class SplitCloneHelper :  public dvm::CloneHelper {
  IntArrayRef *GetClone(IntArrayRef *shape) override {
    auto it = ref_map_.find(shape);
    return it != ref_map_.end() ? static_cast<IntArrayRef *>(it->second) : shape;
  }
  ScalarRef *GetClone(ScalarRef *scalar) override {
    auto it = ref_map_.find(scalar);
    return it != ref_map_.end() ? static_cast<ScalarRef *>(it->second) : scalar;
  }
  NDObject *GetClone(NDObject *op) override {
    auto it = op_map_.find(op);
    return it != op_map_.end() ? it->second : nullptr;
  }
  void SetClone(NDObject *op, NDObject *clone) override {
    op_map_[op] = clone;
  }
  std::unordered_map<NDObject *, NDObject *> op_map_;
  std::unordered_map<void *, void *> ref_map_;
};

class ExeGraphSplitKernelPy ： public GraphSplitKernelPy {
 std::mutex executor_mutex_;
 std::vector<GraphSplitKernelPy *> executors_;
 
  void Setup() override {
    SetupRelocs();
    kernel_.Infer(); 
    executors_->push_back(this);    //当前节点作为第一个执行实例
  }
 
  GraphSplitKernelPy *Clone() {   // 基于当前节点clone其它执行实例
    SplitCloneHelper helper;
    auto kernel = new GraphSplitKernelPy();
    for (auto ref : shapes_) {
      helper[ref] = new ShapeWithRef(ref->size);
    }
    kernel->Clone(this, helper);
    for (auto load: loads_) {
      kernel->loads_.push_back(helper.GetClone(load));
    }
    for (auto store: stores_) {
      kernel->stores_.push_back(helper.GetClone(store));
    }
    kernel->contiguity_flags_ = contiguity_flags_;
    kernel->Setup();
    return kernel;
  }

  py::object Call(py::args inputs) override {
   GraphSplitKernelPy *executor = nullptr;
   {
     std::lock_guard<executor_mutex_> lock;
     if (!executors_.empty()) {
       executor = executors_.back();
       executors_.pop_back();
     }
   }
   if (executor == nullptr) {
     executor = Clone();
   }
   ...
   auto launch_call = [executor]() {
     executor->GraphSplitBase::Launch(...);
     {
       std::lock_guard<executor_mutex_> lock;
       executors_.push_back(executor);
     }
   };
   RunOpApiV2(op_name_, launch_call);
  }
};