* target.def (call_args, end_call_args): New hooks.
	* hooks.c (hook_void_rtx_tree): New empty function.
	* hooks.h (hook_void_rtx_tree): Declare.
	* doc/tm.texi.in (TARGET_CALL_ARGS, TARGET_END_CALL_ARGS): Add.
	* doc/tm.texi: Regenerate.
	* calls.c (expand_call): Slightly rearrange the code.  Use the two new
	hooks.
	(expand_library_call_value_1): Use the two new hooks.

From-SVN: r217199