[all-commits] [llvm/llvm-project] 3c5745: [clangd] Make background index thread count calcul...

[Sam McCall via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 3c5745cb1f3c501e551a8fa63b8f1d564c35016d
      https://github.com/llvm/llvm-project/commit/3c5745cb1f3c501e551a8fa63b8f1d564c35016d
  Author: Sam McCall <sam.mccall at gmail.com>
  Date:   2020-06-25 (Thu, 25 Jun 2020)

  Changed paths:
    M clang-tools-extra/clangd/index/Background.cpp
    M clang-tools-extra/clangd/index/Background.h
    M clang-tools-extra/clangd/index/BackgroundRebuild.h

  Log Message:
  -----------
  [clangd] Make background index thread count calculation clearer

Summary:
This confusion was inadvertently introduced in a change to the
heavyweight_hardware_concurrency API: 8404aeb56a73ab24f9b295111de3b37a37f0b841

- don't indirect through the rebuilder policy when building the thread pool
- document that rebuilder thresholds are exposed for testing only
- don't use 0 as a sentinel value for "all threads", as we use it as a
  sentinel value for "synchronous" (though unsupported for BackgroundIndex)
- rather than pick some new sentinel value, just always use 4 threads for tests

Reviewers: kadircet, aganea

Subscribers: ilya-biryukov, MaskRay, jkorous, arphaman, usaxena95, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D82352