gcc/libstdc++-v3/include/bits/hashtable.h
François Dumont da29608a7a re PR libstdc++/41975 ([C++0x] [DR579] unordered_set::erase performs worse when nearly empty)
2011-11-23  François Dumont <fdumont@gcc.gnu.org>

	PR libstdc++/41975
	* include/bits/hashtable.h (_Hashtable<>): Major data model
	modification to limit performance impact of empty buckets in
	erase(iterator) implementation.
	* include/bits/hashtable_policy.h (_Hashtable_iterator,
	_Hashtable_const_iterator): Remove not used anymore.
	* include/bits/hashtable_policy.h (_Prime_rehash_policy): Remove
	_M_grow_factor, just use natural evolution of prime numbers. Add
	_M_prev_size to know when the number of buckets can be reduced.
	* include/bits/unordered_set.h (__unordered_set<>,
	__unordered_multiset<>), unordered_map.h (__unordered_map<>,
	__unordered_multimap<>): Change default value of cache hash code
	template parameter, false for integral types with noexcept hash
	functor, true otherwise.
	* include/debug/unordered_map, unordered_set: Adapt transformation
	from iterator/const_iterator to respectively
	local_iterator/const_local_iterator.
	* testsuite/performance/23_containers/copy_construct/unordered_set.cc:
	New.
	* testsuite/23_containers/unordered_set/instantiation_neg.cc: New.
	* testsuite/23_containers/unordered_set/hash_policy/rehash.cc: New.
	* testsuite/23_containers/unordered_multiset/cons/copy.cc: New.
	* testsuite/23_containers/unordered_multiset/erase/1.cc,
	24061-multiset.cc: Add checks on the number of bucket elements.
	* testsuite/23_containers/unordered_multiset/insert/multiset_range.cc,
	multiset_single.cc, multiset_single_move.cc: Likewise.

From-SVN: r181677
2011-11-23 20:30:18 +00:00

1620 lines
57 KiB
C++

// hashtable.h header -*- C++ -*-
// Copyright (C) 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.
// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
// <http://www.gnu.org/licenses/>.
/** @file bits/hashtable.h
* This is an internal header file, included by other library headers.
* Do not attempt to use it directly. @headername{unordered_map, unordered_set}
*/
#ifndef _HASHTABLE_H
#define _HASHTABLE_H 1
#pragma GCC system_header
#include <bits/hashtable_policy.h>
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
// Class template _Hashtable, class definition.
// Meaning of class template _Hashtable's template parameters
// _Key and _Value: arbitrary CopyConstructible types.
// _Allocator: an allocator type ([lib.allocator.requirements]) whose
// value type is Value. As a conforming extension, we allow for
// value type != Value.
// _ExtractKey: function object that takes an object of type Value
// and returns a value of type _Key.
// _Equal: function object that takes two objects of type k and returns
// a bool-like value that is true if the two objects are considered equal.
// _H1: the hash function. A unary function object with argument type
// Key and result type size_t. Return values should be distributed
// over the entire range [0, numeric_limits<size_t>:::max()].
// _H2: the range-hashing function (in the terminology of Tavori and
// Dreizin). A binary function object whose argument types and result
// type are all size_t. Given arguments r and N, the return value is
// in the range [0, N).
// _Hash: the ranged hash function (Tavori and Dreizin). A binary function
// whose argument types are _Key and size_t and whose result type is
// size_t. Given arguments k and N, the return value is in the range
// [0, N). Default: hash(k, N) = h2(h1(k), N). If _Hash is anything other
// than the default, _H1 and _H2 are ignored.
// _RehashPolicy: Policy class with three members, all of which govern
// the bucket count. _M_next_bkt(n) returns a bucket count no smaller
// than n. _M_bkt_for_elements(n) returns a bucket count appropriate
// for an element count of n. _M_need_rehash(n_bkt, n_elt, n_ins)
// determines whether, if the current bucket count is n_bkt and the
// current element count is n_elt, we need to increase the bucket
// count. If so, returns make_pair(true, n), where n is the new
// bucket count. If not, returns make_pair(false, <anything>).
// __cache_hash_code: bool. true if we store the value of the hash
// function along with the value. This is a time-space tradeoff.
// Storing it may improve lookup speed by reducing the number of times
// we need to call the Equal function.
// __constant_iterators: bool. true if iterator and const_iterator are
// both constant iterator types. This is true for unordered_set and
// unordered_multiset, false for unordered_map and unordered_multimap.
// __unique_keys: bool. true if the return value of _Hashtable::count(k)
// is always at most one, false if it may be an arbitrary number. This
// true for unordered_set and unordered_map, false for unordered_multiset
// and unordered_multimap.
/**
* Here's _Hashtable data structure, each _Hashtable has:
* - _Bucket[] _M_buckets
* - size_type _M_bucket_count
* - size_type _M_begin_bucket_index
* - size_type _M_element_count
*
* with _Bucket being _Node* and _Node:
* - _Node* _M_next
* - Tp _M_value
* - size_t _M_code if cache_hash_code is true
*
* In terms of Standard containers the hastable is like the aggregation of:
* - std::forward_list<_Node> containing the elements
* - std::vector<std::forward_list<_Node>::iterator> representing the buckets
*
* The first non-empty bucket with index _M_begin_bucket_index contains the
* first container node which is also the first bucket node whereas other
* non-empty buckets contain the node before the first bucket node. This is so
* to implement something like a std::forward_list::erase_after on container
* erase calls.
*
* Access to the bucket last element require a check on the hash code to see
* if the node is still in the bucket. Such a design impose a quite efficient
* hash functor and is one of the reasons it is highly advise to set
* __cache_hash_code to true.
*
* The container iterators are simply built from nodes. This way incrementing
* the iterator is perfectly efficient no matter how many empty buckets there
* are in the container.
