lib/Target/Lanai/LanaiTargetTransformInfo.h

   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   int getIntImmCost(const APInt &Imm, Type *Ty) {
  53     assert(Ty->isIntegerTy());
  54     if (Imm == 0)
  55       return TTI::TCC_Free;
  56     if (isInt<16>(Imm.getSExtValue()))
  57       return TTI::TCC_Basic;
  58     if (isInt<21>(Imm.getZExtValue()))
  59       return TTI::TCC_Basic;
  60     if (isInt<32>(Imm.getSExtValue())) {
  61       if ((Imm.getSExtValue() & 0xFFFF) == 0)
  62         return TTI::TCC_Basic;
  63       return 2 * TTI::TCC_Basic;
  64     }
  65
  66     return 4 * TTI::TCC_Basic;
  67   }
  68
  69   int getIntImmCost(unsigned Opc, unsigned Idx, const APInt &Imm, Type *Ty) {
  70     return getIntImmCost(Imm, Ty);
  71   }
  72
  73   int getIntImmCost(Intrinsic::ID IID, unsigned Idx, const APInt &Imm,
  74                     Type *Ty) {
  75     return getIntImmCost(Imm, Ty);
  76   }
  77
  78   unsigned getArithmeticInstrCost(
  79       unsigned Opcode, Type *Ty,
  80       TTI::OperandValueKind Opd1Info = TTI::OK_AnyValue,
  81       TTI::OperandValueKind Opd2Info = TTI::OK_AnyValue,
  82       TTI::OperandValueProperties Opd1PropInfo = TTI::OP_None,
  83       TTI::OperandValueProperties Opd2PropInfo = TTI::OP_None,
  84       ArrayRef<const Value *> Args = ArrayRef<const Value *>()) {
  85     int ISD = TLI->InstructionOpcodeToISD(Opcode);
  86
  87     switch (ISD) {
  88     default:
  89       return BaseT::getArithmeticInstrCost(Opcode, Ty, Opd1Info, Opd2Info,
  90                                            Opd1PropInfo, Opd2PropInfo);
  91     case ISD::MUL:
  92     case ISD::SDIV:
  93     case ISD::UDIV:
  94     case ISD::UREM:
  95       // This increases the cost associated with multiplication and division
  96       // to 64 times what the baseline arithmetic cost is. The arithmetic
  97       // instruction cost was arbitrarily chosen to reduce the desirability
  98       // of emitting arithmetic instructions that are emulated in software.
  99       // TODO: Investigate the performance impact given specialized lowerings.
 100       return 64 * BaseT::getArithmeticInstrCost(Opcode, Ty, Opd1Info, Opd2Info,
 101                                                 Opd1PropInfo, Opd2PropInfo);
 102     }
 103   }
 104 };
 105
 106 } // end namespace llvm
 107
 108 #endif // LLVM_LIB_TARGET_LANAI_LANAITARGETTRANSFORMINFO_H