摘要:
A system and method for conducting symbolic partial order reduction for concurrent systems includes determining a guarded independence relation which includes transitions from different threads that are independent for a set of states, when a condition or predicate holds. Partial order reduction is performed using the guarded independence relation to permit automatic pruning of redundant thread interleavings when the guarded independence condition holds.
摘要:
Systems and method provide a coverage-guided systematic testing framework by dynamically learning HaPSet ordering constraints over shared object accesses; and applying the learned HaPSet ordering constraints to select high-risk interleavings for future test execution.
摘要:
A static, inter-procedural dataflow analysis is used to debug multi-threaded programs which heretofore have been thought unsuitable for concurrent multi-threaded analysis.
摘要:
A system and method for discovering a set of possible iteration sequences for a given loop in a software program is described, to transform the loop representation. In a program containing a loop, the loop is partitioned into a plurality of portions based on splitting criteria. Labels are associated with the portions, and an initial loop automaton is constructed that represents the loop iterations as a regular language over the labels corresponding to the portions in the program. Subsequences of the labels are analyzed to determine infeasibility of the subsequences permitted in the automaton. The automaton is refined by removing all infeasible subsequences to discover a set of possible iteration sequences in the loop. The resulting loop automaton is used in a subsequent program verification or analysis technique to find violations of correctness properties in programs.
摘要:
A system and method for race warning generation for computer program verification includes determining shared variables and determining context-sensitive points-to sets for lock pointers by focusing on pointers that may affect aliases of lock pointers, and by leveraging function summarization. Locksets are determined at locations where shared variables are accessed using the points-to sets for lock pointers. Warnings are based on disjointness of locksets.
摘要:
The Complete-1-Distinguishability (C-1-D) property is used for simplifying FSM verification. This property eliminates the need for a traversal of the product machine for the implementation machine and the specification machine. Instead, a much simpler check suffices. This check consists of first obtaining a 1-equivalence mapping between the states of the two machines, and then checking that it is a bisimulation relation. The C-1-D property can be used directly on specifications for which it naturally holds. This property can be enforced on arbitrary FSMs by exposing some of the latch outputs as pseudo-primary outputs during synthesis and verification. In this sense, the synthesis/verification methodology provides another point in the tradeoff curve between constraints-on-synthesis versus complexity-of-verification.
摘要:
A system and method for program verification includes generating a product transaction graph for a concurrent program, which captures warnings for potential errors. The warnings are filtered to remove bogus warnings, by using constraints from synchronization primitives and invariants that are derived by performing one or more dataflow analysis methods for concurrent programs. The dataflow analysis methods are applied in order of overhead expense. Concrete execution traces are generated for remaining warnings using model checking.
摘要:
A system and method for race warning generation for computer program verification includes determining shared variables and determining context-sensitive points-to sets for lock pointers by focusing on pointers that may affect aliases of lock pointers, and by leveraging function summarization. Locksets are determined at locations where shared variables are accessed using the points-to sets for lock pointers. Warnings are based on disjointness of locksets.
摘要:
A system and method for dynamic data race detection for concurrent systems includes computing lockset information using a processor for different components of a concurrent system. A controlled execution of the system is performed where the controlled execution explores different interleavings of the concurrent components. The lockset information is used during the controlled execution to check whether a search subspace associated with a state in the execution is free of data races. A race-free search subspace is dynamically pruned to reduce resource usage.
摘要:
A system and method for analyzing concurrent programs that guarantees optimality in the number of thread inter-leavings to be explored. Optimality is ensured by globally constraining the inter-leavings of the local operations of its threads so that only quasi-monotonic sequences of threads operations are explored. For efficiency, a SAT/SMT solver is used to explore the quasi-monotonic computations of the given concurrent program. Constraints are added dynamically during exploration of the concurrent program via a SAT/SMT solver to ensure quasi-montonicity for model checking.