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diff --git a/contrib/llvm-project/llvm/lib/Support/Threading.cpp b/contrib/llvm-project/llvm/lib/Support/Threading.cpp
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+//===-- llvm/Support/Threading.cpp- Control multithreading mode --*- C++ -*-==//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines helper functions for running LLVM in a multi-threaded
+// environment.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Support/Threading.h"
+#include "llvm/Config/config.h"
+#include "llvm/Config/llvm-config.h"
+
+#include <cassert>
+#include <errno.h>
+#include <optional>
+#include <stdlib.h>
+#include <string.h>
+
+using namespace llvm;
+
+//===----------------------------------------------------------------------===//
+//=== WARNING: Implementation here must contain only TRULY operating system
+//===          independent code.
+//===----------------------------------------------------------------------===//
+
+#if LLVM_ENABLE_THREADS == 0 ||                                                \
+    (!defined(_WIN32) && !defined(HAVE_PTHREAD_H))
+uint64_t llvm::get_threadid() { return 0; }
+
+uint32_t llvm::get_max_thread_name_length() { return 0; }
+
+void llvm::set_thread_name(const Twine &Name) {}
+
+void llvm::get_thread_name(SmallVectorImpl<char> &Name) { Name.clear(); }
+
+llvm::BitVector llvm::get_thread_affinity_mask() { return {}; }
+
+unsigned llvm::ThreadPoolStrategy::compute_thread_count() const {
+  // When threads are disabled, ensure clients will loop at least once.
+  return 1;
+}
+
+// Unknown if threading turned off
+int llvm::get_physical_cores() { return -1; }
+
+#else
+
+static int computeHostNumHardwareThreads();
+
+unsigned llvm::ThreadPoolStrategy::compute_thread_count() const {
+  int MaxThreadCount =
+      UseHyperThreads ? computeHostNumHardwareThreads() : get_physical_cores();
+  if (MaxThreadCount <= 0)
+    MaxThreadCount = 1;
+  // Damage control threading.
+  //
+  // There are no heuristics to figure out how many threads makes sense to spawn,
+  // all while rolling with all available hw threads starts being detrimental to
+  // performance really early.
+  //
+  // Work around by putting a hard cap unless the user explicitly requested a certain amount.
+  //
+  // See https://discourse.llvm.org/t/avoidable-overhead-from-threading-by-default/69160
+  // for more details.
+  if (ThreadsRequested == 0) {
+    return std::min(MaxThreadCount, 4);
+  }
+  if (!Limit)
+    return ThreadsRequested;
+  return std::min((unsigned)MaxThreadCount, ThreadsRequested);
+}
+
+// Include the platform-specific parts of this class.
+#ifdef LLVM_ON_UNIX
+#include "Unix/Threading.inc"
+#endif
+#ifdef _WIN32
+#include "Windows/Threading.inc"
+#endif
+
+// Must be included after Threading.inc to provide definition for llvm::thread
+// because FreeBSD's condvar.h (included by user.h) misuses the "thread"
+// keyword.
+#include "llvm/Support/thread.h"
+
+#if defined(__APPLE__)
+  // Darwin's default stack size for threads except the main one is only 512KB,
+  // which is not enough for some/many normal LLVM compilations. This implements
+  // the same interface as std::thread but requests the same stack size as the
+  // main thread (8MB) before creation.
+const std::optional<unsigned> llvm::thread::DefaultStackSize = 8 * 1024 * 1024;
+#else
+const std::optional<unsigned> llvm::thread::DefaultStackSize;
+#endif
+
+
+#endif
+
+std::optional<ThreadPoolStrategy>
+llvm::get_threadpool_strategy(StringRef Num, ThreadPoolStrategy Default) {
+  if (Num == "all")
+    return llvm::hardware_concurrency();
+  if (Num.empty())
+    return Default;
+  unsigned V;
+  if (Num.getAsInteger(10, V))
+    return std::nullopt; // malformed 'Num' value
+  if (V == 0)
+    return Default;
+
+  // Do not take the Default into account. This effectively disables
+  // heavyweight_hardware_concurrency() if the user asks for any number of
+  // threads on the cmd-line.
+  ThreadPoolStrategy S = llvm::hardware_concurrency();
+  S.ThreadsRequested = V;
+  return S;
+}