Subject: Re: [PATCH] powerpc: Optimise the 64bit optimised __clear_user

From: Benjamin Herrenschmidt <[email-masked]>
Date: Thu, 07 Jun 2012 16:39:33 +1000

On Thu, 2012-06-07 at 16:05 +1000, Michael Neuling wrote:

> One problem with this is when we construct the instructions, like using
> anything from ppc-opcode.h.  eg. using PPC_POPCNTB would need to go from:
>     PPC_POPCNTB(r3,r3) 
> to:
>     PPC_POPCNTB(3,3) 
> Which is less readable IMHO.

Yes, I know. Not much to do about this, but it might still be worth it,
how much time wasted due to mixing up or with ori in asm somewhere ?

One option would be to #define R3 (or _r3) for use in those macros so
we still have something nicer than just "3"... oh well.

Cheers,
Ben.