Atomic ops: sync with Chromium.

src/atomicops_internals_x86_msvc.h

 // Copyright 2010 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 15 matching lines @@
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 // This file is an internal atomic implementation, use atomicops.h instead.
 
 #ifndef V8_ATOMICOPS_INTERNALS_X86_MSVC_H_
 #define V8_ATOMICOPS_INTERNALS_X86_MSVC_H_
 
 #include "checks.h"
 #include "win32-headers.h"
 
+#if defined(V8_HOST_ARCH_64_BIT)
+// windows.h #defines this (only on x64). This causes problems because the
+// public API also uses MemoryBarrier at the public name for this fence. So, on
+// X64, undef it, and call its documented
+// (http://msdn.microsoft.com/en-us/library/windows/desktop/ms684208.aspx)
+// implementation directly.
+#undef MemoryBarrier
+#endif
+
 namespace v8 {
 namespace internal {
 
 inline Atomic32 NoBarrier_CompareAndSwap(volatile Atomic32* ptr,
                                          Atomic32 old_value,
                                          Atomic32 new_value) {
   LONG result = InterlockedCompareExchange(
       reinterpret_cast<volatile LONG*>(ptr),
       static_cast<LONG>(new_value),
       static_cast<LONG>(old_value));
@@ skipping 17 matching lines @@
 
 inline Atomic32 NoBarrier_AtomicIncrement(volatile Atomic32* ptr,
                                           Atomic32 increment) {
   return Barrier_AtomicIncrement(ptr, increment);
 }
 
 #if !(defined(_MSC_VER) && _MSC_VER >= 1400)
 #error "We require at least vs2005 for MemoryBarrier"
 #endif
 inline void MemoryBarrier() {
+#if defined(V8_HOST_ARCH_64_BIT)
+  // See #undef and note at the top of this file.
+  __faststorefence();
+#else
   // We use MemoryBarrier from WinNT.h
   ::MemoryBarrier();
+#endif
 }
 
 inline Atomic32 Acquire_CompareAndSwap(volatile Atomic32* ptr,
                                        Atomic32 old_value,
                                        Atomic32 new_value) {
   return NoBarrier_CompareAndSwap(ptr, old_value, new_value);
 }
 
 inline Atomic32 Release_CompareAndSwap(volatile Atomic32* ptr,
                                        Atomic32 old_value,
@@ skipping 109 matching lines @@
                                        Atomic64 new_value) {
   return NoBarrier_CompareAndSwap(ptr, old_value, new_value);
 }
 
 
 #endif  // defined(_WIN64)
 
 } }  // namespace v8::internal
 
 #endif  // V8_ATOMICOPS_INTERNALS_X86_MSVC_H_