ArrayRangeToLoopTrans over cautious with index expressions

[arporter]

Given the following code:

module my_mod
  use some_mod
  implicit none

contains

  subroutine my_sub()
    integer :: iihom, jl
    real, dimension(10,10,10) :: ptab
    SELECT CASE ( pmpp%nbondi )      ! Read Dirichlet lateral conditions
      CASE ( -1, 0, 1 )                ! all exept 2 (i.e. close case)
         iihom = pmpp%nlci-pmpp%nreci
         DO jl = 1, jpreci
            pmpp%flbc%t3ew(:,jl,:,1) = ptab(jpreci+jl,:,:)
            pmpp%flbc%t3we(:,jl,:,1) = ptab(iihom +jl,:,:)
         END DO
      END SELECT
    end subroutine my_sub

  end module my_mod

NemoAllArrayRange2LoopTrans will successfully convert the last assignment into a loop but refuses to do the penultimate one because it doesn't know anything about the type of jpreci. In this case we can determine that it must be a scalar because otherwise the shape of the RHS would not conform to the shape of the LHS. I'm not sure how easy it would be to put this logic into the transformation but it would be nice to have it as it's quite hard to track down why PSyclone refused to do the transformation.