YouCompleteMe/cpp/BoostParts/boost/unordered/detail/table.hpp
Strahinja Val Markovic 0f7f32d96f Updating to boost 1.50
2012-07-21 11:37:40 -07:00

453 lines
14 KiB
C++

// Copyright (C) 2003-2004 Jeremy B. Maitin-Shepard.
// Copyright (C) 2005-2011 Daniel James
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
#ifndef BOOST_UNORDERED_DETAIL_ALL_HPP_INCLUDED
#define BOOST_UNORDERED_DETAIL_ALL_HPP_INCLUDED
#include <boost/unordered/detail/buckets.hpp>
#include <boost/unordered/detail/util.hpp>
#include <boost/type_traits/aligned_storage.hpp>
#include <boost/type_traits/alignment_of.hpp>
#include <cmath>
namespace boost { namespace unordered { namespace detail {
////////////////////////////////////////////////////////////////////////////
// convert double to std::size_t
inline std::size_t double_to_size(double f)
{
return f >= static_cast<double>(
(std::numeric_limits<std::size_t>::max)()) ?
(std::numeric_limits<std::size_t>::max)() :
static_cast<std::size_t>(f);
}
// The space used to store values in a node.
template <typename ValueType>
struct value_base
{
typedef ValueType value_type;
typename boost::aligned_storage<
sizeof(value_type),
boost::alignment_of<value_type>::value>::type data_;
void* address() {
return this;
}
value_type& value() {
return *(ValueType*) this;
}
value_type* value_ptr() {
return (ValueType*) this;
}
private:
value_base& operator=(value_base const&);
};
template <typename Types>
struct table :
boost::unordered::detail::buckets<
typename Types::allocator,
typename Types::bucket,
typename Types::node,
typename Types::policy>,
boost::unordered::detail::functions<
typename Types::hasher,
typename Types::key_equal>
{
private:
table(table const&);
table& operator=(table const&);
public:
typedef typename Types::hasher hasher;
typedef typename Types::key_equal key_equal;
typedef typename Types::key_type key_type;
typedef typename Types::extractor extractor;
typedef typename Types::value_type value_type;
typedef typename Types::table table_impl;
typedef typename Types::link_pointer link_pointer;
typedef typename Types::policy policy;
typedef boost::unordered::detail::functions<
typename Types::hasher,
typename Types::key_equal> functions;
typedef boost::unordered::detail::buckets<
typename Types::allocator,
typename Types::bucket,
typename Types::node,
typename Types::policy> buckets;
typedef typename buckets::node_allocator node_allocator;
typedef typename buckets::node_allocator_traits node_allocator_traits;
typedef typename buckets::node_pointer node_pointer;
typedef typename buckets::const_node_pointer const_node_pointer;
typedef typename table::iterator iterator;
// Members
float mlf_;
std::size_t max_load_; // Only use if this->buckets_.
////////////////////////////////////////////////////////////////////////
// Load methods
std::size_t max_size() const
{
using namespace std;
// size < mlf_ * count
return boost::unordered::detail::double_to_size(ceil(
static_cast<double>(this->mlf_) *
static_cast<double>(this->max_bucket_count())
)) - 1;
}
std::size_t calculate_max_load()
{
using namespace std;
// From 6.3.1/13:
// Only resize when size >= mlf_ * count
return boost::unordered::detail::double_to_size(ceil(
static_cast<double>(this->mlf_) *
static_cast<double>(this->bucket_count_)
));
}
void max_load_factor(float z)
{
BOOST_ASSERT(z > 0);
mlf_ = (std::max)(z, minimum_max_load_factor);
if (this->buckets_)
this->max_load_ = this->calculate_max_load();
}
std::size_t min_buckets_for_size(std::size_t size) const
{
BOOST_ASSERT(this->mlf_ >= minimum_max_load_factor);
using namespace std;
// From 6.3.1/13:
// size < mlf_ * count
// => count > size / mlf_
//
// Or from rehash post-condition:
// count > size / mlf_
return policy::new_bucket_count(
boost::unordered::detail::double_to_size(floor(
static_cast<double>(size) /
static_cast<double>(mlf_))) + 1);
}
////////////////////////////////////////////////////////////////////////
// Constructors
table(std::size_t num_buckets,
hasher const& hf,
key_equal const& eq,
node_allocator const& a) :
buckets(a, policy::new_bucket_count(num_buckets)),
functions(hf, eq),
mlf_(1.0f),
max_load_(0)
{}
table(table const& x, node_allocator const& a) :
buckets(a, x.min_buckets_for_size(x.size_)),
functions(x),
mlf_(x.mlf_),
max_load_(0)
{
if(x.size_) {
table_impl::copy_buckets_to(x, *this);
this->max_load_ = calculate_max_load();
}
}
// TODO: Why calculate_max_load?
