anchor.diff:                         `(sys.lap-x86:mov64 :r13 (:symbol-function :r13))
                          function-label
                          `(sys.lap-x86:call :r13)
  -                       `(sys.lap-x86:mov64 :lsp :rbx)))
  +                       `(sys.lap-x86:mov64 :lsp ,(control-stack-slot-ea stack-pointer-save-area))))
                  (setf *r8-value* (list (gensym))))))
             (t (cg-function-form `(error '"TODO multiple-value-call with >1 arguments."))))))
   
  
positive.code:                (when (not value-tag)
                   (return-from cg-multiple-value-call nil))
                 (load-multiple-values value-tag)
                 (load-in-reg :r13 fn-tag t)
                 (let ((type-error-label (gensym))
                       (function-label (gensym)))
  
negative.code:            (cg-function-form `(funcall ,function)))
            ((null (cdr value-forms))
             ;; Single value form.
             (let ((fn-tag (let ((*for-value* t)) (cg-form function)))
                   (stack-pointer-save-area (allocate-control-stack-slots 1)))
               (when (not fn-tag)
                 (return-from cg-multiple-value-call nil))
               (let ((value-tag (let ((*for-value* :multiple))
  