An industry of IP reuse has developed and is maturing in order to relieve the pressure of escalating design complexity in diminished development time. Electronic system engineers are offered ready-made or customizable functional cores which may be added to designs. This paper will survey and discuss a subset of currently available microprocessor cores, focussing on 32-bit RISC processors. It will introduce a bytecode folding algorithm and a project to implement a combination of that algorithm and a RISC core to create a processor capable of executing both RISC and Java instructions natively. Conclusions will be drawn about which of the surveyed cores is most suitable for this project.