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We present the explicit state model checker HSF-SPIN which is based on the model checker SPIN and its Promela modeling language. HSF-SPIN incorporates directed search algorithms for checking safety and a large class of LTL-specified liveness properties. We start off from the A* algorithm and define heuristics to accelerate the search into the direction of a(More)
Message Sequence Charts (MSCs) are increasingly used in software engineering methodologies and tools to capture, for instance, system requirements, test scenarios, and simulation traces. They have been standardized by ITU-T in Recommendation Z.120 IT96]. However, various aspects of environment behavior remain underspeciied in MSCs, e.g., the presence of(More)
We present a method to enhance fault localization for software systems based on a frequent pattern mining algorithm. Our method is based on a large set of test cases for a given set of programs in which faults can be detected. The test executions are recorded as function call trees. Based on test oracles the tests can be classified into successful and(More)
The success of model checking is largely based on its ability to efficiently locate errors in software designs. If an error is found, a model checker produces a trail that shows how the error state can be reached, which greatly facilitates debugging. However, while current model checkers find error states efficiently, the counterexamples are often(More)
Current stochastic model checkers do not make counterexamples for property violations readily available. In this paper, we apply directed explicit state-space search to discrete and continuous-time Markov chains in order to compute counterexamples for the violation of PCTL or CSL properties. Directed explicit state-space search algorithms explore the state(More)
We give a semantics for Message Flow Graphs (MFGs), which play the role for interprocess communication that Program Dependence Graphs play for control flow in parallel processes. MFGs have been used to analyse parallel code, and are closely related to Message Sequence Charts and Time Sequence Diagrams in telecommunications systems. Our requirements are(More)
We present a directed search algorithm, called K∗, for finding the k shortest paths between a designated pair of vertices in a given directed weighted graph. K∗ has two advantages compared to current k-shortest-paths algorithms. First, K∗ operates on-the-fly, which means that it does not require the graph to be explicitly available and stored in main(More)