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 int SystemZTTIImpl::getCastInstrCost(unsigned Opcode, Type *Dst, Type *Src, 717 TTI::CastContextHint CCH, 718 TTI::TargetCostKind CostKind, 719 const Instruction *I) { 720 // FIXME: Can the logic below also be used for these cost kinds? 721 if (CostKind == TTI::TCK_CodeSize || CostKind == TTI::TCK_SizeAndLatency) { 722 int BaseCost = BaseT::getCastInstrCost(Opcode, Dst, Src, CCH, CostKind, I); 723 return BaseCost == 0 ? BaseCost : 1; 724 } 725 726 unsigned DstScalarBits = Dst->getScalarSizeInBits(); 727 unsigned SrcScalarBits = Src->getScalarSizeInBits(); 728 729 if (!Src->isVectorTy()) { 730 assert (!Dst->isVectorTy()); 731 732 if (Opcode == Instruction::SIToFP || Opcode == Instruction::UIToFP) { 733 if (SrcScalarBits >= 32 || 734 (I != nullptr && isa<LoadInst>(I->getOperand(0)))) 735 return 1; 736 return SrcScalarBits > 1 ? 2 /*i8/i16 extend*/ : 5 /*branch seq.*/; 737 } 738 739 if ((Opcode == Instruction::ZExt || Opcode == Instruction::SExt) && 740 Src->isIntegerTy(1)) { 741 if (ST->hasLoadStoreOnCond2()) 742 return 2; // li 0; loc 1 743 744 // This should be extension of a compare i1 result, which is done with 745 // ipm and a varying sequence of instructions. 746 unsigned Cost = 0; 747 if (Opcode == Instruction::SExt) 748 Cost = (DstScalarBits < 64 ? 3 : 4); 749 if (Opcode == Instruction::ZExt) 750 Cost = 3; 751 Type *CmpOpTy = ((I != nullptr) ? getCmpOpsType(I) : nullptr); 752 if (CmpOpTy != nullptr && CmpOpTy->isFloatingPointTy()) 753 // If operands of an fp-type was compared, this costs +1. 754 Cost++; 755 return Cost; 756 } 757 } 758 else if (ST->hasVector()) { 759 // Vector to scalar cast. 760 auto *SrcVecTy = cast<FixedVectorType>(Src); 761 auto *DstVecTy = dyn_cast<FixedVectorType>(Dst); 762 if (!DstVecTy) { 763 // TODO: tune vector-to-scalar cast. 764 return BaseT::getCastInstrCost(Opcode, Dst, Src, CCH, CostKind, I); 765 } 766 unsigned VF = SrcVecTy->getNumElements(); 767 unsigned NumDstVectors = getNumVectorRegs(Dst); 768 unsigned NumSrcVectors = getNumVectorRegs(Src); 769 770 if (Opcode == Instruction::Trunc) { 771 if (Src->getScalarSizeInBits() == Dst->getScalarSizeInBits()) 772 return 0; // Check for NOOP conversions. 773 return getVectorTruncCost(Src, Dst); 774 } 775 776 if (Opcode == Instruction::ZExt || Opcode == Instruction::SExt) { 777 if (SrcScalarBits >= 8) { 778 // ZExt/SExt will be handled with one unpack per doubling of width. 779 unsigned NumUnpacks = getElSizeLog2Diff(Src, Dst); 780 781 // For types that spans multiple vector registers, some additional 782 // instructions are used to setup the unpacking. 783 unsigned NumSrcVectorOps = 784 (NumUnpacks > 1 ? (NumDstVectors - NumSrcVectors) 785 : (NumDstVectors / 2)); 786 787 return (NumUnpacks * NumDstVectors) + NumSrcVectorOps; 788 } 789 else if (SrcScalarBits == 1) 790 return getBoolVecToIntConversionCost(Opcode, Dst, I); 791 } 792 793 if (Opcode == Instruction::SIToFP || Opcode == Instruction::UIToFP || 794 Opcode == Instruction::FPToSI || Opcode == Instruction::FPToUI) { 795 // TODO: Fix base implementation which could simplify things a bit here 796 // (seems to miss on differentiating on scalar/vector types). 