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 // UNSUPPORTED: c++03, c++11, c++14, c++17
9
10 // <span>
11
12 // constexpr size_type size_bytes() const noexcept;
13 //
14 // Effects: Equivalent to: return size() * sizeof(element_type);
15
16
17 #include <span>
18 #include <cassert>
19 #include <string>
20
21 #include "test_macros.h"
22
23
24 template <typename Span>
testConstexprSpan(Span sp,std::size_t sz)25 constexpr bool testConstexprSpan(Span sp, std::size_t sz)
26 {
27 ASSERT_NOEXCEPT(sp.size_bytes());
28 return (std::size_t) sp.size_bytes() == sz * sizeof(typename Span::element_type);
29 }
30
31
32 template <typename Span>
testRuntimeSpan(Span sp,std::size_t sz)33 void testRuntimeSpan(Span sp, std::size_t sz)
34 {
35 ASSERT_NOEXCEPT(sp.size_bytes());
36 assert((std::size_t) sp.size_bytes() == sz * sizeof(typename Span::element_type));
37 }
38
39 struct A{};
40 constexpr int iArr1[] = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9};
41 int iArr2[] = {10, 11, 12, 13, 14, 15, 16, 17, 18, 19};
42
main(int,char **)43 int main(int, char**)
44 {
45 static_assert(testConstexprSpan(std::span<int>(), 0), "");
46 static_assert(testConstexprSpan(std::span<long>(), 0), "");
47 static_assert(testConstexprSpan(std::span<double>(), 0), "");
48 static_assert(testConstexprSpan(std::span<A>(), 0), "");
49 static_assert(testConstexprSpan(std::span<std::string>(), 0), "");
50
51 static_assert(testConstexprSpan(std::span<int, 0>(), 0), "");
52 static_assert(testConstexprSpan(std::span<long, 0>(), 0), "");
53 static_assert(testConstexprSpan(std::span<double, 0>(), 0), "");
54 static_assert(testConstexprSpan(std::span<A, 0>(), 0), "");
55 static_assert(testConstexprSpan(std::span<std::string, 0>(), 0), "");
56
57 static_assert(testConstexprSpan(std::span<const int>(iArr1, 1), 1), "");
58 static_assert(testConstexprSpan(std::span<const int>(iArr1, 2), 2), "");
59 static_assert(testConstexprSpan(std::span<const int>(iArr1, 3), 3), "");
60 static_assert(testConstexprSpan(std::span<const int>(iArr1, 4), 4), "");
61 static_assert(testConstexprSpan(std::span<const int>(iArr1, 5), 5), "");
62
63 testRuntimeSpan(std::span<int> (), 0);
64 testRuntimeSpan(std::span<long> (), 0);
65 testRuntimeSpan(std::span<double> (), 0);
66 testRuntimeSpan(std::span<A> (), 0);
67 testRuntimeSpan(std::span<std::string>(), 0);
68
69 testRuntimeSpan(std::span<int, 0> (), 0);
70 testRuntimeSpan(std::span<long, 0> (), 0);
71 testRuntimeSpan(std::span<double, 0> (), 0);
72 testRuntimeSpan(std::span<A, 0> (), 0);
73 testRuntimeSpan(std::span<std::string, 0>(), 0);
74
75 testRuntimeSpan(std::span<int>(iArr2, 1), 1);
76 testRuntimeSpan(std::span<int>(iArr2, 2), 2);
77 testRuntimeSpan(std::span<int>(iArr2, 3), 3);
78 testRuntimeSpan(std::span<int>(iArr2, 4), 4);
79 testRuntimeSpan(std::span<int>(iArr2, 5), 5);
80
81 testRuntimeSpan(std::span<int, 1>(iArr2 + 5, 1), 1);
82 testRuntimeSpan(std::span<int, 2>(iArr2 + 4, 2), 2);
83 testRuntimeSpan(std::span<int, 3>(iArr2 + 3, 3), 3);
84 testRuntimeSpan(std::span<int, 4>(iArr2 + 2, 4), 4);
85 testRuntimeSpan(std::span<int, 5>(iArr2 + 1, 5), 5);
86
87 std::string s;
88 testRuntimeSpan(std::span<std::string>(&s, (std::size_t) 0), 0);
89 testRuntimeSpan(std::span<std::string>(&s, 1), 1);
90
91 return 0;
92 }
93