LLVM 18.0.0git
ValueSymbolTable.h
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1//===- llvm/ValueSymbolTable.h - Implement a Value Symtab -------*- 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 the name/Value symbol table for LLVM.
10//
11//===----------------------------------------------------------------------===//
12
13#ifndef LLVM_IR_VALUESYMBOLTABLE_H
14#define LLVM_IR_VALUESYMBOLTABLE_H
15
16#include "llvm/ADT/StringMap.h"
17#include "llvm/ADT/StringRef.h"
18#include "llvm/IR/Value.h"
19#include <cstdint>
20
21namespace llvm {
22
23class Argument;
24class BasicBlock;
25class Function;
26class GlobalAlias;
27class GlobalIFunc;
28class GlobalVariable;
29class Instruction;
30template <unsigned InternalLen> class SmallString;
31template <typename ValueSubClass> class SymbolTableListTraits;
32
33/// This class provides a symbol table of name/value pairs. It is essentially
34/// a std::map<std::string,Value*> but has a controlled interface provided by
35/// LLVM as well as ensuring uniqueness of names.
36///
38 friend class SymbolTableListTraits<Argument>;
40 friend class SymbolTableListTraits<Function>;
45 friend class Value;
46
47/// @name Types
48/// @{
49public:
50 /// A mapping of names to values.
52
53 /// An iterator over a ValueMap.
55
56 /// A const_iterator over a ValueMap.
58
59/// @}
60/// @name Constructors
61/// @{
62
63 ValueSymbolTable(int MaxNameSize = -1) : vmap(0), MaxNameSize(MaxNameSize) {}
65
66 /// @}
67 /// @name Accessors
68 /// @{
69
70 /// This method finds the value with the given \p Name in the
71 /// the symbol table.
72 /// @returns the value associated with the \p Name
73 /// Lookup a named Value.
75 if (MaxNameSize > -1 && Name.size() > (unsigned)MaxNameSize)
76 Name = Name.substr(0, std::max(1u, (unsigned)MaxNameSize));
77
78 return vmap.lookup(Name);
79 }
80
81 /// @returns true iff the symbol table is empty
82 /// Determine if the symbol table is empty
83 inline bool empty() const { return vmap.empty(); }
84
85 /// The number of name/type pairs is returned.
86 inline unsigned size() const { return unsigned(vmap.size()); }
87
88 /// This function can be used from the debugger to display the
89 /// content of the symbol table while debugging.
90 /// Print out symbol table on stderr
91 void dump() const;
92
93/// @}
94/// @name Iteration
95/// @{
96
97 /// Get an iterator that from the beginning of the symbol table.
98 inline iterator begin() { return vmap.begin(); }
99
100 /// Get a const_iterator that from the beginning of the symbol table.
101 inline const_iterator begin() const { return vmap.begin(); }
102
103 /// Get an iterator to the end of the symbol table.
104 inline iterator end() { return vmap.end(); }
105
106 /// Get a const_iterator to the end of the symbol table.
107 inline const_iterator end() const { return vmap.end(); }
108
109 /// @}
110 /// @name Mutators
111 /// @{
112private:
113 ValueName *makeUniqueName(Value *V, SmallString<256> &UniqueName);
114
115 /// This method adds the provided value \p N to the symbol table. The Value
116 /// must have a name which is used to place the value in the symbol table.
117 /// If the inserted name conflicts, this renames the value.
118 /// Add a named value to the symbol table
119 void reinsertValue(Value *V);
120
121 /// createValueName - This method attempts to create a value name and insert
122 /// it into the symbol table with the specified name. If it conflicts, it
123 /// auto-renames the name and returns that instead.
124 ValueName *createValueName(StringRef Name, Value *V);
125
126 /// This method removes a value from the symbol table. It leaves the
127 /// ValueName attached to the value, but it is no longer inserted in the
128 /// symtab.
129 void removeValueName(ValueName *V);
130
131 /// @}
132 /// @name Internal Data
133 /// @{
134
135 ValueMap vmap; ///< The map that holds the symbol table.
136 int MaxNameSize; ///< The maximum size for each name. If the limit is
137 ///< exceeded, the name is capped.
138 mutable uint32_t LastUnique = 0; ///< Counter for tracking unique names
139
140/// @}
141};
142
143} // end namespace llvm
144
145#endif // LLVM_IR_VALUESYMBOLTABLE_H
This file defines the StringMap class.
std::string Name
This class represents an incoming formal argument to a Function.
Definition: Argument.h:28
LLVM Basic Block Representation.
Definition: BasicBlock.h:56
SmallString - A SmallString is just a SmallVector with methods and accessors that make it work better...
Definition: SmallString.h:26
StringMapEntry - This is used to represent one value that is inserted into a StringMap.
unsigned size() const
Definition: StringMap.h:95
bool empty() const
Definition: StringMap.h:94
StringMapConstIterator< Value * > const_iterator
Definition: StringMap.h:201
iterator end()
Definition: StringMap.h:205
iterator begin()
Definition: StringMap.h:204
StringMapIterator< Value * > iterator
Definition: StringMap.h:202
ValueTy lookup(StringRef Key) const
lookup - Return the entry for the specified key, or a default constructed value if no such entry exis...
Definition: StringMap.h:234
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:50
See the file comment.
Definition: ValueMap.h:84
This class provides a symbol table of name/value pairs.
ValueSymbolTable(int MaxNameSize=-1)
void dump() const
This function can be used from the debugger to display the content of the symbol table while debuggin...
const_iterator begin() const
Get a const_iterator that from the beginning of the symbol table.
Value * lookup(StringRef Name) const
This method finds the value with the given Name in the the symbol table.
const_iterator end() const
Get a const_iterator to the end of the symbol table.
iterator end()
Get an iterator to the end of the symbol table.
unsigned size() const
The number of name/type pairs is returned.
iterator begin()
Get an iterator that from the beginning of the symbol table.
LLVM Value Representation.
Definition: Value.h:74
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18