LOOP - Decrement CX and Loop if CX Not Zero

	Usage:	LOOP	label
	Modifies flags: None


	Decrements CX by 1 and transfers control to "label" if CX is not
	Zero.  The "label" operand must be within -128 or 127 bytes of the
	instruction following the loop instruction


				 Clocks			Size
	Operands	 808x  286   386   486		Bytes

	label:	jump	  18   8+m  11+m    6		  2
		no jump	   5	4     ?	    2


	- see Instruction Timing