[llvm] [LLVM][DWARF] Add support for .debug_names with split dwarf (PR #73872)

[David Blaikie via llvm-commits]

dwblaikie wrote:

> Yes. On page 138, section 6.1.12 "The foreign TU list immediately follows the local TU list and they both use the same index, so that if there are N local TU entries, the index for the first foreign TU is N."

Ah, great! Thanks for the chapter-and-verse!

> I am currently working on support for it in BOLT which have similar output as with "smart linking" since at that point binary is fully linked. Sorry it's not clear to me why would hash table can be skpped in that case?

Because the hash table is there for fast lookup - but if you're merging tables, you don't need fast lookup/you can walk the entries linearly when building a merged table. So far as I understand/can think of.

@cmtice - looking at `.debug_names` merging - is there some benefit to having the hash table on input? Or is that part of the `.debug_names` going to be ignored when merging? (I'd expect the latter, but perhaps I've missed something)

https://github.com/llvm/llvm-project/pull/73872