Have you seen how TruffleRuby makes use of LLVM bitcode, to ship C compiler as well?

I haven't, but not surprised given some of the very aggressive (in a good way) things they've done to address performance. It's impressive. I spoke to Chris Seaton back when it was getting started, and loved many of the things they were doing. Personally I want something leaner, and self-hosting, but that's also why mine is still experimental and wildly incomplete and TruffleRuby works for a lot of things.