1 //===-- SystemZTargetTransformInfo.cpp - SystemZ-specific TTI -------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // 9 // This file implements a TargetTransformInfo analysis pass specific to the 10 // SystemZ target machine. It uses the target's detailed information to provide 11 // more precise answers to certain TTI queries, while letting the target 12 // independent and default TTI implementations handle the rest. 13 // 14 //===----------------------------------------------------------------------===// 15 16 #include "SystemZTargetTransformInfo.h" 17 #include "llvm/Analysis/TargetTransformInfo.h" 18 #include "llvm/CodeGen/BasicTTIImpl.h" 19 #include "llvm/CodeGen/CostTable.h" 20 #include "llvm/CodeGen/TargetLowering.h" 21 #include "llvm/IR/IntrinsicInst.h" 22 #include "llvm/Support/Debug.h" 23 using namespace llvm; 24 25 #define DEBUG_TYPE "systemztti" 26 27 //===----------------------------------------------------------------------===// 28 // 29 // SystemZ cost model. 30 // 31 //===----------------------------------------------------------------------===// 32 33 int SystemZTTIImpl::getIntImmCost(const APInt &Imm, Type *Ty, 34 TTI::TargetCostKind CostKind) { 35 assert(Ty->isIntegerTy()); 36 37 unsigned BitSize = Ty->getPrimitiveSizeInBits(); 38 // There is no cost model for constants with a bit size of 0. Return TCC_Free 39 // here, so that constant hoisting will ignore this constant. 40 if (BitSize == 0) 41 return TTI::TCC_Free; 42 // No cost model for operations on integers larger than 64 bit implemented yet. 43 if (BitSize > 64) 44 return TTI::TCC_Free; 45 46 if (Imm == 0) 47 return TTI::TCC_Free; 48 49 if (Imm.getBitWidth() <= 64) { 50 // Constants loaded via lgfi. 51 if (isInt<32>(Imm.getSExtValue())) 52 return TTI::TCC_Basic; 53 // Constants loaded via llilf. 54 if (isUInt<32>(Imm.getZExtValue())) 55 return TTI::TCC_Basic; 56 // Constants loaded via llihf: 57 if ((Imm.getZExtValue() & 0xffffffff) == 0) 58 return TTI::TCC_Basic; 59 60 return 2 * TTI::TCC_Basic; 61 } 62 63 return 4 * TTI::TCC_Basic; 64 } 65 66 int SystemZTTIImpl::getIntImmCostInst(unsigned Opcode, unsigned Idx, 67 const APInt &Imm, Type *Ty, 68 TTI::TargetCostKind CostKind, 69 Instruction *Inst) { 70 assert(Ty->isIntegerTy()); 71 72 unsigned BitSize = Ty->getPrimitiveSizeInBits(); 73 // There is no cost model for constants with a bit size of 0. Return TCC_Free 74 // here, so that constant hoisting will ignore this constant. 75 if (BitSize == 0) 76 return TTI::TCC_Free; 77 // No cost model for operations on integers larger than 64 bit implemented yet. 78 if (BitSize > 64) 79 return TTI::TCC_Free; 80 81 switch (Opcode) { 82 default: 83 return TTI::TCC_Free; 84 case Instruction::GetElementPtr: 85 // Always hoist the base address of a GetElementPtr. This prevents the 86 // creation of new constants for every base constant that gets constant 87 // folded with the offset. 88 if (Idx == 0) 89 return 2 * TTI::TCC_Basic; 90 return TTI::TCC_Free; 91 case Instruction::Store: 92 if (Idx == 0 && Imm.getBitWidth() <= 64) { 93 // Any 8-bit immediate store can by implemented via mvi. 94 if (BitSize == 8) 95 return TTI::TCC_Free; 96 // 16-bit immediate values can be stored via mvhhi/mvhi/mvghi. 97 if (isInt<16>(Imm.getSExtValue())) 98 return TTI::TCC_Free; 99 } 100 break; 101 case Instruction::ICmp: 102 if (Idx == 1 && Imm.getBitWidth() <= 64) { 103 // Comparisons against signed 32-bit immediates implemented via cgfi. 104 if (isInt<32>(Imm.getSExtValue())) 105 return TTI::TCC_Free; 106 // Comparisons against unsigned 32-bit immediates implemented via clgfi. 107 if (isUInt<32>(Imm.getZExtValue())) 108 return TTI::TCC_Free; 109 } 110 break; 111 case Instruction::Add: 112 case Instruction::Sub: 113 if (Idx == 1 && Imm.getBitWidth() <= 64) { 114 // We use algfi/slgfi to add/subtract 32-bit unsigned immediates. 115 if (isUInt<32>(Imm.getZExtValue())) 116 return TTI::TCC_Free; 117 // Or their negation, by swapping addition vs. subtraction. 118 if (isUInt<32>(-Imm.getSExtValue())) 119 return TTI::TCC_Free; 120 } 121 break; 122 case Instruction::Mul: 123 if (Idx == 1 && Imm.getBitWidth() <= 64) { 124 // We use msgfi to multiply by 32-bit signed immediates. 125 if (isInt<32>(Imm.getSExtValue())) 126 return TTI::TCC_Free; 127 } 128 break; 129 case Instruction::Or: 130 case Instruction::Xor: 131 if (Idx == 1 && Imm.getBitWidth() <= 64) { 132 // Masks supported by oilf/xilf. 133 if (isUInt<32>(Imm.getZExtValue())) 134 return TTI::TCC_Free; 135 // Masks supported by oihf/xihf. 136 if ((Imm.getZExtValue() & 0xffffffff) == 0) 137 return TTI::TCC_Free; 138 } 139 break; 140 case Instruction::And: 141 if (Idx == 1 && Imm.getBitWidth() <= 64) { 142 // Any 32-bit AND operation can by implemented via nilf. 143 if (BitSize <= 32) 144 return TTI::TCC_Free; 145 // 64-bit masks supported by nilf. 146 if (isUInt<32>(~Imm.getZExtValue())) 147 return TTI::TCC_Free; 148 // 64-bit masks supported by nilh. 149 if ((Imm.getZExtValue() & 0xffffffff) == 0xffffffff) 150 return TTI::TCC_Free; 151 // Some 64-bit AND operations can be implemented via risbg. 152 const SystemZInstrInfo *TII = ST->getInstrInfo(); 153 unsigned Start, End; 154 if (TII->isRxSBGMask(Imm.getZExtValue(), BitSize, Start, End)) 155 return TTI::TCC_Free; 156 } 157 break; 158 case Instruction::Shl: 159 case Instruction::LShr: 160 case Instruction::AShr: 161 // Always return TCC_Free for the shift value of a shift instruction. 