* tc-sparc.c (default_arch_size): New static local.

	* tc-sparc.c (default_arch_size): New static local.
	(struct sparc_arch): Rename arch_size to default_arch_size.
	New member user_option_p.
	(sparc_arch_table): Always include v9, v9a.  New entry v9-64.
	(init_default_arch): Check whether default arch is valid.
	Set default_arch_size in addition to sparc_arch_size.
	(OPTION_32,OPTION_64): Define.
	(md_longopts): New entries for -32, -64.
	(md_parse_option): Handle them.
	(md_show_usage): Print them.  Ensure init_default_arch called.