YouCompleteMe/cpp/BoostParts/boost/unordered/detail/table.hpp
Strahinja Val Markovic 6fcd1e5e2a Updating to Boost 1.54
2013-08-25 14:35:47 -07:00

862 lines
26 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>
#if defined(BOOST_MSVC)
#pragma warning(push)
#pragma warning(disable:4127) // conditional expression is constant
#endif
#if defined(BOOST_UNORDERED_DEPRECATED_EQUALITY)
#if defined(__EDG__)
#elif defined(_MSC_VER) || defined(__BORLANDC__) || defined(__DMC__)
#pragma message("Warning: BOOST_UNORDERED_DEPRECATED_EQUALITY is no longer supported.")
#elif defined(__GNUC__) || defined(__HP_aCC) || \
defined(__SUNPRO_CC) || defined(__IBMCPP__)
#warning "BOOST_UNORDERED_DEPRECATED_EQUALITY is no longer supported."
#endif
#endif
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 NodeAlloc>
struct copy_nodes
{
typedef boost::unordered::detail::allocator_traits<NodeAlloc>
node_allocator_traits;
node_constructor<NodeAlloc> constructor;
explicit copy_nodes(NodeAlloc& a) : constructor(a) {}
typename node_allocator_traits::pointer create(
typename node_allocator_traits::value_type::value_type const& v)
{
constructor.construct_with_value2(v);
return constructor.release();
}
};
template <typename NodeAlloc>
struct move_nodes
{
typedef boost::unordered::detail::allocator_traits<NodeAlloc>
node_allocator_traits;
node_constructor<NodeAlloc> constructor;
explicit move_nodes(NodeAlloc& a) : constructor(a) {}
typename node_allocator_traits::pointer create(
typename node_allocator_traits::value_type::value_type& v)
{
constructor.construct_with_value2(boost::move(v));
return constructor.release();
}
};
template <typename Buckets>
struct assign_nodes
{
node_holder<typename Buckets::node_allocator> holder;
explicit assign_nodes(Buckets& b) : holder(b) {}
typename Buckets::node_pointer create(
typename Buckets::value_type const& v)
{
return holder.copy_of(v);
}
};
template <typename Buckets>
struct move_assign_nodes
{
node_holder<typename Buckets::node_allocator> holder;
explicit move_assign_nodes(Buckets& b) : holder(b) {}
typename Buckets::node_pointer create(
typename Buckets::value_type& v)
{
return holder.move_copy_of(v);
}
};
template <typename Types>
struct table :
boost::unordered::detail::functions<
typename Types::hasher,
typename Types::key_equal>
{
private:
table(table const&);
table& operator=(table const&);
public:
typedef typename Types::node node;
typedef typename Types::bucket bucket;
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 typename functions::set_hash_functions set_hash_functions;
typedef typename Types::allocator allocator;
typedef typename boost::unordered::detail::
rebind_wrap<allocator, node>::type node_allocator;
typedef typename boost::unordered::detail::
rebind_wrap<allocator, bucket>::type bucket_allocator;
typedef boost::unordered::detail::allocator_traits<node_allocator>
node_allocator_traits;
typedef boost::unordered::detail::allocator_traits<bucket_allocator>
bucket_allocator_traits;
typedef typename node_allocator_traits::pointer
node_pointer;
typedef typename node_allocator_traits::const_pointer
const_node_pointer;
typedef typename bucket_allocator_traits::pointer
bucket_pointer;
typedef boost::unordered::detail::node_constructor<node_allocator>
node_constructor;
typedef boost::unordered::iterator_detail::
iterator<node> iterator;
typedef boost::unordered::iterator_detail::
c_iterator<node, const_node_pointer> c_iterator;
typedef boost::unordered::iterator_detail::
l_iterator<node, policy> l_iterator;
typedef boost::unordered::iterator_detail::
cl_iterator<node, const_node_pointer, policy> cl_iterator;
////////////////////////////////////////////////////////////////////////
// Members
boost::unordered::detail::compressed<bucket_allocator, node_allocator>
allocators_;
std::size_t bucket_count_;
std::size_t size_;
float mlf_;
std::size_t max_load_;
bucket_pointer buckets_;
////////////////////////////////////////////////////////////////////////
// Data access
bucket_allocator const& bucket_alloc() const
{
return allocators_.first();
}
node_allocator const& node_alloc() const
{
return allocators_.second();
}
bucket_allocator& bucket_alloc()
{
return allocators_.first();
}
node_allocator& node_alloc()
{
return allocators_.second();
}
std::size_t max_bucket_count() const
{
// -1 to account for the start bucket.
