Reland^2 r22105 "Remove static initializer from isolate"

src/isolate.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_ISOLATE_H_
 #define V8_ISOLATE_H_
 
 #include "include/v8-debug.h"
 #include "src/allocation.h"
 #include "src/assert-scope.h"
@@ skipping 430 matching lines @@
   enum AddressId {
 #define DECLARE_ENUM(CamelName, hacker_name) k##CamelName##Address,
     FOR_EACH_ISOLATE_ADDRESS_NAME(DECLARE_ENUM)
 #undef DECLARE_ENUM
     kIsolateAddressCount
   };
 
   // Returns the PerIsolateThreadData for the current thread (or NULL if one is
   // not currently set).
   static PerIsolateThreadData* CurrentPerIsolateThreadData() {
+    EnsureInitialized();
     return reinterpret_cast<PerIsolateThreadData*>(
         base::Thread::GetThreadLocal(per_isolate_thread_data_key_));
   }
 
   // Returns the isolate inside which the current thread is running.
   INLINE(static Isolate* Current()) {
+    EnsureInitialized();
     Isolate* isolate = reinterpret_cast<Isolate*>(
         base::Thread::GetExistingThreadLocal(isolate_key_));
     ASSERT(isolate != NULL);
     return isolate;
   }
 
   INLINE(static Isolate* UncheckedCurrent()) {
+    EnsureInitialized();
     return reinterpret_cast<Isolate*>(
         base::Thread::GetThreadLocal(isolate_key_));
   }
+
+  // Like UncheckCurrent, but returns NULL if called reentrantly during
+  // initialization.
+  INLINE(static Isolate* UncheckedReentrantCurrent()) {
+    if (!process_wide_mutex_.Pointer()->TryLock()) return NULL;
+    process_wide_mutex_.Pointer()->Unlock();
+    EnsureInitialized();
+    return reinterpret_cast<Isolate*>(
+        base::Thread::GetThreadLocal(isolate_key_));
+  }
 
   // Usually called by Init(), but can be called early e.g. to allow
   // testing components that require logging but not the whole
   // isolate.
   //
   // Safe to call more than once.
   void InitializeLoggingAndCounters();
 
   bool Init(Deserializer* des);
 
   bool IsInitialized() { return state_ == INITIALIZED; }
 
   // True if at least one thread Enter'ed this isolate.
   bool IsInUse() { return entry_stack_ != NULL; }
 
   // Destroys the non-default isolates.
   // Sets default isolate into "has_been_disposed" state rather then destroying,
   // for legacy API reasons.
   void TearDown();
 
   static void GlobalTearDown();
 
-  static void SetCrashIfDefaultIsolateInitialized();
-  // Ensures that process-wide resources and the default isolate have been
-  // allocated. It is only necessary to call this method in rare cases, for
-  // example if you are using V8 from within the body of a static initializer.
-  // Safe to call multiple times.
-  static void EnsureDefaultIsolate();
-
   // Find the PerThread for this particular (isolate, thread) combination
   // If one does not yet exist, return null.
   PerIsolateThreadData* FindPerThreadDataForThisThread();
 
   // Find the PerThread for given (isolate, thread) combination
   // If one does not yet exist, return null.
   PerIsolateThreadData* FindPerThreadDataForThread(ThreadId thread_id);
 
   // Returns the key used to store the pointer to the current isolate.
   // Used internally for V8 threads that do not execute JavaScript but still
   // are part of the domain of an isolate (like the context switcher).
   static base::Thread::LocalStorageKey isolate_key() {
+    EnsureInitialized();
     return isolate_key_;
   }
 
   // Returns the key used to store process-wide thread IDs.
   static base::Thread::LocalStorageKey thread_id_key() {
+    EnsureInitialized();
     return thread_id_key_;
   }
 
   static base::Thread::LocalStorageKey per_isolate_thread_data_key();
 
   // Mutex for serializing access to break control structures.
   base::RecursiveMutex* break_access() { return &break_access_; }
 
   Address get_address_from_id(AddressId id);
 
@@ skipping 560 matching lines @@
   void RemoveCallCompletedCallback(CallCompletedCallback callback);
   void FireCallCompletedCallback();
 
   void EnqueueMicrotask(Handle<Object> microtask);
   void RunMicrotasks();
 
   void SetUseCounterCallback(v8::Isolate::UseCounterCallback callback);
   void CountUsage(v8::Isolate::UseCounterFeature feature);
 
  private:
+  static void EnsureInitialized();
+
   Isolate();
 
   friend struct GlobalState;
   friend struct InitializeGlobalState;
 
   enum State {
     UNINITIALIZED,    // Some components may not have been allocated.
     INITIALIZED       // All components are fully initialized.
   };
 
@@ skipping 39 matching lines @@
     int entry_count;
     PerIsolateThreadData* previous_thread_data;
     Isolate* previous_isolate;
     EntryStackItem* previous_item;
 
    private:
     DISALLOW_COPY_AND_ASSIGN(EntryStackItem);
   };
 
   // This mutex protects highest_thread_id_ and thread_data_table_.
-  static base::Mutex process_wide_mutex_;
+  static base::LazyMutex process_wide_mutex_;
 
   static base::Thread::LocalStorageKey per_isolate_thread_data_key_;
   static base::Thread::LocalStorageKey isolate_key_;
   static base::Thread::LocalStorageKey thread_id_key_;
   static ThreadDataTable* thread_data_table_;
 
   // A global counter for all generated Isolates, might overflow.
   static base::Atomic32 isolate_counter_;
 
   void Deinit();
@@ skipping 352 matching lines @@
   }
 
   EmbeddedVector<char, 128> filename_;
   FILE* file_;
   int scope_depth_;
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_ISOLATE_H_