*
* On insert we compute element hash code and thanks to it find the bucket
* index. If the element is the first one in the bucket we must find the
* previous non-empty bucket where the previous node rely. To keep this loop
* minimal it is important that the number of bucket is not too high compared
* to the number of elements. So the hash policy must be carefully design so
* that it computes a bucket count large enough to respect the user defined
* load factor but also not too large to limit impact on the insert operation.
*
* On erase, the simple iterator design impose to use the hash functor to get
* the index of the bucket to update. For this reason, when __cache_hash_code
* is set to false, there is a static assertion that the hash functor cannot
* throw.
*
* _M_begin_bucket_index is used to offer contant time access to the container
* begin iterator.
*/
template<typename _Key, typename _Value, typename _Allocator,
typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash,
typename _RehashPolicy,
bool __cache_hash_code,
bool __constant_iterators,
bool __unique_keys>
class _Hashtable
: public __detail::_Rehash_base<_RehashPolicy,
_Hashtable<_Key, _Value, _Allocator,
_ExtractKey,
_Equal, _H1, _H2, _Hash,
_RehashPolicy,
__cache_hash_code,
__constant_iterators,
__unique_keys> >,
public __detail::_Hash_code_base<_Key, _Value, _ExtractKey, _Equal,
_H1, _H2, _Hash, __cache_hash_code>,
public __detail::_Map_base<_Key, _Value, _ExtractKey, __unique_keys,
_Hashtable<_Key, _Value, _Allocator,
_ExtractKey,
_Equal, _H1, _H2, _Hash,
_RehashPolicy,
__cache_hash_code,
__constant_iterators,
__unique_keys> >,
public __detail::_Equality_base<_ExtractKey, __unique_keys,
_Hashtable<_Key, _Value, _Allocator,
_ExtractKey,
_Equal, _H1, _H2, _Hash,
_RehashPolicy,
__cache_hash_code,
__constant_iterators,
__unique_keys> >
{
static_assert(__or_<integral_constant<bool, __cache_hash_code>,
__detail::__is_noexcept_hash<_Key, _H1>>::value,
"Cache the hash code or qualify your hash functor with noexcept");
public:
typedef _Allocator allocator_type;
typedef _Value value_type;
typedef _Key key_type;
typedef _Equal key_equal;
// mapped_type, if present, comes from _Map_base.
// hasher, if present, comes from _Hash_code_base.
typedef typename _Allocator::pointer pointer;
typedef typename _Allocator::const_pointer const_pointer;
typedef typename _Allocator::reference reference;
typedef typename _Allocator::const_reference const_reference;
typedef std::size_t size_type;
typedef std::ptrdiff_t difference_type;
typedef __detail::_Node_iterator<value_type, __constant_iterators,
__cache_hash_code>
local_iterator;
typedef __detail::_Node_const_iterator<value_type,
__constant_iterators,
__cache_hash_code>
const_local_iterator;
typedef local_iterator iterator;
typedef const_local_iterator const_iterator;
template<typename _Key2, typename _Value2, typename _Ex2, bool __unique2,
typename _Hashtable2>
friend struct __detail::_Map_base;
private:
typedef typename _RehashPolicy::_State _RehashPolicyState;
typedef __detail::_Hash_node<_Value, __cache_hash_code> _Node;
typedef typename _Allocator::template rebind<_Node>::other
_Node_allocator_type;
typedef _Node* _Bucket;
//typedef __detail::_Bucket<_Value, __cache_hash_code> _Bucket;
typedef typename _Allocator::template rebind<_Bucket>::other
_Bucket_allocator_type;
typedef typename _Allocator::template rebind<_Value>::other
_Value_allocator_type;
_Node_allocator_type _M_node_allocator;
_Bucket* _M_buckets;
size_type _M_bucket_count;
size_type _M_begin_bucket_index; // First non-empty bucket.
size_type _M_element_count;
_RehashPolicy _M_rehash_policy;
template<typename... _Args>
_Node*
_M_allocate_node(_Args&&... __args);
void
_M_deallocate_node(_Node* __n);
// Deallocate all nodes contained in the bucket array, buckets' nodes
// are not linked to each other
void
_M_deallocate_nodes(_Bucket*, size_type);
// Deallocate the linked list of nodes pointed to by __n
void
_M_deallocate_nodes(_Node* __n);
_Bucket*
_M_allocate_buckets(size_type __n);
void
_M_deallocate_buckets(_Bucket*, size_type __n);
// Gets bucket begin dealing with the difference between first non-empty
// bucket containing the first container node and the other non-empty
// buckets containing the node before the one belonging to the bucket.
_Node*
_M_bucket_begin(size_type __bkt) const;
// Gets the bucket last node if any
_Node*
_M_bucket_end(size_type __bkt) const;
// Gets the bucket node after the last if any
_Node*
_M_bucket_past_the_end(size_type __bkt) const
{
_Node* __end = _M_bucket_end(__bkt);
return __end ? __end->_M_next : nullptr;
}
public:
// Constructor, destructor, assignment, swap
_Hashtable(size_type __bucket_hint,
const _H1&, const _H2&, const _Hash&,
const _Equal&, const _ExtractKey&,
const allocator_type&);
template<typename _InputIterator>
_Hashtable(_InputIterator __first, _InputIterator __last,
size_type __bucket_hint,
const _H1&, const _H2&, const _Hash&,
const _Equal&, const _ExtractKey&,
const allocator_type&);
_Hashtable(const _Hashtable&);
_Hashtable(_Hashtable&&);
_Hashtable&
operator=(const _Hashtable& __ht)
{
_Hashtable __tmp(__ht);
this->swap(__tmp);
return *this;
}
_Hashtable&
operator=(_Hashtable&& __ht)
{
// NB: DR 1204.
