mirror of
https://codeberg.org/ziglang/zig.git
synced 2026-04-26 13:01:34 +03:00
Alex Rønne Petersen
104 lines
3.6 KiB
C++
Vendored
104 lines
3.6 KiB
C++
Vendored
//===----------------------------------------------------------------------===//
|
|
//
|
|
// 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___ATOMIC_ATOMIC_WAITABLE_TRAITS_H
|
|
#define _LIBCPP___ATOMIC_ATOMIC_WAITABLE_TRAITS_H
|
|
|
|
#include <__atomic/contention_t.h>
|
|
#include <__atomic/memory_order.h>
|
|
#include <__config>
|
|
#include <__type_traits/decay.h>
|
|
#include <__type_traits/has_unique_object_representation.h>
|
|
#include <__type_traits/is_same.h>
|
|
#include <__type_traits/is_trivially_copyable.h>
|
|
#include <__type_traits/void_t.h>
|
|
#include <__utility/declval.h>
|
|
#include <cstring>
|
|
|
|
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
|
|
# pragma GCC system_header
|
|
#endif
|
|
|
|
_LIBCPP_BEGIN_NAMESPACE_STD
|
|
|
|
#if _LIBCPP_STD_VER >= 20
|
|
|
|
// The customisation points to enable the following functions:
|
|
// - __atomic_wait
|
|
// - __atomic_wait_unless
|
|
// - __atomic_notify_one
|
|
// - __atomic_notify_all
|
|
template <class _Tp, class = void>
|
|
struct __atomic_waitable_traits {
|
|
using __value_type _LIBCPP_NODEBUG = void;
|
|
|
|
template <class _AtomicWaitable>
|
|
static void __atomic_load(_AtomicWaitable&&, memory_order) = delete;
|
|
|
|
template <class _AtomicWaitable>
|
|
static void __atomic_contention_address(_AtomicWaitable&&) = delete;
|
|
};
|
|
|
|
template <class _Tp>
|
|
concept __atomic_waitable = requires(const _Tp __t, memory_order __order) {
|
|
typename __atomic_waitable_traits<__decay_t<_Tp> >::__value_type;
|
|
{ __atomic_waitable_traits<__decay_t<_Tp> >::__atomic_load(__t, __order) };
|
|
{ __atomic_waitable_traits<__decay_t<_Tp> >::__atomic_contention_address(__t) };
|
|
};
|
|
|
|
# ifdef __linux__
|
|
# define _LIBCPP_NATIVE_PLATFORM_WAIT_SIZES(_APPLY) _APPLY(4)
|
|
# elif defined(__APPLE__)
|
|
# define _LIBCPP_NATIVE_PLATFORM_WAIT_SIZES(_APPLY) \
|
|
_APPLY(4) \
|
|
_APPLY(8)
|
|
# elif defined(__FreeBSD__) && __SIZEOF_LONG__ == 8
|
|
# define _LIBCPP_NATIVE_PLATFORM_WAIT_SIZES(_APPLY) _APPLY(8)
|
|
# elif defined(_WIN32)
|
|
# define _LIBCPP_NATIVE_PLATFORM_WAIT_SIZES(_APPLY) _APPLY(8)
|
|
# else
|
|
# define _LIBCPP_NATIVE_PLATFORM_WAIT_SIZES(_APPLY) _APPLY(sizeof(__cxx_contention_t))
|
|
# endif // __linux__
|
|
|
|
// concepts defines the types are supported natively by the platform's wait
|
|
|
|
# if defined(_LIBCPP_ABI_ATOMIC_WAIT_NATIVE_BY_SIZE)
|
|
|
|
template <class _Tp>
|
|
_LIBCPP_HIDE_FROM_ABI constexpr bool __has_native_atomic_wait_impl() {
|
|
if (alignof(_Tp) % sizeof(_Tp) != 0)
|
|
return false;
|
|
switch (sizeof(_Tp)) {
|
|
# define _LIBCPP_MAKE_CASE(n) \
|
|
case n: \
|
|
return true;
|
|
_LIBCPP_NATIVE_PLATFORM_WAIT_SIZES(_LIBCPP_MAKE_CASE)
|
|
default:
|
|
return false;
|
|
# undef _LIBCPP_MAKE_CASE
|
|
};
|
|
}
|
|
|
|
template <class _Tp>
|
|
concept __has_native_atomic_wait =
|
|
has_unique_object_representations_v<_Tp> && is_trivially_copyable_v<_Tp> &&
|
|
std::__has_native_atomic_wait_impl<_Tp>();
|
|
|
|
# else // _LIBCPP_ABI_ATOMIC_WAIT_NATIVE_BY_SIZE
|
|
|
|
template <class _Tp>
|
|
concept __has_native_atomic_wait = is_same_v<_Tp, __cxx_contention_t>;
|
|
|
|
# endif // _LIBCPP_ABI_ATOMIC_WAIT_NATIVE_BY_SIZE
|
|
|
|
#endif // C++20
|
|
|
|
_LIBCPP_END_NAMESPACE_STD
|
|
|
|
#endif // _LIBCPP___ATOMIC_ATOMIC_WAITABLE_TRAITS_H
|