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Date: Tue, 4 Sep 2007 13:48:10 -0500
From: Scott Wood <scottwood@freescale.com>
To: Gabriel Paubert <paubert@iram.es>
Subject: Re: "atomic" 64-bit math on 32-bit ppc's?
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On Tue, Sep 04, 2007 at 01:39:37PM +0200, Gabriel Paubert wrote:
> That's wrong if lock is assigned to r0, you should use
> a "b" constraint to avoid this. Same for atomic_dec below.

GCC should really have removed r0 from the "r" class (it isn't truly a
general-purpose register), and had a different class meaning "r"-plus-r0.

-Scott