Revert "[C++11] Replace LLVM atomics with std::atomic."

Breaks the MSVC build.
DataStream.cpp(44): error C2552: 'llvm::Statistic::Value' : non-aggregates cannot be initialized with initializer list

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@202731 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 5 insertions, 9 deletions

diff --git a/include/llvm/Support/ManagedStatic.h b/include/llvm/Support/ManagedStatic.h
index 4a12a1ba8e..5587618d11 100644
--- a/include/llvm/Support/ManagedStatic.h
+++ b/include/llvm/Support/ManagedStatic.h
@@ -14,9 +14,9 @@
 #ifndef LLVM_SUPPORT_MANAGED_STATIC_H
 #define LLVM_SUPPORT_MANAGED_STATIC_H
 
+#include "llvm/Support/Atomic.h"
 #include "llvm/Support/Threading.h"
 #include "llvm/Support/Valgrind.h"
-#include <atomic>
 
 namespace llvm {
 
@@ -64,8 +64,7 @@ public:
   // Accessors.
   C &operator*() {
     void* tmp = Ptr;
-    if (llvm_is_multithreaded())
-      std::atomic_thread_fence(std::memory_order_seq_cst);
+    if (llvm_is_multithreaded()) sys::MemoryFence();
     if (!tmp) RegisterManagedStatic(object_creator<C>, object_deleter<C>::call);
     TsanHappensAfter(this);
 
@@ -73,8 +72,7 @@ public:
   }
   C *operator->() {
     void* tmp = Ptr;
-    if (llvm_is_multithreaded())
-      std::atomic_thread_fence(std::memory_order_seq_cst);
+    if (llvm_is_multithreaded()) sys::MemoryFence();
     if (!tmp) RegisterManagedStatic(object_creator<C>, object_deleter<C>::call);
     TsanHappensAfter(this);
 
@@ -82,8 +80,7 @@ public:
   }
   const C &operator*() const {
     void* tmp = Ptr;
-    if (llvm_is_multithreaded())
-      std::atomic_thread_fence(std::memory_order_seq_cst);
+    if (llvm_is_multithreaded()) sys::MemoryFence();
     if (!tmp) RegisterManagedStatic(object_creator<C>, object_deleter<C>::call);
     TsanHappensAfter(this);
 
@@ -91,8 +88,7 @@ public:
   }
   const C *operator->() const {
     void* tmp = Ptr;
-    if (llvm_is_multithreaded())
-      std::atomic_thread_fence(std::memory_order_seq_cst);
+    if (llvm_is_multithreaded()) sys::MemoryFence();
     if (!tmp) RegisterManagedStatic(object_creator<C>, object_deleter<C>::call);
     TsanHappensAfter(this);