From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Jan Beulich" <jbeulich@novell.com>
Subject: Re: [PATCH] x86 emulation: fix bswap
Date: Thu, 15 Feb 2007 11:37:05 +0000
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	<C1F9E768.9744%Keir.Fraser@cl.cam.ac.uk>
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>>> Keir Fraser <Keir.Fraser@cl.cam.ac.uk> 15.02.07 11:33 >>>
>On 15/2/07 10:22, "Jan Beulich" <jbeulich@novell.com> wrote:
>
>> REX.R needs to be decoded and since bswap on a 16-bit operand is undefined,
>> it is best to have hardware execute this so the emulation result matches
>> hardware behavior. Since it is simple to do, faster, and smaller, also let
>> hardware do 32- and 64-bit ones.
>
>Can 'undefined' behaviour include e.g. #UD?

I don't think so.

Jan