anchor.diff:                                            (< (live-range-end range) index))
                                           active-ranges))
            (dolist (new-range (gethash index starts))
  +           (setf (gethash (live-range-vreg new-range) active-vreg-to-range-table) new-range)
              (push new-range active-ranges))
            (loop
               for (variable vreg repr) in (gethash inst original-debug-map)
  -            for range = (find vreg active-ranges :key #'live-range-vreg) ; might be worth maintaining this as a hash-table.
  +            for range = (gethash vreg active-vreg-to-range-table)
               for location = (if (interval-spilled-p allocator range)
                                  vreg
                                  (gethash range range-allocations))
  
positive.code:        for i from 0
         for inst in (allocator-instruction-ordering allocator)
         do (format t "~D: " i) (ir::print-instruction inst)))
    (let ((result (make-hash-table))
          (spilled-ranges (sort (all-spilled-ranges allocator)
                                #'<
                                :key #'live-range-start))
  
negative.code:              (setf (gethash current-vreg result) '()))
             ;; Add new interference edges.
             (dolist (range live)
               (when (not (eq (live-range-vreg range) current-vreg))
                 (pushnew current-vreg (gethash (live-range-vreg range) result) :test 'eq)
                 (pushnew (live-range-vreg range) (gethash current-vreg result) :test 'eq)))
             (push range live)))
      result))
  
  