2010-10-22  Richard Guenther  <rguenther@suse.de>

	* gimple.h (gimple_register_canonical_type): Declare.
	* gimple.c (gimple_canonical_types): New global hashtable.
	(struct gimple_type_leader_entry_s): New type.
	(gimple_type_leader): New global cache.
	(gimple_lookup_type_leader): New function.
	(gtc_visit): Query the proper cache.
	(gimple_types_compatible_p): Likewise.
	(gimple_register_type): Use the new cache instead of TYPE_CANONICAL.
	(gimple_canonical_type_eq): New function.
	(gimple_register_canonical_type): Likewise.
	(print_gimple_types_stats): Adjust for gimple_canonical_types.
	(free_gimple_type_tables): Likewise.  Free gimple_type_leader.
	* tree-ssa.c (useless_type_conversion_p): Do not dispatch to
	gimple_types_compatible_p for LTO.

	lto/
	* lto.c (lto_fixup_type): Fixup TYPE_CANONICAL again, via
	the new gimple_register_canonical_type.

From-SVN: r165848