An object oriented machine for control applications

Microprocessor design and manufacturing have experienced great improvements in the last years. However object-oriented concepts, in spite of their widespread diffusion as a programming principle, have not been given great attention in hardware design. This paper presents an object-oriented machine, currently under development, which incorporates (at the machine-code level) some mechanisms needed for manipulating objects and methods. The processor, oriented to control applications, is composed of a commercial, full-32-bit RISC processor acting as the computing core, and additional circuitry. The additional elements constitute a shell, providing dedicated registers and functions for dealing with class instances and related methods. A mechanism for tracking called methods, by hardware support of the Virtual Method Table, is provided in parallel to the normal calling operation of the processor. The overhead associated with this mechanism, normally taken in charge by the core processor, is therefore left to the additional circuitry