2013-05-02  Richard Biener  <rguenther@suse.de>

	* graphds.h (struct graph): Add obstack member.
	* graphds.c (new_graph): Initialize obstack and allocate
	vertices from it.
	(add_edge): Allocate edge from the obstack.
	(free_graph): Free the obstack instead of all edges and
	vertices.

From-SVN: r198539