Use clustered serialization for full snapshots.

runtime/vm/clustered_snapshot.cc

+// Copyright (c) 2016, 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/clustered_snapshot.h"
+
+#include "platform/assert.h"
+#include "vm/bootstrap.h"
+#include "vm/class_finalizer.h"
+#include "vm/dart.h"
+#include "vm/dart_entry.h"
+#include "vm/exceptions.h"
+#include "vm/heap.h"
+#include "vm/lockers.h"
+#include "vm/longjump.h"
+#include "vm/native_entry.h"
+#include "vm/object.h"
+#include "vm/object_store.h"
+#include "vm/stub_code.h"
+#include "vm/symbols.h"
+#include "vm/timeline.h"
+#include "vm/version.h"
+
+namespace dart {
+
+static RawObject* AllocateUninitialized(PageSpace* old_space, intptr_t size) {
+  ASSERT(Utils::IsAligned(size, kObjectAlignment));
+  uword address = old_space->TryAllocateDataBumpLocked(size,
+                                                       PageSpace::kForceGrowth);
+  if (address == 0) {
+    FATAL("Out of memory");
+  }
+  return reinterpret_cast<RawObject*>(address + kHeapObjectTag);
+}
+
+
+void Deserializer::InitializeHeader(RawObject* raw,
+                                    intptr_t class_id,
+                                    intptr_t size,
+                                    bool is_vm_isolate,
+                                    bool is_canonical) {
+  ASSERT(Utils::IsAligned(size, kObjectAlignment));
+  uword tags = 0;
+  tags = RawObject::ClassIdTag::update(class_id, tags);
+  tags = RawObject::SizeTag::update(size, tags);
+  tags = RawObject::VMHeapObjectTag::update(is_vm_isolate, tags);
+  tags = RawObject::CanonicalObjectTag::update(is_canonical, tags);
+  raw->ptr()->tags_ = tags;
+}
+
+
+class ClassSerializationCluster : public SerializationCluster {
+ public:
+  ClassSerializationCluster() { }

[siva, 2016/06/30 00:06:08]

Maybe 
ClassSerializationCluster() ::
  predefined_(some_initial_capacity),
  objects_(some_other_initial_capacity) { }

where the capacity is based on what the array grows to currently when you
generate a snapshot.

[rmacnak, 2016/06/30 01:39:21]

For a full snapshot we actually should expect the size of the class table.

+  virtual ~ClassSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawClass* cls = Class::RawCast(object);
+    intptr_t class_id = cls->ptr()->id_;
+
+    if (class_id < kNumPredefinedCids) {
+      // These classes are allocated by Object::Init or Object::InitOnce, so the
+      // deserializer must find them in the class table instead of allocating
+      // them.
+      predefined_.Add(cls);
+    } else {
+      objects_.Add(cls);
+    }
+
+    RawObject** from = cls->from();
+    RawObject** to = cls->to_snapshot(s->kind());
+    for (RawObject** p = from; p <= to; p++) {
+      s->Push(*p);
+    }
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kClassCid);
+    intptr_t count = predefined_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawClass* cls = predefined_[i];
+      intptr_t class_id = cls->ptr()->id_;
+      s->Write<intptr_t>(class_id);
+      s->AssignRef(cls);
+    }
+    count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawClass* cls = objects_[i];
+      s->AssignRef(cls);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+#define WRITE_CLASS()                                                          \
+    RawObject** from = cls->from();                                            \
+    RawObject** to = cls->to_snapshot(kind);                                   \
+    for (RawObject** p = from; p <= to; p++) {                                 \
+      s->WriteRef(*p);                                                         \
+    }                                                                          \
+    intptr_t class_id = cls->ptr()->id_;                                       \
+    s->WriteCid(class_id);                                                     \
+    s->Write<int32_t>(cls->ptr()->instance_size_in_words_);                    \
+    s->Write<int32_t>(cls->ptr()->next_field_offset_in_words_);                \
+    s->Write<int32_t>(cls->ptr()->type_arguments_field_offset_in_words_);      \
+    s->Write<uint16_t>(cls->ptr()->num_type_arguments_);                       \
+    s->Write<uint16_t>(cls->ptr()->num_own_type_arguments_);                   \
+    s->Write<uint16_t>(cls->ptr()->num_native_fields_);                        \
+    s->WriteTokenPosition(cls->ptr()->token_pos_);                             \
+    s->Write<uint16_t>(cls->ptr()->state_bits_);                               \

[siva, 2016/06/30 00:06:08]

Why not make this a static helper function and call it below, otherwise this
will become a very big function.

[rmacnak, 2016/06/30 01:39:21]

Done.

+
+    Snapshot::Kind kind = s->kind();
+    intptr_t count = predefined_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawClass* cls = predefined_[i];
+      WRITE_CLASS()
+    }
+    count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawClass* cls = objects_[i];
+      WRITE_CLASS()
+    }
+#undef WRITE_CLASS
+  }
+
+ private:
+  GrowableArray<RawClass*> predefined_;
+  GrowableArray<RawClass*> objects_;
+};
+
+
+class ClassDeserializationCluster : public DeserializationCluster {
+ public:
+  ClassDeserializationCluster() { }
+  virtual ~ClassDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    predefined_start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    ClassTable* table = d->isolate()->class_table();
+    for (intptr_t i = 0; i < count; i++) {
+      intptr_t class_id = d->Read<intptr_t>();
+      ASSERT(table->HasValidClassAt(class_id));
+      RawClass* cls = table->At(class_id);
+      ASSERT(cls != NULL);
+      d->AssignRef(cls);
+    }
+    predefined_stop_index_ = d->next_index();
+
+    start_index_ = d->next_index();
+    count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space,
+                                         Class::InstanceSize()));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    Snapshot::Kind kind = d->kind();
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+    ClassTable* table = d->isolate()->class_table();
+
+    for (intptr_t id = predefined_start_index_;
+         id < predefined_stop_index_;
+         id++) {
+      RawClass* cls = reinterpret_cast<RawClass*>(d->Ref(id));
+      RawObject** from = cls->from();
+      RawObject** to_snapshot = cls->to_snapshot(kind);
+      RawObject** to = cls->to();
+      for (RawObject** p = from; p <= to_snapshot; p++) {
+        *p = d->ReadRef();
+      }
+      for (RawObject** p = to_snapshot + 1; p <= to; p++) {
+        *p = Object::null();
+      }

[siva, 2016/06/30 00:06:07]

Predefined classes are allocated in Object::Init using the regular Class::New
function so they should be already null initialized right why do we need to do
this null loop again?

[rmacnak, 2016/06/30 01:39:21]

True, removed.

+
+      intptr_t class_id = d->ReadCid();
+      cls->ptr()->id_ = class_id;
+      cls->ptr()->instance_size_in_words_ = d->Read<int32_t>();
+      cls->ptr()->next_field_offset_in_words_ = d->Read<int32_t>();
+      cls->ptr()->type_arguments_field_offset_in_words_ = d->Read<int32_t>();
+      cls->ptr()->num_type_arguments_ = d->Read<uint16_t>();
+      cls->ptr()->num_own_type_arguments_ = d->Read<uint16_t>();
+      cls->ptr()->num_native_fields_ = d->Read<uint16_t>();
+      cls->ptr()->token_pos_ = d->ReadTokenPosition();
+      cls->ptr()->state_bits_ = d->Read<uint16_t>();

[siva, 2016/06/30 00:06:08]

This piece of code is repeated why not make a helper function.

+    }
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawClass* cls = reinterpret_cast<RawClass*>(d->Ref(id));
+      Deserializer::InitializeHeader(cls, kClassCid, Class::InstanceSize(),
+                                     is_vm_object);
+      RawObject** from = cls->from();
+      RawObject** to_snapshot = cls->to_snapshot(kind);
+      RawObject** to = cls->to();
+      for (RawObject** p = from; p <= to_snapshot; p++) {
+        *p = d->ReadRef();
+      }
+      for (RawObject** p = to_snapshot + 1; p <= to; p++) {
+        *p = Object::null();
+      }
+
+      intptr_t class_id = d->ReadCid();
+
+      ASSERT(class_id >= kNumPredefinedCids);
+      Instance fake;
+      cls->ptr()->handle_vtable_ = fake.vtable();
+
+      cls->ptr()->id_ = class_id;
+      cls->ptr()->instance_size_in_words_ = d->Read<int32_t>();
+      cls->ptr()->next_field_offset_in_words_ = d->Read<int32_t>();
+      cls->ptr()->type_arguments_field_offset_in_words_ = d->Read<int32_t>();
+      cls->ptr()->num_type_arguments_ = d->Read<uint16_t>();
+      cls->ptr()->num_own_type_arguments_ = d->Read<uint16_t>();
+      cls->ptr()->num_native_fields_ = d->Read<uint16_t>();
+      cls->ptr()->token_pos_ = d->ReadTokenPosition();
+      cls->ptr()->state_bits_ = d->Read<uint16_t>();
+
+      table->AllocateIndex(class_id);
+      table->SetAt(class_id, cls);
+    }
+  }
+
+  void PostLoad(const Array& refs, Snapshot::Kind kind, Zone* zone) {
+    NOT_IN_PRODUCT(TimelineDurationScope tds(Thread::Current(),
+        Timeline::GetIsolateStream(), "PostLoadClass"));
+
+    Class& cls = Class::Handle(zone);
+    for (intptr_t i = predefined_start_index_;
+         i < predefined_stop_index_;
+         i++) {
+      cls ^= refs.At(i);
+      cls.RehashConstants(zone);
+    }
+    for (intptr_t i = start_index_; i < stop_index_; i++) {
+      cls ^= refs.At(i);
+      cls.RehashConstants(zone);
+    }
+  }
+
+ private:
+  intptr_t predefined_start_index_;
+  intptr_t predefined_stop_index_;
+};
+
+class UnresolvedClassSerializationCluster : public SerializationCluster {
+ public:
+  UnresolvedClassSerializationCluster() { }
+  virtual ~UnresolvedClassSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawUnresolvedClass* cls = UnresolvedClass::RawCast(object);
+    objects_.Add(cls);
+
+    RawObject** from = cls->from();
+    RawObject** to = cls->to();
+    for (RawObject** p = from; p <= to; p++) {
+      s->Push(*p);
+    }
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kUnresolvedClassCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawUnresolvedClass* cls = objects_[i];
+      s->AssignRef(cls);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawUnresolvedClass* cls = objects_[i];
+      RawObject** from = cls->from();
+      RawObject** to = cls->to();
+      for (RawObject** p = from; p <= to; p++) {
+        s->WriteRef(*p);
+      }
+      s->WriteTokenPosition(cls->ptr()->token_pos_);
+    }
+  }
+
+ private:
+  GrowableArray<RawUnresolvedClass*> objects_;
+};
+
+class UnresolvedClassDeserializationCluster : public DeserializationCluster {
+ public:
+  UnresolvedClassDeserializationCluster() { }
+  virtual ~UnresolvedClassDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space,
+                                         UnresolvedClass::InstanceSize()));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawUnresolvedClass* cls =
+          reinterpret_cast<RawUnresolvedClass*>(d->Ref(id));
+      Deserializer::InitializeHeader(cls, kUnresolvedClassCid,
+                                     UnresolvedClass::InstanceSize(),
+                                     is_vm_object);
+      RawObject** from = cls->from();
+      RawObject** to = cls->to();
+      for (RawObject** p = from; p <= to; p++) {
+        *p = d->ReadRef();
+      }
+      cls->ptr()->token_pos_ = d->ReadTokenPosition();
+    }
+  }
+};
+
+class TypeArgumentsSerializationCluster : public SerializationCluster {
+ public:
+  TypeArgumentsSerializationCluster() { }
+  virtual ~TypeArgumentsSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawTypeArguments* type_args = TypeArguments::RawCast(object);
+    objects_.Add(type_args);
+
+    s->Push(type_args->ptr()->instantiations_);
+    intptr_t length = Smi::Value(type_args->ptr()->length_);
+    for (intptr_t i = 0; i < length; i++) {
+      s->Push(type_args->ptr()->types()[i]);
+    }
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kTypeArgumentsCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawTypeArguments* type_args = objects_[i];
+      intptr_t length = Smi::Value(type_args->ptr()->length_);
+      s->Write<intptr_t>(length);
+      s->AssignRef(type_args);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawTypeArguments* type_args = objects_[i];
+      intptr_t length = Smi::Value(type_args->ptr()->length_);
+      s->Write<intptr_t>(length);
+      s->Write<bool>(type_args->IsCanonical());
+      intptr_t hash = Smi::Value(type_args->ptr()->hash_);
+      s->Write<int32_t>(hash);
+      s->WriteRef(type_args->ptr()->instantiations_);
+      for (intptr_t j = 0; j < length; j++) {
+        s->WriteRef(type_args->ptr()->types()[j]);
+      }
+    }
+  }
+
+ private:
+  GrowableArray<RawTypeArguments*> objects_;
+};
+
+
+class TypeArgumentsDeserializationCluster : public DeserializationCluster {
+ public:
+  TypeArgumentsDeserializationCluster() { }
+  virtual ~TypeArgumentsDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      intptr_t length = d->Read<intptr_t>();
+      d->AssignRef(AllocateUninitialized(old_space,
+                                         TypeArguments::InstanceSize(length)));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawTypeArguments* type_args =
+          reinterpret_cast<RawTypeArguments*>(d->Ref(id));
+      intptr_t length = d->Read<intptr_t>();
+      bool is_canonical = d->Read<bool>();
+      Deserializer::InitializeHeader(type_args, kTypeArgumentsCid,
+                                     TypeArguments::InstanceSize(length),
+                                     is_vm_object, is_canonical);
+      type_args->ptr()->length_ = Smi::New(length);
+      type_args->ptr()->hash_ = Smi::New(d->Read<int32_t>());
+      type_args->ptr()->instantiations_ =
+          reinterpret_cast<RawArray*>(d->ReadRef());
+      for (intptr_t j = 0; j < length; j++) {
+        type_args->ptr()->types()[j] =
+            reinterpret_cast<RawAbstractType*>(d->ReadRef());
+      }
+    }
+  }
+};
+
+
+class PatchClassSerializationCluster : public SerializationCluster {
+ public:
+  PatchClassSerializationCluster() { }
+  virtual ~PatchClassSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawPatchClass* cls = PatchClass::RawCast(object);
+    objects_.Add(cls);
+
+    RawObject** from = cls->from();
+    RawObject** to = cls->to();
+    for (RawObject** p = from; p <= to; p++) {
+      s->Push(*p);
+    }
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kPatchClassCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawPatchClass* cls = objects_[i];
+      s->AssignRef(cls);
+    }
+  }

[siva, 2016/06/30 00:06:08]

The WriteAlloc function seems similar in each of the SerializationClusters can
it be made a function in the base class SerilizationCluster with a parameters
cid and length

+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawPatchClass* cls = objects_[i];
+      RawObject** from = cls->from();
+      RawObject** to = cls->to();
+      for (RawObject** p = from; p <= to; p++) {
+        s->WriteRef(*p);
+      }
+    }
+  }
+
+ private:
+  GrowableArray<RawPatchClass*> objects_;
+};
+
+class PatchClassDeserializationCluster : public DeserializationCluster {
+ public:
+  PatchClassDeserializationCluster() { }
+  virtual ~PatchClassDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space,
+                                         PatchClass::InstanceSize()));
+    }
+    stop_index_ = d->next_index();
+  }

[siva, 2016/06/30 00:06:07]

The ReadAlloc function seems similar in each of the DeserializationClusters can
it be made a function in the base class DeserializationCluster with a parameter
(size).

