From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59619) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WTWlc-0007zo-3d for qemu-devel@nongnu.org; Fri, 28 Mar 2014 09:24:25 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WTWlT-0002Cu-Ap for qemu-devel@nongnu.org; Fri, 28 Mar 2014 09:24:15 -0400 Received: from mail-qc0-x22b.google.com ([2607:f8b0:400d:c01::22b]:60884) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WTWlT-0002Cq-61 for qemu-devel@nongnu.org; Fri, 28 Mar 2014 09:24:07 -0400 Received: by mail-qc0-f171.google.com with SMTP id c9so5864368qcz.2 for ; Fri, 28 Mar 2014 06:24:06 -0700 (PDT) Sender: Richard Henderson Message-ID: <533577ED.2010606@twiddle.net> Date: Fri, 28 Mar 2014 06:23:57 -0700 From: Richard Henderson MIME-Version: 1.0 References: <1394851732-25692-1-git-send-email-rth@twiddle.net> <1394851732-25692-12-git-send-email-rth@twiddle.net> <53354552.3060702@huawei.com> In-Reply-To: <53354552.3060702@huawei.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 11/26] tcg-aarch64: Reuse FP and LR in translated code List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Claudio Fontana , qemu-devel@nongnu.org, peter.maydell@linaro.org Cc: claudio.fontana@gmail.com On 03/28/2014 02:48 AM, Claudio Fontana wrote: > On 15.03.2014 03:48, Richard Henderson wrote: >> We don't need the FP within translated code, and the LR is >> otherwise unused. >> >> Signed-off-by: Richard Henderson > > The downside of this is that it disregards the procedure call standard from ARM. In what way do you believe the call standard to require a frame pointer? Certainly GCC avoids generating one when it isn't needed, so why should we? In any case, the real help comes in patch 14/26 where I implement the jit hook so that GDB can unwind through the code_gen_buffer. r~