Verification of Transactional Memories that Support Non-Transactional Memory Accesses

A major challenge of Transactional memory implementations is dealing with memory accesses that occur outside of transactions. In previous work we showed how to specify transactional memory in terms of admissible interchanges of transaction operations, and gave proof rules for showing that an implementation satisfies its specification. However, we did not capture non-transactional memory accesses. In this work we show how to extend our previous model to handle non-transactional accesses. We apply our proof rules using a PVS-based theorem prover and produce a machine checkable, deductive proof for the correctness of implementations of transactional memory systems that handle non-transactional memory accesses.