LLVM 19.0.0git
InstructionSimplify.h
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1//===-- InstructionSimplify.h - Fold instrs into simpler forms --*- 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 declares routines for folding instructions into simpler forms
10// that do not require creating new instructions. This does constant folding
11// ("add i32 1, 1" -> "2") but can also handle non-constant operands, either
12// returning a constant ("and i32 %x, 0" -> "0") or an already existing value
13// ("and i32 %x, %x" -> "%x"). If the simplification is also an instruction
14// then it dominates the original instruction.
15//
16// These routines implicitly resolve undef uses. The easiest way to be safe when
17// using these routines to obtain simplified values for existing instructions is
18// to always replace all uses of the instructions with the resulting simplified
19// values. This will prevent other code from seeing the same undef uses and
20// resolving them to different values.
21//
22// They require that all the IR that they encounter be valid and inserted into a
23// parent function.
24//
25// Additionally, these routines can't simplify to the instructions that are not
26// def-reachable, meaning we can't just scan the basic block for instructions
27// to simplify to.
28//
29//===----------------------------------------------------------------------===//
30
31#ifndef LLVM_ANALYSIS_INSTRUCTIONSIMPLIFY_H
32#define LLVM_ANALYSIS_INSTRUCTIONSIMPLIFY_H
33
35
36namespace llvm {
37
38template <typename T, typename... TArgs> class AnalysisManager;
39template <class T> class ArrayRef;
40class AssumptionCache;
41class BinaryOperator;
42class CallBase;
43class DataLayout;
44class DominatorTree;
45class Function;
46class Instruction;
47struct LoopStandardAnalysisResults;
48class Pass;
49template <class T, unsigned n> class SmallSetVector;
50class TargetLibraryInfo;
51class Type;
52class Value;
53
54// NOTE: the explicit multiple argument versions of these functions are
55// deprecated.
56// Please use the SimplifyQuery versions in new code.
57
58/// Given operands for an Add, fold the result or return null.
59Value *simplifyAddInst(Value *LHS, Value *RHS, bool IsNSW, bool IsNUW,
60 const SimplifyQuery &Q);
61
62/// Given operands for a Sub, fold the result or return null.
63Value *simplifySubInst(Value *LHS, Value *RHS, bool IsNSW, bool IsNUW,
64 const SimplifyQuery &Q);
65
66/// Given operands for a Mul, fold the result or return null.
67Value *simplifyMulInst(Value *LHS, Value *RHS, bool IsNSW, bool IsNUW,
68 const SimplifyQuery &Q);
69
70/// Given operands for an SDiv, fold the result or return null.
71Value *simplifySDivInst(Value *LHS, Value *RHS, bool IsExact,
72 const SimplifyQuery &Q);
73
74/// Given operands for a UDiv, fold the result or return null.
75Value *simplifyUDivInst(Value *LHS, Value *RHS, bool IsExact,
76 const SimplifyQuery &Q);
77
78/// Given operands for an SRem, fold the result or return null.
79Value *simplifySRemInst(Value *LHS, Value *RHS, const SimplifyQuery &Q);
80
81/// Given operands for a URem, fold the result or return null.
82Value *simplifyURemInst(Value *LHS, Value *RHS, const SimplifyQuery &Q);
83
84/// Given operand for an FNeg, fold the result or return null.
85Value *simplifyFNegInst(Value *Op, FastMathFlags FMF, const SimplifyQuery &Q);
86
87
88/// Given operands for an FAdd, fold the result or return null.
89Value *
90simplifyFAddInst(Value *LHS, Value *RHS, FastMathFlags FMF,
91 const SimplifyQuery &Q,
94
95/// Given operands for an FSub, fold the result or return null.
96Value *
97simplifyFSubInst(Value *LHS, Value *RHS, FastMathFlags FMF,
98 const SimplifyQuery &Q,
101
102/// Given operands for an FMul, fold the result or return null.
103Value *
104simplifyFMulInst(Value *LHS, Value *RHS, FastMathFlags FMF,
105 const SimplifyQuery &Q,
108
109/// Given operands for the multiplication of a FMA, fold the result or return
110/// null. In contrast to simplifyFMulInst, this function will not perform
111/// simplifications whose unrounded results differ when rounded to the argument
112/// type.
113Value *simplifyFMAFMul(Value *LHS, Value *RHS, FastMathFlags FMF,
114 const SimplifyQuery &Q,
117
118/// Given operands for an FDiv, fold the result or return null.
