Additional concepts, adaptors, and helpers that extend the reference mdspan implementation. More...

Files
file	conjugate_accessor.hpp
	Mdspan accessor adaptor for lazy complex conjugation.

file	diagonal_accessor.hpp
	Accessor support for compressed generalized diagonal tensors.

file	format.hpp
	Formatting support for mdspan extents.

file	generated_accessor.hpp
	Read-only mdspan accessor for values generated from logical indices.

file	generated_layout.hpp
	Synthetic mdspan layout for values generated from logical indices.

file	iteration_plan.hpp
	Helpers for constructing merged iteration plans over strided tensors.

file	mdspan.hpp
	Configured gateway to Uni20's mdspan implementation.

file	mdspec.hpp
	Mdspan-shaped metadata for storage whose data handle requires acquisition.

file	strides.hpp
	Stride utilities for mdspan-like tensors.

file	transform_view.hpp
	Lazy read-only elementwise transform views over mdspan-like inputs.

file	zip_layout.hpp
	Additional layout helpers and policies for zipped mdspan views.

Concepts
concept	uni20::StridedMdspanLike
	An mdspan-like type whose mapping is always strided and exposes stride observers.

concept	uni20::StridedMdspecLike
	An mdspec-like type whose mapping exposes multidimensional strides.

concept	uni20::RankedMdspanLike
	An mdspan-like type with a specified static rank.

concept	uni20::RankedMdspecLike
	An mdspec-like type with a specified static rank.

concept	uni20::MutableRankedMdspanLike
	A mutable mdspan-like type with a specified static rank.

concept	uni20::DefaultAccessorMdspanLike
	An mdspan-like type whose accessor is `stdex::default_accessor`.

concept	uni20::RankedStridedMdspanLike
	A strided mdspan-like type with a specified static rank.

concept	uni20::RankedStridedMdspecLike
	A strided mdspec-like type with a specified static rank.

concept	uni20::MutableRankedStridedMdspanLike
	A mutable strided mdspan-like type with a specified static rank.

concept	uni20::AccessorPolicy
	A model of the C++ mdspan AccessorPolicy named requirement.

concept	uni20::MdspanLike
	A readable type implementing the mdspan observers and multidimensional subscript contract.

concept	uni20::MdspecLike
	Mdspan metadata whose data handle is immediate or available through a data descriptor.

concept	uni20::MutableMdspanLike
	MdspanLike types whose accessor supports indexed assignment.

concept	uni20::MutableMdspecLike
	MdspecLike types whose eventual storage supports writes.

concept	uni20::MutableStridedMdspanLike
	Mutable mdspan-like types whose layout reports they are always strided.

concept	uni20::MutableStridedMdspecLike
	Mutable mdspec-like type whose mapping is always strided.

concept	uni20::DiagonalMdspecLike
	Full logical mdspec with a rank-one view of its generalized diagonal components.

concept	uni20::MutableDiagonalMdspecLike
	Writable generalized-diagonal mdspec with writable rank-one components.

concept	uni20::MutableRankedMdspecLike
	Mutable mdspec-like type with a specified static rank.

concept	uni20::MutableRankedStridedMdspecLike
	Mutable strided mdspec-like type with a specified static rank.

Classes
class	uni20::const_accessor_adaptor< Accessor >
	Adaptor that exposes a mutable lvalue accessor as read-only. More...

struct	uni20::extent_strides< N >
	Structure to represent a common extent and an array of strides. More...

struct	uni20::GeneralZipLayout< Layouts >
	Fallback zip layout for arbitrary mapping policies. More...

struct	uni20::is_default_accessor< Accessor >
	Trait that recognizes the standard mdspan default accessor. More...

struct	uni20::is_default_accessor< stdex::default_accessor< ElementType > >
	Specialization for `stdex::default_accessor<T>`. More...

struct	uni20::span_offset_type< AP, typename >
	Trait to pull an AccessorPolicy’s offset_type if present, or fall back to std::size_t otherwise. More...

struct	uni20::span_offset_type< AP, std::void_t< typename AP::offset_type > >
	Partial specialization that uses an accessor policy’s declared offset_type. More...

struct	uni20::StridedZipLayout< NumSpans >
	Zip layout for `NumSpans` strided spans (all using layout_stride). More...

struct	uni20::StridedZipLayout< NumSpans >::mapping< Ext >
	Nested mapping policy for extents `Ext`, modeling LayoutMappingPolicy. More...

struct	uni20::zip_layout_selector< Spans >
	Picks the right zip layout for a pack of mdspan types. More...

struct	uni20::zip_layout_selector< Spans... >
	Specialization that selects StridedZipLayout when all spans are strided. More...