return policy::prev_bucket_count(
bucket_allocator_traits::max_size(bucket_alloc()) - 1);
}
bucket_pointer get_bucket(std::size_t bucket_index) const
{
BOOST_ASSERT(buckets_);
return buckets_ + static_cast<std::ptrdiff_t>(bucket_index);
}
link_pointer get_previous_start() const
{
return get_bucket(bucket_count_)->first_from_start();
}
link_pointer get_previous_start(std::size_t bucket_index) const
{
return get_bucket(bucket_index)->next_;
}
iterator begin() const
{
return size_ ? iterator(get_previous_start()->next_) : iterator();
}
iterator begin(std::size_t bucket_index) const
{
if (!size_) return iterator();
link_pointer prev = get_previous_start(bucket_index);
return prev ? iterator(prev->next_) : iterator();
}
std::size_t hash_to_bucket(std::size_t hash) const
{
return policy::to_bucket(bucket_count_, hash);
}
float load_factor() const
{
BOOST_ASSERT(bucket_count_ != 0);
return static_cast<float>(size_)
/ static_cast<float>(bucket_count_);
}
std::size_t bucket_size(std::size_t index) const
{
iterator it = begin(index);
if (!it.node_) return 0;
std::size_t count = 0;
while(it.node_ && hash_to_bucket(it.node_->hash_) == index)
{
++count;
++it;
}
return count;
}
////////////////////////////////////////////////////////////////////////
// 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>(mlf_) *
static_cast<double>(max_bucket_count())
)) - 1;
}
void recalculate_max_load()
{
using namespace std;
// From 6.3.1/13:
// Only resize when size >= mlf_ * count
max_load_ = buckets_ ? boost::unordered::detail::double_to_size(ceil(
static_cast<double>(mlf_) *
static_cast<double>(bucket_count_)
)) : 0;
}
void max_load_factor(float z)
{
BOOST_ASSERT(z > 0);
mlf_ = (std::max)(z, minimum_max_load_factor);
recalculate_max_load();
}
std::size_t min_buckets_for_size(std::size_t size) const
{
BOOST_ASSERT(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) :
functions(hf, eq),
allocators_(a,a),
bucket_count_(policy::new_bucket_count(num_buckets)),
size_(0),
mlf_(1.0f),
max_load_(0),
buckets_()
{}
table(table const& x, node_allocator const& a) :
functions(x),
allocators_(a,a),
bucket_count_(x.min_buckets_for_size(x.size_)),
size_(0),
mlf_(x.mlf_),
max_load_(0),
buckets_()
{}
table(table& x, boost::unordered::detail::move_tag m) :
functions(x, m),
allocators_(x.allocators_, m),
bucket_count_(x.bucket_count_),
size_(x.size_),
mlf_(x.mlf_),
max_load_(x.max_load_),
buckets_(x.buckets_)
{
x.buckets_ = bucket_pointer();
x.size_ = 0;
x.max_load_ = 0;
}
table(table& x, node_allocator const& a,
boost::unordered::detail::move_tag m) :
functions(x, m),
allocators_(a, a),
bucket_count_(x.bucket_count_),
size_(0),
mlf_(x.mlf_),
max_load_(x.max_load_),
buckets_()
{}
////////////////////////////////////////////////////////////////////////
// Initialisation.
void init(table const& x)
{
if (x.size_) {
create_buckets(bucket_count_);
copy_nodes<node_allocator> copy(node_alloc());
table_impl::fill_buckets(x.begin(), *this, copy);
}
}
void move_init(table& x)
{
if(node_alloc() == x.node_alloc()) {
move_buckets_from(x);
}
else if(x.size_) {
// TODO: Could pick new bucket size?
create_buckets(bucket_count_);
move_nodes<node_allocator> move(node_alloc());
node_holder<node_allocator> nodes(x);
table_impl::fill_buckets(nodes.begin(), *this, move);
}
}
////////////////////////////////////////////////////////////////////////
// Create buckets
void create_buckets(std::size_t new_count)
{
boost::unordered::detail::array_constructor<bucket_allocator>
constructor(bucket_alloc());
// Creates an extra bucket to act as the start node.
constructor.construct(bucket(), new_count + 1);
if (buckets_)
{
// Copy the nodes to the new buckets, including the dummy
// node if there is one.
