On Wed, Jun 4, 2025 at 2:05 PM Luc Grosheintz <[email protected]>
wrote:
>
>
> On 6/4/25 13:19, Tomasz Kaminski wrote:
> > Ah, sorry I got confused in the review suggestions, and latter when
> > checking the code.
> > What I meant is:
> >
> > Because the incoming strided_layout is required to be unique,
> > that implies that for each of strides are greater or equal to the
> extents.
> > As a consequence, other.required_span_size() is always greater than equal
> > to size of index_space,
> > so we can have static assert like:
> > static_assert(__mdspan::__representable_size<_OExtents, index_type>,
> > "other.required_span_size() must be representable as index_type");
> > In here:
> > if constexpr (cmp_greater(
> > numeric_limits<typename
> _StridedMapping::index_type>::max(),
> > numeric_limits<index_type>::max()))
> > {
> > static_assert(__mdspan::__representable_size<_OExtents,
> > index_type>,
> > "other.required_span_size() must be representable as
> > index_type")
> >
> __glibcxx_assert(!cmp_less(numeric_limits<index_type>::max(),
> > __other.required_span_size()));
> > }
> >
>
> I would lift the static assertion above the `if constexpr` because
> that way we have to trust the other mapping less.
>
Sure, make sense.
>
> >
> >
> > On Wed, Jun 4, 2025 at 1:09 PM Luc Grosheintz <[email protected]>
> > wrote:
> >
> >>
> >>
> >> On 6/3/25 15:24, Tomasz Kaminski wrote:
> >>> On Fri, May 30, 2025 at 6:44 PM Luc Grosheintz <
> [email protected]
> >>>
> >>> wrote:
> >>>
> >>>> Implements the tests for layout_stride and for the features of the
> other
> >>>> two layouts that depend on layout_stride.
> >>>>
> >>>> libstdc++-v3/ChangeLog:
> >>>>
> >>>> *
> testsuite/23_containers/mdspan/layouts/class_mandate_neg.cc:
> >> Add
> >>>> tests for layout_stride.
> >>>> * testsuite/23_containers/mdspan/layouts/ctors.cc: Add test
> for
> >>>> layout_stride and the interaction with other layouts.
> >>>> * testsuite/23_containers/mdspan/layouts/mapping.cc: Ditto.
> >>>> * testsuite/23_containers/mdspan/layouts/stride.cc: New
> test.
> >>>>
> >>>> Signed-off-by: Luc Grosheintz <[email protected]>
> >>>> ---
> >>>>
> >>> LTGM. Only one comment regarding the tests that we could add.
> >>>
> >>>> .../mdspan/layouts/class_mandate_neg.cc | 3 +
> >>>> .../23_containers/mdspan/layouts/ctors.cc | 99 ++++
> >>>> .../23_containers/mdspan/layouts/empty.cc | 1 +
> >>>> .../23_containers/mdspan/layouts/mapping.cc | 75 ++-
> >>>> .../23_containers/mdspan/layouts/stride.cc | 526
> ++++++++++++++++++
> >>>> 5 files changed, 703 insertions(+), 1 deletion(-)
> >>>> create mode 100644
> >>>> libstdc++-v3/testsuite/23_containers/mdspan/layouts/stride.cc
> >>>>
> >>>> diff --git
> >>>>
> >>
> a/libstdc++-v3/testsuite/23_containers/mdspan/layouts/class_mandate_neg.cc
> >>>>
> >>
> b/libstdc++-v3/testsuite/23_containers/mdspan/layouts/class_mandate_neg.cc
> >>>> index 6469fa601e9..6862ed0c0ae 100644
> >>>> ---
> >>>>
> >>
> a/libstdc++-v3/testsuite/23_containers/mdspan/layouts/class_mandate_neg.cc
> >>>> +++
> >>>>
> >>
> b/libstdc++-v3/testsuite/23_containers/mdspan/layouts/class_mandate_neg.cc
> >>>> @@ -31,9 +31,12 @@ template<size_t Count, typename Layout, typename
> >>>> OLayout>
> >>>>
> >>>> A<std::layout_left> a_left; // { dg-error
> >> "required
> >>>> from" }
> >>>> A<std::layout_right> a_right; // { dg-error
> >> "required
> >>>> from" }
> >>>> +A<std::layout_stride> a_stride; // { dg-error
> >> "required
> >>>> from" }
> >>>>
> >>>> B<1, std::layout_left, std::layout_left> bll; // { dg-error
> >> "required
> >>>> here" }
> >>>> +B<2, std::layout_left, std::layout_stride> bls; // { dg-error
> >> "required
> >>>> here" }
> >>>>
> >>> With the message that we added to static assert to layout_stride
> >>> constructor:
> >>> >> "other.required_span_size() must be representable as
> index_type"
> >>> I believe you could add here:
> >>> B<2, std::layout_stride, std::layout_left>
> >>> And similarly for layout_right.
> >>
> >> I've tried (even before) and always failed miserably. Only good news
> >> is that the final
> >>
> >> // { dg-prune-output "must be representable as index_type" }
> >>
> >> isn't superfluous. I seem like the only string I can match against
> >> is the one associated with that line of code, in this case that's
> >>
> >> mdspan:773: error: static assertion failed: The size of OtherExtents
> >> must be representable as index_type
> >> [ ... ]
> >> class_mandate_neg.cc:40: note: synthesized method 'constexpr B<4,
> >> std::layout_right, std::layout_stride>::B()' first required here
> >>
> >> I unsure why you're saying that we added the message:
> >>
> >> "other.required_span_size() must be representable as index_type"
> >>
> >> to a static_assert, we added it to a __glibcxx_assert. The tests here
> >> are designed to trigger different assertions.
