text: /**
   * This is the C++ adaptation and derivative work of Myia (https://github.com/mila-iqia/myia/).
   *
   * Copyright 2019-2022 Huawei Technologies Co., Ltd
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   * http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  #ifndef MINDSPORE_CCSRC_FRONTEND_OPTIMIZER_CSE_H_
  #define MINDSPORE_CCSRC_FRONTEND_OPTIMIZER_CSE_H_
  
  #include <vector>
  #include <memory>
  #include "utils/hash_map.h"
  #include "ir/anf.h"
  #include "ir/manager.h"
  
  namespace mindspore {
  /* namespace to support opt */
  namespace opt {
  // Common subexpression elimination.
  class CSE {
   public:
    CSE() = default;
    virtual ~CSE() = default;
  
    virtual bool CheckReplace(const AnfNodePtr &main, const AnfNodePtr &node) const;
  
    virtual bool Cse(const FuncGraphPtr root, const FuncGraphManagerPtr manager) const;
  
    static bool HasHiddenSideEffect(const AnfNodePtr &node);
  
   protected:
    bool BuildOrderGroupAndDoReplaceForOneGraph(const FuncGraphPtr &fg, const FuncGraphManagerPtr &manager) const;
  
   private:
    bool BuildOrderGroupAndDoReplace(const FuncGraphManagerPtr manager) const;
    bool DoReplace(const FuncGraphManagerPtr manager, const std::vector<std::size_t> &order_group,
                   mindspore::HashMap<std::size_t, std::vector<AnfNodePtr>> *groups) const;
  };
  
  BasePtr AbsOf(const AnfNodePtr &node, bool ignore_fg_abs_tracking_id = false);
  }  // namespace opt
  }  // namespace mindspore
  
  #endif  // MINDSPORE_CCSRC_FRONTEND_OPTIMIZER_CSE_H_
  