Typedefs
template<AccessorPolicy Acc>
using	uni20::const_accessor_t = decltype(const_accessor(std::declval< Acc >()))
	Type alias that produces the const-qualified version of an accessor policy.

template<typename AP >
using	uni20::span_offset_t = typename span_offset_type< AP >::type
	Convenience alias for accessor_offset_type<AP>::type.

using	uni20::span_offset_type< AP, typename >::type = std::size_t
	The resulting offset type (std::size_t by default).

using	uni20::span_offset_type< AP, std::void_t< typename AP::offset_type > >::type = typename AP::offset_type
	The resulting offset type defined by the accessor policy.

template<typename... Spans>
using	uni20::zip_layout_t = typename zip_layout_selector< Spans... >::type
	Alias to extract the chosen layout policy for the given spans.

Functions
UNI20_HOST_DEVICE std::array< std::array< index_type, Ext::rank()>, num_spans > const &	uni20::StridedZipLayout< NumSpans >::mapping< Ext >::all_strides () const noexcept
	Retrieve the 2-D array of all per-span strides.

constexpr bool	uni20::extent_strides< N >::can_merge_with_inner (extent_strides inner) const noexcept
	Returns true if the current (outer) dimension and the given inner dimension can be merged.

template<MdspanLike Span, class... Index> requires detail::MdspanIndexPack<Span, Index...>
constexpr decltype(auto)	uni20::const_access (Span const &span, Index... indices)
	Access one mdspan element through a read-only adaptation of its stored accessor.

template<AccessorPolicy Acc> requires (!std::is_const_v<typename Acc::element_type> && std::is_same_v<typename Acc::reference, typename Acc::element_type&>)
constexpr auto	uni20::const_accessor (Acc const &acc)
	Wrap any accessor whose reference is T& into a const adaptor.

template<typename T >
constexpr stdex::default_accessor< T const >	uni20::const_accessor (stdex::default_accessor< T > const &accessor_policy)
	Wrap a default_accessor<T> into a const_default_accessor<T>.

template<typename Ext , typename Str > requires std::is_integral_v<Ext> && std::is_integral_v<Str>
constexpr	uni20::extent_strides< N >::extent_strides (Ext e, std::array< Str, N > s)
	Construct from an extent and an array of strides.

template<typename Ext > requires std::is_integral_v<Ext>
constexpr	uni20::extent_strides< N >::extent_strides (Ext e, std::initializer_list< std::ptrdiff_t > s)
	Construct from an extent and initializer-list strides.

template<typename Ext , typename... Strides> requires (std::is_integral_v<Ext> && sizeof...(Strides) == N)
constexpr	uni20::extent_strides< N >::extent_strides (Ext e, Strides... s)
	Construct from an extent and a parameter pack of stride values.

UNI20_HOST_DEVICE constexpr extents_type const &	uni20::StridedZipLayout< NumSpans >::mapping< Ext >::extents () const noexcept
	Return the extents of the layout.

UNI20_HOST_DEVICE constexpr extents_type const &	uni20::GeneralZipLayout< Layouts >::mapping< Extents >::extents () const noexcept
	Access the common extents.

template<StridedMdspanLike AType, StridedMdspanLike BType, StridedMdspanLike CType, std::size_t N>
auto	uni20::extract_strides (AType const &A, BType const &B, std::array< std::pair< std::size_t, std::size_t >, N > const &contractDims, CType const &C)
	Extract merged stride groups for a tensor contraction.

static UNI20_HOST_DEVICE constexpr bool	uni20::StridedZipLayout< NumSpans >::mapping< Ext >::is_always_exhaustive () noexcept
	Never exhaustive: no single contiguous backing buffer.

static UNI20_HOST_DEVICE constexpr bool	uni20::GeneralZipLayout< Layouts >::mapping< Extents >::is_always_exhaustive () noexcept
	Never exhaustive: no single contiguous backing buffer.

static UNI20_HOST_DEVICE constexpr bool	uni20::StridedZipLayout< NumSpans >::mapping< Ext >::is_always_strided () noexcept
	Statically unknown if strided: may differ per dimension.

static UNI20_HOST_DEVICE constexpr bool	uni20::GeneralZipLayout< Layouts >::mapping< Extents >::is_always_strided () noexcept
	Not strided.

static UNI20_HOST_DEVICE constexpr bool	uni20::StridedZipLayout< NumSpans >::mapping< Ext >::is_always_unique () noexcept
	Always unique for uni20 tensors.

static UNI20_HOST_DEVICE constexpr bool	uni20::GeneralZipLayout< Layouts >::mapping< Extents >::is_always_unique () noexcept
	Always unique for uni20 tensors.

