1bdd1243dSDimitry Andric //===----------------------------------------------------------------------===// 2bdd1243dSDimitry Andric // 3bdd1243dSDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4bdd1243dSDimitry Andric // See https://llvm.org/LICENSE.txt for license information. 5bdd1243dSDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6bdd1243dSDimitry Andric // 7bdd1243dSDimitry Andric //===----------------------------------------------------------------------===// 8bdd1243dSDimitry Andric 9bdd1243dSDimitry Andric #ifndef _LIBCPP___MEMORY_TEMP_VALUE_H 10bdd1243dSDimitry Andric #define _LIBCPP___MEMORY_TEMP_VALUE_H 11bdd1243dSDimitry Andric 12bdd1243dSDimitry Andric #include <__config> 13bdd1243dSDimitry Andric #include <__memory/addressof.h> 14bdd1243dSDimitry Andric #include <__memory/allocator_traits.h> 15bdd1243dSDimitry Andric #include <__type_traits/aligned_storage.h> 16bdd1243dSDimitry Andric #include <__utility/forward.h> 17bdd1243dSDimitry Andric 18bdd1243dSDimitry Andric #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 19bdd1243dSDimitry Andric # pragma GCC system_header 20bdd1243dSDimitry Andric #endif 21bdd1243dSDimitry Andric 22bdd1243dSDimitry Andric _LIBCPP_BEGIN_NAMESPACE_STD 23bdd1243dSDimitry Andric 24bdd1243dSDimitry Andric template <class _Tp, class _Alloc> 25bdd1243dSDimitry Andric struct __temp_value { 26bdd1243dSDimitry Andric typedef allocator_traits<_Alloc> _Traits; 27bdd1243dSDimitry Andric 28bdd1243dSDimitry Andric #ifdef _LIBCPP_CXX03_LANG 29bdd1243dSDimitry Andric typename aligned_storage<sizeof(_Tp), _LIBCPP_ALIGNOF(_Tp)>::type __v; 30bdd1243dSDimitry Andric #else 31*cb14a3feSDimitry Andric union { 32*cb14a3feSDimitry Andric _Tp __v; 33*cb14a3feSDimitry Andric }; 34bdd1243dSDimitry Andric #endif 35bdd1243dSDimitry Andric _Alloc& __a; 36bdd1243dSDimitry Andric 3706c3fb27SDimitry Andric _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp* __addr() { 38bdd1243dSDimitry Andric #ifdef _LIBCPP_CXX03_LANG 39bdd1243dSDimitry Andric return reinterpret_cast<_Tp*>(std::addressof(__v)); 40bdd1243dSDimitry Andric #else 41bdd1243dSDimitry Andric return std::addressof(__v); 42bdd1243dSDimitry Andric #endif 43bdd1243dSDimitry Andric } 44bdd1243dSDimitry Andric 4506c3fb27SDimitry Andric _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _Tp& get() { return *__addr(); } 46bdd1243dSDimitry Andric 47bdd1243dSDimitry Andric template <class... _Args> 48*cb14a3feSDimitry Andric _LIBCPP_HIDE_FROM_ABI _LIBCPP_NO_CFI _LIBCPP_CONSTEXPR_SINCE_CXX20 __temp_value(_Alloc& __alloc, _Args&&... __args) 49*cb14a3feSDimitry Andric : __a(__alloc) { 50bdd1243dSDimitry Andric _Traits::construct(__a, __addr(), std::forward<_Args>(__args)...); 51bdd1243dSDimitry Andric } 52bdd1243dSDimitry Andric 5306c3fb27SDimitry Andric _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 ~__temp_value() { _Traits::destroy(__a, __addr()); } 54bdd1243dSDimitry Andric }; 55bdd1243dSDimitry Andric 56bdd1243dSDimitry Andric _LIBCPP_END_NAMESPACE_STD 57bdd1243dSDimitry Andric 58bdd1243dSDimitry Andric #endif // _LIBCPP___MEMORY_TEMP_VALUE_H 59