From owner-freebsd-current@FreeBSD.ORG Fri Aug 5 15:58:55 2005 Return-Path: X-Original-To: freebsd-current@freebsd.org Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id DA2E016A41F for ; Fri, 5 Aug 2005 15:58:55 +0000 (GMT) (envelope-from sgk@troutmask.apl.washington.edu) Received: from troutmask.apl.washington.edu (troutmask.apl.washington.edu [128.208.78.105]) by mx1.FreeBSD.org (Postfix) with ESMTP id B46BF43D58 for ; Fri, 5 Aug 2005 15:58:53 +0000 (GMT) (envelope-from sgk@troutmask.apl.washington.edu) Received: from troutmask.apl.washington.edu (localhost [127.0.0.1]) by troutmask.apl.washington.edu (8.13.4/8.13.4) with ESMTP id j75FwhVV004221; Fri, 5 Aug 2005 08:58:43 -0700 (PDT) (envelope-from sgk@troutmask.apl.washington.edu) Received: (from sgk@localhost) by troutmask.apl.washington.edu (8.13.4/8.13.1/Submit) id j75Fwcre004220; Fri, 5 Aug 2005 08:58:38 -0700 (PDT) (envelope-from sgk) Date: Fri, 5 Aug 2005 08:58:38 -0700 From: Steve Kargl To: Peter Jeremy Message-ID: <20050805155838.GA4147@troutmask.apl.washington.edu> References: <20050804162618.GA96657@troutmask.apl.washington.edu> <20050804191547.GB2104@cirb503493.alcatel.com.au> <20050804193030.GA97987@troutmask.apl.washington.edu> <20050805074916.GD2104@cirb503493.alcatel.com.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20050805074916.GD2104@cirb503493.alcatel.com.au> User-Agent: Mutt/1.4.2.1i Cc: freebsd-current@freebsd.org Subject: Re: Number of significand bits in long double? X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 05 Aug 2005 15:58:56 -0000 On Fri, Aug 05, 2005 at 05:49:16PM +1000, Peter Jeremy wrote: > Long double on various FreeBSD architectures is: > Alpha: 53 bits (no hardware long double) > ARM: 53 bits (not sure if ARM supports anything else) > amd64: 64 bits (can be restricted to 24 or 53 bits) > i386: 64 bits (can be restricted to 24 or 53 bits) > iA64: 64 bits > PPC: 53 bits (though I believe the h/w supports 106 or 112 bits) > SPARC: 113 bits Thanks for the info. The code I've written should work on all of the above with the exception of sparc. I don't have access to that hardware, so I won't be writing code for sparc. > IMHO, it would be nice to run the i386 in native precision but that > opens up a can of worms (since expressions will wind up being > evaluated in different precisions depending on whether the compiler > needs to spill registers onto the stack and whether temporary > variables are registers or stack). I'm aware of these worms. > You probably need to have a chat to bde@ I have a whole mailbox full of bde emails concerning the polynomial approximations. -- Steve