+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawPatchClass* cls = reinterpret_cast<RawPatchClass*>(d->Ref(id));
+      Deserializer::InitializeHeader(cls, kPatchClassCid,
+                                     PatchClass::InstanceSize(), is_vm_object);
+      RawObject** from = cls->from();
+      RawObject** to = cls->to();
+      for (RawObject** p = from; p <= to; p++) {
+        *p = d->ReadRef();
+      }
+    }
+  }
+};
+
+class FunctionSerializationCluster : public SerializationCluster {
+ public:
+  FunctionSerializationCluster() { }
+  virtual ~FunctionSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawFunction* func = Function::RawCast(object);
+    objects_.Add(func);
+
+    RawObject** from = func->from();
+    RawObject** to = func->to_snapshot();
+    for (RawObject** p = from; p <= to; p++) {
+      s->Push(*p);
+    }
+    if (s->kind() == Snapshot::kAppNoJIT) {
+      s->Push(func->ptr()->code_);
+    } else if (s->kind() == Snapshot::kAppWithJIT) {
+      s->Push(func->ptr()->unoptimized_code_);
+      s->Push(func->ptr()->ic_data_array_);
+    }
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kFunctionCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawFunction* func = objects_[i];
+      s->AssignRef(func);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    Snapshot::Kind kind = s->kind();
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawFunction* func = objects_[i];
+      RawObject** from = func->from();
+      RawObject** to = func->to_snapshot();
+      for (RawObject** p = from; p <= to; p++) {
+        s->WriteRef(*p);
+      }
+      if (kind == Snapshot::kAppNoJIT) {
+        s->WriteRef(func->ptr()->code_);
+      } else if (s->kind() == Snapshot::kAppWithJIT) {
+        s->WriteRef(func->ptr()->unoptimized_code_);
+        s->WriteRef(func->ptr()->ic_data_array_);
+      }
+
+      s->WriteTokenPosition(func->ptr()->token_pos_);
+      s->WriteTokenPosition(func->ptr()->end_token_pos_);
+      s->Write<int16_t>(func->ptr()->num_fixed_parameters_);
+      s->Write<int16_t>(func->ptr()->num_optional_parameters_);
+      s->Write<uint32_t>(func->ptr()->kind_tag_);
+      if (kind == Snapshot::kAppNoJIT) {
+        // Omit fields used to support de/reoptimization.
+      } else {
+        bool is_optimized = Code::IsOptimized(func->ptr()->code_);
+        if (is_optimized) {
+          s->Write<int32_t>(FLAG_optimization_counter_threshold);
+        } else {
+          s->Write<int32_t>(0);
+        }
+        s->Write<int8_t>(func->ptr()->deoptimization_counter_);
+        s->Write<uint16_t>(func->ptr()->optimized_instruction_count_);
+        s->Write<uint16_t>(func->ptr()->optimized_call_site_count_);
+      }
+    }
+  }
+
+ private:
+  GrowableArray<RawFunction*> objects_;
+};
+
+class FunctionDeserializationCluster : public DeserializationCluster {
+ public:
+  FunctionDeserializationCluster() { }
+  virtual ~FunctionDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space,
+                                         Function::InstanceSize()));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    Snapshot::Kind kind = d->kind();
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawFunction* func = reinterpret_cast<RawFunction*>(d->Ref(id));
+      Deserializer::InitializeHeader(func, kFunctionCid,
+                                     Function::InstanceSize(), is_vm_object);
+      RawObject** from = func->from();
+      RawObject** to_snapshot = func->to_snapshot();
+      RawObject** to = func->to();
+      for (RawObject** p = from; p <= to_snapshot; p++) {
+        *p = d->ReadRef();
+      }
+      for (RawObject** p = to_snapshot + 1; p <= to; p++) {
+        *p = Object::null();
+      }
+      if (kind == Snapshot::kAppNoJIT) {
+        func->ptr()->code_ = reinterpret_cast<RawCode*>(d->ReadRef());
+      } else if (kind == Snapshot::kAppWithJIT) {
+        func->ptr()->unoptimized_code_ =
+            reinterpret_cast<RawCode*>(d->ReadRef());
+        func->ptr()->ic_data_array_ = reinterpret_cast<RawArray*>(d->ReadRef());
+      }
+
+#if defined(DEBUG)
+      func->ptr()->entry_point_ = 0;
+#endif
+
+      func->ptr()->token_pos_ = d->ReadTokenPosition();
+      func->ptr()->end_token_pos_ = d->ReadTokenPosition();
+      func->ptr()->num_fixed_parameters_ = d->Read<int16_t>();
+      func->ptr()->num_optional_parameters_ = d->Read<int16_t>();
+      func->ptr()->kind_tag_ = d->Read<uint32_t>();
+      if (kind == Snapshot::kAppNoJIT) {
+        // Omit fields used to support de/reoptimization.
+      } else {
+        func->ptr()->usage_counter_ = d->Read<int32_t>();
+        func->ptr()->deoptimization_counter_ = d->Read<int8_t>();
+        func->ptr()->optimized_instruction_count_ = d->Read<uint16_t>();
+        func->ptr()->optimized_call_site_count_ = d->Read<uint16_t>();
+      }
+    }
+  }
+
+  void PostLoad(const Array& refs, Snapshot::Kind kind, Zone* zone) {
+    NOT_IN_PRODUCT(TimelineDurationScope tds(Thread::Current(),
+        Timeline::GetIsolateStream(), "PostLoadFunction"));
+
+    if (kind == Snapshot::kAppNoJIT) {
+      Function& func = Function::Handle(zone);
+      for (intptr_t i = start_index_; i < stop_index_; i++) {
+        func ^= refs.At(i);
+        ASSERT(func.raw()->ptr()->code_->IsCode());
+        uword entry_point = func.raw()->ptr()->code_->ptr()->entry_point_;
+        ASSERT(entry_point != 0);
+        func.raw()->ptr()->entry_point_ = entry_point;
+      }
+    } else if (kind == Snapshot::kAppWithJIT) {
+      Function& func = Function::Handle(zone);
+      Code& code = Code::Handle(zone);
+      for (intptr_t i = start_index_; i < stop_index_; i++) {
+        func ^= refs.At(i);
+        code ^= func.unoptimized_code();
+        if (!code.IsNull()) {
+          func.SetInstructions(code);
+          func.set_was_compiled(true);
+        } else {
+          func.ClearCode();
+          func.set_was_compiled(false);
+        }
+      }
+    } else {
+      Function& func = Function::Handle(zone);
+      for (intptr_t i = start_index_; i < stop_index_; i++) {
+        func ^= refs.At(i);
+        func.ClearICDataArray();
+        func.ClearCode();
+        func.set_was_compiled(false);
+      }
+    }
+  }
+};
+
+class ClosureDataSerializationCluster : public SerializationCluster {
+ public:
+  ClosureDataSerializationCluster() { }
+  virtual ~ClosureDataSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawClosureData* data = ClosureData::RawCast(object);
+    objects_.Add(data);
+
+    RawObject** from = data->from();
+    RawObject** to = data->to();
+    for (RawObject** p = from; p <= to; p++) {
+      s->Push(*p);
+    }
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kClosureDataCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawClosureData* data = objects_[i];
+      s->AssignRef(data);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawClosureData* data = objects_[i];
+      RawObject** from = data->from();
+      RawObject** to = data->to();
+      for (RawObject** p = from; p <= to; p++) {
+        s->WriteRef(*p);
+      }
+    }
+  }
+
+ private:
+  GrowableArray<RawClosureData*> objects_;
+};
+
+class ClosureDataDeserializationCluster : public DeserializationCluster {
+ public:
+  ClosureDataDeserializationCluster() { }
+  virtual ~ClosureDataDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space,
+                                         ClosureData::InstanceSize()));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawClosureData* data = reinterpret_cast<RawClosureData*>(d->Ref(id));
+      Deserializer::InitializeHeader(data, kClosureDataCid,
+                                     ClosureData::InstanceSize(), is_vm_object);
+      RawObject** from = data->from();
+      RawObject** to = data->to();
+      for (RawObject** p = from; p <= to; p++) {
+        *p = d->ReadRef();
+      }
+    }
+  }
+};
+
+class RedirectionDataSerializationCluster : public SerializationCluster {
+ public:
+  RedirectionDataSerializationCluster() { }
+  virtual ~RedirectionDataSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawRedirectionData* data = RedirectionData::RawCast(object);
+    objects_.Add(data);
+
+    RawObject** from = data->from();
+    RawObject** to = data->to();
+    for (RawObject** p = from; p <= to; p++) {
+      s->Push(*p);
+    }
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kRedirectionDataCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawRedirectionData* data = objects_[i];
+      s->AssignRef(data);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawRedirectionData* data = objects_[i];
+      RawObject** from = data->from();
+      RawObject** to = data->to();
+      for (RawObject** p = from; p <= to; p++) {
+        s->WriteRef(*p);
+      }
+    }
+  }
+
+ private:
+  GrowableArray<RawRedirectionData*> objects_;
+};
+
+class RedirectionDataDeserializationCluster : public DeserializationCluster {
+ public:
+  RedirectionDataDeserializationCluster() { }
+  virtual ~RedirectionDataDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space,
+                                         RedirectionData::InstanceSize()));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawRedirectionData* data =
+          reinterpret_cast<RawRedirectionData*>(d->Ref(id));
+      Deserializer::InitializeHeader(data, kRedirectionDataCid,
+                                     RedirectionData::InstanceSize(),
+                                     is_vm_object);
+      RawObject** from = data->from();
+      RawObject** to = data->to();
+      for (RawObject** p = from; p <= to; p++) {
+        *p = d->ReadRef();
+      }
+    }
+  }
+};
+
+class FieldSerializationCluster : public SerializationCluster {
+ public:
+  FieldSerializationCluster() { }
+  virtual ~FieldSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawField* field = Field::RawCast(object);
+    objects_.Add(field);
+
+    Snapshot::Kind kind = s->kind();
+
+    s->Push(field->ptr()->name_);
+    s->Push(field->ptr()->owner_);
+    s->Push(field->ptr()->type_);
+    // Write out the initial static value or field offset.
+    if (Field::StaticBit::decode(field->ptr()->kind_bits_)) {
+      if (kind == Snapshot::kAppNoJIT) {
+        // For precompiled static fields, the value was already reset and
+        // initializer_ now contains a Function.
+        s->Push(field->ptr()->value_.static_value_);
+      } else if (Field::ConstBit::decode(field->ptr()->kind_bits_)) {
+        // Do not reset const fields.
+        s->Push(field->ptr()->value_.static_value_);
+      } else {
+        // Otherwise, for static fields we write out the initial static value.
+        s->Push(field->ptr()->initializer_.saved_value_);
+      }
+    } else {
+      s->Push(field->ptr()->value_.offset_);
+    }
+    // Write out the initializer function or saved initial value.
+    if (kind == Snapshot::kAppNoJIT) {
+      s->Push(field->ptr()->initializer_.precompiled_);
+    } else {
+      s->Push(field->ptr()->initializer_.saved_value_);
+    }
+    if (kind != Snapshot::kAppNoJIT) {
+      // Write out the guarded list length.
+      s->Push(field->ptr()->guarded_list_length_);
+    }
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kFieldCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawField* field = objects_[i];
+      s->AssignRef(field);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    Snapshot::Kind kind = s->kind();
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawField* field = objects_[i];
+
+      s->WriteRef(field->ptr()->name_);
+      s->WriteRef(field->ptr()->owner_);
+      s->WriteRef(field->ptr()->type_);
+      // Write out the initial static value or field offset.
+      if (Field::StaticBit::decode(field->ptr()->kind_bits_)) {
+        if (kind == Snapshot::kAppNoJIT) {
+          // For precompiled static fields, the value was already reset and
+          // initializer_ now contains a Function.
+          s->WriteRef(field->ptr()->value_.static_value_);
+        } else if (Field::ConstBit::decode(field->ptr()->kind_bits_)) {
+          // Do not reset const fields.
+          s->WriteRef(field->ptr()->value_.static_value_);
+        } else {
+          // Otherwise, for static fields we write out the initial static value.
+          s->WriteRef(field->ptr()->initializer_.saved_value_);
+        }
+      } else {
+        s->WriteRef(field->ptr()->value_.offset_);
+      }
+      // Write out the initializer function or saved initial value.
+      if (kind == Snapshot::kAppNoJIT) {
+        s->WriteRef(field->ptr()->initializer_.precompiled_);
+      } else {
+        s->WriteRef(field->ptr()->initializer_.saved_value_);
+      }
+      if (kind != Snapshot::kAppNoJIT) {
+        // Write out the guarded list length.
+        s->WriteRef(field->ptr()->guarded_list_length_);
+      }
+
+      if (kind != Snapshot::kAppNoJIT) {
+        s->WriteTokenPosition(field->ptr()->token_pos_);
+        s->WriteCid(field->ptr()->guarded_cid_);
+        s->WriteCid(field->ptr()->is_nullable_);
+      }
+      s->Write<uint8_t>(field->ptr()->kind_bits_);
+    }
+  }
+
+ private:
+  GrowableArray<RawField*> objects_;
+};

[siva, 2016/06/30 00:06:08]

two blank lines between all these classes in this file?

[rmacnak, 2016/06/30 01:39:21]

Done.

