1 | //===----------------------------------------------------------------------===// |
2 | // |
3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
4 | // See https://llvm.org/LICENSE.txt for license information. |
5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
6 | // |
7 | //===----------------------------------------------------------------------===// |
8 | |
9 | // UNSUPPORTED: c++03, c++11, c++14, c++17, c++20 |
10 | |
11 | // <mdspan> |
12 | |
13 | // template<class OtherExtents> |
14 | // constexpr explicit(!is_convertible_v<OtherExtents, extents_type>) |
15 | // mapping(const mapping<OtherExtents>&) noexcept; |
16 | |
17 | // Constraints: is_constructible_v<extents_type, OtherExtents> is true. |
18 | // |
19 | // Preconditions: other.required_span_size() is representable as a value of type index_type |
20 | |
21 | #include <mdspan> |
22 | #include <type_traits> |
23 | #include <cassert> |
24 | #include <limits> |
25 | |
26 | #include "test_macros.h" |
27 | |
28 | template <class To, class From> |
29 | constexpr void test_implicit_conversion(To dest, From src) { |
30 | assert(dest == src); |
31 | } |
32 | |
33 | template <bool implicit, class ToE, class FromE> |
34 | constexpr void test_conversion(FromE src_exts) { |
35 | using To = std::layout_right::mapping<ToE>; |
36 | using From = std::layout_right::mapping<FromE>; |
37 | From src(src_exts); |
38 | |
39 | ASSERT_NOEXCEPT(To(src)); |
40 | To dest(src); |
41 | |
42 | assert(dest == src); |
43 | if constexpr (implicit) { |
44 | dest = src; |
45 | assert(dest == src); |
46 | test_implicit_conversion<To, From>(src, src); |
47 | } |
48 | } |
49 | |
50 | template <class T1, class T2> |
51 | constexpr void test_conversion() { |
52 | constexpr size_t D = std::dynamic_extent; |
53 | constexpr bool idx_convertible = |
54 | static_cast<size_t>(std::numeric_limits<T1>::max()) >= static_cast<size_t>(std::numeric_limits<T2>::max()); |
55 | |
56 | // clang-format off |
57 | test_conversion<idx_convertible && true, std::extents<T1>>(std::extents<T2>()); |
58 | test_conversion<idx_convertible && true, std::extents<T1, D>>(std::extents<T2, D>(5)); |
59 | test_conversion<idx_convertible && false, std::extents<T1, 5>>(std::extents<T2, D>(5)); |
60 | test_conversion<idx_convertible && true, std::extents<T1, 5>>(std::extents<T2, 5>()); |
61 | test_conversion<idx_convertible && false, std::extents<T1, 5, D>>(std::extents<T2, D, D>(5, 5)); |
62 | test_conversion<idx_convertible && true, std::extents<T1, D, D>>(std::extents<T2, D, D>(5, 5)); |
63 | test_conversion<idx_convertible && true, std::extents<T1, D, D>>(std::extents<T2, D, 7>(5)); |
64 | test_conversion<idx_convertible && true, std::extents<T1, 5, 7>>(std::extents<T2, 5, 7>()); |
65 | test_conversion<idx_convertible && false, std::extents<T1, 5, D, 8, D, D>>(std::extents<T2, D, D, 8, 9, 1>(5, 7)); |
66 | test_conversion<idx_convertible && true, std::extents<T1, D, D, D, D, D>>( |
67 | std::extents<T2, D, D, D, D, D>(5, 7, 8, 9, 1)); |
68 | test_conversion<idx_convertible && true, std::extents<T1, D, D, 8, 9, D>>(std::extents<T2, D, 7, 8, 9, 1>(5)); |
69 | test_conversion<idx_convertible && true, std::extents<T1, 5, 7, 8, 9, 1>>(std::extents<T2, 5, 7, 8, 9, 1>()); |
