Ifpack2_LocalSparseTriangularSolver_decl.hpp

// @HEADER
// *****************************************************************************
//       Ifpack2: Templated Object-Oriented Algebraic Preconditioner Package
//
// Copyright 2009 NTESS and the Ifpack2 contributors.
// SPDX-License-Identifier: BSD-3-Clause
// *****************************************************************************
// @HEADER

#ifndef IFPACK2_LOCALSPARSETRIANGULARSOLVER_DECL_HPP
#define IFPACK2_LOCALSPARSETRIANGULARSOLVER_DECL_HPP

#include "Ifpack2_Preconditioner.hpp"
#include "Ifpack2_Details_CanChangeMatrix.hpp"
#include "Tpetra_CrsMatrix_fwd.hpp"
#include "Teuchos_FancyOStream.hpp"
#include <type_traits>

#include "KokkosSparse_sptrsv.hpp"

namespace Ifpack2 {

template<class MatrixType>
class LocalSparseTriangularSolver :
    virtual public Ifpack2::Preconditioner<typename MatrixType::scalar_type,
                                           typename MatrixType::local_ordinal_type,
                                           typename MatrixType::global_ordinal_type,
                                           typename MatrixType::node_type>,
    virtual public Ifpack2::Details::CanChangeMatrix<Tpetra::RowMatrix<typename MatrixType::scalar_type,
                                                                       typename MatrixType::local_ordinal_type,
                                                                       typename MatrixType::global_ordinal_type,
                                                                       typename MatrixType::node_type> >
{
public:
  typedef typename MatrixType::scalar_type scalar_type;
  typedef typename MatrixType::local_ordinal_type local_ordinal_type;
  typedef typename MatrixType::global_ordinal_type global_ordinal_type;
  typedef typename MatrixType::node_type node_type;

  typedef typename MatrixType::mag_type magnitude_type;
  typedef Tpetra::Map<local_ordinal_type, global_ordinal_type, node_type> map_type;
  typedef Tpetra::RowMatrix<scalar_type, local_ordinal_type,
                            global_ordinal_type, node_type> row_matrix_type;
  typedef Tpetra::CrsMatrix<scalar_type, local_ordinal_type,
                            global_ordinal_type, node_type> crs_matrix_type;

  static_assert (std::is_same<MatrixType, row_matrix_type>::value,
                 "Ifpack2::LocalSparseTriangularSolver: The template parameter "
                 "MatrixType must be a Tpetra::RowMatrix specialization.  "
                 "Please don't use Tpetra::CrsMatrix (a subclass of "
                 "Tpetra::RowMatrix) here anymore.  The constructor can take "
                 "either a RowMatrix or a CrsMatrix just fine.");

  // Use the local matrix types
  using local_matrix_device_type = typename crs_matrix_type::local_matrix_device_type;
  using local_matrix_graph_device_type = typename local_matrix_device_type::StaticCrsGraphType;
  using lno_row_view_t = typename local_matrix_graph_device_type::row_map_type;
  using lno_nonzero_view_t = typename local_matrix_graph_device_type::entries_type;
  using scalar_nonzero_view_t = typename local_matrix_device_type::values_type;
  using TemporaryMemorySpace = typename local_matrix_graph_device_type::device_type::memory_space;
  using PersistentMemorySpace = typename local_matrix_graph_device_type::device_type::memory_space;
  using HandleExecSpace = typename local_matrix_graph_device_type::device_type::execution_space;
  using k_handle = typename KokkosKernels::Experimental::KokkosKernelsHandle<typename lno_row_view_t::const_value_type, typename lno_nonzero_view_t::const_value_type, typename scalar_nonzero_view_t::value_type, HandleExecSpace, TemporaryMemorySpace,PersistentMemorySpace >;

  LocalSparseTriangularSolver (const Teuchos::RCP<const row_matrix_type>& A);

  LocalSparseTriangularSolver (const Teuchos::RCP<const row_matrix_type>& A,
                               const Teuchos::RCP<Teuchos::FancyOStream>& out);

  LocalSparseTriangularSolver ();

