anchor.diff:  
   ;;; Instructions
   
  -(defconstant insn-size-suffix '("b" "w" "l" "q"))
  -(define usual-size-suffix (elt insn-size-suffix value-scale))
  +(define (insn-size-suffix scale)
  +  (elt '("b" "w" "l" "q") scale))
  +
  +(defconstant value-insn-size-suffix (insn-size-suffix value-scale))
   
   (defmarco (define-insn-2 name insn)
     (quasiquote
  
positive.code: (define (emit-insn-2 out insn src dest scale)
    (unless scale
      (set! scale value-scale))
    (emit out "~A~A ~A, ~A" insn (elt insn-size-suffix scale)
          (funcall src scale) (funcall dest scale)))
  
  (define-insn-2 emit-mov "mov")
  
negative.code:   (quasiquote
      (define ((unquote name) out . scale)
        (emit out "~A~A" (unquote insn)
              (insn-size-suffix (if scale (car scale) value-scale))))))
  
  (define-insn-0 emit-rep-movs "rep ; movs")
  (define-insn-0 emit-pushf "pushf")
  