Concept definition

template<typename SU, typename TF, typename G>
concept stencil::concepts::StencilUpdate = 
    
    requires(SU stencil_update, G &grid, typename SU::Params params) {
        { SU(params) } -> std::same_as<SU>;
        { stencil_update.get_params() } -> std::same_as<typename SU::Params &>;
        { stencil_update(grid) } -> std::same_as<G>;
    } &&
    
    requires(typename SU::Params params) {
        { params.transition_function } -> std::same_as<TF &>;
        { params.halo_value } -> std::same_as<typename TF::Cell &>;
        { params.iteration_offset } -> std::same_as<uindex_t &>;
        { params.n_iterations } -> std::same_as<uindex_t &>;
        { params.device } -> std::same_as<sycl::device &>;
    } && TransitionFunction<TF> && Grid<G, typename TF::Cell> &&
    (std::is_class<typename SU::Params>::value)

Detailed Description

A grid updater that repeatedly applies stencil updates to each cell.

Template Parameters

TF	The transition function type, which must satisfy the TransitionFunction concept.
G	The grid type the updater operates on. It must satisfy the Grid concept.

The constructor of a stencil update must accept a parameter struct instance. This struct must be (re-)defined inside the class as Params, and must contain the following fields. Where a default value is given, this default value must be provided. Additional parameter fields may be added as needed.

TF transition_function: The transition function instance to use.
TF::Cell halo_value = TF::Cell(): The default value for cells outside of the actual grid.
uindex_t iteration_offset = 0: The starting iteration index of the input grid.
uindex_t n_iterations = 0: The number of iterations to compute. The iteration index of the output grid will be iteration_offset + n_iterations.
sycl::device device = sycl::device(): The SYCL device to use for computations.

Each updater must define the following methods:

SU(SU::Params params): Create a new stencil update object using the given parameters.
SU::Params &get_params(): Get the reference to the current parameter configuration. Changed parameter fields must be used the next time operator() is called.
G operator()(Grid input_grid): Create a new, updated version of the input_grid. The input_grid must not be modified.