797 798 // Only 64 bit vector conversions are natively supported before z15. 799 if (DstScalarBits == 64 || ST->hasVectorEnhancements2()) { 800 if (SrcScalarBits == DstScalarBits) 801 return NumDstVectors; 802 803 if (SrcScalarBits == 1) 804 return getBoolVecToIntConversionCost(Opcode, Dst, I) + NumDstVectors; 805 } 806 807 // Return the cost of multiple scalar invocation plus the cost of 808 // inserting and extracting the values. Base implementation does not 809 // realize float->int gets scalarized. 810 unsigned ScalarCost = getCastInstrCost( 811 Opcode, Dst->getScalarType(), Src->getScalarType(), CCH, CostKind); 812 unsigned TotCost = VF * ScalarCost; 813 bool NeedsInserts = true, NeedsExtracts = true; 814 // FP128 registers do not get inserted or extracted. 815 if (DstScalarBits == 128 && 816 (Opcode == Instruction::SIToFP || Opcode == Instruction::UIToFP)) 817 NeedsInserts = false; 818 if (SrcScalarBits == 128 && 819 (Opcode == Instruction::FPToSI || Opcode == Instruction::FPToUI)) 820 NeedsExtracts = false; 821 822 TotCost += getScalarizationOverhead(SrcVecTy, false, NeedsExtracts); 823 TotCost += getScalarizationOverhead(DstVecTy, NeedsInserts, false); 824 825 // FIXME: VF 2 for float<->i32 is currently just as expensive as for VF 4. 826 if (VF == 2 && SrcScalarBits == 32 && DstScalarBits == 32) 827 TotCost *= 2; 828 829 return TotCost; 830 } 831 832 if (Opcode == Instruction::FPTrunc) { 833 if (SrcScalarBits == 128) // fp128 -> double/float + inserts of elements. 834 return VF /*ldxbr/lexbr*/ + 835 getScalarizationOverhead(DstVecTy, true, false); 836 else // double -> float 837 return VF / 2 /*vledb*/ + std::max(1U, VF / 4 /*vperm*/); 838 } 839 840 if (Opcode == Instruction::FPExt) { 841 if (SrcScalarBits == 32 && DstScalarBits == 64) { 842 // float -> double is very rare and currently unoptimized. Instead of 843 // using vldeb, which can do two at a time, all conversions are 844 // scalarized. 845 return VF * 2; 846 } 847 // -> fp128. VF * lxdb/lxeb + extraction of elements. 848 return VF + getScalarizationOverhead(SrcVecTy, false, true); 849 } 850 } 851 852 return BaseT::getCastInstrCost(Opcode, Dst, Src, CCH, CostKind, I); 853 } 854 855 // Scalar i8 / i16 operations will typically be made after first extending 856 // the operands to i32. 857 static unsigned getOperandsExtensionCost(const Instruction *I) { 858 unsigned ExtCost = 0; 859 for (Value *Op : I->operands()) 860 // A load of i8 or i16 sign/zero extends to i32. 861 if (!isa<LoadInst>(Op) && !isa<ConstantInt>(Op)) 862 ExtCost++; 863 864 return ExtCost; 865 } 866 867 int SystemZTTIImpl::getCmpSelInstrCost(unsigned Opcode, Type *ValTy, 868 Type *CondTy, CmpInst::Predicate VecPred, 869 TTI::TargetCostKind CostKind, 870 const Instruction *I) { 871 if (CostKind != TTI::TCK_RecipThroughput) 872 return BaseT::getCmpSelInstrCost(Opcode, ValTy, CondTy, VecPred, CostKind); 873 874 if (!ValTy->isVectorTy()) { 875 switch (Opcode) { 876 case Instruction::ICmp: { 877 // A loaded value compared with 0 with multiple users becomes Load and 878 // Test. The