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/// 37class ValueSymbolTable { 38 friend class SymbolTableListTraits<Argument>; 39 friend class SymbolTableListTraits<BasicBlock>; 40 friend class SymbolTableListTraits<Function>; 41 friend class SymbolTableListTraits<GlobalAlias>; 42 friend class SymbolTableListTraits<GlobalIFunc>; 43 friend class SymbolTableListTraits<GlobalVariable>; 44 friend class SymbolTableListTraits<Instruction>; 45 friend class Value; 46 47/// @name Types 48/// @{ 49public: 50 /// A mapping of names to values. 51 using ValueMap = StringMap<Value*>; 52 53 /// An iterator over a ValueMap. 54 using iterator = ValueMap::iterator; 55 56 /// A const_iterator over a ValueMap. 57 using const_iterator = ValueMap::const_iterator; 58 59/// @} 60/// @name Constructors 61/// @{ 62 63 ValueSymbolTable() : vmap(0) {} 64 ~ValueSymbolTable(); 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 /// @{ 107private: 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 139