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From: "rguenther at suse dot de" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/114635] OpenMP reductions fail dependency
 analysis
Date: Mon, 15 Apr 2024 08:08:14 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D114635

--- Comment #15 from rguenther at suse dot de <rguenther at suse dot de> ---
On Mon, 15 Apr 2024, jakub at gcc dot gnu.org wrote:

> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D114635
>=20
> --- Comment #13 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
> (In reply to kugan from comment #12)
> > > Why?
> > > Then it just is INT_MAX value, which is a magic value that says that =
it is
> > > infinity.
> > > No need to say it is a poly_int infinity.
> >=20
> > For this test case, omp_max_vf gets [16, 16] from the backend. This then
> > becomes 16. If we keep it as poly_int, it would pass maybe_lt (max_vf,
> > min_vf)) after applying safelen?
>=20
> No.  You should just special case loop->safelen =3D=3D INT_MAX to mean in=
finity in
> the comparisons where it currently doesn't work as infinity.

But then an actual safelen(INT_MAX) would need to be adjusted.

Maybe using a poly-int safelen internally is cleaner.=