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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 00:43:43 +0100
To: Segher Boessenkool <segher@kernel.crashing.org>
Cc: olof@lixom.net, linuxppc-dev@ozlabs.org, Paul Mackerras <paulus@samba.org>
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> What is this function supposed to do if it gets 0x80000000 as
> input btw?  The current code happily makes it 0x7fffffff as
> far as I can see?  The "rlwinm" thing would fix that ;-)  (Or
> unfix, if the current behaviour is intended).

...except it doesn't change behaviour on 32-bit of
course.  Forget it, do one of the other suggested
things instead please :-)


Segher