gistfile1.f90

    ! Save core/non-core/l1/l2 distinction in mesh node_classes
    if (have_halos) then
       tmp = entity_counts(0)   ! number of vertices in topology mesh (-1?)
       ! Number of nodes in mesh?
       if ( dofs_per(mesh_dim(mesh)) > 0 ) then
          tmp = ((tmp + 1) * dofs_per(mesh_dim(mesh))) - 1
       end if
       ! Count core nodes (primary sort key -2)
       mesh%node_classes(CORE_ENTITY) = count(entity_sort_list(1:tmp, 0) == -2)
       ! Count non-core nodes (primary sort key -1)
       mesh%node_classes(NON_CORE_ENTITY) = count(entity_sort_list(1:tmp, 0) == -1)
       ! L1 halo (primary sort key \in [0, COMM_SIZE]) 
       mesh%node_classes(EXEC_HALO_ENTITY) = count(entity_sort_list(1:tmp, 0) >= 0 .and. entity_sort_list(1:tmp, 0) <= getnprocs())
       ! L2 halo (primary sort key \in [COMM_SIZE + 1, \infty))
       mesh%node_classes(NON_EXEC_HALO_ENTITY) = count(entity_sort_list(1:tmp, 0) > getnprocs())
    end if