Hello,

The attached converts the d10v to the new unwind mechanism.  It creates 
a new file:
	d10v-frame.[hc]
which implements a d10v specific frame unwinder.  The new file contains 
one obvious hack do_d10v_frame_pop() (that needs to be added to the 
standard set of unwind functions and purged of deprecated code), and 
still needs some d10v code cleanup (e.g., shouldn't need to specify the 
unused init_frame_extra_info).

In implementing this, the code adds frame-unwind.[hc] which implements a 
mechanims for maintaining registrary of frame unwinders and selecting 
one (is frame-unwinder, or frame-winder, or ..., better?).

Finally, it contains the change:

  get_frame_base (struct frame_info *fi)
  {
-  return fi->frame;
+  struct frame_id id = frame_id_unwind (fi->next);
+  return id.base;
  }

The issue is that, for a dummy frame, the code delays doing an unwind of 
the previous frame until it's rewuested.  This, unfortunatly, leaves the 
frame's base undefined.  A case of duplicating information finally 
comming back and biteing us.  The above is the correct fix.  Further, I 
think it highlights why I need to make `struct frame_info' opaque - so 
that this redundency can be eliminated.

Now to break this down into digestable chunks that can be reviewed for 
the mainline.

Andrew