UNI20_HOST_DEVICE constexpr bool	uni20::StridedZipLayout< NumSpans >::mapping< Ext >::is_exhaustive () const noexcept
	Never exhaustive at runtime.

UNI20_HOST_DEVICE constexpr bool	uni20::StridedZipLayout< NumSpans >::mapping< Ext >::is_strided () const noexcept
	True if every dimension uses the same stride across all spans.

UNI20_HOST_DEVICE constexpr bool	uni20::StridedZipLayout< NumSpans >::mapping< Ext >::is_unique () const noexcept
	Always unique at runtime.

UNI20_HOST_DEVICE constexpr	uni20::GeneralZipLayout< Layouts >::mapping< Extents >::mapping (Extents const &ext, typename Layouts::template mapping< Extents > const &... m) noexcept
	Construct child mappings.

template<typename... Mappings>
UNI20_HOST_DEVICE constexpr	uni20::StridedZipLayout< NumSpans >::mapping< Ext >::mapping (extents_type const &exts, Mappings... maps) noexcept
	Construct from extents and existing child mappings.

UNI20_HOST_DEVICE constexpr	uni20::StridedZipLayout< NumSpans >::mapping< Ext >::mapping (extents_type const &exts, std::array< std::array< index_type, Ext::rank()>, NumSpans > const &strides_pack) noexcept
	Construct from shared extents and per-span raw strides.

template<typename LeftMap , typename RightMap > requires (LeftMap::num_spans + RightMap::num_spans == num_spans)
UNI20_HOST_DEVICE constexpr	uni20::StridedZipLayout< NumSpans >::mapping< Ext >::mapping (LeftMap const &left, RightMap const &right) noexcept
	Merge two sub-mappings whose span counts sum to NumSpans.

template<typename OtherExt >
UNI20_HOST_DEVICE constexpr	uni20::StridedZipLayout< NumSpans >::mapping< Ext >::mapping (std::array< index_type, Ext::rank()> const &new_strides, typename StridedZipLayout< num_spans - 1 >::template mapping< OtherExt > const &other) noexcept
	Prepend one span’s strides before an existing mapping of N–1 spans.

template<typename OtherExt >
UNI20_HOST_DEVICE constexpr	uni20::StridedZipLayout< NumSpans >::mapping< Ext >::mapping (typename StridedZipLayout< num_spans - 1 >::template mapping< OtherExt > const &other, std::array< index_type, Ext::rank()> const &new_strides) noexcept
	Append one span’s strides after an existing mapping of N–1 spans.

template<typename Extents , std::size_t R> requires (Extents::rank() == R)
static_vector< extent_strides< 2 >, R >	uni20::merge_strides_left (Extents const &ext, std::array< std::ptrdiff_t, R > const &Stride1, std::array< std::ptrdiff_t, R > const &Stride2)
	Build and merge stride metadata from two stride arrays favouring column-major (left) order.

template<std::size_t N, std::size_t R>
void	uni20::merge_strides_left (static_vector< extent_strides< N >, R > &out)
	Merge adjacent stride descriptors in place using column-major (left) ordering.

template<typename Extents , std::size_t R> requires (Extents::rank() == R)
static_vector< extent_strides< 2 >, R >	uni20::merge_strides_right (Extents const &ext, std::array< std::ptrdiff_t, R > const &Stride1, std::array< std::ptrdiff_t, R > const &Stride2)
	Build and merge stride metadata from two stride arrays favouring row-major (right) order.

template<std::size_t N, std::size_t R>
void	uni20::merge_strides_right (static_vector< extent_strides< N >, R > &out)
	Merge adjacent stride descriptors in place using row-major (right) ordering.

constexpr void	uni20::extent_strides< N >::merge_with_inner (extent_strides inner) noexcept
	Merge an inner dimension into this one when merging is valid.

UNI20_HOST_DEVICE constexpr bool	uni20::GeneralZipLayout< Layouts >::mapping< Extents >::operator!= (mapping const &o) const noexcept
	Compare two mappings for inequality.

template<typename... Idx>
UNI20_HOST_DEVICE constexpr offset_type	uni20::StridedZipLayout< NumSpans >::mapping< Ext >::operator() (Idx... idxs) const noexcept
	Compute per-span linear offsets for a multi-index.

template<typename... Idx>
UNI20_HOST_DEVICE constexpr offset_type	uni20::GeneralZipLayout< Layouts >::mapping< Extents >::operator() (Idx... idxs) const noexcept
	Compute the per-layout offsets for a given multi-index.

