llvm-project/libcxx/include/experimental/__memory

90 lines
2.7 KiB
C++

// -*- 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_EXPERIMENTAL___MEMORY
#define _LIBCPP_EXPERIMENTAL___MEMORY
#include <experimental/__config>
#include <experimental/utility> // for erased_type
#include <__functional_base>
#include <type_traits>
_LIBCPP_BEGIN_NAMESPACE_LFTS
template <
class _Tp, class _Alloc
, bool = uses_allocator<_Tp, _Alloc>::value
, bool = __has_allocator_type<_Tp>::value
>
struct __lfts_uses_allocator : public false_type {};
template <class _Tp, class _Alloc>
struct __lfts_uses_allocator<_Tp, _Alloc, false, false> : public false_type {};
template <class _Tp, class _Alloc, bool HasAlloc>
struct __lfts_uses_allocator<_Tp, _Alloc, true, HasAlloc> : public true_type {};
template <class _Tp, class _Alloc>
struct __lfts_uses_allocator<_Tp, _Alloc, false, true>
: public integral_constant<bool
, is_convertible<_Alloc, typename _Tp::allocator_type>::value
|| is_same<erased_type, typename _Tp::allocator_type>::value
>
{};
template <bool _UsesAlloc, class _Tp, class _Alloc, class ..._Args>
struct __lfts_uses_alloc_ctor_imp
{
static const int value = 0;
};
template <class _Tp, class _Alloc, class ..._Args>
struct __lfts_uses_alloc_ctor_imp<true, _Tp, _Alloc, _Args...>
{
static const bool __ic_first
= is_constructible<_Tp, allocator_arg_t, _Alloc, _Args...>::value;
static const bool __ic_second =
conditional<
__ic_first,
false_type,
is_constructible<_Tp, _Args..., _Alloc>
>::type::value;
static_assert(__ic_first || __ic_second,
"Request for uses allocator construction is ill-formed");
static const int value = __ic_first ? 1 : 2;
};
template <class _Tp, class _Alloc, class ..._Args>
struct __lfts_uses_alloc_ctor
: integral_constant<int,
__lfts_uses_alloc_ctor_imp<
__lfts_uses_allocator<_Tp, _Alloc>::value
, _Tp, _Alloc, _Args...
>::value
>
{};
template <class _Tp, class _Alloc, class ..._Args>
inline _LIBCPP_INLINE_VISIBILITY
void __lfts_user_alloc_construct(
_Tp * __store, const _Alloc & __a, _Args &&... __args)
{
_VSTD::__user_alloc_construct_impl(
typename __lfts_uses_alloc_ctor<_Tp, _Alloc, _Args...>::type()
, __store, __a, _VSTD::forward<_Args>(__args)...
);
}
_LIBCPP_END_NAMESPACE_LFTS
#endif /* _LIBCPP_EXPERIMENTAL___MEMORY */