Use predicates for RTL objects

[Ben Elliston]

> Do people still want (GET_CODE (rtx) == XXX) cleaned up to XXX_P(RTX).

I would think so -- did you get that from the beginner's project list?

> I would probably do all the plus/minus stuff first. Submit that as a patch.

Sure.  Please read the patch submission guidelines before starting.

> ps. Do I just send the diff file to this mailing list?

No, gcc-patches.

Cheers, Ben