register hint usefulness

[Richard Henderson]

On Sun, Apr 23, 2000 at 08:20:02PM -0400, Richard Kenner wrote:
> I'm talking -O0 here: it shouldn't be doing *any* more work.

Incorrect.  Consider, for example, gcc.dg/clobbers.c. 

Local spills are absolutely necessary for correctness in that example. 
Of necessity I would assume local spilling is always going to be more
expensive than global spilling.  However, that's not to say that we
should not work to make things more efficient than they currently are.


r~