Register classes

[Daniel Berlin]

On Aug 19, 2004, at 9:53 PM, James E Wilson wrote:

> Daniel Berlin wrote:
>> A whole lot of ports seem to have register classes that contain 
>> registers that can't possibly be used together.
>> They also have to seem weird groupings of registers that don't make 
>> sense to be used by any single pseudo.
>
> This is because of interactions between the register preferences 
> computed by regclass and the register allocator.
>
IOW, it's done to try to get better performance out of the register 
allocator.
:)
--Dan