Abstract: Persistent data storage for client computer software programs is provided using a repository that enables client computer software programs to store data securely on a client computer system, subsequently retrieve that data, and optionally share the data in a controlled fashion with authorized client computer software programs. The present invention can be used by both trusted and untrusted client computer software programs that either reside locally on the client computer system or are downloaded from a server computer system. A benefit of the present invention is that it allows untrusted applets to have access to persistent storage without compromising the integrity of the client computer system. Since the present invention controls persistent storage space, not the programmer of the client computer software program, the burden of insuring storage integrity and security is removed from the programmer.

Abstract: A method and apparatus is disclosed for control of a central processor in response to a branch instruction using two separate, subsequently updated condition codes. Computer architecture is provided wherein the condition codes which determine the processor state result from the execution of instructions prior to the currently executing instruction. When the preceding instructions are executed, condition codes are set and maintained in a first condition code register. The first condition code is transferred to the second condition code register, and the first condition code register is updated to reflect the result of the current instruction execution. Any condition code state such as a branch used by the third instruction is based on the condition code state maintained in the second condition code register.