Introduce TARGET_SUPPORTS_ALIASES

Introduce TARGET_SUPPORTS_ALIASES

2017-08-11  Martin Liska  <mliska@suse.cz>

	* c-opts.c (c_common_post_options): Replace ASM_OUTPUT_DEF with
	TARGET_SUPPORTS_ALIASES.
2017-08-11  Martin Liska  <mliska@suse.cz>

	* asan.c (asan_protect_global): Replace ASM_OUTPUT_DEF with
	TARGET_SUPPORTS_ALIASES.
	* cgraph.c (cgraph_node::create_same_body_alias): Likewise.
	* ipa-visibility.c (can_replace_by_local_alias): Likewise.
	(optimize_weakref): Likewise.
	* symtab.c (symtab_node::noninterposable_alias): Likewise.
	* varpool.c (varpool_node::create_extra_name_alias): Likewise.
	* defaults.h: Introduce TARGET_SUPPORTS_ALIASES.
2017-08-11  Martin Liska  <mliska@suse.cz>

	* decl2.c (get_tls_init_fn): Replace ASM_OUTPUT_DEF with
	TARGET_SUPPORTS_ALIASES.
	(handle_tls_init): Likewise.
	(note_mangling_alias): Likewise.  Remove ATTRIBUTE_UNUSED for
	both arguments.
	* optimize.c (can_alias_cdtor): Likewise.

From-SVN: r251048