1 // -*- C++ -*- 2 //===----------------------------------------------------------------------===// 3 // 4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 5 // See https://llvm.org/LICENSE.txt for license information. 6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 7 // 8 // Kokkos v. 4.0 9 // Copyright (2022) National Technology & Engineering 10 // Solutions of Sandia, LLC (NTESS). 11 // 12 // Under the terms of Contract DE-NA0003525 with NTESS, 13 // the U.S. Government retains certain rights in this software. 14 // 15 //===---------------------------------------------------------------------===// 16 17 #ifndef _LIBCPP___MDSPAN_DEFAULT_ACCESSOR_H 18 #define _LIBCPP___MDSPAN_DEFAULT_ACCESSOR_H 19 20 #include <__config> 21 #include <__cstddef/size_t.h> 22 #include <__type_traits/is_abstract.h> 23 #include <__type_traits/is_array.h> 24 #include <__type_traits/is_convertible.h> 25 #include <__type_traits/remove_const.h> 26 27 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 28 # pragma GCC system_header 29 #endif 30 31 _LIBCPP_PUSH_MACROS 32 #include <__undef_macros> 33 34 _LIBCPP_BEGIN_NAMESPACE_STD 35 36 #if _LIBCPP_STD_VER >= 23 37 38 template <class _ElementType> 39 struct default_accessor { 40 static_assert(!is_array_v<_ElementType>, "default_accessor: template argument may not be an array type"); 41 static_assert(!is_abstract_v<_ElementType>, "default_accessor: template argument may not be an abstract class"); 42 43 using offset_policy = default_accessor; 44 using element_type = _ElementType; 45 using reference = _ElementType&; 46 using data_handle_type = _ElementType*; 47 48 _LIBCPP_HIDE_FROM_ABI constexpr default_accessor() noexcept = default; 49 template <class _OtherElementType> 50 requires(is_convertible_v<_OtherElementType (*)[], element_type (*)[]>) 51 _LIBCPP_HIDE_FROM_ABI constexpr default_accessor(default_accessor<_OtherElementType>) noexcept {} 52 53 _LIBCPP_HIDE_FROM_ABI constexpr reference access(data_handle_type __p, size_t __i) const noexcept { return __p[__i]; } 54 _LIBCPP_HIDE_FROM_ABI constexpr data_handle_type offset(data_handle_type __p, size_t __i) const noexcept { 55 return __p + __i; 56 } 57 }; 58 59 #endif // _LIBCPP_STD_VER >= 23 60 61 _LIBCPP_END_NAMESPACE_STD 62 63 _LIBCPP_POP_MACROS 64 65 #endif // _LIBCPP___MDSPAN_DEFAULT_ACCESSOR_H 66