BIDIRECTIONAL OBJECT LAYOUT FOR SEPARATE COMPILATION

Existing schemes for object layout and dispatch in the presence of mul tiple inheritance and separate compilation waste space and are slower than systems with single inheritance. This paper describes the bidirec tional object layout, a new scheme for object layout that produces sma ller objects and faster method invocations than existing schemes by au tomatically optimizing particular uses of multiple inheritance. The bi directional object layout is used for the programming language Theta, and is applicable to languages like C++. This paper also demonstrates how to efficiently implement method dispatch when method signatures ar e allowed to change in subclasses. Most current statically compiled la nguages require identical signatures for efficiency.