[llvm] [llvm-dwarfdump] Make --verify for .debug_names multithreaded. (PR #127281)

[Alexander Yermolovich via llvm-commits]

ayermolo wrote:

Unfortunately adding lock_guard to DWARFVerifier::getNames kills all the performance. :(
it invokes DIE.getShortName() which does recursive traversal of DIEs. This can include references to other CUs, thinlto case, or type units.  Which triggers extracting all the DIEs for that TU/CU.
Will need to think how to refactor this.

https://github.com/llvm/llvm-project/pull/127281