After special cut was generated by tracing from a special pair of CEP, dependencies among high level nodes in special cut were removed for optimization, and the equivalence for the special pair of CEP was verified by using special cut.

• 从特定候选等价点进行回溯得到专用割集，通过消除高层次结点间的依赖关系对专用割集进行优化，用专用割集验证特定候选等价点的等价性。