Kokkos::create_mirror

Kokkos::create_mirror[_view]

Header File: Kokkos_Core.hpp

A common desired use case is to have a memory allocation in GPU memory and an identical memory allocation in CPU memory, such that copying from one to another is straightforward. To satisfy this use case and others, Kokkos has facilities for dealing with "mirrors" of View. A "mirror" of a View type A is loosely defined a View type B such that Views of type B are accessible from the CPU and deep_copy between Views of type A and B are direct. The most common functions for dealing with mirrors are create_mirror, create_mirror_view and create_mirror_view_and_copy.

Usage:

auto host_mirror = create_mirror(a_view);
auto host_mirror_view = create_mirror_view(a_view);

auto host_mirror_space = create_mirror(ExecSpace(),a_view);
auto host_mirror_view_space = create_mirror_view(ExecSpace(),a_view);

Synopsis

template <class ViewType>
typename ViewType::HostMirror create_mirror(ViewType const&);

template <class ViewType>
typename ViewType::HostMirror create_mirror(decltype(Kokkos::ViewAllocateWithoutInitializing(), 
                                            ViewType const&);

template <class Space, class ViewType>
ImplMirrorType create_mirror(Space const& space, ViewType const&);

template <class Space, class ViewType>
ImplMirrorType create_mirror(decltype(Kokkos::ViewAllocateWithoutInitializing(),
                             Space const& space, ViewType const&);

template <class ViewType>
typename ViewType::HostMirror create_mirror_view(ViewType const&);

template <class ViewType>
typename ViewType::HostMirror create_mirror_view(decltype(Kokkos::ViewAllocateWithoutInitializing(),
                                                 ViewType const&);

template <class Space, class ViewType>
ImplMirrorType create_mirror_view(Space const& space, ViewType const&);

template <class Space, class ViewType>
ImplMirrorType create_mirror_view(decltype(Kokkos::ViewAllocateWithoutInitializing(),
                                  Space const& space, ViewType const&);

template <class Space, class ViewType>
ImplMirrorType create_mirror_view_and_copy(Space const& space, ViewType const&);

Description

• template <class ViewType>
  typename ViewType::HostMirror create_mirror(ViewType const& src);

  Creates a new host accessible View with the same layout and padding as src.

  • src: a Kokkos::View.

• template <class ViewType>
  typename ViewType::HostMirror create_mirror(decltype(Kokkos::ViewAllocateWithoutInitializing()),
                                              ViewType const& src);

  Creates a new host accessible View with the same layout and padding as src. The new view will have unitialized data.

  • src: a Kokkos::View.

• template <class Space, class ViewType>
  ImplMirrorType create_mirror(Space const& space, ViewType const&);

  Creates a new View with the same layout and padding as src but with a device type of Space::device_type.

  • src: a Kokkos::View.
  • Space: a class meeting the requirements of ExecutionSpaceConcept or MemorySpaceConcept
  • ImplMirrorType: an implementation defined specialization of Kokkos::View.

• template <class Space, class ViewType>
  ImplMirrorType create_mirror(decltype(Kokkos::ViewAllocateWithoutInitializing()),
                               Space const& space, ViewType const&);

  Creates a new View with the same layout and padding as src but with a device type of Space::device_type. The new view will have unitialized data.

  • src: a Kokkos::View.
  • Space: a class meeting the requirements of ExecutionSpaceConcept or MemorySpaceConcept
  • ImplMirrorType: an implementation defined specialization of Kokkos::View.

• template <class ViewType>
  typename ViewType::HostMirror create_mirror_view(ViewType const& src);

  If src is not host accessible (i.e. if SpaceAccessibility<HostSpace,ViewType::memory_space>::accessible is false) it creates a new host accessible View with the same layout and padding as src. Otherwise returns src.

  • src: a Kokkos::View.

• template <class ViewType>
  typename ViewType::HostMirror create_mirror_view(decltype(Kokkos::ViewAllocateWithoutInitializing()),
                                                   ViewType const& src);

  If src is not host accessible (i.e. if SpaceAccessibility<HostSpace,ViewType::memory_space>::accessible is false) it creates a new host accessible View with the same layout and padding as src. The new view will have unitialized data. Otherwise returns src.

  • src: a Kokkos::View.

• template <class Space, class ViewType>
  ImplMirrorType create_mirror_view(Space const& space, ViewType const&);

  If std::is_same<typename Space::memory_space, typename ViewType::memory_space>::value is false, creates a new View with the same layout and padding as src but with a device type of Space::device_type. Otherwise returns src.

  • src: a Kokkos::View.
  • Space: a class meeting the requirements of ExecutionSpaceConcept or MemorySpaceConcept
  • ImplMirrorType: an implementation defined specialization of Kokkos::View.

• template <class Space, class ViewType>
  ImplMirrorType create_mirror_view(decltype(Kokkos::ViewAllocateWithoutInitializing(), 
                                    Space const& space, ViewType const&);

  If std::is_same<typename Space::memory_space, typename ViewType::memory_space>::value is false, creates a new View with the same layout and padding as src but with a device type of Space::device_type. The new view will have unitialized data. Otherwise returns src.

  • src: a Kokkos::View.
  • Space: a class meeting the requirements of ExecutionSpaceConcept or MemorySpaceConcept
  • ImplMirrorType: an implementation defined specialization of Kokkos::View.

• template <class Space, class ViewType>
  ImplMirrorType create_mirror_view_and_copy(Space const& space, ViewType const&);

  If std::is_same<typename Space::memory_space, typename ViewType::memory_space>::value is false, creates a new Kokkos::View with the same layout and padding as src but with a device type of Space::device_type and conducts a deep_copy from src to the new view if one was created. Otherwise returns src.

  • src: a Kokkos::View.
  • Space: a class meeting the requirements of ExecutionSpaceConcept or MemorySpaceConcept
  • ImplMirrorType: an implementation defined specialization of Kokkos::View.