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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/113441] [14 Regression] Fail to fold the last
 element with multiple loop
Date: Tue, 23 Jan 2024 10:29:01 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D113441

--- Comment #15 from rguenther at suse dot de <rguenther at suse dot de> ---
On Tue, 23 Jan 2024, juzhe.zhong at rivai dot ai wrote:

> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D113441
>=20
> --- Comment #14 from JuzheZhong <juzhe.zhong at rivai dot ai> ---
> I just tried again both GCC-13.2 and GCC-14 with -fno-vect-cost-model.
>=20
> https://godbolt.org/z/enEG3qf5K
>=20
> GCC-14 requires scalar epilogue loop, whereas GCC-13.2 doesn't.
>=20
> I believe it's not cost model issue.

As said, please try to bisect to the point where we started to require
the epilogue.=