LLVM 17.0.0git
IVUsers.h
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1//===- llvm/Analysis/IVUsers.h - Induction Variable Users -------*- 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 implements bookkeeping for "interesting" users of expressions
10// computed from induction variables.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_ANALYSIS_IVUSERS_H
15#define LLVM_ANALYSIS_IVUSERS_H
16
20#include "llvm/IR/ValueHandle.h"
21
22namespace llvm {
23
24class AssumptionCache;
25class DominatorTree;
26class ScalarEvolution;
27class SCEV;
28class IVUsers;
29
30/// IVStrideUse - Keep track of one use of a strided induction variable.
31/// The Expr member keeps track of the expression, User is the actual user
32/// instruction of the operand, and 'OperandValToReplace' is the operand of
33/// the User that is the use.
34class IVStrideUse final : public CallbackVH, public ilist_node<IVStrideUse> {
35 friend class IVUsers;
36public:
38 : CallbackVH(U), Parent(P), OperandValToReplace(O) {
39 }
40
41 /// getUser - Return the user instruction for this use.
43 return cast<Instruction>(getValPtr());
44 }
45
46 /// setUser - Assign a new user instruction for this use.
47 void setUser(Instruction *NewUser) {
48 setValPtr(NewUser);
49 }
50
51 /// getOperandValToReplace - Return the Value of the operand in the user
52 /// instruction that this IVStrideUse is representing.
54 return OperandValToReplace;
55 }
56
57 /// setOperandValToReplace - Assign a new Value as the operand value
58 /// to replace.
60 OperandValToReplace = Op;
61 }
62
63 /// getPostIncLoops - Return the set of loops for which the expression has
64 /// been adjusted to use post-inc mode.
66 return PostIncLoops;
67 }
68
69 /// transformToPostInc - Transform the expression to post-inc form for the
70 /// given loop.
71 void transformToPostInc(const Loop *L);
72
73private:
74 /// Parent - a pointer to the IVUsers that owns this IVStrideUse.
75 IVUsers *Parent;
76
77 /// OperandValToReplace - The Value of the operand in the user instruction
78 /// that this IVStrideUse is representing.
79 WeakTrackingVH OperandValToReplace;
80
81 /// PostIncLoops - The set of loops for which Expr has been adjusted to
82 /// use post-inc mode. This corresponds with SCEVExpander's post-inc concept.
83 PostIncLoopSet PostIncLoops;
84
85 /// Deleted - Implementation of CallbackVH virtual function to
86 /// receive notification when the User is deleted.
87 void deleted() override;
88};
89
90class IVUsers {
91 friend class IVStrideUse;
92 Loop *L;
94 LoopInfo *LI;
95 DominatorTree *DT;
98
99 /// IVUses - A list of all tracked IV uses of induction variable expressions
100 /// we are interested in.
101 ilist<IVStrideUse> IVUses;
102
103 // Ephemeral values used by @llvm.assume in this function.
105
106public:
108 ScalarEvolution *SE);
109
111 : L(std::move(X.L)), AC(std::move(X.AC)), DT(std::move(X.DT)),
112 SE(std::move(X.SE)), Processed(std::move(X.Processed)),
113 IVUses(std::move(X.IVUses)), EphValues(std::move(X.EphValues)) {
114 for (IVStrideUse &U : IVUses)
115 U.Parent = this;
116 }
117 IVUsers(const IVUsers &) = delete;
118 IVUsers &operator=(IVUsers &&) = delete;
119 IVUsers &operator=(const IVUsers &) = delete;
120
121 Loop *getLoop() const { return L; }
122
123 /// AddUsersIfInteresting - Inspect the specified Instruction. If it is a
124 /// reducible SCEV, recursively add its users to the IVUsesByStride set and
125 /// return true. Otherwise, return false.
127
129
130 /// getReplacementExpr - Return a SCEV expression which computes the
131 /// value of the OperandValToReplace of the given IVStrideUse.
132 const SCEV *getReplacementExpr(const IVStrideUse &IU) const;
133
134 /// getExpr - Return the expression for the use.
135 const SCEV *getExpr(const IVStrideUse &IU) const;
136
137 const SCEV *getStride(const IVStrideUse &IU, const Loop *L) const;
138
141 iterator begin() { return IVUses.begin(); }
142 iterator end() { return IVUses.end(); }
143 const_iterator begin() const { return IVUses.begin(); }
144 const_iterator end() const { return IVUses.end(); }
145 bool empty() const { return IVUses.empty(); }
146
147 bool isIVUserOrOperand(Instruction *Inst) const {
148 return Processed.count(Inst);
149 }
150
151 void releaseMemory();
152
153 void print(raw_ostream &OS, const Module * = nullptr) const;
154
155 /// dump - This method is used for debugging.
156 void dump() const;
157};
158
160
162 std::unique_ptr<IVUsers> IU;
163
164public:
165 static char ID;
166
168
169 IVUsers &getIU() { return *IU; }
170 const IVUsers &getIU() const { return *IU; }
171
172 void getAnalysisUsage(AnalysisUsage &AU) const override;
173
174 bool runOnLoop(Loop *L, LPPassManager &LPM) override;
175
176 void releaseMemory() override;
177
178 void print(raw_ostream &OS, const Module * = nullptr) const override;
179};
180
181/// Analysis pass that exposes the \c IVUsers for a loop.
182class IVUsersAnalysis : public AnalysisInfoMixin<IVUsersAnalysis> {
184 static AnalysisKey Key;
185
186public:
188
191};
192
193}
194
195#endif
static GCMetadataPrinterRegistry::Add< ErlangGCPrinter > X("erlang", "erlang-compatible garbage collector")
print lazy value Lazy Value Info Printer Pass
This header provides classes for managing per-loop analyses.
