| //===----------------------------------------------------------------------===// |
| // |
| // 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___TYPE_TRAITS_ALIGNED_UNION_H |
| #define _LIBCPP___TYPE_TRAITS_ALIGNED_UNION_H |
| |
| #include <__config> |
| #include <__type_traits/aligned_storage.h> |
| #include <__type_traits/integral_constant.h> |
| #include <cstddef> |
| |
| #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) |
| # pragma GCC system_header |
| #endif |
| |
| _LIBCPP_BEGIN_NAMESPACE_STD |
| |
| template <size_t _I0, size_t ..._In> |
| struct __static_max; |
| |
| template <size_t _I0> |
| struct __static_max<_I0> |
| { |
| static const size_t value = _I0; |
| }; |
| |
| template <size_t _I0, size_t _I1, size_t ..._In> |
| struct __static_max<_I0, _I1, _In...> |
| { |
| static const size_t value = _I0 >= _I1 ? __static_max<_I0, _In...>::value : |
| __static_max<_I1, _In...>::value; |
| }; |
| |
| template <size_t _Len, class _Type0, class ..._Types> |
| struct aligned_union |
| { |
| static const size_t alignment_value = __static_max<_LIBCPP_PREFERRED_ALIGNOF(_Type0), |
| _LIBCPP_PREFERRED_ALIGNOF(_Types)...>::value; |
| static const size_t __len = __static_max<_Len, sizeof(_Type0), |
| sizeof(_Types)...>::value; |
| typedef typename aligned_storage<__len, alignment_value>::type type; |
| }; |
| |
| #if _LIBCPP_STD_VER > 11 |
| template <size_t _Len, class ..._Types> using aligned_union_t = typename aligned_union<_Len, _Types...>::type; |
| #endif |
| |
| _LIBCPP_END_NAMESPACE_STD |
| |
| #endif // _LIBCPP___TYPE_TRAITS_ALIGNED_UNION_H |