119Value *
120simplifyFDivInst(Value *LHS, Value *RHS, FastMathFlags FMF,
121 const SimplifyQuery &Q,
124
125/// Given operands for an FRem, fold the result or return null.
126Value *
127simplifyFRemInst(Value *LHS, Value *RHS, FastMathFlags FMF,
128 const SimplifyQuery &Q,
131
132/// Given operands for a Shl, fold the result or return null.
133Value *simplifyShlInst(Value *Op0, Value *Op1, bool IsNSW, bool IsNUW,
134 const SimplifyQuery &Q);
135
136/// Given operands for a LShr, fold the result or return null.
137Value *simplifyLShrInst(Value *Op0, Value *Op1, bool IsExact,
138 const SimplifyQuery &Q);
139
140/// Given operands for a AShr, fold the result or return nulll.
141Value *simplifyAShrInst(Value *Op0, Value *Op1, bool IsExact,
142 const SimplifyQuery &Q);
143
144/// Given operands for an And, fold the result or return null.
145Value *simplifyAndInst(Value *LHS, Value *RHS, const SimplifyQuery &Q);
146
147/// Given operands for an Or, fold the result or return null.
148Value *simplifyOrInst(Value *LHS, Value *RHS, const SimplifyQuery &Q);
149
150/// Given operands for an Xor, fold the result or return null.
151Value *simplifyXorInst(Value *LHS, Value *RHS, const SimplifyQuery &Q);
152
153/// Given operands for an ICmpInst, fold the result or return null.
154Value *simplifyICmpInst(unsigned Predicate, Value *LHS, Value *RHS,
155 const SimplifyQuery &Q);
156
157/// Given operands for an FCmpInst, fold the result or return null.
158Value *simplifyFCmpInst(unsigned Predicate, Value *LHS, Value *RHS,
159 FastMathFlags FMF, const SimplifyQuery &Q);
160
161/// Given operands for a SelectInst, fold the result or return null.
162Value *simplifySelectInst(Value *Cond, Value *TrueVal, Value *FalseVal,
163 const SimplifyQuery &Q);
164
165/// Given operands for a GetElementPtrInst, fold the result or return null.
166Value *simplifyGEPInst(Type *SrcTy, Value *Ptr, ArrayRef<Value *> Indices,
167 bool InBounds, const SimplifyQuery &Q);
168
169/// Given operands for an InsertValueInst, fold the result or return null.
170Value *simplifyInsertValueInst(Value *Agg, Value *Val, ArrayRef<unsigned> Idxs,
171 const SimplifyQuery &Q);
172
173/// Given operands for an InsertElement, fold the result or return null.
174Value *simplifyInsertElementInst(Value *Vec, Value *Elt, Value *Idx,
175 const SimplifyQuery &Q);
176
177/// Given operands for an ExtractValueInst, fold the result or return null.
178Value *simplifyExtractValueInst(Value *Agg, ArrayRef<unsigned> Idxs,
179 const SimplifyQuery &Q);
180
181/// Given operands for an ExtractElementInst, fold the result or return null.
182Value *simplifyExtractElementInst(Value *Vec, Value *Idx,
183 const SimplifyQuery &Q);
184
185/// Given operands for a CastInst, fold the result or return null.
186Value *simplifyCastInst(unsigned CastOpc, Value *Op, Type *Ty,
187 const SimplifyQuery &Q);
188
189/// Given operands for a ShuffleVectorInst, fold the result or return null.
190/// See class ShuffleVectorInst for a description of the mask representation.
191Value *simplifyShuffleVectorInst(Value *Op0, Value *Op1, ArrayRef<int> Mask,
192 Type *RetTy, const SimplifyQuery &Q);
193
194//=== Helper functions for higher up the class hierarchy.
195
196/// Given operands for a CmpInst, fold the result or return null.
197Value *simplifyCmpInst(unsigned Predicate, Value *LHS, Value *RHS,
198 const SimplifyQuery &Q);
199
200/// Given operand for a UnaryOperator, fold the result or return null.
201Value *simplifyUnOp(unsigned Opcode, Value *Op, const SimplifyQuery &Q);
202
203/// Given operand for a UnaryOperator, fold the result or return null.
204/// Try to use FastMathFlags when folding the result.
205Value *simplifyUnOp(unsigned Opcode, Value *Op, FastMathFlags FMF,
206 const SimplifyQuery &Q);
207
208/// Given operands for a BinaryOperator, fold the result or return null.
