[PATCH] D36607: [Support/Parallel] - Do not spawn thread for single/last task.

[George Rimar via Phabricator via llvm-commits]

grimar added a comment.

After looking into `ThreadPoolExecutor` I think its implementation is fine.
It creates `std::thread::hardware_concurrency() - 1` threads and reuses them correctly.

So looks slowdown is caused by overhead because of using it huge amount of times for minor single tasks.
Patch still fixes it.


https://reviews.llvm.org/D36607