On the control structure of a program slice

We present a linear-time algorithm that yields the control structure of a program slice, even if the program being sliced is unstructured. From the flow graph of a program, the nodes and arcs that do not belong to a given slice are systematically deleted, so that the resulting flow graph contains only the predicates and statements of the slice and preserves the meaning of the original program with respect to the predicates and statements of the given slice.