From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 28135 invoked by alias); 26 Jul 2004 21:12:16 -0000 Mailing-List: contact gdb-patches-help@sources.redhat.com; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sources.redhat.com Received: (qmail 28121 invoked from network); 26 Jul 2004 21:12:15 -0000 Received: from unknown (HELO mx1.redhat.com) (66.187.233.31) by sourceware.org with SMTP; 26 Jul 2004 21:12:15 -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 i6QLCEe3002167; Mon, 26 Jul 2004 17:12:15 -0400 Received: from localhost.redhat.com (porkchop.devel.redhat.com [172.16.58.2]) by int-mx1.corp.redhat.com (8.11.6/8.11.6) with ESMTP id i6QLCDa32618; Mon, 26 Jul 2004 17:12:14 -0400 Received: from gnu.org (localhost [127.0.0.1]) by localhost.redhat.com (Postfix) with ESMTP id 444872B9D; Mon, 26 Jul 2004 17:12:10 -0400 (EDT) Message-ID: <410573AA.4090805@gnu.org> Date: Mon, 26 Jul 2004 21:12:00 -0000 From: Andrew Cagney User-Agent: Mozilla/5.0 (X11; U; NetBSD macppc; en-GB; rv:1.4.1) Gecko/20040217 MIME-Version: 1.0 To: DJ Delorie Cc: zack@codesourcery.com, binutils@sources.redhat.com, gdb-patches@sources.redhat.com Subject: Re: [patch/rfc] Add host's floatformat References: <40939DD4.3000706@gnu.org> <4093DC36.9040304@gnu.org> <200405020312.i423CSlH008732@greed.delorie.com> <4096996E.9080700@gnu.org> <200405032210.i43MArI1021688@greed.delorie.com> <87wu3t9mca.fsf@egil.codesourcery.com> <200405032234.i43MYC1W022010@greed.delorie.com> In-Reply-To: <200405032234.i43MYC1W022010@greed.delorie.com> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-SW-Source: 2004-07/txt/msg00382.txt.bz2 [picking up a really old thread] >>Really, I don't see why this is better than a hardwired table >>> mapping CPU to floating point format. > > > Because most FPUs are IEEE, so except for the ones that aren't, it > will auto-detect the FPU type. Having a table means that CPUs default > to "broken", rather than defaulting to "probably works". > > It also means we don't have to keep tweaking the table as people > change their minds about CPU naming schemes This assume that the floatformat code works. Below is a table generated by using floatformat to convert the double 1.0 into the corresponding architecture format. Notice the arm_ext_big / arm_littlebyte_bigword and double_big / double_littlebyte_bigword pairs: 3f800000 floatformat_ieee_single_big 0000803f floatformat_ieee_single_little 3ff0000000000000 floatformat_ieee_double_big 000000000000f03f floatformat_ieee_double_little 3ff0000000000000 floatformat_ieee_double_littlebyte_bigword 0000000000000080ff3f floatformat_i387_ext 3fff8000000000000000 floatformat_m88110_ext 3fff00008000000000000000 floatformat_m68881_ext 0000000000000080ff3f0000 floatformat_i960_ext 00003fff8000000000000000 floatformat_arm_ext_big 00003fff8000000000000000 floatformat_arm_ext_littlebyte_bigword 3ff00000000000000000000000000000 floatformat_m88110_ext_harris 3fffe000000000000000000000000000 floatformat_ia64_spill_big 00000000000000000000000000e0ff3f floatformat_ia64_spill_little 3fff0000000000000000000000000000 floatformat_ia64_quad_big 0000000000000000000000000000ff3f floatformat_ia64_quad_little I'm withdrawing my patch. I'll instead fix this as MarkK suggested - local to GDB. Andrew