Abstract: Processor extensions and software verification to support type-safe language environments running with untrusted code. Code and data spaces are partitioned into trusted and untrusted regions. Type-safe code is loaded into the trusted region of the code space, while non-type-safe code is loaded into the untrusted region of the code space. The trusted region of the data space is allocated to the type-safe code. The untrusted region of the data space is allocated to the non-type-safe code. Hardware-based truth tables are employed for defining allowable and disallowable code sequences and memory access operations. For code sequences, allowable operations are based on the location (i.e., region) of a code sequence including a current instruction and a prior instruction. For memory access, the location of the requesting instruction and data requested are considered. Disallowed code sequence or memory access operations cause the processor to generate a safe access protection trap.

Abstract: Processor extensions and software verification to support type-safe language environments running with untrusted code. Code and data spaces are partitioned into trusted and untrusted regions. Type-safe code is loaded into the trusted region of the code space, while non-type-safe code is loaded into the untrusted region of the code space. The trusted region of the data space is allocated to the type-safe code. The untrusted region of the data space is allocated to the non-type-safe code. Hardware-based truth tables are employed for defining allowable and disallowable code sequences and memory access operations. For code sequences, allowable operations are based on the location (i.e., region) of a code sequence including a current instruction and a prior instruction. For memory access, the location of the requesting instruction and data requested are considered. Disallowed code sequence or memory access operations cause the processor to generate a safe access protection trap.

Abstract: A method is provided including determining if an object has been published previously, identifying the object as public according to whether the object has been published previously, identifying objects reachable from the object as public according to whether the object has been published previously, and publishing the object. An apparatus for performing the method, and an article including a machine- accessible medium that provides instructions that, if executed by a processor, will cause the processor to perform the method are also provided.