1 //===-- X86TargetTransformInfo.h - X86 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 /// \file
9 /// This file a TargetTransformInfo::Concept conforming object specific to the
10 /// X86 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_X86_X86TARGETTRANSFORMINFO_H
17 #define LLVM_LIB_TARGET_X86_X86TARGETTRANSFORMINFO_H
18 
19 #include "X86TargetMachine.h"
20 #include "llvm/Analysis/TargetTransformInfo.h"
21 #include "llvm/CodeGen/BasicTTIImpl.h"
22 
23 namespace llvm {
24 
25 class InstCombiner;
26 
27 class X86TTIImpl : public BasicTTIImplBase<X86TTIImpl> {
28   typedef BasicTTIImplBase<X86TTIImpl> BaseT;
29   typedef TargetTransformInfo TTI;
30   friend BaseT;
31 
32   const X86Subtarget *ST;
33   const X86TargetLowering *TLI;
34 
35   const X86Subtarget *getST() const { return ST; }
36   const X86TargetLowering *getTLI() const { return TLI; }
37 
38   const FeatureBitset InlineFeatureIgnoreList = {
39       // This indicates the CPU is 64 bit capable not that we are in 64-bit
40       // mode.
41       X86::Feature64Bit,
42 
43       // These features don't have any intrinsics or ABI effect.
44       X86::FeatureNOPL,
45       X86::FeatureCMPXCHG16B,
46       X86::FeatureLAHFSAHF,
47 
48       // Codegen control options.
49       X86::FeatureFast11ByteNOP,
50       X86::FeatureFast15ByteNOP,
51       X86::FeatureFastBEXTR,
52       X86::FeatureFastHorizontalOps,
53       X86::FeatureFastLZCNT,
54       X86::FeatureFastScalarFSQRT,
55       X86::FeatureFastSHLDRotate,
56       X86::FeatureFastScalarShiftMasks,
57       X86::FeatureFastVectorShiftMasks,
58       X86::FeatureFastVariableCrossLaneShuffle,
59       X86::FeatureFastVariablePerLaneShuffle,
60       X86::FeatureFastVectorFSQRT,
61       X86::FeatureLEAForSP,
62       X86::FeatureLEAUsesAG,
63       X86::FeatureLZCNTFalseDeps,
64       X86::FeatureBranchFusion,
65       X86::FeatureMacroFusion,
66       X86::FeaturePadShortFunctions,
67       X86::FeaturePOPCNTFalseDeps,
68       X86::FeatureSSEUnalignedMem,
69       X86::FeatureSlow3OpsLEA,
70       X86::FeatureSlowDivide32,
71       X86::FeatureSlowDivide64,
72       X86::FeatureSlowIncDec,
73       X86::FeatureSlowLEA,
74       X86::FeatureSlowPMADDWD,
75       X86::FeatureSlowPMULLD,
76       X86::FeatureSlowSHLD,
77       X86::FeatureSlowTwoMemOps,
78       X86::FeatureSlowUAMem16,
79       X86::FeaturePreferMaskRegisters,
80       X86::FeatureInsertVZEROUPPER,
81       X86::FeatureUseGLMDivSqrtCosts,
82 
83       // Perf-tuning flags.
84       X86::FeatureHasFastGather,
85       X86::FeatureSlowUAMem32,
86 
87       // Based on whether user set the -mprefer-vector-width command line.
88       X86::FeaturePrefer128Bit,
89       X86::FeaturePrefer256Bit,
90 
91       // CPU name enums. These just follow CPU string.