> >>
> >> "A" triggers:
> >>
> >> template<typename _Extents>
> >> class layout_*::mapping
> >> {
> >> public:
> >> // ...
> >>
> >> static_assert(__mdspan::__representable_size<extents_type,
> >> index_type>,
> >> "The size of extents_type must be representable as
> index_type");
> >>
> >>
> >> "B" triggers:
> >>
> >> template<typename _OExtents>
> >> constexpr explicit
> >> mapping(const _OExtents& __oexts, __mdspan::__internal_ctor)
> noexcept
> >> : _M_extents(__oexts)
> >> {
> >> static_assert(__mdspan::__representable_size<_OExtents,
> index_type>,
> >> "The size of OtherExtents must be representable as
> index_type");
> >>
> >> We don't have tests that make __glibcxx_assert's fail. We could probably
> >> do it with constexpr variables with "dynamic" extents.
> >>
> >>>
> >>>>
> >>>> B<3, std::layout_right, std::layout_right> brr; // { dg-error
> >> "required
> >>>> here" }
> >>>> +B<4, std::layout_right, std::layout_stride> brs; // { dg-error
> >> "required
> >>>> here" }
> >>>>
> >>>> // { dg-prune-output "must be representable as index_type" }
> >>>> diff --git
> >> a/libstdc++-v3/testsuite/23_containers/mdspan/layouts/ctors.cc
> >>>> b/libstdc++-v3/testsuite/23_containers/mdspan/layouts/ctors.cc
> >>>> index b0e03161874..695e887ca87 100644
> >>>> --- a/libstdc++-v3/testsuite/23_containers/mdspan/layouts/ctors.cc
> >>>> +++ b/libstdc++-v3/testsuite/23_containers/mdspan/layouts/ctors.cc
> >>>> @@ -323,6 +323,104 @@ namespace from_left_or_right
> >>>> }
> >>>> }
> >>>>
> >>>> +// ctor: mapping(layout_stride::mapping<OExtents>)
> >>>> +namespace from_stride
> >>>> +{
> >>>> + template<typename Mapping>
> >>>> + constexpr auto
> >>>> + strides(Mapping m)
> >>>> + {
> >>>> + constexpr auto rank = Mapping::extents_type::rank();
> >>>> + std::array<typename Mapping::index_type, rank> s;
> >>>> +
> >>>> + if constexpr (rank > 0)
> >>>> + for(size_t i = 0; i < rank; ++i)
> >>>> + s[i] = m.stride(i);
> >>>> + return s;
> >>>> + }
> >>>> +
> >>>> + template<typename Layout, typename Extents, typename OExtents>
> >>>> + constexpr void
> >>>> + verify_convertible(OExtents oexts)
> >>>> + {
> >>>> + using Mapping = typename Layout::mapping<Extents>;
> >>>> + using OMapping = std::layout_stride::mapping<OExtents>;
> >>>> +
> >>>> + constexpr auto other = OMapping(oexts,
> >>>> strides(Mapping(Extents(oexts))));
> >>>> + if constexpr (std::is_same_v<Layout, std::layout_right>)
> >>>> + ::verify_nothrow_convertible<Mapping>(other);
> >>>> + else
> >>>> + ::verify_convertible<Mapping>(other);
> >>>> + }
> >>>> +
> >>>> + template<typename Layout, typename Extents, typename OExtents>
> >>>> + constexpr void
> >>>> + verify_constructible(OExtents oexts)
> >>>> + {
> >>>> + using Mapping = typename Layout::mapping<Extents>;
> >>>> + using OMapping = std::layout_stride::mapping<OExtents>;
> >>>> +
> >>>> + constexpr auto other = OMapping(oexts,
> >>>> strides(Mapping(Extents(oexts))));
> >>>> + if constexpr (std::is_same_v<Layout, std::layout_right>)
> >>>> + ::verify_nothrow_constructible<Mapping>(other);
> >>>> + else
> >>>> + ::verify_constructible<Mapping>(other);
> >>>> + }
> >>>> +
> >>>> + template<typename Layout>
> >>>> + constexpr bool
> >>>> + test_ctor()
> >>>> + {
> >>>> + assert_not_constructible<
> >>>> + typename Layout::mapping<std::extents<int>>,
> >>>> + std::layout_stride::mapping<std::extents<int, 1>>>();
> >>>> +
> >>>> + assert_not_constructible<
> >>>> + typename Layout::mapping<std::extents<int, 1>>,
> >>>> + std::layout_stride::mapping<std::extents<int>>>();
> >>>> +
> >>>> + assert_not_constructible<
> >>>> + typename Layout::mapping<std::extents<int, 2>>,
> >>>> + std::layout_stride::mapping<std::extents<int, 1>>>();
> >>>> +
> >>>> + verify_convertible<Layout,
> >> std::extents<int>>(std::extents<int>{});
> >>>> +
> >>>> + verify_convertible<Layout, std::extents<unsigned int>>(
> >>>> + std::extents<int>{});
> >>>> +
> >>>> + // Rank == 0 doesn't check IndexType for convertibility.
