Code coverage is a crucial component of verification, and it is used to ensure that the design-under-test (DUT) is properly tested. Code coverage helps to identify untested or under-tested parts of the design, which may contain bugs or errors that could impact the functionality of the design.
Constraint Random Verification (CRV) is a technique for generating randomized test cases with specific constraints to ensure that the generated input stimuli meet certain design requirements.
In CRV, a set of constraints that capture the requirements of the design, such as data ranges, timing requirements, and interface protocols are defined. The testbench then generates a set of input stimuli that satisfies these constraints. The generated test cases can then be used to verify the design's functionality and performance.
CRV is a popular verification technique because it can generate a large number of randomized test cases that cover a wide range of scenarios. By using CRV, a verification engineer can quickly identify potential design bugs that may not be found using other verification techniques.
Directed verification is a type of functional verification in which the test cases are created to exercise specific features or functions of a digital design. The test cases are designed based on the knowledge of the design specification and the intended behavior of the design. Directed verification is often used in the early stages of the verification process, before random or stress testing is performed, as it can help to quickly identify bugs and ensure that the basic functionality of the design is correct.