27 Apr 2019
•
Akshay S.
•
Gastin Paul
•
Juge Vincent
•
Krishna Shankara Narayanan
In this paper, we analyze timed systems with data structures, using a rich
interplay of logic and properties of graphs. We start by describing behaviors
of timed systems using graphs with timing constraints...Such a graph is called
realizable if we can assign time-stamps to nodes or events so that they are
consistent with the timing constraints. The logical definability of several
graph properties has been a challenging problem, and we show, using a highly
non-trivial argument, that the realizability property for collections of graphs
with strict timing constraints is logically definable in a class of
propositional dynamic logic (EQ-ICPDL), which is strictly contained in MSO. Using this result, we propose a novel, algorithmically efficient and uniform
proof technique for the analysis of timed systems enriched with auxiliary data
structures, like stacks and queues. Our technique unravels new results (for
emptiness checking as well as model checking) for timed systems with richer
features than considered so far, while also recovering existing results.(read more)