freebsd-dev/include/llvm/ADT/SetVector.h
2009-06-02 17:52:33 +00:00

169 lines
4.8 KiB
C++

//===- llvm/ADT/SetVector.h - Set with insert order iteration ---*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements a set that has insertion order iteration
// characteristics. This is useful for keeping a set of things that need to be
// visited later but in a deterministic order (insertion order). The interface
// is purposefully minimal.
//
// This file defines SetVector and SmallSetVector, which performs no allocations
// if the SetVector has less than a certain number of elements.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_ADT_SETVECTOR_H
#define LLVM_ADT_SETVECTOR_H
#include "llvm/ADT/SmallSet.h"
#include <algorithm>
#include <cassert>
#include <vector>
namespace llvm {
/// This adapter class provides a way to keep a set of things that also has the
/// property of a deterministic iteration order. The order of iteration is the
/// order of insertion.
/// @brief A vector that has set insertion semantics.
template <typename T, typename Vector = std::vector<T>,
typename Set = SmallSet<T, 16> >
class SetVector {
public:
typedef T value_type;
typedef T key_type;
typedef T& reference;
typedef const T& const_reference;
typedef Set set_type;
typedef Vector vector_type;
typedef typename vector_type::const_iterator iterator;
typedef typename vector_type::const_iterator const_iterator;
typedef typename vector_type::size_type size_type;
/// @brief Construct an empty SetVector
SetVector() {}
/// @brief Initialize a SetVector with a range of elements
template<typename It>
SetVector(It Start, It End) {
insert(Start, End);
}
/// @brief Determine if the SetVector is empty or not.
bool empty() const {
return vector_.empty();
}
/// @brief Determine the number of elements in the SetVector.
size_type size() const {
return vector_.size();
}
/// @brief Get an iterator to the beginning of the SetVector.
iterator begin() {
return vector_.begin();
}
/// @brief Get a const_iterator to the beginning of the SetVector.
const_iterator begin() const {
return vector_.begin();
}
/// @brief Get an iterator to the end of the SetVector.
iterator end() {
return vector_.end();
}
/// @brief Get a const_iterator to the end of the SetVector.
const_iterator end() const {
return vector_.end();
}
/// @brief Return the last element of the SetVector.
const T &back() const {
assert(!empty() && "Cannot call back() on empty SetVector!");
return vector_.back();
}
/// @brief Index into the SetVector.
const_reference operator[](size_type n) const {
assert(n < vector_.size() && "SetVector access out of range!");
return vector_[n];
}
/// @returns true iff the element was inserted into the SetVector.
/// @brief Insert a new element into the SetVector.
bool insert(const value_type &X) {
bool result = set_.insert(X);
if (result)
vector_.push_back(X);
return result;
}
/// @brief Insert a range of elements into the SetVector.
template<typename It>
void insert(It Start, It End) {
for (; Start != End; ++Start)
if (set_.insert(*Start))
vector_.push_back(*Start);
}
/// @brief Remove an item from the set vector.
void remove(const value_type& X) {
if (set_.erase(X)) {
typename vector_type::iterator I =
std::find(vector_.begin(), vector_.end(), X);
assert(I != vector_.end() && "Corrupted SetVector instances!");
vector_.erase(I);
}
}
/// @returns 0 if the element is not in the SetVector, 1 if it is.
/// @brief Count the number of elements of a given key in the SetVector.
size_type count(const key_type &key) const {
return set_.count(key);
}
/// @brief Completely clear the SetVector
void clear() {
set_.clear();
vector_.clear();
}
/// @brief Remove the last element of the SetVector.
void pop_back() {
assert(!empty() && "Cannot remove an element from an empty SetVector!");
set_.erase(back());
vector_.pop_back();
}
private:
set_type set_; ///< The set.
vector_type vector_; ///< The vector.
};
/// SmallSetVector - A SetVector that performs no allocations if smaller than
/// a certain size.
template <typename T, unsigned N>
class SmallSetVector : public SetVector<T, SmallVector<T, N>, SmallSet<T, N> > {
public:
SmallSetVector() {}
/// @brief Initialize a SmallSetVector with a range of elements
template<typename It>
SmallSetVector(It Start, It End) {
this->insert(Start, End);
}
};
} // End llvm namespace
// vim: sw=2 ai
#endif