table(table& x, boost::unordered::detail::move_tag m) :
buckets(x, m),
functions(x),
mlf_(x.mlf_),
max_load_(calculate_max_load())
{}
// TODO: Why not calculate_max_load?
// TODO: Why do I use x's bucket count?
table(table& x, node_allocator const& a,
boost::unordered::detail::move_tag m) :
buckets(a, x.bucket_count_),
functions(x),
mlf_(x.mlf_),
max_load_(x.max_load_)
{
if(a == x.node_alloc()) {
this->buckets::swap(x, false_type());
}
else if(x.size_) {
// Use a temporary table because move_buckets_to leaves the
// source container in a complete mess.
buckets tmp(x, m);
table_impl::move_buckets_to(tmp, *this);
this->max_load_ = calculate_max_load();
}
}
// Iterators
iterator begin() const {
return !this->buckets_ ?
iterator() : this->get_start();
}
// Assignment
void assign(table const& x)
{
assign(x,
boost::unordered::detail::integral_constant<bool,
allocator_traits<node_allocator>::
propagate_on_container_copy_assignment::value>());
}
void assign(table const& x, false_type)
{
table tmp(x, this->node_alloc());
this->swap(tmp, false_type());
}
void assign(table const& x, true_type)
{
table tmp(x, x.node_alloc());
// Need to delete before setting the allocator so that buckets
// aren't deleted with the wrong allocator.
if(this->buckets_) this->delete_buckets();
// TODO: Can allocator assignment throw?
this->allocators_.assign(x.allocators_);
this->swap(tmp, false_type());
}
void move_assign(table& x)
{
move_assign(x,
boost::unordered::detail::integral_constant<bool,
allocator_traits<node_allocator>::
propagate_on_container_move_assignment::value>());
}
void move_assign(table& x, true_type)
{
if(this->buckets_) this->delete_buckets();
this->allocators_.move_assign(x.allocators_);
move_assign_no_alloc(x);
}
void move_assign(table& x, false_type)
{
if(this->node_alloc() == x.node_alloc()) {
if(this->buckets_) this->delete_buckets();
move_assign_no_alloc(x);
}
else {
boost::unordered::detail::set_hash_functions<hasher, key_equal>
new_func_this(*this, x);
if (x.size_) {
buckets b(this->node_alloc(),
x.min_buckets_for_size(x.size_));
buckets tmp(x, move_tag());
table_impl::move_buckets_to(tmp, b);
b.swap(*this);
}
else {
this->clear();
}
this->mlf_ = x.mlf_;
if (this->buckets_) this->max_load_ = calculate_max_load();
new_func_this.commit();
}
}
void move_assign_no_alloc(table& x)
{
boost::unordered::detail::set_hash_functions<hasher, key_equal>
new_func_this(*this, x);
// No throw from here.
