ISL - AN INTERVAL LOGIC FOR THE SPECIFICATION OF REAL-TIME PROGRAMS

ISL is a linear-time temporal logic for specifying properties of programs in execution intervals which are sequences of states. The end points of intervals are specified using instances of state predicates (or assertions) or time values. Abstract intervals, delimited by formulae over states in a computation, are used as the first step in constructing a timed specification. This is then transformed to incorporate timing, first by logical formulae and then using concrete time domains. Refinements are introduced to define time domains and timing properties and include refinement to programming constructs. We outline a way to specify resource limitations along with the functional and timing properties of programs. The specification method is illustrated with some examples.