Cherry pick r573 from upstream protobuf

third_party/protobuf/src/google/protobuf/stubs/atomicops.h

 // Protocol Buffers - Google's data interchange format
 // Copyright 2012 Google Inc.  All rights reserved.
 // http://code.google.com/p/protobuf/
 //
 // 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.
@@ skipping 167 matching lines @@
 // GCC.
 #elif defined(__GNUC__)
 #if defined(GOOGLE_PROTOBUF_ARCH_IA32) || defined(GOOGLE_PROTOBUF_ARCH_X64)
 #include <google/protobuf/stubs/atomicops_internals_x86_gcc.h>
 #elif defined(GOOGLE_PROTOBUF_ARCH_ARM)
 #include <google/protobuf/stubs/atomicops_internals_arm_gcc.h>
 #elif defined(GOOGLE_PROTOBUF_ARCH_AARCH64)
 #include <google/protobuf/stubs/atomicops_internals_arm64_gcc.h>
 #elif defined(GOOGLE_PROTOBUF_ARCH_ARM_QNX)
 #include <google/protobuf/stubs/atomicops_internals_arm_qnx.h>
-#elif defined(GOOGLE_PROTOBUF_ARCH_MIPS)
+#elif defined(GOOGLE_PROTOBUF_ARCH_MIPS) || defined(GOOGLE_PROTOBUF_ARCH_MIPS64)
 #include <google/protobuf/stubs/atomicops_internals_mips_gcc.h>
 #elif defined(__pnacl__)
 #include <google/protobuf/stubs/atomicops_internals_pnacl.h>
 #else
 GOOGLE_PROTOBUF_ATOMICOPS_ERROR
 #endif
 
 // Unknown.
 #else
 GOOGLE_PROTOBUF_ATOMICOPS_ERROR
 #endif
 
 // On some platforms we need additional declarations to make AtomicWord
 // compatible with our other Atomic* types.
 #if defined(GOOGLE_PROTOBUF_OS_APPLE)
 #include <google/protobuf/stubs/atomicops_internals_atomicword_compat.h>
 #endif
 
 #undef GOOGLE_PROTOBUF_ATOMICOPS_ERROR
 
 #endif  // GOOGLE_PROTOBUF_NO_THREAD_SAFETY
 
 #endif  // GOOGLE_PROTOBUF_ATOMICOPS_H_