162 if (Idx == 1) 163 return TTI::TCC_Free; 164 break; 165 case Instruction::UDiv: 166 case Instruction::SDiv: 167 case Instruction::URem: 168 case Instruction::SRem: 169 case Instruction::Trunc: 170 case Instruction::ZExt: 171 case Instruction::SExt: 172 case Instruction::IntToPtr: 173 case Instruction::PtrToInt: 174 case Instruction::BitCast: 175 case Instruction::PHI: 176 case Instruction::Call: 177 case Instruction::Select: 178 case Instruction::Ret: 179 case Instruction::Load: 180 break; 181 } 182 183 return SystemZTTIImpl::getIntImmCost(Imm, Ty, CostKind); 184 } 185 186 int SystemZTTIImpl::getIntImmCostIntrin(Intrinsic::ID IID, unsigned Idx, 187 const APInt &Imm, Type *Ty, 188 TTI::TargetCostKind CostKind) { 189 assert(Ty->isIntegerTy()); 190 191 unsigned BitSize = Ty->getPrimitiveSizeInBits(); 192 // There is no cost model for constants with a bit size of 0. Return TCC_Free 193 // here, so that constant hoisting will ignore this constant. 194 if (BitSize == 0) 195 return TTI::TCC_Free; 196 // No cost model for operations on integers larger than 64 bit implemented yet. 197 if (BitSize > 64) 198 return TTI::TCC_Free; 199 200 switch (IID) { 201 default: 202 return TTI::TCC_Free; 203 case Intrinsic::sadd_with_overflow: 204 case Intrinsic::uadd_with_overflow: 205 case Intrinsic::ssub_with_overflow: 206 case Intrinsic::usub_with_overflow: 207 // These get expanded to include a normal addition/subtraction. 208 if (Idx == 1 && Imm.getBitWidth() <= 64) { 209 if (isUInt<32>(Imm.getZExtValue())) 210 return TTI::TCC_Free; 211 if (isUInt<32>(-Imm.getSExtValue())) 212 return TTI::TCC_Free; 213 } 214 break; 215 case Intrinsic::smul_with_overflow: 216 case Intrinsic::umul_with_overflow: 217 // These get expanded to include a normal multiplication. 218 if (Idx == 1 && Imm.getBitWidth() <= 64) { 219 if (isInt<32>(Imm.getSExtValue())) 220 return TTI::TCC_Free; 221 } 222 break; 223 case Intrinsic::experimental_stackmap: 224 if ((Idx < 2) || (Imm.getBitWidth() <= 64 && isInt<64>(Imm.getSExtValue()))) 225 return TTI::TCC_Free; 226 break; 227 case Intrinsic::experimental_patchpoint_void: 228 case Intrinsic::experimental_patchpoint_i64: 229 if ((Idx < 4) || (Imm.getBitWidth() <= 64 && isInt<64>(Imm.getSExtValue()))) 230 return TTI::TCC_Free; 231 break; 232 } 233 return SystemZTTIImpl::getIntImmCost(Imm, Ty, CostKind); 234 } 235 236 TargetTransformInfo::PopcntSupportKind 237 SystemZTTIImpl::getPopcntSupport(unsigned TyWidth) { 238 assert(isPowerOf2_32(TyWidth) && "Type width must be power of 2"); 239 if (ST->hasPopulationCount() && TyWidth <= 64) 240 return TTI::PSK_FastHardware; 241 return TTI::PSK_Software; 242 } 243 244 void SystemZTTIImpl::getUnrollingPreferences(Loop *L, ScalarEvolution &SE, 245 TTI::UnrollingPreferences &UP) { 246 // Find out if L contains a call, what the machine instruction count 247 // estimate is, and how many stores there are. 248 bool HasCall = false; 249 unsigned NumStores = 0; 250 for (auto &BB : L->blocks()) 251 for (auto &I : *BB) { 252 if (isa<CallInst>(&I) || isa<InvokeInst>(&I)) { 253 if (const Function *F = cast<CallBase>(I).getCalledFunction()) { 254 if (isLoweredToCall(F)) 255 HasCall = true; 256 if (F->getIntrinsicID() == Intrinsic::memcpy || 257 F->getIntrinsicID() == Intrinsic::memset) 258 NumStores++; 259 } else { // indirect call. 260 HasCall = true; 261 } 262 } 263 if (isa<StoreInst>(&I)) { 264 Type *MemAccessTy = I.getOperand(0)->getType(); 265 NumStores += getMemoryOpCost(Instruction::Store, MemAccessTy, None, 0, 266 TTI::TCK_RecipThroughput); 267 } 268 } 269 270 // The z13 processor will run out of store tags if too many stores 271 // are fed into it too quickly. Therefore make sure there are not 272 // too many stores in the resulting unrolled loop. 273 unsigned const Max = (NumStores ? (12 / NumStores) : UINT_MAX); 274 275 if (HasCall) { 276 // Only allow full unrolling if loop has any calls. 277 UP.FullUnrollMaxCount = Max; 278 UP.MaxCount = 1; 279 return; 280 } 281 282 UP.MaxCount = Max; 283 if (UP.MaxCount <= 1) 284 return; 285 286 // Allow partial and runtime trip count unrolling. 287 UP.Partial = UP.Runtime = true; 288 289 UP.PartialThreshold = 75; 290 UP.DefaultUnrollRuntimeCount = 4; 291 292 // Allow expensive instructions in the pre-header of the loop. 293 UP.AllowExpensiveTripCount = true; 294 295 UP.Force = true; 296 } 297 298 void SystemZTTIImpl::getPeelingPreferences(Loop *L, ScalarEvolution &SE, 299 TTI::PeelingPreferences &PP) { 300 BaseT::getPeelingPreferences(L, SE, PP); 301 } 302 303 bool SystemZTTIImpl::isLSRCostLess(TargetTransformInfo::LSRCost &C1, 304 TargetTransformInfo::LSRCost &C2) { 305 // SystemZ specific: check instruction count (first), and don't care about 306 // ImmCost, since offsets are checked explicitly. 307 return std::tie(C1.Insns, C1.NumRegs, C1.AddRecCost, 308 C1.NumIVMuls, C1.NumBaseAdds, 309 C1.ScaleCost, C1.SetupCost) < 310 std::tie(C2.Insns, C2.NumRegs, C2.AddRecCost, 311 C2.NumIVMuls, C2.NumBaseAdds, 312 C2.ScaleCost, C2.SetupCost); 313 } 314 315 unsigned SystemZTTIImpl::getNumberOfRegisters(unsigned ClassID) const { 316 bool Vector = (ClassID == 1); 317 if (!Vector) 318 // Discount the stack pointer. Also leave out %r0, since it can't 319 // be used in an address. 320 return 14; 321 if (ST->hasVector()) 322 return 32; 323 return 0; 324 } 325 326 TypeSize 327 SystemZTTIImpl::getRegisterBitWidth(TargetTransformInfo::RegisterKind K) const { 328 switch (K) { 329 case TargetTransformInfo::RGK_Scalar: 330 return TypeSize::getFixed(64); 331 case TargetTransformInfo::RGK_FixedWidthVector: 332 return TypeSize::getFixed(ST->hasVector() ? 