 case ARM::VLD4DUPd8Pseudo_UPD: 3543 case ARM::VLD4DUPd16Pseudo_UPD: 3544 case ARM::VLD4DUPd32Pseudo_UPD: 3545 case ARM::VLD1LNq8Pseudo: 3546 case ARM::VLD1LNq16Pseudo: 3547 case ARM::VLD1LNq32Pseudo: 3548 case ARM::VLD1LNq8Pseudo_UPD: 3549 case ARM::VLD1LNq16Pseudo_UPD: 3550 case ARM::VLD1LNq32Pseudo_UPD: 3551 case ARM::VLD2LNd8Pseudo: 3552 case ARM::VLD2LNd16Pseudo: 3553 case ARM::VLD2LNd32Pseudo: 3554 case ARM::VLD2LNq16Pseudo: 3555 case ARM::VLD2LNq32Pseudo: 3556 case ARM::VLD2LNd8Pseudo_UPD: 3557 case ARM::VLD2LNd16Pseudo_UPD: 3558 case ARM::VLD2LNd32Pseudo_UPD: 3559 case ARM::VLD2LNq16Pseudo_UPD: 3560 case ARM::VLD2LNq32Pseudo_UPD: 3561 case ARM::VLD4LNd8Pseudo: 3562 case ARM::VLD4LNd16Pseudo: 3563 case ARM::VLD4LNd32Pseudo: 3564 case ARM::VLD4LNq16Pseudo: 3565 case ARM::VLD4LNq32Pseudo: 3566 case ARM::VLD4LNd8Pseudo_UPD: 3567 case ARM::VLD4LNd16Pseudo_UPD: 3568 case ARM::VLD4LNd32Pseudo_UPD: 3569 case ARM::VLD4LNq16Pseudo_UPD: 3570 case ARM::VLD4LNq32Pseudo_UPD: 3571 // If the address is not 64-bit aligned, the latencies of these 3572 // instructions increases by one. 3573 ++Latency; 3574 break; 3575 } 3576 3577 return Latency; 3578 } 3579 3580 unsigned ARMBaseInstrInfo::getInstrLatency(const InstrItineraryData *ItinData, 3581 const MachineInstr *MI, 3582 unsigned *PredCost) const { 3583 if (MI->isCopyLike() || MI->isInsertSubreg() || 3584 MI->isRegSequence() || MI->isImplicitDef()) 3585 return 1; 3586 3587 // An instruction scheduler typically runs on unbundled instructions, however 3588 // other passes may query the latency of a bundled instruction. 3589 if (MI->isBundle()) { 3590 unsigned Latency = 0; 3591 MachineBasicBlock::const_instr_iterator I = MI; 3592 MachineBasicBlock::const_instr_iterator E = MI->getParent()->instr_end(); 3593 while (++I != E && I->isInsideBundle()) { 3594 if (I->getOpcode() != ARM::t2IT) 3595 Latency += getInstrLatency(ItinData, I, PredCost); 3596 } 3597 return Latency; 3598 } 3599 3600 const MCInstrDesc &MCID = MI->getDesc(); 3601 if (PredCost && (MCID.isCall() || MCID.hasImplicitDefOfPhysReg(ARM::CPSR))) { 3602 // When predicated, CPSR is an additional source operand for CPSR updating 3603 // instructions, this apparently increases their latencies. 3604 *PredCost = 1; 3605 } 3606 // Be sure to call getStageLatency for an empty itinerary in case it has a 3607 // valid MinLatency property. 3608 if (!ItinData) 3609 return MI->mayLoad() ? 3 : 1; 3610 3611 unsigned Class = MCID.getSchedClass(); 3612 3613 // For instructions with variable uops, use uops as latency. 3614 if (!ItinData->isEmpty() && ItinData->getNumMicroOps(Class) < 0) 3615 return getNumMicroOps(ItinData, MI); 3616 3617 // For the common case, fall back on the itinerary's latency. 3618 unsigned Latency = ItinData->getStageLatency(Class); 3619 3620 // Adjust for dynamic def-side opcode variants not captured by the itinerary. 