Using Symbolic Execution and Data Flow Criteria to Aid Test Data Selection‖, software testing, verification and reliability

The utilization is described of a data Howpath selection criterion in a symbolic execution system. The system automaticaUy generates a subset of program paths according to a certain control How criterion. This subset is caUed the ZOT-subset, since it requires paths that traverse loops zero, one and two times. Experience indicates that traversing this subset of program paths is enough to cover most control Howand data Howcomponents of the program. The problem with the ZOT-subset is that it might contain, for large programs, a large number of paths. The number of paths in this subset can be reduced by concentrating on executable paths that cover vital components of programs such as data How components. This object is achieved by employing a data How path selection criterion in the system. The system symbolicaUyexecutes the paths of the ZOT-subset, and creates a system of branch conditions for each one. The user determines infeasible paths by checking the consistency of each system of conditions. The system selects feasible paths from the ZOT-subset that cover the data Howcriterion. Solving the systems of conditions of the selected paths provides the user with test data to fulfil the given data Howcriterion. KEY WORDS Software testing Symbolic execution Path selection Test data generation Data flow criteria Control flow criteria 1