Section: New Software and Platforms

FuncTion : An Abstract Domain Functor for Termination

Participants : Caterina Urban, Antoine Miné [Correspondent] .

FuncTion is a research prototype static analyzer to analyze the termination and functional liveness properties of programs. It accepts programs in a small non-deterministic imperative language. It is also parameterized by a property: either termination, or a recurrence or a guarantee property (according to the classification by Manna and Pnueli of program properties). It then performs a backward static analysis that automatically infers sufficient conditions at the beginning of the program so that all executions satisfying the conditions also satisfy the property. FuncTion is based on an extension to liveness properties of the framework to analyze termination by abstract interpretation proposed by Patrick Cousot and Radhia Cousot in [39] . FuncTion infers ranking functions using piecewise-defined abstract domains. Several domains are available to partition the ranking function, including intervals, octagons, and polyhedra. Two domains are also available to represent the value of ranking functions: a domain of affine ranking functions, and a domain of ordinal-valued ranking functions (which allows handling programs with unbounded non-determinism).

The analyzer is written in OCaml and implemented on top of the Apron library. It can be used on-line through a web interface: http://www.di.ens.fr/~urban/FuncTion.html .

FuncTion participated to SV-COMP 2014 (3rd Competition on Software Verification, demonstration section) and is also selected to participate to SV-COMP 2015 in the termination category [31] .