From owner-freebsd-arch Wed Feb 6 14:41:20 2002 Delivered-To: freebsd-arch@freebsd.org Received: from h132-197-179-27.gte.com (h132-197-179-27.gte.com [132.197.179.27]) by hub.freebsd.org (Postfix) with ESMTP id DEBD237B405 for ; Wed, 6 Feb 2002 14:41:13 -0800 (PST) Received: from kanpc.gte.com (localhost [127.0.0.1]) by h132-197-179-27.gte.com (8.11.6/8.11.6) with SMTP id g16Mew129115; Wed, 6 Feb 2002 17:40:58 -0500 (EST) (envelope-from ak03@gte.com) Date: Wed, 6 Feb 2002 17:40:58 -0500 From: Alexander Kabaev To: Daniel Eischen Cc: peter@wemm.org, eischen@vigrid.com, arch@FreeBSD.ORG Subject: Re: getsetcontext system call Message-Id: <20020206174058.60c8cf14.ak03@gte.com> In-Reply-To: References: <20020206195918.6350039F1@overcee.wemm.org> Organization: Verizon Data Services X-Mailer: Sylpheed version 0.7.0claws49 (GTK+ 1.2.10; i386--freebsd5.0) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-freebsd-arch@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG > As to set_fpregs(), it looks like it wants to convert an x87 > FPU state to an SSE FPU state. The opposite seems to be the > case for fill_fpregs(). I'm not exactly sure how and why > fill_fpregs() and set_fpregs() are used. Since we make struct > fpreg large enough to hold either x87 or SSE FPU state, do we > even care about converting between the two different formats > any longer? These functions are used by ptrace and consequently by GDB. GDB expects to get floating point register state in predictable format regardless of whether SSE has been enabled in CPU or not. Linux also adds new GET/SET_FPXREGS requests to get complete SSE floating point registers for use by SSE aware debuggers. As far as I can tell, GDB 5.x is using these new requests on Linux, while 4.18 doesn't. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-arch" in the body of the message