Avoid checking for WTFThreadData::staticData in wtfThreadData()

third_party/WebKit/Source/wtf/ThreadSpecific.h

 /*
  * Copyright (C) 2008 Apple Inc. All rights reserved.
  * Copyright (C) 2009 Jian Li <jianli@chromium.org>
  * Copyright (C) 2012 Patrick Gansterer <paroga@paroga.com>
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
@@ skipping 55 matching lines @@
 WTF_EXPORT void ThreadSpecificThreadExit();
 #endif
 
 template <typename T>
 class ThreadSpecific {
   USING_FAST_MALLOC(ThreadSpecific);
   WTF_MAKE_NONCOPYABLE(ThreadSpecific);
 
  public:
   ThreadSpecific();
-  bool
-  isSet();  // Useful as a fast check to see if this thread has set this value.
+
+  // Useful as a fast check to see if this thread has set this value.
+  bool isSet();
+
+  // Must only be called during thread initialization.
+  void initializeOnOffThread();

[esprehn, 2017/01/19 23:47:45]

OnOffThread is weirdly named, did this lose a word? :P

[Charlie Harrison, 2017/01/19 23:54:41]

Nope, I'm just awkward at naming things :P

+  void initializeOnMainThread();
   T* operator->();
   operator T*();
   T& operator*();
 
  private:
 #if OS(WIN)
   WTF_EXPORT friend void ThreadSpecificThreadExit();
 #endif
 
   // Not implemented. It's technically possible to destroy a thread specific
@@ skipping 145 matching lines @@
   // We want get() to keep working while data destructor works, because it can
   // be called indirectly by the destructor.  Some pthreads implementations
   // zero out the pointer before calling destroy(), so we temporarily reset it.
   pthread_setspecific(data->owner->m_key, ptr);
 #endif
 
   // Never call destructors on the main thread. This is fine because Blink no
   // longer has a graceful shutdown sequence. Be careful to call this function
   // (which can be re-entrant) while the pointer is still set, to avoid lazily
   // allocating WTFThreadData after it is destroyed.
-  if (isMainThread())
+  if (internal::isMainThreadSyscall())
     return;
 
   data->value->~T();
   Partitions::fastFree(data->value);
 
 #if OS(POSIX)
   pthread_setspecific(data->owner->m_key, 0);
 #elif OS(WIN)
   TlsSetValue(tlsKeys()[data->owner->m_index], 0);
 #else
@@ skipping 29 matching lines @@
   if (UNLIKELY(!*ptr)) {
     *ptr = static_cast<T*>(Partitions::fastZeroedMalloc(
         sizeof(T), WTF_HEAP_PROFILER_TYPE_NAME(T)));
     set(*ptr);
     new (NotNull, *ptr) T;
   }
   return *ptr;
 }
 
 template <typename T>
+inline void ThreadSpecific<T>::initializeOnOffThread() {}
+template <typename T>
+inline void ThreadSpecific<T>::initializeOnMainThread() {}
+
+template <typename T>
 inline T* ThreadSpecific<T>::operator->() {
   return operator T*();
 }
 
 template <typename T>
 inline T& ThreadSpecific<T>::operator*() {
   return *operator T*();
 }
 
 }  // namespace WTF
 
 using WTF::ThreadSpecific;
 
 #endif  // WTF_ThreadSpecific_h