Oilpan: Refactor the way we calculate heap statistics

Source/platform/heap/ThreadState.h

Index: Source/platform/heap/ThreadState.h
diff --git a/Source/platform/heap/ThreadState.h b/Source/platform/heap/ThreadState.h
index a7621cce8d357b9beb2e382802b9f7e45078c506..7e8ae44b945e37f18093aa110090c1a4432dd681 100644
--- a/Source/platform/heap/ThreadState.h
+++ b/Source/platform/heap/ThreadState.h
@@ -295,62 +295,6 @@ struct HeapTypeTrait : public HeapIndexTrait<General1Heap> { };
 FOR_EACH_TYPED_HEAP(DEFINE_TYPED_HEAP_TRAIT)
 #undef DEFINE_TYPED_HEAP_TRAIT
 
-// A HeapStats structure keeps track of the amount of memory allocated
-// for a Blink heap and how much of that memory is used for actual
-// Blink objects. These stats are used in the heuristics to determine
-// when to perform garbage collections.
-class HeapStats {
-public:
-    HeapStats() : m_totalObjectSpace(0), m_totalAllocatedSpace(0) { }
-
-    size_t totalObjectSpace() const { return m_totalObjectSpace; }
-    size_t totalAllocatedSpace() const { return m_totalAllocatedSpace; }
-
-    void add(HeapStats* other)
-    {
-        m_totalObjectSpace += other->m_totalObjectSpace;
-        m_totalAllocatedSpace += other->m_totalAllocatedSpace;
-    }
-
-    void inline increaseObjectSpace(size_t newObjectSpace)
-    {
-        m_totalObjectSpace += newObjectSpace;
-    }
-
-    void inline decreaseObjectSpace(size_t deadObjectSpace)
-    {
-        m_totalObjectSpace -= deadObjectSpace;
-    }
-
-    void inline increaseAllocatedSpace(size_t newAllocatedSpace)
-    {
-        m_totalAllocatedSpace += newAllocatedSpace;
-    }
-
-    void inline decreaseAllocatedSpace(size_t deadAllocatedSpace)
-    {
-        m_totalAllocatedSpace -= deadAllocatedSpace;
-    }
-
-    void clear()
-    {
-        m_totalObjectSpace = 0;
-        m_totalAllocatedSpace = 0;
-    }
-
-    bool operator==(const HeapStats& other)
-    {
-        return m_totalAllocatedSpace == other.m_totalAllocatedSpace
-            && m_totalObjectSpace == other.m_totalObjectSpace;
-    }
-
-private:
-    size_t m_totalObjectSpace; // Actually contains objects that may be live, not including headers.
-    size_t m_totalAllocatedSpace; // Allocated from the OS.
-
-    friend class HeapTester;
-};
-
 class PLATFORM_EXPORT ThreadState {
     WTF_MAKE_NONCOPYABLE(ThreadState);
 public:
@@ -448,6 +392,12 @@ public:
         return true;
     }
 
+    // If gcRequested returns true when a thread returns to its event
+    // loop the thread will initiate a garbage collection.
+    bool gcRequested();
+    void setGCRequested();
+    void clearGCRequested();
+
     // shouldGC and shouldForceConservativeGC implement the heuristics
     // that are used to determine when to collect garbage. If
     // shouldForceConservativeGC returns true, we force the garbage
@@ -457,14 +407,6 @@ public:
     // collect garbage at this point.
     bool shouldGC();
     bool shouldForceConservativeGC();
-    bool increasedEnoughToGC(size_t, size_t);
-    bool increasedEnoughToForceConservativeGC(size_t, size_t);
-
-    // If gcRequested returns true when a thread returns to its event
-    // loop the thread will initiate a garbage collection.
-    bool gcRequested();
-    void setGCRequested();
-    void clearGCRequested();
 
     // Was the last GC forced for testing? This is set when garbage collection
     // is forced for testing and there are pointers on the stack. It remains
@@ -713,9 +655,7 @@ public:
     void pushWeakObjectPointerCallback(void*, WeakPointerCallback);
     bool popAndInvokeWeakPointerCallback(Visitor*);
 
-    void getStats(HeapStats&);
-    void getStatsForTesting(HeapStats&);
-    HeapStats& stats() { return m_stats; }
+    size_t objectPayloadSizeForTesting();
 
     void setupHeapsForTermination();
 
@@ -790,8 +730,6 @@ private:
     void cleanup();
     void cleanupPages();
 
-    void setLowCollectionRate(bool value) { m_lowCollectionRate = value; }
-
     void performPendingSweepInParallel();
     void waitUntilSweepersDone();
     void unregisterPreFinalizerInternal(void*);
@@ -831,8 +769,6 @@ private:
     size_t m_noAllocationCount;
     bool m_inGC;
     BaseHeap* m_heaps[NumberOfHeaps];
-    HeapStats m_stats;
-    HeapStats m_statsAfterLastGC;
 
     Vector<OwnPtr<CleanupTask> > m_cleanupTasks;
     bool m_isTerminating;