Linkage mechanism for program isolation

Abstract From the Canadian patent

Abstract Of The Disclosure, A computer system has general purpose registers control registers and access registers for containing information to allow address space capability. A linkage stack uses protected address space to store state information during program call and program return operations. The linkage stack contains information relating to state entries for the saved information and header and trailer entries to point to other linkage stack sections. A control register contains the pointer to the current linkage stack entry and is changed as the program call or return moves through the stack.