From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-bugzilla@gcc.gnu.org>
Received: by sourceware.org (Postfix, from userid 48)
	id 950A83935DF9; Wed,  5 Jun 2024 13:21:36 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 950A83935DF9
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org;
	s=default; t=1717593696;
	bh=yXeU1uYblPEY2hV9UTlUbdw175VV9xwyf3i8vGZJ+ts=;
	h=From:To:Subject:Date:In-Reply-To:References:From;
	b=L+bVwLqyeUzlRzbIaADirDGfvQ+oqR++6DtvuzAfnOrrWJlE3jsn3spa2DzPqMtVw
	 0WVWwKLJ0l5nIr27RT8+nzgTfhltls42iDmrbaugwCZySzSLsOYZUZm/hs0nPdTHMj
	 oou0dr6mxHnZCgWjW26CRvbIchztx4s8jKRDViGM=
From: "cvs-commit at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/115342] [14/15 Regression] AArch64: Function
 multiversioning initialization incorrect
Date: Wed, 05 Jun 2024 13:21:36 +0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: target
X-Bugzilla-Version: 14.0
X-Bugzilla-Keywords: 
X-Bugzilla-Severity: normal
X-Bugzilla-Who: cvs-commit at gcc dot gnu.org
X-Bugzilla-Status: UNCONFIRMED
X-Bugzilla-Resolution: 
X-Bugzilla-Priority: P3
X-Bugzilla-Assigned-To: wilco at gcc dot gnu.org
X-Bugzilla-Target-Milestone: 14.2
X-Bugzilla-Flags: 
X-Bugzilla-Changed-Fields: 
Message-ID: <bug-115342-4-ciYOgKBBwV@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-115342-4@http.gcc.gnu.org/bugzilla/>
References: <bug-115342-4@http.gcc.gnu.org/bugzilla/>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/
Auto-Submitted: auto-generated
MIME-Version: 1.0
List-Id: <gcc-bugs.sourceware.org>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D115342

--- Comment #1 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Wilco Dijkstra <wilco@gcc.gnu.org>:

https://gcc.gnu.org/g:d7cbcfe7c33645eaf95f175f19884d443817857b

commit r15-1036-gd7cbcfe7c33645eaf95f175f19884d443817857b
Author: Wilco Dijkstra <wilco.dijkstra@arm.com>
Date:   Wed Jun 5 14:04:33 2024 +0100

    AArch64: Fix cpu features initialization [PR115342]

    The CPU features initialization code uses CPUID registers (rather than
    HWCAP).  The equality comparisons it uses are incorrect: for example
FEAT_SVE
    is not set if SVE2 is available.  Using HWCAPs for these is both simpler
and
    correct.  The initialization must also be done atomically to avoid mult=
iple
    threads causing corruption due to non-atomic RMW accesses to the global.

    libgcc:
            PR target/115342
            * config/aarch64/cpuinfo.c (__init_cpu_features_constructor):
            Use HWCAP where possible.  Use atomic write for initialization.
            Fix FEAT_PREDRES comparison.
            (__init_cpu_features_resolver): Use atomic load for correct
            initialization.
            (__init_cpu_features): Likewise.=