+
+class FieldDeserializationCluster : public DeserializationCluster {
+ public:
+  FieldDeserializationCluster() { }
+  virtual ~FieldDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space, Field::InstanceSize()));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    Snapshot::Kind kind = d->kind();
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawField* field = reinterpret_cast<RawField*>(d->Ref(id));
+      Deserializer::InitializeHeader(field, kFieldCid,
+                                     Field::InstanceSize(), is_vm_object);
+      RawObject** from = field->from();
+      RawObject** to_snapshot = field->to_snapshot(kind);
+      RawObject** to = field->to();
+      for (RawObject** p = from; p <= to_snapshot; p++) {
+        *p = d->ReadRef();
+      }
+      for (RawObject** p = to_snapshot + 1; p <= to; p++) {
+        *p = Object::null();
+      }
+
+      if (kind != Snapshot::kAppNoJIT) {
+        field->ptr()->token_pos_ = d->ReadTokenPosition();
+        field->ptr()->guarded_cid_ = d->ReadCid();
+        field->ptr()->is_nullable_ = d->ReadCid();
+      }
+      field->ptr()->kind_bits_ = d->Read<uint8_t>();
+    }
+  }
+
+  void PostLoad(const Array& refs, Snapshot::Kind kind, Zone* zone) {
+    NOT_IN_PRODUCT(TimelineDurationScope tds(Thread::Current(),
+        Timeline::GetIsolateStream(), "PostLoadField"));
+
+    Field& field = Field::Handle(zone);
+    if (!FLAG_use_field_guards) {
+      for (intptr_t i = start_index_; i < stop_index_; i++) {
+        field ^= refs.At(i);
+        field.set_guarded_cid(kDynamicCid);
+        field.set_is_nullable(true);
+        field.set_guarded_list_length(Field::kNoFixedLength);
+        field.set_guarded_list_length_in_object_offset(
+            Field::kUnknownLengthOffset);
+      }
+    } else {
+      for (intptr_t i = start_index_; i < stop_index_; i++) {
+        field ^= refs.At(i);
+        field.InitializeGuardedListLengthInObjectOffset();
+      }
+    }
+  }
+};
+
+class LiteralTokenSerializationCluster : public SerializationCluster {
+ public:
+  LiteralTokenSerializationCluster() { }
+  virtual ~LiteralTokenSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawLiteralToken* token = LiteralToken::RawCast(object);
+    objects_.Add(token);
+
+    RawObject** from = token->from();
+    RawObject** to = token->to();
+    for (RawObject** p = from; p <= to; p++) {
+      s->Push(*p);
+    }
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kLiteralTokenCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawLiteralToken* token = objects_[i];
+      s->AssignRef(token);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawLiteralToken* token = objects_[i];
+      RawObject** from = token->from();
+      RawObject** to = token->to();
+      for (RawObject** p = from; p <= to; p++) {
+        s->WriteRef(*p);
+      }
+      s->Write<int32_t>(token->ptr()->kind_);
+    }
+  }
+
+ private:
+  GrowableArray<RawLiteralToken*> objects_;
+};
+
+class LiteralTokenDeserializationCluster : public DeserializationCluster {
+ public:
+  LiteralTokenDeserializationCluster() { }
+  virtual ~LiteralTokenDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space,
+                                         LiteralToken::InstanceSize()));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawLiteralToken* token = reinterpret_cast<RawLiteralToken*>(d->Ref(id));
+      Deserializer::InitializeHeader(token, kLiteralTokenCid,
+                                     LiteralToken::InstanceSize(),
+                                     is_vm_object);
+      RawObject** from = token->from();
+      RawObject** to = token->to();
+      for (RawObject** p = from; p <= to; p++) {
+        *p = d->ReadRef();
+      }
+      token->ptr()->kind_ = static_cast<Token::Kind>(d->Read<int32_t>());
+    }
+  }
+};
+
+class TokenStreamSerializationCluster : public SerializationCluster {
+ public:
+  TokenStreamSerializationCluster() { }
+  virtual ~TokenStreamSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawTokenStream* stream = TokenStream::RawCast(object);
+    objects_.Add(stream);
+
+    RawObject** from = stream->from();
+    RawObject** to = stream->to();
+    for (RawObject** p = from; p <= to; p++) {
+      s->Push(*p);
+    }
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kTokenStreamCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawTokenStream* stream = objects_[i];
+      s->AssignRef(stream);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawTokenStream* stream = objects_[i];
+      RawObject** from = stream->from();
+      RawObject** to = stream->to();
+      for (RawObject** p = from; p <= to; p++) {
+        s->WriteRef(*p);
+      }
+    }
+  }
+
+ private:
+  GrowableArray<RawTokenStream*> objects_;
+};
+
+class TokenStreamDeserializationCluster : public DeserializationCluster {
+ public:
+  TokenStreamDeserializationCluster() { }
+  virtual ~TokenStreamDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space,
+                                         TokenStream::InstanceSize()));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawTokenStream* stream = reinterpret_cast<RawTokenStream*>(d->Ref(id));
+      Deserializer::InitializeHeader(stream, kTokenStreamCid,
+                                     TokenStream::InstanceSize(), is_vm_object);
+      RawObject** from = stream->from();
+      RawObject** to = stream->to();
+      for (RawObject** p = from; p <= to; p++) {
+        *p = d->ReadRef();
+      }
+    }
+  }
+};
+
+class ScriptSerializationCluster : public SerializationCluster {
+ public:
+  ScriptSerializationCluster() { }
+  virtual ~ScriptSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawScript* script = Script::RawCast(object);
+    objects_.Add(script);
+
+    RawObject** from = script->from();
+    RawObject** to = script->to_snapshot(s->kind());
+    for (RawObject** p = from; p <= to; p++) {
+      s->Push(*p);
+    }
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kScriptCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawScript* script = objects_[i];
+      s->AssignRef(script);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    Snapshot::Kind kind = s->kind();
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawScript* script = objects_[i];
+      RawObject** from = script->from();
+      RawObject** to = script->to_snapshot(kind);
+      for (RawObject** p = from; p <= to; p++) {
+        s->WriteRef(*p);
+      }
+
+      s->Write<int32_t>(script->ptr()->line_offset_);
+      s->Write<int32_t>(script->ptr()->col_offset_);
+      s->Write<int8_t>(script->ptr()->kind_);
+    }
+  }
+
+ private:
+  GrowableArray<RawScript*> objects_;
+};
+
+
+class ScriptDeserializationCluster : public DeserializationCluster {
+ public:
+  ScriptDeserializationCluster() { }
+  virtual ~ScriptDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space, Script::InstanceSize()));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    Snapshot::Kind kind = d->kind();
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawScript* script = reinterpret_cast<RawScript*>(d->Ref(id));
+      Deserializer::InitializeHeader(script, kScriptCid,
+                                     Script::InstanceSize(), is_vm_object);
+      RawObject** from = script->from();
+      RawObject** to_snapshot = script->to_snapshot(kind);
+      RawObject** to = script->to();
+      for (RawObject** p = from; p <= to_snapshot; p++) {
+        *p = d->ReadRef();
+      }
+      for (RawObject** p = to_snapshot + 1; p <= to; p++) {
+        *p = Object::null();
+      }
+
+      script->ptr()->line_offset_ = d->Read<int32_t>();
+      script->ptr()->col_offset_ = d->Read<int32_t>();
+      script->ptr()->kind_ = d->Read<int8_t>();
+      script->ptr()->load_timestamp_ = 0;
+    }
+  }
+};
+
+
+class LibrarySerializationCluster : public SerializationCluster {
+ public:
+  LibrarySerializationCluster() { }
+  virtual ~LibrarySerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawLibrary* lib = Library::RawCast(object);
+    objects_.Add(lib);
+
+    RawObject** from = lib->from();
+    RawObject** to = lib->to_snapshot();
+    for (RawObject** p = from; p <= to; p++) {
+      s->Push(*p);
+    }
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kLibraryCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawLibrary* lib = objects_[i];
+      s->AssignRef(lib);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawLibrary* lib = objects_[i];
+      RawObject** from = lib->from();
+      RawObject** to = lib->to_snapshot();
+      for (RawObject** p = from; p <= to; p++) {
+        s->WriteRef(*p);
+      }
+
+      s->Write<int32_t>(lib->ptr()->index_);
+      s->Write<uint16_t>(lib->ptr()->num_imports_);
+      s->Write<int8_t>(lib->ptr()->load_state_);
+      s->Write<bool>(lib->ptr()->corelib_imported_);
+      s->Write<bool>(lib->ptr()->is_dart_scheme_);
+      s->Write<bool>(lib->ptr()->debuggable_);
+    }
+  }
+
+ private:
+  GrowableArray<RawLibrary*> objects_;
+};
+
+class LibraryDeserializationCluster : public DeserializationCluster {
+ public:
+  LibraryDeserializationCluster() { }
+  virtual ~LibraryDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space, Library::InstanceSize()));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawLibrary* lib = reinterpret_cast<RawLibrary*>(d->Ref(id));
+      Deserializer::InitializeHeader(lib, kLibraryCid,
+                                     Library::InstanceSize(), is_vm_object);
+      RawObject** from = lib->from();
+      RawObject** to_snapshot = lib->to_snapshot();
+      RawObject** to = lib->to();
+      for (RawObject** p = from; p <= to_snapshot; p++) {
+        *p = d->ReadRef();
+      }
+      for (RawObject** p = to_snapshot + 1; p <= to; p++) {
+        *p = Object::null();
+      }
+
+      lib->ptr()->native_entry_resolver_ = NULL;
+      lib->ptr()->native_entry_symbol_resolver_ = NULL;
+      lib->ptr()->index_ = d->Read<int32_t>();
+      lib->ptr()->num_imports_ = d->Read<uint16_t>();
+      lib->ptr()->load_state_ = d->Read<int8_t>();
+      lib->ptr()->corelib_imported_ = d->Read<bool>();
+      lib->ptr()->is_dart_scheme_ = d->Read<bool>();
+      lib->ptr()->debuggable_ = d->Read<bool>();
+      lib->ptr()->is_in_fullsnapshot_ = true;
+    }
+  }
+
+  void PostLoad(const Array& refs, Snapshot::Kind kind, Zone* zone) {
+    // TODO(rmacnak): This is surprisingly slow, roughly 20% of deserialization
+    // time for the JIT. Maybe make the lookups happy with a null?
+
+    NOT_IN_PRODUCT(TimelineDurationScope tds(Thread::Current(),
+        Timeline::GetIsolateStream(), "PostLoadLibrary"));
+
+    Library& lib = Library::Handle(zone);
+    for (intptr_t i = start_index_; i < stop_index_; i++) {
+      lib ^= refs.At(i);
+      const intptr_t kInitialNameCacheSize = 64;
+      lib.InitResolvedNamesCache(kInitialNameCacheSize);
+    }
+  }
+};
+
+class NamespaceSerializationCluster : public SerializationCluster {
+ public:
+  NamespaceSerializationCluster() { }
+  virtual ~NamespaceSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawNamespace* ns = Namespace::RawCast(object);
+    objects_.Add(ns);
+
+    RawObject** from = ns->from();
+    RawObject** to = ns->to();
+    for (RawObject** p = from; p <= to; p++) {
+      s->Push(*p);
+    }
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kNamespaceCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawNamespace* ns = objects_[i];
+      s->AssignRef(ns);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawNamespace* ns = objects_[i];
+      RawObject** from = ns->from();
+      RawObject** to = ns->to();
+      for (RawObject** p = from; p <= to; p++) {
+        s->WriteRef(*p);
+      }
+    }
+  }
+
+ private:
+  GrowableArray<RawNamespace*> objects_;
+};
+
+class NamespaceDeserializationCluster : public DeserializationCluster {
+ public:
+  NamespaceDeserializationCluster() { }
+  virtual ~NamespaceDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space, Namespace::InstanceSize()));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawNamespace* ns = reinterpret_cast<RawNamespace*>(d->Ref(id));
+      Deserializer::InitializeHeader(ns, kNamespaceCid,
+                                     Namespace::InstanceSize(), is_vm_object);
+      RawObject** from = ns->from();
+      RawObject** to = ns->to();
+      for (RawObject** p = from; p <= to; p++) {
+        *p = d->ReadRef();
+      }
+    }
+  }
+};
+
+class CodeSerializationCluster : public SerializationCluster {
+ public:
+  CodeSerializationCluster() { }
+  virtual ~CodeSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawCode* code = Code::RawCast(object);
+    objects_.Add(code);
+
+    s->Push(code->ptr()->object_pool_);
+    s->Push(code->ptr()->owner_);
+    s->Push(code->ptr()->exception_handlers_);
+    s->Push(code->ptr()->pc_descriptors_);
+    s->Push(code->ptr()->stackmaps_);
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kCodeCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawCode* code = objects_[i];
+      s->AssignRef(code);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    Snapshot::Kind kind = s->kind();
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawCode* code = objects_[i];
+
+      intptr_t pointer_offsets_length =
+          Code::PtrOffBits::decode(code->ptr()->state_bits_);
+      if (pointer_offsets_length != 0) {
+        FATAL("Cannot serialize code with embedded pointers");
+      }
+      if (kind == Snapshot::kAppNoJIT) {
+        // No disabled code in precompilation.
+        ASSERT(code->ptr()->instructions_ == code->ptr()->active_instructions_);
+      } else {
+        ASSERT(kind == Snapshot::kAppWithJIT);
+        // We never include optimized code in JIT precompilation. Deoptimization
+        // requires code patching and we cannot patch code that is shared
+        // between isolates and should not mutate memory allocated by the
+        // embedder.
+        bool is_optimized = Code::PtrOffBits::decode(code->ptr()->state_bits_);
+        if (is_optimized) {
+          FATAL("Cannot include optimized code in a JIT snapshot");
+        }
+      }
+
+      RawInstructions* instr = code->ptr()->instructions_;
+      int32_t text_offset = s->GetTextOffset(instr, code);
+      s->Write<int32_t>(text_offset);
+
+      s->WriteRef(code->ptr()->object_pool_);
+      s->WriteRef(code->ptr()->owner_);
+      s->WriteRef(code->ptr()->exception_handlers_);
+      s->WriteRef(code->ptr()->pc_descriptors_);
+      s->WriteRef(code->ptr()->stackmaps_);
+
+      s->Write<int32_t>(code->ptr()->state_bits_);
+    }
+  }
+
+ private:
+  GrowableArray<RawCode*> objects_;
+};
+
+class CodeDeserializationCluster : public DeserializationCluster {
+ public:
+  CodeDeserializationCluster() { }
+  virtual ~CodeDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space, Code::InstanceSize(0)));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawCode* code = reinterpret_cast<RawCode*>(d->Ref(id));
+      Deserializer::InitializeHeader(code, kCodeCid,
+                                     Code::InstanceSize(0), is_vm_object);
+
+      int32_t text_offset = d->Read<int32_t>();
+      RawInstructions* instr = reinterpret_cast<RawInstructions*>(
+          d->GetInstructionsAt(text_offset) + kHeapObjectTag);
+      uword entry_point = Instructions::EntryPoint(instr);
+
+      code->ptr()->entry_point_ = entry_point;
+      code->ptr()->active_instructions_ = instr;
+      code->ptr()->instructions_ = instr;
+      code->ptr()->object_pool_ =
+          reinterpret_cast<RawObjectPool*>(d->ReadRef());
+      code->ptr()->owner_ = d->ReadRef();
+      code->ptr()->exception_handlers_ =
+          reinterpret_cast<RawExceptionHandlers*>(d->ReadRef());
+      code->ptr()->pc_descriptors_ =
+          reinterpret_cast<RawPcDescriptors*>(d->ReadRef());
+      code->ptr()->stackmaps_ =
+          reinterpret_cast<RawArray*>(d->ReadRef());
+
+      code->ptr()->deopt_info_array_ = Array::null();
+      code->ptr()->static_calls_target_table_ = Array::null();
+      code->ptr()->var_descriptors_ = LocalVarDescriptors::null();
+      code->ptr()->inlined_metadata_ = Array::null();
+      code->ptr()->code_source_map_ = CodeSourceMap::null();
+      code->ptr()->comments_ = Array::null();
+      code->ptr()->return_address_metadata_ = Object::null();
+
+      code->ptr()->compile_timestamp_ = 0;
+      code->ptr()->state_bits_ = d->Read<int32_t>();
+      code->ptr()->lazy_deopt_pc_offset_ = -1;
+    }
+  }
+};
+
+class ObjectPoolSerializationCluster : public SerializationCluster {
+ public:
+  ObjectPoolSerializationCluster() { }
+  virtual ~ObjectPoolSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawObjectPool* pool = ObjectPool::RawCast(object);
+    objects_.Add(pool);
+
+    intptr_t length = pool->ptr()->length_;
+    RawTypedData* info_array = pool->ptr()->info_array_;
+
+    for (intptr_t i = 0; i < length; i++) {
+      ObjectPool::EntryType entry_type =
+          static_cast<ObjectPool::EntryType>(info_array->ptr()->data()[i]);
+      if (entry_type == ObjectPool::kTaggedObject) {
+        s->Push(pool->ptr()->data()[i].raw_obj_);
+      }
+    }
+
+    // We are going to allocate the object pool and its info array together,
+    // so steal a slot in the refs array to hold it between alloc and fill.
+    // s->NoteUntracedRef();

[siva, 2016/06/30 00:06:08]

Code commented out, can it be deleted?

