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From: Segher Boessenkool <segher@kernel.crashing.org>
Subject: Re: [PATCH] atomic_dec_if_positive sign extension fix
Date: Mon, 15 Jan 2007 17:01:12 +0100
To: Gabriel Paubert <paubert@iram.es>
Cc: olof@lixom.net, linuxppc-dev@ozlabs.org, Paul Mackerras <paulus@samba.org>
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> It also avoids clobbering the carry, you don't know whether a future
> version of GCC will require explicit clobbers for the carry. For now
> they are useless: you can specify "xer" in the clobber list AFAIR but
> no pattern can be split between setters and users of the carry in the
> machine description.

You can specify "cc" in the clobber list already, don't use
"xer" unless you're clobbering something else in the XER.


Segher