209Value *simplifyBinOp(unsigned Opcode, Value *LHS, Value *RHS,
210 const SimplifyQuery &Q);
211
212/// Given operands for a BinaryOperator, fold the result or return null.
213/// Try to use FastMathFlags when folding the result.
214Value *simplifyBinOp(unsigned Opcode, Value *LHS, Value *RHS, FastMathFlags FMF,
215 const SimplifyQuery &Q);
216
217/// Given a callsite, callee, and arguments, fold the result or return null.
218Value *simplifyCall(CallBase *Call, Value *Callee, ArrayRef<Value *> Args,
219 const SimplifyQuery &Q);
220
221/// Given a constrained FP intrinsic call, tries to compute its simplified
222/// version. Returns a simplified result or null.
223///
224/// This function provides an additional contract: it guarantees that if
225/// simplification succeeds that the intrinsic is side effect free. As a result,
226/// successful simplification can be used to delete the intrinsic not just
227/// replace its result.
228Value *simplifyConstrainedFPCall(CallBase *Call, const SimplifyQuery &Q);
229
230/// Given an operand for a Freeze, see if we can fold the result.
231/// If not, this returns null.
232Value *simplifyFreezeInst(Value *Op, const SimplifyQuery &Q);
233
234/// Given a load instruction and its pointer operand, fold the result or return
235/// null.
236Value *simplifyLoadInst(LoadInst *LI, Value *PtrOp, const SimplifyQuery &Q);
237
238/// See if we can compute a simplified version of this instruction. If not,
239/// return null.
240Value *simplifyInstruction(Instruction *I, const SimplifyQuery &Q);
241
242/// Like \p simplifyInstruction but the operands of \p I are replaced with
243/// \p NewOps. Returns a simplified value, or null if none was found.
244Value *
245simplifyInstructionWithOperands(Instruction *I, ArrayRef<Value *> NewOps,
246 const SimplifyQuery &Q);
247
248/// See if V simplifies when its operand Op is replaced with RepOp. If not,
249/// return null.
250/// AllowRefinement specifies whether the simplification can be a refinement
251/// (e.g. 0 instead of poison), or whether it needs to be strictly identical.
252/// Op and RepOp can be assumed to not be poison when determining refinement.
253///
254/// If DropFlags is passed, then the replacement result is only valid if
255/// poison-generating flags/metadata on those instructions are dropped. This
256/// is only useful in conjunction with AllowRefinement=false.
257Value *
258simplifyWithOpReplaced(Value *V, Value *Op, Value *RepOp,
259 const SimplifyQuery &Q, bool AllowRefinement,
260 SmallVectorImpl<Instruction *> *DropFlags = nullptr);
261
262/// Replace all uses of 'I' with 'SimpleV' and simplify the uses recursively.
263///
264/// This first performs a normal RAUW of I with SimpleV. It then recursively
265/// attempts to simplify those users updated by the operation. The 'I'
266/// instruction must not be equal to the simplified value 'SimpleV'.
267/// If UnsimplifiedUsers is provided, instructions that could not be simplified
268/// are added to it.
269///
270/// The function returns true if any simplifications were performed.
272 Instruction *I, Value *SimpleV, const TargetLibraryInfo *TLI = nullptr,
273 const DominatorTree *DT = nullptr, AssumptionCache *AC = nullptr,
274 SmallSetVector<Instruction *, 8> *UnsimplifiedUsers = nullptr);
275
276// These helper functions return a SimplifyQuery structure that contains as
277// many of the optional analysis we use as are currently valid. This is the
278// strongly preferred way of constructing SimplifyQuery in passes.
279const SimplifyQuery getBestSimplifyQuery(Pass &, Function &);
280template <class T, class... TArgs>
281const SimplifyQuery getBestSimplifyQuery(AnalysisManager<T, TArgs...> &,
282 Function &);
283const SimplifyQuery getBestSimplifyQuery(LoopStandardAnalysisResults &,
284 const DataLayout &);
285} // end namespace llvm
286
287#endif
aarch64 AArch64 CCMP Pass
RelocType Type
Definition: COFFYAML.cpp:391
return RetTy
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 I(x, y, z)
Definition: MD5.cpp:58
#define T
const SmallVectorImpl< MachineOperand > & Cond
Value * RHS
Value * LHS
ExceptionBehavior
Exception behavior used for floating point operations.