> >>>> + verify_convertible<Layout, std::extents<int>>(
> >>>> + std::extents<unsigned int>{});
> >>>> +
> >>>> + verify_constructible<Layout, std::extents<int, 3>>(
> >>>> + std::extents<int, 3>{});
> >>>> +
> >>>> + verify_constructible<Layout, std::extents<unsigned int, 3>>(
> >>>> + std::extents<int, 3>{});
> >>>> +
> >>>> + verify_constructible<Layout, std::extents<int, 3>>(
> >>>> + std::extents<unsigned int, 3>{});
> >>>> +
> >>>> + verify_constructible<Layout, std::extents<int, 3, 5>>(
> >>>> + std::extents<int, 3, 5>{});
> >>>> +
> >>>> + verify_constructible<Layout, std::extents<unsigned int, 3, 5>>(
> >>>> + std::extents<int, 3, 5>{});
> >>>> +
> >>>> + verify_constructible<Layout, std::extents<int, 3, 5>>(
> >>>> + std::extents<unsigned int, 3, 5>{});
> >>>> + return true;
> >>>> + }
> >>>> +
> >>>> + template<typename Layout>
> >>>> + constexpr void
> >>>> + test_all()
> >>>> + {
> >>>> + test_ctor<Layout>();
> >>>> + static_assert(test_ctor<Layout>());
> >>>> + }
> >>>> +}
> >>>> +
> >>>> template<typename Layout>
> >>>> constexpr void
> >>>> test_all()
> >>>> @@ -330,6 +428,7 @@ template<typename Layout>
> >>>> default_ctor::test_all<Layout>();
> >>>> from_extents::test_all<Layout>();
> >>>> from_same_layout::test_all<Layout>();
> >>>> + from_stride::test_all<Layout>();
> >>>> }
> >>>>
> >>>> int
> >>>> diff --git
> >> a/libstdc++-v3/testsuite/23_containers/mdspan/layouts/empty.cc
> >>>> b/libstdc++-v3/testsuite/23_containers/mdspan/layouts/empty.cc
> >>>> index dc2a95ebbe6..d550c0a8e84 100644
> >>>> --- a/libstdc++-v3/testsuite/23_containers/mdspan/layouts/empty.cc
> >>>> +++ b/libstdc++-v3/testsuite/23_containers/mdspan/layouts/empty.cc
> >>>> @@ -64,5 +64,6 @@ main()
> >>>> {
> >>>> static_assert(test_all<std::layout_left>());
> >>>> static_assert(test_all<std::layout_right>());
> >>>> + static_assert(test_all<std::layout_stride>());
> >>>> return 0;
> >>>> }
> >>>> diff --git
> >>>> a/libstdc++-v3/testsuite/23_containers/mdspan/layouts/mapping.cc
> >>>> b/libstdc++-v3/testsuite/23_containers/mdspan/layouts/mapping.cc
> >>>> index 4dc0db66865..963c804a369 100644
> >>>> --- a/libstdc++-v3/testsuite/23_containers/mdspan/layouts/mapping.cc
> >>>> +++ b/libstdc++-v3/testsuite/23_containers/mdspan/layouts/mapping.cc
> >>>> @@ -12,6 +12,7 @@ template<typename Layout, typename Extents>
> >>>> {
> >>>> using M = typename Layout::mapping<Extents>;
> >>>> static_assert(std::__mdspan::__is_extents<typename
> >> M::extents_type>);
> >>>> + static_assert(std::__mdspan::__mapping_alike<M>);
> >>>> static_assert(std::copyable<M>);
> >>>> static_assert(std::is_nothrow_move_constructible_v<M>);
> >>>> static_assert(std::is_nothrow_move_assignable_v<M>);
> >>>> @@ -30,6 +31,8 @@ template<typename Layout, typename Extents>
> >>>>
> >>>> static_assert(M::is_always_unique() && M::is_unique());
> >>>> static_assert(M::is_always_strided() && M::is_strided());
> >>>> + if constexpr (!std::is_same_v<Layout, std::layout_stride>)
> >>>> + static_assert(M::is_always_exhaustive() && M::is_exhaustive());
> >>>> return true;
> >>>> }
> >>>>
> >>>> @@ -105,6 +108,39 @@ template<typename Layout>
> >>>> { return exts; }
> >>>> };
> >>>>
> >>>> +template<>
> >>>> + struct MappingFactory<std::layout_stride>
> >>>> + {
> >>>> + template<typename Extents>
> >>>> + static constexpr std::layout_stride::mapping<Extents>
> >>>> + create(Extents exts)
> >>>> + {
> >>>> + if constexpr (Extents::rank() == 0)
> >>>> + {
> >>>> + auto strides = std::array<size_t, 0>{};
> >>>> + return std::layout_stride::mapping(exts, strides);
> >>>> + }
> >>>> + else if constexpr (Extents::rank() == 1)
> >>>> + {
> >>>> + auto strides = std::array<size_t, 1>{2};
> >>>> + return std::layout_stride::mapping(exts, strides);
> >>>> + }
> >>>> + else if constexpr (Extents::rank() == 2)
> >>>> + {
> >>>> + size_t m = exts.extent(1);
> >>>> + auto strides = std::array<size_t, 2>{3*m, 2};
> >>>> + return std::layout_stride::mapping(exts, strides);
> >>>> + }
> >>>> + else if constexpr (Extents::rank() == 3)
> >>>> + {
> >>>> + size_t n = exts.extent(0);
> >>>> + size_t m = exts.extent(1);
> >>>> + auto strides = std::array<size_t, 3>{3*m, 2, 11*m*n};
> >>>> + return std::layout_stride::mapping(exts, strides);
> >>>> + }
> >>>> + }
> >>>> + };
> >>>> +
> >>>> template<typename Layout>
> >>>> constexpr void
> >>>> test_linear_index_3d()
> >>>> @@ -280,6 +316,16 @@ template<typename Layout>
> >>>> VERIFY(m.stride(0) == 1);
