Earlier this year I did a webinar on the Toad for Oracle Code Analysis feature and I demonstrated how Code Analysis takes a look at your PL/SQL code and automatically runs a series of algorithms to score your code using common computer science metrics. One of the metrics it provides is McCabe's Cyclomatic Complexity.
This is a companion discussion topic for the original entry at https://blog.toadworld.com/what-is-mccabe-cyclomatic-complexity