70 | // clang-format on |
71 | } |
72 | |
73 | template <class IdxT, size_t... Extents> |
74 | using mapping_t = std::layout_right::mapping<std::extents<IdxT, Extents...>>; |
75 | |
76 | constexpr void test_no_implicit_conversion() { |
77 | constexpr size_t D = std::dynamic_extent; |
78 | |
79 | // Sanity check that one static to dynamic conversion works |
80 | static_assert(std::is_constructible_v<mapping_t<int, D>, mapping_t<int, 5>>); |
81 | static_assert(std::is_convertible_v<mapping_t<int, 5>, mapping_t<int, D>>); |
82 | |
83 | // Check that dynamic to static conversion only works explicitly |
84 | static_assert(std::is_constructible_v<mapping_t<int, 5>, mapping_t<int, D>>); |
85 | static_assert(!std::is_convertible_v<mapping_t<int, D>, mapping_t<int, 5>>); |
86 | |
87 | // Sanity check that one static to dynamic conversion works |
88 | static_assert(std::is_constructible_v<mapping_t<int, D, 7>, mapping_t<int, 5, 7>>); |
89 | static_assert(std::is_convertible_v<mapping_t<int, 5, 7>, mapping_t<int, D, 7>>); |
90 | |
91 | // Check that dynamic to static conversion only works explicitly |
92 | static_assert(std::is_constructible_v<mapping_t<int, 5, 7>, mapping_t<int, D, 7>>); |
93 | static_assert(!std::is_convertible_v<mapping_t<int, D, 7>, mapping_t<int, 5, 7>>); |
94 | |
95 | // Sanity check that smaller index_type to larger index_type conversion works |
96 | static_assert(std::is_constructible_v<mapping_t<size_t, 5>, mapping_t<int, 5>>); |
97 | static_assert(std::is_convertible_v<mapping_t<int, 5>, mapping_t<size_t, 5>>); |
98 | |
99 | // Check that larger index_type to smaller index_type conversion works explicitly only |
100 | static_assert(std::is_constructible_v<mapping_t<int, 5>, mapping_t<size_t, 5>>); |
101 | static_assert(!std::is_convertible_v<mapping_t<size_t, 5>, mapping_t<int, 5>>); |
102 | } |
103 | |
104 | constexpr void test_rank_mismatch() { |
105 | constexpr size_t D = std::dynamic_extent; |
106 | |
107 | static_assert(!std::is_constructible_v<mapping_t<int, D>, mapping_t<int>>); |
108 | static_assert(!std::is_constructible_v<mapping_t<int>, mapping_t<int, D, D>>); |
109 | static_assert(!std::is_constructible_v<mapping_t<int, D>, mapping_t<int, D, D>>); |
110 | static_assert(!std::is_constructible_v<mapping_t<int, D, D, D>, mapping_t<int, D, D>>); |
111 | } |
112 | |
113 | constexpr void test_static_extent_mismatch() { |
114 | constexpr size_t D = std::dynamic_extent; |
115 | |
116 | static_assert(!std::is_constructible_v<mapping_t<int, D, 5>, mapping_t<int, D, 4>>); |
117 | static_assert(!std::is_constructible_v<mapping_t<int, 5>, mapping_t<int, 4>>); |
118 | static_assert(!std::is_constructible_v<mapping_t<int, 5, D>, mapping_t<int, 4, D>>); |
119 | } |
120 | |
121 | constexpr bool test() { |
122 | test_conversion<int, int>(); |
123 | test_conversion<int, size_t>(); |
124 | test_conversion<size_t, int>(); |
125 | test_conversion<size_t, long>(); |
126 | test_no_implicit_conversion(); |
127 | test_rank_mismatch(); |
128 | test_static_extent_mismatch(); |
129 | return true; |
130 | } |
131 | |
132 | int main(int, char**) { |
133 | test(); |
134 | static_assert(test()); |
135 | return 0; |
136 | } |
137 | |