;;; -*- Mode:LISP; Package:LISP-INTERNALS; Base:10; Readtable:CL -*-


(defun create-n (n)
       (do ((n n (1- n))
	    (a () (push () a)))
	   ((= n 0) a)))

(defun div2 (l)
       (do ((l l (cddr l))
	    (a () (push (car l) a)))
	   ((null l) a)))

(defun dv2 (l)
       (cond ((null l) ())
	     (t (cons (car l) (dv2 (cddr l))))))

(defun test1 (l)
       (do ((i 300. (1- i)))
	   ((= i 0))
	   (div2 l)
	   (div2 l)
	   (div2 l)
	   (div2 l)))

(defun test2 (l)
       (do ((i 300. (1- i)))
	   ((= i 0))
	   (dv2 l)
	   (dv2 l)
	   (dv2 l)
	   (dv2 l)))

(defun test-div2 ()
  (let ((l (create-n 200.)))
    (hw:write-microsecond-clock (hw:unboxed-constant 0))
    (error "DIV2-ITERATIVE"
	   (test1 l) (hw:read-microsecond-clock))
    (hw:write-microsecond-clock (hw:unboxed-constant 0))
    (error "DIV2-RECURSIVE"
	   (test2 l) (hw:read-microsecond-clock))
    (loop)))