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pocketpy/3rd/numpy/include/xtensor/xstrided_view_base.hpp
Anurag Bhat 86b4fc623c
Merge numpy to pocketpy (#303) 
* Merge numpy to pocketpy

* Add CI

* Fix CI
2024-09-02 16:22:41 +08:00

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/***************************************************************************
* Copyright (c) Johan Mabille, Sylvain Corlay and Wolf Vollprecht *
* Copyright (c) QuantStack *
* *
* Distributed under the terms of the BSD 3-Clause License. *
* *
* The full license is in the file LICENSE, distributed with this software. *
****************************************************************************/
#ifndef XTENSOR_STRIDED_VIEW_BASE_HPP
#define XTENSOR_STRIDED_VIEW_BASE_HPP
#include <type_traits>
#include <xtl/xsequence.hpp>
#include <xtl/xvariant.hpp>
#include "xaccessible.hpp"
#include "xslice.hpp"
#include "xstrides.hpp"
#include "xtensor_config.hpp"
#include "xtensor_forward.hpp"
#include "xutils.hpp"
namespace xt
{
namespace detail
{
template <class CT, layout_type L>
class flat_expression_adaptor
{
public:
using xexpression_type = std::decay_t<CT>;
using shape_type = typename xexpression_type::shape_type;
using inner_strides_type = get_strides_t<shape_type>;
using index_type = inner_strides_type;
using size_type = typename xexpression_type::size_type;
using value_type = typename xexpression_type::value_type;
using const_reference = typename xexpression_type::const_reference;
using reference = std::conditional_t<
std::is_const<std::remove_reference_t<CT>>::value,
typename xexpression_type::const_reference,
typename xexpression_type::reference>;
using iterator = decltype(std::declval<std::remove_reference_t<CT>>().template begin<L>());
using const_iterator = decltype(std::declval<std::decay_t<CT>>().template cbegin<L>());
using reverse_iterator = decltype(std::declval<std::remove_reference_t<CT>>().template rbegin<L>());
using const_reverse_iterator = decltype(std::declval<std::decay_t<CT>>().template crbegin<L>());
explicit flat_expression_adaptor(CT* e);
template <class FST>
flat_expression_adaptor(CT* e, FST&& strides);
void update_pointer(CT* ptr) const;
size_type size() const;
reference operator[](size_type idx);
const_reference operator[](size_type idx) const;
iterator begin();
iterator end();
const_iterator begin() const;
const_iterator end() const;
const_iterator cbegin() const;
const_iterator cend() const;
private:
static index_type& get_index();
mutable CT* m_e;
inner_strides_type m_strides;
size_type m_size;
};
template <class T>
struct is_flat_expression_adaptor : std::false_type
{
};
template <class CT, layout_type L>
struct is_flat_expression_adaptor<flat_expression_adaptor<CT, L>> : std::true_type
{
};
template <class E, class ST>
struct provides_data_interface
: xtl::conjunction<has_data_interface<std::decay_t<E>>, xtl::negation<is_flat_expression_adaptor<ST>>>
{
};
}
template <class D>
class xstrided_view_base : public xaccessible<D>
{
public:
using base_type = xaccessible<D>;
using inner_types = xcontainer_inner_types<D>;
using xexpression_type = typename inner_types::xexpression_type;
using undecay_expression = typename inner_types::undecay_expression;
static constexpr bool is_const = std::is_const<std::remove_reference_t<undecay_expression>>::value;
using value_type = typename xexpression_type::value_type;
using reference = typename inner_types::reference;
using const_reference = typename inner_types::const_reference;
using pointer = std::
conditional_t<is_const, typename xexpression_type::const_pointer, typename xexpression_type::pointer>;
using const_pointer = typename xexpression_type::const_pointer;
using size_type = typename inner_types::size_type;
