`ScatterView`#

Header File: <Kokkos_ScatterView.hpp>

Description#

template<typename DataType, int Op, typename ExecSpace, typename Layout, int contribution> class ScatterView#

Public Member Variables

original_view_type#: Type of View passed to ScatterView constructor.

original_value_type#: Value type of the original_view_type.

original_reference_type#: Reference type of the original_view_type.

data_type_info#: DuplicatedDataType, a newly created DataType that has a new runtime dimension which becomes the largest-stride dimension, from the given View DataType.

internal_data_type#: Value type of data_type_info.

internal_view_type#: A View type created from the internal_data_type.

Constructors

ScatterView()#: The default constructor. Default constructs members.

ScatterView(View<RT, RP...> const&)#: Constructor from a Kokkos::View. internal_view member is copy constructed from this input view.

ScatterView(std::string const &name, Dims... dims)#: Constructor from variadic pack of dimension arguments. Constructs internal_view member.

ScatterView(ALLOC_PROP const &arg_prop, Dims... dims)#: Constructor from variadic pack of dimension arguments. Constructs internal_view member. This constructor allows passing an object created by Kokkos::view_alloc as first argument, e.g., for specifying an execution space via Kokkos::view_alloc(exec_space, "label").

Public Methods

constexpr bool is_allocated() const#

Returns:: true if the internal_view points to a valid memory location. This function works for both managed and unmanaged views. With the unmanaged view, there is no guarantee that referenced address is valid, only that it is a non-null pointer.

access() const#: use within a kernel to return a ScatterAccess member; this member accumulates a given thread’s contribution to the reduction.

subview() const#

Returns:: a subview of a ScatterView

contribute_into(View<DT, RP...> const &dest) const#: contribute ScatterView array’s results into the input View dest

reset()#: performs reset on destination array

reset_except(View<DT, RP...> const &view)#: tbd

resize(const size_t n0 = 0, const size_t n1 = 0, const size_t n2 = 0, const size_t n3 = 0, const size_t n4 = 0, const size_t n5 = 0, const size_t n6 = 0, const size_t n7 = 0)#: resize a view with copying old data to new data at the corresponding indices

realloc(const size_t n0 = 0, const size_t n1 = 0, const size_t n2 = 0, const size_t n3 = 0, const size_t n4 = 0, const size_t n5 = 0, const size_t n6 = 0, const size_t n7 = 0)#: resize a view with discarding old data

Private Members

Member:: typedef original_view_type internal_view_type;
Member:: internal_view_type internal_view;

Free Functions

contribute(View<DT1, VP...> &dest, Kokkos::Experimental::ScatterView<DT2, LY, ES, OP, CT, DP> const &src)#: convenience function to perform final reduction of ScatterView results into a resultant View; may be called following parallel_reduce().

Example#

KOKKOS_INLINE_FUNCTION int foo(int i) { return i; }
KOKKOS_INLINE_FUNCTION double bar(int i) { return i*i; }

Kokkos::View<double*> results("results", 1);
Kokkos::Experimental::ScatterView<double*> scatter(results);
Kokkos::parallel_for(1, KOKKOS_LAMBDA(int input_i) {
    auto access = scatter.access();
    auto result_i = foo(input_i);
    auto contribution = bar(input_i);
    access(result_i) += contribution;
});
Kokkos::Experimental::contribute(results, scatter);