2006-10-19  Daniel Berlin  <dberlin@dberlin.org>

	Fix PR tree-optimization/28778
	Fix PR tree-optimization/29156
	Fix PR tree-optimization/29415
	* tree.h (DECL_PTA_ARTIFICIAL): New macro.
	(tree_decl_with_vis): Add artificial_pta_var flag.
	* tree-ssa-alias.c (is_escape_site): Remove alias info argument,
	pushed into callers.
	* tree-ssa-structalias.c (nonlocal_for_type): New variable.
	(nonlocal_all): Ditto.
	(struct variable_info): Add directly_dereferenced member.
	(var_escaped_vars): New variable.
	(escaped_vars_tree): Ditto.
	(escaped_vars_id): Ditto.
	(nonlocal_vars_id): Ditto.
	(new_var_info): Set directly_dereferenced.
	(graph_size): New variable
	(build_constraint_graph): Use graph_size.
	(solve_graph): Don't process constraints that cannot change the
	solution, don't try to propagate an empty solution to our
	successors.
	(process_constraint): Set directly_dereferenced.
	(could_have_pointers): New function.
	(get_constraint_for_component_ref): Don't process STRING_CST.
	(nonlocal_lookup): New function.
	(nonlocal_insert): Ditto.
	(create_nonlocal_var): Ditto.
	(get_nonlocal_id_for_type): Ditto.
	(get_constraint_for): Allow results vector to be empty in the case
	of string constants.
	Handle results of calls properly.
	(update_alias_info): Update alias info stats on number and type of
	calls.
	(find_func_aliases): Use could_have_pointers.
	(make_constraint_from_escaped): Renamed from
	make_constraint_to_anything, and changed to make constraints from
	escape variable.
	(make_constraint_to_escaped): New function.
	(find_global_initializers): Ditto.
	(create_variable_info_for): Make constraint from escaped to any
	global variable, and from any global variable to the set of
	escaped vars.
	(intra_create_variable_infos): Deal with escaped instead of
	pointing to anything.
	(set_uids_in_ptset): Do type pruning on directly dereferenced
	variables.
	(find_what_p_points_to): Adjust call to set_uids_with_ptset.
	(init_base_vars): Fix comment, and initialize escaped_vars.
	(need_to_solve): Removed.
	(find_escape_constraints): New function.
	(expand_nonlocal_solutions): Ditto.
	(compute_points_to_sets): Call find_escape_constraints and
	expand_nonlocal_solutions.
	(delete_points_to_sets): Don't fall off the end of the graph.
	(init_alias_heapvars): Initialize nonlocal_for_type and
	nonlocal_all.
	(delete_alias_heapvars): Free nonlocal_for_type and null out
	nonlocal_all.

From-SVN: r117891