From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43)
	id 1J1hSv-0003i7-Aw
	for qemu-devel@nongnu.org; Mon, 10 Dec 2007 07:10:29 -0500
Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43)
	id 1J1hSt-0003gl-DT
	for qemu-devel@nongnu.org; Mon, 10 Dec 2007 07:10:28 -0500
Received: from [199.232.76.173] (helo=monty-python.gnu.org)
	by lists.gnu.org with esmtp (Exim 4.43) id 1J1hSs-0003gf-VM
	for qemu-devel@nongnu.org; Mon, 10 Dec 2007 07:10:27 -0500
Received: from honiara.magic.fr ([195.154.193.36])
	by monty-python.gnu.org with esmtps
	(TLS-1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.60)
	(envelope-from <l_indien@magic.fr>) id 1J1hSs-00027M-FY
	for qemu-devel@nongnu.org; Mon, 10 Dec 2007 07:10:26 -0500
Received: from [172.17.17.137] (gw.netgem.com [195.68.2.34])
	by honiara.magic.fr (8.13.1/8.13.1) with ESMTP id lBACAGjL031218
	for <qemu-devel@nongnu.org>; Mon, 10 Dec 2007 13:10:16 +0100
Subject: Re: [Qemu-devel] [PATCH][PPC] mtfsf: fix FPSCR_VX and FPSCR_FEX
	computation
From: Jocelyn Mayer <l_indien@magic.fr>
In-Reply-To: <20071210091318.GA3937@hall.aurel32.net>
References: <20071210091318.GA3937@hall.aurel32.net>
Content-Type: text/plain
Date: Mon, 10 Dec 2007 13:10:38 +0100
Message-Id: <1197288638.20253.45.camel@jma4.dev.netgem.com>
Mime-Version: 1.0
Content-Transfer-Encoding: 7bit
Reply-To: l_indien@magic.fr, qemu-devel@nongnu.org
List-Id: qemu-devel.nongnu.org
List-Unsubscribe: <http://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.gnu.org/pipermail/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <http://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: qemu-devel@nongnu.org


On Mon, 2007-12-10 at 10:13 +0100, Aurelien Jarno wrote:
> Hi all,

Hi,

> The patch below fix the computation of FPSCR_VX and FPSCR_FEX when
> using the mtfsf instruction. As stated in the PowerPC manual the mtfsf
> instruction can't alter those bit, and thus it should always be 
> computed.

You're right, the values are not computed properly.
I'll commit your fix.


> Index: target-ppc/op_helper.c
> ===================================================================
> RCS file: /sources/qemu/qemu/target-ppc/op_helper.c,v
> retrieving revision 1.73
> diff -u -d -p -r1.73 op_helper.c
> --- target-ppc/op_helper.c	24 Nov 2007 02:03:55 -0000	1.73
> +++ target-ppc/op_helper.c	10 Dec 2007 09:10:30 -0000
> @@ -888,12 +888,16 @@ void do_store_fpscr (uint32_t mask)
>      /* Update VX and FEX */
>      if (fpscr_ix != 0)
>          env->fpscr |= 1 << FPSCR_VX;
> +    else
> +        env->fpscr &= ~(1 << FPSCR_VX);
>      if ((fpscr_ex & fpscr_eex) != 0) {
>          env->fpscr |= 1 << FPSCR_FEX;
>          env->exception_index = POWERPC_EXCP_PROGRAM;
>          /* XXX: we should compute it properly */
>          env->error_code = POWERPC_EXCP_FP;
>      }
> +    else
> +        env->fpscr &= ~(1 << FPSCR_FEX);
>      fpscr_set_rounding_mode();
>  }
>  #undef WORD0

-- 
Jocelyn Mayer <l_indien@magic.fr>