anchor.diff:      (setf (aref *stack-values* rest-head) nil
             (aref *stack-values* rest-tail) nil)))
   
  +(defun flush-data-registers (multiple-values)
  +  ;; Flush out any possible references to dynamic-extent values.
  +  ;; If multiple-values is true, then obey the multiple-values protocol
  +  ;; to limit which registers are cleared, otherwise get all but R8.
  +  (emit `(sys.lap-x86:xor32 :ebx :ebx)
  +        `(sys.lap-x86:xor32 :r13d :r13d))
  +  (if multiple-values
  +      (emit `(sys.lap-x86:cmp32 :ecx ,(fixnum-to-raw 2))
  +            `(sys.lap-x86:cmov32ae :r9d :ebx)
  +            `(sys.lap-x86:cmp32 :ecx ,(fixnum-to-raw 3))
  +            `(sys.lap-x86:cmov32ae :r10d :ebx)
  +            `(sys.lap-x86:cmp32 :ecx ,(fixnum-to-raw 4))
  +            `(sys.lap-x86:cmov32ae :r11d :ebx)
  +            `(sys.lap-x86:cmp32 :ecx ,(fixnum-to-raw 5))
  +            `(sys.lap-x86:cmov32ae :r12d :ebx))
  +      (emit `(sys.lap-x86:xor32 :r9d :r9d)
  +            `(sys.lap-x86:xor32 :r10d :r10d)
  +            `(sys.lap-x86:xor32 :r11d :r11d)
  +            `(sys.lap-x86:xor32 :r12d :r12d))))
  +
   (defun cg-form (form)
     (flet ((save-tag (tag)
   	   (when (and tag *for-value* (not (keywordp tag)))
  
positive.code:         (emit-rest-list lambda arg-registers)))
      ;; No longer in argument setup mode, switch over to normal GC info.
      (emit-gc-info)
      (let* ((code-tag (let ((*for-value* (if *perform-tce* :tail :multiple)))
                         (cg-form `(progn ,@(lambda-information-body lambda))))))
        (when code-tag
          (unless (eql code-tag :multiple)
            (load-in-r8 code-tag t)
            (emit `(sys.lap-x86:mov32 :ecx ,(fixnum-to-raw 1))))
          (emit `(sys.lap-x86:leave)
                `(:gc :no-frame)
                `(sys.lap-x86:ret))))
  
negative.code:          (*code-accum* '())
           (*trailers* '())
           (arg-registers '(:r8 :r9 :r10 :r11 :r12))
           (*gc-info-fixups* '())
           (*used-dynamic-extent* nil))
      ;; Check some assertions.
      ;; No keyword arguments, no special arguments, no non-constant
      ;; &optional init-forms and no non-local arguments.
  