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From: "tnfchris at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/114403] [14 regression] LLVM miscompiled with
 -O3 -march=znver2 -fno-vect-cost-model since r14-6822-g01f4251b8775c8
Date: Fri, 12 Apr 2024 10:40:24 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D114403

--- Comment #26 from Tamar Christina <tnfchris at gcc dot gnu.org> ---
(In reply to Richard Biener from comment #25)
> That means, when the loop takes the early exit we _must_ take that during
> the vector iterations.  Peeling for gaps means if we would take the early
> exit during one of the gap peeled iterations this is a conflicting
> requirement.
> Now - the current analysis guarantees that the early exit conditions can
> be safely evaluated even for the gap iterations, but not the following
> code when the early exit is _not_ taken.
>=20
> So peeling for gaps and early exit vect are not compatible?

I don't see why not, as my email explains for the early exits we always go
to the scalar loop, which already adheres to the condition of peeling for
gaps.

I just think that peeling for gaps should not force it to exit from the main
exit.=