TRUSTTab_tools.cpp

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#include <TRUSTTab.h>
#include <TRUSTTab_tools.tpp>
#include <MD_Vector_seq.h>
#include <limits>
 
namespace
{
template <typename ExecSpace, typename _TYPE_>
void local_carre_norme_tab_kernel(const TRUSTTab<_TYPE_>& tableau, TRUSTArray<_TYPE_>& norme_colonne)
{
  const TRUSTVect<_TYPE_,int>& vect = tableau;
  const int lsize = vect.line_size(), vect_size_tot = vect.size_totale();
  assert(lsize == norme_colonne.size_array());
 
  int nblocs_left;
  Block_Iter<int> bloc_itr = ::determine_blocks(VECT_SEQUENTIAL_ITEMS, tableau.get_md_vector(), vect_size_tot, lsize, nblocs_left);
 
  for (int j = 0; j < lsize; j++) norme_colonne[j] = 0;
 
  auto tableau_view = tableau.template view_ro<2, ExecSpace>();
  auto norme_colonne_view = norme_colonne.template view_rw<1, ExecSpace>();
#ifdef TRUST_USE_GPU
  if (nblocs_left>3) ToDo_Kokkos("nblocs_left too high, optimize by rewriting as local_operations_vect_bis_generic_kernel");
#endif
  for (; nblocs_left; nblocs_left--)
    {
      const int begin_bloc = (*(bloc_itr++)), end_bloc = (*(bloc_itr++));
      if (begin_bloc<end_bloc) // very important: empty bloc at the end would erase norme_colonne
        {
          Kokkos::RangePolicy<ExecSpace> policy(begin_bloc, end_bloc);
 
          for (int j=0; j<lsize; j++) //Outer loop
            {
              if (statistics().get_use_gpu()) start_gpu_timer(__KERNEL_NAME__);
              Kokkos::parallel_reduce(policy,
                                      KOKKOS_LAMBDA(const int i, _TYPE_& local_sum)
              {
                const _TYPE_ x = tableau_view(i,j);
                local_sum += x*x;
              },
              //Reduce in a subview, enabled by specifying execspace in the reducer !
              Kokkos::Sum<_TYPE_, ExecSpace>(Kokkos::subview(norme_colonne_view,j)));
 
              bool kernelOnDevice = is_default_exec_space<ExecSpace>;
              if (statistics().get_use_gpu()) end_gpu_timer(__KERNEL_NAME__, kernelOnDevice);
            }
        }
    }
}
 
}
 
template <typename _TYPE_>
void local_carre_norme_tab(const TRUSTTab<_TYPE_>& tableau, TRUSTArray<_TYPE_>& norme_colonne)
{
  norme_colonne = 0.;
  bool kernelOnDevice = tableau.checkDataOnDevice();
 
  if (kernelOnDevice)
    local_carre_norme_tab_kernel<Kokkos::DefaultExecutionSpace, _TYPE_>(tableau, norme_colonne);
  else
    local_carre_norme_tab_kernel<Kokkos::DefaultHostExecutionSpace, _TYPE_>(tableau, norme_colonne);
}
 
namespace
{
template <typename ExecSpace, typename _TYPE_>
void local_max_abs_tab_kernel(const TRUSTTab<_TYPE_>& tableau, TRUSTArray<_TYPE_>& max_colonne)
{
  const TRUSTVect<_TYPE_,int>& vect = tableau;
  const int lsize = vect.line_size(), vect_size_tot = vect.size_totale();
  assert(lsize == max_colonne.size_array());
 
  int nblocs_left;
  Block_Iter<int> bloc_itr = ::determine_blocks(VECT_REAL_ITEMS, tableau.get_md_vector(), vect_size_tot, lsize, nblocs_left);
 
  for (int j = 0; j < lsize; j++) max_colonne[j] = 0;
  assert(lsize == max_colonne.size_array());
 
  auto tableau_view= tableau.template view_ro<2, ExecSpace>();
  auto max_colonne_view= max_colonne.template view_rw<1, ExecSpace>();
#ifdef TRUST_USE_GPU
  if (nblocs_left>3) ToDo_Kokkos("nblocs_left too high, optimize by rewriting as local_operations_vect_bis_generic_kernel");
#endif
  for (; nblocs_left; nblocs_left--)
    {
      const int begin_bloc = (*(bloc_itr++)), end_bloc = (*(bloc_itr++));
      if (begin_bloc<end_bloc) // very important: empty bloc at the end would erase max_colonne
        {
          Kokkos::RangePolicy<ExecSpace> policy(begin_bloc, end_bloc);
 
          for (int j=0; j<lsize; j++) //Outer loop
            {
              if (statistics().get_use_gpu()) start_gpu_timer(__KERNEL_NAME__);
              Kokkos::parallel_reduce(policy,
                                      KOKKOS_LAMBDA(const int i, _TYPE_& local_max)
              {
                const _TYPE_ x = Kokkos::fabs(tableau_view(i,j));
                local_max = Kokkos::fmax(local_max, x);
              },
              //Reduce in a subview, enabled by specifying execspace in the reducer !
              Kokkos::Max<_TYPE_, ExecSpace>(Kokkos::subview(max_colonne_view,j)));
 
              bool kernelOnDevice = is_default_exec_space<ExecSpace>;
              if (statistics().get_use_gpu()) end_gpu_timer(__KERNEL_NAME__, kernelOnDevice);
            }
        }
    }
}
 
}
 
template <typename _TYPE_>
void local_max_abs_tab(const TRUSTTab<_TYPE_>& tableau, TRUSTArray<_TYPE_>& max_colonne)
{
  max_colonne = std::numeric_limits<_TYPE_>::min();
  bool kernelOnDevice = tableau.checkDataOnDevice();
 
  if (kernelOnDevice)
    local_max_abs_tab_kernel<Kokkos::DefaultExecutionSpace, _TYPE_>(tableau, max_colonne);
  else
    local_max_abs_tab_kernel<Kokkos::DefaultHostExecutionSpace, _TYPE_>(tableau, max_colonne);
}
 
template void local_carre_norme_tab<double>(const TRUSTTab<double,int>& tableau, TRUSTArray<double,int>& norme_colonne);
template void local_carre_norme_tab<float>(const TRUSTTab<float,int>& tableau, TRUSTArray<float,int>& norme_colonne);
template void local_max_abs_tab<double>(const TRUSTTab<double,int>& tableau, TRUSTArray<double,int>& max_colonne);
template void local_max_abs_tab<float>(const TRUSTTab<float,int>& tableau, TRUSTArray<float,int>& max_colonne);