load is then not foldable, so return 0 cost for the ICmp. 879 unsigned ScalarBits = ValTy->getScalarSizeInBits(); 880 if (I != nullptr && ScalarBits >= 32) 881 if (LoadInst *Ld = dyn_cast<LoadInst>(I->getOperand(0))) 882 if (const ConstantInt *C = dyn_cast<ConstantInt>(I->getOperand(1))) 883 if (!Ld->hasOneUse() && Ld->getParent() == I->getParent() && 884 C->isZero()) 885 return 0; 886 887 unsigned Cost = 1; 888 if (ValTy->isIntegerTy() && ValTy->getScalarSizeInBits() <= 16) 889 Cost += (I != nullptr ? getOperandsExtensionCost(I) : 2); 890 return Cost; 891 } 892 case Instruction::Select: 893 if (ValTy->isFloatingPointTy()) 894 return 4; // No load on condition for FP - costs a conditional jump. 895 return 1; // Load On Condition / Select Register. 896 } 897 } 898 else if (ST->hasVector()) { 899 unsigned VF = cast<FixedVectorType>(ValTy)->getNumElements(); 900 901 // Called with a compare instruction. 902 if (Opcode == Instruction::ICmp || Opcode == Instruction::FCmp) { 903 unsigned PredicateExtraCost = 0; 904 if (I != nullptr) { 905 // Some predicates cost one or two extra instructions. 906 switch (cast<CmpInst>(I)->getPredicate()) { 907 case CmpInst::Predicate::ICMP_NE: 908 case CmpInst::Predicate::ICMP_UGE: 909 case CmpInst::Predicate::ICMP_ULE: 910 case CmpInst::Predicate::ICMP_SGE: 911 case CmpInst::Predicate::ICMP_SLE: 912 PredicateExtraCost = 1; 913 break; 914 case CmpInst::Predicate::FCMP_ONE: 915 case CmpInst::Predicate::FCMP_ORD: 916 case CmpInst::Predicate::FCMP_UEQ: 917 case CmpInst::Predicate::FCMP_UNO: 918 PredicateExtraCost = 2; 919 break; 920 default: 921 break; 922 } 923 } 924 925 // Float is handled with 2*vmr[lh]f + 2*vldeb + vfchdb for each pair of 926 // floats. FIXME: <2 x float> generates same code as <4 x float>. 927 unsigned CmpCostPerVector = (ValTy->getScalarType()->isFloatTy() ? 10 : 1); 928 unsigned NumVecs_cmp = getNumVectorRegs(ValTy); 929 930 unsigned Cost = (NumVecs_cmp * (CmpCostPerVector + PredicateExtraCost)); 931 return Cost; 932 } 933 else { // Called with a select instruction. 934 assert (Opcode == Instruction::Select); 935 936 // We can figure out the extra cost of packing / unpacking if the 937 // instruction was passed and the compare instruction is found. 938 unsigned PackCost = 0; 939 Type *CmpOpTy = ((I != nullptr) ? getCmpOpsType(I, VF) : nullptr); 940 if (CmpOpTy != nullptr) 941 PackCost = 942 getVectorBitmaskConversionCost(CmpOpTy, ValTy); 943 944 return getNumVectorRegs(ValTy) /*vsel*/ + PackCost; 945 } 946 } 947 948 return BaseT::getCmpSelInstrCost(Opcode, ValTy, CondTy, VecPred, CostKind); 949 } 950 951 int SystemZTTIImpl:: 952 getVectorInstrCost(unsigned Opcode, Type *Val, unsigned Index) { 953 // vlvgp will insert two grs into a vector register, so only count half the 954 // number of instructions. 955 if (Opcode == Instruction::InsertElement && Val->isIntOrIntVectorTy(64)) 956 return ((Index % 2 == 0) ? 1 : 0); 957 958 if (Opcode == Instruction::ExtractElement) { 959 int Cost = ((getScalarSizeInBits(Val) == 1) ? 