1 //===-- LanaiTargetTransformInfo.h - Lanai specific TTI ---------*- C++ -*-===// 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 a TargetTransformInfo::Concept conforming object specific to the 10 // Lanai target machine. It uses the target's detailed information to 11 // provide more precise answers to certain TTI queries, while letting the 12 // target independent and default TTI implementations handle the rest. 13 // 14 //===----------------------------------------------------------------------===// 15 16 #ifndef LLVM_LIB_TARGET_LANAI_LANAITARGETTRANSFORMINFO_H 17 #define LLVM_LIB_TARGET_LANAI_LANAITARGETTRANSFORMINFO_H 18 19 #include "Lanai.h" 20 #include "LanaiSubtarget.h" 21 #include "LanaiTargetMachine.h" 22 #include "llvm/Analysis/TargetTransformInfo.h" 23 #include "llvm/CodeGen/BasicTTIImpl.h" 24 #include "llvm/CodeGen/TargetLowering.h" 25 #include "llvm/Support/MathExtras.h" 26 27 namespace llvm { 28 class LanaiTTIImpl : public BasicTTIImplBase<LanaiTTIImpl> { 29 typedef BasicTTIImplBase<LanaiTTIImpl> BaseT; 30 typedef TargetTransformInfo TTI; 31 friend BaseT; 32 33 const LanaiSubtarget *ST; 34 const LanaiTargetLowering *TLI; 35 36 const LanaiSubtarget *getST() const { return ST; } 37 const LanaiTargetLowering *getTLI() const { return TLI; } 38 39 public: 40 explicit LanaiTTIImpl(const LanaiTargetMachine *TM, const Function &F) 41 : BaseT(TM, F.getParent()->getDataLayout()), ST(TM->getSubtargetImpl(F)), 42 TLI(ST->getTargetLowering()) {} 43 44 bool shouldBuildLookupTables() const { return false; } 45 46 TargetTransformInfo::PopcntSupportKind getPopcntSupport(unsigned TyWidth) { 47 if (TyWidth == 32) 48 return TTI::PSK_FastHardware; 49 return TTI::PSK_Software; 50 } 51 52 InstructionCost getIntImmCost(const APInt &Imm, Type *Ty, 53 TTI::TargetCostKind CostKind) { 54 assert(Ty->isIntegerTy()); 55 unsigned BitSize = Ty->getPrimitiveSizeInBits(); 56 // There is no cost model for constants with a bit size of 0. Return 57 // TCC_Free here, so that constant hoisting will ignore this constant. 58 if (BitSize == 0) 59 return TTI::TCC_Free; 60 // No cost model for operations on integers larger than 64 bit implemented 61 // yet. 62 if (BitSize > 64) 63 return TTI::TCC_Free; 64 65 if (Imm == 0) 66 return TTI::TCC_Free; 67 if (isInt<16>(Imm.getSExtValue())) 68 return TTI::TCC_Basic; 69 if (isInt<21>(Imm.getZExtValue())) 70 return TTI::TCC_Basic; 71 if (isInt<32>(Imm.getSExtValue())) { 72 if ((Imm.getSExtValue() & 0xFFFF) == 0) 73 return TTI::TCC_Basic; 74 return 2 * TTI::TCC_Basic; 75 } 76 77 return 4 * TTI::TCC_Basic; 78 } 79 80 InstructionCost getIntImmCostInst(unsigned Opc, unsigned Idx, 81 const APInt &Imm, Type *Ty, 82 TTI::TargetCostKind CostKind, 83 Instruction *Inst = nullptr) { 84 return getIntImmCost(Imm, Ty, CostKind); 85 } 86 87 InstructionCost getIntImmCostIntrin(Intrinsic::ID IID, unsigned Idx, 88 const APInt &Imm, Type *Ty, 89 TTI::TargetCostKind CostKind) { 90 return getIntImmCost(Imm, Ty, CostKind); 91 } 92 93 InstructionCost getArithmeticInstrCost( 94 unsigned Opcode, Type *Ty, TTI::TargetCostKind CostKind, 95 TTI::OperandValueInfo Op1Info = {TTI::OK_AnyValue, TTI::OP_None}, 96 TTI::OperandValueInfo Op2Info = {TTI::OK_AnyValue, TTI::OP_None}, 97 ArrayRef<const Value *> Args = ArrayRef<const Value *>(), 98 const Instruction *CxtI = nullptr) { 99 int ISD = TLI->InstructionOpcodeToISD(Opcode); 100 101 switch (ISD) { 102 default: 103 return BaseT::getArithmeticInstrCost(Opcode, Ty, CostKind, Op1Info, 104 Op2Info); 105 case ISD::MUL: 106 case ISD::SDIV: 107 case ISD::UDIV: 108 case ISD::UREM: 109 // This increases the cost associated with multiplication and division 110 // to 64 times what the baseline arithmetic cost is. The arithmetic 111 // instruction cost was arbitrarily chosen to reduce the desirability 112 // of emitting arithmetic instructions that are emulated in software. 113 // TODO: Investigate the performance impact given specialized lowerings. 114 return 64 * BaseT::getArithmeticInstrCost(Opcode, Ty, CostKind, Op1Info, 115 Op2Info); 116 } 117 } 118 }; 119 120 } // end namespace llvm 121 122 #endif // LLVM_LIB_TARGET_LANAI_LANAITARGETTRANSFORMINFO_H 123