3621 unsigned DefAlign = MI->hasOneMemOperand() 3622 ? (*MI->memoperands_begin())->getAlignment() : 0; 3623 int Adj = adjustDefLatency(Subtarget, MI, &MCID, DefAlign); 3624 if (Adj >= 0 || (int)Latency > -Adj) { 3625 return Latency + Adj; 3626 } 3627 return Latency; 3628 } 3629 3630 int ARMBaseInstrInfo::getInstrLatency(const InstrItineraryData *ItinData, 3631 SDNode *Node) const { 3632 if (!Node->isMachineOpcode()) 3633 return 1; 3634 3635 if (!ItinData || ItinData->isEmpty()) 3636 return 1; 3637 3638 unsigned Opcode = Node->getMachineOpcode(); 3639 switch (Opcode) { 3640 default: 3641 return ItinData->getStageLatency(get(Opcode).getSchedClass()); 3642 case ARM::VLDMQIA: 3643 case ARM::VSTMQIA: 3644 return 2; 3645 } 3646 } 3647 3648 bool ARMBaseInstrInfo:: 3649 hasHighOperandLatency(const InstrItineraryData *ItinData, 3650 const MachineRegisterInfo *MRI, 3651 const MachineInstr *DefMI, unsigned DefIdx, 3652 const MachineInstr *UseMI, unsigned UseIdx) const { 3653 unsigned DDomain = DefMI->getDesc().TSFlags & ARMII::DomainMask; 3654 unsigned UDomain = UseMI->getDesc().TSFlags & ARMII::DomainMask; 3655 if (Subtarget.isCortexA8() && 3656 (DDomain == ARMII::DomainVFP || UDomain == ARMII::DomainVFP)) 3657 // CortexA8 VFP instructions are not pipelined. 3658 return true; 3659 3660 // Hoist VFP / NEON instructions with 4 or higher latency. 3661 int Latency = computeOperandLatency(ItinData, DefMI, DefIdx, UseMI, UseIdx, 3662 /*FindMin=*/false); 3663 if (Latency < 0) 3664 Latency = getInstrLatency(ItinData, DefMI); 3665 if (Latency <= 3) 3666 return false; 3667 return DDomain == ARMII::DomainVFP || DDomain == ARMII::DomainNEON || 3668 UDomain == ARMII::DomainVFP || UDomain == ARMII::DomainNEON; 3669 } 3670 3671 bool ARMBaseInstrInfo:: 3672 hasLowDefLatency(const InstrItineraryData *ItinData, 3673 const MachineInstr *DefMI, unsigned DefIdx) const { 3674 if (!ItinData || ItinData->isEmpty()) 3675 return false; 3676 3677 unsigned DDomain = DefMI->getDesc().TSFlags & ARMII::DomainMask; 3678 if (DDomain == ARMII::DomainGeneral) { 3679 unsigned DefClass = DefMI->getDesc().getSchedClass(); 3680 int DefCycle = ItinData->getOperandCycle(DefClass, DefIdx); 3681 return (DefCycle != -1 && DefCycle <= 2); 3682 } 3683 return false; 3684 } 3685 3686 bool ARMBaseInstrInfo::verifyInstruction(const MachineInstr *MI, 3687 StringRef &ErrInfo) const { 3688 if (convertAddSubFlagsOpcode(MI->getOpcode())) { 3689 ErrInfo = "Pseudo flag setting opcodes only exist in Selection DAG"; 3690 return false; 3691 } 3692 return true; 3693 } 3694 3695 bool 3696 ARMBaseInstrInfo::isFpMLxInstruction(unsigned Opcode, unsigned &MulOpc, 3697 unsigned &AddSubOpc, 3698 bool &NegAcc, bool &HasLane) const { 3699 DenseMap<unsigned, unsigned>::const_iterator I = MLxEntryMap.find(Opcode); 3700 if (I == MLxEntryMap.end()) 3701 return false; 3702 3703 const ARM_MLxEntry &Entry = ARM_MLxTable[I->second]; 3704 MulOpc = Entry.MulOpc; 3705 AddSubOpc = Entry.AddSubOpc; 3706 NegAcc = Entry.NegAcc; 3707 HasLane = Entry.HasLane; 3708 return true; 3709 } 3710 3711 //===----------------------------------------------------------------------===// 3712 // Execution domains. 3713 //===----------------------------------------------------------------------===// 3714 // 3715 // Some instructions go down the NEON pipeline, some go down the VFP pipeline, 3716 // and some can go down both. The vmov instructions go down the VFP pipeline, 3717 // but they can be changed to vorr equivalents that are executed by the NEON 3718 // pipeline. 