How to debug?

If you have 20 tests in regression, All are passing, one before the delivery all are failing. How would you debug this ?

In reply to rambarki.satish:

If you have 20 tests in regression, All are passing, one before the delivery all are failing. How would you debug this ?

If I were you, I execute diff command for all changed files before and after regression, double check these changes including RTL and testbench to make sure they are good.

In reply to chris_le:

I’d first rank the tests to find out the importance of the failing test. Secondly I’d try to find out why it is failing and where it comes from. And you could also set the UVM_VERBOSITY to UVM_DEBUG.