LLVM 19.0.0git
TargetFolder.h
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1//====- TargetFolder.h - Constant folding helper ---------------*- 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 defines the TargetFolder class, a helper for IRBuilder.
10// It provides IRBuilder with a set of methods for creating constants with
11// target dependent folding, in addition to the same target-independent
12// folding that the ConstantFolder class provides. For general constant
13// creation and folding, use ConstantExpr and the routines in
14// llvm/Analysis/ConstantFolding.h.
15//
16//===----------------------------------------------------------------------===//
17
18#ifndef LLVM_ANALYSIS_TARGETFOLDER_H
19#define LLVM_ANALYSIS_TARGETFOLDER_H
20
21#include "llvm/ADT/ArrayRef.h"
23#include "llvm/IR/Constants.h"
25#include "llvm/IR/Operator.h"
26
27namespace llvm {
28
29class Constant;
30class DataLayout;
31class Type;
32
33/// TargetFolder - Create constants with target dependent folding.
34class TargetFolder final : public IRBuilderFolder {
35 const DataLayout &DL;
36
37 /// Fold - Fold the constant using target specific information.
38 Constant *Fold(Constant *C) const {
39 return ConstantFoldConstant(C, DL);
40 }
41
42 virtual void anchor();
43
44public:
45 explicit TargetFolder(const DataLayout &DL) : DL(DL) {}
46
47 //===--------------------------------------------------------------------===//
48 // Value-based folders.
49 //
50 // Return an existing value or a constant if the operation can be simplified.
51 // Otherwise return nullptr.
52 //===--------------------------------------------------------------------===//
53
55 Value *RHS) const override {
56 auto *LC = dyn_cast<Constant>(LHS);
57 auto *RC = dyn_cast<Constant>(RHS);
58 if (LC && RC) {
60 return Fold(ConstantExpr::get(Opc, LC, RC));
61 return ConstantFoldBinaryOpOperands(Opc, LC, RC, DL);
62 }
63 return nullptr;
64 }
65
67 bool IsExact) const override {
68 auto *LC = dyn_cast<Constant>(LHS);
69 auto *RC = dyn_cast<Constant>(RHS);
70 if (LC && RC) {
72 return Fold(ConstantExpr::get(
73 Opc, LC, RC, IsExact ? PossiblyExactOperator::IsExact : 0));
74 return ConstantFoldBinaryOpOperands(Opc, LC, RC, DL);
75 }
76 return nullptr;
77 }
78
80 bool HasNUW, bool HasNSW) const override {
81 auto *LC = dyn_cast<Constant>(LHS);
82 auto *RC = dyn_cast<Constant>(RHS);
83 if (LC && RC) {
85 unsigned Flags = 0;
86 if (HasNUW)
88 if (HasNSW)
90 return Fold(ConstantExpr::get(Opc, LC, RC, Flags));
91 }
92 return ConstantFoldBinaryOpOperands(Opc, LC, RC, DL);
93 }
94 return nullptr;
95 }
96
98 FastMathFlags FMF) const override {
99 return FoldBinOp(Opc, LHS, RHS);
100 }
101
103 auto *LC = dyn_cast<Constant>(LHS);
104 auto *RC = dyn_cast<Constant>(RHS);
105 if (LC && RC)
106 return ConstantFoldCompareInstOperands(P, LC, RC, DL);
107 return nullptr;
108 }
109
111 FastMathFlags FMF) const override {
112 if (Constant *C = dyn_cast<Constant>(V))
113 return ConstantFoldUnaryOpOperand(Opc, C, DL);
114 return nullptr;
115 }
116
118 GEPNoWrapFlags NW) const override {
120 return nullptr;
121
122 if (auto *PC = dyn_cast<Constant>(Ptr)) {
123 // Every index must be constant.
