* tree-ssa.c (walk_use_def_chains_1): Make the visited map a
	pointer set instead of a bitmap.
	(walk_use_def_chains): Create, pass and clean up that pointer_set.

	* tree-ssa-alias.c (struct alias_info): Make the ssa_names_visited
	field an sbitmap.
	(init_alias_info): Allocate and zero it here.
	(delete_alias_info): Delete it here.
	(collect_points_to_info_for): Use it.

From-SVN: r90508