anchor.diff:  
     ! set amg as the pcg preconditioner
     call HYPRE_ParCSRPCGSetPrecond(hypre_solver, 2, precond, ierr)
  +  print *, 'here', myid
   
     ! now we set the system up and do the actual solve!
     call HYPRE_ParCSRPCGSetup(hypre_solver, hypre_A, hypre_b, &
  
positive.code:   integer*8 :: precond
    integer   :: nentries, nvalues, stencil_indices(5)
    double precision :: values(nx * ny)
  
    integer :: MPI_COMM_WORLD
    integer :: num_procs
    integer :: ilower(0:num_procs-1,2), iupper(0:num_procs-1,2)
  
    ! Calculate the barotropic velocities
    call calc_baro_u(ub, unew, hnew, eta, freesurfFac, nx, ny, layers)
    call calc_baro_v(vb, vnew, hnew, eta, freesurfFac, nx, ny, layers)
  
negative.code:           dx, dy, wetmask, hfacW, hfacS, dt, &
            maxits, eps, rjac, freesurfFac, thickness_error, &
            g_vec, nx, ny, layers, n, &
            MPI_COMM_WORLD, myid, num_procs, ilower, iupper, &
            hypre_grid, hypre_b, ierr)
            ! , &
            ! MPI_COMM_WORLD, num_procs, ilower, iupper, &
  