[rmacnak, 2016/06/30 01:39:21]

-> TODO

+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kObjectPoolCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawObjectPool* pool = objects_[i];
+      /// RawTypedData* info_array = pool->ptr()->info_array_;
+      intptr_t length = pool->ptr()->length_;
+      s->Write<intptr_t>(length);
+      /// s->AssignRefNotTraced(info_array);
+      s->AssignRef(pool);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawObjectPool* pool = objects_[i];
+      RawTypedData* info_array = pool->ptr()->info_array_;
+      intptr_t length = pool->ptr()->length_;
+      s->Write<intptr_t>(length);
+      for (intptr_t j = 0; j < length; j++) {
+        ObjectPool::EntryType entry_type =
+            static_cast<ObjectPool::EntryType>(info_array->ptr()->data()[j]);
+        s->Write<int8_t>(entry_type);
+        RawObjectPool::Entry& entry = pool->ptr()->data()[j];
+        switch (entry_type) {
+          case ObjectPool::kTaggedObject: {
+#if !defined(TARGET_ARCH_DBC)
+            if (entry.raw_obj_ ==
+                StubCode::CallNativeCFunction_entry()->code()) {
+              // Natives can run while precompiling, becoming linked and
+              // switching their stub. Reset to the initial stub used for
+              // lazy-linking.
+              s->WriteRef(StubCode::CallBootstrapCFunction_entry()->code());
+              break;
+            }
+#endif
+          s->WriteRef(entry.raw_obj_);
+          break;
+        }
+        case ObjectPool::kImmediate: {
+          s->Write<intptr_t>(entry.raw_value_);
+          break;
+        }
+        case ObjectPool::kNativeEntry: {
+          // Write nothing. Will initialize with the lazy link entry.
+#if defined(TARGET_ARCH_DBC)
+          UNREACHABLE();   // DBC does not support lazy native call linking.
+#endif
+          break;
+        }
+        default:
+          UNREACHABLE();
+        }
+      }
+    }
+  }
+
+ private:
+  GrowableArray<RawObjectPool*> objects_;
+};
+
+
+class ObjectPoolDeserializationCluster : public DeserializationCluster {
+ public:
+  ObjectPoolDeserializationCluster() { }
+  virtual ~ObjectPoolDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      intptr_t length = d->Read<intptr_t>();
+      /// d->AssignRef(AllocateUninitialized(old_space,
+      ///                                    TypedData::InstanceSize(length)));
+      d->AssignRef(AllocateUninitialized(old_space,
+                                         ObjectPool::InstanceSize(length)));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+    PageSpace* old_space = d->heap()->old_space();
+    for (intptr_t id = start_index_; id < stop_index_; id += 1) {
+      intptr_t length = d->Read<intptr_t>();
+      /// RawTypedData* info_array =
+      ///     reinterpret_cast<RawTypedData*>(d->Ref(id));
+      RawTypedData* info_array = reinterpret_cast<RawTypedData*>(
+          AllocateUninitialized(old_space, TypedData::InstanceSize(length)));
+      Deserializer::InitializeHeader(info_array, kTypedDataUint8ArrayCid,
+                                     TypedData::InstanceSize(length),
+                                     is_vm_object);
+      info_array->ptr()->length_ = Smi::New(length);
+      RawObjectPool* pool = reinterpret_cast<RawObjectPool*>(d->Ref(id + 0));
+      Deserializer::InitializeHeader(pool, kObjectPoolCid,
+                                     ObjectPool::InstanceSize(length),
+                                     is_vm_object);
+      pool->ptr()->length_ = length;
+      pool->ptr()->info_array_ = info_array;
+      for (intptr_t j = 0; j < length; j++) {
+        ObjectPool::EntryType entry_type =
+            static_cast<ObjectPool::EntryType>(d->Read<int8_t>());
+        info_array->ptr()->data()[j] = entry_type;
+        RawObjectPool::Entry& entry = pool->ptr()->data()[j];
+        switch (entry_type) {
+          case ObjectPool::kTaggedObject:
+            entry.raw_obj_ = d->ReadRef();
+            break;
+          case ObjectPool::kImmediate:
+            entry.raw_value_ = d->Read<intptr_t>();
+            break;
+          case ObjectPool::kNativeEntry: {
+#if !defined(TARGET_ARCH_DBC)
+            // Read nothing. Initialize with the lazy link entry.
+            uword new_entry = NativeEntry::LinkNativeCallEntry();
+            entry.raw_value_ = static_cast<intptr_t>(new_entry);
+#else
+            UNREACHABLE();  // DBC does not support lazy native call linking.
+#endif
+            break;
+          }
+          default:
+            UNREACHABLE();
+        }
+      }
+    }
+  }
+};
+
+
+// PcDescriptor, Stackmap, OneByteString, TwoByteString
+class RODataSerializationCluster : public SerializationCluster {
+ public:
+  explicit RODataSerializationCluster(intptr_t cid) : cid_(cid) { }
+  virtual ~RODataSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    objects_.Add(object);
+
+    // A string's hash must already be computed when we write it because it
+    // will be loaded into read-only memory.
+    if (cid_ == kOneByteStringCid) {
+      RawOneByteString* str = static_cast<RawOneByteString*>(object);
+      if (str->ptr()->hash_ == Smi::New(0)) {
+        intptr_t hash = String::Hash(str->ptr()->data(),
+                                     Smi::Value(str->ptr()->length_));
+        str->ptr()->hash_ = Smi::New(hash);
+      }
+      ASSERT(str->ptr()->hash_ != Smi::New(0));
+    } else if (cid_ == kTwoByteStringCid) {
+      RawTwoByteString* str = static_cast<RawTwoByteString*>(object);
+      if (str->ptr()->hash_ == Smi::New(0)) {
+        intptr_t hash = String::Hash(str->ptr()->data(),
+                                     Smi::Value(str->ptr()->length_) * 2);
+        str->ptr()->hash_ = Smi::New(hash);
+      }
+      ASSERT(str->ptr()->hash_ != Smi::New(0));
+    }
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(cid_);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawObject* object = objects_[i];
+      int32_t rodata_offset = s->GetRODataOffset(object);
+      s->Write<int32_t>(rodata_offset);
+      s->AssignRef(object);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    // No-op.
+  }
+
+ private:
+  const intptr_t cid_;
+  GrowableArray<RawObject*> objects_;
+};
+
+
+class RODataDeserializationCluster : public DeserializationCluster {
+ public:
+  RODataDeserializationCluster() { }
+  virtual ~RODataDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      int32_t rodata_offset = d->Read<int32_t>();
+      d->AssignRef(d->GetObjectAt(rodata_offset));
+    }
+  }
+
+  void ReadFill(Deserializer* d) {
+    // No-op.
+  }
+};
+
+
+class LocalVarDescriptorsSerializationCluster : public SerializationCluster {
+ public:
+  LocalVarDescriptorsSerializationCluster() { }
+  virtual ~LocalVarDescriptorsSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) { UNIMPLEMENTED(); }
+  void WriteAlloc(Serializer* s) {}
+  void WriteFill(Serializer* s) {}
+
+ private:
+  GrowableArray<RawClass*> objects_;
+};
+
+
+class ExceptionHandlersSerializationCluster : public SerializationCluster {
+ public:
+  ExceptionHandlersSerializationCluster() { }
+  virtual ~ExceptionHandlersSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawExceptionHandlers* handlers = ExceptionHandlers::RawCast(object);
+    objects_.Add(handlers);
+
+    s->Push(handlers->ptr()->handled_types_data_);
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kExceptionHandlersCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawExceptionHandlers* handlers = objects_[i];
+      intptr_t length = handlers->ptr()->num_entries_;
+      s->Write<intptr_t>(length);
+      s->AssignRef(handlers);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawExceptionHandlers* handlers = objects_[i];
+      intptr_t length = handlers->ptr()->num_entries_;
+      s->Write<intptr_t>(length);
+      s->WriteRef(handlers->ptr()->handled_types_data_);
+
+      uint8_t* data = reinterpret_cast<uint8_t*>(handlers->ptr()->data());
+      intptr_t length_in_bytes =
+          length * sizeof(RawExceptionHandlers::HandlerInfo);
+      s->WriteBytes(data, length_in_bytes);
+    }
+  }
+
+ private:
+  GrowableArray<RawExceptionHandlers*> objects_;
+};
+
+class ExceptionHandlersDeserializationCluster : public DeserializationCluster {
+ public:
+  ExceptionHandlersDeserializationCluster() { }
+  virtual ~ExceptionHandlersDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      intptr_t length = d->Read<intptr_t>();
+      d->AssignRef(AllocateUninitialized(old_space,
+          ExceptionHandlers::InstanceSize(length)));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawExceptionHandlers* handlers =
+          reinterpret_cast<RawExceptionHandlers*>(d->Ref(id));
+      intptr_t length = d->Read<intptr_t>();
+      Deserializer::InitializeHeader(handlers, kExceptionHandlersCid,
+                                     ExceptionHandlers::InstanceSize(length),
+                                     is_vm_object);
+      handlers->ptr()->num_entries_ = length;
+      handlers->ptr()->handled_types_data_ =
+          reinterpret_cast<RawArray*>(d->ReadRef());
+
+      uint8_t* data = reinterpret_cast<uint8_t*>(handlers->ptr()->data());
+      intptr_t length_in_bytes =
+          length * sizeof(RawExceptionHandlers::HandlerInfo);
+      d->ReadBytes(data, length_in_bytes);
+    }
+  }
+};
+
+class ContextSerializationCluster : public SerializationCluster {
+ public:
+  ContextSerializationCluster() { }
+  virtual ~ContextSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawContext* context = Context::RawCast(object);
+    objects_.Add(context);
+
+    s->Push(context->ptr()->parent_);
+    intptr_t length = context->ptr()->num_variables_;
+    for (intptr_t i = 0; i < length; i++) {
+      s->Push(context->ptr()->data()[i]);
+    }
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kContextCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawContext* context = objects_[i];
+      intptr_t length = context->ptr()->num_variables_;
+      s->Write<intptr_t>(length);
+      s->AssignRef(context);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawContext* context = objects_[i];
+      intptr_t length = context->ptr()->num_variables_;
+      s->Write<intptr_t>(length);
+      s->WriteRef(context->ptr()->parent_);
+      for (intptr_t j = 0; j < length; j++) {
+        s->WriteRef(context->ptr()->data()[j]);
+      }
+    }
+  }
+
+ private:
+  GrowableArray<RawContext*> objects_;
+};
+
+class ContextDeserializationCluster : public DeserializationCluster {
+ public:
+  ContextDeserializationCluster() { }
+  virtual ~ContextDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      intptr_t length = d->Read<intptr_t>();
+      d->AssignRef(AllocateUninitialized(old_space,
+                                         Context::InstanceSize(length)));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawContext* context = reinterpret_cast<RawContext*>(d->Ref(id));
+      intptr_t length = d->Read<intptr_t>();
+      Deserializer::InitializeHeader(context, kContextCid,
+                                     Context::InstanceSize(length),
+                                     is_vm_object);
+      context->ptr()->num_variables_ = length;
+      context->ptr()->parent_ = reinterpret_cast<RawContext*>(d->ReadRef());
+      for (intptr_t j = 0; j < length; j++) {
+        context->ptr()->data()[j] = d->ReadRef();
+      }
+    }
+  }
+};
+
+class ContextScopeSerializationCluster : public SerializationCluster {
+ public:
+  ContextScopeSerializationCluster() { }
+  virtual ~ContextScopeSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawContextScope* scope = ContextScope::RawCast(object);
+    objects_.Add(scope);
+
+    intptr_t length = scope->ptr()->num_variables_;
+    RawObject** from = scope->from();
+    RawObject** to = scope->to(length);
+    for (RawObject** p = from; p <= to; p++) {
+      s->Push(*p);
+    }
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kContextScopeCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawContextScope* scope = objects_[i];
+      intptr_t length = scope->ptr()->num_variables_;
+      s->Write<intptr_t>(length);
+      s->AssignRef(scope);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawContextScope* scope = objects_[i];
+      intptr_t length = scope->ptr()->num_variables_;
+      s->Write<intptr_t>(length);
+      s->Write<bool>(scope->ptr()->is_implicit_);
+      RawObject** from = scope->from();
+      RawObject** to = scope->to(length);
+      for (RawObject** p = from; p <= to; p++) {
+        s->WriteRef(*p);
+      }
+    }
+  }
+
+ private:
+  GrowableArray<RawContextScope*> objects_;
+};
+
+class ContextScopeDeserializationCluster : public DeserializationCluster {
+ public:
+  ContextScopeDeserializationCluster() { }
+  virtual ~ContextScopeDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      intptr_t length = d->Read<intptr_t>();
+      d->AssignRef(AllocateUninitialized(old_space,
+                                         ContextScope::InstanceSize(length)));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawContextScope* scope = reinterpret_cast<RawContextScope*>(d->Ref(id));
+      intptr_t length = d->Read<intptr_t>();
+      Deserializer::InitializeHeader(scope, kContextScopeCid,
+                                     ContextScope::InstanceSize(length),
+                                     is_vm_object);
+      scope->ptr()->num_variables_ = length;
+      scope->ptr()->is_implicit_ = d->Read<bool>();
+      RawObject** from = scope->from();
+      RawObject** to = scope->to(length);
+      for (RawObject** p = from; p <= to; p++) {
+        *p = d->ReadRef();
+      }
+    }
+  }
+};
+
+
+class ICDataSerializationCluster : public SerializationCluster {
+ public:
+  ICDataSerializationCluster() { }
+  virtual ~ICDataSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawICData* ic = ICData::RawCast(object);
+    objects_.Add(ic);
+
+    RawObject** from = ic->from();
+    RawObject** to = ic->to_snapshot(s->kind());
+    for (RawObject** p = from; p <= to; p++) {
+      s->Push(*p);
+    }
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kICDataCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawICData* ic = objects_[i];
+      s->AssignRef(ic);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    Snapshot::Kind kind = s->kind();
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawICData* ic = objects_[i];
+      RawObject** from = ic->from();
+      RawObject** to = ic->to_snapshot(kind);
+      for (RawObject** p = from; p <= to; p++) {
+        s->WriteRef(*p);
+      }
+      s->Write<int32_t>(ic->ptr()->deopt_id_);
+      s->Write<uint32_t>(ic->ptr()->state_bits_);
+#if defined(TAG_IC_DATA)
+      s->Write<intptr_t>(ic->ptr()->tag_);
+#endif
+    }
+  }
+
+ private:
+  GrowableArray<RawICData*> objects_;
+};
+
+class ICDataDeserializationCluster : public DeserializationCluster {
+ public:
+  ICDataDeserializationCluster() { }
+  virtual ~ICDataDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space, ICData::InstanceSize()));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    Snapshot::Kind kind = d->kind();
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawICData* ic = reinterpret_cast<RawICData*>(d->Ref(id));
+      Deserializer::InitializeHeader(ic, kICDataCid,
+                                     ICData::InstanceSize(), is_vm_object);
+      RawObject** from = ic->from();
+      RawObject** to_snapshot = ic->to_snapshot(kind);
+      RawObject** to = ic->to();
+      for (RawObject** p = from; p <= to_snapshot; p++) {
+        *p = d->ReadRef();
+      }
+      for (RawObject** p = to_snapshot + 1; p <= to; p++) {
+        *p = Object::null();
+      }
+      ic->ptr()->deopt_id_ = d->Read<int32_t>();
+      ic->ptr()->state_bits_ = d->Read<int32_t>();
+#if defined(TAG_IC_DATA)
+      ic->ptr()->tag_ = d->Read<intptr_t>();
+#endif
+    }
+  }
+
+  void PostLoad(const Array& refs, Snapshot::Kind kind, Zone* zone) {
+    NOT_IN_PRODUCT(TimelineDurationScope tds(Thread::Current(),
+        Timeline::GetIsolateStream(), "PostLoadICData"));
+
+    if (kind == Snapshot::kAppNoJIT) {
+      ICData& ic = ICData::Handle(zone);
+      Object& funcOrCode = Object::Handle(zone);
+      Code& code = Code::Handle(zone);
+      Smi& entry_point = Smi::Handle(zone);
+      for (intptr_t i = start_index_; i < stop_index_; i++) {
+        ic ^= refs.At(i);
+        for (intptr_t j = 0; j < ic.NumberOfChecks(); j++) {
+          funcOrCode = ic.GetTargetOrCodeAt(j);
+          if (funcOrCode.IsCode()) {
+            code ^= funcOrCode.raw();
