Probing for native availability of isel from userspace

[Segher Boessenkool]

>> That's for 64-bit; another good option for 64-bit is to just never  
>> use
>> isel, it hardly ever buys you anything.  It is much more useful on  
>> the
>> (older) 32-bit cores that support it.
>
> Why is it more useful on 32-bit?  If you're referring to the  
> performance of specific cores rather than some architectural thing,  
> maybe that's true with some chips, but on the Freescale side I'd be  
> surprised if e5500 were much different from e500v2 in that regard.

Yes, I was talking about the older cores.  I'd be surprised if ISEL is
often a win on e5500, but I don't really know.  I forgot about that chip
to tell you the truth :-)


Segher