using difference_type = typename xexpression_type::difference_type;
using storage_getter = typename inner_types::storage_getter;
using inner_storage_type = typename inner_types::inner_storage_type;
using storage_type = std::remove_reference_t<inner_storage_type>;
using shape_type = typename inner_types::shape_type;
using strides_type = get_strides_t<shape_type>;
using backstrides_type = strides_type;
using inner_shape_type = shape_type;
using inner_strides_type = strides_type;
using inner_backstrides_type = backstrides_type;
using undecay_shape = typename inner_types::undecay_shape;
using simd_value_type = xt_simd::simd_type<value_type>;
using bool_load_type = typename xexpression_type::bool_load_type;
static constexpr layout_type static_layout = inner_types::layout;
static constexpr bool contiguous_layout = static_layout != layout_type::dynamic
&& xexpression_type::contiguous_layout;
template <class CTA, class SA>
xstrided_view_base(CTA&& e, SA&& shape, strides_type&& strides, size_type offset, layout_type layout) noexcept;
xstrided_view_base(xstrided_view_base&& rhs);
xstrided_view_base(const xstrided_view_base& rhs);
const inner_shape_type& shape() const noexcept;
const inner_strides_type& strides() const noexcept;
const inner_backstrides_type& backstrides() const noexcept;
layout_type layout() const noexcept;
bool is_contiguous() const noexcept;
using base_type::shape;
reference operator()();
const_reference operator()() const;
template <class... Args>
reference operator()(Args... args);
template <class... Args>
const_reference operator()(Args... args) const;
template <class... Args>
reference unchecked(Args... args);
template <class... Args>
const_reference unchecked(Args... args) const;
template <class It>
reference element(It first, It last);
template <class It>
const_reference element(It first, It last) const;
storage_type& storage() noexcept;
const storage_type& storage() const noexcept;
template <class E = xexpression_type, class ST = storage_type>
std::enable_if_t<detail::provides_data_interface<E, ST>::value, pointer> data() noexcept;
template <class E = xexpression_type, class ST = storage_type>
std::enable_if_t<detail::provides_data_interface<E, ST>::value, const_pointer> data() const noexcept;
size_type data_offset() const noexcept;
xexpression_type& expression() noexcept;
const xexpression_type& expression() const noexcept;
template <class O>
bool broadcast_shape(O& shape, bool reuse_cache = false) const;
template <class O>
bool has_linear_assign(const O& strides) const noexcept;
protected:
using offset_type = typename strides_type::value_type;
template <class... Args>
offset_type compute_index(Args... args) const;
template <class... Args>
offset_type compute_unchecked_index(Args... args) const;
template <class It>
offset_type compute_element_index(It first, It last) const;
void set_offset(size_type offset);
private:
undecay_expression m_e;
inner_storage_type m_storage;
inner_shape_type m_shape;
inner_strides_type m_strides;
inner_backstrides_type m_backstrides;
size_type m_offset;
layout_type m_layout;
};
/***************************
* flat_expression_adaptor *
***************************/
namespace detail
{
template <class CT>
struct inner_storage_getter
{
using type = decltype(std::declval<CT>().storage());
using reference = std::add_lvalue_reference_t<CT>;
template <class E>
using rebind_t = inner_storage_getter<E>;
static decltype(auto) get_flat_storage(reference e)
{
return e.storage();
}
static auto get_offset(reference e)
{
return e.data_offset();
}
static decltype(auto) get_strides(reference e)
{
return e.strides();
}
};
template <class CT, layout_type L>
struct flat_adaptor_getter
{
using type = flat_expression_adaptor<std::remove_reference_t<CT>, L>;
using reference = std::add_lvalue_reference_t<CT>;