124 if (any_of(IdxList, [](Value *V) { return !isa<Constant>(V); }))
125 return nullptr;
126 return Fold(ConstantExpr::getGetElementPtr(Ty, PC, IdxList, NW));
127 }
128 return nullptr;
129 }
130
131 Value *FoldSelect(Value *C, Value *True, Value *False) const override {
132 auto *CC = dyn_cast<Constant>(C);
133 auto *TC = dyn_cast<Constant>(True);
134 auto *FC = dyn_cast<Constant>(False);
135 if (CC && TC && FC)
136 return ConstantFoldSelectInstruction(CC, TC, FC);
137
138 return nullptr;
139 }
140
142 ArrayRef<unsigned> IdxList) const override {
143 if (auto *CAgg = dyn_cast<Constant>(Agg))
144 return ConstantFoldExtractValueInstruction(CAgg, IdxList);
145 return nullptr;
146 };
147
149 ArrayRef<unsigned> IdxList) const override {
150 auto *CAgg = dyn_cast<Constant>(Agg);
151 auto *CVal = dyn_cast<Constant>(Val);
152 if (CAgg && CVal)
153 return ConstantFoldInsertValueInstruction(CAgg, CVal, IdxList);
154 return nullptr;
155 }
156
157 Value *FoldExtractElement(Value *Vec, Value *Idx) const override {
158 auto *CVec = dyn_cast<Constant>(Vec);
159 auto *CIdx = dyn_cast<Constant>(Idx);
160 if (CVec && CIdx)
161 return Fold(ConstantExpr::getExtractElement(CVec, CIdx));
162 return nullptr;
163 }
164
166 Value *Idx) const override {
167 auto *CVec = dyn_cast<Constant>(Vec);
168 auto *CNewElt = dyn_cast<Constant>(NewElt);
169 auto *CIdx = dyn_cast<Constant>(Idx);
170 if (CVec && CNewElt && CIdx)
171 return Fold(ConstantExpr::getInsertElement(CVec, CNewElt, CIdx));
172 return nullptr;
173 }
174
176 ArrayRef<int> Mask) const override {
177 auto *C1 = dyn_cast<Constant>(V1);
178 auto *C2 = dyn_cast<Constant>(V2);
179 if (C1 && C2)
180 return Fold(ConstantExpr::getShuffleVector(C1, C2, Mask));
181 return nullptr;
182 }
183
185 Type *DestTy) const override {
186 if (auto *C = dyn_cast<Constant>(V))
187 return ConstantFoldCastOperand(Op, C, DestTy, DL);
188 return nullptr;
189 }
190
192 Instruction *FMFSource) const override {
193 auto *C1 = dyn_cast<Constant>(LHS);
194 auto *C2 = dyn_cast<Constant>(RHS);
195 if (C1 && C2)
196 return ConstantFoldBinaryIntrinsic(ID, C1, C2, Ty, FMFSource);
197 return nullptr;
198 }
199
200 //===--------------------------------------------------------------------===//
201 // Cast/Conversion Operators
202 //===--------------------------------------------------------------------===//
203
204 Constant *CreatePointerCast(Constant *C, Type *DestTy) const override {
205 if (C->getType() == DestTy)
206 return C; // avoid calling Fold
207 return Fold(ConstantExpr::getPointerCast(C, DestTy));
208 }
209
211 Type *DestTy) const override {
212 if (C->getType() == DestTy)
213 return C; // avoid calling Fold
215 }
216};
217
218}
219
220#endif
MachineBasicBlock MachineBasicBlock::iterator DebugLoc DL
RelocType Type
Definition: COFFYAML.cpp:391
This file contains the declarations for the subclasses of Constant, which represent the different fla...
Returns the sub type a function will return at a given Idx Should correspond to the result type of an ExtractValue instruction executed with just that one unsigned Idx
#define P(N)
Value * RHS
Value * LHS
ArrayRef - Represent a constant reference to an array (0 or more elements consecutively in memory),...
Definition: ArrayRef.h:41
Predicate
This enumeration lists the possible predicates for CmpInst subclasses.
Definition: InstrTypes.h:757
static Constant * getExtractElement(Constant *Vec, Constant *Idx, Type *OnlyIfReducedTy=nullptr)
Definition: Constants.cpp:2516
static Constant * getPointerCast(Constant *C, Type *Ty)
Create a BitCast, AddrSpaceCast, or a PtrToInt cast constant expression.
Definition: Constants.cpp:2215
static Constant * getPointerBitCastOrAddrSpaceCast(Constant *C, Type *Ty)
Create a BitCast or AddrSpaceCast for a pointer type depending on the address space.
Definition: Constants.cpp:2230
static Constant * getInsertElement(Constant *Vec, Constant *Elt, Constant *Idx, Type *OnlyIfReducedTy=nullptr)
Definition: Constants.cpp:2538
static Constant * getShuffleVector(Constant *V1, Constant *V2, ArrayRef< int > Mask, Type *OnlyIfReducedTy=nullptr)
Definition: Constants.cpp:2561
static bool isSupportedGetElementPtr(const Type *SrcElemTy)
Whether creating a constant expression for this getelementptr type is supported.
Definition: Constants.h:1352
static Constant * get(unsigned Opcode, Constant *C1, Constant *C2, unsigned Flags=0, Type *OnlyIfReducedTy=nullptr)
get - Return a binary or shift operator constant expression, folding if possible.
Definition: Constants.cpp:2302
static bool isDesirableBinOp(unsigned Opcode)
Whether creating a constant expression for this binary operator is desirable.
Definition: Constants.cpp:2344
static Constant * getGetElementPtr(Type *Ty, Constant *C, ArrayRef< Constant * > IdxList, GEPNoWrapFlags NW=GEPNoWrapFlags::none(), std::optional< ConstantRange > InRange=std::nullopt, Type *OnlyIfReducedTy=nullptr)
Getelementptr form.
Definition: Constants.h:1240
This is an important base class in LLVM.
Definition: Constant.h:42
This class represents an Operation in the Expression.
A parsed version of the target data layout string in and methods for querying it.
Definition: DataLayout.h:110
Convenience struct for specifying and reasoning about fast-math flags.
Definition: FMF.h:20
Represents flags for the getelementptr instruction/expression.