UNI20_HOST_DEVICE constexpr bool	uni20::GeneralZipLayout< Layouts >::mapping< Extents >::operator== (mapping const &o) const noexcept
	Compare two mappings for equality.

UNI20_HOST_DEVICE constexpr std::size_t	uni20::GeneralZipLayout< Layouts >::mapping< Extents >::required_span_size () const noexcept
	Return the maximum required span size among the child mappings.

UNI20_HOST_DEVICE constexpr index_type	uni20::StridedZipLayout< NumSpans >::mapping< Ext >::stride (rank_type r) const noexcept
	Return the common stride in dimension `r`.

UNI20_HOST_DEVICE constexpr std::array< index_type, Ext::rank()>	uni20::StridedZipLayout< NumSpans >::mapping< Ext >::strides () const noexcept
	Return the common strides for each dimension.

template<StridedMdspecLike S>
auto	uni20::strides (S const &s)
	Retrieve the strides associated with a strided mdspec-like type.

Variables
template<class Accessor >
constexpr bool	uni20::is_default_accessor_v = is_default_accessor<std::remove_cvref_t<Accessor>>::value
	True when an accessor is `stdex::default_accessor<T>`.

static constexpr std::size_t	uni20::StridedZipLayout< NumSpans >::mapping< Ext >::num_spans = NumSpans
	Number of spans in this zip layout.

Detailed Description

Additional concepts, adaptors, and helpers that extend the reference mdspan implementation.

Typedef Documentation

◆ const_accessor_t

template<AccessorPolicy Acc>

using uni20::const_accessor_t = typedef decltype(const_accessor(std::declval<Acc>()))

Type alias that produces the const-qualified version of an accessor policy.

Template Parameters

Acc	An accessor policy.

◆ span_offset_t

template<typename AP >

using uni20::span_offset_t = typedef typename span_offset_type<AP>::type

Convenience alias for accessor_offset_type<AP>::type.

Template Parameters

AP	The accessor policy to inspect.

◆ type [1/2]

template<typename AP , typename = void>

using uni20::span_offset_type< AP, typename >::type = std::size_t

The resulting offset type (std::size_t by default).

◆ type [2/2]

template<typename AP >

using uni20::span_offset_type< AP, std::void_t< typename AP::offset_type > >::type = typename AP::offset_type

The resulting offset type defined by the accessor policy.

◆ zip_layout_t

template<typename... Spans>

using uni20::zip_layout_t = typedef typename zip_layout_selector<Spans...>::type

Alias to extract the chosen layout policy for the given spans.

Template Parameters

Spans Mdspan types.

Function Documentation

◆ all_strides()

template<std::size_t NumSpans>

template<typename Ext >

UNI20_HOST_DEVICE std::array< std::array< index_type, Ext::rank()>, num_spans > const & uni20::StridedZipLayout< NumSpans >::mapping< Ext >::all_strides ( ) const

inlinenoexcept

Retrieve the 2-D array of all per-span strides.

Returns: An array [span][dim] of strides.

◆ can_merge_with_inner()

template<std::size_t N>

constexpr bool uni20::extent_strides< N >::can_merge_with_inner ( extent_strides< N > inner ) const

inlineconstexprnoexcept

Returns true if the current (outer) dimension and the given inner dimension can be merged.

An extent-one dimension is always mergeable because its stride is not observed by any logical index.

Parameters

inner The inner dimension metadata to test.

Returns: True when the two dimensions are mergeable.

◆ const_access()

template<MdspanLike Span, class... Index>
requires detail::MdspanIndexPack<Span, Index...>

constexpr decltype(auto) uni20::const_access	(	Span const &	span,
		Index...	indices
	)

constexpr

Access one mdspan element through a read-only adaptation of its stored accessor.

This preserves the mapping and accessor state without constructing a second mdspan descriptor. Index eligibility and conversion match the multidimensional mdspan subscript operation.

Template Parameters

Span	The mdspan-like descriptor type.
Index	One index type per mdspan rank.

Parameters

span	Descriptor whose mapping, handle, and accessor are used.
indices	Coordinates for every mdspan axis.

Returns: The reference or calculated value produced by the read-only accessor.

