anchor.diff:  (defun frame-decode (frame)
     "Decode a frame destructively modifying (and garbaging) all subframes within.
   Returns list of decoded audio buffers (one buffer for each channel)."
  -  (declare (optimize (speed 3)
  -		     (safety 0)))
  -
     (let ((decoded-subframes
   	 (mapcar #'(lambda (subframe) (subframe-decode subframe frame))
   		 (frame-subframes frame)))
  
positive.code: (defmacro gen-lpc-predictor (n)
    "Generate FIR linear predictor of order N"
    `(flet ((lpc-predictor (subframe)
              (declare (optimize (speed 3)
                                 (safety 0)))
              (let ((out-buf (subframe-out-buf subframe))
                    (shift (subframe-lpc-coeff-shift subframe))
                    (coeff (subframe-lpc-predictor-coeff subframe)))
  
negative.code: 
  (defmethod subframe-decode ((subframe subframe-fixed) frame)
    ;; Decodes subframe destructively modifiying it
    (declare (ignore frame))
    (let* ((out-buf (subframe-out-buf subframe))
  	 (order (subframe-order subframe))
  	 (len (length out-buf)))
  