Re: Using PPC asm (from Linux kernel) in xine

[Michel Lanners <mlan@cpu.lu>]

On  22 May, this message from Albert D. Cahalan echoed through cyberspace:
> =?iso-8859-1?Q?Rog writes:
[abot fast memcopy in asm]
> 
>   dcbt  eight,src        /* prefetch the next cache line */
> loop_top:
>   dcba  eight,dst        /* allocate a cache line */
>   lfd   f11,8,(src)
>   lfd   f12,16,(src)
>   lfd   f13,24,(src)
>   lfdu  f14,32,(src)
              ^^
   These should probably be 0,8,16 and 24... same goes below.

>   dcbi  r0,src           /* would like to discard the src data */
>   dcbt  eight,src        /* prefetch the next cache line */
>   stfd  f11,8,(dst)
>   stfd  f12,16,(dst)
>   stfd  f13,24,(dst)
>   stfdu f14,32,(dst)
>   dcbf  r0,dst           /* write back if needed, then invalidate */

And don't forget the loop counter and some increment... Or code it with
a decrement operator and copy backwards?

> bdnz  loop_top
> 
> BLAH, BLAH...

Michel

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