this->move_buckets_from(x);
this->mlf_ = x.mlf_;
this->max_load_ = x.max_load_;
new_func_this.commit();
}
////////////////////////////////////////////////////////////////////////
// Swap & Move
void swap(table& x)
{
swap(x,
boost::unordered::detail::integral_constant<bool,
allocator_traits<node_allocator>::
propagate_on_container_swap::value>());
}
// Only swaps the allocators if Propagate::value
template <typename Propagate>
void swap(table& x, Propagate p)
{
boost::unordered::detail::set_hash_functions<hasher, key_equal>
op1(*this, x);
boost::unordered::detail::set_hash_functions<hasher, key_equal>
op2(x, *this);
// I think swap can throw if Propagate::value,
// since the allocators' swap can throw. Not sure though.
this->buckets::swap(x, p);
std::swap(this->mlf_, x.mlf_);
std::swap(this->max_load_, x.max_load_);
op1.commit();
op2.commit();
}
// Swap everything but the allocators, and the functions objects.
void swap_contents(table& x)
{
this->buckets::swap(x, false_type());
std::swap(this->mlf_, x.mlf_);
std::swap(this->max_load_, x.max_load_);
}
// Accessors
key_type const& get_key(value_type const& x) const
{
return extractor::extract(x);
}
std::size_t hash(key_type const& k) const
{
return policy::apply_hash(this->hash_function(), k);
}
// Find Node
template <typename Key, typename Hash, typename Pred>
iterator generic_find_node(
Key const& k,
Hash const& hf,
Pred const& eq) const
{
if (!this->size_) return iterator();
return static_cast<table_impl const*>(this)->
find_node_impl(policy::apply_hash(hf, k), k, eq);
}
iterator find_node(
std::size_t key_hash,
key_type const& k) const
{
if (!this->size_) return iterator();
return static_cast<table_impl const*>(this)->
find_node_impl(key_hash, k, this->key_eq());
}
iterator find_node(key_type const& k) const
{
if (!this->size_) return iterator();
return static_cast<table_impl const*>(this)->
find_node_impl(this->hash(k), k, this->key_eq());
}
iterator find_matching_node(iterator n) const
{
// TODO: Does this apply to C++11?
//
// For some stupid reason, I decided to support equality comparison
// when different hash functions are used. So I can't use the hash
// value from the node here.
return find_node(get_key(*n));
}
// Reserve and rehash
void reserve_for_insert(std::size_t);
void rehash(std::size_t);
void reserve(std::size_t);
};
////////////////////////////////////////////////////////////////////////////
// Reserve & Rehash
// basic exception safety
template <typename Types>
inline void table<Types>::reserve_for_insert(std::size_t size)
{
if (!this->buckets_) {
this->bucket_count_ = (std::max)(this->bucket_count_,
this->min_buckets_for_size(size));
this->create_buckets();
this->max_load_ = this->calculate_max_load();
}
// According to the standard this should be 'size >= max_load_',
// but I think this is better, defect report filed.
else if(size > max_load_) {
std::size_t num_buckets
= this->min_buckets_for_size((std::max)(size,
this->size_ + (this->size_ >> 1)));
if (num_buckets != this->bucket_count_) {
static_cast<table_impl*>(this)->rehash_impl(num_buckets);
this->max_load_ = this->calculate_max_load();
}
}
}
// if hash function throws, basic exception safety
// strong otherwise.
template <typename Types>
inline void table<Types>::rehash(std::size_t min_buckets)
{
using namespace std;
if(!this->size_) {
if(this->buckets_) this->delete_buckets();
this->bucket_count_ = policy::new_bucket_count(min_buckets);
}
else {
min_buckets = policy::new_bucket_count((std::max)(min_buckets,
boost::unordered::detail::double_to_size(floor(
static_cast<double>(this->size_) /
static_cast<double>(mlf_))) + 1));
if(min_buckets != this->bucket_count_) {
static_cast<table_impl*>(this)->rehash_impl(min_buckets);
this->max_load_ = this->calculate_max_load();
}
}
}
template <typename Types>
inline void table<Types>::reserve(std::size_t num_elements)
{
rehash(static_cast<std::size_t>(
std::ceil(static_cast<double>(num_elements) / this->mlf_)));
}
}}}
#endif