Directly emit LLVM IR?

Hello! I'm interested in using LLVM as a target for a compiler I've
written in common lisp (SBCL). While I looked at perhaps wrapping the
LLVM C++ interface, wrapping C++ in, well, anything not C++ is a pain.
Someone on IRC mentioned that they didn't think I'd miss out on any
functionality by directly emitting IR, but suggested I query the list.

Do I miss out on any optimizations or other neat trickery by using the
IR directly? Does anyone know of any other platforms which directly
target LLVM via emitting IR?

Thanks,
      ...Eric Jonas