• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 //===-- llvm/ValueSymbolTable.h - Implement a Value Symtab ------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file implements the name/Value symbol table for LLVM.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_IR_VALUESYMBOLTABLE_H
15 #define LLVM_IR_VALUESYMBOLTABLE_H
16 
17 #include "llvm/ADT/StringMap.h"
18 #include "llvm/IR/Value.h"
19 #include "llvm/Support/DataTypes.h"
20 
21 namespace llvm {
22   template <typename ValueSubClass> class SymbolTableListTraits;
23   template <unsigned InternalLen> class SmallString;
24   class BasicBlock;
25   class Function;
26   class NamedMDNode;
27   class Module;
28   class StringRef;
29 
30 /// This class provides a symbol table of name/value pairs. It is essentially
31 /// a std::map<std::string,Value*> but has a controlled interface provided by
32 /// LLVM as well as ensuring uniqueness of names.
33 ///
34 class ValueSymbolTable {
35   friend class Value;
36   friend class SymbolTableListTraits<Argument>;
37   friend class SymbolTableListTraits<BasicBlock>;
38   friend class SymbolTableListTraits<Instruction>;
39   friend class SymbolTableListTraits<Function>;
40   friend class SymbolTableListTraits<GlobalVariable>;
41   friend class SymbolTableListTraits<GlobalAlias>;
42   friend class SymbolTableListTraits<GlobalIFunc>;
43 /// @name Types
44 /// @{
45 public:
46   /// @brief A mapping of names to values.
47   typedef StringMap<Value*> ValueMap;
48 
49   /// @brief An iterator over a ValueMap.
50   typedef ValueMap::iterator iterator;
51 
52   /// @brief A const_iterator over a ValueMap.
53   typedef ValueMap::const_iterator const_iterator;
54 
55 /// @}
56 /// @name Constructors
57 /// @{
58 public:
ValueSymbolTable()59   ValueSymbolTable() : vmap(0), LastUnique(0) {}
60   ~ValueSymbolTable();
61 
62 /// @}
63 /// @name Accessors
64 /// @{
65 public:
66   /// This method finds the value with the given \p Name in the
67   /// the symbol table.
68   /// @returns the value associated with the \p Name
69   /// @brief Lookup a named Value.
lookup(StringRef Name)70   Value *lookup(StringRef Name) const { return vmap.lookup(Name); }
71 
72   /// @returns true iff the symbol table is empty
73   /// @brief Determine if the symbol table is empty
empty()74   inline bool empty() const { return vmap.empty(); }
75 
76   /// @brief The number of name/type pairs is returned.
size()77   inline unsigned size() const { return unsigned(vmap.size()); }
78 
79   /// This function can be used from the debugger to display the
80   /// content of the symbol table while debugging.
81   /// @brief Print out symbol table on stderr
82   void dump() const;
83 
84 /// @}
85 /// @name Iteration
86 /// @{
87 public:
88   /// @brief Get an iterator that from the beginning of the symbol table.
begin()89   inline iterator begin() { return vmap.begin(); }
90 
91   /// @brief Get a const_iterator that from the beginning of the symbol table.
begin()92   inline const_iterator begin() const { return vmap.begin(); }
93 
94   /// @brief Get an iterator to the end of the symbol table.
end()95   inline iterator end() { return vmap.end(); }
96 
97   /// @brief Get a const_iterator to the end of the symbol table.
end()98   inline const_iterator end() const { return vmap.end(); }
99 
100   /// @}
101   /// @name Mutators
102   /// @{
103 private:
104   ValueName *makeUniqueName(Value *V, SmallString<256> &UniqueName);
105 
106   /// This method adds the provided value \p N to the symbol table.  The Value
107   /// must have a name which is used to place the value in the symbol table.
108   /// If the inserted name conflicts, this renames the value.
109   /// @brief Add a named value to the symbol table
110   void reinsertValue(Value *V);
111 
112   /// createValueName - This method attempts to create a value name and insert
113   /// it into the symbol table with the specified name.  If it conflicts, it
114   /// auto-renames the name and returns that instead.
115   ValueName *createValueName(StringRef Name, Value *V);
116 
117   /// This method removes a value from the symbol table.  It leaves the
118   /// ValueName attached to the value, but it is no longer inserted in the
119   /// symtab.
120   void removeValueName(ValueName *V);
121 
122   /// @}
123   /// @name Internal Data
124   /// @{
125 private:
126   ValueMap vmap;                    ///< The map that holds the symbol table.
127   mutable uint32_t LastUnique; ///< Counter for tracking unique names
128 
129 /// @}
130 };
131 
132 } // End llvm namespace
133 
134 #endif
135