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//===-- llvm/ADT/UniqueVector.h ---------------------------------*- C++ -*-===//
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// The LLVM Compiler Infrastructure
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//===----------------------------------------------------------------------===//
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#ifndef LLVM_ADT_UNIQUEVECTOR_H
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#define LLVM_ADT_UNIQUEVECTOR_H
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//===----------------------------------------------------------------------===//
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/// UniqueVector - This class produces a sequential ID number (base 1) for each
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/// unique entry that is added. T is the type of entries in the vector. This
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/// class should have an implementation of operator== and of operator<.
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/// Entries can be fetched using operator[] with the entry ID.
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template<class T> class UniqueVector {
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// Map - Used to handle the correspondence of entry to ID.
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std::map<T, unsigned> Map;
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// Vector - ID ordered vector of entries. Entries can be indexed by ID - 1.
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std::vector<T> Vector;
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/// insert - Append entry to the vector if it doesn't already exist. Returns
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/// the entry's index + 1 to be used as a unique ID.
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unsigned insert(const T &Entry) {
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// Check if the entry is already in the map.
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unsigned &Val = Map[Entry];
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// See if entry exists, if so return prior ID.
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// Compute ID for entry.
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Val = static_cast<unsigned>(Vector.size()) + 1;
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Vector.push_back(Entry);
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/// idFor - return the ID for an existing entry. Returns 0 if the entry is
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unsigned idFor(const T &Entry) const {
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// Search for entry in the map.
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typename std::map<T, unsigned>::const_iterator MI = Map.find(Entry);
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// See if entry exists, if so return ID.
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if (MI != Map.end()) return MI->second;
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/// operator[] - Returns a reference to the entry with the specified ID.
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const T &operator[](unsigned ID) const {
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assert(ID-1 < size() && "ID is 0 or out of range!");
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return Vector[ID - 1];
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/// size - Returns the number of entries in the vector.
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size_t size() const { return Vector.size(); }
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/// empty - Returns true if the vector is empty.
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bool empty() const { return Vector.empty(); }
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/// reset - Clears all the entries.
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} // End of namespace llvm
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#endif // LLVM_ADT_UNIQUEVECTOR_H