+            entry_point = Smi::FromAlignedAddress(code.EntryPoint());
+            ic.SetEntryPointAt(j, entry_point);
+          }
+        }
+      }
+    }
+  }
+};
+
+class MegamorphicCacheSerializationCluster : public SerializationCluster {
+ public:
+  MegamorphicCacheSerializationCluster() { }
+  virtual ~MegamorphicCacheSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawMegamorphicCache* cache = MegamorphicCache::RawCast(object);
+    objects_.Add(cache);
+
+    RawObject** from = cache->from();
+    RawObject** to = cache->to();
+    for (RawObject** p = from; p <= to; p++) {
+      s->Push(*p);
+    }
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kMegamorphicCacheCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawMegamorphicCache* cache = objects_[i];
+      s->AssignRef(cache);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawMegamorphicCache* cache = objects_[i];
+      RawObject** from = cache->from();
+      RawObject** to = cache->to();
+      for (RawObject** p = from; p <= to; p++) {
+        s->WriteRef(*p);
+      }
+      s->Write<int32_t>(cache->ptr()->filled_entry_count_);
+    }
+  }
+
+ private:
+  GrowableArray<RawMegamorphicCache*> objects_;
+};
+
+
+class MegamorphicCacheDeserializationCluster : public DeserializationCluster {
+ public:
+  MegamorphicCacheDeserializationCluster() { }
+  virtual ~MegamorphicCacheDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space,
+                                         MegamorphicCache::InstanceSize()));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawMegamorphicCache* cache =
+            reinterpret_cast<RawMegamorphicCache*>(d->Ref(id));
+      Deserializer::InitializeHeader(cache, kMegamorphicCacheCid,
+                                     MegamorphicCache::InstanceSize(),
+                                     is_vm_object);
+      RawObject** from = cache->from();
+      RawObject** to = cache->to();
+      for (RawObject** p = from; p <= to; p++) {
+        *p = d->ReadRef();
+      }
+      cache->ptr()->filled_entry_count_ = d->Read<int32_t>();
+    }
+  }
+};
+
+
+class SubtypeTestCacheSerializationCluster : public SerializationCluster {
+ public:
+  SubtypeTestCacheSerializationCluster() { }
+  virtual ~SubtypeTestCacheSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawSubtypeTestCache* cache = SubtypeTestCache::RawCast(object);
+    objects_.Add(cache);
+    s->Push(cache->ptr()->cache_);
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kSubtypeTestCacheCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawSubtypeTestCache* cache = objects_[i];
+      s->AssignRef(cache);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawSubtypeTestCache* cache = objects_[i];
+      s->WriteRef(cache->ptr()->cache_);
+    }
+  }
+
+ private:
+  GrowableArray<RawSubtypeTestCache*> objects_;
+};
+
+class SubtypeTestCacheDeserializationCluster : public DeserializationCluster {
+ public:
+  SubtypeTestCacheDeserializationCluster() { }
+  virtual ~SubtypeTestCacheDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space,
+                                         SubtypeTestCache::InstanceSize()));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawSubtypeTestCache* cache =
+          reinterpret_cast<RawSubtypeTestCache*>(d->Ref(id));
+      Deserializer::InitializeHeader(cache, kSubtypeTestCacheCid,
+                                     SubtypeTestCache::InstanceSize(),
+                                     is_vm_object);
+      cache->ptr()->cache_ = reinterpret_cast<RawArray*>(d->ReadRef());
+    }
+  }
+};
+
+class LanguageErrorSerializationCluster : public SerializationCluster {
+ public:
+  LanguageErrorSerializationCluster() { }
+  virtual ~LanguageErrorSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawLanguageError* error = LanguageError::RawCast(object);
+    objects_.Add(error);
+
+    RawObject** from = error->from();
+    RawObject** to = error->to();
+    for (RawObject** p = from; p <= to; p++) {
+      s->Push(*p);
+    }
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kLanguageErrorCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawLanguageError* error = objects_[i];
+      s->AssignRef(error);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawLanguageError* error = objects_[i];
+      RawObject** from = error->from();
+      RawObject** to = error->to();
+      for (RawObject** p = from; p <= to; p++) {
+        s->WriteRef(*p);
+      }
+      s->WriteTokenPosition(error->ptr()->token_pos_);
+      s->Write<bool>(error->ptr()->report_after_token_);
+      s->Write<int8_t>(error->ptr()->kind_);
+    }
+  }
+
+ private:
+  GrowableArray<RawLanguageError*> objects_;
+};
+
+class LanguageErrorDeserializationCluster : public DeserializationCluster {
+ public:
+  LanguageErrorDeserializationCluster() { }
+  virtual ~LanguageErrorDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space,
+                                         LanguageError::InstanceSize()));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawLanguageError* error = reinterpret_cast<RawLanguageError*>(d->Ref(id));
+      Deserializer::InitializeHeader(error, kLanguageErrorCid,
+                                     LanguageError::InstanceSize(),
+                                     is_vm_object);
+      RawObject** from = error->from();
+      RawObject** to = error->to();
+      for (RawObject** p = from; p <= to; p++) {
+        *p = d->ReadRef();
+      }
+      error->ptr()->token_pos_ = d->ReadTokenPosition();
+      error->ptr()->report_after_token_ = d->Read<bool>();
+      error->ptr()->kind_ = d->Read<int8_t>();
+    }
+  }
+};
+
+class UnhandledExceptionSerializationCluster : public SerializationCluster {
+ public:
+  UnhandledExceptionSerializationCluster() { }
+  virtual ~UnhandledExceptionSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawUnhandledException* exception = UnhandledException::RawCast(object);
+    objects_.Add(exception);
+
+    RawObject** from = exception->from();
+    RawObject** to = exception->to();
+    for (RawObject** p = from; p <= to; p++) {
+      s->Push(*p);
+    }
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kUnhandledExceptionCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawUnhandledException* exception = objects_[i];
+      s->AssignRef(exception);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawUnhandledException* exception = objects_[i];
+      RawObject** from = exception->from();
+      RawObject** to = exception->to();
+      for (RawObject** p = from; p <= to; p++) {
+        s->WriteRef(*p);
+      }
+    }
+  }
+
+ private:
+  GrowableArray<RawUnhandledException*> objects_;
+};
+
+class UnhandledExceptionDeserializationCluster : public DeserializationCluster {
+ public:
+  UnhandledExceptionDeserializationCluster() { }
+  virtual ~UnhandledExceptionDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space,
+                                         UnhandledException::InstanceSize()));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawUnhandledException* exception =
+          reinterpret_cast<RawUnhandledException*>(d->Ref(id));
+      Deserializer::InitializeHeader(exception, kUnhandledExceptionCid,
+                                     UnhandledException::InstanceSize(),
+                                     is_vm_object);
+      RawObject** from = exception->from();
+      RawObject** to = exception->to();
+      for (RawObject** p = from; p <= to; p++) {
+        *p = d->ReadRef();
+      }
+    }
+  }
+};
+
+class InstanceSerializationCluster : public SerializationCluster {
+ public:
+  explicit InstanceSerializationCluster(intptr_t cid) : cid_(cid) {
+    RawClass* cls = Isolate::Current()->class_table()->At(cid);
+    next_field_offset_ =
+        cls->ptr()->next_field_offset_in_words_ << kWordSizeLog2;
+    instance_size_in_words_ = cls->ptr()->instance_size_in_words_;
+    ASSERT(next_field_offset_ > 0);
+    ASSERT(instance_size_in_words_ > 0);
+  }
+  virtual ~InstanceSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawInstance* instance = Instance::RawCast(object);
+    objects_.Add(instance);
+
+    intptr_t offset = Instance::NextFieldOffset();
+    while (offset < next_field_offset_) {
+      RawObject* raw_obj = *reinterpret_cast<RawObject**>(
+          reinterpret_cast<uword>(instance->ptr()) + offset);
+      s->Push(raw_obj);
+      offset += kWordSize;
+    }
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->Write<intptr_t>(cid_);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+
+    s->Write<intptr_t>(next_field_offset_);
+    s->Write<intptr_t>(instance_size_in_words_);
+
+    for (intptr_t i = 0; i < count; i++) {
+      RawInstance* instance = objects_[i];
+      s->AssignRef(instance);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawInstance* instance = objects_[i];
+      s->Write<bool>(instance->IsCanonical());
+      intptr_t offset = Instance::NextFieldOffset();
+      while (offset < next_field_offset_) {
+        RawObject* raw_obj = *reinterpret_cast<RawObject**>(
+            reinterpret_cast<uword>(instance->ptr()) + offset);
+        s->WriteRef(raw_obj);
+        offset += kWordSize;
+      }
+    }
+  }
+
+ private:
+  const intptr_t cid_;
+  intptr_t next_field_offset_;
+  intptr_t instance_size_in_words_;
+  GrowableArray<RawInstance*> objects_;
+};
+
+class InstanceDeserializationCluster : public DeserializationCluster {
+ public:
+  explicit InstanceDeserializationCluster(intptr_t cid) : cid_(cid) { }
+  virtual ~InstanceDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    next_field_offset_  = d->Read<intptr_t>();
+    instance_size_in_words_  = d->Read<intptr_t>();
+    intptr_t instance_size =
+        Object::RoundedAllocationSize(instance_size_in_words_ * kWordSize);
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space, instance_size));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    intptr_t instance_size =
+        Object::RoundedAllocationSize(instance_size_in_words_ * kWordSize);
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawInstance* instance = reinterpret_cast<RawInstance*>(d->Ref(id));
+      bool is_canonical = d->Read<bool>();
+      Deserializer::InitializeHeader(instance, cid_,
+                                     instance_size,
+                                     is_vm_object, is_canonical);
+      intptr_t offset = Instance::NextFieldOffset();
+      while (offset < next_field_offset_) {
+        RawObject** p = reinterpret_cast<RawObject**>(
+            reinterpret_cast<uword>(instance->ptr()) + offset);
+        *p = d->ReadRef();
+        offset += kWordSize;
+      }
+      if (offset < instance_size) {
+        RawObject** p = reinterpret_cast<RawObject**>(
+            reinterpret_cast<uword>(instance->ptr()) + offset);
+        *p = Object::null();
+        offset += kWordSize;
+      }
+      ASSERT(offset == instance_size);
+    }
+  }
+
+ private:
+  const intptr_t cid_;
+  intptr_t next_field_offset_;
+  intptr_t instance_size_in_words_;
+};
+
+class LibraryPrefixSerializationCluster : public SerializationCluster {
+ public:
+  LibraryPrefixSerializationCluster() { }
+  virtual ~LibraryPrefixSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawLibraryPrefix* prefix = LibraryPrefix::RawCast(object);
+    objects_.Add(prefix);
+
+    RawObject** from = prefix->from();
+    RawObject** to = prefix->to();
+    for (RawObject** p = from; p <= to; p++) {
+      s->Push(*p);
+    }
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kLibraryPrefixCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawLibraryPrefix* prefix = objects_[i];
+      s->AssignRef(prefix);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawLibraryPrefix* prefix = objects_[i];
+      RawObject** from = prefix->from();
+      RawObject** to = prefix->to();
+      for (RawObject** p = from; p <= to; p++) {
+        s->WriteRef(*p);
+      }
+      s->Write<uint16_t>(prefix->ptr()->num_imports_);
+      s->Write<bool>(prefix->ptr()->is_deferred_load_);
+      s->Write<bool>(prefix->ptr()->is_loaded_);
+    }
+  }
+
+ private:
+  GrowableArray<RawLibraryPrefix*> objects_;
+};
+
+class LibraryPrefixDeserializationCluster : public DeserializationCluster {
+ public:
+  LibraryPrefixDeserializationCluster() { }
+  virtual ~LibraryPrefixDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space,
+                                         LibraryPrefix::InstanceSize()));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawLibraryPrefix* prefix =
+          reinterpret_cast<RawLibraryPrefix*>(d->Ref(id));
+      Deserializer::InitializeHeader(prefix, kLibraryPrefixCid,
+                                     LibraryPrefix::InstanceSize(),
+                                     is_vm_object);
+      RawObject** from = prefix->from();
+      RawObject** to = prefix->to();
+      for (RawObject** p = from; p <= to; p++) {
+        *p = d->ReadRef();
+      }
+      prefix->ptr()->num_imports_ = d->Read<uint16_t>();
+      prefix->ptr()->is_deferred_load_ = d->Read<bool>();
+      prefix->ptr()->is_loaded_ = d->Read<bool>();
+    }
+  }
+};
+
+class TypeSerializationCluster : public SerializationCluster {
+ public:
+  TypeSerializationCluster() { }
+  virtual ~TypeSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawType* type = Type::RawCast(object);
+    if (type->IsCanonical()) {
+      canonical_objects_.Add(type);
+    } else {
+      objects_.Add(type);
+    }
+
+    RawObject** from = type->from();
+    RawObject** to = type->to();
+    for (RawObject** p = from; p <= to; p++) {
+      s->Push(*p);
+    }
+
+    RawSmi* raw_type_class_id = Smi::RawCast(type->ptr()->type_class_id_);
+    RawClass* type_class =
+        s->isolate()->class_table()->At(Smi::Value(raw_type_class_id));
+    s->Push(type_class);
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kTypeCid);
+    intptr_t count = canonical_objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawType* type = canonical_objects_[i];
+      s->AssignRef(type);
+    }
+    count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawType* type = objects_[i];
+      s->AssignRef(type);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = canonical_objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawType* type = canonical_objects_[i];
+      RawObject** from = type->from();
+      RawObject** to = type->to();
+      for (RawObject** p = from; p <= to; p++) {
+        s->WriteRef(*p);
+      }
+      s->WriteTokenPosition(type->ptr()->token_pos_);
+      s->Write<int8_t>(type->ptr()->type_state_);
+    }
+    count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawType* type = objects_[i];
+      RawObject** from = type->from();
+      RawObject** to = type->to();
+      for (RawObject** p = from; p <= to; p++) {
+        s->WriteRef(*p);
+      }
+      s->WriteTokenPosition(type->ptr()->token_pos_);
+      s->Write<int8_t>(type->ptr()->type_state_);
+    }
+  }
+
+ private:
+  GrowableArray<RawType*> canonical_objects_;
+  GrowableArray<RawType*> objects_;
+};
+
+class TypeDeserializationCluster : public DeserializationCluster {
+ public:
+  TypeDeserializationCluster() { }
+  virtual ~TypeDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    canonical_start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space, Type::InstanceSize()));
+    }
+    canonical_stop_index_ = d->next_index();
+
+    start_index_ = d->next_index();
+    count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space, Type::InstanceSize()));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = canonical_start_index_;
+         id < canonical_stop_index_;
+         id++) {
+      RawType* type = reinterpret_cast<RawType*>(d->Ref(id));
+      Deserializer::InitializeHeader(type, kTypeCid,
+                                     Type::InstanceSize(), is_vm_object, true);
+      RawObject** from = type->from();
+      RawObject** to = type->to();
+      for (RawObject** p = from; p <= to; p++) {
+        *p = d->ReadRef();
+      }
+      type->ptr()->token_pos_ = d->ReadTokenPosition();
+      type->ptr()->type_state_ = d->Read<int8_t>();
+    }
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawType* type = reinterpret_cast<RawType*>(d->Ref(id));
+      Deserializer::InitializeHeader(type, kTypeCid,
+                                     Type::InstanceSize(), is_vm_object);
+      RawObject** from = type->from();
+      RawObject** to = type->to();
+      for (RawObject** p = from; p <= to; p++) {
+        *p = d->ReadRef();
+      }
+      type->ptr()->token_pos_ = d->ReadTokenPosition();
