LLVM  10.0.0svn
ValueSymbolTable.h
Go to the documentation of this file.
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() : vmap(0) {}
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.
74  Value *lookup(StringRef Name) const { return vmap.lookup(Name); }
75 
76  /// @returns true iff the symbol table is empty
77  /// Determine if the symbol table is empty
78  inline bool empty() const { return vmap.empty(); }
79 
80  /// The number of name/type pairs is returned.
81  inline unsigned size() const { return unsigned(vmap.size()); }
82 
83  /// This function can be used from the debugger to display the
84  /// content of the symbol table while debugging.
85  /// Print out symbol table on stderr
86  void dump() const;
87 
88 /// @}
89 /// @name Iteration
90 /// @{
91 
92  /// Get an iterator that from the beginning of the symbol table.
93  inline iterator begin() { return vmap.begin(); }
94 
95  /// Get a const_iterator that from the beginning of the symbol table.
96  inline const_iterator begin() const { return vmap.begin(); }
97 
98  /// Get an iterator to the end of the symbol table.
99  inline iterator end() { return vmap.end(); }
100 
101  /// Get a const_iterator to the end of the symbol table.
102  inline const_iterator end() const { return vmap.end(); }
103 
104  /// @}
105  /// @name Mutators
106  /// @{
107 private:
108  ValueName *makeUniqueName(Value *V, SmallString<256> &UniqueName);
109 
110  /// This method adds the provided value \p N to the symbol table. The Value
111  /// must have a name which is used to place the value in the symbol table.
112  /// If the inserted name conflicts, this renames the value.
113  /// Add a named value to the symbol table
114  void reinsertValue(Value *V);
115 
116  /// createValueName - This method attempts to create a value name and insert
117  /// it into the symbol table with the specified name. If it conflicts, it
118  /// auto-renames the name and returns that instead.
119  ValueName *createValueName(StringRef Name, Value *V);
120 
121  /// This method removes a value from the symbol table. It leaves the
122  /// ValueName attached to the value, but it is no longer inserted in the
123  /// symtab.
124  void removeValueName(ValueName *V);
125 
126  /// @}
127  /// @name Internal Data
128  /// @{
129 
130  ValueMap vmap; ///< The map that holds the symbol table.
131  mutable uint32_t LastUnique = 0; ///< Counter for tracking unique names
132 
133 /// @}
134 };
135 
136 } // end namespace llvm
137 
138 #endif // LLVM_IR_VALUESYMBOLTABLE_H
This class provides a symbol table of name/value pairs.
This class represents an incoming formal argument to a Function.
Definition: Argument.h:29
iterator begin()
Get an iterator that from the beginning of the symbol table.
This class represents lattice values for constants.
Definition: AllocatorList.h:23
StringMapEntry - This is used to represent one value that is inserted into a StringMap.
Definition: StringMap.h:125
Various leaf nodes.
Definition: ISDOpcodes.h:59
amdgpu Simplify well known AMD library false FunctionCallee Value const Twine & Name
unsigned size() const
Definition: StringMap.h:111
unsigned size() const
The number of name/type pairs is returned.
iterator end()
Get an iterator to the end of the symbol table.
const_iterator end() const
Get a const_iterator to the end of the symbol table.
LLVM Basic Block Representation.
Definition: BasicBlock.h:57
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:346
const_iterator begin() const
Get a const_iterator that from the beginning of the symbol table.
StringMapIterator< ValueTy > iterator
Definition: StringMap.h:312
StringMap - This is an unconventional map that is specialized for handling keys that are "strings"...
Definition: StringMap.h:219
iterator begin()
Definition: StringMap.h:314
void dump() const
This function can be used from the debugger to display the content of the symbol table while debuggin...
Value * lookup(StringRef Name) const
This method finds the value with the given Name in the the symbol table.
bool empty() const
Definition: StringMap.h:110
LLVM Value Representation.
Definition: Value.h:73
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:48
StringMapConstIterator< ValueTy > const_iterator
Definition: StringMap.h:311
iterator end()
Definition: StringMap.h:317