Abstract: Software testing is the most important topic of producing software today.In this article，a method of statement block is used to accomplish the procedure from source program to dominated flow graph.Automata machine and loop edge is introduced to perform the change between them.The improved method can obtain the number of path coverage and information in detail，reduce the number of generated paths，perform easy，and satisfy the goal.

Key words: dominated flow graph, path coverage testing, statement block, automata machine

摘要： 软件测试是当前软件生成重要的研究课题。文中从源程序开始，引入基本块的方法将源程序转换为相应的控制流程图。并采用图形的方法将路径构造相应的自动机，通过对自动机中回边的处理，生成简化的并与之等价的自动机。经过若干变换后，可在自动机上直观地求出路径覆盖的条数和相应的信息。此方法实现路径覆盖的目标，简化路径覆盖生成过程，步骤直观，且减少路径生成数。

关键词: 控制流程图, 覆盖测试, 基本块, 自动机