3719 // 3720 // We use the following execution domain numbering: 3721 // 3722 enum ARMExeDomain { 3723 ExeGeneric = 0, 3724 ExeVFP = 1, 3725 ExeNEON = 2 3726 }; 3727 // 3728 // Also see ARMInstrFormats.td and Domain* enums in ARMBaseInfo.h 3729 // 3730 std::pair<uint16_t, uint16_t> 3731 ARMBaseInstrInfo::getExecutionDomain(const MachineInstr *MI) const { 3732 // VMOVD, VMOVRS and VMOVSR are VFP instructions, but can be changed to NEON 3733 // if they are not predicated. 3734 if (MI->getOpcode() == ARM::VMOVD && !isPredicated(MI)) 3735 return std::make_pair(ExeVFP, (1<<ExeVFP) | (1<<ExeNEON)); 3736 3737 // A9-like cores are particularly picky about mixing the two and want these 3738 // converted. 3739 if (Subtarget.isLikeA9() && !isPredicated(MI) && 3740 (MI->getOpcode() == ARM::VMOVRS || 3741 MI->getOpcode() == ARM::VMOVSR || 3742 MI->getOpcode() == ARM::VMOVS)) 3743 return std::make_pair(ExeVFP, (1<<ExeVFP) | (1<<ExeNEON)); 3744 3745 // No other instructions can be swizzled, so just determine their domain. 3746 unsigned Domain = MI->getDesc().TSFlags & ARMII::DomainMask; 3747 3748 if (Domain & ARMII::DomainNEON) 3749 return std::make_pair(ExeNEON, 0); 3750 3751 // Certain instructions can go either way on Cortex-A8. 3752 // Treat them as NEON instructions. 3753 if ((Domain & ARMII::DomainNEONA8) && Subtarget.isCortexA8()) 3754 return std::make_pair(ExeNEON, 0); 3755 3756 if (Domain & ARMII::DomainVFP) 3757 return std::make_pair(ExeVFP, 0); 3758 3759 return std::make_pair(ExeGeneric, 0); 3760 } 3761 3762 static unsigned getCorrespondingDRegAndLane(const TargetRegisterInfo *TRI, 3763 unsigned SReg, unsigned &Lane) { 3764 unsigned DReg = TRI->getMatchingSuperReg(SReg, ARM::ssub_0, &ARM::DPRRegClass); 3765 Lane = 0; 3766 3767 if (DReg != ARM::NoRegister) 3768 return DReg; 3769 3770 Lane = 1; 3771 DReg = TRI->getMatchingSuperReg(SReg, ARM::ssub_1, &ARM::DPRRegClass); 3772 3773 assert(DReg && "S-register with no D super-register?"); 3774 return DReg; 3775 } 3776 3777 /// getImplicitSPRUseForDPRUse - Given a use of a DPR register and lane, 3778 /// set ImplicitSReg to a register number that must be marked as implicit-use or 3779 /// zero if no register needs to be defined as implicit-use. 3780 /// 3781 /// If the function cannot determine if an SPR should be marked implicit use or 3782 /// not, it returns false. 3783 /// 3784 /// This function handles cases where an instruction is being modified from taking 3785 /// an SPR to a DPR[Lane]. A use of the DPR is being added, which may conflict 3786 /// with an earlier def of an SPR corresponding to DPR[Lane^1] (i.e. the other 3787 /// lane of the DPR). 