xref: /llvm-project/llvm/lib/Target/BPF/BPFTargetTransformInfo.h (revision d2885743630fcb35fdf64d21bd4bec62a5cb4d37)
1 //===------ BPFTargetTransformInfo.h - BPF 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 uses the target's specific information to
10 // provide more precise answers to certain TTI queries, while letting the
11 // target independent and default TTI implementations handle the rest.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #ifndef LLVM_LIB_TARGET_BPF_BPFTARGETTRANSFORMINFO_H
16 #define LLVM_LIB_TARGET_BPF_BPFTARGETTRANSFORMINFO_H
17 
18 #include "BPFTargetMachine.h"
19 #include "llvm/Analysis/TargetTransformInfo.h"
20 #include "llvm/CodeGen/BasicTTIImpl.h"
21 #include "llvm/Transforms/Utils/ScalarEvolutionExpander.h"
22 
23 namespace llvm {
24 class BPFTTIImpl : public BasicTTIImplBase<BPFTTIImpl> {
25   typedef BasicTTIImplBase<BPFTTIImpl> BaseT;
26   typedef TargetTransformInfo TTI;
27   friend BaseT;
28 
29   const BPFSubtarget *ST;
30   const BPFTargetLowering *TLI;
31 
32   const BPFSubtarget *getST() const { return ST; }
33   const BPFTargetLowering *getTLI() const { return TLI; }
34 
35 public:
36   explicit BPFTTIImpl(const BPFTargetMachine *TM, const Function &F)
37       : BaseT(TM, F.getDataLayout()), ST(TM->getSubtargetImpl(F)),
38         TLI(ST->getTargetLowering()) {}
39 
40   int getIntImmCost(const APInt &Imm, Type *Ty, TTI::TargetCostKind CostKind) {
41     if (Imm.getBitWidth() <= 64 && isInt<32>(Imm.getSExtValue()))
42       return TTI::TCC_Free;
43 
44     return TTI::TCC_Basic;
45   }
46 
47   InstructionCost getCmpSelInstrCost(
48       unsigned Opcode, Type *ValTy, Type *CondTy, CmpInst::Predicate VecPred,
49       TTI::TargetCostKind CostKind,
50       TTI::OperandValueInfo Op1Info = {TTI::OK_AnyValue, TTI::OP_None},
51       TTI::OperandValueInfo Op2Info = {TTI::OK_AnyValue, TTI::OP_None},
52       const llvm::Instruction *I = nullptr) {
53     if (Opcode == Instruction::Select)
54       return SCEVCheapExpansionBudget.getValue();
55 
56     return BaseT::getCmpSelInstrCost(Opcode, ValTy, CondTy, VecPred, CostKind,
57                                      Op1Info, Op2Info, I);
58   }
59 
60   InstructionCost getArithmeticInstrCost(
61       unsigned Opcode, Type *Ty, TTI::TargetCostKind CostKind,
62       TTI::OperandValueInfo Op1Info = {TTI::OK_AnyValue, TTI::OP_None},
63       TTI::OperandValueInfo Op2Info = {TTI::OK_AnyValue, TTI::OP_None},
64       ArrayRef<const Value *> Args = {}, const Instruction *CxtI = nullptr) {
65     int ISD = TLI->InstructionOpcodeToISD(Opcode);
66     if (ISD == ISD::ADD && CostKind == TTI::TCK_RecipThroughput)
67       return SCEVCheapExpansionBudget.getValue() + 1;
68 
69     return BaseT::getArithmeticInstrCost(Opcode, Ty, CostKind, Op1Info,
70                                          Op2Info);
71   }
72 
73   TTI::MemCmpExpansionOptions enableMemCmpExpansion(bool OptSize,
74                                                     bool IsZeroCmp) const {
75     TTI::MemCmpExpansionOptions Options;
76     Options.LoadSizes = {8, 4, 2, 1};
77     Options.MaxNumLoads = TLI->getMaxExpandSizeMemcmp(OptSize);
78     return Options;
79   }
80 
81   unsigned getMaxNumArgs() const {
82     return 5;
83   }
84 
85 };
86 
87 } // end namespace llvm
88 
89 #endif // LLVM_LIB_TARGET_BPF_BPFTARGETTRANSFORMINFO_H
90