◆ const_accessor() [1/2]

template<AccessorPolicy Acc>
requires (!std::is_const_v<typename Acc::element_type> && std::is_same_v<typename Acc::reference, typename Acc::element_type&>)

constexpr auto uni20::const_accessor ( Acc const & acc )

constexpr

Wrap any accessor whose reference is T& into a const adaptor.

Template Parameters

Acc	A mutable accessor policy with reference equal to `element_type&`.

Parameters

acc	The accessor to wrap.

Returns: A const-qualified accessor adaptor.

◆ const_accessor() [2/2]

template<typename T >

constexpr stdex::default_accessor< T const > uni20::const_accessor ( stdex::default_accessor< T > const & accessor_policy )

constexpr

Wrap a default_accessor<T> into a const_default_accessor<T>.

Template Parameters

T	Element type accessed by the policy.

Parameters

accessor_policy The accessor policy to upgrade.

Returns: A default accessor for T const.

◆ extent_strides() [1/3]

template<std::size_t N>

template<typename Ext , typename Str >
requires std::is_integral_v<Ext> && std::is_integral_v<Str>

constexpr uni20::extent_strides< N >::extent_strides	(	Ext	e,
		std::array< Str, N >	s
	)

inlineconstexpr

Construct from an extent and an array of strides.

Template Parameters

Ext	Integral type for the extent.
Str	Integral type for the stride values.

Parameters

e	The extent value.
s	The strides associated with the dimension.

◆ extent_strides() [2/3]

template<std::size_t N>

template<typename Ext >
requires std::is_integral_v<Ext>

constexpr uni20::extent_strides< N >::extent_strides	(	Ext	e,
		std::initializer_list< std::ptrdiff_t >	s
	)

inlineconstexpr

Construct from an extent and initializer-list strides.

Template Parameters

Ext	Integral type for the extent.

Parameters

e	The extent value.
s	The strides associated with the dimension.

◆ extent_strides() [3/3]

template<std::size_t N>

template<typename Ext , typename... Strides>
requires (std::is_integral_v<Ext> && sizeof...(Strides) == N)

constexpr uni20::extent_strides< N >::extent_strides	(	Ext	e,
		Strides...	s
	)

inlineconstexpr

Construct from an extent and a parameter pack of stride values.

Template Parameters

Ext	Integral type for the extent.
Strides	Integral stride arguments matching `N`.

Parameters

e	The extent value.
s	The stride values.

◆ extents() [1/2]

template<std::size_t NumSpans>

template<typename Ext >

UNI20_HOST_DEVICE constexpr extents_type const & uni20::StridedZipLayout< NumSpans >::mapping< Ext >::extents ( ) const

inlineconstexprnoexcept

Return the extents of the layout.

Returns: The common extents of all child layouts.

◆ extents() [2/2]

template<typename... Layouts>

template<typename Extents >

UNI20_HOST_DEVICE constexpr extents_type const & uni20::GeneralZipLayout< Layouts >::mapping< Extents >::extents ( ) const

inlineconstexprnoexcept

Access the common extents.

Returns: Shared extents across all child mappings.

◆ extract_strides()

template<StridedMdspanLike AType, StridedMdspanLike BType, StridedMdspanLike CType, std::size_t N>

auto uni20::extract_strides	(	AType const &	A,
		BType const &	B,
		std::array< std::pair< std::size_t, std::size_t >, N > const &	contractDims,
		CType const &	C
	)

Extract merged stride groups for a tensor contraction.

Template Parameters

AType	Strided mdspan describing the A operand.
BType	Strided mdspan describing the B operand.
CType	Strided mdspan describing the C operand.
N	Number of contraction dimensions.

Parameters

A	The left operand tensor.
B	The right operand tensor.
contractDims	Pairs of contraction indices mapping A to B dimensions.
C	The output tensor.

Returns: Tuple of stride descriptors for the M, N, and K groupings.

◆ is_always_exhaustive() [1/2]

template<std::size_t NumSpans>

template<typename Ext >

static UNI20_HOST_DEVICE constexpr bool uni20::StridedZipLayout< NumSpans >::mapping< Ext >::is_always_exhaustive ( )

inlinestaticconstexprnoexcept

Never exhaustive: no single contiguous backing buffer.

◆ is_always_exhaustive() [2/2]

template<typename... Layouts>

template<typename Extents >

static UNI20_HOST_DEVICE constexpr bool uni20::GeneralZipLayout< Layouts >::mapping< Extents >::is_always_exhaustive ( )

inlinestaticconstexprnoexcept

Never exhaustive: no single contiguous backing buffer.

