State coverage of embedded realtime programs

Abstract

Overall functional coverage is the ratio of states actually tested to all states derived from the value domains of the data, using the concept of equivalence classes to reduce the number of possible states. At least three levels of state coverage result: (1) generation of each input state triggering a specified action: (2) generation of each input state specified by the human oracle; and (3) generation of each possible input state. Functional coverage based on the specification is therefore proposed as an alternative to structural and data coverage. However, to make functional coverage measurable, it is necessary to define input states based on a prediction of the usage profile. One way of doing this is to use a special assertion language that pairs preconditions and postconditions together with operational modes and time constraints. Generating all specified preconditions and validating all specified postconditions for all operational modes under all time constraints is equivalent to functional coverage, provided that all relevant input states are covered by the specification.<>