// NB: DR 675.
this->clear();
this->swap(__ht);
return *this;
}
~_Hashtable() noexcept;
void swap(_Hashtable&);
// Basic container operations
iterator
begin() noexcept
{ return iterator(_M_buckets[_M_begin_bucket_index]); }
const_iterator
begin() const noexcept
{ return const_iterator(_M_buckets[_M_begin_bucket_index]); }
iterator
end() noexcept
{ return iterator(nullptr); }
const_iterator
end() const noexcept
{ return const_iterator(nullptr); }
const_iterator
cbegin() const noexcept
{ return const_iterator(_M_buckets[_M_begin_bucket_index]); }
const_iterator
cend() const noexcept
{ return const_iterator(nullptr); }
size_type
size() const noexcept
{ return _M_element_count; }
bool
empty() const noexcept
{ return size() == 0; }
allocator_type
get_allocator() const noexcept
{ return allocator_type(_M_node_allocator); }
size_type
max_size() const noexcept
{ return _M_node_allocator.max_size(); }
// Observers
key_equal
key_eq() const
{ return this->_M_eq; }
// hash_function, if present, comes from _Hash_code_base.
// Bucket operations
size_type
bucket_count() const noexcept
{ return _M_bucket_count; }
size_type
max_bucket_count() const noexcept
{ return max_size(); }
size_type
bucket_size(size_type __n) const
{ return std::distance(begin(__n), end(__n)); }
size_type
bucket(const key_type& __k) const
{
return this->_M_bucket_index(__k, this->_M_hash_code(__k),
bucket_count());
}
local_iterator
begin(size_type __n)
{ return local_iterator(_M_bucket_begin(__n)); }
local_iterator
end(size_type __n)
{ return local_iterator(_M_bucket_past_the_end(__n)); }
const_local_iterator
begin(size_type __n) const
{ return const_local_iterator(_M_bucket_begin(__n)); }
const_local_iterator
end(size_type __n) const
{ return const_local_iterator(_M_bucket_past_the_end(__n)); }
// DR 691.
const_local_iterator
cbegin(size_type __n) const
{ return const_local_iterator(_M_bucket_begin(__n)); }
const_local_iterator
cend(size_type __n) const
{ return const_local_iterator(_M_bucket_past_the_end(__n)); }
float
load_factor() const noexcept
{
return static_cast<float>(size()) / static_cast<float>(bucket_count());
}
// max_load_factor, if present, comes from _Rehash_base.
// Generalization of max_load_factor. Extension, not found in TR1. Only
// useful if _RehashPolicy is something other than the default.
const _RehashPolicy&
__rehash_policy() const
{ return _M_rehash_policy; }
void
__rehash_policy(const _RehashPolicy&);
// Lookup.
iterator
find(const key_type& __k);
const_iterator
find(const key_type& __k) const;
size_type
count(const key_type& __k) const;
std::pair<iterator, iterator>
equal_range(const key_type& __k);
std::pair<const_iterator, const_iterator>
equal_range(const key_type& __k) const;
private:
// Find and insert helper functions and types
_Node*
_M_find_node(size_type, const key_type&,
typename _Hashtable::_Hash_code_type) const;
// Insert a node in an empty bucket
void
_M_insert_bucket_begin(size_type, _Node*);
// Insert a node after an other one in a non-empty bucket
void
_M_insert_after(size_type, _Node*, _Node*);
// Remove the bucket first node
void
_M_remove_bucket_begin(size_type __bkt, _Node* __next_n,
size_type __next_bkt);
// Get the node before __n in the bucket __bkt
_Node*
_M_get_previous_node(size_type __bkt, _Node* __n);
template<typename _Arg>
iterator
_M_insert_bucket(_Arg&&, size_type,
typename _Hashtable::_Hash_code_type);
typedef typename std::conditional<__unique_keys,
std::pair<iterator, bool>,
iterator>::type
_Insert_Return_Type;
typedef typename std::conditional<__unique_keys,
std::_Select1st<_Insert_Return_Type>,
std::_Identity<_Insert_Return_Type>
>::type
_Insert_Conv_Type;
protected:
template<typename _Arg>
std::pair<iterator, bool>
_M_insert(_Arg&&, std::true_type);
template<typename _Arg>
iterator
_M_insert(_Arg&&, std::false_type);
public:
// Insert and erase
_Insert_Return_Type
insert(const value_type& __v)
{ return _M_insert(__v, integral_constant<bool, __unique_keys>()); }
iterator
insert(const_iterator, const value_type& __v)
{ return _Insert_Conv_Type()(insert(__v)); }
template<typename _Pair, typename = typename
std::enable_if<__and_<integral_constant<bool, !__constant_iterators>,
std::is_convertible<_Pair,
value_type>>::value>::type>
_Insert_Return_Type
insert(_Pair&& __v)
{ return _M_insert(std::forward<_Pair>(__v),
integral_constant<bool, __unique_keys>()); }
template<typename _Pair, typename = typename
std::enable_if<__and_<integral_constant<bool, !__constant_iterators>,
std::is_convertible<_Pair,
value_type>>::value>::type>
iterator
insert(const_iterator, _Pair&& __v)
{ return _Insert_Conv_Type()(insert(std::forward<_Pair>(__v))); }
template<typename _InputIterator>
void
insert(_InputIterator __first, _InputIterator __last);
void
insert(initializer_list<value_type> __l)
{ this->insert(__l.begin(), __l.end()); }
iterator
erase(const_iterator);
// LWG 2059.
iterator
erase(iterator __it)
{ return erase(const_iterator(__it)); }
size_type
erase(const key_type&);
iterator
erase(const_iterator, const_iterator);
void
clear() noexcept;
// Set number of buckets to be appropriate for container of n element.
void rehash(size_type __n);
// DR 1189.
// reserve, if present, comes from _Rehash_base.
private:
// Unconditionally change size of bucket array to n, restore hash policy
// state to __state on exception.
void _M_rehash(size_type __n, const _RehashPolicyState& __state);
};
// Definitions of class template _Hashtable's out-of-line member functions.
