1 //===-- LanaiTargetTransformInfo.h - Lanai specific TTI ---------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file a TargetTransformInfo::Concept conforming object specific to the
11 // Lanai target machine. It uses the target's detailed information to
12 // provide more precise answers to certain TTI queries, while letting the
13 // target independent and default TTI implementations handle the rest.
14 //
15 //===----------------------------------------------------------------------===//
16 
17 #ifndef LLVM_LIB_TARGET_LANAI_LANAITARGETTRANSFORMINFO_H
18 #define LLVM_LIB_TARGET_LANAI_LANAITARGETTRANSFORMINFO_H
19 
20 #include "Lanai.h"
21 #include "LanaiSubtarget.h"
22 #include "LanaiTargetMachine.h"
23 #include "llvm/Analysis/TargetTransformInfo.h"
24 #include "llvm/CodeGen/BasicTTIImpl.h"
25 #include "llvm/CodeGen/TargetLowering.h"
26 #include "llvm/Support/MathExtras.h"
27 
28 namespace llvm {
29 class LanaiTTIImpl : public BasicTTIImplBase<LanaiTTIImpl> {
30   typedef BasicTTIImplBase<LanaiTTIImpl> BaseT;
31   typedef TargetTransformInfo TTI;
32   friend BaseT;
33 
34   const LanaiSubtarget *ST;
35   const LanaiTargetLowering *TLI;
36 
getST()37   const LanaiSubtarget *getST() const { return ST; }
getTLI()38   const LanaiTargetLowering *getTLI() const { return TLI; }
39 
40 public:
LanaiTTIImpl(const LanaiTargetMachine * TM,const Function & F)41   explicit LanaiTTIImpl(const LanaiTargetMachine *TM, const Function &F)
42       : BaseT(TM, F.getParent()->getDataLayout()), ST(TM->getSubtargetImpl(F)),
43         TLI(ST->getTargetLowering()) {}
44 
shouldBuildLookupTables()45   bool shouldBuildLookupTables() const { return false; }
46 
getPopcntSupport(unsigned TyWidth)47   TargetTransformInfo::PopcntSupportKind getPopcntSupport(unsigned TyWidth) {
48     if (TyWidth == 32)
49       return TTI::PSK_FastHardware;
50     return TTI::PSK_Software;
51   }
52 
getIntImmCost(const APInt & Imm,Type * Ty)53   int getIntImmCost(const APInt &Imm, Type *Ty) {
54     assert(Ty->isIntegerTy());
55     if (Imm == 0)
56       return TTI::TCC_Free;
57     if (isInt<16>(Imm.getSExtValue()))
58       return TTI::TCC_Basic;
59     if (isInt<21>(Imm.getZExtValue()))
60       return TTI::TCC_Basic;
61     if (isInt<32>(Imm.getSExtValue())) {
62       if ((Imm.getSExtValue() & 0xFFFF) == 0)
63         return TTI::TCC_Basic;
64       return 2 * TTI::TCC_Basic;
65     }
66 
67     return 4 * TTI::TCC_Basic;
68   }
69 
getIntImmCost(unsigned Opc,unsigned Idx,const APInt & Imm,Type * Ty)70   int getIntImmCost(unsigned Opc, unsigned Idx, const APInt &Imm, Type *Ty) {
71     return getIntImmCost(Imm, Ty);
72   }
73 
getIntImmCost(Intrinsic::ID IID,unsigned Idx,const APInt & Imm,Type * Ty)74   int getIntImmCost(Intrinsic::ID IID, unsigned Idx, const APInt &Imm,
75                     Type *Ty) {
76     return getIntImmCost(Imm, Ty);
77   }
78 
79   unsigned getArithmeticInstrCost(
80       unsigned Opcode, Type *Ty,
81       TTI::OperandValueKind Opd1Info = TTI::OK_AnyValue,
82       TTI::OperandValueKind Opd2Info = TTI::OK_AnyValue,
83       TTI::OperandValueProperties Opd1PropInfo = TTI::OP_None,
84       TTI::OperandValueProperties Opd2PropInfo = TTI::OP_None,
85       ArrayRef<const Value *> Args = ArrayRef<const Value *>()) {
86     int ISD = TLI->InstructionOpcodeToISD(Opcode);
87 
88     switch (ISD) {
89     default:
90       return BaseT::getArithmeticInstrCost(Opcode, Ty, Opd1Info, Opd2Info,
91                                            Opd1PropInfo, Opd2PropInfo);
92     case ISD::MUL:
93     case ISD::SDIV:
94     case ISD::UDIV:
95     case ISD::UREM:
96       // This increases the cost associated with multiplication and division
97       // to 64 times what the baseline arithmetic cost is. The arithmetic
98       // instruction cost was arbitrarily chosen to reduce the desirability
99       // of emitting arithmetic instructions that are emulated in software.
100       // TODO: Investigate the performance impact given specialized lowerings.
101       return 64 * BaseT::getArithmeticInstrCost(Opcode, Ty, Opd1Info, Opd2Info,
102                                                 Opd1PropInfo, Opd2PropInfo);
103     }
104   }
105 };
106 
107 } // end namespace llvm
108 
109 #endif // LLVM_LIB_TARGET_LANAI_LANAITARGETTRANSFORMINFO_H
110