77 lines · cpp
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-exception6//7//===----------------------------------------------------------------------===//8// UNSUPPORTED: c++03, c++11, c++14, c++179 10// <span>11 12// template <class ElementType, size_t Extent>13// span<byte,14// Extent == dynamic_extent15// ? dynamic_extent16// : sizeof(ElementType) * Extent>17// as_writable_bytes(span<ElementType, Extent> s) noexcept;18 19#include <cassert>20#include <cstddef>21#include <span>22#include <string>23 24#include "test_macros.h"25 26template <typename Span>27void testRuntimeSpan(Span sp) {28 ASSERT_NOEXCEPT(std::as_writable_bytes(sp));29 30 auto spBytes = std::as_writable_bytes(sp);31 using SB = decltype(spBytes);32 ASSERT_SAME_TYPE(std::byte, typename SB::element_type);33 34 if constexpr (sp.extent == std::dynamic_extent)35 assert(spBytes.extent == std::dynamic_extent);36 else37 assert(spBytes.extent == sizeof(typename Span::element_type) * sp.extent);38 39 assert(static_cast<void*>(spBytes.data()) == static_cast<void*>(sp.data()));40 assert(spBytes.size() == sp.size_bytes());41}42 43struct A {};44int iArr2[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9};45 46int main(int, char**) {47 testRuntimeSpan(std::span<int>());48 testRuntimeSpan(std::span<long>());49 testRuntimeSpan(std::span<double>());50 testRuntimeSpan(std::span<A>());51 testRuntimeSpan(std::span<std::string>());52 53 testRuntimeSpan(std::span<int, 0>());54 testRuntimeSpan(std::span<long, 0>());55 testRuntimeSpan(std::span<double, 0>());56 testRuntimeSpan(std::span<A, 0>());57 testRuntimeSpan(std::span<std::string, 0>());58 59 testRuntimeSpan(std::span<int>(iArr2, 1));60 testRuntimeSpan(std::span<int>(iArr2, 2));61 testRuntimeSpan(std::span<int>(iArr2, 3));62 testRuntimeSpan(std::span<int>(iArr2, 4));63 testRuntimeSpan(std::span<int>(iArr2, 5));64 65 testRuntimeSpan(std::span<int, 1>(iArr2 + 5, 1));66 testRuntimeSpan(std::span<int, 2>(iArr2 + 4, 2));67 testRuntimeSpan(std::span<int, 3>(iArr2 + 3, 3));68 testRuntimeSpan(std::span<int, 4>(iArr2 + 2, 4));69 testRuntimeSpan(std::span<int, 5>(iArr2 + 1, 5));70 71 std::string s;72 testRuntimeSpan(std::span<std::string>(&s, (std::size_t)0));73 testRuntimeSpan(std::span<std::string>(&s, 1));74 75 return 0;76}77