From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:42449) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ayikJ-0007Js-1l for qemu-devel@nongnu.org; Fri, 06 May 2016 12:37:01 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ayik7-0000Ov-Ep for qemu-devel@nongnu.org; Fri, 06 May 2016 12:36:49 -0400 Received: from mail-qk0-x22d.google.com ([2607:f8b0:400d:c09::22d]:36351) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ayik6-0000KM-6P for qemu-devel@nongnu.org; Fri, 06 May 2016 12:36:43 -0400 Received: by mail-qk0-x22d.google.com with SMTP id x7so62948531qkd.3 for ; Fri, 06 May 2016 09:36:28 -0700 (PDT) Sender: Richard Henderson References: <1462392752-17703-1-git-send-email-laurent@vivier.eu> <1462392752-17703-5-git-send-email-laurent@vivier.eu> From: Richard Henderson Message-ID: <0460d1ff-18f3-3b01-6b3e-36ca9fc37c08@twiddle.net> Date: Fri, 6 May 2016 06:36:20 -1000 MIME-Version: 1.0 In-Reply-To: <1462392752-17703-5-git-send-email-laurent@vivier.eu> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Subject: Re: [Qemu-devel] [PATCH 04/52] target-m68k: manage scaled index List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Laurent Vivier , qemu-devel@nongnu.org Cc: gerg@uclinux.org, schwab@linux-m68k.org, agraf@suse.de On 05/04/2016 10:11 AM, Laurent Vivier wrote: > Scaled index is not supported by 68000, 68008, and 68010. > > EA = (bd + PC) + Xn.SIZE*SCALE + od > > Ignore it: > > M68000 FAMILY PROGRAMMER’S REFERENCE MANUAL > 2.4 BRIEF EXTENSION WORD FORMAT COMPATIBILITY > > "If the MC68000 were to execute an instruction that > encoded a scaling factor, the scaling factor would be > ignored and would not access the desired memory address. > The earlier microprocessors do not recognize the brief > extension word formats implemented by newer processors. > Although they can detect illegal instructions, they do not > decode invalid encodings of the brief extension word formats > as exceptions." > > Signed-off-by: Laurent Vivier > --- > target-m68k/translate.c | 5 +++++ > 1 file changed, 5 insertions(+) Reviewed-by: Richard Henderson r~