Obfuscation/software watermarking backend

I’d like to know if there is any known project doing obfucated code generation or software watermarking in LLVM.

The [obfucation/software watermarking] in machine instruction level usually requires to insert dead code, constant “unfolding”, computationally intensive “opaque predicate”, redundant calculation, duplicated calculation, etc, which all make the program inefficient.

But it seems to be possible to generate the code in an [obfucated/watermarked] manner in the first place so that the code generated in this way may not be so optimized but it’s more efficient than applying an additional (independent) obfucation pass later.