Applying Code Refactoring and C Bounded Model Checker to Embedded Software

It is difficult for most embedded software to apply conventional testing techniques directly because of small memory and the limitation of user I/O. Typically software testing directly runs the software and checks the result and, in general, the software is linked with testing framework or related libraries to be executed. In this case the software can not run in embedded environment due to the increase of executable file and, even if run, it would be difficult to check the result because it is not common for the environment to be equipped with proper output device. Consequently, new technology is needed for embedded software to find out problems without directly executing the software. On the other hand, embedded software tends to be upgraded continuously but hardware is usually used without changing/modifying the configuration of initial design because of cost for redesign. To solve the problem, it is possible to reduce the size of executable file with low cost by applying code refactoring techniques before proceeding to hardware redesign. This paper suggests how to apply model checking tool, CBMC, to enhance software accuracy and to reduce the size of ever increasing embedded software using code refactoring.