> >>>> }
> >>>>
> >>>> +template<>
> >>>> + constexpr void
> >>>> + test_stride_1d<std::layout_stride>()
> >>>> + {
> >>>> + std::array<int, 1> strides{13};
> >>>> + std::layout_stride::mapping m(std::extents<int, 3>{}, strides);
> >>>> + VERIFY(m.stride(0) == strides[0]);
> >>>> + VERIFY(m.strides() == strides);
> >>>> + }
> >>>> +
> >>>> template<typename Layout>
> >>>> constexpr void
> >>>> test_stride_2d();
> >>>> @@ -302,6 +348,17 @@ template<>
> >>>> VERIFY(m.stride(1) == 1);
> >>>> }
> >>>>
> >>>> +template<>
> >>>> + constexpr void
> >>>> + test_stride_2d<std::layout_stride>()
> >>>> + {
> >>>> + std::array<int, 2> strides{13, 2};
> >>>> + std::layout_stride::mapping m(std::extents<int, 3, 5>{},
> strides);
> >>>> + VERIFY(m.stride(0) == strides[0]);
> >>>> + VERIFY(m.stride(1) == strides[1]);
> >>>> + VERIFY(m.strides() == strides);
> >>>> + }
> >>>> +
> >>>> template<typename Layout>
> >>>> constexpr void
> >>>> test_stride_3d();
> >>>> @@ -326,6 +383,19 @@ template<>
> >>>> VERIFY(m.stride(2) == 1);
> >>>> }
> >>>>
> >>>> +template<>
> >>>> + constexpr void
> >>>> + test_stride_3d<std::layout_stride>()
> >>>> + {
> >>>> + std::dextents<int, 3> exts(3, 5, 7);
> >>>> + std::array<int, 3> strides{11, 2, 41};
> >>>> + std::layout_stride::mapping<std::dextents<int, 3>> m(exts,
> >> strides);
> >>>> + VERIFY(m.stride(0) == strides[0]);
> >>>> + VERIFY(m.stride(1) == strides[1]);
> >>>> + VERIFY(m.stride(2) == strides[2]);
> >>>> + VERIFY(m.strides() == strides);
> >>>> + }
> >>>> +
> >>>> template<typename Layout>
> >>>> constexpr bool
> >>>> test_stride_all()
> >>>> @@ -347,7 +417,7 @@ template<typename Layout>
> >>>> test_has_stride_0d()
> >>>> {
> >>>> using Mapping = typename Layout::mapping<std::extents<int>>;
> >>>> - constexpr bool expected = false;
> >>>> + constexpr bool expected = std::is_same_v<Layout,
> >> std::layout_stride>;
> >>>> static_assert(has_stride<Mapping> == expected);
> >>>> }
> >>>>
> >>>> @@ -488,8 +558,11 @@ main()
> >>>> {
> >>>> test_all<std::layout_left>();
> >>>> test_all<std::layout_right>();
> >>>> + test_all<std::layout_stride>();
> >>>>
> >>>> test_has_op_eq<std::layout_right, std::layout_left, false>();
> >>>> + test_has_op_eq<std::layout_right, std::layout_stride, true>();
> >>>> + test_has_op_eq<std::layout_left, std::layout_stride, true>();
> >>>> test_has_op_eq_peculiar();
> >>>> return 0;
> >>>> }
> >>>> diff --git
> >> a/libstdc++-v3/testsuite/23_containers/mdspan/layouts/stride.cc
> >>>> b/libstdc++-v3/testsuite/23_containers/mdspan/layouts/stride.cc
> >>>> new file mode 100644
> >>>> index 00000000000..c8af5c61254
> >>>> --- /dev/null
> >>>> +++ b/libstdc++-v3/testsuite/23_containers/mdspan/layouts/stride.cc
> >>>> @@ -0,0 +1,526 @@
> >>>> +// { dg-do run { target c++23 } }
> >>>> +#include <mdspan>
> >>>> +
> >>>> +#include <testsuite_hooks.h>
> >>>> +
> >>>> +constexpr size_t dyn = std::dynamic_extent;
> >>>> +
> >>>> +template<typename MappingStride>
> >>>> + constexpr void
> >>>> + test_ctor_default_stride()
> >>>> + {
> >>>> + using Extents = typename MappingStride::extents_type;
> >>>> + MappingStride actual;
> >>>> + typename std::layout_right::mapping<Extents> expected;
> >>>> +
> >>>> + constexpr auto rank = MappingStride::extents_type::rank();
> >>>> + if constexpr (rank > 0)
> >>>> + for(size_t i = 0; i < rank; ++i)
> >>>> + VERIFY(actual.stride(i) == expected.stride(i));
> >>>> + }
> >>>> +
> >>>> +constexpr bool
> >>>> +test_ctor_default_stride_all()
> >>>> +{
> >>>> + test_ctor_default_stride<
> >>>> + std::layout_stride::mapping<std::extents<int, 3>>>();
> >>>> +
> >>>> + test_ctor_default_stride<
> >>>> + std::layout_stride::mapping<std::extents<int, 3, 5, 7>>>();
> >>>> +
> >>>> + test_ctor_default_stride<
> >>>> + std::layout_stride::mapping<std::dextents<int, 3>>>();
> >>>> +
> >>>> + test_ctor_default_stride<
> >>>> + std::layout_stride::mapping<std::extents<int, 0, 5, 7>>>();
> >>>> +
> >>>> + test_ctor_default_stride<
> >>>> + std::layout_stride::mapping<std::extents<int, 3, dyn, dyn>>>();
> >>>> +
> >>>> + test_ctor_default_stride<
> >>>> + std::layout_stride::mapping<std::extents<int, dyn, dyn, 3>>>();
> >>>> + return true;
> >>>> +}
> >>>> +
> >>>> +struct IntLikeA
> >>>> +{
> >>>> + operator int()
> >>>> + { return 0; }
> >>>> +};
> >>>> +
> >>>> +struct IntLikeB
> >>>> +{
> >>>> + operator int() noexcept
> >>>> + { return 0; }
> >>>> +};
> >>>> +
> >>>> +struct NotIntLike
> >>>> +{ };
> >>>> +
