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From: "tnfchris at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/113134] gcc does not version loops with early break
 conditions that don't have side-effects
Date: Thu, 28 Dec 2023 05:08:41 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D113134

--- Comment #16 from Tamar Christina <tnfchris at gcc dot gnu.org> ---
>=20
> I wonder whether ARM SVE can also use this approach VEC_EXTRACT with inde=
x =3D
> 0.

Perhaps, I'll look into it thanks. though this is ofcourse only applicable =
when
the mask comes from whilelo.

In the future when we get to loops such as:

for (int i =3D ..;;)
{
  if (a)
    {
      ....
      if (b)
        return i;
    }
}

the reduction would come from the first active element of the mask created =
by
the condition a and not the whilelo.=