[PATCH] D44698: [Support/Parallel] Use lock_guard which has less overhead than unique_lock.

[George Rimar via Phabricator via llvm-commits]

grimar accepted this revision.
grimar added a comment.
This revision is now accepted and ready to land.

`std::condition_variable::wait` requires `unique_lock`, but in other methods `lock_guard` should be enough,
I guess `unique_lock` is now there simply because of code copy-paste. So this change is LGTM.
Please wait for another opinion though, just in case.


Repository:
  rL LLVM

https://reviews.llvm.org/D44698