  Proving the correctness of programs written for multiple processors is a
challenging problem, due in no small part to the weaker memory guarantees
afforded by most modern architectures. In particular, the existence of store
buffers means that the programmer can no longer assume that writes to different
locations become visible to all processors in the same order. However, all
practical architectures do provide a collection of weaker guarantees about
memory consistency across processors, which enable the programmer to write
provably correct programs in spite of a lack of full sequential consistency. In
this work, we present a mechanization in the ACL2 theorem prover of an
axiomatic weak memory model (introduced by Alglave et al.). In the process, we
provide a new proof of an established theorem involving these axioms.
