From owner-cvs-all@FreeBSD.ORG Tue Sep 30 23:16:44 2003 Return-Path: Delivered-To: cvs-all@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id C808A16A4B3; Tue, 30 Sep 2003 23:16:44 -0700 (PDT) Received: from VARK.homeunix.com (adsl-68-122-2-142.dsl.pltn13.pacbell.net [68.122.2.142]) by mx1.FreeBSD.org (Postfix) with ESMTP id C634943FD7; Tue, 30 Sep 2003 23:16:42 -0700 (PDT) (envelope-from das@FreeBSD.ORG) Received: from VARK.homeunix.com (localhost [127.0.0.1]) by VARK.homeunix.com (8.12.9/8.12.9) with ESMTP id h916GdtU019114; Tue, 30 Sep 2003 23:16:39 -0700 (PDT) (envelope-from das@FreeBSD.ORG) Received: (from das@localhost) by VARK.homeunix.com (8.12.9/8.12.9/Submit) id h916GdEZ019113; Tue, 30 Sep 2003 23:16:39 -0700 (PDT) (envelope-from das@FreeBSD.ORG) Date: Tue, 30 Sep 2003 23:16:39 -0700 From: David Schultz To: Maxime Henrion Message-ID: <20031001061639.GA19012@VARK.homeunix.com> Mail-Followup-To: Maxime Henrion , src-committers@FreeBSD.ORG, cvs-src@FreeBSD.ORG, cvs-all@FreeBSD.ORG References: <200309302045.h8UKjE9j021972@repoman.freebsd.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200309302045.h8UKjE9j021972@repoman.freebsd.org> cc: cvs-src@FreeBSD.ORG cc: src-committers@FreeBSD.ORG cc: cvs-all@FreeBSD.ORG Subject: Re: cvs commit: src/sys/sys cdefs.h X-BeenThere: cvs-all@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: CVS commit messages for the entire tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 01 Oct 2003 06:16:44 -0000 On Tue, Sep 30, 2003, Maxime Henrion wrote: > mux 2003/09/30 13:45:14 PDT > > FreeBSD src repository > > Modified files: > sys/sys cdefs.h > Log: > Introduce new __predict_false(exp) and __predict_true(exp) keywords. > Their purpose is to give explicit hints to the compiler to judge > the likelyhood of a test to succeed or fail. Not all architectures > have support for such optimizations, but for those who do, it can > give a nice performance improvement in hot loops. > > Obviously, this should be used very rarely in very specific code. > > Reviewed by: peter > Obtained from: OpenBSD Cool, I'm glad we finally have these. (FWIW, I believe the macros originated with NetBSD.) Hopefully they will be used with reservation.