template <class E>
using rebind_t = flat_adaptor_getter<E, L>;
static type get_flat_storage(reference e)
{
// moved to addressof because ampersand on xview returns a closure pointer
return type(std::addressof(e));
}
static auto get_offset(reference)
{
return typename std::decay_t<CT>::size_type(0);
}
static auto get_strides(reference e)
{
dynamic_shape<std::ptrdiff_t> strides;
strides.resize(e.shape().size());
compute_strides(e.shape(), L, strides);
return strides;
}
};
template <class CT, layout_type L>
using flat_storage_getter = std::conditional_t<
has_data_interface<std::decay_t<CT>>::value,
inner_storage_getter<CT>,
flat_adaptor_getter<CT, L>>;
template <layout_type L, class E>
inline auto get_offset(E& e)
{
return flat_storage_getter<E, L>::get_offset(e);
}
template <layout_type L, class E>
inline decltype(auto) get_strides(E& e)
{
return flat_storage_getter<E, L>::get_strides(e);
}
}
/*************************************
* xstrided_view_base implementation *
*************************************/
/**
* @name Constructor
*/
//@{
/**
* Constructs an xstrided_view_base
*
* @param e the underlying xexpression for this view
* @param shape the shape of the view
* @param strides the strides of the view
* @param offset the offset of the first element in the underlying container
* @param layout the layout of the view
*/
template <class D>
template <class CTA, class SA>
inline xstrided_view_base<D>::xstrided_view_base(
CTA&& e,
SA&& shape,
strides_type&& strides,
size_type offset,
layout_type layout
) noexcept
: m_e(std::forward<CTA>(e))
,
// m_storage(detail::get_flat_storage<undecay_expression>(m_e)),
m_storage(storage_getter::get_flat_storage(m_e))
, m_shape(std::forward<SA>(shape))
, m_strides(std::move(strides))
, m_offset(offset)
, m_layout(layout)
{
m_backstrides = xtl::make_sequence<backstrides_type>(m_shape.size(), 0);
adapt_strides(m_shape, m_strides, m_backstrides);
}
namespace detail
{
template <class T, class S>
auto& copy_move_storage(T& expr, const S& /*storage*/)
{
return expr.storage();
}
template <class T, class E, layout_type L>
auto copy_move_storage(T& expr, const detail::flat_expression_adaptor<E, L>& storage)
{
detail::flat_expression_adaptor<E, L> new_storage = storage; // copy storage
new_storage.update_pointer(std::addressof(expr));
return new_storage;
}
}
template <class D>
inline xstrided_view_base<D>::xstrided_view_base(xstrided_view_base&& rhs)
: base_type(std::move(rhs))
, m_e(std::forward<undecay_expression>(rhs.m_e))
, m_storage(detail::copy_move_storage(m_e, rhs.m_storage))
, m_shape(std::move(rhs.m_shape))
, m_strides(std::move(rhs.m_strides))
, m_backstrides(std::move(rhs.m_backstrides))
, m_offset(std::move(rhs.m_offset))
, m_layout(std::move(rhs.m_layout))
{
}
template <class D>
inline xstrided_view_base<D>::xstrided_view_base(const xstrided_view_base& rhs)
: base_type(rhs)
, m_e(rhs.m_e)
, m_storage(detail::copy_move_storage(m_e, rhs.m_storage))
, m_shape(rhs.m_shape)
, m_strides(rhs.m_strides)
, m_backstrides(rhs.m_backstrides)
, m_offset(rhs.m_offset)
, m_layout(rhs.m_layout)
{
}
//@}
/**
* @name Size and shape
*/
//@{
/**
* Returns the shape of the xtrided_view_base.
*/
template <class D>
inline auto xstrided_view_base<D>::shape() const noexcept -> const inner_shape_type&
{
return m_shape;
}
/**
* Returns the strides of the xtrided_view_base.
*/
template <class D>
inline auto xstrided_view_base<D>::strides() const noexcept -> const inner_strides_type&
{
return m_strides;
}
/**
* Returns the backstrides of the xtrided_view_base.
*/
template <class D>
inline auto xstrided_view_base<D>::backstrides() const noexcept -> const inner_backstrides_type&
{
return m_backstrides;
}
/**
* Returns the layout of the xtrided_view_base.
