For PR411:

First step in refactoring the SymbolTable is to split it into two classes,
one for a symbol table of types and one for a symbol table of Values.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25175 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 152 insertions, 0 deletions

diff --git a/include/llvm/TypeSymbolTable.h b/include/llvm/TypeSymbolTable.h
new file mode 100644
index 0000000000..6511be03db
--- /dev/null
+++ b/include/llvm/TypeSymbolTable.h
@@ -0,0 +1,152 @@
+//===-- llvm/TypeSymbolTable.h - Implement a Type Symtab --------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by Reid Spencer based on the original SymbolTable
+// implemented by the LLVM Research Group and re-written by Reid Spencer.
+// It is distributed under the University of Illinois Open Source License. 
+// See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the name/type symbol table for LLVM.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_TYPE_SYMBOL_TABLE_H
+#define LLVM_TYPE_SYMBOL_TABLE_H
+
+#include "llvm/Type.h"
+#include <map>
+
+namespace llvm {
+
+/// This class provides a symbol table of name/type pairs with operations to
+/// support constructing, searching and iterating over the symbol table. The
+/// class derives from AbstractTypeUser so that the contents of the symbol
+/// table can be updated when abstract types become concrete.
+class TypeSymbolTable : public AbstractTypeUser {
+
+/// @name Types
+/// @{
+public:
+
+  /// @brief A mapping of names to types.
+  typedef std::map<const std::string, const Type*> TypeMap;
+
+  /// @brief An iterator over the TypeMap.
+  typedef TypeMap::iterator iterator;
+
+  /// @brief A const_iterator over the TypeMap.
+  typedef TypeMap::const_iterator const_iterator;
+
+/// @}
+/// @name Constructors
+/// @{
+public:
+
+  TypeSymbolTable() {}
+  ~TypeSymbolTable();
+
+/// @}
+/// @name Accessors
+/// @{
+public:
+
+  /// Generates a unique name for a type based on the \p BaseName by
+  /// incrementing an integer and appending it to the name, if necessary
+  /// @returns the unique name
+  /// @brief Get a unique name for a type
+  std::string getUniqueName(const std::string &BaseName) const;
+
+  /// This method finds the type with the given \p name in the type map
+  /// and returns it.
+  /// @returns null if the name is not found, otherwise the Type
+  /// associated with the \p name.
+  /// @brief Lookup a type by name.
+  Type* lookup(const std::string& name) const;
+
+  /// @returns true iff the symbol table is empty.
+  /// @brief Determine if the symbol table is empty
+  inline bool empty() const { return tmap.empty(); }
+
+  /// @returns the size of the symbol table
+  /// @brief The number of name/type pairs is returned.
+  inline unsigned size() const { return unsigned(tmap.size()); }
+
+  /// This function can be used from the debugger to display the
+  /// content of the symbol table while debugging.
+  /// @brief Print out symbol table on stderr
+  void dump() const;
+
+/// @}
+/// @name Iteration
+/// @{
+public:
+  /// Get an iterator to the start of the symbol table
+  inline iterator begin() { return tmap.begin(); }
+
+  /// @brief Get a const_iterator to the start of the symbol table
+  inline const_iterator begin() const { return tmap.begin(); }
+
+  /// Get an iterator to the end of the symbol talbe. 
+  inline iterator end() { return tmap.end(); }
+
+  /// Get a const_iterator to the end of the symbol table.
+  inline const_iterator end() const { return tmap.end(); }
+
+/// @}
+/// @name Mutators
+/// @{
+public:
+
+  /// This method will strip the symbol table of its names 
+  /// @brief Strip the symbol table.
+  bool strip();
+
+  /// Inserts a type into the symbol table with the specified name. There can be
+  /// a many-to-one mapping between names and types. This method allows a type
+  /// with an existing entry in the symbol table to get a new name.
+  /// @brief Insert a type under a new name.
+  void insert(const std::string &Name, const Type *Typ);
+
+  /// Remove a type at the specified position in the symbol table.
+  /// @returns the removed Type.
+  /// @returns the Type that was erased from the symbol table.
+  Type* erase(iterator TI);
+
+  /// Remove a specific Type from the symbol table. This isn't fast, linear
+  /// search, O(n), algorithm.
+  /// @returns true if the erase was successful (TI was found)
+  bool erase(Type* TI);
+
+  /// Rename a type. This ain't fast, we have to linearly search for it first.
+  /// @returns true if the rename was successful (type was found)
+  bool rename(Type* T, const std::string& new_name);
+
+/// @}
+/// @name AbstractTypeUser Methods
+/// @{
+private:
+  /// This function is called when one of the types in the type plane
+  /// is refined.
+  virtual void refineAbstractType(const DerivedType *OldTy, const Type *NewTy);
+
+  /// This function markes a type as being concrete (defined).
+  virtual void typeBecameConcrete(const DerivedType *AbsTy);
+
+/// @}
+/// @name Internal Data
+/// @{
+private:
+  TypeMap tmap; ///< This is the mapping of names to types.
+  mutable unsigned long LastUnique; ///< Counter for tracking unique names
+
+/// @}
+
+};
+
+} // End llvm namespace
+
+#endif
+