International Business Machines Corporation

Dmitry Pidan

Allon Adir

Tamer Salman

Fady Copty

Sitvanit Ruah

Hana Chockler

Oded Margalit

Karen Frida Yorav

Tatyana Veksler

Method, apparatus and product for symbolic execution of alternative branches. The method comprising reaching, during symbolic execution of a Control Flow Graph (CFG) of a program, a branching node in the CFG with a first symbolic state, wherein the branching has at least a first branch and a second branch, wherein the first and second branches end at a joining node in the CFG. The method further comprises symbolically executing the first branch using the first symbolic state so as to determine a second symbolic state. The method further comprises symbolically executing the second branch using the second symbolic state so as to determine a third symbolic state. Accordingly, the third symbolic state is based on sequential symbolic execution of alternative branches.

Symbolic execution of alternative branches

According to one exemplary embodiment, a method for preparing a software component for verification is provided. The method may include receiving the software component and a design model. The method may also include generating a wrapper program based on the received software component and the received design model. The method may then include associating the received software component with the generated wrapper program. The method may further include determining a plurality of inputs for the received software component based on the received design model. The method may also include sending the determined plurality of inputs and the received software component with associated wrapper program to a verification tool.

Unit-level formal verification for vehicular software systems

A method, system and product for directing verification towards bug-prone portions. The method comprising syntactically analyzing a computer program to identify portions of the computer program that correspond to one or more bug patterns; and performing verification of the computer program, wherein the verification comprises traversing a control flow graph of the computer program and tracking symbolic values of variables of the computer program, wherein said performing comprises directing the traversal of the control flow graph to nodes of the control flow graph that correspond to the identified portions, whereby bug-prone portions of the computer program are prioritized to be verified before non-bug-prone portions of the computer program.

Directing verification towards bug-prone portions

A method, apparatus and product for dominant state based coverage metric. The method comprising: determining whether all possible states of a computer program were examined based on an analysis of states that were examined excluding controlled states that are dominated by a self-dominating states; wherein the controlled states are associated with a controlled nodes in a control flow graph of the computer program, wherein the self-dominating states are associated with a self-dominating node in the control flow graph; wherein each execution path in the control flow graph that reaches the controlled nodes also includes the self-dominating node; and wherein there exists an execution path in the control flow graph that both starts and ends at the self-dominating node and further includes at least one controlled node.

Dominant-state-based coverage metric

A computer-implemented method for verifying a design includes representing a verification directive, which pertains to the design and includes a local variable, by a finite state machine. The state machine includes multiple states, with transitions among the states, transition conditions associated with the transitions, and procedural blocks, which correspond to the transitions and define operations to be performed on the local variable when traversing the respective transitions. The finite state machine is executed by traversing the transitions in accordance with the respective transition conditions and modifying the local variable in accordance with the respective procedural blocks of the traversed transitions, so as to verify the design with respect to the verification directive.

Growing community of inventors

Netanya, Israel

Dmitry Pidan