Omega_h_dist.hpp

#ifndef OMEGA_H_DIST_HPP
#define OMEGA_H_DIST_HPP
 
#include <Omega_h_comm.hpp>
#include <Omega_h_remotes.hpp>
#include <Omega_h_graph.hpp>
 
/* \file Omega_h_dist.hpp
  \brief Header file for Omega_h::Dist
 */
 
namespace Omega_h {
 
class Dist {
  CommPtr parent_comm_;
  LOs roots2items_[2];
  LOs items2content_[2];
  LOs msgs2content_[2];
  CommPtr comm_[2];
 
 public:
  Dist();
  Dist(Dist const& other);
  Dist& operator=(Dist const& other);
  Dist(CommPtr comm_in, Remotes fitems2rroots, LO nrroots);
  void set_parent_comm(CommPtr parent_comm_in);
  /* set the destination graph node MPI ranks of the "items"
     (graph edges sorted by local source node).
     this call defines the majority of the communication pattern,
     including neighbors and forwards items2content permutation.
     this is a collective call.
   */
  void set_dest_ranks(Read<I32> items2ranks_in);
  /* optionally set the destination root (local) indices of
     each forward item. one also needs to specify the number
     of destination roots on this MPI rank.
     this will specify the receiving side of the data
     structure, including items2content and roots2items.
     if not specified, then destination content, items,
     and roots will all be assumed to be the same.
   */
  void set_dest_idxs(LOs fitems2rroots, LO nrroots);
  /* optionally specify the expansion ("fan") from forward
     roots to items.
     if not specified, forward roots and items will be assumed
     to be the same. */
  void set_roots2items(LOs froots2fitems);
  /* optionally specify the _global_ numbers of the destination
     graph nodes of each forward item.
     this will define the reverse items (items2content) by
     insisting that these items be sorted in ascending order
     of their global number.
     reverse roots are not specified by this function, they
     are assumed to be the same as reverse items.
     one may only call this API or set_dest_idxs(), not both */
  void set_dest_globals(GOs fitems2ritem_globals);
  Dist invert() const;
  template <typename T>
  Read<T> exch(Read<T> data, Int width) const;
  template <typename T>
  Future<T> iexch(Read<T> data, Int width) const;
  template <typename T>
  Read<T> exch_reduce(Read<T> data, Int width, Omega_h_Op op) const;
  CommPtr parent_comm() const;
  CommPtr comm() const;
  LOs msgs2content() const;
  LOs content2msgs() const;
  LOs items2content() const;
  LOs items2msgs() const;
  LOs roots2items() const;
  Read<I32> msgs2ranks() const;
  Read<I32> items2ranks() const;
  LOs items2dest_idxs() const;
  Remotes items2dests() const;
  LO nitems() const;
  LO nroots() const;
  LO ndests() const;
  LO nsrcs() const;
  void change_comm(CommPtr new_comm);
  Remotes exch(Remotes data, Int width) const;
 
 private:
  void copy(Dist const& other);
  enum { F, R };
};
 
Dist create_dist_for_variable_sized(Dist copies2owners, LOs copies2data);
 
#define OMEGA_H_EXPL_INST_DECL(T)                                              \
  extern template Read<T> Dist::exch(Read<T> data, Int width) const;           \
  extern template Future<T> Dist::iexch(Read<T> data, Int width) const;        \
  extern template Read<T> Dist::exch_reduce<T>(                                \
      Read<T> data, Int width, Omega_h_Op op) const;
OMEGA_H_EXPL_INST_DECL(I8)
OMEGA_H_EXPL_INST_DECL(I32)
OMEGA_H_EXPL_INST_DECL(I64)
OMEGA_H_EXPL_INST_DECL(Real)
#undef OMEGA_H_EXPL_INST_DECL
 
}  // namespace Omega_h
 
#endif