From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id 88A0C384DB4B; Thu, 15 Feb 2024 13:10:31 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 88A0C384DB4B DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1708002631; bh=U1iv8YWTs9dcM08O4ACcgQlq8MDaFnnr23pv1HSSzII=; h=From:To:Subject:Date:In-Reply-To:References:From; b=S3+j4QwdC8th79LvDzahjdnTpvRrzjBt/9SG71nTYokdr5HsnkWQy/u9ceFbqgDoD x/N+hIcdtWTrdh3qT7CZtnKEzAScHU93MeRa6VfomWl/Ek6g89ey/aan8Ps7Gwwxnc dGbBdvbPCMKWAJpsNOizjMvT+YqLbqcDzvrx6cSs= From: "redi at gcc dot gnu.org" To: gcc-bugs@gcc.gnu.org Subject: [Bug libstdc++/113807] [performance] bitset::set not using memset opportunity Date: Thu, 15 Feb 2024 13:10:30 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: libstdc++ X-Bugzilla-Version: 14.0 X-Bugzilla-Keywords: missed-optimization X-Bugzilla-Severity: normal X-Bugzilla-Who: redi at gcc dot gnu.org X-Bugzilla-Status: NEW X-Bugzilla-Resolution: X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org X-Bugzilla-Target-Milestone: 14.0 X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: 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: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D113807 --- Comment #7 from Jonathan Wakely --- Hmm, yes, the code for bitset::set() is actually similar to what we get = for foo() in comment 5. The new version with memset does produce different (vectorized?) code though. For operator=3D=3D the current code is quite branchy, and looks better with= memcmp to me (but I don't really know what I'm talking about).=