make_block_solver.h

// -*- tab-width: 2; indent-tabs-mode: nil; coding: utf-8-with-signature -*-
//-----------------------------------------------------------------------------
// Copyright 2000-2026 CEA (www.cea.fr) IFPEN (www.ifpenergiesnouvelles.com)
// See the top-level COPYRIGHT file for details.
// SPDX-License-Identifier: Apache-2.0
//-----------------------------------------------------------------------------
/*---------------------------------------------------------------------------*/
/*---------------------------------------------------------------------------*/
/*
 * This file is based on the work on AMGCL library (version march 2026)
 * which can be found at https://github.com/ddemidov/amgcl.
 *
 * Copyright (c) 2012-2022 Denis Demidov <dennis.demidov@gmail.com>
 * SPDX-License-Identifier: MIT
 */
/*---------------------------------------------------------------------------*/
/*---------------------------------------------------------------------------*/
 
#ifndef ARCCORE_ALINA_MAKE_BLOCK_SOLVER_HPP
#define ARCCORE_ALINA_MAKE_BLOCK_SOLVER_HPP
 
#include "arccore/alina/BackendInterface.h"
#include "arccore/alina/Adapters.h"
#include "arccore/alina/StaticMatrix.h"
#include "arccore/alina/PreconditionedSolver.h"
#include "arccore/alina/AlinaUtils.h"
 
namespace Arcane::Alina
{
 
/* Creates solver that operates in non-scalar domain but may take scalar inputs
 * for the system matrix and the rhs/solution vectors.
 */
template <class Precond, class IterativeSolver>
class make_block_solver
{
 public:
 
  typedef typename Precond::backend_type backend_type;
  typedef typename backend_type::value_type value_type;
  typedef typename backend_type::params backend_params;
  typedef typename backend_type::vector vector;
  typedef typename math::scalar_of<value_type>::type scalar_type;
 
  typedef typename PreconditionedSolver<Precond, IterativeSolver>::params params;
 
  template <class Matrix>
  make_block_solver(const Matrix& A,
                    const params& prm = params(),
                    const backend_params& bprm = backend_params())
  {
    S = std::make_shared<Solver>(adapter::block_matrix<value_type>(A), prm, bprm);
  }
 
  template <class Matrix, class Vec1, class Vec2>
  SolverResult operator()(const Matrix& A, const Vec1& rhs, Vec2&& x) const
  {
    auto F = backend::reinterpret_as_rhs<value_type>(rhs);
    auto X = backend::reinterpret_as_rhs<value_type>(x);
 
    return (*S)(A, F, X);
  }
 
  template <class Vec1, class Vec2>
  SolverResult operator()(const Vec1& rhs, Vec2&& x) const
  {
    auto F = backend::reinterpret_as_rhs<value_type>(rhs);
    auto X = backend::reinterpret_as_rhs<value_type>(x);
 
    return (*S)(F, X);
  }
 
  std::shared_ptr<typename Precond::matrix> system_matrix_ptr() const
  {
    return S->system_matrix_ptr();
  }
 
  typename Precond::matrix const& system_matrix() const
  {
    return S->system_matrix();
  }
 
  friend std::ostream& operator<<(std::ostream& os, const make_block_solver& p)
  {
    return os << *p.S << std::endl;
  }
 
  size_t bytes() const
  {
    return backend::bytes(*S);
  }
 
 private:
 
  typedef PreconditionedSolver<Precond, IterativeSolver> Solver;
  std::shared_ptr<Solver> S;
};
 
} // namespace Arcane::Alina
 
#endif