re PR tree-optimization/36345 (TBAA-pruning of points-to sets ineffective)

re PR tree-optimization/36345 (TBAA-pruning of points-to sets ineffective)

2008-06-12  Richard Guenther  <rguenther@suse.de>

	PR tree-optimization/36345
	* tree-flow.h (struct ptr_info_def): Align escape_mask,
	add memory_tag_needed flag.
	(may_alias_p): Declare.
	* tree-ssa-alias.c (may_alias_p): Export.
	(set_initial_properties): Use memory_tag_needed flag.
	(update_reference_counts): Likewise.
	(reset_alias_info): Reset memory_tag_needed flag.
	(create_name_tags): Check memory_tag_needed flag.
	(dump_points_to_info_for): Dump it.
	* tree-ssa-structalias.c (struct variable_info): Remove
	directly_dereferenced flag.
	(new_var_info): Do not initialize it.
	(process_constraint_1): Do not set it.
	(update_alias_info): Set is_dereferenced flag.
	(set_uids_in_ptset): Use may_alias_p.
	(set_used_smts): Check memory_tag_needed flag.
	(find_what_p_points_to): Likewise.  Pass is_dereferenced flag.
	* tree-ssa-alias.c (verify_flow_sensitive_alias_info): Check
	memory_tag_needed flag.
	* tree-ssa-alias-warnings.c (dsa_named_for): Try to recover
	from broken design.

	* gcc.c-torture/execute/20020619-1.c: Remove broken part of
	the testcase.

From-SVN: r136695