◆ is_always_strided() [1/2]

template<std::size_t NumSpans>

template<typename Ext >

static UNI20_HOST_DEVICE constexpr bool uni20::StridedZipLayout< NumSpans >::mapping< Ext >::is_always_strided ( )

inlinestaticconstexprnoexcept

Statically unknown if strided: may differ per dimension.

◆ is_always_strided() [2/2]

template<typename... Layouts>

template<typename Extents >

static UNI20_HOST_DEVICE constexpr bool uni20::GeneralZipLayout< Layouts >::mapping< Extents >::is_always_strided ( )

inlinestaticconstexprnoexcept

Not strided.

◆ is_always_unique() [1/2]

template<std::size_t NumSpans>

template<typename Ext >

static UNI20_HOST_DEVICE constexpr bool uni20::StridedZipLayout< NumSpans >::mapping< Ext >::is_always_unique ( )

inlinestaticconstexprnoexcept

Always unique for uni20 tensors.

◆ is_always_unique() [2/2]

template<typename... Layouts>

template<typename Extents >

static UNI20_HOST_DEVICE constexpr bool uni20::GeneralZipLayout< Layouts >::mapping< Extents >::is_always_unique ( )

inlinestaticconstexprnoexcept

Always unique for uni20 tensors.

◆ is_exhaustive()

template<std::size_t NumSpans>

template<typename Ext >

UNI20_HOST_DEVICE constexpr bool uni20::StridedZipLayout< NumSpans >::mapping< Ext >::is_exhaustive ( ) const

inlineconstexprnoexcept

Never exhaustive at runtime.

◆ is_strided()

template<std::size_t NumSpans>

template<typename Ext >

UNI20_HOST_DEVICE constexpr bool uni20::StridedZipLayout< NumSpans >::mapping< Ext >::is_strided ( ) const

inlineconstexprnoexcept

True if every dimension uses the same stride across all spans.

Returns: True when each span shares identical strides per dimension.

◆ is_unique()

template<std::size_t NumSpans>

template<typename Ext >

UNI20_HOST_DEVICE constexpr bool uni20::StridedZipLayout< NumSpans >::mapping< Ext >::is_unique ( ) const

inlineconstexprnoexcept

Always unique at runtime.

◆ mapping() [1/6]

template<typename... Layouts>

template<typename Extents >

UNI20_HOST_DEVICE constexpr uni20::GeneralZipLayout< Layouts >::mapping< Extents >::mapping	(	Extents const &	ext,
		typename Layouts::template mapping< Extents > const &...	m
	)

inlineexplicitconstexprnoexcept

Construct child mappings.

Parameters

ext	Common extents shared by every mapping.
m	Child mappings stored within the layout.

◆ mapping() [2/6]

template<std::size_t NumSpans>

template<typename Ext >

template<typename... Mappings>

UNI20_HOST_DEVICE constexpr uni20::StridedZipLayout< NumSpans >::mapping< Ext >::mapping	(	extents_type const &	exts,
		Mappings...	maps
	)

inlineconstexprnoexcept

Construct from extents and existing child mappings.

Parameters

exts	Shared extents of all spans.
maps	Existing mappings whose strides are copied into this layout.

◆ mapping() [3/6]

template<std::size_t NumSpans>

template<typename Ext >

UNI20_HOST_DEVICE constexpr uni20::StridedZipLayout< NumSpans >::mapping< Ext >::mapping	(	extents_type const &	exts,
		std::array< std::array< index_type, Ext::rank()>, NumSpans > const &	strides_pack
	)

inlineconstexprnoexcept

Construct from shared extents and per-span raw strides.

Parameters

exts	Common extents of the view.
strides_pack	strides_pack[s][d] is the stride of span s in dimension d.

◆ mapping() [4/6]

template<std::size_t NumSpans>

template<typename Ext >

template<typename LeftMap , typename RightMap >
requires (LeftMap::num_spans + RightMap::num_spans == num_spans)

UNI20_HOST_DEVICE constexpr uni20::StridedZipLayout< NumSpans >::mapping< Ext >::mapping	(	LeftMap const &	left,
		RightMap const &	right
	)

inlineconstexprnoexcept

Merge two sub-mappings whose span counts sum to NumSpans.

Template Parameters

LeftMap	Mapping of the first n spans.
RightMap	Mapping of the remaining spans.

◆ mapping() [5/6]

template<std::size_t NumSpans>

template<typename Ext >

template<typename OtherExt >

UNI20_HOST_DEVICE constexpr uni20::StridedZipLayout< NumSpans >::mapping< Ext >::mapping	(	std::array< index_type, Ext::rank()> const &	new_strides,
		typename StridedZipLayout< num_spans - 1 >::template mapping< OtherExt > const &	other
	)

inlineconstexprnoexcept

Prepend one span’s strides before an existing mapping of N–1 spans.