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
template<typename... _Args>
typename _Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy,
__chc, __cit, __uk>::_Node*
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_M_allocate_node(_Args&&... __args)
{
_Node* __n = _M_node_allocator.allocate(1);
__try
{
_M_node_allocator.construct(__n, std::forward<_Args>(__args)...);
return __n;
}
__catch(...)
{
_M_node_allocator.deallocate(__n, 1);
__throw_exception_again;
}
}
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
void
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_M_deallocate_node(_Node* __n)
{
_M_node_allocator.destroy(__n);
_M_node_allocator.deallocate(__n, 1);
}
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
void
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_M_deallocate_nodes(_Bucket* __buckets, size_type __n)
{
for (size_type __i = 0; __i != __n; ++__i)
_M_deallocate_nodes(__buckets[__i]);
}
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
void
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_M_deallocate_nodes(_Node* __n)
{
while (__n)
{
_Node* __tmp = __n;
__n = __n->_M_next;
_M_deallocate_node(__tmp);
}
}
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
typename _Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy,
__chc, __cit, __uk>::_Bucket*
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_M_allocate_buckets(size_type __n)
{
_Bucket_allocator_type __alloc(_M_node_allocator);
// We allocate one extra bucket to have _M_begin_bucket_index
// point to it as long as container is empty
_Bucket* __p = __alloc.allocate(__n + 1);
__builtin_memset(__p, 0, (__n + 1) * sizeof(_Bucket));
return __p;
}
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
void
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_M_deallocate_buckets(_Bucket* __p, size_type __n)
{
_Bucket_allocator_type __alloc(_M_node_allocator);
__alloc.deallocate(__p, __n + 1);
}
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
typename _Hashtable<_Key, _Value, _Allocator, _ExtractKey,
_Equal, _H1, _H2, _Hash, _RehashPolicy,
__chc, __cit, __uk>::_Node*
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_M_bucket_begin(size_type __bkt) const
{
if (__bkt == _M_begin_bucket_index)
return _M_buckets[__bkt];
_Node* __n = _M_buckets[__bkt];
return __n ? __n->_M_next : nullptr;
}
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
typename _Hashtable<_Key, _Value, _Allocator, _ExtractKey,
_Equal, _H1, _H2, _Hash, _RehashPolicy,
__chc, __cit, __uk>::_Node*
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_M_bucket_end(size_type __bkt) const
{
_Node* __n = _M_bucket_begin(__bkt);
if (__n)
for (;; __n = __n->_M_next)
if (!__n->_M_next
|| this->_M_bucket_index(__n->_M_next, _M_bucket_count)
!= __bkt)
break;
return __n;
}
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_Hashtable(size_type __bucket_hint,
const _H1& __h1, const _H2& __h2, const _Hash& __h,
const _Equal& __eq, const _ExtractKey& __exk,
const allocator_type& __a)
: __detail::_Rehash_base<_RehashPolicy, _Hashtable>(),
__detail::_Hash_code_base<_Key, _Value, _ExtractKey, _Equal,
_H1, _H2, _Hash, __chc>(__exk, __eq,
__h1, __h2, __h),
__detail::_Map_base<_Key, _Value, _ExtractKey, __uk, _Hashtable>(),
_M_node_allocator(__a),
_M_bucket_count(0),
_M_element_count(0),
_M_rehash_policy()
{
_M_bucket_count = _M_rehash_policy._M_next_bkt(__bucket_hint);
// We don't want the rehash policy to ask for the hashtable to shrink
// on the first insertion so we need to reset its previous resize level.
_M_rehash_policy._M_prev_resize = 0;
_M_buckets = _M_allocate_buckets(_M_bucket_count);
_M_begin_bucket_index = _M_bucket_count;
}
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
template<typename _InputIterator>
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_Hashtable(_InputIterator __f, _InputIterator __l,
size_type __bucket_hint,
const _H1& __h1, const _H2& __h2, const _Hash& __h,
const _Equal& __eq, const _ExtractKey& __exk,
const allocator_type& __a)
: __detail::_Rehash_base<_RehashPolicy, _Hashtable>(),
__detail::_Hash_code_base<_Key, _Value, _ExtractKey, _Equal,
_H1, _H2, _Hash, __chc>(__exk, __eq,
__h1, __h2, __h),
__detail::_Map_base<_Key, _Value, _ExtractKey, __uk, _Hashtable>(),
_M_node_allocator(__a),
_M_bucket_count(0),
_M_element_count(0),
_M_rehash_policy()
{
_M_bucket_count = std::max(_M_rehash_policy._M_next_bkt(__bucket_hint),
_M_rehash_policy.
_M_bkt_for_elements(__detail::
__distance_fw(__f,
__l)));
// We don't want the rehash policy to ask for the hashtable to shrink
// on the first insertion so we need to reset its previous resize
// level.
_M_rehash_policy._M_prev_resize = 0;
_M_buckets = _M_allocate_buckets(_M_bucket_count);
_M_begin_bucket_index = _M_bucket_count;
__try
{
for (; __f != __l; ++__f)
this->insert(*__f);
}
__catch(...)
{
clear();
_M_deallocate_buckets(_M_buckets, _M_bucket_count);
__throw_exception_again;
}
}
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_Hashtable(const _Hashtable& __ht)
: __detail::_Rehash_base<_RehashPolicy, _Hashtable>(__ht),
__detail::_Hash_code_base<_Key, _Value, _ExtractKey, _Equal,
_H1, _H2, _Hash, __chc>(__ht),
__detail::_Map_base<_Key, _Value, _ExtractKey, __uk, _Hashtable>(__ht),
_M_node_allocator(__ht._M_node_allocator),
_M_bucket_count(__ht._M_bucket_count),
_M_begin_bucket_index(__ht._M_begin_bucket_index),
_M_element_count(__ht._M_element_count),
_M_rehash_policy(__ht._M_rehash_policy)
{
_M_buckets = _M_allocate_buckets(_M_bucket_count);
__try
{
const _Node* __ht_n = __ht._M_buckets[__ht._M_begin_bucket_index];
if (!__ht_n)
return;
// Note that the copy constructor do not rely on hash code usage.
