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// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#ifndef _LIBCPP___MEMORY_CONSTRUCT_AT_H
#define _LIBCPP___MEMORY_CONSTRUCT_AT_H
#include <__assert>
#include <__config>
#include <__iterator/access.h>
#include <__memory/addressof.h>
#include <__memory/voidify.h>
#include <__utility/forward.h>
#include <__utility/move.h>
#include <type_traits>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
#endif
_LIBCPP_BEGIN_NAMESPACE_STD
// construct_at
#if _LIBCPP_STD_VER > 17
template <class _Tp, class... _Args, class = decltype(::new(declval<void*>()) _Tp(declval<_Args>()...))>
_LIBCPP_HIDE_FROM_ABI constexpr _Tp* construct_at(_Tp* __location, _Args&&... __args) {
_LIBCPP_ASSERT(__location != nullptr, "null pointer given to construct_at");
return ::new (_VSTD::__voidify(*__location)) _Tp(_VSTD::forward<_Args>(__args)...);
}
#endif
template <class _Tp, class... _Args, class = decltype(::new(declval<void*>()) _Tp(declval<_Args>()...))>
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _Tp* __construct_at(_Tp* __location, _Args&&... __args) {
#if _LIBCPP_STD_VER > 17
return std::construct_at(__location, std::forward<_Args>(__args)...);
#else
return ::new (std::__voidify(*__location)) _Tp(std::forward<_Args>(__args)...);
#endif
}
// destroy_at
// The internal functions are available regardless of the language version (with the exception of the `__destroy_at`
// taking an array).
template <class _ForwardIterator>
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX17
_ForwardIterator __destroy(_ForwardIterator, _ForwardIterator);
template <class _Tp, typename enable_if<!is_array<_Tp>::value, int>::type = 0>
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX17
void __destroy_at(_Tp* __loc) {
_LIBCPP_ASSERT(__loc != nullptr, "null pointer given to destroy_at");
__loc->~_Tp();
}
#if _LIBCPP_STD_VER > 17
template <class _Tp, typename enable_if<is_array<_Tp>::value, int>::type = 0>
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX17
void __destroy_at(_Tp* __loc) {
_LIBCPP_ASSERT(__loc != nullptr, "null pointer given to destroy_at");
_VSTD::__destroy(_VSTD::begin(*__loc), _VSTD::end(*__loc));
}
#endif
template <class _ForwardIterator>
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX17
_ForwardIterator __destroy(_ForwardIterator __first, _ForwardIterator __last) {
for (; __first != __last; ++__first)
_VSTD::__destroy_at(_VSTD::addressof(*__first));
return __first;
}
#if _LIBCPP_STD_VER > 14
template <class _Tp, enable_if_t<!is_array_v<_Tp>, int> = 0>
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX17
void destroy_at(_Tp* __loc) {
_VSTD::__destroy_at(__loc);
}
#if _LIBCPP_STD_VER > 17
template <class _Tp, enable_if_t<is_array_v<_Tp>, int> = 0>
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX17
void destroy_at(_Tp* __loc) {
_VSTD::__destroy_at(__loc);
}
#endif
template <class _ForwardIterator>
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX17
void destroy(_ForwardIterator __first, _ForwardIterator __last) {
(void)_VSTD::__destroy(_VSTD::move(__first), _VSTD::move(__last));
}
template <class _ForwardIterator, class _Size>
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_AFTER_CXX17
_ForwardIterator destroy_n(_ForwardIterator __first, _Size __n) {
for (; __n > 0; (void)++__first, --__n)
_VSTD::__destroy_at(_VSTD::addressof(*__first));
return __first;
}
#endif // _LIBCPP_STD_VER > 14
_LIBCPP_END_NAMESPACE_STD
#endif // _LIBCPP___MEMORY_CONSTRUCT_AT_H
|
