From mboxrd@z Thu Jan  1 00:00:00 1970
From: Samuel Thibault <samuel.thibault@eu.citrix.com>
Subject: Re: [PATCH] x86: fix variable_test_bit() asmconstraints
Date: Fri, 14 Mar 2008 13:59:38 +0000
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To: Jan Beulich <jbeulich@novell.com>
Cc: xen-devel@lists.xensource.com, Keir Fraser <keir.fraser@eu.citrix.com>
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Jan Beulich, le Fri 14 Mar 2008 13:51:26 +0000, a écrit :
> >memory-clobber would be needed for the atomic ops, but a dummy memory
> >operand would suffice for non-atomic ops. I used memory clobber everywhere
> 
> Atomic ops imply a barrier (otherwise the compiler can defeat the
> purpose of the atomic operation). The non-atomic ones don't need a
> dummy operand, but one that precisely describes the place in memory
> that changes.

Mmm, won't that unnecessarily make the compiler put code to compute that
place?

Samuel