#define I(x, y, z)
Definition: MD5.cpp:58
#define P(N)
A container for analyses that lazily runs them and caches their results.
Definition: PassManager.h:620
Represent the analysis usage information of a pass.
A cache of @llvm.assume calls within a function.
Value handle with callbacks on RAUW and destruction.
Definition: ValueHandle.h:383
void setValPtr(Value *P)
Definition: ValueHandle.h:390
Concrete subclass of DominatorTreeBase that is used to compute a normal dominator tree.
Definition: Dominators.h:166
IVStrideUse - Keep track of one use of a strided induction variable.
Definition: IVUsers.h:34
Instruction * getUser() const
getUser - Return the user instruction for this use.
Definition: IVUsers.h:42
void setOperandValToReplace(Value *Op)
setOperandValToReplace - Assign a new Value as the operand value to replace.
Definition: IVUsers.h:59
const PostIncLoopSet & getPostIncLoops() const
getPostIncLoops - Return the set of loops for which the expression has been adjusted to use post-inc ...
Definition: IVUsers.h:65
void transformToPostInc(const Loop *L)
transformToPostInc - Transform the expression to post-inc form for the given loop.
Definition: IVUsers.cpp:364
Value * getOperandValToReplace() const
getOperandValToReplace - Return the Value of the operand in the user instruction that this IVStrideUs...
Definition: IVUsers.h:53
IVStrideUse(IVUsers *P, Instruction *U, Value *O)
Definition: IVUsers.h:37
void setUser(Instruction *NewUser)
setUser - Assign a new user instruction for this use.
Definition: IVUsers.h:47
Analysis pass that exposes the IVUsers for a loop.
Definition: IVUsers.h:182
IVUsers run(Loop &L, LoopAnalysisManager &AM, LoopStandardAnalysisResults &AR)
Definition: IVUsers.cpp:36
void getAnalysisUsage(AnalysisUsage &AU) const override
getAnalysisUsage - This function should be overriden by passes that need analysis information to do t...
Definition: IVUsers.cpp:304
bool runOnLoop(Loop *L, LPPassManager &LPM) override
Definition: IVUsers.cpp:312
void print(raw_ostream &OS, const Module *=nullptr) const override
print - Print out the internal state of the pass.
Definition: IVUsers.cpp:323
void releaseMemory() override
releaseMemory() - This member can be implemented by a pass if it wants to be able to release its memo...
Definition: IVUsers.cpp:327
const IVUsers & getIU() const
Definition: IVUsers.h:170
void dump() const
dump - This method is used for debugging.
Definition: IVUsers.cpp:292
ilist< IVStrideUse >::const_iterator const_iterator
Definition: IVUsers.h:140
bool isIVUserOrOperand(Instruction *Inst) const
Definition: IVUsers.h:147
iterator end()
Definition: IVUsers.h:142
IVStrideUse & AddUser(Instruction *User, Value *Operand)
Definition: IVUsers.cpp:246
void releaseMemory()
Definition: IVUsers.cpp:295
Loop * getLoop() const
Definition: IVUsers.h:121
IVUsers & operator=(IVUsers &&)=delete
const SCEV * getStride(const IVStrideUse &IU, const Loop *L) const
Definition: IVUsers.cpp:358
IVUsers(const IVUsers &)=delete
const SCEV * getReplacementExpr(const IVStrideUse &IU) const
getReplacementExpr - Return a SCEV expression which computes the value of the OperandValToReplace of ...
Definition: IVUsers.cpp:331
IVUsers(IVUsers &&X)
Definition: IVUsers.h:110
iterator begin()
Definition: IVUsers.h:141
bool AddUsersIfInteresting(Instruction *I)
AddUsersIfInteresting - Inspect the specified Instruction.
Definition: IVUsers.cpp:136
const_iterator end() const
Definition: IVUsers.h:144
ilist< IVStrideUse >::iterator iterator
Definition: IVUsers.h:139
const_iterator begin() const
Definition: IVUsers.h:143
const SCEV * getExpr(const IVStrideUse &IU) const
getExpr - Return the expression for the use.
Definition: IVUsers.cpp:336
IVUsers & operator=(const IVUsers &)=delete
void print(raw_ostream &OS, const Module *=nullptr) const
Definition: IVUsers.cpp:265
bool empty() const
Definition: IVUsers.h:145
Represents a single loop in the control flow graph.
Definition: LoopInfo.h:547
A Module instance is used to store all the information related to an LLVM module.
Definition: Module.h:65
This class represents an analyzed expression in the program.
The main scalar evolution driver.
size_type count(ConstPtrType Ptr) const
count - Return 1 if the specified pointer is in the set, 0 otherwise.
Definition: SmallPtrSet.h:383
Value * getValPtr() const
Definition: ValueHandle.h:99
LLVM Value Representation.
Definition: Value.h:74
Value handle that is nullable, but tries to track the Value.
Definition: ValueHandle.h:204
Iterator for intrusive lists based on ilist_node.
An intrusive list with ownership and callbacks specified/controlled by ilist_traits,...
Definition: ilist.h:392
This class implements an extremely fast bulk output stream that can only output to a stream.
Definition: raw_ostream.h:52
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18
Pass * createIVUsersPass()
Definition: IVUsers.cpp:51
OutputIt move(R &&Range, OutputIt Out)
Provide wrappers to std::move which take ranges instead of having to pass begin/end explicitly.
Definition: STLExtras.h:1862
Definition: BitVector.h:851
A CRTP mix-in that provides informational APIs needed for analysis passes.
Definition: PassManager.h:394
A special type used by analysis passes to provide an address that identifies that particular analysis...
Definition: PassManager.h:69
The adaptor from a function pass to a loop pass computes these analyses and makes them available to t...