LLVM  14.0.0git
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 
21 namespace llvm {
22 
23 class Argument;
24 class BasicBlock;
25 class Function;
26 class GlobalAlias;
27 class GlobalIFunc;
28 class GlobalVariable;
29 class Instruction;
30 template <unsigned InternalLen> class SmallString;
31 template <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 ///
45  friend class Value;
46 
47 /// @name Types
48 /// @{
49 public:
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  /// @{
112 private:
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
llvm::Argument
This class represents an incoming formal argument to a Function.
Definition: Argument.h:29
llvm::ValueSymbolTable::ValueSymbolTable
ValueSymbolTable(int MaxNameSize=-1)
Definition: ValueSymbolTable.h:63
llvm::ValueSymbolTable::empty
bool empty() const
Definition: ValueSymbolTable.h:83
llvm
---------------------— PointerInfo ------------------------------------—
Definition: AllocatorList.h:23
llvm::StringMapEntry
StringMapEntry - This is used to represent one value that is inserted into a StringMap.
Definition: StringMapEntry.h:98
llvm::Function
Definition: Function.h:61
StringRef.h
llvm::ValueSymbolTable::begin
iterator begin()
Get an iterator that from the beginning of the symbol table.
Definition: ValueSymbolTable.h:98
llvm::GlobalVariable
Definition: GlobalVariable.h:40
llvm::GlobalAlias
Definition: GlobalAlias.h:27
llvm::StringMap::end
iterator end()
Definition: StringMap.h:205
llvm::ValueSymbolTable::begin
const_iterator begin() const
Get a const_iterator that from the beginning of the symbol table.
Definition: ValueSymbolTable.h:101
llvm::BasicBlock
LLVM Basic Block Representation.
Definition: BasicBlock.h:58
llvm::StringMap< Value * >::iterator
StringMapIterator< Value * > iterator
Definition: StringMap.h:202
llvm::ValueSymbolTable::end
iterator end()
Get an iterator to the end of the symbol table.
Definition: ValueSymbolTable.h:104
llvm::StringMapConstIterator
Definition: StringMap.h:24
llvm::Instruction
Definition: Instruction.h:45
llvm::ValueSymbolTable::size
unsigned size() const
The number of name/type pairs is returned.
Definition: ValueSymbolTable.h:86
StringMap.h
llvm::StringMap< Value * >
llvm::SmallString< 256 >
llvm::StringMapIterator
Definition: StringMap.h:25
llvm::SymbolTableListTraits
Definition: GlobalAlias.h:25
llvm::StringMap::lookup
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
llvm::ValueSymbolTable::end
const_iterator end() const
Get a const_iterator to the end of the symbol table.
Definition: ValueSymbolTable.h:107
llvm::StringMap::begin
iterator begin()
Definition: StringMap.h:204
llvm::ISD::BasicBlock
@ BasicBlock
Various leaf nodes.
Definition: ISDOpcodes.h:71
llvm::StringMapImpl::size
unsigned size() const
Definition: StringMap.h:93
llvm::ValueSymbolTable::~ValueSymbolTable
~ValueSymbolTable()
Definition: ValueSymbolTable.cpp:33
llvm::StringRef
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:58
llvm::ValueSymbolTable::dump
void dump() const
This function can be used from the debugger to display the content of the symbol table while debuggin...
Definition: ValueSymbolTable.cpp:122
uint32_t
llvm::ValueMap
See the file comment.
Definition: ValueMap.h:85
llvm::GraphProgram::Name
Name
Definition: GraphWriter.h:52
llvm::StringMapImpl::empty
bool empty() const
Definition: StringMap.h:92
llvm::ValueSymbolTable
This class provides a symbol table of name/value pairs.
Definition: ValueSymbolTable.h:37
llvm::max
Align max(MaybeAlign Lhs, Align Rhs)
Definition: Alignment.h:340
llvm::ValueSymbolTable::lookup
Value * lookup(StringRef Name) const
This method finds the value with the given Name in the the symbol table.
Definition: ValueSymbolTable.h:74
llvm::StringMap< Value * >::const_iterator
StringMapConstIterator< Value * > const_iterator
Definition: StringMap.h:201
Value.h
llvm::GlobalIFunc
Definition: GlobalIFunc.h:32
llvm::Value
LLVM Value Representation.
Definition: Value.h:75
llvm::codeview::PublicSymFlags::Function
@ Function