METHOD AND APPARATUS FOR EVALUATING AND DEBUGGING ASSERTIONS

Roughly described, assertion expressions are evaluated against the binary signal values of a circuit simulation in such a way as to be able to report status information at intermediate levels of assertion subexpressions. In one embodiment, the status information reported for an intermediate subexpressions contains the final status of that subexpression in response to a given assertion attempt, at least to the extent it has been determined by the end of the evaluation period (e.g. pass, fail or indeterminate). In another embodiment, the status information reported for an intermediate subexpression contains a tick-by-tick analysis of the activity within that subexpression. In another embodiment, the status information for a subexpression can also contain a tick-by-tick analysis of the activity of an operator of the subexpression. Other kinds and levels of detail at the subexpression level can be provided in various other embodiments.