2 /*+test-under-mask*/ : 1); 960 961 // Give a slight penalty for moving out of vector pipeline to FXU unit. 962 if (Index == 0 && Val->isIntOrIntVectorTy()) 963 Cost += 1; 964 965 return Cost; 966 } 967 968 return BaseT::getVectorInstrCost(Opcode, Val, Index); 969 } 970 971 // Check if a load may be folded as a memory operand in its user. 972 bool SystemZTTIImpl:: 973 isFoldableLoad(const LoadInst *Ld, const Instruction *&FoldedValue) { 974 if (!Ld->hasOneUse()) 975 return false; 976 FoldedValue = Ld; 977 const Instruction *UserI = cast<Instruction>(*Ld->user_begin()); 978 unsigned LoadedBits = getScalarSizeInBits(Ld->getType()); 979 unsigned TruncBits = 0; 980 unsigned SExtBits = 0; 981 unsigned ZExtBits = 0; 982 if (UserI->hasOneUse()) { 983 unsigned UserBits = UserI->getType()->getScalarSizeInBits(); 984 if (isa<TruncInst>(UserI)) 985 TruncBits = UserBits; 986 else if (isa<SExtInst>(UserI)) 987 SExtBits = UserBits; 988 else if (isa<ZExtInst>(UserI)) 989 ZExtBits = UserBits; 990 } 991 if (TruncBits || SExtBits || ZExtBits) { 992 FoldedValue = UserI; 993 UserI = cast<Instruction>(*UserI->user_begin()); 994 // Load (single use) -> trunc/extend (single use) -> UserI 995 } 996 if ((UserI->getOpcode() == Instruction::Sub || 997 UserI->getOpcode() == Instruction::SDiv || 998 UserI->getOpcode() == Instruction::UDiv) && 999 UserI->getOperand(1) != FoldedValue) 1000 return false; // Not commutative, only RHS foldable. 1001 // LoadOrTruncBits holds the number of effectively loaded bits, but 0 if an 1002 // extension was made of the load. 1003 unsigned LoadOrTruncBits = 1004 ((SExtBits || ZExtBits) ? 0 : (TruncBits ? TruncBits : LoadedBits)); 1005 switch (UserI->getOpcode()) { 1006 case Instruction::Add: // SE: 16->32, 16/32->64, z14:16->64. ZE: 32->64 1007 case Instruction::Sub: 1008 case Instruction::ICmp: 1009 if (LoadedBits == 32 && ZExtBits == 64) 1010 return true; 1011 LLVM_FALLTHROUGH; 1012 case Instruction::Mul: // SE: 16->32, 32->64, z14:16->64 1013 if (UserI->getOpcode() != Instruction::ICmp) { 1014 if (LoadedBits == 16 && 1015 (SExtBits == 32 || 1016 (SExtBits == 64 && ST->hasMiscellaneousExtensions2()))) 1017 return true; 1018 if (LoadOrTruncBits == 16) 1019 return true; 1020 } 1021 LLVM_FALLTHROUGH; 1022 case Instruction::SDiv:// SE: 32->64 1023 if (LoadedBits == 32 && SExtBits == 64) 1024 return true; 1025 LLVM_FALLTHROUGH; 1026 case Instruction::UDiv: 1027 case Instruction::And: 1028 case Instruction::Or: 1029 case Instruction::Xor: 1030 // This also makes sense for float operations, but disabled for now due 1031 // to regressions. 1032 // case Instruction::FCmp: 1033 // case Instruction::FAdd: 1034 // case Instruction::FSub: 1035 // case Instruction::FMul: 1036 // case Instruction::FDiv: 1037 1038 // All possible extensions of memory checked above. 1039 1040 // Comparison between memory and immediate. 