Move atomic operations' definitions out of line. While this seems kind of silly,

all kinds of problems caused by including windows.h and/or config.h in an LLVM header.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72174 91177308-0d34-0410-b5e6-96231b3b80d8

lib/System/Atomic.cpp

@@ -0,0 +1,52 @@
+//===-- Atomic.cpp - Atomic Operations --------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+//  This header file implements atomic operations.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/System/Atomic.h"
+#include "llvm/Config/config.h"
+
+using namespace llvm;
+
+#if defined(_MSC_VER)
+#include <windows.h>
+#endif
+
+void sys::MemoryFence() {
+#if LLVM_MULTITHREADED==0
+  return;
+#else
+#  if defined(__GNUC__)
+  __sync_synchronize();
+#  elif defined(_MSC_VER)
+  MemoryBarrier();
+#  else
+# error No memory fence implementation for your platform!
+#  endif
+#endif
+}
+
+sys::cas_flag sys::CompareAndSwap(volatile sys::cas_flag* ptr,
+	                                sys::cas_flag new_value,
+	                                sys::cas_flag old_value) {
+#if LLVM_MULTITHREADED==0
+  T result = *dest;
+  if (result == c)
+    *dest = exc;
+  return result;
+#elif defined(__GNUC__)
+  return __sync_val_compare_and_swap(ptr, old_value, new_value);
+#elif defined(_MSC_VER)
+	return InterlockedCompareExchange(ptr, new_value, old_value);
+#else
+#  error No compare-and-swap implementation for your platform!
+#endif
+}