@Override
  public void visitReferenceExpression(@NotNull GrReferenceExpression ref) {
    super.visitReferenceExpression(ref);
    PsiElement resolved = ref.resolve();
    if (!allVars.containsKey(resolved)) {
      return;
    }
    GrVariable var = (GrVariable)resolved;

    if (PsiUtil.isAccessedForWriting(ref)) {
      rewritten.add(var);
    }

    if (allVars.getInt(var) < grade) {
      touched.add((PsiVariable)resolved);
    }
  }
@Override
  public void visitReferenceExpression(@NotNull GrReferenceExpression ref)