Definition: FPEnv.h:38
@ ebIgnore
This corresponds to "fpexcept.ignore".
Definition: FPEnv.h:39
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18
Value * simplifyAShrInst(Value *Op0, Value *Op1, bool IsExact, const SimplifyQuery &Q)
Given operands for a AShr, fold the result or return nulll.
Value * simplifyFMulInst(Value *LHS, Value *RHS, FastMathFlags FMF, const SimplifyQuery &Q, fp::ExceptionBehavior ExBehavior=fp::ebIgnore, RoundingMode Rounding=RoundingMode::NearestTiesToEven)
Given operands for an FMul, fold the result or return null.
Value * simplifyFreezeInst(Value *Op, const SimplifyQuery &Q)
Given an operand for a Freeze, see if we can fold the result.
Value * simplifySDivInst(Value *LHS, Value *RHS, bool IsExact, const SimplifyQuery &Q)
Given operands for an SDiv, fold the result or return null.
Value * simplifyUnOp(unsigned Opcode, Value *Op, const SimplifyQuery &Q)
Given operand for a UnaryOperator, fold the result or return null.
Value * simplifyMulInst(Value *LHS, Value *RHS, bool IsNSW, bool IsNUW, const SimplifyQuery &Q)
Given operands for a Mul, fold the result or return null.
Value * simplifyInstructionWithOperands(Instruction *I, ArrayRef< Value * > NewOps, const SimplifyQuery &Q)
Like simplifyInstruction but the operands of I are replaced with NewOps.
Value * simplifyCall(CallBase *Call, Value *Callee, ArrayRef< Value * > Args, const SimplifyQuery &Q)
Given a callsite, callee, and arguments, fold the result or return null.
Value * simplifyShuffleVectorInst(Value *Op0, Value *Op1, ArrayRef< int > Mask, Type *RetTy, const SimplifyQuery &Q)
Given operands for a ShuffleVectorInst, fold the result or return null.
Value * simplifyOrInst(Value *LHS, Value *RHS, const SimplifyQuery &Q)
Given operands for an Or, fold the result or return null.
Value * simplifyXorInst(Value *LHS, Value *RHS, const SimplifyQuery &Q)
Given operands for an Xor, fold the result or return null.
Value * simplifyCastInst(unsigned CastOpc, Value *Op, Type *Ty, const SimplifyQuery &Q)
Given operands for a CastInst, fold the result or return null.
Value * simplifyInstruction(Instruction *I, const SimplifyQuery &Q)
See if we can compute a simplified version of this instruction.
Value * simplifySubInst(Value *LHS, Value *RHS, bool IsNSW, bool IsNUW, const SimplifyQuery &Q)
Given operands for a Sub, fold the result or return null.
Value * simplifyAddInst(Value *LHS, Value *RHS, bool IsNSW, bool IsNUW, const SimplifyQuery &Q)
Given operands for an Add, fold the result or return null.
bool replaceAndRecursivelySimplify(Instruction *I, Value *SimpleV, const TargetLibraryInfo *TLI=nullptr, const DominatorTree *DT=nullptr, AssumptionCache *AC=nullptr, SmallSetVector< Instruction *, 8 > *UnsimplifiedUsers=nullptr)
Replace all uses of 'I' with 'SimpleV' and simplify the uses recursively.
Value * simplifyShlInst(Value *Op0, Value *Op1, bool IsNSW, bool IsNUW, const SimplifyQuery &Q)
Given operands for a Shl, fold the result or return null.
Value * simplifyFNegInst(Value *Op, FastMathFlags FMF, const SimplifyQuery &Q)
Given operand for an FNeg, fold the result or return null.
Value * simplifyFSubInst(Value *LHS, Value *RHS, FastMathFlags FMF, const SimplifyQuery &Q, fp::ExceptionBehavior ExBehavior=fp::ebIgnore, RoundingMode Rounding=RoundingMode::NearestTiesToEven)
Given operands for an FSub, fold the result or return null.
Value * simplifyFRemInst(Value *LHS, Value *RHS, FastMathFlags FMF, const SimplifyQuery &Q, fp::ExceptionBehavior ExBehavior=fp::ebIgnore, RoundingMode Rounding=RoundingMode::NearestTiesToEven)
Given operands for an FRem, fold the result or return null.