> >>>> +template<typename E, typename E_arg, typename T, size_t N, bool
> >> Expected>
> >>>> +constexpr void
> >>>> +test_stride_constructible()
> >>>> +{
> >>>> + static_assert(std::is_nothrow_constructible_v<
> >>>> + std::layout_stride::mapping<E>, E_arg, std::span<T, N>> ==
> >>>> Expected);
> >>>> + static_assert(std::is_nothrow_constructible_v<
> >>>> + std::layout_stride::mapping<E>, E_arg, std::array<T, N>> ==
> >>>> Expected);
> >>>> +
> >> static_assert(!std::is_constructible_v<std::layout_stride::mapping<E>,
> >>>> + E_arg>);
> >>>> +}
> >>>> +
> >>>> +constexpr void
> >>>> +test_stride_constructible_all()
> >>>> +{
> >>>> + using E0 = std::extents<int>;
> >>>> + using E1 = std::extents<int, 2>;
> >>>> + using E2 = std::extents<int, dyn>;
> >>>> +
> >>>> + test_stride_constructible<E0, E0, int, 0, true>();
> >>>> + test_stride_constructible<E0, E0, IntLikeA, 0, false>();
> >>>> + test_stride_constructible<E0, E0, IntLikeB, 0, true>();
> >>>> + test_stride_constructible<E0, E0, NotIntLike, 0, false>();
> >>>> + test_stride_constructible<E1, E1, int, 1, true>();
> >>>> + test_stride_constructible<E2, E1, int, 1, true>();
> >>>> + test_stride_constructible<E1, E1, int, 2, false>();
> >>>> + test_stride_constructible<E1, E0, int, 1, false>();
> >>>> +}
> >>>> +
> >>>> +template<typename Extents, typename Shape>
> >>>> + constexpr void
> >>>> + test_ctor_shape_strides(Extents exts, Shape strides)
> >>>> + {
> >>>> + using M = std::layout_stride::mapping<Extents>;
> >>>> + M m(exts, strides);
> >>>> +
> >>>> + if constexpr (Extents::rank() > 0)
> >>>> + for(size_t i = 0; i < exts.rank(); ++i)
> >>>> + {
> >>>> + VERIFY(m.stride(i) == strides[i]);
> >>>> + VERIFY(m.extents().extent(i) == exts.extent(i));
> >>>> + }
> >>>> + }
> >>>> +
> >>>> +constexpr bool
> >>>> +test_ctor_shape_stride_all()
> >>>> +{
> >>>> + test_ctor_shape_strides(std::extents<int>{}, std::array<int, 0>{});
> >>>> + test_ctor_shape_strides(std::extents<int, 2>{}, std::array<int,
> >> 1>{3});
> >>>> + test_ctor_shape_strides(std::extents<int, 2, 4, 6>{},
> >>>> + std::array<int, 3>{20, 5, 45});
> >>>> + return true;
> >>>> +}
> >>>> +
> >>>> +template<typename Extents, std::array<bool, 2> Strided,
> >>>> + std::array<bool, 2> Unique, std::array<bool, 2> Exhautive,
> >>>> + typename Extents::index_type Offset = 0>
> >>>> + struct MappingLike
> >>>> + {
> >>>> + using extents_type = Extents;
> >>>> + using index_type = typename Extents::index_type;
> >>>> +
> >>>> + constexpr
> >>>> + MappingLike(extents_type extents,
> >>>> + std::array<index_type, Extents::rank()> strides)
> >>>> + : _extents(extents), _strides(strides)
> >>>> + { }
> >>>> +
> >>>> + static constexpr bool
> >>>> + is_always_strided() requires (Strided[0])
> >>>> + { return Strided[1]; }
> >>>> +
> >>>> + static constexpr bool
> >>>> + is_always_unique() requires (Unique[0])
> >>>> + { return Unique[1]; }
> >>>> +
> >>>> + static constexpr bool
> >>>> + is_always_exhaustive() requires (Exhautive[0])
> >>>> + { return Exhautive[1]; }
> >>>> +
> >>>> + constexpr Extents
> >>>> + extents() const { return _extents; }
> >>>> +
> >>>> + constexpr index_type
> >>>> + stride(size_t i) const { return _strides[i]; }
> >>>> +
> >>>> + template<typename... Indices>
> >>>> + constexpr index_type
> >>>> + operator()(Indices... indices) const
> >>>> + {
> >>>> + if (empty())
> >>>> + VERIFY(false);
> >>>> +
> >>>> + std::array<index_type, Extents::rank()> ind_arr{indices...};
> >>>> + index_type ret = Offset;
> >>>> + for(size_t i = 0; i < Extents::rank(); ++i)
> >>>> + ret += ind_arr[i]*_strides[i];
> >>>> + return ret;
> >>>> + }
> >>>> +
> >>>> + private:
> >>>> + constexpr bool
> >>>> + empty() const
> >>>> + {
> >>>> + for (size_t i = 0; i < extents_type::rank(); ++i)
> >>>> + if (_extents.extent(i) == 0)
> >>>> + return true;
> >>>> + return false;
> >>>> + }
> >>>> +
> >>>> + Extents _extents;
> >>>> + std::array<index_type, Extents::rank()> _strides;
> >>>> + };
> >>>> +
> >>>> +
> >>>> +template<size_t Rank>
> >>>> +struct ExtentLike
> >>>> +{
> >>>> + using index_type = int;
> >>>> +
> >>>> + static constexpr size_t
> >>>> + rank() { return Rank; }
> >>>> +};
> >>>> +
> >>>> +
> >>>> +template<typename E1>
> >>>> +constexpr void
> >>>> +test_mapping_like_constructible()
> >>>> +{
> >>>> + using M = std::layout_stride::mapping<E1>;
> >>>> + using E2 = std::dextents<typename E1::index_type, E1::rank()>;
> >>>> + using E3 = std::dextents<typename E1::index_type, E1::rank() + 1>;
