|
Liveness |
|
Liveness Problems
We only give a short introduction to the notions of liveness problems in the context
of top rewrite systems. For a more detailed introduction we refer to
[GZ '03].
For a top symbol top a term t is called a top term if and only
if t = top(t1, ..., tn) and all t1, ..., tn
do not contain top.
A term rewrite system over the signature Σ ∪ {top} is
a top rewrite system if all rules are either of the form
- s → t where s and t are top terms or
- s → t where s and t do not contain top.
Liveness Property
The transformation techniques in AProVE can handle eventuality
liveness problems where we start from top terms and wish to
determine if we eventually reach a state (term) from the set G
of good states (terms).
The set of good states G here is defined as the set of all
states (terms) which do not contain any instances of a
given term as a subterm.
For two examples of such liveness properties see Subsection 5.3
of [GZ '03].