* builtin-types.def (BT_FN_VOID_PTR_INT_INT): New.
	* builtins.def (BUILT_IN_PREFETCH): New.
	* builtins.c (expand_builtin_expect): New.
	  (expand_builtin): Call it.
	* doc/extend.texi: Document __builtin_expect.

From-SVN: r47582