> >>>> + using E4 = ExtentLike<E1::rank()>;
> >>>> +
> >>>> + constexpr auto TT = std::array{true, true};
> >>>> + constexpr auto FT = std::array{false, true};
> >>>> + constexpr auto TF = std::array{true, false};
> >>>> +
> >>>> + static_assert(std::is_constructible_v<M, MappingLike<E1, TT, TT,
> >> TT>>);
> >>>> + static_assert(std::is_constructible_v<M, MappingLike<E2, TT, TT,
> >> TT>>);
> >>>> + static_assert(!std::is_constructible_v<M, MappingLike<E3, TT, TT,
> >> TT>>);
> >>>> + static_assert(!std::is_constructible_v<M, MappingLike<E1, FT, TT,
> >> TT>>);
> >>>> + static_assert(!std::is_constructible_v<M, MappingLike<E1, TF, TT,
> >> TT>>);
> >>>> + static_assert(!std::is_constructible_v<M, MappingLike<E1, TT, FT,
> >> TT>>);
> >>>> + static_assert(!std::is_constructible_v<M, MappingLike<E1, TT, TF,
> >> TT>>);
> >>>> + static_assert(!std::is_constructible_v<M, MappingLike<E1, TT, TT,
> >> FT>>);
> >>>> + static_assert(std::is_constructible_v<M, MappingLike<E1, TT, TT,
> >> TF>>);
> >>>> + static_assert(!std::is_constructible_v<M, MappingLike<E4, TT, TT,
> >> TF>>);
> >>>> + static_assert(!std::is_constructible_v<M, MappingLike<E4, TT, TT,
> >> TT>>);
> >>>> +}
> >>>> +
> >>>> +constexpr void
> >>>> +test_mapping_like_constructible_all()
> >>>> +{
> >>>> + test_mapping_like_constructible<std::extents<int>>();
> >>>> + test_mapping_like_constructible<std::extents<int, 2>>();
> >>>> + test_mapping_like_constructible<std::extents<int, 2, 3>>();
> >>>> +}
> >>>> +
> >>>> +template<typename E1, typename E2>
> >>>> +constexpr void
> >>>> +test_mapping_like_convertible()
> >>>> +{
> >>>> + using M1 = std::layout_stride::mapping<E1>;
> >>>> + using M2 = std::layout_stride::mapping<E2>;
> >>>> + constexpr auto TT = std::array{true, true};
> >>>> +
> >>>> + static_assert(!std::is_convertible_v<MappingLike<E1, TT, TT, TT>,
> >> M1>);
> >>>> + static_assert(!std::is_convertible_v<MappingLike<E2, TT, TT, TT>,
> >> M1>);
> >>>> + static_assert(!std::is_convertible_v<MappingLike<E1, TT, TT, TT>,
> >> M2>);
> >>>> +
> >>>> +
> static_assert(std::is_convertible_v<std::layout_stride::mapping<E2>,
> >>>> M1>);
> >>>> + static_assert(std::is_convertible_v<std::layout_left::mapping<E2>,
> >> M1>);
> >>>> + static_assert(std::is_convertible_v<std::layout_right::mapping<E2>,
> >>>> M1>);
> >>>> +
> >>>> +
> static_assert(!std::is_convertible_v<std::layout_stride::mapping<E1>,
> >>>> M2>);
> >>>> + static_assert(!std::is_convertible_v<std::layout_left::mapping<E1>,
> >>>> M2>);
> >>>> +
> static_assert(!std::is_convertible_v<std::layout_right::mapping<E1>,
> >>>> M2>);
> >>>> +}
> >>>> +
> >>>> +constexpr void
> >>>> +test_mapping_like_convertible_all()
> >>>> +{
> >>>> + test_mapping_like_convertible<std::extents<unsigned int>,
> >>>> + std::extents<int>>();
> >>>> + test_mapping_like_convertible<std::extents<unsigned int, 2>,
> >>>> + std::extents<int, 2>>();
> >>>> + test_mapping_like_convertible<std::extents<int, dyn, 3>,
> >>>> + std::extents<int, 2, 3>>();
> >>>> +}
> >>>> +
> >>>> +template<typename Extents>
> >>>> +constexpr void
> >>>> +test_ctor_stride_like(Extents exts, std::array<int, Extents::rank()>
> >>>> strides)
> >>>> +{
> >>>> + auto other_right = std::layout_right::mapping(exts);
> >>>> + auto other_left = std::layout_left::mapping(exts);
> >>>> + auto other_stride = std::layout_stride::mapping(exts, strides);
> >>>> +
> >>>> + VERIFY(std::layout_stride::mapping<Extents>(other_right) ==
> >>>> other_right);
> >>>> + VERIFY(std::layout_stride::mapping<Extents>(other_left) ==
> >> other_left);
> >>>> + VERIFY(std::layout_stride::mapping<Extents>(other_stride) ==
> >>>> other_stride);
> >>>> +}
> >>>> +
> >>>> +constexpr void
> >>>> +test_ctor_stride_like_all()
> >>>> +{
> >>>> + using E1 = std::extents<int>;
> >>>> + auto s1 = std::array<int, 0>{};
> >>>> + test_ctor_stride_like(E1{}, s1);
> >>>> +
> >>>> + using E2 = std::extents<int, 3>;
> >>>> + auto s2 = std::array<int, 1>{2};
> >>>> + test_ctor_stride_like(E2{}, s2);
> >>>> +
> >>>> + using E3 = std::extents<int, 3, 5, 7>;
> >>>> + auto s3 = std::array<int, 3>{5, 1, 15};
> >>>> + test_ctor_stride_like(E3{}, s3);
> >>>> +}
> >>>> +
> >>>> +constexpr bool
> >>>> +test_ctor_strides_all()
> >>>> +{
> >>>> + test_ctor_default_stride_all();
> >>>> + test_ctor_shape_stride_all();
> >>>> + test_ctor_stride_like_all();
> >>>> + return true;
> >>>> +}
> >>>> +
> >>>> +// Check is_exhaustive.
