PR lto/64374
	* target.def (target_option_stream_in): New target hook.
	* tree-streamer-in.c (streamer_read_tree_bitfields): Invoke
	targetm.target_option.post_stream_in if non-NULL.
	* doc/tm.texi.in: Add @hook TARGET_OPTION_POST_STREAM_IN.
	* doc/tm.texi: Updated.
	* config/i386/i386.c (ix86_function_specific_post_stream_in): New
	function.
	(TARGET_OPTION_POST_STREAM_IN): Redefine.

From-SVN: r220958