Implementing TI mode (128-bit) and the 2nd pipeline for the MIPS R5900

[Woon yung Liu]

>You'll have to adjust FUNCTION_ARG and its counterpart for return values 

>to describe how to pass these 128 bit values around.

Thanks.

>Changing the word size to 128 bit should not be necessary.


I think that it would make things really non-standard anyway.
Thanks again.

>Many ports define patterns for operations on data types that are larger 
>than their native word mode.
>
>You really need to add the new patterns for operating on 128bit values 
>to the machine description and adjust the parameter passing routines .


I added some patterns, and will be adding more.
I'll adjust the parameter passing routine and ask here again if I encounter further problems.

> You define the registers & constraints normally.  However, you make the 

> registers conditional on the target in use.  ie, if you're not on an 
> r5900 target, then mark those registers as fixed.  That will prevent the 
> compiler from trying to use them on things other than the r5900.
>
> Again, you may want to find the old cygnus releases of the r5900 
> toolchain.  It had functional access to the second hi/lo register pair.


Thanks for your input. I'll try to find the way to set those registers as fixed.