128 : 0); 333 case TargetTransformInfo::RGK_ScalableVector: 334 return TypeSize::getScalable(0); 335 } 336 337 llvm_unreachable("Unsupported register kind"); 338 } 339 340 unsigned SystemZTTIImpl::getMinPrefetchStride(unsigned NumMemAccesses, 341 unsigned NumStridedMemAccesses, 342 unsigned NumPrefetches, 343 bool HasCall) const { 344 // Don't prefetch a loop with many far apart accesses. 345 if (NumPrefetches > 16) 346 return UINT_MAX; 347 348 // Emit prefetch instructions for smaller strides in cases where we think 349 // the hardware prefetcher might not be able to keep up. 350 if (NumStridedMemAccesses > 32 && !HasCall && 351 (NumMemAccesses - NumStridedMemAccesses) * 32 <= NumStridedMemAccesses) 352 return 1; 353 354 return ST->hasMiscellaneousExtensions3() ? 8192 : 2048; 355 } 356 357 bool SystemZTTIImpl::hasDivRemOp(Type *DataType, bool IsSigned) { 358 EVT VT = TLI->getValueType(DL, DataType); 359 return (VT.isScalarInteger() && TLI->isTypeLegal(VT)); 360 } 361 362 // Return the bit size for the scalar type or vector element 363 // type. getScalarSizeInBits() returns 0 for a pointer type. 364 static unsigned getScalarSizeInBits(Type *Ty) { 365 unsigned Size = 366 (Ty->isPtrOrPtrVectorTy() ? 64U : Ty->getScalarSizeInBits()); 367 assert(Size > 0 && "Element must have non-zero size."); 368 return Size; 369 } 370 371 // getNumberOfParts() calls getTypeLegalizationCost() which splits the vector 372 // type until it is legal. This would e.g. return 4 for <6 x i64>, instead of 373 // 3. 374 static unsigned getNumVectorRegs(Type *Ty) { 375 auto *VTy = cast<FixedVectorType>(Ty); 376 unsigned WideBits = getScalarSizeInBits(Ty) * VTy->getNumElements(); 377 assert(WideBits > 0 && "Could not compute size of vector"); 378 return ((WideBits % 128U) ? ((WideBits / 128U) + 1) : (WideBits / 128U)); 379 } 380 381 int SystemZTTIImpl::getArithmeticInstrCost( 382 unsigned Opcode, Type *Ty, TTI::TargetCostKind CostKind, 383 TTI::OperandValueKind Op1Info, 384 TTI::OperandValueKind Op2Info, TTI::OperandValueProperties Opd1PropInfo, 385 TTI::OperandValueProperties Opd2PropInfo, ArrayRef<const Value *> Args, 386 const Instruction *CxtI) { 387 388 // TODO: Handle more cost kinds. 389 if (CostKind != TTI::TCK_RecipThroughput) 390 return BaseT::getArithmeticInstrCost(Opcode, Ty, CostKind, Op1Info, 391 Op2Info, Opd1PropInfo, 392 Opd2PropInfo, Args, CxtI); 393 394 // TODO: return a good value for BB-VECTORIZER that includes the 395 // immediate loads, which we do not want to count for the loop 396 // vectorizer, since they are hopefully hoisted out of the loop. This 397 // would require a new parameter 'InLoop', but not sure if constant 398 // args are common enough to motivate this. 399 400 unsigned ScalarBits = Ty->getScalarSizeInBits(); 401 402 // There are thre cases of division and remainder: Dividing with a register 403 // needs a divide instruction. A divisor which is a power of two constant 404 // can be implemented with a sequence of shifts. Any other constant needs a 405 // multiply and shifts. 406 const unsigned DivInstrCost = 20; 407 const unsigned DivMulSeqCost = 10; 408 const unsigned SDivPow2Cost = 4; 409 410 bool SignedDivRem = 411 Opcode == Instruction::SDiv || Opcode == Instruction::SRem; 412 bool UnsignedDivRem = 413 Opcode == Instruction::UDiv || Opcode == Instruction::URem; 414 415 // Check for a constant divisor. 416 bool DivRemConst = false; 417 bool DivRemConstPow2 = false; 418 if ((SignedDivRem || UnsignedDivRem) && Args.size() == 2) { 419 if (const Constant *C = dyn_cast<Constant>(Args[1])) { 420 const ConstantInt *CVal = 421 (C->getType()->isVectorTy() 422 ? dyn_cast_or_null<const ConstantInt>(C->getSplatValue()) 423 : dyn_cast<const ConstantInt>(C)); 424 if (CVal != nullptr && 425 (CVal->getValue().isPowerOf2() || (-CVal->getValue()).isPowerOf2())) 426 DivRemConstPow2 = true; 427 else 428 DivRemConst = true; 429 } 430 } 431 432 if (!Ty->isVectorTy()) { 433 // These FP operations are supported with a dedicated instruction for 434 // float, double and fp128 (base implementation assumes float generally 435 // costs 2). 436 if (Opcode == Instruction::FAdd || Opcode == Instruction::FSub || 437 Opcode == Instruction::FMul || Opcode == Instruction::FDiv) 438 return 1; 439 440 // There is no native support for FRem. 441 if (Opcode == Instruction::FRem) 442 return LIBCALL_COST; 443 444 // Give discount for some combined logical operations if supported. 445 if (Args.size() == 2 && ST->hasMiscellaneousExtensions3()) { 446 if (Opcode == Instruction::Xor) { 447 for (const Value *A : Args) { 448 if (const Instruction *I = dyn_cast<Instruction>(A)) 449 if (I->hasOneUse() && 450 (I->getOpcode() == Instruction::And || 451 I->getOpcode() == Instruction::Or || 452 I->getOpcode() == Instruction::Xor)) 453 return 0; 454 } 455 } 456 else if (Opcode == Instruction::Or || Opcode == Instruction::And) { 457 for (const Value *A : Args) { 458 if (const Instruction *I = dyn_cast<Instruction>(A)) 459 if (I->hasOneUse() && I->getOpcode() == Instruction::Xor) 460 return 0; 461 } 462 } 463 } 464 465 // Or requires one instruction, although it has custom handling for i64. 