The implementation of object-oriented languages has been an active topic of research since the 1960s when the first Simula compiler was written. The topic received renewed interest in the early 1980s with the growing popularity of object-oriented programming languages such as c++ and Smalltalk, and got another boost with the advent of Java. Polymorphic calls are at the heart of object-oriented languages, and even the first implementation of Simula-67...