stl_construct.h
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// nonstandard construct and destroy functions -*- C++ -*-
// Copyright (C) 2001-2018 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/>.
/*
*
* Copyright (c) 1994
* Hewlett-Packard Company
*
* Permission to use, copy, modify, distribute and sell this software
* and its documentation for any purpose is hereby granted without fee,
* provided that the above copyright notice appear in all copies and
* that both that copyright notice and this permission notice appear
* in supporting documentation. Hewlett-Packard Company makes no
* representations about the suitability of this software for any
* purpose. It is provided "as is" without express or implied warranty.
*
*
* Copyright (c) 1996,1997
* Silicon Graphics Computer Systems, Inc.
*
* Permission to use, copy, modify, distribute and sell this software
* and its documentation for any purpose is hereby granted without fee,
* provided that the above copyright notice appear in all copies and
* that both that copyright notice and this permission notice appear
* in supporting documentation. Silicon Graphics makes no
* representations about the suitability of this software for any
* purpose. It is provided "as is" without express or implied warranty.
*/
/** @file bits/stl_construct.h
* This is an internal header file, included by other library headers.
* Do not attempt to use it directly. @headername{memory}
*/
#ifndef _STL_CONSTRUCT_H
#define _STL_CONSTRUCT_H 1
#include <new>
#include <bits/move.h>
#include <ext/alloc_traits.h>
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
/**
* Constructs an object in existing memory by invoking an allocated
* object's constructor with an initializer.
*/
#if __cplusplus >= 201103L
template<typename _T1, typename... _Args>
inline void
_Construct(_T1* __p, _Args&&... __args)
{ ::new(static_cast<void*>(__p)) _T1(std::forward<_Args>(__args)...); }
#else
template<typename _T1, typename _T2>
inline void
_Construct(_T1* __p, const _T2& __value)
{
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 402. wrong new expression in [some_]allocator::construct
::new(static_cast<void*>(__p)) _T1(__value);
}
#endif
template<typename _T1>
inline void
_Construct_novalue(_T1* __p)
{ ::new(static_cast<void*>(__p)) _T1; }
/**
* Destroy the object pointed to by a pointer type.
*/
template<typename _Tp>
inline void
_Destroy(_Tp* __pointer)
{ __pointer->~_Tp(); }
template<bool>
struct _Destroy_aux
{
template<typename _ForwardIterator>
static void
__destroy(_ForwardIterator __first, _ForwardIterator __last)
{
for (; __first != __last; ++__first)
std::_Destroy(std::__addressof(*__first));
}
};
template<>
struct _Destroy_aux<true>
{
template<typename _ForwardIterator>
static void
__destroy(_ForwardIterator, _ForwardIterator) { }
};
/**
* Destroy a range of objects. If the value_type of the object has
* a trivial destructor, the compiler should optimize all of this
* away, otherwise the objects' destructors must be invoked.
*/
template<typename _ForwardIterator>
inline void
_Destroy(_ForwardIterator __first, _ForwardIterator __last)
{
typedef typename iterator_traits<_ForwardIterator>::value_type
_Value_type;
#if __cplusplus >= 201103L
// A deleted destructor is trivial, this ensures we reject such types:
static_assert(is_destructible<_Value_type>::value,
"value type is destructible");
#endif
std::_Destroy_aux<__has_trivial_destructor(_Value_type)>::
__destroy(__first, __last);
}
template<bool>
struct _Destroy_n_aux
{
template<typename _ForwardIterator, typename _Size>
static _ForwardIterator
__destroy_n(_ForwardIterator __first, _Size __count)
{
for (; __count > 0; (void)++__first, --__count)
std::_Destroy(std::__addressof(*__first));
return __first;
}
};
template<>
struct _Destroy_n_aux<true>
{
template<typename _ForwardIterator, typename _Size>
static _ForwardIterator
__destroy_n(_ForwardIterator __first, _Size __count)
{
std::advance(__first, __count);
return __first;
}
};
/**
* Destroy a range of objects. If the value_type of the object has
* a trivial destructor, the compiler should optimize all of this
* away, otherwise the objects' destructors must be invoked.
*/
template<typename _ForwardIterator, typename _Size>
inline _ForwardIterator
_Destroy_n(_ForwardIterator __first, _Size __count)
{
typedef typename iterator_traits<_ForwardIterator>::value_type
_Value_type;
#if __cplusplus >= 201103L
// A deleted destructor is trivial, this ensures we reject such types:
static_assert(is_destructible<_Value_type>::value,
"value type is destructible");
#endif
return std::_Destroy_n_aux<__has_trivial_destructor(_Value_type)>::
__destroy_n(__first, __count);
}
/**
* Destroy a range of objects using the supplied allocator. For
* nondefault allocators we do not optimize away invocation of
* destroy() even if _Tp has a trivial destructor.
*/
template<typename _ForwardIterator, typename _Allocator>
void
_Destroy(_ForwardIterator __first, _ForwardIterator __last,
_Allocator& __alloc)
{
typedef __gnu_cxx::__alloc_traits<_Allocator> __traits;
for (; __first != __last; ++__first)
__traits::destroy(__alloc, std::__addressof(*__first));
}
template<typename _ForwardIterator, typename _Tp>
inline void
_Destroy(_ForwardIterator __first, _ForwardIterator __last,
allocator<_Tp>&)
{
_Destroy(__first, __last);
}
#if __cplusplus > 201402L
template <typename _Tp>
inline void
destroy_at(_Tp* __location)
{
std::_Destroy(__location);
}
template <typename _ForwardIterator>
inline void
destroy(_ForwardIterator __first, _ForwardIterator __last)
{
std::_Destroy(__first, __last);
}
template <typename _ForwardIterator, typename _Size>
inline _ForwardIterator
destroy_n(_ForwardIterator __first, _Size __count)
{
return std::_Destroy_n(__first, __count);
}
#endif
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace std
#endif /* _STL_CONSTRUCT_H */
move.h
std::_Construct
void _Construct(_T1 *__p, _Args &&... __args)
Definition: stl_construct.h:74
alloc_traits.h
std::__addressof
constexpr _Tp * __addressof(_Tp &__r) noexcept
Same as C++11 std::addressof.
Definition: move.h:47
std::_Destroy_n
_ForwardIterator _Destroy_n(_ForwardIterator __first, _Size __count)
Definition: stl_construct.h:172
std
ISO C++ entities toplevel namespace is std.
__gnu_cxx::__alloc_traits
Uniform interface to C++98 and C++11 allocators.
Definition: ext/alloc_traits.h:50
new
std::allocator
The standard allocator, as per [20.4].
Definition: allocator.h:108
std::_Destroy
void _Destroy(_Tp *__pointer)
Definition: stl_construct.h:97
std::is_destructible
is_destructible
Definition: type_traits:830
std::advance
_GLIBCXX17_CONSTEXPR void advance(_InputIterator &__i, _Distance __n)
A generalization of pointer arithmetic.
Definition: stl_iterator_base_funcs.h:202