From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 18122 invoked by alias); 12 Feb 2015 12:39:30 -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 18070 invoked by uid 89); 12 Feb 2015 12:39:29 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.3 required=5.0 tests=AWL,BAYES_00,RCVD_IN_DNSWL_LOW,SPF_PASS autolearn=ham version=3.3.2 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; Thu, 12 Feb 2015 12:39:27 +0000 Received: from nat-ies.mentorg.com ([192.94.31.2] helo=SVR-IES-FEM-01.mgc.mentorg.com) by relay1.mentorg.com with esmtp id 1YLt3E-0003rs-4w from joseph_myers@mentor.com ; Thu, 12 Feb 2015 04:39:24 -0800 Received: from digraph.polyomino.org.uk (137.202.0.76) by SVR-IES-FEM-01.mgc.mentorg.com (137.202.0.104) with Microsoft SMTP Server id 14.3.224.2; Thu, 12 Feb 2015 12:39:22 +0000 Received: from jsm28 (helo=localhost) by digraph.polyomino.org.uk with local-esmtp (Exim 4.82) (envelope-from ) id 1YLt3B-000546-Dk; Thu, 12 Feb 2015 12:39:21 +0000 Date: Thu, 12 Feb 2015 12:39:00 -0000 From: Joseph Myers To: James Bowman CC: "gcc-patches@gcc.gnu.org" Subject: RE: [PATCH, FT32] initial support In-Reply-To: Message-ID: References: , , User-Agent: Alpine 2.10 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" X-SW-Source: 2015-02/txt/msg00759.txt.bz2 On Wed, 11 Feb 2015, James Bowman wrote: > > > +@table @gcctabopt > > > + > > > +@item -mspace > > > +@opindex mspace > > > +Enable code-size optimizations. > > > +Some of these optimizations incur a minor performance penalty. > > > > We already have -Os, so why is an architecture-specific option for this > > needed? > > Code compiled with -mspace is somewhat slower than code without. > So we typically build *all* code with -Os, with everything > non-critical also compiled -mspace. The typical way of doing that would be to compile the critical code with -O2, everything else with -Os. It's expected -Os may produce slower code than -O2. -- Joseph S. Myers joseph@codesourcery.com