From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 40216 invoked by alias); 23 Dec 2017 22:08:25 -0000 Mailing-List: contact gcc-patches-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-patches-owner@gcc.gnu.org Received: (qmail 40189 invoked by uid 89); 23 Dec 2017 22:08:24 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-1.7 required=5.0 tests=AWL,BAYES_00,KAM_NUMSUBJECT,T_RP_MATCHES_RCVD autolearn=no version=3.3.2 spammy= X-HELO: gate.crashing.org Received: from gate.crashing.org (HELO gate.crashing.org) (63.228.1.57) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Sat, 23 Dec 2017 22:08:23 +0000 Received: from gate.crashing.org (localhost.localdomain [127.0.0.1]) by gate.crashing.org (8.14.1/8.14.1) with ESMTP id vBNM8ImU007379; Sat, 23 Dec 2017 16:08:19 -0600 Received: (from segher@localhost) by gate.crashing.org (8.14.1/8.14.1/Submit) id vBNM8IvI007378; Sat, 23 Dec 2017 16:08:18 -0600 Date: Sat, 23 Dec 2017 22:08:00 -0000 From: Segher Boessenkool To: David Esparza Cc: gcc-patches@gcc.gnu.org Subject: Re: [PATCH] Change PRED_LOOP_EXIT from 85 to 92 Message-ID: <20171223220816.GG10515@gate.crashing.org> References: <20171222225347.18748-1-david.esparza.borquez@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20171222225347.18748-1-david.esparza.borquez@intel.com> User-Agent: Mutt/1.4.2.3i X-IsSubscribed: yes X-SW-Source: 2017-12/txt/msg01503.txt.bz2 On Fri, Dec 22, 2017 at 04:53:47PM -0600, David Esparza wrote: > With a value of 85 GCC has a CPU performance degradation of 11%, > reverting PRED_LOOP_EXIT to 92 this degradation disappear. > Those values where measured by running c-ray ray-tracer that is a > floating point benchmark that runs out of L1 cache. Why is this single benchmark more important than everything else? https://patchwork.ozlabs.org/patch/637073/ Segher