re PR tree-optimization/58513 (*var and MEM[(const int &)var]  (var has int* type) are not treated as the same data ref.)

2013-09-24  Richard Biener  <rguenther@suse.de>

	PR middle-end/58513
	* tree.c (reference_alias_ptr_type): Move ...
	* alias.c (reference_alias_ptr_type): ... here and implement
	in terms of the new reference_alias_ptr_type_1.
	(ref_all_alias_ptr_type_p): New helper.
	(get_deref_alias_set_1): Drop flag_strict_aliasing here,
	use ref_all_alias_ptr_type_p.
	(get_deref_alias_set): Add flag_strict_aliasing check here.
	(reference_alias_ptr_type_1): New function, split out from ...
	(get_alias_set): ... here.
	(alias_ptr_types_compatible_p): New function.
	* alias.h (reference_alias_ptr_type): Declare.
	(alias_ptr_types_compatible_p): Likewise.
	* tree.h (reference_alias_ptr_type): Remove.
	* fold-const.c (operand_equal_p): Use alias_ptr_types_compatible_p
	to compare MEM_REF alias types.

	* g++.dg/vect/pr58513.cc: New testcase.

From-SVN: r202865