A formal approach to three-way merging of EMF models

Inadequate version control for models significantly impedes the application of model-driven software development. In particular, sophisticated support for merging model versions is urgently needed. In this paper, we present a formal approach to three-way merging of models in the EMF framework which may be applied to instances of arbitrary Ecore models. We specify context-free and context-sensitive rules for model merging which both detect and resolve merge conflicts. Furthermore, we present a merge algorithm which produces a valid model provided it is supplied with valid input models.