We assume that these are available inside of BitcodeWriter https://github.com/llvm/llvm-project/blob/09796808802f99c30a23bc0f2cd68243764e84ab/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp#L4927, but do not currently validate this in input IR. This means that when doing reductions with automated tooling in a non-asserts build, it is pretty easy to end up with invalid IR that is not caught as invalid. Reviewers: teresajohnson, mtrofin Pull Request: https://github.com/llvm/llvm-project/pull/208948