From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 27125 invoked by alias); 10 Mar 2004 11:25:21 -0000 Mailing-List: contact gcc-patches-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Archive: List-Post: List-Help: Sender: gcc-patches-owner@gcc.gnu.org Received: (qmail 27112 invoked from network); 10 Mar 2004 11:25:20 -0000 Received: from unknown (HELO mx1.redhat.com) (66.187.233.31) by sources.redhat.com with SMTP; 10 Mar 2004 11:25:20 -0000 Received: from int-mx1.corp.redhat.com (int-mx1.corp.redhat.com [172.16.52.254]) by mx1.redhat.com (8.12.10/8.12.10) with ESMTP id i2ABPK07021211; Wed, 10 Mar 2004 06:25:20 -0500 Received: from localhost (vpn50-8.rdu.redhat.com [172.16.50.8]) by int-mx1.corp.redhat.com (8.11.6/8.11.6) with ESMTP id i2ABPI802426; Wed, 10 Mar 2004 06:25:18 -0500 Received: from rsandifo by localhost with local (Exim 3.35 #1) id 1B11qE-00074G-00; Wed, 10 Mar 2004 11:25:38 +0000 To: Richard Henderson Cc: David Edelsohn , gcc-patches@gcc.gnu.org Subject: Re: Powerpc64 long double support References: <40491948.2010900@us.ibm.com> <20040306105033.GF2715@bubble.modra.org> <200403062313.i26NDipA015313@desire.geoffk.org> <20040307063708.GD18129@bubble.modra.org> <20040307073023.GA13420@redhat.com> <20040309050531.GG28377@bubble.modra.org> <20040309075945.GA25201@redhat.com> <20040309234922.GM28377@bubble.modra.org> <87k71tkpgz.fsf@redhat.com> <20040310110113.GS28377@bubble.modra.org> <20040310111351.GT28377@bubble.modra.org> From: Richard Sandiford Date: Wed, 10 Mar 2004 11:25:00 -0000 In-Reply-To: <20040310111351.GT28377@bubble.modra.org> (Alan Modra's message of "Wed, 10 Mar 2004 21:43:51 +1030") Message-ID: <877jxtkkp9.fsf@redhat.com> User-Agent: Gnus/5.1006 (Gnus v5.10.6) Emacs/21.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-SW-Source: 2004-03.o/txt/msg00847.txt Alan Modra writes: > On Wed, Mar 10, 2004 at 09:31:13PM +1030, Alan Modra wrote: >> On Wed, Mar 10, 2004 at 09:42:36AM +0000, Richard Sandiford wrote: >> > when compiled with MIPSpro cc. >> >> Does MIPSpro correctly convert a long double -0.0 to double -0.0? Does >> mips gcc? > > The reason for -0.0 in the low double goes like this: > > Conversion from long double to double is done by simply adding the > two component doubles. That means long double -0.0 must be > (-0.0 + -0.0), or you need to add code to handle -0.0 on every > conversion. Not sure: are you saying that's what the spec says you should do, or that is it just what a particular implementation does? As per my previous message, IRIX uses +0.0 for the low double and it still gets the conversion right. I assume it must be using something other than simple addition. My only concern (in case it wasn't obvious ;) is that you don't change the behaviour for IRIX. I'm certainly not trying to say the change is wrong for powerpc... Richard From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 27125 invoked by alias); 10 Mar 2004 11:25:21 -0000 Mailing-List: contact gcc-patches-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Archive: List-Post: List-Help: Sender: gcc-patches-owner@gcc.gnu.org Received: (qmail 27112 invoked from network); 10 Mar 2004 11:25:20 -0000 Received: from unknown (HELO mx1.redhat.com) (66.187.233.31) by sources.redhat.com with SMTP; 10 Mar 2004 11:25:20 -0000 Received: from int-mx1.corp.redhat.com (int-mx1.corp.redhat.com [172.16.52.254]) by mx1.redhat.com (8.12.10/8.12.10) with ESMTP id i2ABPK07021211; Wed, 10 Mar 2004 06:25:20 -0500 Received: from localhost (vpn50-8.rdu.redhat.com [172.16.50.8]) by int-mx1.corp.redhat.com (8.11.6/8.11.6) with ESMTP id i2ABPI802426; Wed, 10 Mar 2004 06:25:18 -0500 Received: from rsandifo by localhost with local (Exim 3.35 #1) id 1B11qE-00074G-00; Wed, 10 Mar 2004 11:25:38 +0000 To: Richard Henderson Cc: David Edelsohn , gcc-patches@gcc.gnu.org Subject: Re: Powerpc64 long double support References: <40491948.2010900@us.ibm.com> <20040306105033.GF2715@bubble.modra.org> <200403062313.i26NDipA015313@desire.geoffk.org> <20040307063708.GD18129@bubble.modra.org> <20040307073023.GA13420@redhat.com> <20040309050531.GG28377@bubble.modra.org> <20040309075945.GA25201@redhat.com> <20040309234922.GM28377@bubble.modra.org> <87k71tkpgz.fsf@redhat.com> <20040310110113.GS28377@bubble.modra.org> <20040310111351.GT28377@bubble.modra.org> From: Richard Sandiford Date: Fri, 19 Mar 2004 08:14:00 -0000 In-Reply-To: <20040310111351.GT28377@bubble.modra.org> (Alan Modra's message of "Wed, 10 Mar 2004 21:43:51 +1030") Message-ID: <877jxtkkp9.fsf@redhat.com> User-Agent: Gnus/5.1006 (Gnus v5.10.6) Emacs/21.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-SW-Source: 2004-03/txt/msg00847.txt.bz2 Message-ID: <20040319081400.lCxQN5gwrJg0W2WNgYwyO4GkMDr0R1FjnxXCTFBaz5Q@z> Alan Modra writes: > On Wed, Mar 10, 2004 at 09:31:13PM +1030, Alan Modra wrote: >> On Wed, Mar 10, 2004 at 09:42:36AM +0000, Richard Sandiford wrote: >> > when compiled with MIPSpro cc. >> >> Does MIPSpro correctly convert a long double -0.0 to double -0.0? Does >> mips gcc? > > The reason for -0.0 in the low double goes like this: > > Conversion from long double to double is done by simply adding the > two component doubles. That means long double -0.0 must be > (-0.0 + -0.0), or you need to add code to handle -0.0 on every > conversion. Not sure: are you saying that's what the spec says you should do, or that is it just what a particular implementation does? As per my previous message, IRIX uses +0.0 for the low double and it still gets the conversion right. I assume it must be using something other than simple addition. My only concern (in case it wasn't obvious ;) is that you don't change the behaviour for IRIX. I'm certainly not trying to say the change is wrong for powerpc... Richard