92       X86::ProcIntelAtom,
93       X86::ProcIntelSLM,
94   };
95 
96 public:
97   explicit X86TTIImpl(const X86TargetMachine *TM, const Function &F)
98       : BaseT(TM, F.getParent()->getDataLayout()), ST(TM->getSubtargetImpl(F)),
99         TLI(ST->getTargetLowering()) {}
100 
101   /// \name Scalar TTI Implementations
102   /// @{
103   TTI::PopcntSupportKind getPopcntSupport(unsigned TyWidth);
104 
105   /// @}
106 
107   /// \name Cache TTI Implementation
108   /// @{
109   llvm::Optional<unsigned> getCacheSize(
110     TargetTransformInfo::CacheLevel Level) const override;
111   llvm::Optional<unsigned> getCacheAssociativity(
112     TargetTransformInfo::CacheLevel Level) const override;
113   /// @}
114 
115   /// \name Vector TTI Implementations
116   /// @{
117 
118   unsigned getNumberOfRegisters(unsigned ClassID) const;
119   TypeSize getRegisterBitWidth(TargetTransformInfo::RegisterKind K) const;
120   unsigned getLoadStoreVecRegBitWidth(unsigned AS) const;
121   unsigned getMaxInterleaveFactor(unsigned VF);
122   InstructionCost getArithmeticInstrCost(
123       unsigned Opcode, Type *Ty,
124       TTI::TargetCostKind CostKind = TTI::TCK_RecipThroughput,
125       TTI::OperandValueKind Opd1Info = TTI::OK_AnyValue,
126       TTI::OperandValueKind Opd2Info = TTI::OK_AnyValue,
127       TTI::OperandValueProperties Opd1PropInfo = TTI::OP_None,
128       TTI::OperandValueProperties Opd2PropInfo = TTI::OP_None,
129       ArrayRef<const Value *> Args = ArrayRef<const Value *>(),
130       const Instruction *CxtI = nullptr);
131   InstructionCost getShuffleCost(TTI::ShuffleKind Kind, VectorType *Tp,
132                                  ArrayRef<int> Mask, int Index,
133                                  VectorType *SubTp);
134   InstructionCost getCastInstrCost(unsigned Opcode, Type *Dst, Type *Src,
135                                    TTI::CastContextHint CCH,
136                                    TTI::TargetCostKind CostKind,
137                                    const Instruction *I = nullptr);
138   InstructionCost getCmpSelInstrCost(unsigned Opcode, Type *ValTy, Type *CondTy,
139                                      CmpInst::Predicate VecPred,
140                                      TTI::TargetCostKind CostKind,
141                                      const Instruction *I = nullptr);
142   InstructionCost getVectorInstrCost(unsigned Opcode, Type *Val,
143                                      unsigned Index);
144   InstructionCost getScalarizationOverhead(VectorType *Ty,
145                                            const APInt &DemandedElts,
146                                            bool Insert, bool Extract);
147   InstructionCost getMemoryOpCost(unsigned Opcode, Type *Src,
148                                   MaybeAlign Alignment, unsigned AddressSpace,
149                                   TTI::TargetCostKind CostKind,
150                                   const Instruction *I = nullptr);
151   InstructionCost
152   getMaskedMemoryOpCost(unsigned Opcode, Type *Src, Align Alignment,
153                         unsigned AddressSpace,
154                         TTI::TargetCostKind CostKind = TTI::TCK_SizeAndLatency);
155   InstructionCost getGatherScatterOpCost(unsigned Opcode, Type *DataTy,
156                                          const Value *Ptr, bool VariableMask,
157                                          Align Alignment,
158                                          TTI::TargetCostKind CostKind,
159                                          const Instruction *I);
160   InstructionCost getAddressComputationCost(Type *PtrTy, ScalarEvolution *SE,
161                                             const SCEV *Ptr);
162 
163   Optional<Instruction *> instCombineIntrinsic(InstCombiner &IC,
164                                                IntrinsicInst &II) const;
165   Optional<Value *>
166   simplifyDemandedUseBitsIntrinsic(InstCombiner &IC, IntrinsicInst &II,
167                                    APInt DemandedMask, KnownBits &Known,
168                                    bool &KnownBitsComputed) const;
169   Optional<Value *> simplifyDemandedVectorEltsIntrinsic(
170       InstCombiner &IC, IntrinsicInst &II, APInt DemandedElts, APInt &UndefElts,
171       APInt &UndefElts2, APInt &UndefElts3,
172       std::function<void(Instruction *, unsigned, APInt, APInt &)>
173           SimplifyAndSetOp) const;
174 
175   unsigned getAtomicMemIntrinsicMaxElementSize() const;
176 
177   InstructionCost
