* hooks.c (hook_bool_tree_true): New.
	(hook_rtx_tree_int_null): New.
	(hook_rtx_rtx_null): Use NULL, not 0.
	* hooks.h: Add 'extern' to everything.
	(hook_bool_tree_true): New.
	(hook_rtx_tree_int_null): New.
	* targhooks.c (hook_bool_CUMULATIVE_ARGS_true): New.
	* targhooks.h (hook_bool_CUMULATIVE_ARGS_true): New.
	* config/rs6000/rs6000-protos.h (setup_incoming_varargs): Remove
	prototype.
	* config/rs6000/rs6000.c (rs6000_return_in_memory): New.
	(setup_incoming_varargs): Prototype.
	(TARGET_PROMOTE_FUNCTION_ARGS): Define.
	(TARGET_PROMOTE_FUNCTION_RETURN): Define.
	(TARGET_STRUCT_VALUE_RTX): Define.
	(TARGET_RETURN_IN_MEMORY): Define.
	(TARGET_SETUP_INCOMING_VARARGS): Define.
	(TARGET_STRICT_ARGUMENT_NAMING): Define.
	(TARGET_PRETEND_OUTGOING_VARARGS_NAMED): Define.
	(init_cumulative_args): Use rs6000_return_in_memory.
	(setup_incoming_varargs): Make 'static'.
	* config/rs6000/rs6000.h (PROMOTE_FUNCTION_ARGS): Delete.
	(PROMOTE_FUNCTION_RETURN): Delete.
	(STRUCT_VALUE): Delete.
	(RETURN_IN_MEMORY): Delete.
	(SETUP_INCOMING_VARARGS): Delete.

From-SVN: r72197