[tracing] Adding class-wise memory statistics to blink gc memory dumps

Source/platform/heap/ThreadState.cpp

Index: Source/platform/heap/ThreadState.cpp
diff --git a/Source/platform/heap/ThreadState.cpp b/Source/platform/heap/ThreadState.cpp
index d8cdece435b143ebbc3fcebf7e01af93fcf22b28..b1f0df82434ffaa24913fcbd2707b312f8bc6132 100644
--- a/Source/platform/heap/ThreadState.cpp
+++ b/Source/platform/heap/ThreadState.cpp
@@ -33,12 +33,15 @@
 
 #include "platform/ScriptForbiddenScope.h"
 #include "platform/TraceEvent.h"
+#include "platform/heap/BlinkGCMemoryDumpProvider.h"
 #include "platform/heap/CallbackStack.h"
 #include "platform/heap/Handle.h"
 #include "platform/heap/Heap.h"
 #include "platform/heap/MarkingVisitor.h"
 #include "platform/heap/SafePoint.h"
 #include "public/platform/Platform.h"
+#include "public/platform/WebMemoryAllocatorDump.h"
+#include "public/platform/WebProcessMemoryDump.h"
 #include "public/platform/WebScheduler.h"
 #include "public/platform/WebThread.h"
 #include "public/platform/WebTraceLocation.h"
@@ -380,6 +383,18 @@ void ThreadState::visitPersistents(Visitor* visitor)
     }
 }
 
+size_t ThreadState::GCSnapshotInfo::getClassTag(const size_t gcInfoIndex)
+{
+    ClassTagMap::AddResult result = classTags.add(gcInfoIndex, classTags.size());
+    if (result.isNewEntry) {
+        liveCount.append(0);
+        deadCount.append(0);
+        liveSize.append(0);
+        deadSize.append(0);
+    }
+    return result.storedValue->value;
+}
+
 #if ENABLE(GC_PROFILING)
 const GCInfo* ThreadState::findGCInfo(Address address)
 {
@@ -1381,22 +1396,25 @@ void ThreadState::takeSnapshot(SnapshotType type)
     ASSERT(isInGC());
 
     GCSnapshotInfo info;
+    String threadDumpName = String::format("blink_gc/thread_%lu", (unsigned long)m_thread);
+    String heapsDumpName = threadDumpName + "/heaps";
+    String classesDumpName = threadDumpName + "/classes";
+
     int numberOfHeapsReported = 0;
-#define SNAPSHOT_HEAP(HeapType)                                                                                \
-    {                                                                                                          \
-        numberOfHeapsReported++;                                                                               \
-        String allocatorBaseName;                                                                              \
-        allocatorBaseName = String::format("blink_gc/thread_%lu/heaps/" #HeapType, (unsigned long)(m_thread)); \
-        switch (type) {                                                                                        \
-        case SnapshotType::HeapSnapshot:                                                                       \
-            m_heaps[HeapType##HeapIndex]->takeSnapshot(allocatorBaseName, info);                               \
-            break;                                                                                             \
-        case SnapshotType::FreelistSnapshot:                                                                   \
-            m_heaps[HeapType##HeapIndex]->takeFreelistSnapshot(allocatorBaseName);                             \
-            break;                                                                                             \
-        default:                                                                                               \
-            ASSERT_NOT_REACHED();                                                                              \
-        }                                                                                                      \
+#define SNAPSHOT_HEAP(HeapType)                                                                \
+    {                                                                                          \
+        numberOfHeapsReported++;                                                               \
+        switch (type) {                                                                        \
+        case SnapshotType::HeapSnapshot:                                                       \
+        case SnapshotType::HeapSnapshotWithClasses:                                            \
+            m_heaps[HeapType##HeapIndex]->takeSnapshot(heapsDumpName + "/" #HeapType, info);   \
+            break;                                                                             \
+        case SnapshotType::FreelistSnapshot:                                                   \
+            m_heaps[HeapType##HeapIndex]->takeFreelistSnapshot(heapsDumpName + "/" #HeapType); \
+            break;                                                                             \
+        default:                                                                               \
+            ASSERT_NOT_REACHED();                                                              \
+        }                                                                                      \
     }
 
     SNAPSHOT_HEAP(NormalPage1);
@@ -1416,6 +1434,44 @@ void ThreadState::takeSnapshot(SnapshotType type)
     ASSERT(numberOfHeapsReported == NumberOfHeaps);
 
 #undef SNAPSHOT_HEAP
+
+    if (type != SnapshotType::HeapSnapshotWithClasses)
+        return;
+
+    if (!info.classTags.size())
+        return;
+
+    Vector<String> classNameVector(info.classTags.size());
+    for (GCSnapshotInfo::ClassTagMap::iterator it = info.classTags.begin(); it != info.classTags.end(); ++it)
+        classNameVector[it->value] = Heap::gcInfo(it->key)->m_className;
+
+    size_t totalLiveCount = 0;
+    size_t totalDeadCount = 0;
+    size_t totalLiveSize = 0;
+    size_t totalDeadSize = 0;
+    for (size_t i = 0; i < classNameVector.size(); ++i) {
+        String dumpName = classesDumpName + "/" + classNameVector[i];
+        WebMemoryAllocatorDump* classDump = BlinkGCMemoryDumpProvider::instance()->createMemoryAllocatorDumpForCurrentGC(dumpName);
+        classDump->AddScalar("live_count", "objects", info.liveCount[i]);
+        classDump->AddScalar("dead_count", "objects", info.deadCount[i]);
+        classDump->AddScalar("live_size", "bytes", info.liveSize[i]);
+        classDump->AddScalar("dead_size", "bytes", info.deadSize[i]);
+
+        totalLiveCount += info.liveCount[i];
+        totalDeadCount += info.deadCount[i];
+        totalLiveSize += info.liveSize[i];
+        totalDeadSize += info.deadSize[i];
+    }
+
+    WebMemoryAllocatorDump* threadDump = BlinkGCMemoryDumpProvider::instance()->createMemoryAllocatorDumpForCurrentGC(threadDumpName);
+    threadDump->AddScalar("live_count", "objects", totalLiveCount);
+    threadDump->AddScalar("dead_count", "objects", totalDeadCount);
+    threadDump->AddScalar("live_size", "bytes", totalLiveSize);
+    threadDump->AddScalar("dead_size", "bytes", totalDeadSize);
+
+    WebMemoryAllocatorDump* heapsDump = BlinkGCMemoryDumpProvider::instance()->createMemoryAllocatorDumpForCurrentGC(heapsDumpName);
+    WebMemoryAllocatorDump* classesDump = BlinkGCMemoryDumpProvider::instance()->createMemoryAllocatorDumpForCurrentGC(classesDumpName);
+    BlinkGCMemoryDumpProvider::instance()->currentProcessMemoryDump()->AddOwnershipEdge(classesDump->guid(), heapsDump->guid());
 }
 
 #if ENABLE(GC_PROFILING)