Adding freelist statistics to blink gc dump provider.

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 941 matching lines @@
 #endif
 
     for (int i = 0; i < NumberOfHeaps; i++)
         m_heaps[i]->prepareForSweep();
 
     if (gcType == GCWithSweep) {
         setGCState(EagerSweepScheduled);
     } else if (gcType == GCWithoutSweep) {
         setGCState(LazySweepScheduled);
     } else {
-        takeSnapshot();
+        takeSnapshot(SnapshotType::HeapSnapshot);
 
         // This unmarks all marked objects and marks all unmarked objects dead.
         makeConsistentForMutator();
 
+        takeSnapshot(SnapshotType::FreelistSnapshot);
+
         // Force setting NoGCScheduled to circumvent checkThread()
         // in setGCState().
         m_gcState = NoGCScheduled;
     }
 }
 
 void ThreadState::preSweep()
 {
     checkThread();
     if (gcState() != EagerSweepScheduled && gcState() != LazySweepScheduled)
@@ skipping 389 matching lines @@
         m_vectorBackingHeapIndex = heapIndexOfVectorHeapLeastRecentlyExpanded(Vector1HeapIndex, Vector4HeapIndex);
 }
 
 void ThreadState::promptlyFreed(size_t gcInfoIndex)
 {
     size_t entryIndex = gcInfoIndex & likelyToBePromptlyFreedArrayMask;
     // See the comment in vectorBackingHeap() for why this is +3.
     m_likelyToBePromptlyFreed[entryIndex] += 3;
 }
 
-void ThreadState::takeSnapshot()
+void ThreadState::takeSnapshot(SnapshotType type)
 {
     ASSERT(isInGC());
 
     int numberOfHeapsReported = 0;
 #define SNAPSHOT_HEAP(HeapType)                                                                                \
     {                                                                                                          \
         numberOfHeapsReported++;                                                                               \
         String allocatorBaseName;                                                                              \
         allocatorBaseName = String::format("blink_gc/thread_%lu/heaps/" #HeapType, (unsigned long)(m_thread)); \
-        m_heaps[HeapType##HeapIndex]->takeSnapshot(allocatorBaseName);                                         \
+        switch (type) {                                                                                        \
+        case SnapshotType::HeapSnapshot:                                                                       \
+            m_heaps[HeapType##HeapIndex]->takeSnapshot(allocatorBaseName);                                     \
+            break;                                                                                             \
+        case SnapshotType::FreelistSnapshot:                                                                   \
+            m_heaps[HeapType##HeapIndex]->takeFreelistSnapshot(allocatorBaseName);                             \
+            break;                                                                                             \
+        default:                                                                                               \
+            ASSERT_NOT_REACHED();                                                                              \
+        }                                                                                                      \
     }
 
     SNAPSHOT_HEAP(NormalPage1);
     SNAPSHOT_HEAP(NormalPage2);
     SNAPSHOT_HEAP(NormalPage3);
     SNAPSHOT_HEAP(NormalPage4);
     SNAPSHOT_HEAP(EagerSweep);
     SNAPSHOT_HEAP(Vector1);
     SNAPSHOT_HEAP(Vector2);
     SNAPSHOT_HEAP(Vector3);
@@ skipping 98 matching lines @@
         json->beginArray(it->key.ascii().data());
         for (size_t age = 0; age <= maxHeapObjectAge; ++age)
             json->pushInteger(it->value.ages[age]);
         json->endArray();
     }
     TRACE_EVENT_OBJECT_SNAPSHOT_WITH_ID(TRACE_DISABLED_BY_DEFAULT("blink_gc"), statsName, this, json.release());
 }
 #endif
 
 } // namespace blink