Folks who have been following Breker for a while know that we like the phrase “begin with the end in mind.” It succinctly summarizes why our use of graph-based scenario models is different than traditional constrained-random testbenches.
Suppose that you want to trigger a particular behavior within your design as part of your verification process. With a testbench, you have control over only the design’s inputs, so you might issue a series of input stimulus changes that you believe will cause the desired behavior. You may hit your target, or you may not. Automating your testbench with the constrained-random capabilities of the Universal Verification Methodology (UVM) reduces the manual effort, but there’s still no guarantee that you will trigger your targeted behavior.
