From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1FOzQU-0005Rt-FK for qemu-devel@nongnu.org; Thu, 30 Mar 2006 10:51:10 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1FOzQT-0005Rh-P4 for qemu-devel@nongnu.org; Thu, 30 Mar 2006 10:51:10 -0500 Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1FOzQT-0005Re-Ls for qemu-devel@nongnu.org; Thu, 30 Mar 2006 10:51:09 -0500 Received: from [65.74.133.6] (helo=mail.codesourcery.com) by monty-python.gnu.org with esmtps (TLS-1.0:DHE_RSA_AES_256_CBC_SHA:32) (Exim 4.52) id 1FOzSf-0005cZ-SA for qemu-devel@nongnu.org; Thu, 30 Mar 2006 10:53:26 -0500 From: Paul Brook Subject: Re: [Qemu-devel] Missing ARMv6 instructions? Date: Thu, 30 Mar 2006 16:50:48 +0100 References: <200603292301.41791.paul@codesourcery.com> <20060330143030.GA23929@mail.shareable.org> <20060330152524.GA29791@xi.wantstofly.org> In-Reply-To: <20060330152524.GA29791@xi.wantstofly.org> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200603301650.49994.paul@codesourcery.com> Reply-To: qemu-devel@nongnu.org List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org > Note that the new ARM ABI being pushed by ARM ltd, which is called > EABI, mandates using a thumb-related instruction (bx) in the function > exit path. No it doesn't. The EABI mandates that code be interworking safe. It's possible to implement this is an way that only uses bx when actually returning to Thumb code, ie when you already know your hardware supports bx. In practice many distros may assume Thumb capable hardware in the same way many x86 distros assume at least i486 or i686, but that's an entirely different issue. Paul