IRBuilderFolder - Interface for constant folding in IRBuilder.
TargetFolder - Create constants with target dependent folding.
Definition: TargetFolder.h:34
Constant * CreatePointerCast(Constant *C, Type *DestTy) const override
Definition: TargetFolder.h:204
Value * FoldShuffleVector(Value *V1, Value *V2, ArrayRef< int > Mask) const override
Definition: TargetFolder.h:175
TargetFolder(const DataLayout &DL)
Definition: TargetFolder.h:45
Value * FoldInsertElement(Value *Vec, Value *NewElt, Value *Idx) const override
Definition: TargetFolder.h:165
Value * FoldSelect(Value *C, Value *True, Value *False) const override
Definition: TargetFolder.h:131
Value * FoldExtractValue(Value *Agg, ArrayRef< unsigned > IdxList) const override
Definition: TargetFolder.h:141
Value * FoldExactBinOp(Instruction::BinaryOps Opc, Value *LHS, Value *RHS, bool IsExact) const override
Definition: TargetFolder.h:66
Constant * CreatePointerBitCastOrAddrSpaceCast(Constant *C, Type *DestTy) const override
Definition: TargetFolder.h:210
Value * FoldUnOpFMF(Instruction::UnaryOps Opc, Value *V, FastMathFlags FMF) const override
Definition: TargetFolder.h:110
Value * FoldCmp(CmpInst::Predicate P, Value *LHS, Value *RHS) const override
Definition: TargetFolder.h:102
Value * FoldGEP(Type *Ty, Value *Ptr, ArrayRef< Value * > IdxList, GEPNoWrapFlags NW) const override
Definition: TargetFolder.h:117
Value * FoldNoWrapBinOp(Instruction::BinaryOps Opc, Value *LHS, Value *RHS, bool HasNUW, bool HasNSW) const override
Definition: TargetFolder.h:79
Value * FoldBinOp(Instruction::BinaryOps Opc, Value *LHS, Value *RHS) const override
Definition: TargetFolder.h:54
Value * FoldBinOpFMF(Instruction::BinaryOps Opc, Value *LHS, Value *RHS, FastMathFlags FMF) const override
Definition: TargetFolder.h:97
Value * FoldInsertValue(Value *Agg, Value *Val, ArrayRef< unsigned > IdxList) const override
Definition: TargetFolder.h:148
Value * FoldExtractElement(Value *Vec, Value *Idx) const override
Definition: TargetFolder.h:157
Value * FoldCast(Instruction::CastOps Op, Value *V, Type *DestTy) const override
Definition: TargetFolder.h:184
Value * FoldBinaryIntrinsic(Intrinsic::ID ID, Value *LHS, Value *RHS, Type *Ty, Instruction *FMFSource) const override
Definition: TargetFolder.h:191
The instances of the Type class are immutable: once they are created, they are never changed.
Definition: Type.h:45
LLVM Value Representation.
Definition: Value.h:74
@ C
The default llvm calling convention, compatible with C.
Definition: CallingConv.h:34
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18
Constant * ConstantFoldBinaryIntrinsic(Intrinsic::ID ID, Constant *LHS, Constant *RHS, Type *Ty, Instruction *FMFSource)
Constant * ConstantFoldSelectInstruction(Constant *Cond, Constant *V1, Constant *V2)
Attempt to constant fold a select instruction with the specified operands.
Constant * ConstantFoldCompareInstOperands(unsigned Predicate, Constant *LHS, Constant *RHS, const DataLayout &DL, const TargetLibraryInfo *TLI=nullptr, const Instruction *I=nullptr)
Attempt to constant fold a compare instruction (icmp/fcmp) with the specified operands.
Constant * ConstantFoldExtractValueInstruction(Constant *Agg, ArrayRef< unsigned > Idxs)
Attempt to constant fold an extractvalue instruction with the specified operands and indices.
Constant * ConstantFoldConstant(const Constant *C, const DataLayout &DL, const TargetLibraryInfo *TLI=nullptr)
ConstantFoldConstant - Fold the constant using the specified DataLayout.
bool any_of(R &&range, UnaryPredicate P)
Provide wrappers to std::any_of which take ranges instead of having to pass begin/end explicitly.
Definition: STLExtras.h:1729
Constant * ConstantFoldUnaryOpOperand(unsigned Opcode, Constant *Op, const DataLayout &DL)
Attempt to constant fold a unary operation with the specified operand.
Constant * ConstantFoldCastOperand(unsigned Opcode, Constant *C, Type *DestTy, const DataLayout &DL)
Attempt to constant fold a cast with the specified operand.
Constant * ConstantFoldBinaryOpOperands(unsigned Opcode, Constant *LHS, Constant *RHS, const DataLayout &DL)
Attempt to constant fold a binary operation with the specified operands.
Constant * ConstantFoldInsertValueInstruction(Constant *Agg, Constant *Val, ArrayRef< unsigned > Idxs)
ConstantFoldInsertValueInstruction - Attempt to constant fold an insertvalue instruction with the spe...