Enhancement of CRD-based clone tracking

Many researchers have conducted a variety of research related to clone evolution. In order to grasp how clones have evolved, clones must be tracked. However, conventional clone tracking techniques are not feasible to track clones if they moved to another location in the source code. Consequently, in this research, we propose a new clone tracking technique. The proposed technique is an enhanced version of clone tracking with clone region descriptor (CRD) proposed by Duala-Ekoko and Robillard. The proposed technique can track clones even if they moved to another location. We have implemented a software tool based on the proposed technique, and applied it to two open source systems. In the experiment, we confirmed that the proposed technique could track 44 clone groups, which the conventional CRD tracking could not track. The accuracy of the tracking for those clones was 91%.