+      type->ptr()->type_state_ = d->Read<int8_t>();
+    }
+  }
+
+ private:
+  intptr_t canonical_start_index_;
+  intptr_t canonical_stop_index_;
+};
+
+class TypeRefSerializationCluster : public SerializationCluster {
+ public:
+  TypeRefSerializationCluster() { }
+  virtual ~TypeRefSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawTypeRef* type = TypeRef::RawCast(object);
+    objects_.Add(type);
+
+    RawObject** from = type->from();
+    RawObject** to = type->to();
+    for (RawObject** p = from; p <= to; p++) {
+      s->Push(*p);
+    }
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kTypeRefCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawTypeRef* type = objects_[i];
+      s->AssignRef(type);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawTypeRef* type = objects_[i];
+      RawObject** from = type->from();
+      RawObject** to = type->to();
+      for (RawObject** p = from; p <= to; p++) {
+        s->WriteRef(*p);
+      }
+    }
+  }
+
+ private:
+  GrowableArray<RawTypeRef*> objects_;
+};
+
+class TypeRefDeserializationCluster : public DeserializationCluster {
+ public:
+  TypeRefDeserializationCluster() { }
+  virtual ~TypeRefDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space, TypeRef::InstanceSize()));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawTypeRef* type = reinterpret_cast<RawTypeRef*>(d->Ref(id));
+      Deserializer::InitializeHeader(type, kTypeRefCid,
+                                     TypeRef::InstanceSize(), is_vm_object);
+      RawObject** from = type->from();
+      RawObject** to = type->to();
+      for (RawObject** p = from; p <= to; p++) {
+        *p = d->ReadRef();
+      }
+    }
+  }
+};
+
+class TypeParameterSerializationCluster : public SerializationCluster {
+ public:
+  TypeParameterSerializationCluster() { }
+  virtual ~TypeParameterSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawTypeParameter* type = TypeParameter::RawCast(object);
+    objects_.Add(type);
+    ASSERT(!type->IsCanonical());
+
+    RawObject** from = type->from();
+    RawObject** to = type->to();
+    for (RawObject** p = from; p <= to; p++) {
+      s->Push(*p);
+    }
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kTypeParameterCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawTypeParameter* type = objects_[i];
+      s->AssignRef(type);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawTypeParameter* type = objects_[i];
+      RawObject** from = type->from();
+      RawObject** to = type->to();
+      for (RawObject** p = from; p <= to; p++) {
+        s->WriteRef(*p);
+      }
+      s->Write<intptr_t>(type->ptr()->parameterized_class_id_);
+      s->WriteTokenPosition(type->ptr()->token_pos_);
+      s->Write<int16_t>(type->ptr()->index_);
+      s->Write<int8_t>(type->ptr()->type_state_);
+    }
+  }
+
+ private:
+  GrowableArray<RawTypeParameter*> objects_;
+};
+
+
+class TypeParameterDeserializationCluster : public DeserializationCluster {
+ public:
+  TypeParameterDeserializationCluster() { }
+  virtual ~TypeParameterDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space,
+                                         TypeParameter::InstanceSize()));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawTypeParameter* type = reinterpret_cast<RawTypeParameter*>(d->Ref(id));
+      Deserializer::InitializeHeader(type, kTypeParameterCid,
+                                     TypeParameter::InstanceSize(),
+                                     is_vm_object);
+      RawObject** from = type->from();
+      RawObject** to = type->to();
+      for (RawObject** p = from; p <= to; p++) {
+        *p = d->ReadRef();
+      }
+      type->ptr()->parameterized_class_id_ = d->Read<intptr_t>();
+      type->ptr()->token_pos_ = d->ReadTokenPosition();
+      type->ptr()->index_ = d->Read<int16_t>();
+      type->ptr()->type_state_ = d->Read<int8_t>();
+    }
+  }
+};
+
+class BoundedTypeSerializationCluster : public SerializationCluster {
+ public:
+  BoundedTypeSerializationCluster() { }
+  virtual ~BoundedTypeSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawBoundedType* type = BoundedType::RawCast(object);
+    objects_.Add(type);
+
+    RawObject** from = type->from();
+    RawObject** to = type->to();
+    for (RawObject** p = from; p <= to; p++) {
+      s->Push(*p);
+    }
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kBoundedTypeCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawBoundedType* type = objects_[i];
+      s->AssignRef(type);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawBoundedType* type = objects_[i];
+      RawObject** from = type->from();
+      RawObject** to = type->to();
+      for (RawObject** p = from; p <= to; p++) {
+        s->WriteRef(*p);
+      }
+    }
+  }
+
+ private:
+  GrowableArray<RawBoundedType*> objects_;
+};
+
+class BoundedTypeDeserializationCluster : public DeserializationCluster {
+ public:
+  BoundedTypeDeserializationCluster() { }
+  virtual ~BoundedTypeDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space,
+                                         BoundedType::InstanceSize()));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawBoundedType* type = reinterpret_cast<RawBoundedType*>(d->Ref(id));
+      Deserializer::InitializeHeader(type, kBoundedTypeCid,
+                                     BoundedType::InstanceSize(), is_vm_object);
+      RawObject** from = type->from();
+      RawObject** to = type->to();
+      for (RawObject** p = from; p <= to; p++) {
+        *p = d->ReadRef();
+      }
+    }
+  }
+};
+
+class ClosureSerializationCluster : public SerializationCluster {
+ public:
+  ClosureSerializationCluster() { }
+  virtual ~ClosureSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawClosure* closure = Closure::RawCast(object);
+    objects_.Add(closure);
+
+    RawObject** from = closure->from();
+    RawObject** to = closure->to();
+    for (RawObject** p = from; p <= to; p++) {
+      s->Push(*p);
+    }
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kClosureCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawClosure* closure = objects_[i];
+      s->AssignRef(closure);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawClosure* closure = objects_[i];
+      s->Write<bool>(closure->IsCanonical());
+      RawObject** from = closure->from();
+      RawObject** to = closure->to();
+      for (RawObject** p = from; p <= to; p++) {
+        s->WriteRef(*p);
+      }
+    }
+  }
+
+ private:
+  GrowableArray<RawClosure*> objects_;
+};
+
+
+class ClosureDeserializationCluster : public DeserializationCluster {
+ public:
+  ClosureDeserializationCluster() { }
+  virtual ~ClosureDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space, Closure::InstanceSize()));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawClosure* closure = reinterpret_cast<RawClosure*>(d->Ref(id));
+      bool is_canonical = d->Read<bool>();
+      Deserializer::InitializeHeader(closure, kClosureCid,
+                                     Closure::InstanceSize(),
+                                     is_vm_object, is_canonical);
+      RawObject** from = closure->from();
+      RawObject** to = closure->to();
+      for (RawObject** p = from; p <= to; p++) {
+        *p = d->ReadRef();
+      }
+    }
+  }
+};
+
+
+class MintSerializationCluster : public SerializationCluster {
+ public:
+  MintSerializationCluster() { }
+  virtual ~MintSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawMint* mint = Mint::RawCast(object);
+    objects_.Add(mint);
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kMintCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawMint* mint = objects_[i];
+      s->AssignRef(mint);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawMint* mint = objects_[i];
+      s->Write<bool>(mint->IsCanonical());
+      s->Write<int64_t>(mint->ptr()->value_);
+    }
+  }
+
+ private:
+  GrowableArray<RawMint*> objects_;
+};
+
+class MintDeserializationCluster : public DeserializationCluster {
+ public:
+  MintDeserializationCluster() { }
+  virtual ~MintDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space, Mint::InstanceSize()));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawMint* mint = reinterpret_cast<RawMint*>(d->Ref(id));
+      bool is_canonical = d->Read<bool>();
+      Deserializer::InitializeHeader(mint, kMintCid,
+                                     Mint::InstanceSize(),
+                                     is_vm_object, is_canonical);
+      mint->ptr()->value_ = d->Read<int64_t>();
+    }
+  }
+};
+
+class BigintSerializationCluster : public SerializationCluster {
+ public:
+  BigintSerializationCluster() { }
+  virtual ~BigintSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawBigint* bigint = Bigint::RawCast(object);
+    objects_.Add(bigint);
+
+    RawObject** from = bigint->from();
+    RawObject** to = bigint->to();
+    for (RawObject** p = from; p <= to; p++) {
+      s->Push(*p);
+    }
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kBigintCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawBigint* bigint = objects_[i];
+      s->AssignRef(bigint);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawBigint* bigint = objects_[i];
+      s->Write<bool>(bigint->IsCanonical());
+      RawObject** from = bigint->from();
+      RawObject** to = bigint->to();
+      for (RawObject** p = from; p <= to; p++) {
+        s->WriteRef(*p);
+      }
+    }
+  }
+
+ private:
+  GrowableArray<RawBigint*> objects_;
+};
+
+class BigintDeserializationCluster : public DeserializationCluster {
+ public:
+  BigintDeserializationCluster() { }
+  virtual ~BigintDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space, Bigint::InstanceSize()));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawBigint* bigint = reinterpret_cast<RawBigint*>(d->Ref(id));
+      bool is_canonical = d->Read<bool>();
+      Deserializer::InitializeHeader(bigint, kBigintCid,
+                                     Bigint::InstanceSize(),
+                                     is_vm_object, is_canonical);
+      RawObject** from = bigint->from();
+      RawObject** to = bigint->to();
+      for (RawObject** p = from; p <= to; p++) {
+        *p = d->ReadRef();
+      }
+    }
+  }
+};
+
+class DoubleSerializationCluster : public SerializationCluster {
+ public:
+  DoubleSerializationCluster() { }
+  virtual ~DoubleSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawDouble* dbl = Double::RawCast(object);
+    objects_.Add(dbl);
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kDoubleCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawDouble* dbl = objects_[i];
+      s->AssignRef(dbl);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawDouble* dbl = objects_[i];
+      s->Write<bool>(dbl->IsCanonical());
+      s->Write<double>(dbl->ptr()->value_);
+    }
+  }
+
+ private:
+  GrowableArray<RawDouble*> objects_;
+};
+
+class DoubleDeserializationCluster : public DeserializationCluster {
+ public:
+  DoubleDeserializationCluster() { }
+  virtual ~DoubleDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space, Double::InstanceSize()));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawDouble* dbl = reinterpret_cast<RawDouble*>(d->Ref(id));
+      bool is_canonical = d->Read<bool>();
+      Deserializer::InitializeHeader(dbl, kDoubleCid,
+                                     Double::InstanceSize(),
+                                     is_vm_object, is_canonical);
+      dbl->ptr()->value_ = d->Read<double>();
+    }
+  }
+};
+
+
+class GrowableObjectArraySerializationCluster : public SerializationCluster {
+ public:
+  GrowableObjectArraySerializationCluster() { }
+  virtual ~GrowableObjectArraySerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawGrowableObjectArray* array = GrowableObjectArray::RawCast(object);
+    objects_.Add(array);
+
+    RawObject** from = array->from();
+    RawObject** to = array->to();
+    for (RawObject** p = from; p <= to; p++) {
+      s->Push(*p);
+    }
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kGrowableObjectArrayCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawGrowableObjectArray* array = objects_[i];
+      s->AssignRef(array);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawGrowableObjectArray* array = objects_[i];
+      s->Write<bool>(array->IsCanonical());
+      RawObject** from = array->from();
+      RawObject** to = array->to();
+      for (RawObject** p = from; p <= to; p++) {
+        s->WriteRef(*p);
+      }
+    }
+  }
+
+ private:
+  GrowableArray<RawGrowableObjectArray*> objects_;
+};
+
+class GrowableObjectArrayDeserializationCluster
+    : public DeserializationCluster {
+ public:
+  GrowableObjectArrayDeserializationCluster() { }
+  virtual ~GrowableObjectArrayDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space,
+                                         GrowableObjectArray::InstanceSize()));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawGrowableObjectArray* list =
+          reinterpret_cast<RawGrowableObjectArray*>(d->Ref(id));
+      bool is_canonical = d->Read<bool>();
+      Deserializer::InitializeHeader(list, kGrowableObjectArrayCid,
+                                     GrowableObjectArray::InstanceSize(),
+                                     is_vm_object, is_canonical);
+      RawObject** from = list->from();
+      RawObject** to = list->to();
+      for (RawObject** p = from; p <= to; p++) {
+        *p = d->ReadRef();
+      }
+    }
+  }
+};
+
+class TypedDataSerializationCluster : public SerializationCluster {
+ public:
+  explicit TypedDataSerializationCluster(intptr_t cid) : cid_(cid) { }
+  virtual ~TypedDataSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawTypedData* data = TypedData::RawCast(object);
+    objects_.Add(data);
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->Write<intptr_t>(cid_);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawTypedData* data = objects_[i];
+      intptr_t length = Smi::Value(data->ptr()->length_);
+      s->Write<intptr_t>(length);
+      s->AssignRef(data);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    intptr_t element_size = TypedData::ElementSizeInBytes(cid_);
+    for (intptr_t i = 0; i < count; i++) {
+      RawTypedData* data = objects_[i];
+      intptr_t length = Smi::Value(data->ptr()->length_);
+      s->Write<intptr_t>(length);
+      s->Write<bool>(data->IsCanonical());
+      uint8_t* cdata = reinterpret_cast<uint8_t*>(data->ptr()->data());
+      s->WriteBytes(cdata, length * element_size);
+    }
+  }
+
+ private:
+  const intptr_t cid_;
+  GrowableArray<RawTypedData*> objects_;
+};
+
+
+class TypedDataDeserializationCluster : public DeserializationCluster {
+ public:
+  explicit TypedDataDeserializationCluster(intptr_t cid) : cid_(cid) { }
+  virtual ~TypedDataDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    intptr_t element_size = TypedData::ElementSizeInBytes(cid_);
+    for (intptr_t i = 0; i < count; i++) {
+      intptr_t length = d->Read<intptr_t>();
+      d->AssignRef(AllocateUninitialized(old_space,
+          TypedData::InstanceSize(length * element_size)));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+    intptr_t element_size = TypedData::ElementSizeInBytes(cid_);
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawTypedData* data = reinterpret_cast<RawTypedData*>(d->Ref(id));
+      intptr_t length = d->Read<intptr_t>();
+      bool is_canonical = d->Read<bool>();
+      intptr_t length_in_bytes = length * element_size;
+      Deserializer::InitializeHeader(data, cid_,
+                                     TypedData::InstanceSize(length_in_bytes),
+                                     is_vm_object, is_canonical);
+      data->ptr()->length_ = Smi::New(length);
+      uint8_t* cdata = reinterpret_cast<uint8_t*>(data->ptr()->data());
+      d->ReadBytes(cdata, length_in_bytes);
+    }
+  }
+
+ private:
+  const intptr_t cid_;
+};
+
+
+class ExternalTypedDataSerializationCluster : public SerializationCluster {
+ public:
+  explicit ExternalTypedDataSerializationCluster(intptr_t cid) : cid_(cid) { }
+  virtual ~ExternalTypedDataSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawExternalTypedData* data = ExternalTypedData::RawCast(object);
+    objects_.Add(data);
+    ASSERT(!data->IsCanonical());
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->Write<intptr_t>(cid_);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawExternalTypedData* data = objects_[i];
+      s->AssignRef(data);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    intptr_t element_size = ExternalTypedData::ElementSizeInBytes(cid_);
