From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <joerg@bec.de>
Received: from relay4-d.mail.gandi.net (relay4-d.mail.gandi.net
 [IPv6:2001:4b98:dc4:8::224])
 by sourceware.org (Postfix) with ESMTPS id CA7783858423
 for <gcc@gcc.gnu.org>; Fri, 21 Jan 2022 18:51:28 +0000 (GMT)
DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org CA7783858423
Authentication-Results: sourceware.org;
 dmarc=none (p=none dis=none) header.from=bec.de
Authentication-Results: sourceware.org; spf=none smtp.mailfrom=bec.de
Received: (Authenticated sender: joerg@bec.de)
 by mail.gandi.net (Postfix) with ESMTPSA id 09442E0003;
 Fri, 21 Jan 2022 18:51:25 +0000 (UTC)
Date: Fri, 21 Jan 2022 19:51:22 +0100
From: Joerg Sonnenberger <joerg@bec.de>
To: libc-coord@lists.openwall.com
Cc: GNU C Library <libc-alpha@sourceware.org>,
 Richard Biener via Gcc <gcc@gcc.gnu.org>
Subject: Re: [libc-coord] Add new ABIs '__strcmpeq', '__strncmpeq',
 '__wcscmpeq' and '__wcsncmpeq' to libc
Message-ID: <YesAqsfgEpBsEAOy@bec.de>
References: <CAFUsyfKOtCxcM84LAPwmh=h+Kkz7x-CvGvsBFUW-wY1Zjv00eg@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <CAFUsyfKOtCxcM84LAPwmh=h+Kkz7x-CvGvsBFUW-wY1Zjv00eg@mail.gmail.com>
X-Spam-Status: No, score=-0.9 required=5.0 tests=BAYES_00, KAM_DMARC_STATUS,
 KAM_LAZY_DOMAIN_SECURITY, SPF_HELO_NONE, SPF_NONE,
 TXREP autolearn=no autolearn_force=no version=3.4.4
X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on
 server2.sourceware.org
X-BeenThere: gcc@gcc.gnu.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Gcc mailing list <gcc.gcc.gnu.org>
List-Unsubscribe: <https://gcc.gnu.org/mailman/options/gcc>,
 <mailto:gcc-request@gcc.gnu.org?subject=unsubscribe>
List-Archive: <https://gcc.gnu.org/pipermail/gcc/>
List-Post: <mailto:gcc@gcc.gnu.org>
List-Help: <mailto:gcc-request@gcc.gnu.org?subject=help>
List-Subscribe: <https://gcc.gnu.org/mailman/listinfo/gcc>,
 <mailto:gcc-request@gcc.gnu.org?subject=subscribe>
X-List-Received-Date: Fri, 21 Jan 2022 18:51:30 -0000

On Thu, Jan 20, 2022 at 04:56:59PM -0600, Noah Goldstein wrote:
> The goal is that the new interfaces will be usable as an optimization
> by compilers if a program uses the return value of the non "eq"
> variant as a boolean.

So I'm curious, but can you demonstrate that it can be implemented
notacibly faster than regular strcmp? Unlike for memcmp, I don't see an
obvious way to save any operations.

Joerg