[llvm] [RFC] Emit dwarf data for signature-changed or new functions (PR #157349)

[via llvm-commits]

yonghong-song wrote:

For
>  (1) the tool (pahole?) will correctly identify the signature of _Z3mulii,

For C language, the linkage_name will likely be the same function name.

https://github.com/llvm/llvm-project/pull/157349