[openmp] [clang-tools-extra] [libcxx] [mlir] [clang] [compiler-rt] [lldb] [llvm] [libcxxabi] [flang] [MachineCopyPropagation] When the source of PreviousCopy is undef, we cannot replace sub register (PR #74682)

[David Green via cfe-commits]

davemgreen wrote:

Thanks. It sounds like there are not a lot of code changes, which is a good sign. I didn't expect the debug problems though.

I'll try and take a look at the patch. Perhaps you are right that we need a new method for the debug info to use.

https://github.com/llvm/llvm-project/pull/74682