3788 /// 3789 /// If the other SPR is defined, an implicit-use of it should be added. Else, 3790 /// (including the case where the DPR itself is defined), it should not. 3791 /// 3792 static bool getImplicitSPRUseForDPRUse(const TargetRegisterInfo *TRI, 3793 MachineInstr *MI, 3794 unsigned DReg, unsigned Lane, 3795 unsigned &ImplicitSReg) { 3796 // If the DPR is defined or used already, the other SPR lane will be chained 3797 // correctly, so there is nothing to be done. 3798 if (MI->definesRegister(DReg, TRI) || MI->readsRegister(DReg, TRI)) { 3799 ImplicitSReg = 0; 3800 return true; 3801 } 3802 3803 // Otherwise we need to go searching to see if the SPR is set explicitly. 3804 ImplicitSReg = TRI->getSubReg(DReg, 3805 (Lane & 1) ? ARM::ssub_0 : ARM::ssub_1); 3806 MachineBasicBlock::LivenessQueryResult LQR = 3807 MI->getParent()->computeRegisterLiveness(TRI, ImplicitSReg, MI); 3808 3809 if (LQR == MachineBasicBlock::LQR_Live) 3810 return true; 3811 else if (LQR == MachineBasicBlock::LQR_Unknown) 3812 return false; 3813 3814 // If the register is known not to be live, there is no need to add an 3815 // implicit-use. 3816 ImplicitSReg = 0; 3817 return true; 3818 } 3819 3820 void 3821 ARMBaseInstrInfo::setExecutionDomain(MachineInstr *MI, unsigned Domain) const { 3822 unsigned DstReg, SrcReg, DReg; 3823 unsigned Lane; 3824 MachineInstrBuilder MIB(*MI->getParent()->getParent(), MI); 3825 const TargetRegisterInfo *TRI = &getRegisterInfo(); 3826 switch (MI->getOpcode()) { 3827 default: 3828 llvm_unreachable("cannot handle opcode!"); 3829 break; 3830 case ARM::VMOVD: 3831 if (Domain != ExeNEON) 3832 break; 3833 3834 // Zap the predicate operands. 3835 assert(!isPredicated(MI) && "Cannot predicate a VORRd"); 3836 3837 // Source instruction is %DDst = VMOVD %DSrc, 14, %noreg (; implicits) 3838 DstReg = MI->getOperand(0).getReg(); 3839 SrcReg = MI->getOperand(1).getReg(); 3840 3841 for (unsigned i = MI->getDesc().getNumOperands(); i; --i) 3842 MI->RemoveOperand(i-1); 3843 3844 // Change to a %DDst = VORRd %DSrc, %DSrc, 14, %noreg (; implicits) 3845 MI->setDesc(get(ARM::VORRd)); 3846 AddDefaultPred(MIB.addReg(DstReg, RegState::Define) 3847 .addReg(SrcReg) 3848 .addReg(SrcReg)); 3849 break; 3850 case ARM::VMOVRS: 3851 if (Domain != ExeNEON) 3852 break; 3853 assert(!isPredicated(MI) && "Cannot predicate a VGETLN"); 3854 3855 // Source instruction is %RDst = VMOVRS %SSrc, 14, %noreg (; implicits) 3856 DstReg = MI->getOperand(0).getReg(); 3857 SrcReg = MI->getOperand(1).getReg(); 3858 3859 for (unsigned i = MI->getDesc().getNumOperands(); i; --i) 3860 MI->RemoveOperand(i-1); 3861 3862 DReg = getCorrespondingDRegAndLane(TRI, SrcReg, Lane); 3863 3864 // Convert to %RDst = VGETLNi32 %DSrc, Lane, 14, %noreg (; imps) 3865 // Note that DSrc has been widened and the other lane may be undef, which 3866 // contaminates the entire register. 3867 MI->setDesc(get(ARM::VGETLNi32)); 3868 AddDefaultPred(MIB.addReg(DstReg, RegState::Define) 3869 .addReg(DReg, RegState::Undef) 3870 .addImm(Lane)); 3871 3872 // The old source should be an implicit use, otherwise we might think it 3873 // was dead before here. 3874 MIB.addReg(SrcReg, RegState::Implicit); 3875 break; 3876 case ARM::VMOVSR: { 3877 if (Domain != ExeNEON) 3878 break; 3879 assert(!isPredicated(MI) && "Cannot predicate a VSETLN"); 3880 3881 // Source instruction is %SDst = VMOVSR %RSrc, 14, %noreg (; implicits) 