[clang] [llvm] [ThinLTO][Split] Split module for parallel compilation in backend (1/N) (PR #198702)

[Teresa Johnson via cfe-commits]

================

----------------
teresajohnson wrote:

Does it matter that the iteration order will be non-deterministic (indexed by pointers)? If determinism isn't needed, prefer DenseMap.

https://github.com/llvm/llvm-project/pull/198702