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.getParent()->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(unsigned Opcode, Type *ValTy, Type *CondTy,
48                                      CmpInst::Predicate VecPred,
49                                      TTI::TargetCostKind CostKind,
50                                      const llvm::Instruction *I = nullptr) {
51     if (Opcode == Instruction::Select)
52       return SCEVCheapExpansionBudget.getValue();
53 
54     return BaseT::getCmpSelInstrCost(Opcode, ValTy, CondTy, VecPred, CostKind,
55                                      I);
56   }
57 
58   InstructionCost getArithmeticInstrCost(
59       unsigned Opcode, Type *Ty, TTI::TargetCostKind CostKind,
60       TTI::OperandValueInfo Op1Info = {TTI::OK_AnyValue, TTI::OP_None},
61       TTI::OperandValueInfo Op2Info = {TTI::OK_AnyValue, TTI::OP_None},
62     ArrayRef<const Value *> Args = ArrayRef<const Value *>(),
63     const Instruction *CxtI = nullptr) {
64       int ISD = TLI->InstructionOpcodeToISD(Opcode);
65       if (ISD == ISD::ADD && CostKind == TTI::TCK_RecipThroughput)
66         return SCEVCheapExpansionBudget.getValue() + 1;
67 
68       return BaseT::getArithmeticInstrCost(Opcode, Ty, CostKind, Op1Info,
69                                            Op2Info);
70   }
71 
72   TTI::MemCmpExpansionOptions enableMemCmpExpansion(bool OptSize,
73                                                     bool IsZeroCmp) const {
74     TTI::MemCmpExpansionOptions Options;
75     Options.LoadSizes = {8, 4, 2, 1};
76     Options.MaxNumLoads = TLI->getMaxExpandSizeMemcmp(OptSize);
77     return Options;
78   }
79 
80 };
81 
82 } // end namespace llvm
83 
84 #endif // LLVM_LIB_TARGET_BPF_BPFTARGETTRANSFORMINFO_H
85