*/
template <class D>
inline auto xstrided_view_base<D>::layout() const noexcept -> layout_type
{
return m_layout;
}
template <class D>
inline bool xstrided_view_base<D>::is_contiguous() const noexcept
{
return m_layout != layout_type::dynamic && m_e.is_contiguous();
}
//@}
/**
* @name Data
*/
//@{
template <class D>
inline auto xstrided_view_base<D>::operator()() -> reference
{
return m_storage[static_cast<size_type>(m_offset)];
}
template <class D>
inline auto xstrided_view_base<D>::operator()() const -> const_reference
{
return m_storage[static_cast<size_type>(m_offset)];
}
/**
* Returns a reference to the element at the specified position in the view.
* @param args a list of indices specifying the position in the view. Indices
* must be unsigned integers, the number of indices should be equal or greater than
* the number of dimensions of the view.
*/
template <class D>
template <class... Args>
inline auto xstrided_view_base<D>::operator()(Args... args) -> reference
{
XTENSOR_TRY(check_index(shape(), args...));
XTENSOR_CHECK_DIMENSION(shape(), args...);
offset_type index = compute_index(args...);
return m_storage[static_cast<size_type>(index)];
}
/**
* Returns a constant reference to the element at the specified position in the view.
* @param args a list of indices specifying the position in the view. Indices
* must be unsigned integers, the number of indices should be equal or greater than
* the number of dimensions of the view.
*/
template <class D>
template <class... Args>
inline auto xstrided_view_base<D>::operator()(Args... args) const -> const_reference
{
XTENSOR_TRY(check_index(shape(), args...));
XTENSOR_CHECK_DIMENSION(shape(), args...);
offset_type index = compute_index(args...);
return m_storage[static_cast<size_type>(index)];
}
/**
* Returns a reference to the element at the specified position in the view.
* @param args a list of indices specifying the position in the view. Indices
* must be unsigned integers, the number of indices must be equal to the number of
* dimensions of the view, else the behavior is undefined.
*
* @warning This method is meant for performance, for expressions with a dynamic
* number of dimensions (i.e. not known at compile time). Since it may have
* undefined behavior (see parameters), operator() should be preferred whenever
* it is possible.
* @warning This method is NOT compatible with broadcasting, meaning the following
* code has undefined behavior:
* @code{.cpp}
* xt::xarray<double> a = {{0, 1}, {2, 3}};
* xt::xarray<double> b = {0, 1};
* auto fd = a + b;
* double res = fd.uncheked(0, 1);
* @endcode
*/
template <class D>
template <class... Args>
inline auto xstrided_view_base<D>::unchecked(Args... args) -> reference
{
offset_type index = compute_unchecked_index(args...);
return m_storage[static_cast<size_type>(index)];
}
/**
* Returns a constant reference to the element at the specified position in the view.
* @param args a list of indices specifying the position in the view. Indices
* must be unsigned integers, the number of indices must be equal to the number of
* dimensions of the view, else the behavior is undefined.
*
* @warning This method is meant for performance, for expressions with a dynamic
* number of dimensions (i.e. not known at compile time). Since it may have
* undefined behavior (see parameters), operator() should be preferred whenever
* it is possible.
* @warning This method is NOT compatible with broadcasting, meaning the following
* code has undefined behavior:
* @code{.cpp}
* xt::xarray<double> a = {{0, 1}, {2, 3}};
* xt::xarray<double> b = {0, 1};
* auto fd = a + b;
* double res = fd.uncheked(0, 1);
* @endcode
*/
template <class D>
template <class... Args>
inline auto xstrided_view_base<D>::unchecked(Args... args) const -> const_reference
{
offset_type index = compute_unchecked_index(args...);
return m_storage[static_cast<size_type>(index)];
}
/**
* Returns a reference to the element at the specified position in the view.
* @param first iterator starting the sequence of indices
* @param last iterator ending the sequence of indices
* The number of indices in the sequence should be equal to or greater than the the number
* of dimensions of the view..
*/
template <class D>
template <class It>
inline auto xstrided_view_base<D>::element(It first, It last) -> reference
{
XTENSOR_TRY(check_element_index(shape(), first, last));
return m_storage[static_cast<size_type>(compute_element_index(first, last))];
}
/**
* Returns a constant reference to the element at the specified position in the view.