466 if (Opcode == Instruction::Or) 467 return 1; 468 469 if (Opcode == Instruction::Xor && ScalarBits == 1) { 470 if (ST->hasLoadStoreOnCond2()) 471 return 5; // 2 * (li 0; loc 1); xor 472 return 7; // 2 * ipm sequences ; xor ; shift ; compare 473 } 474 475 if (DivRemConstPow2) 476 return (SignedDivRem ? SDivPow2Cost : 1); 477 if (DivRemConst) 478 return DivMulSeqCost; 479 if (SignedDivRem || UnsignedDivRem) 480 return DivInstrCost; 481 } 482 else if (ST->hasVector()) { 483 auto *VTy = cast<FixedVectorType>(Ty); 484 unsigned VF = VTy->getNumElements(); 485 unsigned NumVectors = getNumVectorRegs(Ty); 486 487 // These vector operations are custom handled, but are still supported 488 // with one instruction per vector, regardless of element size. 489 if (Opcode == Instruction::Shl || Opcode == Instruction::LShr || 490 Opcode == Instruction::AShr) { 491 return NumVectors; 492 } 493 494 if (DivRemConstPow2) 495 return (NumVectors * (SignedDivRem ? SDivPow2Cost : 1)); 496 if (DivRemConst) { 497 SmallVector<Type *> Tys(Args.size(), Ty); 498 return VF * DivMulSeqCost + getScalarizationOverhead(VTy, Args, Tys); 499 } 500 if ((SignedDivRem || UnsignedDivRem) && VF > 4) 501 // Temporary hack: disable high vectorization factors with integer 502 // division/remainder, which will get scalarized and handled with 503 // GR128 registers. The mischeduler is not clever enough to avoid 504 // spilling yet. 505 return 1000; 506 507 // These FP operations are supported with a single vector instruction for 508 // double (base implementation assumes float generally costs 2). For 509 // FP128, the scalar cost is 1, and there is no overhead since the values 510 // are already in scalar registers. 511 if (Opcode == Instruction::FAdd || Opcode == Instruction::FSub || 512 Opcode == Instruction::FMul || Opcode == Instruction::FDiv) { 513 switch (ScalarBits) { 514 case 32: { 515 // The vector enhancements facility 1 provides v4f32 instructions. 516 if (ST->hasVectorEnhancements1()) 517 return NumVectors; 518 // Return the cost of multiple scalar invocation plus the cost of 519 // inserting and extracting the values. 520 unsigned ScalarCost = 521 getArithmeticInstrCost(Opcode, Ty->getScalarType(), CostKind); 522 SmallVector<Type *> Tys(Args.size(), Ty); 523 unsigned Cost = 524 (VF * ScalarCost) + getScalarizationOverhead(VTy, Args, Tys); 525 // FIXME: VF 2 for these FP operations are currently just as 526 // expensive as for VF 4. 527 if (VF == 2) 528 Cost *= 2; 529 return Cost; 530 } 531 case 64: 532 case 128: 533 return NumVectors; 534 default: 535 break; 536 } 537 } 538 539 // There is no native support for FRem. 540 if (Opcode == Instruction::FRem) { 541 SmallVector<Type *> Tys(Args.size(), Ty); 542 unsigned Cost = 543 (VF * LIBCALL_COST) + getScalarizationOverhead(VTy, Args, Tys); 544 // FIXME: VF 2 for float is currently just as expensive as for VF 4. 545 if (VF == 2 && ScalarBits == 32) 546 Cost *= 2; 547 return Cost; 548 } 549 } 550 551 // Fallback to the default implementation. 552 return BaseT::getArithmeticInstrCost(Opcode, Ty, CostKind, Op1Info, Op2Info, 553 Opd1PropInfo, Opd2PropInfo, Args, CxtI); 554 } 555 556 int SystemZTTIImpl::getShuffleCost(TTI::ShuffleKind Kind, VectorType *Tp, 557 ArrayRef<int> Mask, int Index, 558 VectorType *SubTp) { 559 if (ST->hasVector()) { 560 unsigned NumVectors = getNumVectorRegs(Tp); 561 562 // TODO: Since fp32 is expanded, the shuffle cost should always be 0. 563 564 // FP128 values are always in scalar registers, so there is no work 565 // involved with a shuffle, except for broadcast. In that case register 566 // moves are done with a single instruction per element. 567 if (Tp->getScalarType()->isFP128Ty()) 568 return (Kind == TargetTransformInfo::SK_Broadcast ? NumVectors - 1 : 0); 569 570 switch (Kind) { 571 case TargetTransformInfo::SK_ExtractSubvector: 572 // ExtractSubvector Index indicates start offset. 573 574 // Extracting a subvector from first index is a noop. 575 return (Index == 0 ? 0 : NumVectors); 576 577 case TargetTransformInfo::SK_Broadcast: 578 // Loop vectorizer calls here to figure out the extra cost of 579 // broadcasting a loaded value to all elements of a vector. Since vlrep 580 // loads and replicates with a single instruction, adjust the returned 581 // value. 582 return NumVectors - 1; 583 584 default: 585 586 // SystemZ supports single instruction permutation / replication. 587 return NumVectors; 588 } 589 } 590 591 return BaseT::getShuffleCost(Kind, Tp, Mask, Index, SubTp); 592 } 593 594 // Return the log2 difference of the element sizes of the two vector types. 595 static unsigned getElSizeLog2Diff(Type *Ty0, Type *Ty1) { 596 unsigned Bits0 = Ty0->getScalarSizeInBits(); 597 unsigned Bits1 = Ty1->getScalarSizeInBits(); 598 599 if (Bits1 > Bits0) 600 return (Log2_32(Bits1) - Log2_32(Bits0)); 601 602 return (Log2_32(Bits0) - Log2_32(Bits1)); 603 } 604 605 // Return the number of instructions needed to truncate SrcTy to DstTy. 606 unsigned SystemZTTIImpl:: 607 getVectorTruncCost(Type *SrcTy, Type *DstTy) { 608 assert (SrcTy->isVectorTy() && DstTy->isVectorTy()); 609 assert(SrcTy->getPrimitiveSizeInBits().getFixedSize() > 610 DstTy->getPrimitiveSizeInBits().getFixedSize() && 611 "Packing must reduce size of vector type."); 612 assert(cast<FixedVectorType>(SrcTy)->getNumElements() == 613 cast<FixedVectorType>(DstTy)->getNumElements() && 614 "Packing should not change number of elements."); 615 616 // TODO: Since fp32 is expanded, the extract cost should always be 0. 617 618 unsigned NumParts = getNumVectorRegs(SrcTy); 619 if (NumParts <= 2) 620 // Up to 2 vector registers can be truncated efficiently with pack or 621 // permute. The latter requires an immediate mask to be loaded, which 622 // typically gets hoisted out of a loop. TODO: return a good value for 623 // BB-VECTORIZER that includes the immediate loads, which we do not want 624 // to count for the loop vectorizer. 