1041 if (UserI->getOpcode() == Instruction::ICmp) 1042 if (ConstantInt *CI = dyn_cast<ConstantInt>(UserI->getOperand(1))) 1043 if (CI->getValue().isIntN(16)) 1044 return true; 1045 return (LoadOrTruncBits == 32 || LoadOrTruncBits == 64); 1046 break; 1047 } 1048 return false; 1049 } 1050 1051 static bool isBswapIntrinsicCall(const Value *V) { 1052 if (const Instruction *I = dyn_cast<Instruction>(V)) 1053 if (auto *CI = dyn_cast<CallInst>(I)) 1054 if (auto *F = CI->getCalledFunction()) 1055 if (F->getIntrinsicID() == Intrinsic::bswap) 1056 return true; 1057 return false; 1058 } 1059 1060 int SystemZTTIImpl::getMemoryOpCost(unsigned Opcode, Type *Src, 1061 MaybeAlign Alignment, unsigned AddressSpace, 1062 TTI::TargetCostKind CostKind, 1063 const Instruction *I) { 1064 assert(!Src->isVoidTy() && "Invalid type"); 1065 1066 // TODO: Handle other cost kinds. 1067 if (CostKind != TTI::TCK_RecipThroughput) 1068 return 1; 1069 1070 if (!Src->isVectorTy() && Opcode == Instruction::Load && I != nullptr) { 1071 // Store the load or its truncated or extended value in FoldedValue. 1072 const Instruction *FoldedValue = nullptr; 1073 if (isFoldableLoad(cast<LoadInst>(I), FoldedValue)) { 1074 const Instruction *UserI = cast<Instruction>(*FoldedValue->user_begin()); 1075 assert (UserI->getNumOperands() == 2 && "Expected a binop."); 1076 1077 // UserI can't fold two loads, so in that case return 0 cost only 1078 // half of the time. 1079 for (unsigned i = 0; i < 2; ++i) { 1080 if (UserI->getOperand(i) == FoldedValue) 1081 continue; 1082 1083 if (Instruction *OtherOp = dyn_cast<Instruction>(UserI->getOperand(i))){ 1084 LoadInst *OtherLoad = dyn_cast<LoadInst>(OtherOp); 1085 if (!OtherLoad && 1086 (isa<TruncInst>(OtherOp) || isa<SExtInst>(OtherOp) || 1087 isa<ZExtInst>(OtherOp))) 1088 OtherLoad = dyn_cast<LoadInst>(OtherOp->getOperand(0)); 1089 if (OtherLoad && isFoldableLoad(OtherLoad, FoldedValue/*dummy*/)) 1090 return i == 0; // Both operands foldable. 1091 } 1092 } 1093 1094 return 0; // Only I is foldable in user. 1095 } 1096 } 1097 1098 unsigned NumOps = 1099 (Src->isVectorTy() ? getNumVectorRegs(Src) : getNumberOfParts(Src)); 1100 1101 // Store/Load reversed saves one instruction. 1102 if (((!Src->isVectorTy() && NumOps == 1) || ST->hasVectorEnhancements2()) && 1103 I != nullptr) { 1104 if (Opcode == Instruction::Load && I->hasOneUse()) { 1105 const Instruction *LdUser = cast<Instruction>(*I->user_begin()); 1106 // In case of load -> bswap -> store, return normal cost for the load. 1107 if (isBswapIntrinsicCall(LdUser) && 1108 (!LdUser->hasOneUse() || !isa<StoreInst>(*LdUser->user_begin()))) 1109 return 0; 1110 } 1111 else if (const StoreInst *SI = dyn_cast<StoreInst>(I)) { 1112 const Value *StoredVal = SI->getValueOperand(); 1113 if (StoredVal->hasOneUse() && isBswapIntrinsicCall(StoredVal)) 1114 return 0; 1115 } 1116 } 1117 1118 if (Src->getScalarSizeInBits() == 128) 1119 // 128 bit scalars are held in a pair of two 64 bit registers. 1120 NumOps *= 2; 1121 1122 return NumOps; 1123 } 1124 1125 // The generic implementation of getInterleavedMemoryOpCost() is based on 1126 // adding costs of the memory operations plus all the extracts and inserts 1127 // needed for using / defining the vector operands. The SystemZ version does 1128 // roughly the same but bases the computations on vector permutations 1129 // instead. 