Solv_Externe.cpp

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#include <Solv_Externe.h>
#include <Matrice_Base.h>
#include <Matrice_Morse_Sym.h>
#include <Matrice_Bloc_Sym.h>
#include <Device.h>
 
Implemente_base_sans_constructeur_ni_destructeur(Solv_Externe,"Solv_Externe",SolveurSys_base);
 
Sortie& Solv_Externe::printOn(Sortie& s) const
{
  //s << chaine_lue_;
  return s;
}
 
// readOn
Entree& Solv_Externe::readOn(Entree& is)
{
  //create_solver(is);
  return is;
}
 
void Solv_Externe::MorseSymToMorse(const Matrice_Morse_Sym& MS, Matrice_Morse& M)
{
  M = MS;
  Matrice_Morse mattmp(MS);
  M.transpose(mattmp);
  int ordre = M.ordre();
  for (int i=0; i<ordre; i++)
    if (M.nb_vois(i))
      M(i, i) = 0.;
  M = mattmp + M;
}
 
void Solv_Externe::construit_matrice_morse_intermediaire(const Matrice_Base& la_matrice, Matrice_Morse& matrice_morse_intermediaire)
{
  if (sub_type(Matrice_Morse_Sym, la_matrice))
    {
      // Example: pressure matrix in VEFPreP1B
      const Matrice_Morse_Sym& matrice_morse_sym = ref_cast(Matrice_Morse_Sym, la_matrice);
      assert(matrice_morse_sym.get_est_definie());
      MorseSymToMorse(matrice_morse_sym, matrice_morse_intermediaire);
    }
  else if (sub_type(Matrice_Bloc_Sym, la_matrice))
    {
      // Example: pressure matrix in VEF P0+P1+Pa
      const Matrice_Bloc_Sym& matrice = ref_cast(Matrice_Bloc_Sym, la_matrice);
      // Convert the Matrice_Bloc_Sym to Matrice_Morse_Sym format
      Matrice_Morse_Sym matrice_morse_sym;
      matrice.BlocSymToMatMorseSym(matrice_morse_sym);
      MorseSymToMorse(matrice_morse_sym, matrice_morse_intermediaire);
      matrice_morse_sym.dimensionner(0, 0); // Destroy the Morse sym matrix now that it is no longer needed
    }
  else if (sub_type(Matrice_Morse, la_matrice))
    {
      // Example: implicit matrix
      matrice_symetrique_ = false;
    }
  else if (sub_type(Matrice_Bloc, la_matrice))
    {
      // Example: pressure matrix in VDF
      const Matrice_Bloc& matrice_bloc = ref_cast(Matrice_Bloc, la_matrice);
      if (!sub_type(Matrice_Morse_Sym, matrice_bloc.get_bloc(0, 0).valeur()))
        matrice_symetrique_ = false;
      else
        {
          // For a direct solver: fix the matrix if it is not defined (in incompressible VDF, nothing was done before...)
          Matrice_Morse_Sym& mat00 = ref_cast_non_const(Matrice_Morse_Sym, matrice_bloc.get_bloc(0, 0).valeur());
          if (solveur_direct() && mat00.get_est_definie() == 0 && Process::je_suis_maitre())
            mat00(0, 0) *= 2;
        }
      matrice_bloc.BlocToMatMorse(matrice_morse_intermediaire);
    }
  else
    {
      Cerr << "Error, we do not know yet treat a matrix of type " << la_matrice.que_suis_je() << finl;
      exit();
    }
}
 
const ArrOfInt& Solv_Externe::indice_coeff_to_keep(const Matrice_Morse& matrice_morse)
{
  if (!indice_coeff_to_keep_.size_array())
    {
      // Build indice_coeff_to_keep_
      const auto& tab1 = matrice_morse.get_tab1();
      const int n = tab1.size_array() - 1;
      auto nnz(tab1[0]);
      nnz = 0;
      for (int i = 0; i < n; i++)
        {
          if (items_to_keep_[i])
            nnz += tab1[i + 1] - tab1[i];
        }
      indice_coeff_to_keep_.resize((int)nnz);
      nnz = 0;
      for (int i = 0; i < n; i++)
        {
          if (items_to_keep_[i])
            {
              const auto k0 = tab1[i] - 1;
              const auto k1 = tab1[i + 1] - 1;
              for (auto k = k0; k < k1; k++)
                {
                  indice_coeff_to_keep_[(int)nnz] = (int)k;
                  nnz++;
                }
            }
        }
    }
  return indice_coeff_to_keep_;
}
 
void Solv_Externe::Create_lhs_rhs_onDevice()
{
  lhs_.resize(nb_rows_);
  rhs_.resize(nb_rows_);
}
 
template<typename ExecSpace>
void Solv_Externe::Update_lhs_rhs(const DoubleVect& tab_b, DoubleVect& tab_x)
{
  const unsigned int size = tab_b.size_array();
  auto x = tab_x.template view_ro<1, ExecSpace>();
  auto b = tab_b.template view_ro<1, ExecSpace>();
  auto index = static_cast<const ArrOfInt&>(index_).template view_ro<1, ExecSpace>();
  auto lhs = lhs_.template view_wo<1, ExecSpace>();
  auto rhs = rhs_.template view_wo<1, ExecSpace>();
  Kokkos::RangePolicy<ExecSpace> policy(0, size);
  Kokkos::parallel_for(start_gpu_timer(__KERNEL_NAME__), policy, KOKKOS_LAMBDA(
                         const int i)
  {
    int ind = index[i];
    if (ind != -1)
      {
        lhs[ind] = x[i];
        rhs[ind] = b[i];
      }
  });
  static constexpr bool kernelOnDevice = !std::is_same<ExecSpace, Kokkos::DefaultHostExecutionSpace>::value;
  end_gpu_timer(__KERNEL_NAME__, kernelOnDevice);
}
 
template<typename ExecSpace>
void Solv_Externe::Update_solution(DoubleVect& tab_x)
{
  const unsigned int size = tab_x.size_array();
  auto index = static_cast<const ArrOfInt&>(index_).template view_ro<1, ExecSpace>();
  auto lhs = lhs_.template view_ro<1, ExecSpace>();
  auto x = tab_x.template view_wo<1, ExecSpace>();
  Kokkos::RangePolicy<ExecSpace> policy(0, size);
  Kokkos::parallel_for(start_gpu_timer(__KERNEL_NAME__), policy, KOKKOS_LAMBDA(
                         const int i)
  {
    int ind = index[i];
    if (ind != -1)
      x[i] = lhs[ind];
  });
  static constexpr bool kernelOnDevice = !std::is_same<ExecSpace, Kokkos::DefaultHostExecutionSpace>::value;
  end_gpu_timer(__KERNEL_NAME__, kernelOnDevice);
}
 
#ifdef TRUST_USE_GPU
template void Solv_Externe::Update_lhs_rhs<Kokkos::DefaultExecutionSpace>(const DoubleVect&, DoubleVect&);
template void Solv_Externe::Update_solution<Kokkos::DefaultExecutionSpace>(DoubleVect&);
#endif
template void Solv_Externe::Update_lhs_rhs<Kokkos::DefaultHostExecutionSpace>(const DoubleVect&, DoubleVect&);
template void Solv_Externe::Update_solution<Kokkos::DefaultHostExecutionSpace>(DoubleVect&);