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arXiv · 1804.06612

On the Completeness of Verifying Message Passing Programs under Bounded Asynchrony

Ahmed Bouajjani·Constantin Enea·Kailiang Ji·Shaz Qadeer
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Abstract

We address the problem of verifying message passing programs, defined as a set of parallel processes communicating through unbounded FIFO buffers. We introduce a bounded analysis that explores a special type of computations, called k-synchronous. These computations can be viewed as (unbounded) sequences of interaction phases, each phase allowing at most k send actions (by different processes), followed by a sequence of receives corresponding to sends in the same phase. We give a procedure for deciding k-synchronizability of a program, i.e., whether every computation is equivalent (has the same happens-before relation) to one of its k-synchronous computations. We also show that reachability over k-synchronous computations and checking k-synchronizability are both PSPACE-complete. Furthermore, we introduce a class of programs called {\em flow-bounded} for which the problem of deciding whether there exists a k>0 for which the program is k-synchronizable, is decidable.

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Ahmed Bouajjani, Constantin Enea, Kailiang Ji, Shaz Qadeer. 2018-04-18. On the Completeness of Verifying Message Passing Programs under Bounded Asynchrony. https://arxiv.org/abs/1804.06612

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