+    for (intptr_t i = 0; i < count; i++) {
+      RawExternalTypedData* data = objects_[i];
+      intptr_t length = Smi::Value(data->ptr()->length_);
+      s->Write<intptr_t>(length);
+      uint8_t* cdata = reinterpret_cast<uint8_t*>(data->ptr()->data_);
+      s->WriteBytes(cdata, length * element_size);
+    }
+  }
+
+ private:
+  const intptr_t cid_;
+  GrowableArray<RawExternalTypedData*> objects_;
+};
+
+
+class ExternalTypedDataDeserializationCluster : public DeserializationCluster {
+ public:
+  explicit ExternalTypedDataDeserializationCluster(intptr_t cid) : cid_(cid) { }
+  virtual ~ExternalTypedDataDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space,
+                                         ExternalTypedData::InstanceSize()));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+    intptr_t element_size = ExternalTypedData::ElementSizeInBytes(cid_);
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawExternalTypedData* data =
+          reinterpret_cast<RawExternalTypedData*>(d->Ref(id));
+      intptr_t length = d->Read<intptr_t>();
+      Deserializer::InitializeHeader(data, cid_,
+                                     ExternalTypedData::InstanceSize(),
+                                     is_vm_object);
+      data->ptr()->length_ = Smi::New(length);
+      data->ptr()->data_ = const_cast<uint8_t*>(d->CurrentBufferAddress());
+      d->Advance(length * element_size);
+    }
+  }
+
+ private:
+  const intptr_t cid_;
+};
+
+class StacktraceSerializationCluster : public SerializationCluster {
+ public:
+  StacktraceSerializationCluster() { }
+  virtual ~StacktraceSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawStacktrace* trace = Stacktrace::RawCast(object);
+    objects_.Add(trace);
+
+    RawObject** from = trace->from();
+    RawObject** to = trace->to();
+    for (RawObject** p = from; p <= to; p++) {
+      s->Push(*p);
+    }
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kStacktraceCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawStacktrace* trace = objects_[i];
+      s->AssignRef(trace);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawStacktrace* trace = objects_[i];
+      RawObject** from = trace->from();
+      RawObject** to = trace->to();
+      for (RawObject** p = from; p <= to; p++) {
+        s->WriteRef(*p);
+      }
+    }
+  }
+
+ private:
+  GrowableArray<RawStacktrace*> objects_;
+};
+
+class StacktraceDeserializationCluster : public DeserializationCluster {
+ public:
+  StacktraceDeserializationCluster() { }
+  virtual ~StacktraceDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space,
+                                         Stacktrace::InstanceSize()));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawStacktrace* trace = reinterpret_cast<RawStacktrace*>(d->Ref(id));
+      Deserializer::InitializeHeader(trace, kStacktraceCid,
+                                     Stacktrace::InstanceSize(), is_vm_object);
+      RawObject** from = trace->from();
+      RawObject** to = trace->to();
+      for (RawObject** p = from; p <= to; p++) {
+        *p = d->ReadRef();
+      }
+    }
+  }
+};
+
+class RegExpSerializationCluster : public SerializationCluster {
+ public:
+  RegExpSerializationCluster() { }
+  virtual ~RegExpSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawRegExp* regexp = RegExp::RawCast(object);
+    objects_.Add(regexp);
+
+    RawObject** from = regexp->from();
+    RawObject** to = regexp->to();
+    for (RawObject** p = from; p <= to; p++) {
+      s->Push(*p);
+    }
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kRegExpCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawRegExp* regexp = objects_[i];
+      s->AssignRef(regexp);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawRegExp* regexp = objects_[i];
+      RawObject** from = regexp->from();
+      RawObject** to = regexp->to();
+      for (RawObject** p = from; p <= to; p++) {
+        s->WriteRef(*p);
+      }
+
+      s->Write<intptr_t>(regexp->ptr()->num_registers_);
+      s->Write<int8_t>(regexp->ptr()->type_flags_);
+    }
+  }
+
+ private:
+  GrowableArray<RawRegExp*> objects_;
+};
+
+class RegExpDeserializationCluster : public DeserializationCluster {
+ public:
+  RegExpDeserializationCluster() { }
+  virtual ~RegExpDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space,
+                                         RegExp::InstanceSize()));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawRegExp* regexp = reinterpret_cast<RawRegExp*>(d->Ref(id));
+      Deserializer::InitializeHeader(regexp, kRegExpCid,
+                                     RegExp::InstanceSize(), is_vm_object);
+      RawObject** from = regexp->from();
+      RawObject** to = regexp->to();
+      for (RawObject** p = from; p <= to; p++) {
+        *p = d->ReadRef();
+      }
+
+      regexp->ptr()->num_registers_ = d->Read<intptr_t>();
+      regexp->ptr()->type_flags_ = d->Read<int8_t>();
+    }
+  }
+};
+
+class LinkedHashMapSerializationCluster : public SerializationCluster {
+ public:
+  LinkedHashMapSerializationCluster() { }
+  virtual ~LinkedHashMapSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawLinkedHashMap* map = LinkedHashMap::RawCast(object);
+    objects_.Add(map);
+
+    s->Push(map->ptr()->type_arguments_);
+
+    intptr_t used_data = Smi::Value(map->ptr()->used_data_);
+    RawArray* data_array = map->ptr()->data_;
+    RawObject** data_elements = data_array->ptr()->data();
+    for (intptr_t i = 0; i < used_data; i += 2) {
+      RawObject* key = data_elements[i];
+      if (key != data_array) {
+        RawObject* value = data_elements[i + 1];
+        s->Push(key);
+        s->Push(value);
+      }
+    }
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kLinkedHashMapCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawLinkedHashMap* map = objects_[i];
+      s->AssignRef(map);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawLinkedHashMap* map = objects_[i];
+      s->Write<bool>(map->IsCanonical());
+
+      s->WriteRef(map->ptr()->type_arguments_);
+
+      const intptr_t used_data = Smi::Value(map->ptr()->used_data_);
+      ASSERT((used_data & 1) == 0);  // Keys + values, so must be even.
+      const intptr_t deleted_keys = Smi::Value(map->ptr()->deleted_keys_);
+
+      // Write out the number of (not deleted) key/value pairs that will follow.
+      s->Write<intptr_t>((used_data >> 1) - deleted_keys);
+
+      RawArray* data_array = map->ptr()->data_;
+      RawObject** data_elements = data_array->ptr()->data();
+      for (intptr_t i = 0; i < used_data; i += 2) {
+        RawObject* key = data_elements[i];
+        if (key != data_array) {
+          RawObject* value = data_elements[i + 1];
+          s->WriteRef(key);
+          s->WriteRef(value);
+        }
+      }
+    }
+  }
+
+ private:
+  GrowableArray<RawLinkedHashMap*> objects_;
+};
+
+class LinkedHashMapDeserializationCluster : public DeserializationCluster {
+ public:
+  LinkedHashMapDeserializationCluster() { }
+  virtual ~LinkedHashMapDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      d->AssignRef(AllocateUninitialized(old_space,
+                                         LinkedHashMap::InstanceSize()));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+    PageSpace* old_space = d->heap()->old_space();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawLinkedHashMap* map = reinterpret_cast<RawLinkedHashMap*>(d->Ref(id));
+      bool is_canonical = d->Read<bool>();
+      Deserializer::InitializeHeader(map, kLinkedHashMapCid,
+                                     LinkedHashMap::InstanceSize(),
+                                     is_vm_object, is_canonical);
+
+      map->ptr()->type_arguments_ =
+          reinterpret_cast<RawTypeArguments*>(d->ReadRef());
+
+      // TODO(rmacnak): Reserve ref ids and co-allocate in ReadAlloc.
+      intptr_t pairs = d->Read<intptr_t>();
+      intptr_t used_data = pairs << 1;
+      intptr_t data_size = Utils::Maximum(
+          Utils::RoundUpToPowerOfTwo(used_data),
+          static_cast<uintptr_t>(LinkedHashMap::kInitialIndexSize));
+
+      RawArray* data = reinterpret_cast<RawArray*>(
+          AllocateUninitialized(old_space, Array::InstanceSize(data_size)));
+      data->ptr()->type_arguments_ = TypeArguments::null();
+      data->ptr()->length_ = Smi::New(data_size);
+      intptr_t i;
+      for (i = 0; i < used_data; i++) {
+        data->ptr()->data()[i] = d->ReadRef();
+      }
+      for (; i < data_size; i++) {
+        data->ptr()->data()[i] = Object::null();
+      }
+
+      map->ptr()->index_ = TypedData::null();
+      map->ptr()->hash_mask_ = Smi::New(0);
+      map->ptr()->data_ = data;
+      map->ptr()->used_data_ = Smi::New(used_data);
+      map->ptr()->deleted_keys_ = Smi::New(0);
+    }
+  }
+};
+
+class ArraySerializationCluster : public SerializationCluster {
+ public:
+  explicit ArraySerializationCluster(intptr_t cid) : cid_(cid) { }
+  virtual ~ArraySerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawArray* array = Array::RawCast(object);
+    objects_.Add(array);
+
+    s->Push(array->ptr()->type_arguments_);
+    intptr_t length = Smi::Value(array->ptr()->length_);
+    for (intptr_t i = 0; i < length; i++) {
+      s->Push(array->ptr()->data()[i]);
+    }
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(cid_);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawArray* array = objects_[i];
+      intptr_t length = Smi::Value(array->ptr()->length_);
+      s->Write<intptr_t>(length);
+      s->AssignRef(array);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawArray* array = objects_[i];
+      intptr_t length = Smi::Value(array->ptr()->length_);
+      s->Write<intptr_t>(length);
+      s->Write<bool>(array->IsCanonical());
+      s->WriteRef(array->ptr()->type_arguments_);
+      for (intptr_t j = 0; j < length; j++) {
+        s->WriteRef(array->ptr()->data()[j]);
+      }
+    }
+  }
+
+ private:
+  intptr_t cid_;
+  GrowableArray<RawArray*> objects_;
+};
+
+class ArrayDeserializationCluster : public DeserializationCluster {
+ public:
+  explicit ArrayDeserializationCluster(intptr_t cid) : cid_(cid) { }
+  virtual ~ArrayDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      intptr_t length = d->Read<intptr_t>();
+      d->AssignRef(AllocateUninitialized(old_space,
+                                         Array::InstanceSize(length)));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawArray* array = reinterpret_cast<RawArray*>(d->Ref(id));
+      intptr_t length = d->Read<intptr_t>();
+      bool is_canonical = d->Read<bool>();
+      Deserializer::InitializeHeader(array, cid_,
+                                     Array::InstanceSize(length),
+                                     is_vm_object, is_canonical);
+      array->ptr()->type_arguments_ =
+          reinterpret_cast<RawTypeArguments*>(d->ReadRef());
+      array->ptr()->length_ = Smi::New(length);
+      for (intptr_t j = 0; j < length; j++) {
+        array->ptr()->data()[j] = d->ReadRef();
+      }
+    }
+  }
+
+ private:
+  const intptr_t cid_;
+};
+
+class OneByteStringSerializationCluster : public SerializationCluster {
+ public:
+  OneByteStringSerializationCluster() { }
+  virtual ~OneByteStringSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawOneByteString* str = reinterpret_cast<RawOneByteString*>(object);
+    objects_.Add(str);
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kOneByteStringCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawOneByteString* str = objects_[i];
+      intptr_t length = Smi::Value(str->ptr()->length_);
+      s->Write<intptr_t>(length);
+      s->AssignRef(str);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawOneByteString* str = objects_[i];
+      intptr_t length = Smi::Value(str->ptr()->length_);
+      s->Write<intptr_t>(length);
+      s->Write<bool>(str->IsCanonical());
+      intptr_t hash = Smi::Value(str->ptr()->hash_);
+      s->Write<int32_t>(hash);
+      s->WriteBytes(str->ptr()->data(), length);
+    }
+  }
+
+ private:
+  GrowableArray<RawOneByteString*> objects_;
+};
+
+class OneByteStringDeserializationCluster : public DeserializationCluster {
+ public:
+  OneByteStringDeserializationCluster() { }
+  virtual ~OneByteStringDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      intptr_t length = d->Read<intptr_t>();
+      d->AssignRef(AllocateUninitialized(old_space,
+                                         OneByteString::InstanceSize(length)));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawOneByteString* str = reinterpret_cast<RawOneByteString*>(d->Ref(id));
+      intptr_t length = d->Read<intptr_t>();
+      bool is_canonical = d->Read<bool>();
+      Deserializer::InitializeHeader(str, kOneByteStringCid,
+                                     OneByteString::InstanceSize(length),
+                                     is_vm_object, is_canonical);
+      str->ptr()->length_ = Smi::New(length);
+      str->ptr()->hash_ = Smi::New(d->Read<intptr_t>());
+      for (intptr_t j = 0; j < length; j++) {
+        str->ptr()->data()[j] = d->Read<uint8_t>();
+      }
+    }
+  }
+};
+
+class TwoByteStringSerializationCluster : public SerializationCluster {
+ public:
+  TwoByteStringSerializationCluster() { }
+  virtual ~TwoByteStringSerializationCluster() { }
+
+  void Trace(Serializer* s, RawObject* object) {
+    RawTwoByteString* str = reinterpret_cast<RawTwoByteString*>(object);
+    objects_.Add(str);
+  }
+
+  void WriteAlloc(Serializer* s) {
+    s->WriteCid(kTwoByteStringCid);
+    intptr_t count = objects_.length();
+    s->Write<intptr_t>(count);
+    for (intptr_t i = 0; i < count; i++) {
+      RawTwoByteString* str = objects_[i];
+      intptr_t length = Smi::Value(str->ptr()->length_);
+      s->Write<intptr_t>(length);
+      s->AssignRef(str);
+    }
+  }
+
+  void WriteFill(Serializer* s) {
+    intptr_t count = objects_.length();
+    for (intptr_t i = 0; i < count; i++) {
+      RawTwoByteString* str = objects_[i];
+      intptr_t length = Smi::Value(str->ptr()->length_);
+      s->Write<intptr_t>(length);
+      s->Write<bool>(str->IsCanonical());
+      intptr_t hash = Smi::Value(str->ptr()->hash_);
+      s->Write<int32_t>(hash);
+      s->WriteBytes(reinterpret_cast<uint8_t*>(str->ptr()->data()), length * 2);
+    }
+  }
+
+ private:
+  GrowableArray<RawTwoByteString*> objects_;
+};
+
+class TwoByteStringDeserializationCluster : public DeserializationCluster {
+ public:
+  TwoByteStringDeserializationCluster() { }
+  virtual ~TwoByteStringDeserializationCluster() { }
+
+  void ReadAlloc(Deserializer* d) {
+    start_index_ = d->next_index();
+    PageSpace* old_space = d->heap()->old_space();
+    intptr_t count = d->Read<intptr_t>();
+    for (intptr_t i = 0; i < count; i++) {
+      intptr_t length = d->Read<intptr_t>();
+      d->AssignRef(AllocateUninitialized(old_space,
+                                         TwoByteString::InstanceSize(length)));
+    }
+    stop_index_ = d->next_index();
+  }
+
+  void ReadFill(Deserializer* d) {
+    bool is_vm_object = d->isolate() == Dart::vm_isolate();
+
+    for (intptr_t id = start_index_; id < stop_index_; id++) {
+      RawTwoByteString* str =
+          reinterpret_cast<RawTwoByteString*>(d->Ref(id));
+      intptr_t length = d->Read<intptr_t>();
+      bool is_canonical = d->Read<bool>();
+      Deserializer::InitializeHeader(str, kTwoByteStringCid,
+                                     TwoByteString::InstanceSize(length),
+                                     is_vm_object, is_canonical);
+      str->ptr()->length_ = Smi::New(length);
+      str->ptr()->hash_ = Smi::New(d->Read<int32_t>());
+      uint8_t* cdata = reinterpret_cast<uint8_t*>(str->ptr()->data());
+      d->ReadBytes(cdata, length * 2);
+    }
+  }
+};
+
+
+Serializer::Serializer(Thread* thread,
+                       Snapshot::Kind kind,
+                       uint8_t** buffer,
+                       ReAlloc alloc,
+                       intptr_t initial_size,
+                       InstructionsWriter* instructions_writer)
+    : StackResource(thread),
+      heap_(thread->isolate()->heap()),
+      zone_(thread->zone()),
+      kind_(kind),
+      stream_(buffer, alloc, initial_size),
+      instructions_writer_(instructions_writer),
+      clusters_by_cid_(NULL),
+      stack_(),
+      num_cids_(0),
+      num_base_objects_(0),
+      num_written_objects_(0),
+      next_ref_index_(1) {
+  num_cids_ = thread->isolate()->class_table()->NumCids();
+  clusters_by_cid_ = new SerializationCluster*[num_cids_];
+  for (intptr_t i = 0; i < num_cids_; i++) {
+    clusters_by_cid_[i] = NULL;

