From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 89592 invoked by alias); 13 Sep 2016 16:08:42 -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 89523 invoked by uid 89); 13 Sep 2016 16:08:41 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-1.9 required=5.0 tests=AWL,BAYES_00,RCVD_IN_DNSWL_NONE,SPF_PASS,URIBL_RED autolearn=ham version=3.3.2 spammy= X-HELO: relay1.mentorg.com Received: from relay1.mentorg.com (HELO relay1.mentorg.com) (192.94.38.131) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Tue, 13 Sep 2016 16:08:31 +0000 Received: from nat-ies.mentorg.com ([192.94.31.2] helo=svr-ies-mbx-01.mgc.mentorg.com) by relay1.mentorg.com with esmtp id 1bjqG4-0005QF-LQ from joseph_myers@mentor.com ; Tue, 13 Sep 2016 09:08:28 -0700 Received: from digraph.polyomino.org.uk (137.202.0.87) by svr-ies-mbx-01.mgc.mentorg.com (139.181.222.1) with Microsoft SMTP Server (TLS) id 15.0.1210.3; Tue, 13 Sep 2016 17:08:25 +0100 Received: from jsm28 (helo=localhost) by digraph.polyomino.org.uk with local-esmtp (Exim 4.86_2) (envelope-from ) id 1bjqFx-0003DJ-67; Tue, 13 Sep 2016 16:08:21 +0000 Date: Tue, 13 Sep 2016 16:10:00 -0000 From: Joseph Myers To: Wilco Dijkstra CC: Jakub Jelinek , Tamar Christina , GCC Patches , "rguenther@suse.de" , Jeff Law , nd Subject: Re: [PATCH] Optimise the fpclassify builtin to perform integer operations when possible In-Reply-To: Message-ID: References: User-Agent: Alpine 2.20 (DEB 67 2015-01-07) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" X-ClientProxiedBy: svr-ies-mbx-01.mgc.mentorg.com (139.181.222.1) To svr-ies-mbx-01.mgc.mentorg.com (139.181.222.1) X-SW-Source: 2016-09/txt/msg00749.txt.bz2 On Tue, 13 Sep 2016, Wilco Dijkstra wrote: > I would suggest someone with access to a machine with slow FP moves (POWER?) > to benchmark this using the fpclassify test (glibc/benchtests/bench-math-inlines.c) > so we know for sure. And if for some operations on some architectures the floating-point version is faster, that just means we need a hook to choose between them (in the default -fno-signaling-nans case, since -fsignaling-nans should always use the integer version). -- Joseph S. Myers joseph@codesourcery.com