// First deal with the special first node that is directly store in
// the first non-empty bucket
_Node* __this_n = _M_allocate_node(__ht_n->_M_v);
this->_M_copy_code(__this_n, __ht_n);
_M_buckets[_M_begin_bucket_index] = __this_n;
__ht_n = __ht_n->_M_next;
// Second deal with following non-empty buckets containing previous
// nodes node.
for (size_type __i = __ht._M_begin_bucket_index + 1;
__i != __ht._M_bucket_count; ++__i)
{
if (!__ht._M_buckets[__i])
continue;
for (; __ht_n != __ht._M_buckets[__i]->_M_next;
__ht_n = __ht_n->_M_next)
{
__this_n->_M_next = _M_allocate_node(__ht_n->_M_v);
this->_M_copy_code(__this_n->_M_next, __ht_n);
__this_n = __this_n->_M_next;
}
_M_buckets[__i] = __this_n;
}
// Last finalize copy of the nodes of the last non-empty bucket
for (; __ht_n; __ht_n = __ht_n->_M_next)
{
__this_n->_M_next = _M_allocate_node(__ht_n->_M_v);
this->_M_copy_code(__this_n->_M_next, __ht_n);
__this_n = __this_n->_M_next;
}
}
__catch(...)
{
clear();
_M_deallocate_buckets(_M_buckets, _M_bucket_count);
__throw_exception_again;
}
}
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_Hashtable(_Hashtable&& __ht)
: __detail::_Rehash_base<_RehashPolicy, _Hashtable>(__ht),
__detail::_Hash_code_base<_Key, _Value, _ExtractKey, _Equal,
_H1, _H2, _Hash, __chc>(__ht),
__detail::_Map_base<_Key, _Value, _ExtractKey, __uk, _Hashtable>(__ht),
_M_node_allocator(std::move(__ht._M_node_allocator)),
_M_buckets(__ht._M_buckets),
_M_bucket_count(__ht._M_bucket_count),
_M_begin_bucket_index(__ht._M_begin_bucket_index),
_M_element_count(__ht._M_element_count),
_M_rehash_policy(__ht._M_rehash_policy)
{
__ht._M_rehash_policy = _RehashPolicy();
__ht._M_bucket_count = __ht._M_rehash_policy._M_next_bkt(0);
__ht._M_buckets = __ht._M_allocate_buckets(__ht._M_bucket_count);
__ht._M_begin_bucket_index = __ht._M_bucket_count;
__ht._M_element_count = 0;
}
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
~_Hashtable() noexcept
{
clear();
_M_deallocate_buckets(_M_buckets, _M_bucket_count);
}
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
void
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
swap(_Hashtable& __x)
{
// The only base class with member variables is hash_code_base. We
// define _Hash_code_base::_M_swap because different specializations
// have different members.
__detail::_Hash_code_base<_Key, _Value, _ExtractKey, _Equal,
_H1, _H2, _Hash, __chc>::_M_swap(__x);
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 431. Swapping containers with unequal allocators.
std::__alloc_swap<_Node_allocator_type>::_S_do_it(_M_node_allocator,
__x._M_node_allocator);
std::swap(_M_rehash_policy, __x._M_rehash_policy);
std::swap(_M_buckets, __x._M_buckets);
std::swap(_M_bucket_count, __x._M_bucket_count);
std::swap(_M_begin_bucket_index, __x._M_begin_bucket_index);
std::swap(_M_element_count, __x._M_element_count);
}
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
void
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
__rehash_policy(const _RehashPolicy& __pol)
{
size_type __n_bkt = __pol._M_bkt_for_elements(_M_element_count);
if (__n_bkt != _M_bucket_count)
_M_rehash(__n_bkt, _M_rehash_policy._M_state());
_M_rehash_policy = __pol;
}
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
typename _Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy,
__chc, __cit, __uk>::iterator
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
find(const key_type& __k)
{
typename _Hashtable::_Hash_code_type __code = this->_M_hash_code(__k);
std::size_t __n = this->_M_bucket_index(__k, __code, _M_bucket_count);
_Node* __p = _M_find_node(__n, __k, __code);
return __p ? iterator(__p) : this->end();
}
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
typename _Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy,
__chc, __cit, __uk>::const_iterator
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
find(const key_type& __k) const
{
typename _Hashtable::_Hash_code_type __code = this->_M_hash_code(__k);
std::size_t __n = this->_M_bucket_index(__k, __code, _M_bucket_count);
_Node* __p = _M_find_node(__n, __k, __code);
return __p ? const_iterator(__p) : this->end();
}
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
typename _Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy,
__chc, __cit, __uk>::size_type
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
count(const key_type& __k) const
{
typename _Hashtable::_Hash_code_type __code = this->_M_hash_code(__k);
std::size_t __n = this->_M_bucket_index(__k, __code, _M_bucket_count);
_Node* __p = _M_bucket_begin(__n);
if (!__p)
return 0;
std::size_t __result = 0;
for (;; __p = __p->_M_next)
{
if (this->_M_compare(__k, __code, __p))
++__result;
else if (__result)
// All equivalent values are next to each other, if we found a not
// equivalent value after an equivalent one it means that we won't
// find anymore an equivalent value.
