invalidate(im);
if (im != null) { invalidate(im); }
  private void handleSubclassing (VM_Class c) {    VM_Class sc = c.getSuperClass();    if (sc == null)      return;                   // c == java.lang.Object.    java.util.Iterator invalidatedMethods = db.invalidatedBySubclass(sc);    if (invalidatedMethods != null) {      while (invalidatedMethods.hasNext()) {        int cmid = ((Integer)invalidatedMethods.next()).intValue();        VM_CompiledMethod im = VM_CompiledMethods.getCompiledMethod(cmid);        invalidate(im);      }      db.removeNoSubclassDependency(sc);    }  }