625 return 1; 626 627 unsigned Cost = 0; 628 unsigned Log2Diff = getElSizeLog2Diff(SrcTy, DstTy); 629 unsigned VF = cast<FixedVectorType>(SrcTy)->getNumElements(); 630 for (unsigned P = 0; P < Log2Diff; ++P) { 631 if (NumParts > 1) 632 NumParts /= 2; 633 Cost += NumParts; 634 } 635 636 // Currently, a general mix of permutes and pack instructions is output by 637 // isel, which follow the cost computation above except for this case which 638 // is one instruction less: 639 if (VF == 8 && SrcTy->getScalarSizeInBits() == 64 && 640 DstTy->getScalarSizeInBits() == 8) 641 Cost--; 642 643 return Cost; 644 } 645 646 // Return the cost of converting a vector bitmask produced by a compare 647 // (SrcTy), to the type of the select or extend instruction (DstTy). 648 unsigned SystemZTTIImpl:: 649 getVectorBitmaskConversionCost(Type *SrcTy, Type *DstTy) { 650 assert (SrcTy->isVectorTy() && DstTy->isVectorTy() && 651 "Should only be called with vector types."); 652 653 unsigned PackCost = 0; 654 unsigned SrcScalarBits = SrcTy->getScalarSizeInBits(); 655 unsigned DstScalarBits = DstTy->getScalarSizeInBits(); 656 unsigned Log2Diff = getElSizeLog2Diff(SrcTy, DstTy); 657 if (SrcScalarBits > DstScalarBits) 658 // The bitmask will be truncated. 659 PackCost = getVectorTruncCost(SrcTy, DstTy); 660 else if (SrcScalarBits < DstScalarBits) { 661 unsigned DstNumParts = getNumVectorRegs(DstTy); 662 // Each vector select needs its part of the bitmask unpacked. 663 PackCost = Log2Diff * DstNumParts; 664 // Extra cost for moving part of mask before unpacking. 665 PackCost += DstNumParts - 1; 666 } 667 668 return PackCost; 669 } 670 671 // Return the type of the compared operands. This is needed to compute the 672 // cost for a Select / ZExt or SExt instruction. 673 static Type *getCmpOpsType(const Instruction *I, unsigned VF = 1) { 674 Type *OpTy = nullptr; 675 if (CmpInst *CI = dyn_cast<CmpInst>(I->getOperand(0))) 676 OpTy = CI->getOperand(0)->getType(); 677 else if (Instruction *LogicI = dyn_cast<Instruction>(I->getOperand(0))) 678 if (LogicI->getNumOperands() == 2) 679 if (CmpInst *CI0 = dyn_cast<CmpInst>(LogicI->getOperand(0))) 680 if (isa<CmpInst>(LogicI->getOperand(1))) 681 OpTy = CI0->getOperand(0)->getType(); 682 683 if (OpTy != nullptr) { 684 if (VF == 1) { 685 assert (!OpTy->isVectorTy() && "Expected scalar type"); 686 return OpTy; 687 } 688 // Return the potentially vectorized type based on 'I' and 'VF'. 'I' may 689 // be either scalar or already vectorized with a same or lesser VF. 690 Type *ElTy = OpTy->getScalarType(); 691 return FixedVectorType::get(ElTy, VF); 692 } 693 694 return nullptr; 695 } 696 697 // Get the cost of converting a boolean vector to a vector with same width 698 // and element size as Dst, plus the cost of zero extending if needed. 699 unsigned SystemZTTIImpl:: 700 getBoolVecToIntConversionCost(unsigned Opcode, Type *Dst, 701 const Instruction *I) { 702 auto *DstVTy = cast<FixedVectorType>(Dst); 703 unsigned VF = DstVTy->getNumElements(); 704 unsigned Cost = 0; 705 // If we know what the widths of the compared operands, get any cost of 706 // converting it to match Dst. Otherwise assume same widths. 707 Type *CmpOpTy = ((I != nullptr) ? getCmpOpsType(I, VF) : nullptr); 708 if (CmpOpTy != nullptr) 709 Cost = getVectorBitmaskConversionCost(CmpOpTy, Dst); 710 if (Opcode == Instruction::ZExt || Opcode == Instruction::UIToFP) 711 // One 'vn' per dst vector with an immediate mask. 712 Cost += getNumVectorRegs(Dst); 713 return Cost; 714 } 715 716 InstructionCost SystemZTTIImpl::getCastInstrCost(unsigned Opcode, Type *Dst, 717 Type *Src, 718 TTI::CastContextHint CCH, 719 TTI::TargetCostKind CostKind, 720 const Instruction *I) { 721 // FIXME: Can the logic below also be used for these cost kinds? 722 if (CostKind == TTI::TCK_CodeSize || CostKind == TTI::TCK_SizeAndLatency) { 723 auto BaseCost = BaseT::getCastInstrCost(Opcode, Dst, Src, CCH, CostKind, I); 724 return BaseCost == 0 ? BaseCost : 1; 725 } 726 727 unsigned DstScalarBits = Dst->getScalarSizeInBits(); 728 unsigned SrcScalarBits = Src->getScalarSizeInBits(); 729 730 if (!Src->isVectorTy()) { 731 assert (!Dst->isVectorTy()); 732 733 if (Opcode == Instruction::SIToFP || Opcode == Instruction::UIToFP) { 734 if (SrcScalarBits >= 32 || 735 (I != nullptr && isa<LoadInst>(I->getOperand(0)))) 736 return 1; 737 return SrcScalarBits > 1 ? 2 /*i8/i16 extend*/ : 5 /*branch seq.*/; 738 } 739 740 if ((Opcode == Instruction::ZExt || Opcode == Instruction::SExt) && 741 Src->isIntegerTy(1)) { 742 if (ST->hasLoadStoreOnCond2()) 743 return 2; // li 0; loc 1 744 745 // This should be extension of a compare i1 result, which is done with 746 // ipm and a varying sequence of instructions. 747 unsigned Cost = 0; 748 if (Opcode == Instruction::SExt) 749 Cost = (DstScalarBits < 64 ? 3 : 4); 750 if (Opcode == Instruction::ZExt) 751 Cost = 3; 752 Type *CmpOpTy = ((I != nullptr) ? getCmpOpsType(I) : nullptr); 753 if (CmpOpTy != nullptr && CmpOpTy->isFloatingPointTy()) 754 // If operands of an fp-type was compared, this costs +1. 755 Cost++; 756 return Cost; 757 } 758 } 759 else if (ST->hasVector()) { 760 // Vector to scalar cast. 761 auto *SrcVecTy = cast<FixedVectorType>(Src); 762 auto *DstVecTy = dyn_cast<FixedVectorType>(Dst); 763 if (!DstVecTy) { 764 // TODO: tune vector-to-scalar cast. 765 return BaseT::getCastInstrCost(Opcode, Dst, Src, CCH, CostKind, I); 766 } 767 unsigned VF = SrcVecTy->getNumElements(); 768 unsigned NumDstVectors = getNumVectorRegs(Dst); 769 unsigned NumSrcVectors = getNumVectorRegs(Src); 770 771 if (Opcode == Instruction::Trunc) { 772 if (Src->getScalarSizeInBits() == Dst->getScalarSizeInBits()) 773 return 0; // Check for NOOP conversions. 