A cross platform system emulator is a hyper-visor which can emulate a source ISA (Instruction Set Architecture) platform on a different target ISA platform. Since the source instruction cannot be executed directly on the target system, each CPU instruction of the source platform should be converted to one or more target instructions. This incurs additional overhead, thus reducing the overall performance. In this paper we propose a solution to improve the performance of cross platform emulators that use a binary translator to translate a guest ISA to a target ISA. The solution para-virtualizes hot guest functions by invoking a more efficient host native code instead of translated guest code