3882 DstReg = MI->getOperand(0).getReg(); 3883 SrcReg = MI->getOperand(1).getReg(); 3884 3885 DReg = getCorrespondingDRegAndLane(TRI, DstReg, Lane); 3886 3887 unsigned ImplicitSReg; 3888 if (!getImplicitSPRUseForDPRUse(TRI, MI, DReg, Lane, ImplicitSReg)) 3889 break; 3890 3891 for (unsigned i = MI->getDesc().getNumOperands(); i; --i) 3892 MI->RemoveOperand(i-1); 3893 3894 // Convert to %DDst = VSETLNi32 %DDst, %RSrc, Lane, 14, %noreg (; imps) 3895 // Again DDst may be undefined at the beginning of this instruction. 3896 MI->setDesc(get(ARM::VSETLNi32)); 3897 MIB.addReg(DReg, RegState::Define) 3898 .addReg(DReg, getUndefRegState(!MI->readsRegister(DReg, TRI))) 3899 .addReg(SrcReg) 3900 .addImm(Lane); 3901 AddDefaultPred(MIB); 3902 3903 // The narrower destination must be marked as set to keep previous chains 3904 // in place. 3905 MIB.addReg(DstReg, RegState::Define | RegState::Implicit); 3906 if (ImplicitSReg != 0) 3907 MIB.addReg(ImplicitSReg, RegState::Implicit); 3908 break; 3909 } 3910 case ARM::VMOVS: { 3911 if (Domain != ExeNEON) 3912 break; 3913 3914 // Source instruction is %SDst = VMOVS %SSrc, 14, %noreg (; implicits) 3915 DstReg = MI->getOperand(0).getReg(); 3916 SrcReg = MI->getOperand(1).getReg(); 3917 3918 unsigned DstLane = 0, SrcLane = 0, DDst, DSrc; 3919 DDst = getCorrespondingDRegAndLane(TRI, DstReg, DstLane); 3920 DSrc = getCorrespondingDRegAndLane(TRI, SrcReg, SrcLane); 3921 3922 unsigned ImplicitSReg; 3923 if (!getImplicitSPRUseForDPRUse(TRI, MI, DSrc, SrcLane, ImplicitSReg)) 3924 break; 3925 3926 for (unsigned i = MI->getDesc().getNumOperands(); i; --i) 3927 MI->RemoveOperand(i-1); 3928 3929 if (DSrc == DDst) { 3930 // Destination can be: 3931 // %DDst = VDUPLN32d %DDst, Lane, 14, %noreg (; implicits) 3932 MI->setDesc(get(ARM::VDUPLN32d)); 3933 MIB.addReg(DDst, RegState::Define) 3934 .addReg(DDst, getUndefRegState(!MI->readsRegister(DDst, TRI))) 3935 .addImm(SrcLane); 3936 AddDefaultPred(MIB); 3937 3938 // Neither the source or the destination are naturally represented any 3939 // more, so add them in manually. 3940 MIB.addReg(DstReg, RegState::Implicit | RegState::Define); 3941 MIB.addReg(SrcReg, RegState::Implicit); 3942 if (ImplicitSReg != 0) 3943 MIB.addReg(ImplicitSReg, RegState::Implicit); 3944 break; 3945 } 3946 3947 // In general there's no single instruction that can perform an S <-> S 3948 // move in NEON space, but a pair of VEXT instructions *can* do the 3949 // job. It turns out that the VEXTs needed will only use DSrc once, with 3950 // the position based purely on the combination of lane-0 and lane-1 3951 // involved. For example 3952 // vmov s0, s2 -> vext.32 d0, d0, d1, #1 vext.32 d0, d0, d0, #1 3953 // vmov s1, s3 -> vext.32 d0, d1, d0, #1 vext.32 d0, d0, d0, #1 3954 // vmov s0, s3 -> vext.32 d0, d0, d0, #1 vext.32 d0, d1, d0, #1 3955 // vmov s1, s2 -> vext.32 d0, d0, d0, #1 vext.32 d0, d0, d1, #1 3956 // 3957 // Pattern of the MachineInstrs is: 3958 // %DDst = VEXTd32 %DSrc1, %DSrc2, Lane, 14, %noreg (;implicits) 3959 MachineInstrBuilder NewMIB; 3960 NewMIB = BuildMI(*MI->getParent(), MI, MI->getDebugLoc(), 3961 get(ARM::VEXTd32), DDst); 3962 3963 // On the first instruction, both DSrc and DDst may be <undef> if present. 