unordered_base.h
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// Profiling unordered containers implementation details -*- C++ -*-
// Copyright (C) 2013 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 along
// with this library; see the file COPYING3. If not see
// <http://www.gnu.org/licenses/>.
/** @file profile/unordered_base.h
* This file is a GNU profile extension to the Standard C++ Library.
*/
#ifndef _GLIBCXX_PROFILE_UNORDERED
#define _GLIBCXX_PROFILE_UNORDERED 1
namespace std _GLIBCXX_VISIBILITY(default)
{
namespace __profile
{
template<typename _UnorderedCont,
typename _Value, bool _Cache_hash_code>
struct _Bucket_index_helper;
template<typename _UnorderedCont, typename _Value>
struct _Bucket_index_helper<_UnorderedCont, _Value, true>
{
static std::size_t
bucket(const _UnorderedCont& __uc,
const __detail::_Hash_node<_Value, true>* __node)
{ return __node->_M_hash_code % __uc.bucket_count(); }
};
template<typename _UnorderedCont, typename _Value>
struct _Bucket_index_helper<_UnorderedCont, _Value, false>
{
static std::size_t
bucket(const _UnorderedCont& __uc,
const __detail::_Hash_node<_Value, false>* __node)
{ return __uc.bucket(__node->_M_v()); }
};
template<typename _UnorderedCont, typename _Key, typename _Mapped>
struct _Bucket_index_helper<_UnorderedCont,
std::pair<const _Key, _Mapped>, false>
{
typedef std::pair<const _Key, _Mapped> _Value;
static std::size_t
bucket(const _UnorderedCont& __uc,
const __detail::_Hash_node<_Value, false>* __node)
{ return __uc.bucket(__node->_M_v().first); }
};
template<typename _UnorderedCont, typename _Value, bool _Cache_hash_code>
std::size_t
__get_bucket_index(const _UnorderedCont& __uc,
const __detail::_Hash_node<_Value, _Cache_hash_code>* __node)
{
using __bucket_index_helper
= _Bucket_index_helper<_UnorderedCont, _Value, _Cache_hash_code>;
return __bucket_index_helper::bucket(__uc, __node);
}
template<typename _UnorderedCont,
typename _Value, bool _Cache_hash_code>
struct _Equal_helper;
template<typename _UnorderedCont, typename _Value>
struct _Equal_helper<_UnorderedCont, _Value, true>
{
static std::size_t
are_equal(const _UnorderedCont& __uc,
const __detail::_Hash_node<_Value, true>* __lhs,
const __detail::_Hash_node<_Value, true>* __rhs)
{
return __lhs->_M_hash_code == __rhs->_M_hash_code
&& __uc.key_eq()(__lhs->_M_v(), __rhs->_M_v());
}
};
template<typename _UnorderedCont,
typename _Value>
struct _Equal_helper<_UnorderedCont, _Value, false>
{
static std::size_t
are_equal(const _UnorderedCont& __uc,
const __detail::_Hash_node<_Value, false>* __lhs,
const __detail::_Hash_node<_Value, false>* __rhs)
{ return __uc.key_eq()(__lhs->_M_v(), __rhs->_M_v()); }
};
template<typename _UnorderedCont,
typename _Key, typename _Mapped>
struct _Equal_helper<_UnorderedCont, std::pair<const _Key, _Mapped>, true>
{
typedef std::pair<const _Key, _Mapped> _Value;
static std::size_t
are_equal(const _UnorderedCont& __uc,
const __detail::_Hash_node<_Value, true>* __lhs,
const __detail::_Hash_node<_Value, true>* __rhs)
{
return __lhs->_M_hash_code == __rhs->_M_hash_code
&& __uc.key_eq()(__lhs->_M_v().first, __rhs->_M_v().first);
}
};
template<typename _UnorderedCont,
typename _Key, typename _Mapped>
