yonghong-song wrote: In my latest change, I remove the selftest due to clang-format does not like 'undef' in the IR. If anybody wants to run it at llvm/test/CodeGen/BPF, the gist link is https://gist.github.com/yonghong-song/11be8603ad9422f418f60b41beded047 https://github.com/llvm/llvm-project/pull/126858