774 return getVectorTruncCost(Src, Dst); 775 } 776 777 if (Opcode == Instruction::ZExt || Opcode == Instruction::SExt) { 778 if (SrcScalarBits >= 8) { 779 // ZExt/SExt will be handled with one unpack per doubling of width. 780 unsigned NumUnpacks = getElSizeLog2Diff(Src, Dst); 781 782 // For types that spans multiple vector registers, some additional 783 // instructions are used to setup the unpacking. 784 unsigned NumSrcVectorOps = 785 (NumUnpacks > 1 ? (NumDstVectors - NumSrcVectors) 786 : (NumDstVectors / 2)); 787 788 return (NumUnpacks * NumDstVectors) + NumSrcVectorOps; 789 } 790 else if (SrcScalarBits == 1) 791 return getBoolVecToIntConversionCost(Opcode, Dst, I); 792 } 793 794 if (Opcode == Instruction::SIToFP || Opcode == Instruction::UIToFP || 795 Opcode == Instruction::FPToSI || Opcode == Instruction::FPToUI) { 796 // TODO: Fix base implementation which could simplify things a bit here 797 // (seems to miss on differentiating on scalar/vector types). 798 799 // Only 64 bit vector conversions are natively supported before z15. 800 if (DstScalarBits == 64 || ST->hasVectorEnhancements2()) { 801 if (SrcScalarBits == DstScalarBits) 802 return NumDstVectors; 803 804 if (SrcScalarBits == 1) 805 return getBoolVecToIntConversionCost(Opcode, Dst, I) + NumDstVectors; 806 } 807 808 // Return the cost of multiple scalar invocation plus the cost of 809 // inserting and extracting the values. Base implementation does not 810 // realize float->int gets scalarized. 811 InstructionCost ScalarCost = getCastInstrCost( 812 Opcode, Dst->getScalarType(), Src->getScalarType(), CCH, CostKind); 813 InstructionCost TotCost = VF * ScalarCost; 814 bool NeedsInserts = true, NeedsExtracts = true; 815 // FP128 registers do not get inserted or extracted. 816 if (DstScalarBits == 128 && 817 (Opcode == Instruction::SIToFP || Opcode == Instruction::UIToFP)) 818 NeedsInserts = false; 819 if (SrcScalarBits == 128 && 820 (Opcode == Instruction::FPToSI || Opcode == Instruction::FPToUI)) 821 NeedsExtracts = false; 822 823 TotCost += getScalarizationOverhead(SrcVecTy, false, NeedsExtracts); 824 TotCost += getScalarizationOverhead(DstVecTy, NeedsInserts, false); 825 826 // FIXME: VF 2 for float<->i32 is currently just as expensive as for VF 4. 827 if (VF == 2 && SrcScalarBits == 32 && DstScalarBits == 32) 828 TotCost *= 2; 829 830 return TotCost; 831 } 832 833 if (Opcode == Instruction::FPTrunc) { 834 if (SrcScalarBits == 128) // fp128 -> double/float + inserts of elements. 835 return VF /*ldxbr/lexbr*/ + 836 getScalarizationOverhead(DstVecTy, true, false); 837 else // double -> float 838 return VF / 2 /*vledb*/ + std::max(1U, VF / 4 /*vperm*/); 839 } 840 841 if (Opcode == Instruction::FPExt) { 842 if (SrcScalarBits == 32 && DstScalarBits == 64) { 843 // float -> double is very rare and currently unoptimized. Instead of 844 // using vldeb, which can do two at a time, all conversions are 845 // scalarized. 846 return VF * 2; 847 } 848 // -> fp128. VF * lxdb/lxeb + extraction of elements. 849 return VF + getScalarizationOverhead(SrcVecTy, false, true); 850 } 851 } 852 853 return BaseT::getCastInstrCost(Opcode, Dst, Src, CCH, CostKind, I); 854 } 855 856 // Scalar i8 / i16 operations will typically be made after first extending 857 // the operands to i32. 858 static unsigned getOperandsExtensionCost(const Instruction *I) { 859 unsigned ExtCost = 0; 860 for (Value *Op : I->operands()) 861 // A load of i8 or i16 sign/zero extends to i32. 862 if (!isa<LoadInst>(Op) && !isa<ConstantInt>(Op)) 863 ExtCost++; 864 865 return ExtCost; 866 } 867 868 InstructionCost SystemZTTIImpl::getCmpSelInstrCost(unsigned Opcode, Type *ValTy, 869 Type *CondTy, 870 CmpInst::Predicate VecPred, 871 TTI::TargetCostKind CostKind, 872 const Instruction *I) { 873 if (CostKind != TTI::TCK_RecipThroughput) 874 return BaseT::getCmpSelInstrCost(Opcode, ValTy, CondTy, VecPred, CostKind); 875 876 if (!ValTy->isVectorTy()) { 877 switch (Opcode) { 878 case Instruction::ICmp: { 879 // A loaded value compared with 0 with multiple users becomes Load and 880 // Test. The load is then not foldable, so return 0 cost for the ICmp. 881 unsigned ScalarBits = ValTy->getScalarSizeInBits(); 882 if (I != nullptr && ScalarBits >= 32) 883 if (LoadInst *Ld = dyn_cast<LoadInst>(I->getOperand(0))) 884 if (const ConstantInt *C = dyn_cast<ConstantInt>(I->getOperand(1))) 885 if (!Ld->hasOneUse() && Ld->getParent() == I->getParent() && 886 C->isZero()) 887 return 0; 888 889 unsigned Cost = 1; 890 if (ValTy->isIntegerTy() && ValTy->getScalarSizeInBits() <= 16) 891 Cost += (I != nullptr ? getOperandsExtensionCost(I) : 2); 892 return Cost; 893 } 894 case Instruction::Select: 895 if (ValTy->isFloatingPointTy()) 896 return 4; // No load on condition for FP - costs a conditional jump. 897 return 1; // Load On Condition / Select Register. 898 } 899 } 900 else if (ST->hasVector()) { 901 unsigned VF = cast<FixedVectorType>(ValTy)->getNumElements(); 902 903 // Called with a compare instruction. 904 if (Opcode == Instruction::ICmp || Opcode == Instruction::FCmp) { 905 unsigned PredicateExtraCost = 0; 906 if (I != nullptr) { 907 // Some predicates cost one or two extra instructions. 