3964 // Specifically when the original instruction didn't have them as an 3965 // <imp-use>. 3966 unsigned CurReg = SrcLane == 1 && DstLane == 1 ? DSrc : DDst; 3967 bool CurUndef = !MI->readsRegister(CurReg, TRI); 3968 NewMIB.addReg(CurReg, getUndefRegState(CurUndef)); 3969 3970 CurReg = SrcLane == 0 && DstLane == 0 ? DSrc : DDst; 3971 CurUndef = !MI->readsRegister(CurReg, TRI); 3972 NewMIB.addReg(CurReg, getUndefRegState(CurUndef)); 3973 3974 NewMIB.addImm(1); 3975 AddDefaultPred(NewMIB); 3976 3977 if (SrcLane == DstLane) 3978 NewMIB.addReg(SrcReg, RegState::Implicit); 3979 3980 MI->setDesc(get(ARM::VEXTd32)); 3981 MIB.addReg(DDst, RegState::Define); 3982 3983 // On the second instruction, DDst has definitely been defined above, so 3984 // it is not <undef>. DSrc, if present, can be <undef> as above. 3985 CurReg = SrcLane == 1 && DstLane == 0 ? DSrc : DDst; 3986 CurUndef = CurReg == DSrc && !MI->readsRegister(CurReg, TRI); 3987 MIB.addReg(CurReg, getUndefRegState(CurUndef)); 3988 3989 CurReg = SrcLane == 0 && DstLane == 1 ? DSrc : DDst; 3990 CurUndef = CurReg == DSrc && !MI->readsRegister(CurReg, TRI); 3991 MIB.addReg(CurReg, getUndefRegState(CurUndef)); 3992 3993 MIB.addImm(1); 3994 AddDefaultPred(MIB); 3995 3996 if (SrcLane != DstLane) 3997 MIB.addReg(SrcReg, RegState::Implicit); 3998 3999 // As before, the original destination is no longer represented, add it 4000 // implicitly. 4001 MIB.addReg(DstReg, RegState::Define | RegState::Implicit); 4002 if (ImplicitSReg != 0) 4003 MIB.addReg(ImplicitSReg, RegState::Implicit); 4004 break; 4005 } 4006 } 4007 4008 } 4009 4010 //===----------------------------------------------------------------------===// 4011 // Partial register updates 4012 //===----------------------------------------------------------------------===// 4013 // 4014 // Swift renames NEON registers with 64-bit granularity. That means any 4015 // instruction writing an S-reg implicitly reads the containing D-reg. The 4016 // problem is mostly avoided by translating f32 operations to v2f32 operations 4017 // on D-registers, but f32 loads are still a problem. 4018 // 4019 // These instructions can load an f32 into a NEON register: 4020 // 4021 // VLDRS - Only writes S, partial D update. 4022 // VLD1LNd32 - Writes all D-regs, explicit partial D update, 2 uops. 4023 // VLD1DUPd32 - Writes all D-regs, no partial reg update, 2 uops. 4024 // 4025 // FCONSTD can be used as a dependency-breaking instruction. 4026 4027 4028 unsigned ARMBaseInstrInfo:: 4029 getPartialRegUpdateClearance(const MachineInstr *MI, 4030 unsigned OpNum, 4031 const TargetRegisterInfo *TRI) const { 4032 // Only Swift has partial register update problems. 4033 if (!SwiftPartialUpdateClearance || !Subtarget.isSwift()) 4034 return 0; 4035 4036 assert(TRI && "Need TRI instance"); 4037 4038 const MachineOperand &MO = MI->getOperand(OpNum); 4039 if (MO.readsReg()) 4040 return 0; 4041 unsigned Reg = MO.getReg(); 4042 int UseOp = -1; 4043 4044 switch(MI->getOpcode()) { 4045 // Normal instructions writing only an S-register. 