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From: "crazylht at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/111972] [14 regression] missed vectorzation
 for bool a = j != 1; j = (long int)a;
Date: Fri, 27 Oct 2023 05:17:56 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D111972

--- Comment #7 from Hongtao.liu <crazylht at gmail dot com> ---
(In reply to Andrew Pinski from comment #3)
> First off does this even make sense to vectorize but rather do some kind =
of
> scalar reduction with respect to j =3D j^1 here  .  Filed PR 112104 for t=
hat.
>=20
> Basically vectorizing this loop is a waste compared to that.

Yes, it's always zero, it would be nice if the middle end can optimize the
whole loop off. So for this PR, it's more related to the misoptimization of=
 the
redundant loop(better finalize the induction variable with a simple
assignment), not vectorization.=