git: 39e8b505feb0 - stable/12 - Revert r367815, so we can apply the slightly different version that landed upstream:

From: Dimitry Andric <dim_at_FreeBSD.org>
Date: Wed, 22 Dec 2021 10:06:26 UTC
The branch stable/12 has been updated by dim:

URL: https://cgit.FreeBSD.org/src/commit/?id=39e8b505feb0dcfef4c8e794d252f1d402be3f5f

commit 39e8b505feb0dcfef4c8e794d252f1d402be3f5f
Author:     Dimitry Andric <dim@FreeBSD.org>
AuthorDate: 2020-12-03 19:26:21 +0000
Commit:     Dimitry Andric <dim@FreeBSD.org>
CommitDate: 2021-12-22 10:01:23 +0000

    Revert r367815, so we can apply the slightly different version that
    landed upstream:
    
    For llvm's internal function which retrieves the number of available
    "hardware threads", use cpuset_getaffinity(2) on FreeBSD, so it will
    honor processor sets configured by the cpuset(1) command.
    
    This should make it possible to avoid e.g. lld creating a huge number of
    threads on a machine with many cores, even for linking simple programs.
    
    This will also be submitted upstream.
    
    Submitted by:   mjg
    
    (cherry picked from commit 5cc6cb2645b79b6108922957984dd86077cd7f06)
---
 contrib/llvm-project/llvm/lib/Support/Unix/Threading.inc | 11 -----------
 1 file changed, 11 deletions(-)

diff --git a/contrib/llvm-project/llvm/lib/Support/Unix/Threading.inc b/contrib/llvm-project/llvm/lib/Support/Unix/Threading.inc
index df290d2262ea..2d0aacabf092 100644
--- a/contrib/llvm-project/llvm/lib/Support/Unix/Threading.inc
+++ b/contrib/llvm-project/llvm/lib/Support/Unix/Threading.inc
@@ -26,10 +26,6 @@
 #include <pthread_np.h> // For pthread_getthreadid_np() / pthread_set_name_np()
 #endif
 
-#if defined(__FreeBSD__)
-#include <sys/cpuset.h>
-#endif
-
 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
 #include <errno.h>
 #include <sys/sysctl.h>
@@ -286,13 +282,6 @@ SetThreadPriorityResult llvm::set_thread_priority(ThreadPriority Priority) {
 #include <thread>
 
 int computeHostNumHardwareThreads() {
-#ifdef __FreeBSD__
-  cpuset_t mask;
-  CPU_ZERO(&mask);
-  if (cpuset_getaffinity(CPU_LEVEL_WHICH, CPU_WHICH_TID, -1, sizeof(mask),
-                         &mask) == 0)
-    return CPU_COUNT(&mask);
-#endif
 #ifdef __linux__
   cpu_set_t Set;
   if (sched_getaffinity(0, sizeof(Set), &Set) == 0)