Ifpack2_MDF_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_MDF_DECL_HPP
#define IFPACK2_MDF_DECL_HPP

#include "Ifpack2_Preconditioner.hpp"
#include "Ifpack2_Details_CanChangeMatrix.hpp"
#include "Tpetra_CrsMatrix_decl.hpp"
#include "Ifpack2_ScalingType.hpp"
#include "Ifpack2_IlukGraph.hpp"
#include "Ifpack2_LocalSparseTriangularSolver_decl.hpp"
#include "KokkosSparse_mdf.hpp"

#include <type_traits>

namespace Teuchos {
  class ParameterList; // forward declaration
}
namespace Ifpack2 {

template<class MatrixType>
class MDF:
    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 Teuchos::ScalarTraits<scalar_type>::magnitudeType magnitude_type;

  typedef typename node_type::device_type device_type;

  typedef typename node_type::execution_space execution_space;

  typedef Tpetra::RowMatrix<scalar_type,
                            local_ordinal_type,
                            global_ordinal_type,
                            node_type> row_matrix_type;


  static_assert(std::is_same<MatrixType, row_matrix_type>::value, "Ifpack2::MDF: The template parameter MatrixType must be a Tpetra::RowMatrix specialization.  Please don't use Tpetra::CrsMatrix (a subclass of Tpetra::RowMatrix) here anymore.");

  typedef Tpetra::CrsMatrix<scalar_type,
                            local_ordinal_type,
                            global_ordinal_type,
                            node_type> crs_matrix_type;

  typedef typename crs_matrix_type::impl_scalar_type impl_scalar_type;

  template <class NewMatrixType> friend class MDF;

  typedef typename crs_matrix_type::global_inds_host_view_type global_inds_host_view_type;
  typedef typename crs_matrix_type::local_inds_host_view_type local_inds_host_view_type;
  typedef typename crs_matrix_type::values_host_view_type values_host_view_type;


  typedef typename crs_matrix_type::nonconst_global_inds_host_view_type nonconst_global_inds_host_view_type;
  typedef typename crs_matrix_type::nonconst_local_inds_host_view_type nonconst_local_inds_host_view_type;
  typedef typename crs_matrix_type::nonconst_values_host_view_type nonconst_values_host_view_type;




  typedef typename crs_matrix_type::local_matrix_device_type local_matrix_device_type;
  typedef typename local_matrix_device_type::StaticCrsGraphType::row_map_type lno_row_view_t;
  typedef typename local_matrix_device_type::StaticCrsGraphType::entries_type lno_nonzero_view_t;
  typedef typename local_matrix_device_type::values_type scalar_nonzero_view_t;
  typedef typename local_matrix_device_type::StaticCrsGraphType::device_type::memory_space TemporaryMemorySpace;
  typedef typename local_matrix_device_type::StaticCrsGraphType::device_type::memory_space PersistentMemorySpace;
  typedef typename local_matrix_device_type::StaticCrsGraphType::device_type::execution_space HandleExecSpace;
  typedef 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 > kk_handle_type;
  
  MDF (const Teuchos::RCP<const row_matrix_type>& A_in);

  MDF (const Teuchos::RCP<const crs_matrix_type>& A_in);

 private:
  MDF (const MDF<MatrixType> & src);

 public:
  virtual ~MDF () = default;

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

  void initialize ();

  void compute ();

  bool isInitialized () const {
    return isInitialized_;
  }
  bool isComputed () const {
    return isComputed_;
  }

  int getNumInitialize () const {
    return numInitialize_;
  }
  int getNumCompute () const {
    return numCompute_;
  }
  int getNumApply () const {
    return numApply_;
  }

  double getInitializeTime () const {
    return initializeTime_;
  }
  double getComputeTime () const {
    return computeTime_;
  }
  double getApplyTime () const {
    return applyTime_;
  }

  size_t getNodeSmootherComplexity() const;  



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



  std::string description () const;



  Teuchos::RCP<const Tpetra::Map<local_ordinal_type,global_ordinal_type,node_type> >
  getDomainMap () const;

  Teuchos::RCP<const Tpetra::Map<local_ordinal_type,global_ordinal_type,node_type> >
  getRangeMap () const;

  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;

private:

  // Split off to a different impl call so that nested apply calls don't mess up apply counts/timers
  void apply_impl (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;

  void
  multiply (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,
            const Teuchos::ETransp mode = Teuchos::NO_TRANS) const;
public:
  using MDF_handle_device_type = KokkosSparse::Experimental::MDF_handle<local_matrix_device_type>;
  using permutations_type = Teuchos::ArrayRCP<local_ordinal_type>;

  Teuchos::RCP<const row_matrix_type> getMatrix () const;

  int getLevelOfFill () const { return LevelOfFill_; }

  Tpetra::CombineMode getOverlapMode () {
    TEUCHOS_TEST_FOR_EXCEPTION(
      true, std::logic_error, "Ifpack2::MDF::SetOverlapMode: "
      "MDF no longer implements overlap on its own.  "
      "Use MDF with AdditiveSchwarz if you want overlap.");
  }

  Tpetra::global_size_t getGlobalNumEntries () const {
    return getL ().getGlobalNumEntries () + getU ().getGlobalNumEntries ();
  }

  const crs_matrix_type& getL () const;

  const crs_matrix_type& getU () const;

  permutations_type & getPermutations() const;

  permutations_type & getReversePermutations() const;

  Teuchos::RCP<const crs_matrix_type> getCrsMatrix () const;

private:
  typedef Tpetra::MultiVector<scalar_type,local_ordinal_type,global_ordinal_type,node_type> MV;
  typedef Teuchos::ScalarTraits<scalar_type> STS;
  typedef Teuchos::ScalarTraits<magnitude_type> STM;

  void allocateSolvers ();
  void allocatePermutations(bool force = false);
  static void checkOrderingConsistency (const row_matrix_type& A);
  // void initAllValues (const row_matrix_type& A);

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

protected:
  typedef Tpetra::Vector<scalar_type,local_ordinal_type,global_ordinal_type,node_type> vec_type;

  Teuchos::RCP<const row_matrix_type> A_;

  // The MDF handle
  Teuchos::RCP<MDF_handle_device_type> MDF_handle_;

  Teuchos::RCP<const row_matrix_type> A_local_;
  lno_row_view_t A_local_rowmap_; 
  lno_nonzero_view_t A_local_entries_; 
  scalar_nonzero_view_t A_local_values_;

  Teuchos::RCP<crs_matrix_type> L_;
  Teuchos::RCP<LocalSparseTriangularSolver<row_matrix_type> > L_solver_;
  Teuchos::RCP<crs_matrix_type> U_;
  Teuchos::RCP<LocalSparseTriangularSolver<row_matrix_type> > U_solver_;

  permutations_type permutations_;

  permutations_type reversePermutations_;

  int Verbosity_;

  int LevelOfFill_;
  double Overalloc_;

  bool isAllocated_;
  bool isInitialized_;
  bool isComputed_;

  int numInitialize_;
  int numCompute_;
  mutable int numApply_;

  double initializeTime_;
  double computeTime_;
  mutable double applyTime_;
};

} // namespace Ifpack2

#endif /* IFPACK2_MDF_DECL_HPP */