Put back the original version, optimized for x86.

	   (let ((s (xoro-random-state-state rng-state)))

	     (declare (type (simple-array double-float (2)) s))

	     (multiple-value-bind (r1 r0)

		 (xoroshiro-next-portable s)

		 (xoroshiro-next s)

	       (setf (xoro-random-state-rand rng-state) r0)

	       (setf (xoro-random-state-cached-p rng-state) t)

	       r1))))))

(defun xoroshiro-next-portable (state)

#-x86

(defun xoroshiro-next (state)

  (declare (type (simple-array double-float (2)) state))

  (flet ((rotl-55 (x1 x0)

	   (declare (type (unsigned-byte 32) x0 x1)