modification to inline asm + 128 bit cop2 register support

[Denis Chertykov]

"Dylan Cuthbert" <dylan_cuthbert@hotmail.com> writes:

> (replying to Mike Stump from my home account)
> (this mail is really really way too long! sorry!)
> 
> I'll reply in three parts - the first part argues the case for my patch with 
> some undeniable logic (IMHO).  The second and third describe two problems 
> with the current compiler and the very latest chips that are coming 
> available.  The third situation would really be improved if someone would 
> help me with those darned machine description files.
> 
> >Mike Stump wrote:
> >This goes in the wrong direction I feel.  Instead, add support to
> >expose more of the assembly to the compiler, and have the compiler
> >generate the `more optimal' code.  I think you'll win better that way.
> >You can then have the full power of the optimizer to optimize.
> 
> 1. my case for "%A" to determine which_alternative in asm
> statements:

avr port already uses %A[0-9]
May be %W

Denis.