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Date: Sat, 17 Nov 2007 11:14:19 +0100
From: "andrzej zaborowski" <balrogg@gmail.com>
Subject: Re: [Qemu-devel] qemu softmmu_template.h
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References: <E1ItKMw-0005h9-Aj@cvs.savannah.gnu.org>
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To: qemu-devel@nongnu.org

On 17/11/2007, J. Mayer <l_indien@magic.fr> wrote:
>
> On Sat, 2007-11-17 at 09:53 +0000, Andrzej Zaborowski wrote:
> > CVSROOT:      /sources/qemu
> > Module name:  qemu
> > Changes by:   Andrzej Zaborowski <balrog>     07/11/17 09:53:42
> >
> > Modified files:
> >       .              : softmmu_template.h
> >
> > Log message:
> >       Check permissions for the last byte first in unaligned slow_st accesses (patch from TeLeMan).
> >
> > CVSWeb URLs:
> > http://cvs.savannah.gnu.org/viewcvs/qemu/softmmu_template.h?cvsroot=qemu&r1=1.19&r2=1.20
> >
>
> Has it been checked that it's legal for all architectures and cannot
> have any nasty side effect to do accesses in the reverse order ? Real
> hardware do not ever seem to do this...

For real hardware the store is a single operation.

Logically it shouldn't have any side effects, but if it does then it
would rather mean that other code for that architecture is (also)
broken, I believe.

I've only tested ARM, mips, x86 and x86_64 before committing, so
please test. I figured that the patch won't get any comments on the
mailing list if it isn't merged.
Regards