Implemented an averaging object histogram in the vm.

runtime/vm/isolate.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/isolate.h"
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "platform/json.h"
 #include "lib/mirrors.h"
 #include "vm/code_observers.h"
 #include "vm/compiler_stats.h"
 #include "vm/dart_api_state.h"
 #include "vm/dart_entry.h"
 #include "vm/debugger.h"
 #include "vm/heap.h"
+#include "vm/heap_histogram.h"
 #include "vm/message_handler.h"
 #include "vm/object_store.h"
 #include "vm/parser.h"
 #include "vm/port.h"
 #include "vm/simulator.h"
 #include "vm/stack_frame.h"
 #include "vm/stub_code.h"
 #include "vm/symbols.h"
 #include "vm/thread.h"
 #include "vm/timer.h"
 #include "vm/visitor.h"
 
 namespace dart {
 
 DEFINE_FLAG(bool, report_usage_count, false,
             "Track function usage and report.");
 DEFINE_FLAG(bool, trace_isolates, false,
             "Trace isolate creation and shut down.");
 DECLARE_FLAG(bool, trace_deoptimization_verbose);
 
+
+void Isolate::RegisterClass(const Class& cls) {
+  class_table()->Register(cls);
+  if (object_histogram() != NULL) object_histogram()->RegisterClass(cls);
+}
+
+
 class IsolateMessageHandler : public MessageHandler {
  public:
   explicit IsolateMessageHandler(Isolate* isolate);
   ~IsolateMessageHandler();
 
   const char* name() const;
   void MessageNotify(Message::Priority priority);
   bool HandleMessage(Message* message);
 
 #if defined(DEBUG)
@@ skipping 346 matching lines @@
       gc_epilogue_callbacks_(),
       deopt_cpu_registers_copy_(NULL),
       deopt_fpu_registers_copy_(NULL),
       deopt_frame_copy_(NULL),
       deopt_frame_copy_size_(0),
       deferred_boxes_(NULL),
       deferred_object_refs_(NULL),
       deferred_objects_count_(0),
       deferred_objects_(NULL),
       stacktrace_(NULL),
-      stack_frame_index_(-1) {
+      stack_frame_index_(-1),
+      object_histogram_(NULL) {
+  if (FLAG_print_object_histogram && (Dart::vm_isolate() != NULL)) {
+    object_histogram_ = new ObjectHistogram(this);
+  }
 }
 
 
 Isolate::~Isolate() {
   delete [] name_;
   delete heap_;
   delete object_store_;
   delete api_state_;
   delete stub_code_;
   delete debugger_;
 #if defined(USING_SIMULATOR)
   delete simulator_;
 #endif
   delete mutex_;
   mutex_ = NULL;  // Fail fast if interrupts are scheduled on a dead isolate.
   delete message_handler_;
   message_handler_ = NULL;  // Fail fast if we send messages to a dead isolate.
+  delete object_histogram_;
 }
 
 void Isolate::SetCurrent(Isolate* current) {
   Thread::SetThreadLocal(isolate_key, reinterpret_cast<uword>(current));
 }
 
 
 // The single thread local key which stores all the thread local data
 // for a thread. Since an Isolate is the central repository for
 // storing all isolate specific information a single thread local key
@@ skipping 291 matching lines @@
  private:
   DISALLOW_COPY_AND_ASSIGN(FinalizeWeakPersistentHandlesVisitor);
 };
 
 
 void Isolate::Shutdown() {
   ASSERT(this == Isolate::Current());
   ASSERT(top_resource() == NULL);
   ASSERT((heap_ == NULL) || heap_->Verify());
 
+  if (FLAG_print_object_histogram) {
+    StackZone stack_zone(this);
+    HandleScope handle_scope(this);
+    heap()->CollectAllGarbage();
+    object_histogram()->Print();
+  }
+
   // Clean up debugger resources. Shutting down the debugger
   // requires a handle zone. We must set up a temporary zone because
   // Isolate::Shutdown is called without a zone.
   {
     StackZone zone(this);
     HandleScope handle_scope(this);
     debugger_->Shutdown();
   }
 
   // Close all the ports owned by this isolate.
@@ skipping 396 matching lines @@
   return func.raw();
 }
 
 
 void IsolateSpawnState::Cleanup() {
   SwitchIsolateScope switch_scope(isolate());
   Dart::ShutdownIsolate();
 }
 
 }  // namespace dart