53 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 9// UNSUPPORTED: c++03, c++11, c++14, c++17, c++2010 11// <mdspan>12 13// constexpr index_type stride(rank_type i) const noexcept;14//15// Constraints: extents_type::rank() > 0 is true.16//17// Preconditions: i < extents_type::rank() is true.18//19// Returns: extents().rev-prod-of-extents(i).20 21#include <mdspan>22#include <array>23#include <cassert>24#include <cstdint>25#include <cstdio>26 27#include "test_macros.h"28 29template <class E, class... Args>30constexpr void test_stride(std::array<typename E::index_type, E::rank()> strides, Args... args) {31 using M = std::layout_right::mapping<E>;32 M m(E(args...));33 34 ASSERT_NOEXCEPT(m.stride(0));35 for (size_t r = 0; r < E::rank(); r++)36 assert(strides[r] == m.stride(r));37}38 39constexpr bool test() {40 constexpr size_t D = std::dynamic_extent;41 test_stride<std::extents<unsigned, D>>(std::array<unsigned, 1>{1}, 7);42 test_stride<std::extents<unsigned, 7>>(std::array<unsigned, 1>{1});43 test_stride<std::extents<unsigned, 7, 8>>(std::array<unsigned, 2>{8, 1});44 test_stride<std::extents<int64_t, D, 8, D, D>>(std::array<int64_t, 4>{720, 90, 10, 1}, 7, 9, 10);45 return true;46}47 48int main(int, char**) {49 test();50 static_assert(test());51 return 0;52}53