UniqueVector.h revision e264f62ca09a8f65c87a46d562a4d0f9ec5d457
1e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao//===-- llvm/ADT/UniqueVector.h ---------------------------------*- C++ -*-===// 2e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao// 3e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao// The LLVM Compiler Infrastructure 4e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao// 5e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao// This file is distributed under the University of Illinois Open Source 6e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao// License. See LICENSE.TXT for details. 7e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao// 8e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao//===----------------------------------------------------------------------===// 9e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao 10e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao#ifndef LLVM_ADT_UNIQUEVECTOR_H 11e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao#define LLVM_ADT_UNIQUEVECTOR_H 12e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao 13e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao#include <cassert> 14e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao#include <map> 15e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao#include <vector> 16e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao 17e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liaonamespace llvm { 18e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao 19e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao//===----------------------------------------------------------------------===// 20e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao/// UniqueVector - This class produces a sequential ID number (base 1) for each 21e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao/// unique entry that is added. T is the type of entries in the vector. This 22e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao/// class should have an implementation of operator== and of operator<. 23e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao/// Entries can be fetched using operator[] with the entry ID. 24e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liaotemplate<class T> class UniqueVector { 25e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liaoprivate: 26e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // Map - Used to handle the correspondence of entry to ID. 27e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao std::map<T, unsigned> Map; 28e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao 29e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // Vector - ID ordered vector of entries. Entries can be indexed by ID - 1. 30e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // 31e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao std::vector<T> Vector; 32e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao 33e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liaopublic: 34e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao /// insert - Append entry to the vector if it doesn't already exist. Returns 35e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao /// the entry's index + 1 to be used as a unique ID. 36e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao unsigned insert(const T &Entry) { 37e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // Check if the entry is already in the map. 38e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao unsigned &Val = Map[Entry]; 39e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao 40e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // See if entry exists, if so return prior ID. 41e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao if (Val) return Val; 42e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao 43e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // Compute ID for entry. 44e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao Val = static_cast<unsigned>(Vector.size()) + 1; 45e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao 46e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // Insert in vector. 47e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao Vector.push_back(Entry); 48e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao return Val; 49e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao } 50e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao 51e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao /// idFor - return the ID for an existing entry. Returns 0 if the entry is 52e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao /// not found. 53e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao unsigned idFor(const T &Entry) const { 54e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // Search for entry in the map. 55e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao typename std::map<T, unsigned>::const_iterator MI = Map.find(Entry); 56e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao 57e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // See if entry exists, if so return ID. 58e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao if (MI != Map.end()) return MI->second; 59e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao 60e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao // No luck. 61e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao return 0; 62e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao } 63e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao 64e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao /// operator[] - Returns a reference to the entry with the specified ID. 65e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao /// 66e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao const T &operator[](unsigned ID) const { 67e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao assert(ID-1 < size() && "ID is 0 or out of range!"); 68e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao return Vector[ID - 1]; 69e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao } 70e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao 71e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao /// size - Returns the number of entries in the vector. 72e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao /// 73e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao size_t size() const { return Vector.size(); } 74e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao 75e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao /// empty - Returns true if the vector is empty. 76e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao /// 77e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao bool empty() const { return Vector.empty(); } 78e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao 79e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao /// reset - Clears all the entries. 80e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao /// 81e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao void reset() { 82e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao Map.clear(); 83e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao Vector.resize(0, 0); 84e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao } 85e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao}; 86e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao 87e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao} // End of namespace llvm 88e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao 89e264f62ca09a8f65c87a46d562a4d0f9ec5d457Shih-wei Liao#endif // LLVM_ADT_UNIQUEVECTOR_H 90