LLHD is greenfield code, so it’s not based on LLVM. I’m familiar with the authors both academically (15 years ago), and on an engineering level (now). I think it is definitely worth reviewing what they’re bringing to the table.

Anyways, I think the RTL market is ripe for disruption. There was a lot of great language work done by, for instance, Ronald Garcia, directly aimed at fixing pain points in HDLs, like parsmetrization.