Template Parameters

OtherExt Extents type of the smaller mapping.

◆ mapping() [6/6]

template<std::size_t NumSpans>

template<typename Ext >

template<typename OtherExt >

UNI20_HOST_DEVICE constexpr uni20::StridedZipLayout< NumSpans >::mapping< Ext >::mapping	(	typename StridedZipLayout< num_spans - 1 >::template mapping< OtherExt > const &	other,
		std::array< index_type, Ext::rank()> const &	new_strides
	)

inlineconstexprnoexcept

Append one span’s strides after an existing mapping of N–1 spans.

Template Parameters

OtherExt Extents type of the smaller mapping.

◆ merge_strides_left() [1/2]

template<typename Extents , std::size_t R>
requires (Extents::rank() == R)

static_vector< extent_strides< 2 >, R > uni20::merge_strides_left	(	Extents const &	ext,
		std::array< std::ptrdiff_t, R > const &	Stride1,
		std::array< std::ptrdiff_t, R > const &	Stride2
	)

inline

Build and merge stride metadata from two stride arrays favouring column-major (left) order.

Template Parameters

Extents	Extents type supplying extents via `operator`[].
R	Tensor rank captured by the stride arrays.

Parameters

ext	The extents of the tensor.
Stride1	The strides for the first operand.
Stride2	The strides for the second operand.

Returns: A compacted sequence of stride descriptors sorted by increasing primary stride.

◆ merge_strides_left() [2/2]

template<std::size_t N, std::size_t R>

void uni20::merge_strides_left ( static_vector< extent_strides< N >, R > & out )

Merge adjacent stride descriptors in place using column-major (left) ordering.

Template Parameters

N	Number of stride values per descriptor.
R	Capacity of the static vector.

Parameters

out	The sequence of stride descriptors to compact.

◆ merge_strides_right() [1/2]

template<typename Extents , std::size_t R>
requires (Extents::rank() == R)

static_vector< extent_strides< 2 >, R > uni20::merge_strides_right	(	Extents const &	ext,
		std::array< std::ptrdiff_t, R > const &	Stride1,
		std::array< std::ptrdiff_t, R > const &	Stride2
	)

inline

Build and merge stride metadata from two stride arrays favouring row-major (right) order.

Template Parameters

Extents	Extents type supplying extents via `operator`[].
R	Tensor rank captured by the stride arrays.

Parameters

ext	The extents of the tensor.
Stride1	The strides for the first operand.
Stride2	The strides for the second operand.

Returns: A compacted sequence of stride descriptors sorted by decreasing primary stride.

◆ merge_strides_right() [2/2]

template<std::size_t N, std::size_t R>

void uni20::merge_strides_right ( static_vector< extent_strides< N >, R > & out )

Merge adjacent stride descriptors in place using row-major (right) ordering.

Template Parameters

N	Number of stride values per descriptor.
R	Capacity of the static vector.

Parameters

out	The sequence of stride descriptors to compact.

◆ merge_with_inner()

template<std::size_t N>

constexpr void uni20::extent_strides< N >::merge_with_inner ( extent_strides< N > inner )

inlineconstexprnoexcept

Merge an inner dimension into this one when merging is valid.

The merged descriptor retains the non-singleton dimension's strides. Two singleton dimensions use canonical unit strides.

Parameters

inner The inner dimension metadata to merge.

◆ operator!=()

template<typename... Layouts>

template<typename Extents >

UNI20_HOST_DEVICE constexpr bool uni20::GeneralZipLayout< Layouts >::mapping< Extents >::operator!= ( mapping< Extents > const & o ) const

inlineconstexprnoexcept

Compare two mappings for inequality.

Parameters

o	Mapping to compare against.

Returns: True when either extents or child mappings differ.

◆ operator()() [1/2]

template<std::size_t NumSpans>

template<typename Ext >

template<typename... Idx>

UNI20_HOST_DEVICE constexpr offset_type uni20::StridedZipLayout< NumSpans >::mapping< Ext >::operator() ( Idx... idxs ) const

inlineconstexprnoexcept

Compute per-span linear offsets for a multi-index.

Template Parameters

Idx	Types of each index argument.

Parameters

idxs	Indices for each dimension.

Returns: Array of per-span offsets.