178   getTypeBasedIntrinsicInstrCost(const IntrinsicCostAttributes &ICA,
179                                  TTI::TargetCostKind CostKind);
180   InstructionCost getIntrinsicInstrCost(const IntrinsicCostAttributes &ICA,
181                                         TTI::TargetCostKind CostKind);
182 
183   InstructionCost getArithmeticReductionCost(
184       unsigned Opcode, VectorType *Ty, Optional<FastMathFlags> FMF,
185       TTI::TargetCostKind CostKind = TTI::TCK_SizeAndLatency);
186 
187   InstructionCost getMinMaxCost(Type *Ty, Type *CondTy, bool IsUnsigned);
188 
189   InstructionCost getMinMaxReductionCost(VectorType *Ty, VectorType *CondTy,
190                                          bool IsUnsigned,
191                                          TTI::TargetCostKind CostKind);
192 
193   InstructionCost getInterleavedMemoryOpCost(
194       unsigned Opcode, Type *VecTy, unsigned Factor, ArrayRef<unsigned> Indices,
195       Align Alignment, unsigned AddressSpace,
196       TTI::TargetCostKind CostKind = TTI::TCK_SizeAndLatency,
197       bool UseMaskForCond = false, bool UseMaskForGaps = false);
198   InstructionCost getInterleavedMemoryOpCostAVX512(
199       unsigned Opcode, FixedVectorType *VecTy, unsigned Factor,
200       ArrayRef<unsigned> Indices, Align Alignment, unsigned AddressSpace,
201       TTI::TargetCostKind CostKind = TTI::TCK_SizeAndLatency,
202       bool UseMaskForCond = false, bool UseMaskForGaps = false);
203   InstructionCost getInterleavedMemoryOpCostAVX2(
204       unsigned Opcode, FixedVectorType *VecTy, unsigned Factor,
205       ArrayRef<unsigned> Indices, Align Alignment, unsigned AddressSpace,
206       TTI::TargetCostKind CostKind = TTI::TCK_SizeAndLatency,
207       bool UseMaskForCond = false, bool UseMaskForGaps = false);
208 
209   InstructionCost getIntImmCost(int64_t);
210 
211   InstructionCost getIntImmCost(const APInt &Imm, Type *Ty,
212                                 TTI::TargetCostKind CostKind);
213 
214   InstructionCost getCFInstrCost(unsigned Opcode, TTI::TargetCostKind CostKind,
215                                  const Instruction *I = nullptr);
216 
217   InstructionCost getIntImmCostInst(unsigned Opcode, unsigned Idx,
218                                     const APInt &Imm, Type *Ty,
219                                     TTI::TargetCostKind CostKind,
220                                     Instruction *Inst = nullptr);
221   InstructionCost getIntImmCostIntrin(Intrinsic::ID IID, unsigned Idx,
222                                       const APInt &Imm, Type *Ty,
223                                       TTI::TargetCostKind CostKind);
224   bool isLSRCostLess(TargetTransformInfo::LSRCost &C1,
225                      TargetTransformInfo::LSRCost &C2);
226   bool canMacroFuseCmp();
227   bool isLegalMaskedLoad(Type *DataType, Align Alignment);
228   bool isLegalMaskedStore(Type *DataType, Align Alignment);
229   bool isLegalNTLoad(Type *DataType, Align Alignment);
230   bool isLegalNTStore(Type *DataType, Align Alignment);
231   bool isLegalMaskedGather(Type *DataType, Align Alignment);
232   bool isLegalMaskedScatter(Type *DataType, Align Alignment);
233   bool isLegalMaskedExpandLoad(Type *DataType);
234   bool isLegalMaskedCompressStore(Type *DataType);
235   bool hasDivRemOp(Type *DataType, bool IsSigned);
236   bool isFCmpOrdCheaperThanFCmpZero(Type *Ty);
237   bool areInlineCompatible(const Function *Caller,
238                            const Function *Callee) const;
239   bool areFunctionArgsABICompatible(const Function *Caller,
240                                     const Function *Callee,
241                                     SmallPtrSetImpl<Argument *> &Args) const;
242   TTI::MemCmpExpansionOptions enableMemCmpExpansion(bool OptSize,
243                                                     bool IsZeroCmp) const;
244   bool enableInterleavedAccessVectorization();
245 
246 private:
247   InstructionCost getGSScalarCost(unsigned Opcode, Type *DataTy,
248                                   bool VariableMask, Align Alignment,
249                                   unsigned AddressSpace);
250   InstructionCost getGSVectorCost(unsigned Opcode, Type *DataTy,
251                                   const Value *Ptr, Align Alignment,
252                                   unsigned AddressSpace);
253 
254   int getGatherOverhead() const;
255   int getScatterOverhead() const;
256 
257   /// @}
258 };
259 
260 } // end namespace llvm
261 
262 #endif
263