mmix.md ("nonlocal_goto_receiver"): Refer to the frame-pointer as an operand.

mmix.md ("nonlocal_goto_receiver"): Refer to the frame-pointer as an operand.

	* config/mmix/mmix.md ("nonlocal_goto_receiver"): Refer to the
	frame-pointer as an operand.
	("*nonlocal_goto_receiver_expanded"): Ditto.  Use
	mmix_output_register_setting instead of naked output_asm_insn for
	the offset from the frame-pointer to the saved rO.
	* config/mmix/mmix.c (mmix_output_register_setting): Emit NEGU for
	values -255..0.
	* config/mmix/predicates.md ("frame_pointer_operand"): New.
	* config/mmix/constraints.md ("Yf"): New.

From-SVN: r192677