Memorax, a Precise and Sound Tool for Automatic Fence Insertion under TSO

We introduce Memorax, a tool for the verification of control state reachability (i.e., safety properties) of concurrent programs manipulating finite range and integer variables and running on top of weak memory models. The verification task is non-trivial as it involves exploring state spaces of arbitrary or even infinite sizes. Even for programs that only manipulate finite range variables, the sizes of the store buffers could grow unboundedly, and hence the state spaces that need to be explored could be of infinite size. In addition, Memorax incorporates an interpolation based CEGAR loop to make possible the verification of control state reachability for concurrent programs involving integer variables. The reachability procedure is used to automatically compute possible memory fence placements that guarantee the unreachability of bad control states under TSO. In fact, for programs only involving finite range variables and running on TSO, the fence insertion functionality is complete, i.e., it will find all minimal sets of memory fence placements (minimal in the sense that removing any fence would result in the reachability of the bad control states). This makes Memorax the first freely available, open source, push-button verification and fence insertion tool for programs running under TSO with integer variables.

[1]  Eran Yahav,et al.  Automatic inference of memory fences , 2010, Formal Methods in Computer Aided Design.

[2]  Parosh Aziz Abdulla,et al.  Counter-Example Guided Fence Insertion under TSO , 2012, TACAS.

[3]  Rajeev Alur,et al.  A Temporal Logic of Nested Calls and Returns , 2004, TACAS.

[4]  Thuan Quang Huynh,et al.  A Memory Model Sensitive Checker for C# , 2006, FM.

[5]  Pierre Wolper,et al.  A Verification-Based Approach to Memory Fence Insertion in Relaxed Memory Systems , 2011, SPIN.

[6]  Dennis Shasha,et al.  Efficient and correct execution of parallel programs that share memory , 1988, TOPL.

[7]  Scott Owens,et al.  Reasoning about the Implementation of Concurrency Abstractions on x86-TSO , 2010, ECOOP.

[8]  Eran Yahav,et al.  Partial-coherence abstractions for relaxed memory models , 2011, PLDI '11.

[9]  Pierre Wolper,et al.  An Automata-Based Symbolic Approach for Verifying Programs on Relaxed Memory Models , 2010, SPIN.

[10]  Sarita V. Adve,et al.  Shared Memory Consistency Models: A Tutorial , 1996, Computer.

[11]  Parosh Aziz Abdulla,et al.  Automatic Fence Insertion in Integer Programs via Predicate Abstraction , 2012, SAS.

[12]  Andreas Podelski,et al.  ACSAR: Software Model Checking with Transfinite Refinement , 2007, SPIN.

[13]  Theo D'Hondt.  ECOOP 2010 - Object-Oriented Programming, 24th European Conference, Maribor, Slovenia, June 21-25, 2010. Proceedings , 2010, ECOOP.

[14]  Tobias Nipkow,et al.  FM 2006: Formal Methods, 14th International Symposium on Formal Methods, Hamilton, Canada, August 21-27, 2006, Proceedings , 2006, FM.

[15]  Sebastian Burckhardt,et al.  CheckFence: checking consistency of concurrent data types on relaxed memory models , 2007, PLDI '07.