Value * simplifyFAddInst(Value *LHS, Value *RHS, FastMathFlags FMF, const SimplifyQuery &Q, fp::ExceptionBehavior ExBehavior=fp::ebIgnore, RoundingMode Rounding=RoundingMode::NearestTiesToEven)
Given operands for an FAdd, fold the result or return null.
Value * simplifyLShrInst(Value *Op0, Value *Op1, bool IsExact, const SimplifyQuery &Q)
Given operands for a LShr, fold the result or return null.
Value * simplifyAndInst(Value *LHS, Value *RHS, const SimplifyQuery &Q)
Given operands for an And, fold the result or return null.
Value * simplifyExtractValueInst(Value *Agg, ArrayRef< unsigned > Idxs, const SimplifyQuery &Q)
Given operands for an ExtractValueInst, fold the result or return null.
Value * simplifyInsertValueInst(Value *Agg, Value *Val, ArrayRef< unsigned > Idxs, const SimplifyQuery &Q)
Given operands for an InsertValueInst, fold the result or return null.
Value * simplifyICmpInst(unsigned Predicate, Value *LHS, Value *RHS, const SimplifyQuery &Q)
Given operands for an ICmpInst, fold the result or return null.
Value * simplifyFDivInst(Value *LHS, Value *RHS, FastMathFlags FMF, const SimplifyQuery &Q, fp::ExceptionBehavior ExBehavior=fp::ebIgnore, RoundingMode Rounding=RoundingMode::NearestTiesToEven)
Given operands for an FDiv, fold the result or return null.
Value * simplifyLoadInst(LoadInst *LI, Value *PtrOp, const SimplifyQuery &Q)
Given a load instruction and its pointer operand, fold the result or return null.
Value * simplifyFMAFMul(Value *LHS, Value *RHS, FastMathFlags FMF, const SimplifyQuery &Q, fp::ExceptionBehavior ExBehavior=fp::ebIgnore, RoundingMode Rounding=RoundingMode::NearestTiesToEven)
Given operands for the multiplication of a FMA, fold the result or return null.
Value * simplifyConstrainedFPCall(CallBase *Call, const SimplifyQuery &Q)
Given a constrained FP intrinsic call, tries to compute its simplified version.
Value * simplifyBinOp(unsigned Opcode, Value *LHS, Value *RHS, const SimplifyQuery &Q)
Given operands for a BinaryOperator, fold the result or return null.
Value * simplifyCmpInst(unsigned Predicate, Value *LHS, Value *RHS, const SimplifyQuery &Q)
Given operands for a CmpInst, fold the result or return null.
Value * simplifyUDivInst(Value *LHS, Value *RHS, bool IsExact, const SimplifyQuery &Q)
Given operands for a UDiv, fold the result or return null.
DWARFExpression::Operation Op
RoundingMode
Rounding mode.
@ NearestTiesToEven
roundTiesToEven.
ArrayRef(const T &OneElt) -> ArrayRef< T >
Value * simplifyInsertElementInst(Value *Vec, Value *Elt, Value *Idx, const SimplifyQuery &Q)
Given operands for an InsertElement, fold the result or return null.
Value * simplifyWithOpReplaced(Value *V, Value *Op, Value *RepOp, const SimplifyQuery &Q, bool AllowRefinement, SmallVectorImpl< Instruction * > *DropFlags=nullptr)
See if V simplifies when its operand Op is replaced with RepOp.
Value * simplifySRemInst(Value *LHS, Value *RHS, const SimplifyQuery &Q)
Given operands for an SRem, fold the result or return null.
const SimplifyQuery getBestSimplifyQuery(Pass &, Function &)
Value * simplifyFCmpInst(unsigned Predicate, Value *LHS, Value *RHS, FastMathFlags FMF, const SimplifyQuery &Q)
Given operands for an FCmpInst, fold the result or return null.
Value * simplifyGEPInst(Type *SrcTy, Value *Ptr, ArrayRef< Value * > Indices, bool InBounds, const SimplifyQuery &Q)
Given operands for a GetElementPtrInst, fold the result or return null.
Value * simplifyURemInst(Value *LHS, Value *RHS, const SimplifyQuery &Q)
Given operands for a URem, fold the result or return null.
Value * simplifyExtractElementInst(Value *Vec, Value *Idx, const SimplifyQuery &Q)
Given operands for an ExtractElementInst, fold the result or return null.
Value * simplifySelectInst(Value *Cond, Value *TrueVal, Value *FalseVal, const SimplifyQuery &Q)
Given operands for a SelectInst, fold the result or return null.