anchor.diff:      t))
   
   #+x86-64
  -(sys.int::define-lap-function %%bitblt-row ((to-base from-base ncols))
  +(sys.int::define-lap-function %%bitblt-row-x8r8g8b8 ((to-base from-base ncols))
     (sys.lap-x86:mov64 :rdi :r8) ; to-storage
     (sys.lap-x86:mov64 :rsi :r9) ; from-storage
     (sys.lap-x86:mov64 :rcx :r10) ; ncols
  
positive.code:                     (to-base (convert-to-pmap-address
                                (+ (framebuffer-base-address fb)
                                   (* *debug-video-y* (framebuffer-pitch fb))
                                   (* *debug-video-x* 4)
                                   (* *debug-video-col* col-width 4))))
                      (to-pitch (framebuffer-pitch fb))
                      (from-base (+ (sys.int::lisp-object-address blob) (- sys.int::+tag-object+) 8))
                      (from-pitch (* 8 4)))
                 (dotimes (i 8)
                   (%%bitblt-row to-base from-base 8)
                   (incf to-base to-pitch)
                   (incf from-base from-pitch))
                 (incf *debug-video-x* 8)
  
negative.code: 
  (defun video-set-framebuffer (phys width height pitch layout damage-fn)
    (debug-print-line "Configured new framebuffer at " phys "  " width "x" height "  layout " layout "  pitch " pitch)
    (multiple-value-bind (bytes-per-pixel blit-fn fill-fn)
        (ecase layout
          (:x8r8g8b8 (values 4 #'%%bitblt-row-x8r8g8b8 #'%%bitset-row-x8r8g8b8))
          (:r8g8b8   (values 3 #'%%bitblt-row-r8g8b8   #'%%bitset-row-r8g8b8)))
      (setf *current-framebuffer* (make-framebuffer :base-address phys
                                                    :width width
                                                    :height height
                                                    :bytes-per-pixel bytes-per-pixel
                                                    :pitch pitch
                                                    :layout layout
                                                    :damage-fn (or damage-fn
                                                                   'framebuffer-dummy-damage)
                                                    :blit-fn blit-fn
                                                    :fill-fn fill-fn)))
    (set-run-light t))
  
  (defun current-framebuffer ()
  