[PATCH] powerpc: Optimise the 64bit optimised __clear_user

[Benjamin Herrenschmidt]

On Wed, 2012-06-06 at 18:40 +0200, Segher Boessenkool wrote:
> > +err1;	dcbz	r0,r3
> 
> There is no such instruction, you probably meant "dcbz 0,r3"?

This reminds me... what would happen if we changed all our

#define	r0	0
#define	r1	1

etc... to:

#define r0	%r0
#define r1	%r1

?

I'm thinking it might help catch that sort of nasties (and some of them
can be really nasty, such as inverting mfspr/mtspr arguments, or vs ori,
etc... ). I'm sure we'd have a problem with a few macros & inline
constructs but nothing we can't fix..

(Haven't tested ... still home, officially sick :-)

Cheers,
Ben.