break;
if (!__p->_M_next
|| this->_M_bucket_index(__p->_M_next, _M_bucket_count)
!= __n)
break;
}
return __result;
}
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
std::pair<typename _Hashtable<_Key, _Value, _Allocator,
_ExtractKey, _Equal, _H1,
_H2, _Hash, _RehashPolicy,
__chc, __cit, __uk>::iterator,
typename _Hashtable<_Key, _Value, _Allocator,
_ExtractKey, _Equal, _H1,
_H2, _Hash, _RehashPolicy,
__chc, __cit, __uk>::iterator>
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
equal_range(const key_type& __k)
{
typename _Hashtable::_Hash_code_type __code = this->_M_hash_code(__k);
std::size_t __n = this->_M_bucket_index(__k, __code, _M_bucket_count);
_Node* __p = _M_find_node(__n, __k, __code);
if (__p)
{
_Node* __p1 = __p->_M_next;
while (__p1
&& this->_M_bucket_index(__p1, _M_bucket_count) == __n
&& this->_M_compare(__k, __code, __p1))
__p1 = __p1->_M_next;
return std::make_pair(iterator(__p), iterator(__p1));
}
else
return std::make_pair(this->end(), this->end());
}
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
std::pair<typename _Hashtable<_Key, _Value, _Allocator,
_ExtractKey, _Equal, _H1,
_H2, _Hash, _RehashPolicy,
__chc, __cit, __uk>::const_iterator,
typename _Hashtable<_Key, _Value, _Allocator,
_ExtractKey, _Equal, _H1,
_H2, _Hash, _RehashPolicy,
__chc, __cit, __uk>::const_iterator>
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
equal_range(const key_type& __k) const
{
typename _Hashtable::_Hash_code_type __code = this->_M_hash_code(__k);
std::size_t __n = this->_M_bucket_index(__k, __code, _M_bucket_count);
_Node* __p = _M_find_node(__n, __k, __code);
if (__p)
{
_Node* __p1 = __p->_M_next;
while (__p1
&& this->_M_bucket_index(__p1, _M_bucket_count) == __n
&& this->_M_compare(__k, __code, __p1))
__p1 = __p1->_M_next;
return std::make_pair(const_iterator(__p), const_iterator(__p1));
}
else
return std::make_pair(this->end(), this->end());
}
// Find the node whose key compares equal to k in the bucket n. Return nullptr
// if no node is found.
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
typename _Hashtable<_Key, _Value, _Allocator, _ExtractKey,
_Equal, _H1, _H2, _Hash, _RehashPolicy,
__chc, __cit, __uk>::_Node*
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_M_find_node(size_type __n, const key_type& __k,
typename _Hashtable::_Hash_code_type __code) const
{
_Node* __p = _M_bucket_begin(__n);
if (!__p)
return nullptr;
for (;; __p = __p->_M_next)
{
if (this->_M_compare(__k, __code, __p))
return __p;
if (!(__p->_M_next)
|| this->_M_bucket_index(__p->_M_next, _M_bucket_count) != __n)
break;
}
return nullptr;
}
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
void
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_M_insert_bucket_begin(size_type __bkt, _Node* __new_node)
{
_Node* __prev_n;
if (__bkt < _M_begin_bucket_index)
{
if (_M_begin_bucket_index != _M_bucket_count)
{
__new_node->_M_next = _M_buckets[_M_begin_bucket_index];
_M_buckets[_M_begin_bucket_index] = __new_node;
}
__prev_n = __new_node;
_M_begin_bucket_index = __bkt;
}
else
{
// We need to find previous non-empty bucket to link the new node.
// There are several ways to find this previous bucket:
// 1. Move backward until we find it (the current method)
// 2. Start from the begin bucket index and move forward until we
// cross __n position.
// 3. Move forward until we find a non-empty bucket that will
// contain the previous node.
size_type __prev_bkt;
for (__prev_bkt = __bkt; __prev_bkt-- != 0;)
if (_M_buckets[__prev_bkt])
break;
__prev_n = _M_bucket_end(__prev_bkt);
_M_insert_after(__prev_bkt, __prev_n, __new_node);
}
_M_buckets[__bkt] = __prev_n;
}
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
void
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_M_insert_after(size_type __bkt, _Node* __prev_n, _Node* __new_n)
{
if (__prev_n->_M_next)
{
size_type __next_bkt =
this->_M_bucket_index(__prev_n->_M_next, _M_bucket_count);
if (__next_bkt != __bkt)
_M_buckets[__next_bkt] = __new_n;
}
__new_n->_M_next = __prev_n->_M_next;
__prev_n->_M_next = __new_n;
}
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
void
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_M_remove_bucket_begin(size_type __bkt, _Node* __next, size_type __next_bkt)
{
if (!__next || __next_bkt != __bkt)
{
// Bucket is now empty
if (__next && __next_bkt != __bkt)
// Update next non-empty bucket before begin node
_M_buckets[__next_bkt] = _M_buckets[__bkt];
_M_buckets[__bkt] = nullptr;
if (__bkt == _M_begin_bucket_index)
// We need to update begin bucket index
if (__next)
{
_M_begin_bucket_index = __next_bkt;
_M_buckets[_M_begin_bucket_index] = __next;
}
else
_M_begin_bucket_index = _M_bucket_count;
}
else if (__bkt == _M_begin_bucket_index)
_M_buckets[__bkt] = __next;
}
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
typename _Hashtable<_Key, _Value, _Allocator, _ExtractKey,
_Equal, _H1, _H2, _Hash, _RehashPolicy,
__chc, __cit, __uk>::_Node*
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_M_get_previous_node(size_type __bkt, _Node* __n)
{
_Node* __prev_n = nullptr;
if (__bkt != _M_begin_bucket_index || __n != _M_buckets[__bkt])
{
__prev_n = _M_buckets[__bkt];
while (__prev_n->_M_next != __n)
__prev_n = __prev_n->_M_next;
}
return __prev_n;
}
// Insert v in bucket n (assumes no element with its key already present).
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
template<typename _Arg>
typename _Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy,
__chc, __cit, __uk>::iterator
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_M_insert_bucket(_Arg&& __v, size_type __n,
typename _Hashtable::_Hash_code_type __code)
{
const _RehashPolicyState& __saved_state = _M_rehash_policy._M_state();
std::pair<bool, std::size_t> __do_rehash
= _M_rehash_policy._M_need_rehash(_M_bucket_count,
_M_element_count, 1);
if (__do_rehash.first)
{
const key_type& __k = this->_M_extract(__v);
__n = this->_M_bucket_index(__k, __code, __do_rehash.second);
}
_Node* __new_node = nullptr;
__try
{
// Allocate the new node before doing the rehash so that we
// don't do a rehash if the allocation throws.