4046 case ARM::VLDRS: 4047 case ARM::FCONSTS: 4048 case ARM::VMOVSR: 4049 case ARM::VMOVv8i8: 4050 case ARM::VMOVv4i16: 4051 case ARM::VMOVv2i32: 4052 case ARM::VMOVv2f32: 4053 case ARM::VMOVv1i64: 4054 UseOp = MI->findRegisterUseOperandIdx(Reg, false, TRI); 4055 break; 4056 4057 // Explicitly reads the dependency. 4058 case ARM::VLD1LNd32: 4059 UseOp = 1; 4060 break; 4061 default: 4062 return 0; 4063 } 4064 4065 // If this instruction actually reads a value from Reg, there is no unwanted 4066 // dependency. 4067 if (UseOp != -1 && MI->getOperand(UseOp).readsReg()) 4068 return 0; 4069 4070 // We must be able to clobber the whole D-reg. 4071 if (TargetRegisterInfo::isVirtualRegister(Reg)) { 4072 // Virtual register must be a foo:ssub_0<def,undef> operand. 4073 if (!MO.getSubReg() || MI->readsVirtualRegister(Reg)) 4074 return 0; 4075 } else if (ARM::SPRRegClass.contains(Reg)) { 4076 // Physical register: MI must define the full D-reg. 4077 unsigned DReg = TRI->getMatchingSuperReg(Reg, ARM::ssub_0, 4078 &ARM::DPRRegClass); 4079 if (!DReg || !MI->definesRegister(DReg, TRI)) 4080 return 0; 4081 } 4082 4083 // MI has an unwanted D-register dependency. 4084 // Avoid defs in the previous N instructrions. 4085 return SwiftPartialUpdateClearance; 4086 } 4087 4088 // Break a partial register dependency after getPartialRegUpdateClearance 4089 // returned non-zero. 4090 void ARMBaseInstrInfo:: 4091 breakPartialRegDependency(MachineBasicBlock::iterator MI, 4092 unsigned OpNum, 4093 const TargetRegisterInfo *TRI) const { 4094 assert(MI && OpNum < MI->getDesc().getNumDefs() && "OpNum is not a def"); 4095 assert(TRI && "Need TRI instance"); 4096 4097 const MachineOperand &MO = MI->getOperand(OpNum); 4098 unsigned Reg = MO.getReg(); 4099 assert(TargetRegisterInfo::isPhysicalRegister(Reg) && 4100 "Can't break virtual register dependencies."); 4101 unsigned DReg = Reg; 4102 4103 // If MI defines an S-reg, find the corresponding D super-register. 4104 if (ARM::SPRRegClass.contains(Reg)) { 4105 DReg = ARM::D0 + (Reg - ARM::S0) / 2; 4106 assert(TRI->isSuperRegister(Reg, DReg) && "Register enums broken"); 4107 } 4108 4109 assert(ARM::DPRRegClass.contains(DReg) && "Can only break D-reg deps"); 4110 assert(MI->definesRegister(DReg, TRI) && "MI doesn't clobber full D-reg"); 4111 4112 // FIXME: In some cases, VLDRS can be changed to a VLD1DUPd32 which defines 4113 // the full D-register by loading the same value to both lanes. The 4114 // instruction is micro-coded with 2 uops, so don't do this until we can 4115 // properly schedule micro-coded instuctions. The dispatcher stalls cause 4116 // too big regressions. 4117 4118 // Insert the dependency-breaking FCONSTD before MI. 4119 // 96 is the encoding of 0.5, but the actual value doesn't matter here. 4120 AddDefaultPred(BuildMI(*MI->getParent(), MI, MI->getDebugLoc(), 4121 get(ARM::FCONSTD), DReg).addImm(96)); 4122 MI->addRegisterKilled(DReg, TRI, true); 4123 } 4124 4125 bool ARMBaseInstrInfo::hasNOP() const { 4126 return (Subtarget.getFeatureBits() & ARM::HasV6T2Ops) != 0; 4127 } 4128