> >>>> +template<typename Extents, typename Strides>
> >>>> + constexpr void
> >>>> + test_is_exhaustive(Extents extents, Strides strides, bool expected)
> >>>> + {
> >>>> + std::layout_stride::mapping<Extents> m(extents, strides);
> >>>> + VERIFY(m.is_exhaustive() == expected);
> >>>> +
> >>>> + bool always_exhaustive = extents.rank() == 0 ||
> >>>> m.required_span_size() == 0;
> >>>> + VERIFY(m.is_always_exhaustive() == always_exhaustive);
> >>>> + }
> >>>> +
> >>>> +constexpr void
> >>>> +test_is_exhaustive_zero_1d()
> >>>> +{
> >>>> + std::extents<int, 0> extents;
> >>>> + test_is_exhaustive(extents, std::array{1}, true);
> >>>> + test_is_exhaustive(extents, std::array{2}, true);
> >>>> +}
> >>>> +
> >>>> +constexpr void
> >>>> +test_is_exhaustive_zero_3d()
> >>>> +{
> >>>> + std::extents<int, 3, 0, 7> extents;
> >>>> +
> >>>> + test_is_exhaustive(extents, std::array{1, 1, 1}, true);
> >>>> + test_is_exhaustive(extents, std::array{1, 2*21, 2*3}, true);
> >>>> + test_is_exhaustive(extents, std::array{7, 2*21, 1}, true);
> >>>> + test_is_exhaustive(extents, std::array{1, 21, 3}, true);
> >>>> + test_is_exhaustive(extents, std::array{7, 21, 1}, true);
> >>>> +}
> >>>> +
> >>>> +constexpr void
> >>>> +test_is_exhaustive_0d()
> >>>> +{
> >>>> + std::extents<int> extents;
> >>>> + test_is_exhaustive(extents, std::array<int, 0>{}, true);
> >>>> +}
> >>>> +
> >>>> +constexpr void
> >>>> +test_is_exhaustive_1d()
> >>>> +{
> >>>> + std::extents<int, 3> extents;
> >>>> + test_is_exhaustive(extents, std::array{1}, true);
> >>>> + test_is_exhaustive(extents, std::array{3}, false);
> >>>> +}
> >>>> +
> >>>> +
> >>>> +constexpr void
> >>>> +test_is_exhaustive_3d()
> >>>> +{
> >>>> + std::extents<int, 3, dyn, 7> extents(5);
> >>>> +
> >>>> + test_is_exhaustive(extents, std::array{1, 3, 3*5}, true);
> >>>> + test_is_exhaustive(extents, std::array{5*7, 1, 5}, true);
> >>>> + test_is_exhaustive(extents, std::array{7, 3*7, 1}, true);
> >>>> +
> >>>> + test_is_exhaustive(extents, std::array{1, 3, 2*3*5}, false);
> >>>> + test_is_exhaustive(extents, std::array{2*5*7, 1, 2*5}, false);
> >>>> + test_is_exhaustive(extents, std::array{2*7, 2*3*7, 2}, false);
> >>>> +}
> >>>> +
> >>>> +constexpr void
> >>>> +test_is_exhaustive_ones()
> >>>> +{
> >>>> + std::extents<int, 1, 1, 3, 1> extents;
> >>>> + test_is_exhaustive(extents, std::array{1, 1, 1, 1}, true);
> >>>> + test_is_exhaustive(extents, std::array{1, 1, 1, 3}, true);
> >>>> + test_is_exhaustive(extents, std::array{3, 3, 1, 3}, true);
> >>>> + test_is_exhaustive(extents, std::array{3, 1, 1, 3}, true);
> >>>> +}
> >>>> +
> >>>> +constexpr bool
> >>>> +test_is_exhaustive_all()
> >>>> +{
> >>>> + test_is_exhaustive_zero_1d();
> >>>> + test_is_exhaustive_zero_3d();
> >>>> + test_is_exhaustive_ones();
> >>>> + test_is_exhaustive_0d();
> >>>> + test_is_exhaustive_1d();
> >>>> + test_is_exhaustive_3d();
> >>>> + return true;
> >>>> +}
> >>>> +
> >>>> +template<typename Extents, int Offset>
> >>>> + using OffsetMapping = MappingLike<Extents, {true, true}, {true,
> >> true},
> >>>> + {true, false}, Offset>;
> >>>> +
> >>>> +template<typename Extents>
> >>>> + constexpr void
> >>>> + test_eq(Extents exts,
> >>>> + std::array<typename Extents::index_type, Extents::rank()>
> >>>> left_strides,
> >>>> + std::array<typename Extents::index_type, Extents::rank()>
> >>>> right_strides,
> >>>> + std::array<typename Extents::index_type, Extents::rank()>
> >>>> padded_strides)
> >>>> + {
> >>>> + using DExtents = std::dextents<int, Extents::rank()>;
> >>>> +
> >>>> + std::layout_left::mapping<Extents> ml;
> >>>> + std::layout_right::mapping<DExtents> mr(exts);
> >>>> +
> >>>> + std::layout_stride::mapping<Extents> msd;
> >>>> + std::layout_stride::mapping<Extents> msl(exts, left_strides);
> >>>> + std::layout_stride::mapping<Extents> msr(exts, right_strides);
> >>>> + std::layout_stride::mapping<Extents> msp(exts, padded_strides);
> >>>> +
> >>>> + OffsetMapping<Extents, 0> mor{exts, right_strides};