(constructor.get() +
static_cast<std::ptrdiff_t>(new_count))->next_ =
(buckets_ + static_cast<std::ptrdiff_t>(
bucket_count_))->next_;
destroy_buckets();
}
else if (bucket::extra_node)
{
node_constructor a(node_alloc());
a.construct();
(constructor.get() +
static_cast<std::ptrdiff_t>(new_count))->next_ =
a.release();
}
bucket_count_ = new_count;
buckets_ = constructor.release();
recalculate_max_load();
}
////////////////////////////////////////////////////////////////////////
// Swap and Move
void swap_allocators(table& other, false_type)
{
// According to 23.2.1.8, if propagate_on_container_swap is
// false the behaviour is undefined unless the allocators
// are equal.
BOOST_ASSERT(node_alloc() == other.node_alloc());
}
void swap_allocators(table& other, true_type)
{
allocators_.swap(other.allocators_);
}
// Only swaps the allocators if propagate_on_container_swap
void swap(table& x)
{
set_hash_functions op1(*this, x);
set_hash_functions op2(x, *this);
// I think swap can throw if Propagate::value,
// since the allocators' swap can throw. Not sure though.
swap_allocators(x,
boost::unordered::detail::integral_constant<bool,
allocator_traits<node_allocator>::
propagate_on_container_swap::value>());
boost::swap(buckets_, x.buckets_);
boost::swap(bucket_count_, x.bucket_count_);
boost::swap(size_, x.size_);
std::swap(mlf_, x.mlf_);
std::swap(max_load_, x.max_load_);
op1.commit();
op2.commit();
}
void move_buckets_from(table& other)
{
BOOST_ASSERT(node_alloc() == other.node_alloc());
BOOST_ASSERT(!buckets_);
buckets_ = other.buckets_;
bucket_count_ = other.bucket_count_;
size_ = other.size_;
other.buckets_ = bucket_pointer();
other.size_ = 0;
other.max_load_ = 0;
}
////////////////////////////////////////////////////////////////////////
// Delete/destruct
~table()
{
delete_buckets();
}
void delete_node(link_pointer prev)
{
node_pointer n = static_cast<node_pointer>(prev->next_);
prev->next_ = n->next_;
boost::unordered::detail::destroy_value_impl(node_alloc(),
n->value_ptr());
node_allocator_traits::destroy(node_alloc(),
boost::addressof(*n));
node_allocator_traits::deallocate(node_alloc(), n, 1);
--size_;
}
std::size_t delete_nodes(link_pointer prev, link_pointer end)
{
BOOST_ASSERT(prev->next_ != end);
std::size_t count = 0;
do {
delete_node(prev);
++count;
} while (prev->next_ != end);
return count;
}
void delete_buckets()
{
if(buckets_) {
if (size_) delete_nodes(get_previous_start(), link_pointer());
if (bucket::extra_node) {
node_pointer n = static_cast<node_pointer>(
get_bucket(bucket_count_)->next_);
node_allocator_traits::destroy(node_alloc(),
boost::addressof(*n));
node_allocator_traits::deallocate(node_alloc(), n, 1);
}
destroy_buckets();
buckets_ = bucket_pointer();
max_load_ = 0;
}
BOOST_ASSERT(!size_);
}
void clear()
{
if (!size_) return;
delete_nodes(get_previous_start(), link_pointer());
clear_buckets();
BOOST_ASSERT(!size_);
}
void clear_buckets()
{
bucket_pointer end = get_bucket(bucket_count_);
for(bucket_pointer it = buckets_; it != end; ++it)
{
it->next_ = node_pointer();
}
}
void destroy_buckets()
{
bucket_pointer end = get_bucket(bucket_count_ + 1);
for(bucket_pointer it = buckets_; it != end; ++it)
{
bucket_allocator_traits::destroy(bucket_alloc(),
boost::addressof(*it));
}
bucket_allocator_traits::deallocate(bucket_alloc(),
buckets_, bucket_count_ + 1);
}
////////////////////////////////////////////////////////////////////////
// Fix buckets after delete
//
std::size_t fix_bucket(std::size_t bucket_index, link_pointer prev)
{
link_pointer end = prev->next_;
std::size_t bucket_index2 = bucket_index;
if (end)
{
bucket_index2 = hash_to_bucket(
static_cast<node_pointer>(end)->hash_);
// If begin and end are in the same bucket, then
// there's nothing to do.
