Standardized Functional Verification- P9:Every manager who brings a design to tape-out or who purchases IP must eventually face these questions. The ability to answer these questions based on quantitative analysis is both vital and yet elusive. In spite of the enormous technical advances made in IC development and verification software, the answers to these questions are still based largely on guesswork and hand waving. | A Little Graph Theory 65 As mentioned earlier in this chapter there are special cases corresponding to scenarios and there are special cases corresponding to properties such as performance. It should be apparent by now that every scenario described in prose text can be described more precisely as one or more VTGs and these scenarios don t define additional points in the functional space. They are simply natural-language descriptions of specific function points or trajectories. That doesn t mean that we simply disregard them however. It means they are of interest for one reason or another and merit observation. These scenarios have raised some specific doubts on the part of one or more engineers or managers and confidence is sought that there is no bug associated with the behavior. Perhaps a special case represents some extreme of power consumption or some new compiler idioms for a superscalar processor still under development or perhaps an area of functionality that has been notoriously buggy in other projects. If a special case does lead us to defining a new variable not already represented in P then it means that our initial interpretation overlooked some information in the specification or that the specification document itself was incomplete or unclear on the subject. The higher-level special cases define properties of the target and do not contribute to the functional space as modeled by vectors of values of variables. These special cases remain in the written record the verification plan that is - see chapter 4 because they must also undergo testing to verify the properties described. In both sub-categories scenarios and properties our list of special cases does not add function points to the space so Py 0. So we now have a slightly more refined estimate compared to Eq. of the upper bound on the number of function points as P Pk Pa Pc Ps Pr. A Little Graph Theory Earlier in this chapter we observed that for each clock domain in each instance
