unique_scope_id_(0) {}

  Status Run();

 private:
  Status ScopingForPipelineStages();

  size_t GetUniqueScopeId() { return unique_scope_id_++; }

  void AddScopeToAllTransitivePredecessors(Node* start);

  void AddScopeToAllTransitiveSuccessors(Node* start);

 private:
  Graph* graph_;
  OptimizerOptions::GlobalJitLevel global_jit_level_;
  size_t unique_scope_id_;
};