[all-commits] [llvm/llvm-project] cd53de: [Support] Fix computeHostNumPhysicalCores() to res...

[Fangrui Song via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: cd53ded557c3487b8dae2f9de894fdb5b75cb8c8
      https://github.com/llvm/llvm-project/commit/cd53ded557c3487b8dae2f9de894fdb5b75cb8c8
  Author: Fangrui Song <maskray at google.com>
  Date:   2020-07-31 (Fri, 31 Jul 2020)

  Changed paths:
    M llvm/lib/Support/Host.cpp

  Log Message:
  -----------
  [Support] Fix computeHostNumPhysicalCores() to respect affinity

computeHostNumPhysicalCores() is designed to respect CPU affinity.
D84764 used sysconf(_SC_NPROCESSORS_ONLN) which does not respect
affinity.
SupportTests Threading.PhysicalConcurrency may fail if taskset -c is specified.