908 switch (cast<CmpInst>(I)->getPredicate()) { 909 case CmpInst::Predicate::ICMP_NE: 910 case CmpInst::Predicate::ICMP_UGE: 911 case CmpInst::Predicate::ICMP_ULE: 912 case CmpInst::Predicate::ICMP_SGE: 913 case CmpInst::Predicate::ICMP_SLE: 914 PredicateExtraCost = 1; 915 break; 916 case CmpInst::Predicate::FCMP_ONE: 917 case CmpInst::Predicate::FCMP_ORD: 918 case CmpInst::Predicate::FCMP_UEQ: 919 case CmpInst::Predicate::FCMP_UNO: 920 PredicateExtraCost = 2; 921 break; 922 default: 923 break; 924 } 925 } 926 927 // Float is handled with 2*vmr[lh]f + 2*vldeb + vfchdb for each pair of 928 // floats. FIXME: <2 x float> generates same code as <4 x float>. 929 unsigned CmpCostPerVector = (ValTy->getScalarType()->isFloatTy() ? 10 : 1); 930 unsigned NumVecs_cmp = getNumVectorRegs(ValTy); 931 932 unsigned Cost = (NumVecs_cmp * (CmpCostPerVector + PredicateExtraCost)); 933 return Cost; 934 } 935 else { // Called with a select instruction. 936 assert (Opcode == Instruction::Select); 937 938 // We can figure out the extra cost of packing / unpacking if the 939 // instruction was passed and the compare instruction is found. 940 unsigned PackCost = 0; 941 Type *CmpOpTy = ((I != nullptr) ? getCmpOpsType(I, VF) : nullptr); 942 if (CmpOpTy != nullptr) 943 PackCost = 944 getVectorBitmaskConversionCost(CmpOpTy, ValTy); 945 946 return getNumVectorRegs(ValTy) /*vsel*/ + PackCost; 947 } 948 } 949 950 return BaseT::getCmpSelInstrCost(Opcode, ValTy, CondTy, VecPred, CostKind); 951 } 952 953 int SystemZTTIImpl:: 954 getVectorInstrCost(unsigned Opcode, Type *Val, unsigned Index) { 955 // vlvgp will insert two grs into a vector register, so only count half the 956 // number of instructions. 957 if (Opcode == Instruction::InsertElement && Val->isIntOrIntVectorTy(64)) 958 return ((Index % 2 == 0) ? 1 : 0); 959 960 if (Opcode == Instruction::ExtractElement) { 961 int Cost = ((getScalarSizeInBits(Val) == 1) ? 2 /*+test-under-mask*/ : 1); 962 963 // Give a slight penalty for moving out of vector pipeline to FXU unit. 964 if (Index == 0 && Val->isIntOrIntVectorTy()) 965 Cost += 1; 966 967 return Cost; 968 } 969 970 return BaseT::getVectorInstrCost(Opcode, Val, Index); 971 } 972 973 // Check if a load may be folded as a memory operand in its user. 974 bool SystemZTTIImpl:: 975 isFoldableLoad(const LoadInst *Ld, const Instruction *&FoldedValue) { 976 if (!Ld->hasOneUse()) 977 return false; 978 FoldedValue = Ld; 979 const Instruction *UserI = cast<Instruction>(*Ld->user_begin()); 980 unsigned LoadedBits = getScalarSizeInBits(Ld->getType()); 981 unsigned TruncBits = 0; 982 unsigned SExtBits = 0; 983 unsigned ZExtBits = 0; 984 if (UserI->hasOneUse()) { 985 unsigned UserBits = UserI->getType()->getScalarSizeInBits(); 986 if (isa<TruncInst>(UserI)) 987 TruncBits = UserBits; 988 else if (isa<SExtInst>(UserI)) 989 SExtBits = UserBits; 990 else if (isa<ZExtInst>(UserI)) 991 ZExtBits = UserBits; 992 } 993 if (TruncBits || SExtBits || ZExtBits) { 994 FoldedValue = UserI; 995 UserI = cast<Instruction>(*UserI->user_begin()); 996 // Load (single use) -> trunc/extend (single use) -> UserI 997 } 998 if ((UserI->getOpcode() == Instruction::Sub || 999 UserI->getOpcode() == Instruction::SDiv || 1000 UserI->getOpcode() == Instruction::UDiv) && 1001 UserI->getOperand(1) != FoldedValue) 1002 return false; // Not commutative, only RHS foldable. 1003 // LoadOrTruncBits holds the number of effectively loaded bits, but 0 if an 1004 // extension was made of the load. 1005 unsigned LoadOrTruncBits = 1006 ((SExtBits || ZExtBits) ? 0 : (TruncBits ? TruncBits : LoadedBits)); 1007 switch (UserI->getOpcode()) { 1008 case Instruction::Add: // SE: 16->32, 16/32->64, z14:16->64. ZE: 32->64 1009 case Instruction::Sub: 1010 case Instruction::ICmp: 1011 if (LoadedBits == 32 && ZExtBits == 64) 1012 return true; 1013 LLVM_FALLTHROUGH; 1014 case Instruction::Mul: // SE: 16->32, 32->64, z14:16->64 1015 if (UserI->getOpcode() != Instruction::ICmp) { 1016 if (LoadedBits == 16 && 1017 (SExtBits == 32 || 1018 (SExtBits == 64 && ST->hasMiscellaneousExtensions2()))) 1019 return true; 1020 if (LoadOrTruncBits == 16) 1021 return true; 1022 } 1023 LLVM_FALLTHROUGH; 1024 case Instruction::SDiv:// SE: 32->64 1025 if (LoadedBits == 32 && SExtBits == 64) 1026 return true; 1027 LLVM_FALLTHROUGH; 1028 case Instruction::UDiv: 1029 case Instruction::And: 1030 case Instruction::Or: 1031 case Instruction::Xor: 1032 // This also makes sense for float operations, but disabled for now due 1033 // to regressions. 1034 // case Instruction::FCmp: 1035 // case Instruction::FAdd: 1036 // case Instruction::FSub: 1037 // case Instruction::FMul: 1038 // case Instruction::FDiv: 1039 1040 // All possible extensions of memory checked above. 1041 1042 // Comparison between memory and immediate. 1043 if (UserI->getOpcode() == Instruction::ICmp) 1044 if (ConstantInt *CI = dyn_cast<ConstantInt>(UserI->getOperand(1))) 1045 if (CI->getValue().isIntN(16)) 1046 return true; 1047 return (LoadOrTruncBits == 32 || LoadOrTruncBits == 64); 1048 break; 1049 } 1050 return false; 1051 } 1052 1053 static bool isBswapIntrinsicCall(const Value *V) { 1054 if (const Instruction *I = dyn_cast<Instruction>(V)) 1055 if (auto *CI = dyn_cast<CallInst>(I)) 1056 if (auto *F = CI->getCalledFunction()) 1057 if (F->getIntrinsicID() == Intrinsic::bswap) 1058 return true; 1059 return false; 1060 } 1061 1062 int SystemZTTIImpl::getMemoryOpCost(unsigned Opcode, Type *Src, 1063 MaybeAlign Alignment, unsigned AddressSpace, 1064 TTI::TargetCostKind CostKind, 1065 const Instruction *I) { 1066 assert(!Src->isVoidTy() && "Invalid type"); 1067 1068 // TODO: Handle other cost kinds. 1069 if (CostKind != TTI::TCK_RecipThroughput) 1070 return 1; 1071 1072 if (!Src->isVectorTy() && Opcode == Instruction::Load && I != nullptr) { 1073 // Store the load or its truncated or extended value in FoldedValue. 