* @param first iterator starting the sequence of indices
* @param last iterator ending the sequence of indices
* The number of indices in the sequence should be equal to or greater than the the number
* of dimensions of the view..
*/
template <class D>
template <class It>
inline auto xstrided_view_base<D>::element(It first, It last) const -> const_reference
{
XTENSOR_TRY(check_element_index(shape(), first, last));
return m_storage[static_cast<size_type>(compute_element_index(first, last))];
}
/**
* Returns a reference to the buffer containing the elements of the view.
*/
template <class D>
inline auto xstrided_view_base<D>::storage() noexcept -> storage_type&
{
return m_storage;
}
/**
* Returns a constant reference to the buffer containing the elements of the view.
*/
template <class D>
inline auto xstrided_view_base<D>::storage() const noexcept -> const storage_type&
{
return m_storage;
}
/**
* Returns a pointer to the underlying array serving as element storage.
* The first element of the view is at data() + data_offset().
*/
template <class D>
template <class E, class ST>
inline auto xstrided_view_base<D>::data() noexcept
-> std::enable_if_t<detail::provides_data_interface<E, ST>::value, pointer>
{
return m_e.data();
}
/**
* Returns a constant pointer to the underlying array serving as element storage.
* The first element of the view is at data() + data_offset().
*/
template <class D>
template <class E, class ST>
inline auto xstrided_view_base<D>::data() const noexcept
-> std::enable_if_t<detail::provides_data_interface<E, ST>::value, const_pointer>
{
return m_e.data();
}
/**
* Returns the offset to the first element in the view.
*/
template <class D>
inline auto xstrided_view_base<D>::data_offset() const noexcept -> size_type
{
return m_offset;
}
/**
* Returns a reference to the underlying expression of the view.
*/
template <class D>
inline auto xstrided_view_base<D>::expression() noexcept -> xexpression_type&
{
return m_e;
}
/**
* Returns a constant reference to the underlying expression of the view.
*/
template <class D>
inline auto xstrided_view_base<D>::expression() const noexcept -> const xexpression_type&
{
return m_e;
}
//@}
/**
* @name Broadcasting
*/
//@{
/**
* Broadcast the shape of the view to the specified parameter.
* @param shape the result shape
* @param reuse_cache parameter for internal optimization
* @return a boolean indicating whether the broadcasting is trivial
*/
template <class D>
template <class O>
inline bool xstrided_view_base<D>::broadcast_shape(O& shape, bool) const
{
return xt::broadcast_shape(m_shape, shape);
}
/**
* Checks whether the xstrided_view_base can be linearly assigned to an expression
* with the specified strides.
* @return a boolean indicating whether a linear assign is possible
*/
template <class D>
template <class O>
inline bool xstrided_view_base<D>::has_linear_assign(const O& str) const noexcept
{
return has_data_interface<xexpression_type>::value && str.size() == strides().size()
&& std::equal(str.cbegin(), str.cend(), strides().begin());
}
//@}
template <class D>
template <class... Args>
inline auto xstrided_view_base<D>::compute_index(Args... args) const -> offset_type
{
return static_cast<offset_type>(m_offset)
+ xt::data_offset<offset_type>(strides(), static_cast<offset_type>(args)...);
}
template <class D>
template <class... Args>
inline auto xstrided_view_base<D>::compute_unchecked_index(Args... args) const -> offset_type
{
return static_cast<offset_type>(m_offset)
+ xt::unchecked_data_offset<offset_type>(strides(), static_cast<offset_type>(args)...);
}
template <class D>
template <class It>