> >>>> + OffsetMapping<Extents, 0> mol{exts, left_strides};
> >>>> + OffsetMapping<Extents, 0> mop{exts, padded_strides};
> >>>> + OffsetMapping<Extents, 1> moo{exts, right_strides};
> >>>> +
> >>>> + VERIFY(msd == mr);
> >>>> + VERIFY(msd == mor);
> >>>> + VERIFY(msd != msp);
> >>>> + VERIFY(msd != mop);
> >>>> +
> >>>> + VERIFY(msl == ml);
> >>>> + VERIFY(msl == mol);
> >>>> + VERIFY(msd != msp);
> >>>> + VERIFY(msl != mop);
> >>>> +
> >>>> + VERIFY(msp == mop);
> >>>> + VERIFY(msp != ml);
> >>>> + VERIFY(msp != mr);
> >>>> +
> >>>> + VERIFY(msd != moo);
> >>>> + }
> >>>> +
> >>>> +constexpr void
> >>>> +test_eq_0d()
> >>>> +{
> >>>> + using Extents = std::extents<int>;
> >>>> + Extents exts;
> >>>> + std::layout_left::mapping<Extents> ml;
> >>>> + std::layout_right::mapping<Extents> mr;
> >>>> + std::layout_stride::mapping<Extents> ms;
> >>>> + OffsetMapping<Extents, 0> mor{exts, {}};
> >>>> + OffsetMapping<Extents, 1> moo{exts, {}};
> >>>> +
> >>>> + VERIFY(ms == ml);
> >>>> + VERIFY(ms == mr);
> >>>> + VERIFY(ms == mor);
> >>>> + VERIFY(ms != moo);
> >>>> +}
> >>>> +
> >>>> +constexpr void
> >>>> +test_eq_1d()
> >>>> +{
> >>>> + using Extents = std::extents<int, 2>;
> >>>> + auto exhaustive_strides = std::array{1};
> >>>> + auto padded_strides = std::array{2};
> >>>> +
> >>>> + test_eq(Extents{}, exhaustive_strides, exhaustive_strides,
> >>>> padded_strides);
> >>>> +}
> >>>> +
> >>>> +constexpr void
> >>>> +test_eq_2d()
> >>>> +{
> >>>> + using Extents = std::extents<int, 1, 2>;
> >>>> + auto left_strides = std::array{1, 1};
> >>>> + auto right_strides = std::array{2, 1};
> >>>> + auto padded_strides = std::array{2, 8};
> >>>> +
> >>>> + test_eq(Extents{}, left_strides, right_strides, padded_strides);
> >>>> +}
> >>>> +
> >>>> +constexpr void
> >>>> +test_eq_zero()
> >>>> +{
> >>>> + using Extents = std::extents<int, 0, 2>;
> >>>> + using Mapping = std::layout_stride::mapping<Extents>;
> >>>> +
> >>>> + Extents exts;
> >>>> + std::array<int, 2> sl{1, 5};
> >>>> + std::array<int, 2> sr{5, 1};
> >>>> +
> >>>> + Mapping m1(exts, sl);
> >>>> + Mapping m2(exts, sl);
> >>>> + Mapping m3(exts, sr);
> >>>> + OffsetMapping<Extents, 0> m4(exts, sl);
> >>>> +
> >>>> + VERIFY(m1 == m2);
> >>>> + VERIFY(m1 != m3);
> >>>> + VERIFY(m1 == m4);
> >>>> +
> >>>> +}
> >>>> +
> >>>> +constexpr bool
> >>>> +test_eq_all()
> >>>> +{
> >>>> + test_eq_0d();
> >>>> + test_eq_1d();
> >>>> + test_eq_2d();
> >>>> + test_eq_zero();
> >>>> + return true;
> >>>> +}
> >>>> +
> >>>> +template<typename M1, typename M2>
> >>>> + concept has_op_eq = requires (M1 m1, M2 m2)
> >>>> + {
> >>>> + { m1 == m2 } -> std::same_as<bool>;
> >>>> + { m2 == m1 } -> std::same_as<bool>;
> >>>> + { m1 != m2 } -> std::same_as<bool>;
> >>>> + { m2 != m1 } -> std::same_as<bool>;
> >>>> + };
> >>>> +
> >>>> +constexpr void
> >>>> +test_has_op_eq()
> >>>> +{
> >>>> + using E1 = std::extents<int>;
> >>>> + using E2 = std::extents<int, 2>;
> >>>> + using E3 = std::extents<int, 1, 2>;
> >>>> + constexpr auto FT = std::array{false, true};
> >>>> +
> >>>> + static_assert(!has_op_eq<
> >>>> + std::layout_stride::mapping<E1>, MappingLike<E1, FT, FT, FT>>);
> >>>> +
> >>>> + static_assert(!has_op_eq<
> >>>> + std::layout_stride::mapping<E2>, MappingLike<E2, FT, FT, FT>>);
> >>>> +
> >>>> + static_assert(!has_op_eq<
> >>>> + std::layout_stride::mapping<E3>, MappingLike<E3, FT, FT, FT>>);
> >>>> +}
> >>>> +
> >>>> +int
> >>>> +main()
> >>>> +{
> >>>> + test_ctor_strides_all();
> >>>> + static_assert(test_ctor_strides_all());
> >>>> + test_mapping_like_convertible_all();
> >>>> + test_mapping_like_constructible_all();
> >>>> + test_stride_constructible_all();
> >>>> + test_is_exhaustive_all();
> >>>> + static_assert(test_is_exhaustive_all());
> >>>> + test_eq_all();
> >>>> + static_assert(test_eq_all());
> >>>> + test_has_op_eq();
> >>>> + return 0;
> >>>> +}
> >>>> --
> >>>> 2.49.0
> >>>>
> >>>>
> >>>
> >>
> >>
> >
>
>
