EMULATION COPROCESSOR

A computer system employing a host processor and an emulation coprocessor. The host processor includes hardware configured to execute instructions defined by a host instruction set architecture, while the emulation coprocessor includes hardware configured to execute instructions defined by a different instruction set architecture from the host instruction set architecture (“the foreign instruction set architecture”). The host processor core executes operating system code as well as application programs which are coded in the host instruction set architecture. Upon initiation of a foreign application program, the host processor core communicates with the emulation coprocessor core to cause the emulation coprocessor core to execute the foreign application program. Accordingly, application programs coded according to the foreign instruction set architecture can be executed directly in hardware. The computer system may be characterized as a heterogeneous multiprocessing system. While the emulation coprocessor is executing the foreign application program, the host processor may execute operating system routines unrelated to the foreign application program or may execute a host application program.