struct _Equal_helper<_UnorderedCont, std::pair<const _Key, _Mapped>, false>
{
typedef std::pair<const _Key, _Mapped> _Value;
static std::size_t
are_equal(const _UnorderedCont& __uc,
const __detail::_Hash_node<_Value, false>* __lhs,
const __detail::_Hash_node<_Value, false>* __rhs)
{ return __uc.key_eq()(__lhs->_M_v().first, __rhs->_M_v().first); }
};
template<typename _UnorderedCont, typename _Value, bool _Cache_hash_code>
bool
__are_equal(const _UnorderedCont& __uc,
const __detail::_Hash_node<_Value, _Cache_hash_code>* __lhs,
const __detail::_Hash_node<_Value, _Cache_hash_code>* __rhs)
{
using __equal_helper
= _Equal_helper<_UnorderedCont, _Value, _Cache_hash_code>;
return __equal_helper::are_equal(__uc, __lhs, __rhs);
}
template<typename _UnorderedCont, bool _Unique_keys>
class _Unordered_profile
{
_UnorderedCont&
_M_conjure()
{ return *(static_cast<_UnorderedCont*>(this)); }
using __unique_keys = std::integral_constant<bool, _Unique_keys>;
protected:
_Unordered_profile()
{
auto& __uc = _M_conjure();
__profcxx_hashtable_construct(&__uc, __uc.bucket_count());
__profcxx_hashtable_construct2(&__uc);
}
_Unordered_profile(const _Unordered_profile&)
: _Unordered_profile() { }
_Unordered_profile(_Unordered_profile&&)
: _Unordered_profile() { }
~_Unordered_profile() noexcept
{
auto& __uc = _M_conjure();
__profcxx_hashtable_destruct(&__uc, __uc.bucket_count(), __uc.size());
_M_profile_destruct();
}
_Unordered_profile&
operator=(const _Unordered_profile&) = default;
_Unordered_profile&
operator=(_Unordered_profile&&) = default;
void
_M_profile_destruct()
{
if (!__profcxx_inefficient_hash_is_on())
return;
_M_profile_destruct(__unique_keys());
}
private:
void
_M_profile_destruct(std::true_type);
void
_M_profile_destruct(std::false_type);
};
template<typename _UnorderedCont, bool _Unique_keys>
void
_Unordered_profile<_UnorderedCont, _Unique_keys>::
_M_profile_destruct(std::true_type)
{
auto& __uc = _M_conjure();
std::size_t __hops = 0, __lc = 0, __chain = 0;
auto __it = __uc.begin();
while (__it != __uc.end())
{
auto __bkt = __get_bucket_index(__uc, __it._M_cur);
auto __lit = __uc.begin(__bkt);
auto __lend = __uc.end(__bkt);
for (++__it, ++__lit; __lit != __lend; ++__it, ++__lit)
++__chain;
if (__chain)
{
++__chain;
__lc = __lc > __chain ? __lc : __chain;
__hops += __chain * (__chain - 1) / 2;
__chain = 0;
}
}
__profcxx_hashtable_destruct2(&__uc, __lc, __uc.size(), __hops);
}
template<typename _UnorderedCont, bool _Unique_keys>
void
_Unordered_profile<_UnorderedCont, _Unique_keys>::
_M_profile_destruct(std::false_type)
{
auto& __uc = _M_conjure();
std::size_t __hops = 0, __lc = 0, __chain = 0, __unique_size = 0;
auto __it = __uc.begin();
while (__it != __uc.end())
{
auto __bkt = __get_bucket_index(__uc, __it._M_cur);
auto __lit = __uc.begin(__bkt);
auto __lend = __uc.end(__bkt);
auto __pit = __it;
++__unique_size;
for (++__it, ++__lit; __lit != __lend; ++__it, ++__lit)
{
if (!__are_equal(__uc, __pit._M_cur, __it._M_cur))
{
++__chain;
++__unique_size;
__pit = __it;
}
}
if (__chain)
{
++__chain;
__lc = __lc > __chain ? __lc : __chain;
__hops += __chain * (__chain - 1) / 2;
__chain = 0;
}
}
__profcxx_hashtable_destruct2(&__uc, __lc, __unique_size, __hops);
}
} // namespace __profile
} // namespace std
#endif