Completeness of ASM Refinement
G. Schellhorn
ASM refinements are verified using generalized
forward simulations which allow to refine m abstract operations
to n concrete operations with arbitrary m and n. One main difference
to data refinement is that ASM refinement considers infinite runs and termination.
Since backward simulation does not preserve termination in general,
the standard technique of adding history information to the concrete
level is not applicable. The powerset construction also adds infinite
runs and is therefore not applicable too. This paper shows that a completeness
proof is nevertheless possible by adding infinite prophecy information, effectively
moving nondetermism to the initial state. Adding such prophecy information
can be done on the semantic level, but also by a simple syntactic
transformation that removes the choose construct of ASMs.
The completeness proof is also ported to give a completeness proof for IO automata.
erschienen 2008
Electronic Notes in Theoretical Computer Science (ENTCS) Vol 214, p. 25-49, 2008
