Re: [RFC] CFG hooks for rtl/tree specificities

["Pop Sébastian" <pop@gauvain.u-strasbg.fr>]

On Tue, Apr 01, 2003 at 05:46:07PM +0200, Jan Hubicka wrote:
> 
> This looks nice.
> It would be interesting to think about what operations do we really need
> - for instance split_edge should be probably implementable already via
> the primitive operations (basic block creation, edge redirection).  Our

Yes, the split_edge function is trivially implemented at the tree level:

basic_block
tree_split_edge (edge_in)
     edge edge_in;
{
  basic_block new_bb, dest;
  
  /* Abnormal edges cannot be split.  */
  if (edge_in->flags & EDGE_ABNORMAL)
    abort ();
  
  dest = edge_in->dest;
  new_bb = create_bb ();
  redirect_edge_succ  (edge_in, new_bb);
  make_edge (new_bb, dest, EDGE_FALLTHRU);
  return new_bb;
}

except "create_bb" all the other functions are CFG generic, making the split_edge
a good candidate for the CFG API.  At RTL level the split_edge function deals
with insns at this moment.

> current API is not 100% ready for that so we will probably need cleanup
> on the way.
> 
> I would be happy about switching to the hooks first and leaving it to me
> to cleanup the APIs if you preffer.
> 
Yes, thanks.

Sebastian