Remove ThreadHeapMode

third_party/WebKit/Source/platform/heap/ThreadState.cpp

 /*
  * Copyright (C) 2013 Google Inc. 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
@@ skipping 121 matching lines @@
     // and we need to resume the other threads.
     if (m_shouldResumeThreads)
       m_state->heap().resume();
   }
 
  private:
   ThreadState* m_state;
   bool m_shouldResumeThreads;
 };
 
-ThreadState::ThreadState(BlinkGC::ThreadHeapMode threadHeapMode)
+ThreadState::ThreadState()
     : m_thread(currentThread()),
       m_persistentRegion(WTF::makeUnique<PersistentRegion>()),
 #if OS(WIN) && COMPILER(MSVC)
       m_threadStackSize(0),
 #endif
       m_startOfStack(
           reinterpret_cast<intptr_t*>(StackFrameDepth::getStackStart())),
       m_endOfStack(
           reinterpret_cast<intptr_t*>(StackFrameDepth::getStackStart())),
       m_safePointScopeMarker(nullptr),
       m_atSafePoint(false),
       m_interruptors(),
       m_sweepForbidden(false),
       m_noAllocationCount(0),
       m_gcForbiddenCount(0),
       m_mixinsBeingConstructedCount(0),
       m_accumulatedSweepingTime(0),
       m_vectorBackingArenaIndex(BlinkGC::Vector1ArenaIndex),
       m_currentArenaAges(0),
-      m_threadHeapMode(threadHeapMode),
       m_isTerminating(false),
       m_gcMixinMarker(nullptr),
       m_shouldFlushHeapDoesNotContainCache(false),
       m_gcState(NoGCScheduled),
       m_threadLocalWeakCallbackStack(CallbackStack::create()),
       m_isolate(nullptr),
       m_traceDOMWrappers(nullptr),
       m_invalidateDeadObjectsInWrappersMarkingDeque(nullptr),
 #if defined(ADDRESS_SANITIZER)
       m_asanFakeStack(__asan_get_current_fake_stack()),
 #endif
 #if defined(LEAK_SANITIZER)
       m_disabledStaticPersistentsRegistration(0),
 #endif
       m_allocatedObjectSize(0),
       m_markedObjectSize(0),
       m_reportedMemoryToV8(0) {
   ASSERT(checkThread());
   ASSERT(!**s_threadSpecific);
   **s_threadSpecific = this;
 
-  switch (m_threadHeapMode) {
-    case BlinkGC::MainThreadHeapMode:
-      if (isMainThread()) {
-        s_mainThreadStackStart =
-            reinterpret_cast<uintptr_t>(m_startOfStack) - sizeof(void*);
-        size_t underestimatedStackSize =
-            StackFrameDepth::getUnderestimatedStackSize();
-        if (underestimatedStackSize > sizeof(void*))
-          s_mainThreadUnderestimatedStackSize =
-              underestimatedStackSize - sizeof(void*);
-        m_heap = new ThreadHeap();
-      } else {
-        m_heap = &ThreadState::mainThreadState()->heap();
-      }
-      break;
-    case BlinkGC::PerThreadHeapMode:
-      m_heap = new ThreadHeap();
-      break;
+  if (isMainThread()) {
+    s_mainThreadStackStart =
+        reinterpret_cast<uintptr_t>(m_startOfStack) - sizeof(void*);
+    size_t underestimatedStackSize =
+        StackFrameDepth::getUnderestimatedStackSize();
+    if (underestimatedStackSize > sizeof(void*)) {
+      s_mainThreadUnderestimatedStackSize =
+          underestimatedStackSize - sizeof(void*);
+    }
   }
+  m_heap = new ThreadHeap();
   ASSERT(m_heap);
   m_heap->attach(this);

[sof, 2017/01/12 08:29:30]

It is possible to now also consider simplifying ThreadHeap's tracking of
attached threads?

[keishi, 2017/01/12 08:31:40]

I am working on that next.

 
   for (int arenaIndex = 0; arenaIndex < BlinkGC::LargeObjectArenaIndex;
        arenaIndex++)
     m_arenas[arenaIndex] = new NormalPageArena(this, arenaIndex);
   m_arenas[BlinkGC::LargeObjectArenaIndex] =
       new LargeObjectArena(this, BlinkGC::LargeObjectArenaIndex);
 
   m_likelyToBePromptlyFreed =
       wrapArrayUnique(new int[likelyToBePromptlyFreedArraySize]);
   clearArenaAges();
@@ skipping 43 matching lines @@
   // explains the details.
   RELEASE_ASSERT(m_threadStackSize > 4 * 0x1000);
   m_threadStackSize -= 4 * 0x1000;
   return m_threadStackSize;
 }
 #endif
 
 void ThreadState::attachMainThread() {
   RELEASE_ASSERT(!ProcessHeap::s_shutdownComplete);
   s_threadSpecific = new WTF::ThreadSpecific<ThreadState*>();
-  new (s_mainThreadStateStorage) ThreadState(BlinkGC::MainThreadHeapMode);
+  new (s_mainThreadStateStorage) ThreadState();
 }
 
-void ThreadState::attachCurrentThread(BlinkGC::ThreadHeapMode threadHeapMode) {
+void ThreadState::attachCurrentThread() {
   RELEASE_ASSERT(!ProcessHeap::s_shutdownComplete);
-  new ThreadState(threadHeapMode);
+  new ThreadState();
 }
 
 void ThreadState::cleanupPages() {
   ASSERT(checkThread());
   for (int i = 0; i < BlinkGC::NumberOfArenas; ++i)
     m_arenas[i]->cleanupPages();
 }
 
 void ThreadState::runTerminationGC() {
   if (isMainThread()) {
@@ skipping 1574 matching lines @@
     collectGarbage(BlinkGC::NoHeapPointersOnStack, BlinkGC::GCWithSweep,
                    BlinkGC::ForcedGC);
     size_t liveObjects = heap().heapStats().markedObjectSize();
     if (liveObjects == previousLiveObjects)
       break;
     previousLiveObjects = liveObjects;
   }
 }
 
 }  // namespace blink