Fast and Flexible Large-Scale Clone Detection with CloneWorks

Clone detection in very-large inter-project repositories has numerous applications in software research and development. However, existing tools do not provide the flexibility researchers need to explore this emerging domain. We introduce CloneWorks, a fast and flexible clone detector for large-scale clone detection experiments. CloneWorks gives the user full control over the representation of the source code before clone detection, including easy plug-in of custom source transformation, normalization and filtering logic. The user can then perform targeted clone detection for any type or kind of clone of interest. CloneWorks uses our fast and scalable partitioned partial indexes approach, which can handle any input size on an average workstation using input partitioning. CloneWorks can detect Type-3 clones in an input as large as 250 million lines of code in just four hours on an average workstation, with good recall and precision as measured by our BigCloneBench.