A method and system for supporting simultaneous operation of operating systems on a single integrated circuit. The system includes a supervisory operating system (SOS) managing execution of instructions, each instruction being executable under one of the operating systems; registers grouped into multiple sets of registers, each set maintaining an identity of one of the operating systems; and a dispatcher capable of dispatching an instruction and a tag attached to the instruction, the tag identifying one of the operating systems and the instruction to be executed under the identified operating system to access one of the registers. One or more of the registers are utilized when the instruction is executed, and are included in a single set of the multiple sets of registers. The single set maintains the identity of the operating system identified by the tag, and each of the one or more registers includes an identifier matching the tag.