  LocalSparseTriangularSolver (const bool /* unused */, const Teuchos::RCP<Teuchos::FancyOStream>& out);

  virtual ~LocalSparseTriangularSolver ();

  void setParameters (const Teuchos::ParameterList& params);

  void initialize ();

  inline bool isInitialized () const {
    return isInitialized_;
  }

  void compute ();

  inline bool isComputed () const {
    return isComputed_;
  }



  void
  apply (const Tpetra::MultiVector<scalar_type,local_ordinal_type,global_ordinal_type,node_type>& X,
         Tpetra::MultiVector<scalar_type,local_ordinal_type,global_ordinal_type,node_type>& Y,
         Teuchos::ETransp mode = Teuchos::NO_TRANS,
         scalar_type alpha = Teuchos::ScalarTraits<scalar_type>::one (),
         scalar_type beta = Teuchos::ScalarTraits<scalar_type>::zero ()) const;

  Teuchos::RCP<const map_type> getDomainMap () const;

  Teuchos::RCP<const map_type> getRangeMap () const;

  void
  applyMat (const Tpetra::MultiVector<scalar_type, local_ordinal_type,
              global_ordinal_type, node_type>& X,
            Tpetra::MultiVector<scalar_type, local_ordinal_type,
              global_ordinal_type, node_type>& Y,
            Teuchos::ETransp mode = Teuchos::NO_TRANS) const;

  Teuchos::RCP<const Teuchos::Comm<int> > getComm () const;

  Teuchos::RCP<const row_matrix_type> getMatrix () const {
    return A_;
  }

  double getComputeFlops () const;

  double getApplyFlops () const;

  int getNumInitialize () const;

  int getNumCompute () const;

  int getNumApply () const;

  double getInitializeTime () const;

  double getComputeTime () const;

  double getApplyTime () const;



  std::string description() const;

  void
  describe (Teuchos::FancyOStream& out,
            const Teuchos::EVerbosityLevel verbLevel =
            Teuchos::Describable::verbLevel_default) const;

  virtual void setMatrix (const Teuchos::RCP<const row_matrix_type>& A);

  void setStreamInfo (const bool& isKokkosKernelsStream, const int& num_streams, const std::vector<HandleExecSpace>& exec_space_instances);

  void setMatrices (const std::vector< Teuchos::RCP<crs_matrix_type> >& A_crs_v);


private:
  Teuchos::RCP<const row_matrix_type> A_;
  Teuchos::RCP<Teuchos::FancyOStream> out_;
  Teuchos::RCP<const crs_matrix_type> A_crs_;
  std::vector< Teuchos::RCP<crs_matrix_type> > A_crs_v_;

  typedef Tpetra::MultiVector<scalar_type, local_ordinal_type, global_ordinal_type, node_type> MV;
  mutable Teuchos::RCP<MV> X_colMap_;
  mutable Teuchos::RCP<MV> Y_rowMap_;

  bool isInitialized_;
  bool isComputed_;
  bool isInternallyChanged_;
  bool reverseStorage_;

  mutable int numInitialize_;
  mutable int numCompute_;
  mutable int numApply_;

  double initializeTime_;
  double computeTime_;
  double applyTime_;

  class HtsImpl;
  Teuchos::RCP<HtsImpl> htsImpl_;

  bool isKokkosKernelsSptrsv_;
  Teuchos::RCP<k_handle> kh_;
  std::vector< Teuchos::RCP<k_handle> > kh_v_;
  int num_streams_;
  bool isKokkosKernelsStream_;
  bool kh_v_nonnull_;
  std::vector<HandleExecSpace> exec_space_instances_;

  std::string uplo_;
  std::string diag_;

  void
  localApply (const MV& X,
              MV& Y,
              const Teuchos::ETransp mode,
              const scalar_type& alpha,
              const scalar_type& beta) const;

  void
  localTriangularSolve (const MV& Y,
                        MV& X,
                        const Teuchos::ETransp mode) const;

  void initializeState();

  KokkosSparse::Experimental::SPTRSVAlgorithm kokkosKernelsAlgorithm() const;
};

} // namespace Ifpack2

#endif // IFPACK2_LOCALSPARSETRIANGULARSOLVER_DECL_HPP