Bounded model checking is among the most efficient techniques for the automated verification of concurrent programs. However, due to the nondeterministic thread interleavings, a large and complex formula is usually required to give an exact encoding of all possible behaviors, which significantly limits the scalability. Observing that the large formula is usually dominated by the exact encoding of the scheduling constraint, this paper proposes a novel scheduling constraint based abstraction refinement method for multi-threaded C program verification. Our method is both efficient in practice and complete in theory, which is challenging for existing techniques. To achieve this, we first proposed an effective and powerful technique which works well for nearly all benchmarks we evaluated. We have proposed the notion of Event Order Graph (EOG), and have devised two graph-based algorithms over EOG for counterexample validation and refinement generation, which can often obtain a small yet effective refinement constraint. Then, to ensure completeness, our method was enhanced with two constraint-based algorithms for counterexample validation and refinement generation. Experimental results on SV-COMP 2017 benchmarks and two real-world server systems indicate that our method is promising and significantly outperforms the state-of-the-art tools.

中文翻译：

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用于多线程程序验证的调度约束抽象

有界模型检查是自动验证并发程序的最有效技术之一。然而，由于线程交织的不确定性，通常需要一个大而复杂的公式来给出所有可能行为的精确编码，这显着限制了可扩展性。观察到大公式通常由调度约束的精确编码决定，本文提出了一种新的基于调度约束的抽象细化方法，用于多线程C程序验证。我们的方法在实践中既有效又理论上完整，这对现有技术具有挑战性。为了实现这一目标，我们首先提出了一种有效且强大的技术，该技术几乎适用于我们评估的所有基准。我们提出了事件顺序图（EOG）的概念，并在 EOG 上设计了两种基于图的算法，用于反例验证和细化生成，这通常可以获得一个小而有效的细化约束。然后，为了确保完整性，我们的方法通过两种基于约束的算法进行了增强，用于反例验证和细化生成。SV-COMP 2017 基准测试和两个真实世界服务器系统的实验结果表明，我们的方法很有前途，并且明显优于最先进的工具。