◆ operator()() [2/2]

template<typename... Layouts>

template<typename Extents >

template<typename... Idx>

UNI20_HOST_DEVICE constexpr offset_type uni20::GeneralZipLayout< Layouts >::mapping< Extents >::operator() ( Idx... idxs ) const

inlineconstexprnoexcept

Compute the per-layout offsets for a given multi-index.

Template Parameters

Idx	Types of each index argument.

Parameters

idxs	Indices for each dimension.

Returns: Tuple containing offsets for every child mapping.

◆ operator==()

template<typename... Layouts>

template<typename Extents >

UNI20_HOST_DEVICE constexpr bool uni20::GeneralZipLayout< Layouts >::mapping< Extents >::operator== ( mapping< Extents > const & o ) const

inlineconstexprnoexcept

Compare two mappings for equality.

Parameters

o	Mapping to compare against.

Returns: True when both extents and child mappings match.

◆ required_span_size()

template<typename... Layouts>

template<typename Extents >

UNI20_HOST_DEVICE constexpr std::size_t uni20::GeneralZipLayout< Layouts >::mapping< Extents >::required_span_size ( ) const

inlineconstexprnoexcept

Return the maximum required span size among the child mappings.

Returns: Maximum number of elements any child mapping may touch.

◆ stride()

template<std::size_t NumSpans>

template<typename Ext >

UNI20_HOST_DEVICE constexpr index_type uni20::StridedZipLayout< NumSpans >::mapping< Ext >::stride ( rank_type r ) const

inlineconstexprnoexcept

Return the common stride in dimension r.

Precondition: All spans share the same stride in dimension r.

Parameters

r	Dimension index, 0 ≤ r < rank().

Returns: The stride (step) in the flattened data for dim r.

◆ strides() [1/2]

template<std::size_t NumSpans>

template<typename Ext >

UNI20_HOST_DEVICE constexpr std::array< index_type, Ext::rank()> uni20::StridedZipLayout< NumSpans >::mapping< Ext >::strides ( ) const

inlineconstexprnoexcept

Return the common strides for each dimension.

Returns: Array of strides indexed by dimension.

◆ strides() [2/2]

template<StridedMdspecLike S>

auto uni20::strides ( S const & s )

Retrieve the strides associated with a strided mdspec-like type.

Template Parameters

S	The strided mdspec-like type.

Parameters

s	The multidimensional descriptor whose strides will be returned.

Returns: A std::array containing the strides for each rank.

Variable Documentation

◆ is_default_accessor_v

template<class Accessor >

constexpr bool uni20::is_default_accessor_v = is_default_accessor<std::remove_cvref_t<Accessor>>::value

inlineconstexpr

True when an accessor is stdex::default_accessor<T>.

Template Parameters

Accessor Candidate accessor policy.

◆ num_spans

template<std::size_t NumSpans>

template<typename Ext >

constexpr std::size_t uni20::StridedZipLayout< NumSpans >::mapping< Ext >::num_spans = NumSpans

staticconstexpr

Number of spans in this zip layout.

Files

Concepts

Classes

Typedefs

Functions

Variables

Detailed Description

Typedef Documentation

◆ const_accessor_t

◆ span_offset_t

◆ type [1/2]

◆ type [2/2]

◆ zip_layout_t

Function Documentation

◆ all_strides()

◆ can_merge_with_inner()

◆ const_access()

◆ const_accessor() [1/2]

◆ const_accessor() [2/2]

◆ extent_strides() [1/3]

◆ extent_strides() [2/3]

◆ extent_strides() [3/3]

◆ extents() [1/2]

◆ extents() [2/2]

◆ extract_strides()

◆ is_always_exhaustive() [1/2]

◆ is_always_exhaustive() [2/2]

◆ is_always_strided() [1/2]

◆ is_always_strided() [2/2]

◆ is_always_unique() [1/2]

◆ is_always_unique() [2/2]

◆ is_exhaustive()

◆ is_strided()

◆ is_unique()

◆ mapping() [1/6]

◆ mapping() [2/6]

◆ mapping() [3/6]

◆ mapping() [4/6]

◆ mapping() [5/6]

◆ mapping() [6/6]

◆ merge_strides_left() [1/2]

◆ merge_strides_left() [2/2]

◆ merge_strides_right() [1/2]

◆ merge_strides_right() [2/2]

◆ merge_with_inner()

◆ operator!=()

◆ operator()() [1/2]

◆ operator()() [2/2]

◆ operator==()

◆ required_span_size()

◆ stride()

◆ strides() [1/2]

◆ strides() [2/2]

Variable Documentation

◆ is_default_accessor_v

◆ num_spans