From owner-cvs-src@FreeBSD.ORG Tue Sep 30 13:45:16 2003 Return-Path: Delivered-To: cvs-src@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 6A8F016A4C1; Tue, 30 Sep 2003 13:45:16 -0700 (PDT) Received: from repoman.freebsd.org (repoman.freebsd.org [216.136.204.115]) by mx1.FreeBSD.org (Postfix) with ESMTP id 2BCE244029; Tue, 30 Sep 2003 13:45:15 -0700 (PDT) (envelope-from mux@FreeBSD.org) Received: from repoman.freebsd.org (localhost [127.0.0.1]) by repoman.freebsd.org (8.12.9/8.12.9) with ESMTP id h8UKjFXJ021973; Tue, 30 Sep 2003 13:45:15 -0700 (PDT) (envelope-from mux@repoman.freebsd.org) Received: (from mux@localhost) by repoman.freebsd.org (8.12.9/8.12.9/Submit) id h8UKjE9j021972; Tue, 30 Sep 2003 13:45:14 -0700 (PDT) (envelope-from mux) Message-Id: <200309302045.h8UKjE9j021972@repoman.freebsd.org> From: Maxime Henrion Date: Tue, 30 Sep 2003 13:45:14 -0700 (PDT) To: src-committers@FreeBSD.org, cvs-src@FreeBSD.org, cvs-all@FreeBSD.org X-FreeBSD-CVS-Branch: HEAD Subject: cvs commit: src/sys/sys cdefs.h X-BeenThere: cvs-src@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: CVS commit messages for the src tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 30 Sep 2003 20:45:16 -0000 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 Revision Changes Path 1.77 +36 -0 src/sys/sys/cdefs.h