[lld] [LLD][COFF] Demangle ARM64EC export names. (PR #87068)

[Eli Friedman via llvm-commits]

https://github.com/efriedma-quic approved this pull request.

LGTM

So it does do demangling, but only in specific places, as necessary to support specific features.  That seems to match my experience with weird linker errors...

> likely due to a UTF-8/UTF-16 mismatch in link.exe

If you reinterpret UTF-16 `昣湵c` as UTF-8, it is indeed #func.

https://github.com/llvm/llvm-project/pull/87068