__new_node = _M_allocate_node(std::forward<_Arg>(__v));
this->_M_store_code(__new_node, __code);
if (__do_rehash.first)
_M_rehash(__do_rehash.second, __saved_state);
if (_M_buckets[__n])
_M_insert_after(__n, _M_buckets[__n], __new_node);
else
_M_insert_bucket_begin(__n, __new_node);
++_M_element_count;
return iterator(__new_node);
}
__catch(...)
{
if (!__new_node)
_M_rehash_policy._M_reset(__saved_state);
else
_M_deallocate_node(__new_node);
__throw_exception_again;
}
}
// Insert v if no element with its key is already present.
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
template<typename _Arg>
std::pair<typename _Hashtable<_Key, _Value, _Allocator,
_ExtractKey, _Equal, _H1,
_H2, _Hash, _RehashPolicy,
__chc, __cit, __uk>::iterator, bool>
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_M_insert(_Arg&& __v, std::true_type)
{
const key_type& __k = this->_M_extract(__v);
typename _Hashtable::_Hash_code_type __code = this->_M_hash_code(__k);
size_type __n = this->_M_bucket_index(__k, __code, _M_bucket_count);
if (_Node* __p = _M_find_node(__n, __k, __code))
return std::make_pair(iterator(__p), false);
return std::make_pair(_M_insert_bucket(std::forward<_Arg>(__v),
__n, __code), true);
}
// Insert v unconditionally.
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
template<typename _Arg>
typename _Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy,
__chc, __cit, __uk>::iterator
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_M_insert(_Arg&& __v, std::false_type)
{
const _RehashPolicyState& __saved_state = _M_rehash_policy._M_state();
std::pair<bool, std::size_t> __do_rehash
= _M_rehash_policy._M_need_rehash(_M_bucket_count,
_M_element_count, 1);
const key_type& __k = this->_M_extract(__v);
typename _Hashtable::_Hash_code_type __code = this->_M_hash_code(__k);
size_type __n = this->_M_bucket_index(__k, __code, _M_bucket_count);
// First find the node, avoid leaking new_node if compare throws.
_Node* __prev = _M_find_node(__n, __k, __code);
_Node* __new_node = nullptr;
__try
{
// Second allocate new node so that we don't rehash if it throws
__new_node = _M_allocate_node(std::forward<_Arg>(__v));
this->_M_store_code(__new_node, __code);
if (__do_rehash.first)
{
_M_rehash(__do_rehash.second, __saved_state);
__n = this->_M_bucket_index(__k, __code, _M_bucket_count);
// __prev is still valid because rehash do not invalidate nodes
}
if (__prev)
// Insert after the previous equivalent node
_M_insert_after(__n, __prev, __new_node);
else if (_M_buckets[__n])
// Bucket is not empty and the inserted node has no equivalent in
// the hashtable. We must insert the new node at the beginning or
// end of the bucket to preserve equivalent elements relative
// positions.
if (__n != _M_begin_bucket_index)
// We insert the new node at the beginning
_M_insert_after(__n, _M_buckets[__n], __new_node);
else
// We insert the new node at the end
_M_insert_after(__n, _M_bucket_end(__n), __new_node);
else
_M_insert_bucket_begin(__n, __new_node);
++_M_element_count;
return iterator(__new_node);
}
__catch(...)
{
if (!__new_node)
_M_rehash_policy._M_reset(__saved_state);
else
_M_deallocate_node(__new_node);
__throw_exception_again;
}
}
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
template<typename _InputIterator>
void
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
insert(_InputIterator __first, _InputIterator __last)
{
size_type __n_elt = __detail::__distance_fw(__first, __last);
const _RehashPolicyState& __saved_state = _M_rehash_policy._M_state();
std::pair<bool, std::size_t> __do_rehash
= _M_rehash_policy._M_need_rehash(_M_bucket_count,
_M_element_count, __n_elt);
if (__do_rehash.first)
_M_rehash(__do_rehash.second, __saved_state);
for (; __first != __last; ++__first)
this->insert(*__first);
}
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
typename _Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy,
__chc, __cit, __uk>::iterator
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
erase(const_iterator __it)
{
_Node* __n = __it._M_cur;
std::size_t __bkt = this->_M_bucket_index(__n, _M_bucket_count);
// Look for previous node to unlink it from the erased one, this is why
// we need buckets to contain the before begin node of the bucket to make
// this research fast.
_Node* __prev_n = _M_get_previous_node(__bkt, __n);
if (__n == _M_bucket_begin(__bkt))
_M_remove_bucket_begin(__bkt, __n->_M_next,
__n->_M_next ? this->_M_bucket_index(__n->_M_next, _M_bucket_count)
: 0);
else if (__n->_M_next)
{
size_type __next_bkt =
this->_M_bucket_index(__n->_M_next, _M_bucket_count);
if (__next_bkt != __bkt)
_M_buckets[__next_bkt] = __prev_n;
}
if (__prev_n)
__prev_n->_M_next = __n->_M_next;
iterator __result(__n->_M_next);
_M_deallocate_node(__n);
--_M_element_count;
return __result;
}
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
typename _Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy,
__chc, __cit, __uk>::size_type
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
erase(const key_type& __k)
{
typename _Hashtable::_Hash_code_type __code = this->_M_hash_code(__k);
std::size_t __bkt = this->_M_bucket_index(__k, __code, _M_bucket_count);
// Look for the first matching node with its previous node at the same
// time
_Node* __n = _M_buckets[__bkt];
if (!__n)
return 0;
_Node* __prev_n = nullptr;
if (__bkt != _M_begin_bucket_index)
{
__prev_n = __n;
__n = __n->_M_next;
}
bool __is_bucket_begin = true;
for (;; __prev_n = __n, __n = __n->_M_next)
{
if (this->_M_compare(__k, __code, __n))
break;
if (!(__n->_M_next)
|| this->_M_bucket_index(__n->_M_next, _M_bucket_count) != __bkt)
return 0;
__is_bucket_begin = false;
}
// We found a matching node, start deallocation loop from it
std::size_t __next_bkt = __bkt;
_Node* __next_n = __n;
size_type __result = 0;
_Node* __saved_n = nullptr;
do
{
_Node* __p = __next_n;
__next_n = __p->_M_next;
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 526. Is it undefined if a function in the standard changes
// in parameters?
