• 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/SmallString.h"
18 #include "llvm/ADT/StringMap.h"
19 #include "llvm/IR/Value.h"
20 #include "llvm/Support/DataTypes.h"
21 
22 namespace llvm {
23   template <typename ValueSubClass> class SymbolTableListTraits;
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 /// @name Types
43 /// @{
44 public:
45   /// @brief A mapping of names to values.
46   typedef StringMap<Value*> ValueMap;
47 
48   /// @brief An iterator over a ValueMap.
49   typedef ValueMap::iterator iterator;
50 
51   /// @brief A const_iterator over a ValueMap.
52   typedef ValueMap::const_iterator const_iterator;
53 
54 /// @}
55 /// @name Constructors
56 /// @{
57 public:
ValueSymbolTable()58   ValueSymbolTable() : vmap(0), LastUnique(0) {}
59   ~ValueSymbolTable();
60 
61 /// @}
62 /// @name Accessors
63 /// @{
64 public:
65   /// This method finds the value with the given \p Name in the
66   /// the symbol table.
67   /// @returns the value associated with the \p Name
68   /// @brief Lookup a named Value.
lookup(StringRef Name)69   Value *lookup(StringRef Name) const { return vmap.lookup(Name); }
70 
71   /// @returns true iff the symbol table is empty
72   /// @brief Determine if the symbol table is empty
empty()73   inline bool empty() const { return vmap.empty(); }
74 
75   /// @brief The number of name/type pairs is returned.
size()76   inline unsigned size() const { return unsigned(vmap.size()); }
77 
78   /// This function can be used from the debugger to display the
79   /// content of the symbol table while debugging.
80   /// @brief Print out symbol table on stderr
81   void dump() const;
82 
83 /// @}
84 /// @name Iteration
85 /// @{
86 public:
87   /// @brief Get an iterator that from the beginning of the symbol table.
begin()88   inline iterator begin() { return vmap.begin(); }
89 
90   /// @brief Get a const_iterator that from the beginning of the symbol table.
begin()91   inline const_iterator begin() const { return vmap.begin(); }
92 
93   /// @brief Get an iterator to the end of the symbol table.
end()94   inline iterator end() { return vmap.end(); }
95 
96   /// @brief Get a const_iterator to the end of the symbol table.
end()97   inline const_iterator end() const { return vmap.end(); }
98 
99   /// @}
100   /// @name Mutators
101   /// @{
102 private:
103   ValueName *makeUniqueName(Value *V, SmallString<256> &UniqueName);
104 
105   /// This method adds the provided value \p N to the symbol table.  The Value
106   /// must have a name which is used to place the value in the symbol table.
107   /// If the inserted name conflicts, this renames the value.
108   /// @brief Add a named value to the symbol table
109   void reinsertValue(Value *V);
110 
111   /// createValueName - This method attempts to create a value name and insert
112   /// it into the symbol table with the specified name.  If it conflicts, it
113   /// auto-renames the name and returns that instead.
114   ValueName *createValueName(StringRef Name, Value *V);
115 
116   /// This method removes a value from the symbol table.  It leaves the
117   /// ValueName attached to the value, but it is no longer inserted in the
118   /// symtab.
119   void removeValueName(ValueName *V);
120 
121   /// @}
122   /// @name Internal Data
123   /// @{
124 private:
125   ValueMap vmap;                    ///< The map that holds the symbol table.
126   mutable uint32_t LastUnique; ///< Counter for tracking unique names
127 
128 /// @}
129 };
130 
131 } // End llvm namespace
132 
133 #endif
134