Open source but my impression is that this contains verilog generated by another program?
Could you point at some examples? It's not unusual for things to be code-generated and it doesn't necessarily impact the license.
All the RTL basically. It’s in a directory called gen_rtl (generated RTL?) and has remarkably few comments for such a complex code base.
Also although technically it's open source if it's generated verilog then isn't that a lot less useful than the code that was used to generate the rtl?