A theoretical analysis of automatic inspection of the control flow of computer programs

Abstract

The authors have proposed an automated inspection on the control flow of computer programs, but its theoretical analysis has not been reported by other researchers yet. The automatic inspection on the control flow of a computer program is to check whether instructions are executed in intended order while executing the target program. The authors developed this automatic inspection by tracing the inconsistency between the execution of the target program and the general flowchart while using an interpreter to trace the flow. In this paper, after theoretically confirming each process of the automatic inspection algorithm, the following three points are discussed regarding the equivalence of the flow chart control flow and the program control flow. (1) The number of control flow paths in the flowchart is shown to be less than or equal to the number of program control flow paths when the program is coded correctly. (2) The necessary and sufficient condition for the input set selecting the control flow path of target-P which does not satisfy any control flow in GF to become empty set is that the macro statement becomes allocation statement for any input value, provided that the branches described in the flowchart are correctly coded. 3) we discuss the equivalence of the flow chart control flow and the program control flow.