[Bug fortran/85531] Implement some loop fusion in the Fortran front end

[rguenther at suse dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85531

--- Comment #5 from rguenther at suse dot de <rguenther at suse dot de> ---
On April 26, 2018 6:09:40 PM GMT+02:00, "tkoenig at gcc dot gnu.org"
<gcc-bugzilla@gcc.gnu.org> wrote:
>https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85531
>
>--- Comment #4 from Thomas Koenig <tkoenig at gcc dot gnu.org> ---
>What is the best strategy on this?
>
>I assume the Fortran front end could do a dependency analysis,
>the existing code could be extended for this.
>
>We could then either do the scalarization in the front end, or
>annotate the generated loops in some way to indicate that it
>is OK to merge them.
>
>What would be preferred?

Well. I think we need sth in the middle end. In the end the question will be
whether that's good enough or whether the frontend can do better in some cases.
We _do_ have issues with the frontend lowering everything to 1-dimensional
accesses.