inline auto xstrided_view_base<D>::compute_element_index(It first, It last) const -> offset_type
{
return static_cast<offset_type>(m_offset) + xt::element_offset<offset_type>(strides(), first, last);
}
template <class D>
void xstrided_view_base<D>::set_offset(size_type offset)
{
m_offset = offset;
}
/******************************************
* flat_expression_adaptor implementation *
******************************************/
namespace detail
{
template <class CT, layout_type L>
inline flat_expression_adaptor<CT, L>::flat_expression_adaptor(CT* e)
: m_e(e)
{
resize_container(get_index(), m_e->dimension());
resize_container(m_strides, m_e->dimension());
m_size = compute_size(m_e->shape());
compute_strides(m_e->shape(), L, m_strides);
}
template <class CT, layout_type L>
template <class FST>
inline flat_expression_adaptor<CT, L>::flat_expression_adaptor(CT* e, FST&& strides)
: m_e(e)
, m_strides(xtl::forward_sequence<inner_strides_type, FST>(strides))
{
resize_container(get_index(), m_e->dimension());
m_size = m_e->size();
}
template <class CT, layout_type L>
inline void flat_expression_adaptor<CT, L>::update_pointer(CT* ptr) const
{
m_e = ptr;
}
template <class CT, layout_type L>
inline auto flat_expression_adaptor<CT, L>::size() const -> size_type
{
return m_size;
}
template <class CT, layout_type L>
inline auto flat_expression_adaptor<CT, L>::operator[](size_type idx) -> reference
{
auto i = static_cast<typename index_type::value_type>(idx);
get_index() = detail::unravel_noexcept(i, m_strides, L);
return m_e->element(get_index().cbegin(), get_index().cend());
}
template <class CT, layout_type L>
inline auto flat_expression_adaptor<CT, L>::operator[](size_type idx) const -> const_reference
{
auto i = static_cast<typename index_type::value_type>(idx);
get_index() = detail::unravel_noexcept(i, m_strides, L);
return m_e->element(get_index().cbegin(), get_index().cend());
}
template <class CT, layout_type L>
inline auto flat_expression_adaptor<CT, L>::begin() -> iterator
{
return m_e->template begin<L>();
}
template <class CT, layout_type L>
inline auto flat_expression_adaptor<CT, L>::end() -> iterator
{
return m_e->template end<L>();
}
template <class CT, layout_type L>
inline auto flat_expression_adaptor<CT, L>::begin() const -> const_iterator
{
return m_e->template cbegin<L>();
}
template <class CT, layout_type L>
inline auto flat_expression_adaptor<CT, L>::end() const -> const_iterator
{
return m_e->template cend<L>();
}
template <class CT, layout_type L>
inline auto flat_expression_adaptor<CT, L>::cbegin() const -> const_iterator
{
return m_e->template cbegin<L>();
}
template <class CT, layout_type L>
inline auto flat_expression_adaptor<CT, L>::cend() const -> const_iterator
{
return m_e->template cend<L>();
}
template <class CT, layout_type L>
inline auto flat_expression_adaptor<CT, L>::get_index() -> index_type&
{
thread_local static index_type index;
return index;
}
}
/**********************************
* Builder helpers implementation *
**********************************/
namespace detail
{
template <class S>
struct slice_getter_impl
{
const S& m_shape;
mutable std::size_t idx;
using array_type = std::array<std::ptrdiff_t, 3>;
explicit slice_getter_impl(const S& shape)
: m_shape(shape)
, idx(0)
{
}
template <class T>
array_type operator()(const T& /*t*/) const
{
return array_type{{0, 0, 0}};
}
template <class A, class B, class C>
array_type operator()(const xrange_adaptor<A, B, C>& range) const
{
auto sl = range.get(static_cast<std::size_t>(m_shape[idx]));
return array_type({sl(0), sl.size(), sl.step_size()});
}
template <class T>
array_type operator()(const xrange<T>& range) const
{