1074 const Instruction *FoldedValue = nullptr; 1075 if (isFoldableLoad(cast<LoadInst>(I), FoldedValue)) { 1076 const Instruction *UserI = cast<Instruction>(*FoldedValue->user_begin()); 1077 assert (UserI->getNumOperands() == 2 && "Expected a binop."); 1078 1079 // UserI can't fold two loads, so in that case return 0 cost only 1080 // half of the time. 1081 for (unsigned i = 0; i < 2; ++i) { 1082 if (UserI->getOperand(i) == FoldedValue) 1083 continue; 1084 1085 if (Instruction *OtherOp = dyn_cast<Instruction>(UserI->getOperand(i))){ 1086 LoadInst *OtherLoad = dyn_cast<LoadInst>(OtherOp); 1087 if (!OtherLoad && 1088 (isa<TruncInst>(OtherOp) || isa<SExtInst>(OtherOp) || 1089 isa<ZExtInst>(OtherOp))) 1090 OtherLoad = dyn_cast<LoadInst>(OtherOp->getOperand(0)); 1091 if (OtherLoad && isFoldableLoad(OtherLoad, FoldedValue/*dummy*/)) 1092 return i == 0; // Both operands foldable. 1093 } 1094 } 1095 1096 return 0; // Only I is foldable in user. 1097 } 1098 } 1099 1100 unsigned NumOps = 1101 (Src->isVectorTy() ? getNumVectorRegs(Src) : getNumberOfParts(Src)); 1102 1103 // Store/Load reversed saves one instruction. 1104 if (((!Src->isVectorTy() && NumOps == 1) || ST->hasVectorEnhancements2()) && 1105 I != nullptr) { 1106 if (Opcode == Instruction::Load && I->hasOneUse()) { 1107 const Instruction *LdUser = cast<Instruction>(*I->user_begin()); 1108 // In case of load -> bswap -> store, return normal cost for the load. 1109 if (isBswapIntrinsicCall(LdUser) && 1110 (!LdUser->hasOneUse() || !isa<StoreInst>(*LdUser->user_begin()))) 1111 return 0; 1112 } 1113 else if (const StoreInst *SI = dyn_cast<StoreInst>(I)) { 1114 const Value *StoredVal = SI->getValueOperand(); 1115 if (StoredVal->hasOneUse() && isBswapIntrinsicCall(StoredVal)) 1116 return 0; 1117 } 1118 } 1119 1120 if (Src->getScalarSizeInBits() == 128) 1121 // 128 bit scalars are held in a pair of two 64 bit registers. 1122 NumOps *= 2; 1123 1124 return NumOps; 1125 } 1126 1127 // The generic implementation of getInterleavedMemoryOpCost() is based on 1128 // adding costs of the memory operations plus all the extracts and inserts 1129 // needed for using / defining the vector operands. The SystemZ version does 1130 // roughly the same but bases the computations on vector permutations 1131 // instead. 1132 int SystemZTTIImpl::getInterleavedMemoryOpCost( 1133 unsigned Opcode, Type *VecTy, unsigned Factor, ArrayRef<unsigned> Indices, 1134 Align Alignment, unsigned AddressSpace, TTI::TargetCostKind CostKind, 1135 bool UseMaskForCond, bool UseMaskForGaps) { 1136 if (UseMaskForCond || UseMaskForGaps) 1137 return BaseT::getInterleavedMemoryOpCost(Opcode, VecTy, Factor, Indices, 1138 Alignment, AddressSpace, CostKind, 1139 UseMaskForCond, UseMaskForGaps); 1140 assert(isa<VectorType>(VecTy) && 1141 "Expect a vector type for interleaved memory op"); 1142 1143 // Return the ceiling of dividing A by B. 1144 auto ceil = [](unsigned A, unsigned B) { return (A + B - 1) / B; }; 1145 1146 unsigned NumElts = cast<FixedVectorType>(VecTy)->getNumElements(); 1147 assert(Factor > 1 && NumElts % Factor == 0 && "Invalid interleave factor"); 1148 unsigned VF = NumElts / Factor; 1149 unsigned NumEltsPerVecReg = (128U / getScalarSizeInBits(VecTy)); 1150 unsigned NumVectorMemOps = getNumVectorRegs(VecTy); 1151 unsigned NumPermutes = 0; 1152 1153 if (Opcode == Instruction::Load) { 1154 // Loading interleave groups may have gaps, which may mean fewer 1155 // loads. Find out how many vectors will be loaded in total, and in how 1156 // many of them each value will be in. 1157 BitVector UsedInsts(NumVectorMemOps, false); 1158 std::vector<BitVector> ValueVecs(Factor, BitVector(NumVectorMemOps, false)); 1159 for (unsigned Index : Indices) 1160 for (unsigned Elt = 0; Elt < VF; ++Elt) { 1161 unsigned Vec = (Index + Elt * Factor) / NumEltsPerVecReg; 1162 UsedInsts.set(Vec); 1163 ValueVecs[Index].set(Vec); 1164 } 1165 NumVectorMemOps = UsedInsts.count(); 1166 1167 for (unsigned Index : Indices) { 1168 // Estimate that each loaded source vector containing this Index 1169 // requires one operation, except that vperm can handle two input 1170 // registers first time for each dst vector. 1171 unsigned NumSrcVecs = ValueVecs[Index].count(); 1172 unsigned NumDstVecs = ceil(VF * getScalarSizeInBits(VecTy), 128U); 1173 assert (NumSrcVecs >= NumDstVecs && "Expected at least as many sources"); 1174 NumPermutes += std::max(1U, NumSrcVecs - NumDstVecs); 1175 } 1176 } else { 1177 // Estimate the permutes for each stored vector as the smaller of the 1178 // number of elements and the number of source vectors. Subtract one per 1179 // dst vector for vperm (S.A.). 1180 unsigned NumSrcVecs = std::min(NumEltsPerVecReg, Factor); 1181 unsigned NumDstVecs = NumVectorMemOps; 1182 assert (NumSrcVecs > 1 && "Expected at least two source vectors."); 1183 NumPermutes += (NumDstVecs * NumSrcVecs) - NumDstVecs; 1184 } 1185 1186 // Cost of load/store operations and the permutations needed. 1187 return NumVectorMemOps + NumPermutes; 1188 } 1189 1190 static int getVectorIntrinsicInstrCost(Intrinsic::ID ID, Type *RetTy) { 1191 if (RetTy->isVectorTy() && ID == Intrinsic::bswap) 1192 return getNumVectorRegs(RetTy); // VPERM 1193 return -1; 1194 } 1195 1196 InstructionCost 1197 SystemZTTIImpl::getIntrinsicInstrCost(const IntrinsicCostAttributes &ICA, 1198 TTI::TargetCostKind CostKind) { 1199 InstructionCost Cost = 1200 getVectorIntrinsicInstrCost(ICA.getID(), ICA.getReturnType()); 1201 if (Cost != -1) 1202 return Cost; 1203 return BaseT::getIntrinsicInstrCost(ICA, CostKind); 1204 } 1205