1130 int SystemZTTIImpl::getInterleavedMemoryOpCost( 1131 unsigned Opcode, Type *VecTy, unsigned Factor, ArrayRef<unsigned> Indices, 1132 Align Alignment, unsigned AddressSpace, TTI::TargetCostKind CostKind, 1133 bool UseMaskForCond, bool UseMaskForGaps) { 1134 if (UseMaskForCond || UseMaskForGaps) 1135 return BaseT::getInterleavedMemoryOpCost(Opcode, VecTy, Factor, Indices, 1136 Alignment, AddressSpace, CostKind, 1137 UseMaskForCond, UseMaskForGaps); 1138 assert(isa<VectorType>(VecTy) && 1139 "Expect a vector type for interleaved memory op"); 1140 1141 // Return the ceiling of dividing A by B. 1142 auto ceil = [](unsigned A, unsigned B) { return (A + B - 1) / B; }; 1143 1144 unsigned NumElts = cast<FixedVectorType>(VecTy)->getNumElements(); 1145 assert(Factor > 1 && NumElts % Factor == 0 && "Invalid interleave factor"); 1146 unsigned VF = NumElts / Factor; 1147 unsigned NumEltsPerVecReg = (128U / getScalarSizeInBits(VecTy)); 1148 unsigned NumVectorMemOps = getNumVectorRegs(VecTy); 1149 unsigned NumPermutes = 0; 1150 1151 if (Opcode == Instruction::Load) { 1152 // Loading interleave groups may have gaps, which may mean fewer 1153 // loads. Find out how many vectors will be loaded in total, and in how 1154 // many of them each value will be in. 1155 BitVector UsedInsts(NumVectorMemOps, false); 1156 std::vector<BitVector> ValueVecs(Factor, BitVector(NumVectorMemOps, false)); 1157 for (unsigned Index : Indices) 1158 for (unsigned Elt = 0; Elt < VF; ++Elt) { 1159 unsigned Vec = (Index + Elt * Factor) / NumEltsPerVecReg; 1160 UsedInsts.set(Vec); 1161 ValueVecs[Index].set(Vec); 1162 } 1163 NumVectorMemOps = UsedInsts.count(); 1164 1165 for (unsigned Index : Indices) { 1166 // Estimate that each loaded source vector containing this Index 1167 // requires one operation, except that vperm can handle two input 1168 // registers first time for each dst vector. 1169 unsigned NumSrcVecs = ValueVecs[Index].count(); 1170 unsigned NumDstVecs = ceil(VF * getScalarSizeInBits(VecTy), 128U); 1171 assert (NumSrcVecs >= NumDstVecs && "Expected at least as many sources"); 1172 NumPermutes += std::max(1U, NumSrcVecs - NumDstVecs); 1173 } 1174 } else { 1175 // Estimate the permutes for each stored vector as the smaller of the 1176 // number of elements and the number of source vectors. Subtract one per 1177 // dst vector for vperm (S.A.). 1178 unsigned NumSrcVecs = std::min(NumEltsPerVecReg, Factor); 1179 unsigned NumDstVecs = NumVectorMemOps; 1180 assert (NumSrcVecs > 1 && "Expected at least two source vectors."); 1181 NumPermutes += (NumDstVecs * NumSrcVecs) - NumDstVecs; 1182 } 1183 1184 // Cost of load/store operations and the permutations needed. 1185 return NumVectorMemOps + NumPermutes; 1186 } 1187 1188 static int getVectorIntrinsicInstrCost(Intrinsic::ID ID, Type *RetTy) { 1189 if (RetTy->isVectorTy() && ID == Intrinsic::bswap) 1190 return getNumVectorRegs(RetTy); // VPERM 1191 return -1; 1192 } 1193 1194 InstructionCost 1195 SystemZTTIImpl::getIntrinsicInstrCost(const IntrinsicCostAttributes &ICA, 1196 TTI::TargetCostKind CostKind) { 1197 InstructionCost Cost = 1198 getVectorIntrinsicInstrCost(ICA.getID(), ICA.getReturnType()); 1199 if (Cost != -1) 1200 return Cost; 1201 return BaseT::getIntrinsicInstrCost(ICA, CostKind); 1202 } 1203