if (std::__addressof(this->_M_extract(__p->_M_v))
!= std::__addressof(__k))
_M_deallocate_node(__p);
else
__saved_n = __p;
--_M_element_count;
++__result;
if (!__next_n)
break;
__next_bkt = this->_M_bucket_index(__next_n, _M_bucket_count);
}
while (__next_bkt == __bkt && this->_M_compare(__k, __code, __next_n));
if (__saved_n)
_M_deallocate_node(__saved_n);
if (__is_bucket_begin)
_M_remove_bucket_begin(__bkt, __next_n, __next_bkt);
else if (__next_n && __next_bkt != __bkt)
_M_buckets[__next_bkt] = __prev_n;
if (__prev_n)
__prev_n->_M_next = __next_n;
return __result;
}
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
typename _Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy,
__chc, __cit, __uk>::iterator
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
erase(const_iterator __first, const_iterator __last)
{
_Node* __n = __first._M_cur;
_Node* __last_n = __last._M_cur;
if (__n == __last_n)
return iterator(__n);
std::size_t __bkt = this->_M_bucket_index(__n, _M_bucket_count);
_Node* __prev_n = _M_get_previous_node(__bkt, __n);
bool __is_bucket_begin = __n == _M_bucket_begin(__bkt);
std::size_t __n_bkt = __bkt;
for (;;)
{
do
{
_Node* __tmp = __n;
__n = __n->_M_next;
_M_deallocate_node(__tmp);
--_M_element_count;
if (!__n)
break;
__n_bkt = this->_M_bucket_index(__n, _M_bucket_count);
}
while (__n != __last_n && __n_bkt == __bkt);
if (__is_bucket_begin)
_M_remove_bucket_begin(__bkt, __n, __n_bkt);
if (__n == __last_n)
break;
__is_bucket_begin = true;
__bkt = __n_bkt;
}
if (__n && __n_bkt != __bkt)
_M_buckets[__n_bkt] = __prev_n;
if (__prev_n)
__prev_n->_M_next = __n;
return iterator(__n);
}
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
void
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
clear() noexcept
{
_M_deallocate_nodes(_M_buckets[_M_begin_bucket_index]);
__builtin_memset(_M_buckets, 0, _M_bucket_count * sizeof(_Bucket));
_M_element_count = 0;
_M_begin_bucket_index = _M_bucket_count;
}
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
void
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
rehash(size_type __n)
{
const _RehashPolicyState& __saved_state = _M_rehash_policy._M_state();
_M_rehash(std::max(_M_rehash_policy._M_next_bkt(__n),
_M_rehash_policy._M_bkt_for_elements(_M_element_count
+ 1)),
__saved_state);
}
template<typename _Key, typename _Value,
typename _Allocator, typename _ExtractKey, typename _Equal,
typename _H1, typename _H2, typename _Hash, typename _RehashPolicy,
bool __chc, bool __cit, bool __uk>
void
_Hashtable<_Key, _Value, _Allocator, _ExtractKey, _Equal,
_H1, _H2, _Hash, _RehashPolicy, __chc, __cit, __uk>::
_M_rehash(size_type __n, const _RehashPolicyState& __state)
{
_Bucket* __new_buckets = nullptr;
_Node* __p = _M_buckets[_M_begin_bucket_index];
__try
{
__new_buckets = _M_allocate_buckets(__n);
// First loop to store each node in its new bucket
while (__p)
{
_Node* __next = __p->_M_next;
std::size_t __new_index = this->_M_bucket_index(__p, __n);
if (!__new_buckets[__new_index])
// Store temporarily bucket end node in _M_buckets if possible.
// This will boost second loop where we need to access bucket
// end node quickly.
if (__new_index < _M_bucket_count)
_M_buckets[__new_index] = __p;
__p->_M_next = __new_buckets[__new_index];
__new_buckets[__new_index] = __p;
__p = __next;
}
_M_begin_bucket_index = __n;
_Node* __prev_node = nullptr;
// Second loop to link all nodes together and to fix bucket values so
// that they contain the before begin node of the bucket.
for (size_type __i = 0; __i != __n; ++__i)
if (__new_buckets[__i])
{
if (__prev_node)
{
__prev_node->_M_next = __new_buckets[__i];
__new_buckets[__i] = __prev_node;
}
else
_M_begin_bucket_index = __i;
if (__i < _M_bucket_count)
__prev_node = _M_buckets[__i];
else
{
__prev_node = __new_buckets[__i];
while (__prev_node->_M_next)
__prev_node = __prev_node->_M_next;
}
}
_M_deallocate_buckets(_M_buckets, _M_bucket_count);
_M_bucket_count = __n;
_M_buckets = __new_buckets;
}
__catch(...)
{
if (__new_buckets)
{
// A failure here means that a hash function threw an exception.
// We can't restore the previous state without calling the hash
// function again, so the only sensible recovery is to delete
// everything.
_M_deallocate_nodes(__new_buckets, __n);
_M_deallocate_buckets(__new_buckets, __n);
_M_deallocate_nodes(__p);
__builtin_memset(_M_buckets, 0, sizeof(_Bucket) * _M_bucket_count);
_M_element_count = 0;
_M_begin_bucket_index = _M_bucket_count;
_M_rehash_policy._M_reset(_RehashPolicyState());
}
else
// A failure here means that buckets allocation failed. We only
// have to restore hash policy previous state.
_M_rehash_policy._M_reset(__state);
__throw_exception_again;
}
}
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace std
#endif // _HASHTABLE_H