if (bucket_index == bucket_index2) return bucket_index2;
// Update the bucket containing end.
get_bucket(bucket_index2)->next_ = prev;
}
// Check if this bucket is now empty.
bucket_pointer this_bucket = get_bucket(bucket_index);
if (this_bucket->next_ == prev)
this_bucket->next_ = link_pointer();
return bucket_index2;
}
////////////////////////////////////////////////////////////////////////
// Assignment
void assign(table const& x)
{
if (this != boost::addressof(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)
{
// Strong exception safety.
set_hash_functions new_func_this(*this, x);
new_func_this.commit();
mlf_ = x.mlf_;
recalculate_max_load();
if (!size_ && !x.size_) return;
if (x.size_ >= max_load_) {
create_buckets(min_buckets_for_size(x.size_));
}
else {
clear_buckets();
}
// assign_nodes takes ownership of the container's elements,
// assigning to them if possible, and deleting any that are
// left over.
assign_nodes<table> assign(*this);
table_impl::fill_buckets(x.begin(), *this, assign);
}
void assign(table const& x, true_type)
{
if (node_alloc() == x.node_alloc()) {
allocators_.assign(x.allocators_);
assign(x, false_type());
}
else {
set_hash_functions new_func_this(*this, x);
// Delete everything with current allocators before assigning
// the new ones.
delete_buckets();
allocators_.assign(x.allocators_);
// Copy over other data, all no throw.
new_func_this.commit();
mlf_ = x.mlf_;
bucket_count_ = min_buckets_for_size(x.size_);
max_load_ = 0;
// Finally copy the elements.
if (x.size_) {
create_buckets(bucket_count_);
copy_nodes<node_allocator> copy(node_alloc());
table_impl::fill_buckets(x.begin(), *this, copy);
}
}
}
void move_assign(table& x)
{
if (this != boost::addressof(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)
{
delete_buckets();
allocators_.move_assign(x.allocators_);
move_assign_no_alloc(x);
}
void move_assign(table& x, false_type)
{
if (node_alloc() == x.node_alloc()) {
delete_buckets();
move_assign_no_alloc(x);
}
else {
set_hash_functions new_func_this(*this, x);
new_func_this.commit();
mlf_ = x.mlf_;
recalculate_max_load();
if (!size_ && !x.size_) return;
if (x.size_ >= max_load_) {
create_buckets(min_buckets_for_size(x.size_));
}
else {
clear_buckets();
}
// move_assign_nodes takes ownership of the container's
// elements, assigning to them if possible, and deleting
// any that are left over.
move_assign_nodes<table> assign(*this);
node_holder<node_allocator> nodes(x);
table_impl::fill_buckets(nodes.begin(), *this, assign);
}
}
void move_assign_no_alloc(table& x)
{
set_hash_functions new_func_this(*this, x);
// No throw from here.
mlf_ = x.mlf_;
max_load_ = x.max_load_;
move_buckets_from(x);
new_func_this.commit();
}
// 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
{
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
{
return static_cast<table_impl const*>(this)->
find_node_impl(key_hash, k, this->key_eq());
}
iterator find_node(key_type const& k) const
{
return static_cast<table_impl const*>(this)->
find_node_impl(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 (!buckets_) {
create_buckets((std::max)(bucket_count_,
min_buckets_for_size(size)));
}
// 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
= min_buckets_for_size((std::max)(size,
size_ + (size_ >> 1)));
if (num_buckets != bucket_count_)
static_cast<table_impl*>(this)->rehash_impl(num_buckets);
}
}
// 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(!size_) {
delete_buckets();
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>(size_) /
static_cast<double>(mlf_))) + 1));
if(min_buckets != bucket_count_)
static_cast<table_impl*>(this)->rehash_impl(min_buckets);
}
}
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) / mlf_)));
}
}}}
#if defined(BOOST_MSVC)
#pragma warning(pop)
#endif
#endif