Revert https://codereview.chromium.org/1291903002 (protobuf roll).

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

Index: third_party/protobuf/src/google/protobuf/stubs/atomicops.h
diff --git a/third_party/protobuf/src/google/protobuf/stubs/atomicops.h b/third_party/protobuf/src/google/protobuf/stubs/atomicops.h
index cd20caace23b7269fb6dbc1a3ae661acc0d4d25e..ae3ba88e5fe09e80894381a8d882c7ec68e47486 100644
--- a/third_party/protobuf/src/google/protobuf/stubs/atomicops.h
+++ b/third_party/protobuf/src/google/protobuf/stubs/atomicops.h
@@ -1,6 +1,6 @@
 // Protocol Buffers - Google's data interchange format
 // Copyright 2012 Google Inc.  All rights reserved.
-// https://developers.google.com/protocol-buffers/
+// 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
@@ -56,36 +56,24 @@
 // Don't include this file for people not concerned about thread safety.
 #ifndef GOOGLE_PROTOBUF_NO_THREAD_SAFETY
 
-#include <google/protobuf/stubs/common.h>
 #include <google/protobuf/stubs/platform_macros.h>
 
 namespace google {
 namespace protobuf {
 namespace internal {
 
-#if defined(GOOGLE_PROTOBUF_ARCH_POWER)
-#if defined(_LP64) || defined(__LP64__)
-typedef int32 Atomic32;
-typedef intptr_t Atomic64;
-#else
-typedef intptr_t Atomic32;
-typedef int64 Atomic64;
-#endif
-#else
 typedef int32 Atomic32;
 #ifdef GOOGLE_PROTOBUF_ARCH_64_BIT
 // We need to be able to go between Atomic64 and AtomicWord implicitly.  This
 // means Atomic64 and AtomicWord should be the same type on 64-bit.
-#if defined(__ILP32__) || defined(GOOGLE_PROTOBUF_OS_NACL) || defined(GOOGLE_PROTOBUF_ARCH_SPARC)
+#if defined(__ILP32__) || defined(GOOGLE_PROTOBUF_OS_NACL)
 // NaCl's intptr_t is not actually 64-bits on 64-bit!
 // http://code.google.com/p/nativeclient/issues/detail?id=1162
-// sparcv9's pointer type is 32bits
 typedef int64 Atomic64;
 #else
 typedef intptr_t Atomic64;
 #endif
 #endif
-#endif
 
 // Use AtomicWord for a machine-sized pointer.  It will use the Atomic32 or
 // Atomic64 routines below, depending on your architecture.
@@ -132,9 +120,6 @@ Atomic32 Release_CompareAndSwap(volatile Atomic32* ptr,
                                 Atomic32 old_value,
                                 Atomic32 new_value);
 
-#if defined(__MINGW32__) && defined(MemoryBarrier)
-#undef MemoryBarrier
-#endif
 void MemoryBarrier();
 void NoBarrier_Store(volatile Atomic32* ptr, Atomic32 value);
 void Acquire_Store(volatile Atomic32* ptr, Atomic32 value);
@@ -186,14 +171,6 @@ Atomic64 Release_Load(volatile const Atomic64* ptr);
 GOOGLE_PROTOBUF_ATOMICOPS_ERROR
 #endif
 
-// Solaris
-#elif defined(GOOGLE_PROTOBUF_OS_SOLARIS)
-#include <google/protobuf/stubs/atomicops_internals_solaris.h>
-
-// AIX
-#elif defined(GOOGLE_PROTOBUF_OS_AIX)
-#include <google/protobuf/stubs/atomicops_internals_aix.h>
-
 // Apple.
 #elif defined(GOOGLE_PROTOBUF_OS_APPLE)
 #include <google/protobuf/stubs/atomicops_internals_macosx.h>
@@ -202,7 +179,7 @@ GOOGLE_PROTOBUF_ATOMICOPS_ERROR
 #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) && defined(__linux__)
+#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>
@@ -210,16 +187,8 @@ GOOGLE_PROTOBUF_ATOMICOPS_ERROR
 #include <google/protobuf/stubs/atomicops_internals_arm_qnx.h>
 #elif defined(GOOGLE_PROTOBUF_ARCH_MIPS) || defined(GOOGLE_PROTOBUF_ARCH_MIPS64)
 #include <google/protobuf/stubs/atomicops_internals_mips_gcc.h>
-#elif defined(__native_client__)
+#elif defined(__pnacl__)
 #include <google/protobuf/stubs/atomicops_internals_pnacl.h>
-#elif (((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4))
-#include <google/protobuf/stubs/atomicops_internals_generic_gcc.h>
-#elif defined(__clang__)
-#if __has_extension(c_atomic)
-#include <google/protobuf/stubs/atomicops_internals_generic_gcc.h>
-#else
-GOOGLE_PROTOBUF_ATOMICOPS_ERROR
-#endif
 #else
 GOOGLE_PROTOBUF_ATOMICOPS_ERROR
 #endif