1: !
  2: !
  3: !    Fortran kernel for sparse matrix-vector product in the AIJ/CRL format
  4: !
  5: #include <petsc/finclude/petscsys.h>
  6: !
  7: pure subroutine FortranMultCRL(m,rmax,x,y,icols,acols)
  8:   use, intrinsic :: ISO_C_binding
  9:   implicit none (type, external)
 10:   PetscInt, intent(in) :: m,rmax,icols(m,rmax)
 11:   PetscScalar, intent(in) :: x(0:m-1), acols(m,rmax)
 12:   PetscScalar, intent(out) :: y(m)

 14:   PetscInt :: i

 16:   y(1:m) = acols(1:m,1)*x(icols(1:m,1))
 17:   do i=2,rmax
 18:     y(1:m) = y(1:m) + acols(1:m,i)*x(icols(1:m,i))
 19:   end do
 20: end subroutine FortranMultCRL