| //===----------------------------------------------------------------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| |
| // REQUIRES: has-unix-headers |
| // UNSUPPORTED: c++03, c++11, c++14, c++17, c++20 |
| // UNSUPPORTED: libcpp-hardening-mode=none |
| // XFAIL: availability-verbose_abort-missing |
| |
| // <mdspan> |
| |
| // template<class StridedLayoutMapping> |
| // constexpr explicit(see below) |
| // mapping(const StridedLayoutMapping& other) noexcept; |
| // |
| // Constraints: |
| // - layout-mapping-alike<StridedLayoutMapping> is satisfied. |
| // - is_constructible_v<extents_type, typename StridedLayoutMapping::extents_type> is true. |
| // - StridedLayoutMapping::is_always_unique() is true. |
| // - StridedLayoutMapping::is_always_strided() is true. |
| // |
| // Preconditions: |
| // - StridedLayoutMapping meets the layout mapping requirements ([mdspan.layout.policy.reqmts]), |
| // - other.stride(r) > 0 is true for every rank index r of extents(), |
| // - other.required_span_size() is representable as a value of type index_type ([basic.fundamental]), and |
| // - OFFSET(other) == 0 is true. |
| // |
| // Effects: Direct-non-list-initializes extents_ with other.extents(), and for all d in the range [0, rank_), |
| // direct-non-list-initializes strides_[d] with other.stride(d). |
| // |
| // Remarks: The expression inside explicit is equivalent to: |
| // - !(is_convertible_v<typename StridedLayoutMapping::extents_type, extents_type> && |
| // (is-mapping-of<layout_left, LayoutStrideMapping> || |
| // is-mapping-of<layout_right, LayoutStrideMapping> || |
| // is-mapping-of<layout_stride, LayoutStrideMapping>)) |
| |
| #include <mdspan> |
| #include <cassert> |
| |
| #include "check_assertion.h" |
| #include "../../../../../std/containers/views/mdspan/CustomTestLayouts.h" |
| |
| int main(int, char**) { |
| constexpr size_t D = std::dynamic_extent; |
| |
| // working case |
| { |
| std::extents<int, D, D> arg_exts{100, 5}; |
| std::layout_stride::mapping<std::extents<int, D, D>> arg(arg_exts, std::array<int, 2>{1, 100}); |
| [[maybe_unused]] std::layout_stride::mapping<std::extents<size_t, D, 5>> m(arg); // should work |
| } |
| // mismatch of static extent |
| { |
| std::extents<int, D, D> arg_exts{100, 5}; |
| std::layout_stride::mapping<std::extents<int, D, D>> arg(arg_exts, std::array<int, 2>{1, 100}); |
| TEST_LIBCPP_ASSERT_FAILURE(([=] { std::layout_stride::mapping<std::extents<int, D, 3>> m(arg); }()), |
| "extents construction: mismatch of provided arguments with static extents."); |
| } |
| // non-representability of extents itself |
| { |
| TEST_LIBCPP_ASSERT_FAILURE( |
| ([=] { |
| std::layout_stride::mapping<std::extents<char, D>> m( |
| std::layout_stride::mapping<std::extents<int, D>>(std::extents<int, D>(500), std::array<int, 1>{1})); |
| }()), |
| "extents ctor: arguments must be representable as index_type and nonnegative"); |
| } |
| // all strides must be larger than zero |
| { |
| always_convertible_layout::mapping<std::dextents<int, 2>> offset_map(std::dextents<int, 2>{10, 10}, 100, -1); |
| TEST_LIBCPP_ASSERT_FAILURE( |
| ([=] { std::layout_stride::template mapping<std::extents<char, D, D>> m(offset_map); }()), |
| "layout_stride::mapping converting ctor: all strides must be greater than 0"); |
| } |
| // required_span_size not representable, while individual extents are |
| { |
| std::extents<int, D, D> arg_exts{100, 5}; |
| std::layout_stride::mapping<std::extents<int, D, D>> arg(arg_exts, std::array<int, 2>{1, 100}); |
| // check extents would be constructible |
| [[maybe_unused]] std::extents<char, D, 5> e(arg_exts); |
| // but the product is not, so we can't use it for layout_stride |
| TEST_LIBCPP_ASSERT_FAILURE( |
| ([=] { std::layout_stride::template mapping<std::extents<char, D, 5>> m(arg); }()), |
| "layout_stride::mapping converting ctor: other.required_span_size() must be representable as index_type."); |
| } |
| // required_span_size not representable, while individual extents are, edge case |
| { |
| // required span size = (3-1)*50 + (10-1) * 3 + 1 = 128 |
| std::extents<int, D, D> arg_exts{3, 10}; |
| std::layout_stride::mapping<std::extents<int, D, D>> arg(arg_exts, std::array<int, 2>{50, 3}); |
| // sanity check: |
| assert(arg.required_span_size() == 128); |
| // check extents would be constructible |
| [[maybe_unused]] std::extents<signed char, D, 10> e(arg_exts); |
| // but the product is not, so we can't use it for layout_stride |
| TEST_LIBCPP_ASSERT_FAILURE( |
| ([=] { std::layout_stride::template mapping<std::extents<signed char, D, 10>> m(arg); }()), |
| "layout_stride::mapping converting ctor: other.required_span_size() must be representable as index_type."); |
| } |
| // base offset must be 0 (i.e. mapping(0,...,0)==0) for a strided layout with positive strides |
| { |
| always_convertible_layout::mapping<std::dextents<int, 2>> offset_map(std::dextents<int, 2>{10, 10}, 3); |
| TEST_LIBCPP_ASSERT_FAILURE( |
| ([=] { std::layout_stride::template mapping<std::extents<char, D, D>> m(offset_map); }()), |
| "layout_stride::mapping converting ctor: base offset of mapping must be zero."); |
| } |
| return 0; |
| } |