return array_type({range(T(0)), range.size(), T(1)});
}
template <class T>
array_type operator()(const xstepped_range<T>& range) const
{
return array_type({range(T(0)), range.size(), range.step_size(T(0))});
}
};
template <class adj_strides_policy>
struct strided_view_args : adj_strides_policy
{
using base_type = adj_strides_policy;
template <class S, class ST, class V>
void
fill_args(const S& shape, ST&& old_strides, std::size_t base_offset, layout_type layout, const V& slices)
{
// Compute dimension
std::size_t dimension = shape.size(), n_newaxis = 0, n_add_all = 0;
std::ptrdiff_t dimension_check = static_cast<std::ptrdiff_t>(shape.size());
bool has_ellipsis = false;
for (const auto& el : slices)
{
if (xtl::get_if<xt::xnewaxis_tag>(&el) != nullptr)
{
++dimension;
++n_newaxis;
}
else if (xtl::get_if<std::ptrdiff_t>(&el) != nullptr)
{
--dimension;
--dimension_check;
}
else if (xtl::get_if<xt::xellipsis_tag>(&el) != nullptr)
{
if (has_ellipsis == true)
{
XTENSOR_THROW(std::runtime_error, "Ellipsis can only appear once.");
}
has_ellipsis = true;
}
else
{
--dimension_check;
}
}
if (dimension_check < 0)
{
XTENSOR_THROW(std::runtime_error, "Too many slices for view.");
}
if (has_ellipsis)
{
// replace ellipsis with N * xt::all
// remove -1 because of the ellipsis slize itself
n_add_all = shape.size() - (slices.size() - 1 - n_newaxis);
}
// Compute strided view
new_offset = base_offset;
new_shape.resize(dimension);
new_strides.resize(dimension);
base_type::resize(dimension);
auto old_shape = shape;
using old_strides_value_type = typename std::decay_t<ST>::value_type;
std::ptrdiff_t axis_skip = 0;
std::size_t idx = 0, i = 0, i_ax = 0;
auto slice_getter = detail::slice_getter_impl<S>(shape);
for (; i < slices.size(); ++i)
{
i_ax = static_cast<std::size_t>(static_cast<std::ptrdiff_t>(i) - axis_skip);
auto ptr = xtl::get_if<std::ptrdiff_t>(&slices[i]);
if (ptr != nullptr)
{
auto slice0 = static_cast<old_strides_value_type>(*ptr);
new_offset += static_cast<std::size_t>(slice0 * old_strides[i_ax]);
}
else if (xtl::get_if<xt::xnewaxis_tag>(&slices[i]) != nullptr)
{
new_shape[idx] = 1;
base_type::set_fake_slice(idx);
++axis_skip, ++idx;
}
else if (xtl::get_if<xt::xellipsis_tag>(&slices[i]) != nullptr)
{
for (std::size_t j = 0; j < n_add_all; ++j)
{
new_shape[idx] = old_shape[i_ax];
new_strides[idx] = old_strides[i_ax];
base_type::set_fake_slice(idx);
++idx, ++i_ax;
}
axis_skip = axis_skip - static_cast<std::ptrdiff_t>(n_add_all) + 1;
}
else if (xtl::get_if<xt::xall_tag>(&slices[i]) != nullptr)
{
new_shape[idx] = old_shape[i_ax];
new_strides[idx] = old_strides[i_ax];
base_type::set_fake_slice(idx);
++idx;
}
else if (base_type::fill_args(slices, i, idx, old_shape[i_ax], old_strides[i_ax], new_shape, new_strides))
{
++idx;
}
else
{
slice_getter.idx = i_ax;
auto info = xtl::visit(slice_getter, slices[i]);
new_offset += static_cast<std::size_t>(info[0] * old_strides[i_ax]);
new_shape[idx] = static_cast<std::size_t>(info[1]);
new_strides[idx] = info[2] * old_strides[i_ax];
base_type::set_fake_slice(idx);
++idx;
}
}
i_ax = static_cast<std::size_t>(static_cast<std::ptrdiff_t>(i) - axis_skip);
for (; i_ax < old_shape.size(); ++i_ax, ++idx)
{
new_shape[idx] = old_shape[i_ax];
new_strides[idx] = old_strides[i_ax];
base_type::set_fake_slice(idx);
}
new_layout = do_strides_match(new_shape, new_strides, layout, true) ? layout
: layout_type::dynamic;
}
using shape_type = dynamic_shape<std::size_t>;
shape_type new_shape;
using strides_type = dynamic_shape<std::ptrdiff_t>;
strides_type new_strides;
std::size_t new_offset;
layout_type new_layout;
};
}
}
#endif
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