1 files changed, 90 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Support/ManagedStatic.cpp b/contrib/llvm/lib/Support/ManagedStatic.cpp
new file mode 100644
index 000000000000..b8fb2841e525
--- /dev/null
+++ b/contrib/llvm/lib/Support/ManagedStatic.cpp
@@ -0,0 +1,90 @@
+//===-- ManagedStatic.cpp - Static Global wrapper -------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the ManagedStatic class and llvm_shutdown().
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Support/ManagedStatic.h"
+#include "llvm/Config/config.h"
+#include "llvm/Support/Atomic.h"
+#include "llvm/Support/Mutex.h"
+#include "llvm/Support/MutexGuard.h"
+#include <cassert>
+using namespace llvm;
+
+static const ManagedStaticBase *StaticList = nullptr;
+
+static sys::Mutex& getManagedStaticMutex() {
+  // We need to use a function local static here, since this can get called
+  // during a static constructor and we need to guarantee that it's initialized
+  // correctly.
+  static sys::Mutex ManagedStaticMutex;
+  return ManagedStaticMutex;
+}
+
+void ManagedStaticBase::RegisterManagedStatic(void *(*Creator)(),
+                                              void (*Deleter)(void*)) const {
+  assert(Creator);
+  if (llvm_is_multithreaded()) {
+    MutexGuard Lock(getManagedStaticMutex());
+
+    if (!Ptr) {
+      void* tmp = Creator();
+
+      TsanHappensBefore(this);
+      sys::MemoryFence();
+
+      // This write is racy against the first read in the ManagedStatic
+      // accessors. The race is benign because it does a second read after a
+      // memory fence, at which point it isn't possible to get a partial value.
+      TsanIgnoreWritesBegin();
+      Ptr = tmp;
+      TsanIgnoreWritesEnd();
+      DeleterFn = Deleter;
+      
+      // Add to list of managed statics.
+      Next = StaticList;
+      StaticList = this;
+    }
+  } else {
+    assert(!Ptr && !DeleterFn && !Next &&
+           "Partially initialized ManagedStatic!?");
+    Ptr = Creator();
+    DeleterFn = Deleter;
+  
+    // Add to list of managed statics.
+    Next = StaticList;
+    StaticList = this;
+  }
+}
+
+void ManagedStaticBase::destroy() const {
+  assert(DeleterFn && "ManagedStatic not initialized correctly!");
+  assert(StaticList == this &&
+         "Not destroyed in reverse order of construction?");
+  // Unlink from list.
+  StaticList = Next;
+  Next = nullptr;
+
+  // Destroy memory.
+  DeleterFn(Ptr);
+  
+  // Cleanup.
+  Ptr = nullptr;
+  DeleterFn = nullptr;
+}
+
+/// llvm_shutdown - Deallocate and destroy all ManagedStatic variables.
+void llvm::llvm_shutdown() {
+  MutexGuard Lock(getManagedStaticMutex());
+
+  while (StaticList)
+    StaticList->destroy();
+}