Concept definition

        template<typename T, typename T_Mut, typename T_Const>
        concept IMdSpan = requires(T t, T_Mut mut_t, T_Const const_t, alpaka::Vec<typename T::index_type, T::dim()> vec) {
                  requires IDataSource<T>;
 
                  typename T::reference;
                  typename T::const_reference;
                  typename T::pointer;
                  typename T::const_pointer;
 
                  { *mut_t } -> std::same_as<typename T::reference>;
                  { *const_t } -> std::same_as<typename T::const_reference>;
                  { mut_t.data() } -> std::same_as<typename T::pointer>;
                  { const_t.data() } -> std::same_as<typename T::const_pointer>;
 
                  { mut_t[vec] } -> std::same_as<typename T::reference>;
                  { const_t[vec] } -> std::same_as<typename T::const_reference>;
                  // only if MdSpan like object is 1D, the access operator with an integral is available
                  requires(T::dim() != 1u) || (T::dim() == 1u && requires {
                              { mut_t[typename T::index_type{0}] } -> std::same_as<typename T::reference>;
                          });
                  requires(T::dim() != 1u) || (T::dim() == 1u && requires {
                              { const_t[typename T::index_type{0}] } -> std::same_as<typename T::const_reference>;
                          });

Todo: add getSlice, getConstSlice and getView, getConstView functions

}

Detailed Description

Interface concept for objects describing multidimensional memory access.

An object of type alpaka::mdspan does not store any information about the storage location, e.g., whether the memory is located on a CPU or a GPU. The interface corresponds to that of a standard library container with continuous memory, but has some differences to support multidimensional memory. For example, instead of the member function size(), which returns the 1D size, alpaka::mdspan like objects provides the function getExtents(), which returns the size of each dimension.

Parameters

t	Object of type alpaka::mdspan. May or may not have a const modifier.
mut_t	Mutable object of type alpaka::mdspan. Does not have a const modifier.
const_t	Constant object of type alpaka::mdspan. Does have a const modifier.
vec	Vector with the same number of elements as the dimension of the alpaka::mdspan like object. Used to call the access operator.

Components

An alpaka::mdspan like object contains 4 components:

A pointer to the actual memory.
An extents object that describes the number of dimensions and their respective sizes.
A pitch object that specifies how many bytes are required to jump to the next element in each dimension.
An alignment object that describes how the elements are aligned in memory, see: alpaka::concepts::Alignment

Member types

T::reference: The element reference type is either const or non-const, depending on T::value_type.
T::const_reference: The constant reference type for an element. Always const.
T::pointer: The element pointer type is either const or non-const, depending on T::value_type.
T::const_pointer: The constant pointer type for an element. Always pointer-to-const.

Definition at line 53 of file IMdSpan.hpp.