[siva, 2016/06/30 00:06:07]

why not just call NewClusterForClass(i) here instead of initializing to NULL
wouldn't we encounter all the class ids in a full snapshot anyway?

[rmacnak, 2016/06/30 01:39:21]

We only create a cluster if there are instances of the class included in the
snapshot. For user classes, they would only need a cluster if they have const
instances.

+  }
+}
+
+
+Serializer::~Serializer() {
+  delete[] clusters_by_cid_;
+}
+
+
+SerializationCluster* Serializer::NewClusterForClass(intptr_t cid) {
+  Zone* Z = zone_;
+  if ((cid > kNumPredefinedCids) ||
+      (cid == kInstanceCid) ||
+      RawObject::IsTypedDataViewClassId(cid)) {
+    Push(isolate()->class_table()->At(cid));
+    return new (Z) InstanceSerializationCluster(cid);
+  }
+  if (RawObject::IsExternalTypedDataClassId(cid)) {
+    return new (Z) ExternalTypedDataSerializationCluster(cid);
+  }
+  if (RawObject::IsTypedDataClassId(cid)) {
+    return new (Z) TypedDataSerializationCluster(cid);
+  }
+
+  switch (cid) {
+    case kClassCid: return new (Z) ClassSerializationCluster();
+    case kUnresolvedClassCid:
+      return new (Z) UnresolvedClassSerializationCluster();
+    case kTypeArgumentsCid: return new (Z) TypeArgumentsSerializationCluster();
+    case kPatchClassCid: return new (Z) PatchClassSerializationCluster();
+    case kFunctionCid: return new (Z) FunctionSerializationCluster();
+    case kClosureDataCid: return new (Z) ClosureDataSerializationCluster();
+    case kRedirectionDataCid:
+      return new (Z) RedirectionDataSerializationCluster();
+    case kFieldCid: return new (Z) FieldSerializationCluster();
+    case kLiteralTokenCid: return new (Z) LiteralTokenSerializationCluster();
+    case kTokenStreamCid: return new (Z) TokenStreamSerializationCluster();
+    case kScriptCid: return new (Z) ScriptSerializationCluster();
+    case kLibraryCid: return new (Z) LibrarySerializationCluster();
+    case kNamespaceCid: return new (Z) NamespaceSerializationCluster();
+    case kCodeCid: return new (Z) CodeSerializationCluster();
+    case kObjectPoolCid: return new (Z) ObjectPoolSerializationCluster();
+    case kPcDescriptorsCid:
+      return new (Z) RODataSerializationCluster(kPcDescriptorsCid);
+    case kStackmapCid:
+      return new (Z) RODataSerializationCluster(kStackmapCid);
+    case kExceptionHandlersCid:
+      return new (Z) ExceptionHandlersSerializationCluster();
+    case kContextCid: return new (Z) ContextSerializationCluster();
+    case kContextScopeCid: return new (Z) ContextScopeSerializationCluster();
+    case kICDataCid: return new (Z) ICDataSerializationCluster();
+    case kMegamorphicCacheCid:
+      return new (Z) MegamorphicCacheSerializationCluster();
+    case kSubtypeTestCacheCid:
+      return new (Z) SubtypeTestCacheSerializationCluster();
+    case kLanguageErrorCid:
+      return new (Z) LanguageErrorSerializationCluster();
+    case kUnhandledExceptionCid:
+      return new (Z) UnhandledExceptionSerializationCluster();
+    case kLibraryPrefixCid: return new (Z) LibraryPrefixSerializationCluster();
+    case kTypeCid: return new (Z) TypeSerializationCluster();
+    case kTypeRefCid: return new (Z) TypeRefSerializationCluster();
+    case kTypeParameterCid: return new (Z) TypeParameterSerializationCluster();
+    case kBoundedTypeCid: return new (Z) BoundedTypeSerializationCluster();
+    case kClosureCid: return new (Z) ClosureSerializationCluster();
+    case kMintCid: return new (Z) MintSerializationCluster();
+    case kBigintCid: return new (Z) BigintSerializationCluster();
+    case kDoubleCid: return new (Z) DoubleSerializationCluster();
+    case kGrowableObjectArrayCid:
+      return new (Z) GrowableObjectArraySerializationCluster();
+    case kStacktraceCid: return new (Z) StacktraceSerializationCluster();
+    case kRegExpCid: return new (Z) RegExpSerializationCluster();
+    case kLinkedHashMapCid: return new (Z) LinkedHashMapSerializationCluster();
+    case kArrayCid:
+      return new (Z) ArraySerializationCluster(kArrayCid);
+    case kImmutableArrayCid:
+      return new (Z) ArraySerializationCluster(kImmutableArrayCid);
+    case kOneByteStringCid: {
+      if (Snapshot::IncludesCode(kind_)) {
+        return new (Z) RODataSerializationCluster(kOneByteStringCid);
+      } else {
+        return new (Z) OneByteStringSerializationCluster();
+      }
+    }
+    case kTwoByteStringCid: {
+      if (Snapshot::IncludesCode(kind_)) {
+        return new (Z) RODataSerializationCluster(kTwoByteStringCid);
+      } else {
+        return new (Z) TwoByteStringSerializationCluster();
+      }
+    }
+    default: break;
+  }
+
+  FATAL1("No cluster defined for cid %" Pd, cid);
+  return NULL;
+}
+
+
+void Serializer::Trace(RawObject* object) {
+  intptr_t cid;
+  if (!object->IsHeapObject()) {
+    cid = kSmiCid;
+  } else {
+    cid = object->GetClassId();
+  }
+
+  SerializationCluster* cluster = clusters_by_cid_[cid];
+  if (cluster == NULL) {
+    cluster = NewClusterForClass(cid);
+    clusters_by_cid_[cid] = cluster;
+  }
+  ASSERT(cluster != NULL);
+  cluster->Trace(this, object);
+}
+
+
+void Serializer::WriteVersionAndFeatures() {
+  const char* expected_version = Version::SnapshotString();
+  ASSERT(expected_version != NULL);
+  const intptr_t version_len = strlen(expected_version);
+  WriteBytes(reinterpret_cast<const uint8_t*>(expected_version), version_len);
+
+  const char* expected_features = Dart::FeaturesString(kind_);
+  ASSERT(expected_features != NULL);
+  const intptr_t features_len = strlen(expected_features);
+  WriteBytes(reinterpret_cast<const uint8_t*>(expected_features),
+             features_len + 1);
+  free(const_cast<char*>(expected_features));
+}
+
+
+#if defined(DEBUG)
+static const intptr_t kSectionMarker = 0xABAB;
+#endif
+
+void Serializer::Serialize() {
+  while (stack_.length() > 0) {
+    Trace(stack_.RemoveLast());
+  }
+
+  intptr_t num_clusters = 0;
+  for (intptr_t cid = 1; cid < num_cids_; cid++) {
+    SerializationCluster* cluster = clusters_by_cid_[cid];
+    if (cluster != NULL) {
+      num_clusters++;
+    }
+  }
+
+  intptr_t num_objects = num_base_objects_ + num_written_objects_;
+
+  Write<int32_t>(num_objects);
+  Write<int32_t>(num_clusters);
+
+  for (intptr_t cid = 1; cid < num_cids_; cid++) {
+    SerializationCluster* cluster = clusters_by_cid_[cid];
+    if (cluster != NULL) {
+      cluster->WriteAlloc(this);
+#if defined(DEBUG)
+      Write<intptr_t>(next_ref_index_);
+#endif
+    }
+  }
+
+  // We should have assigned a ref to every object we pushed.
+  ASSERT((next_ref_index_ - 1) == num_objects);
+
+  for (intptr_t cid = 1; cid < num_cids_; cid++) {
+    SerializationCluster* cluster = clusters_by_cid_[cid];
+    if (cluster != NULL) {
+      cluster->WriteFill(this);
+#if defined(DEBUG)
+      Write<intptr_t>(kSectionMarker);
+#endif
+    }
+  }
+}
+
+
+void Serializer::AddVMIsolateBaseObjects() {
+  // These objects are always allocated by Object::InitOnce, so they are not
+  // written into the snapshot.
+
+  AddBaseObject(Object::null());
+  AddBaseObject(Object::sentinel().raw());
+  AddBaseObject(Object::transition_sentinel().raw());
+  AddBaseObject(Object::empty_array().raw());
+  AddBaseObject(Object::zero_array().raw());
+  AddBaseObject(Object::dynamic_type().raw());
+  AddBaseObject(Object::void_type().raw());
+  AddBaseObject(Bool::True().raw());
+  AddBaseObject(Bool::False().raw());
+  AddBaseObject(Object::extractor_parameter_types().raw());
+  AddBaseObject(Object::extractor_parameter_names().raw());
+  AddBaseObject(Object::empty_context_scope().raw());
+  AddBaseObject(Object::empty_descriptors().raw());
+  AddBaseObject(Object::empty_var_descriptors().raw());
+  AddBaseObject(Object::empty_exception_handlers().raw());
+
+  for (intptr_t i = 0; i < ArgumentsDescriptor::kCachedDescriptorCount; i++) {
+    AddBaseObject(ArgumentsDescriptor::cached_args_descriptors_[i]);
+  }
+  for (intptr_t i = 0; i < ICData::kCachedICDataArrayCount; i++) {
+    AddBaseObject(ICData::cached_icdata_arrays_[i]);
+  }
+
+  ClassTable* table = isolate()->class_table();
+  for (intptr_t cid = kClassCid; cid <= kUnwindErrorCid; cid++) {
+    // Error has no class object.
+    if (cid != kErrorCid) {
+      ASSERT(table->HasValidClassAt(cid));
+      AddBaseObject(table->At(cid));
+    }
+  }
+  AddBaseObject(table->At(kDynamicCid));
+  AddBaseObject(table->At(kVoidCid));
+}
+
+
+intptr_t Serializer::WriteVMSnapshot(const Array& symbols,
+                                     const Array& scripts) {
+  NoSafepointScope no_safepoint;
+
+  AddVMIsolateBaseObjects();
+
+  // Push roots.
+  Push(symbols.raw());
+  Push(scripts.raw());
+  if (Snapshot::IncludesCode(kind_)) {
+    StubCode::Push(this);
+  }
+
+  Serialize();
+
+  // Write roots.
+  WriteRef(symbols.raw());
+  WriteRef(scripts.raw());
+  if (Snapshot::IncludesCode(kind_)) {
+    StubCode::WriteRef(this);
+  }
+
+#if defined(DEBUG)
+  Write<intptr_t>(kSectionMarker);
+#endif
+
+  // Note we are not clearing the object id table. The full ref table
+  // of the vm isolate snapshot serves as the base objects for the
+  // regular isolate snapshot.
+
+  // Return the number of objects, -1 accounts for unused ref 0.
+  return next_ref_index_ - 1;
+}
+
+
+void Serializer::WriteFullSnapshot(intptr_t num_base_objects,
+                                   ObjectStore* object_store) {
+  NoSafepointScope no_safepoint;
+
+  if (num_base_objects == 0) {
+    // Units tests not writing a new vm isolate.
+    const Array& base_objects = Object::vm_isolate_snapshot_object_table();
+    for (intptr_t i = 1; i < base_objects.Length(); i++) {
+      AddBaseObject(base_objects.At(i));
+    }
+  } else {
+    // Base objects carried over from WriteVMIsolateSnapshot.
+    num_base_objects_ += num_base_objects;
+    next_ref_index_ += num_base_objects;
+  }
+
+  // Push roots.
+  RawObject** from = object_store->from();
+  RawObject** to = object_store->to_snapshot(kind_);
+  for (RawObject** p = from; p <= to; p++) {
+    Push(*p);
+  }
+
+  Serialize();
+
+  // Write roots.
+  for (RawObject** p = from; p <= to; p++) {
+    WriteRef(*p);
+  }
+
+#if defined(DEBUG)
+  Write<intptr_t>(kSectionMarker);
+#endif
+
+  heap_->ResetObjectIdTable();
+}
+
+
+Deserializer::Deserializer(Thread* thread,
+                           Snapshot::Kind kind,
+                           const uint8_t* buffer,
+                           intptr_t size,
+                           const uint8_t* instructions_buffer,
+                           const uint8_t* data_buffer)
+    : StackResource(thread),
+      heap_(thread->isolate()->heap()),
+      zone_(thread->zone()),
+      kind_(kind),
+      stream_(buffer, size),
+      instructions_reader_(NULL),
+      refs_(NULL),
+      next_ref_index_(1),
+      clusters_(NULL) {
+  if (Snapshot::IncludesCode(kind)) {
+    ASSERT(instructions_buffer != NULL);
+  }
+  if (instructions_buffer != NULL) {
+    instructions_reader_ =
+        new (zone_) InstructionsReader(instructions_buffer, data_buffer);
+  }
+}
+
+
+Deserializer::~Deserializer() {
+  delete[] clusters_;
+}
+
+
+DeserializationCluster* Deserializer::ReadCluster() {
+  intptr_t cid = ReadCid();
+
+  Zone* Z = zone_;
+  if ((cid > kNumPredefinedCids) ||
+      (cid == kInstanceCid) ||
+      RawObject::IsTypedDataViewClassId(cid)) {
+    return new (Z) InstanceDeserializationCluster(cid);
+  }
+  if (RawObject::IsExternalTypedDataClassId(cid)) {
+    return new (Z) ExternalTypedDataDeserializationCluster(cid);
+  }
+  if (RawObject::IsTypedDataClassId(cid)) {
+    return new (Z) TypedDataDeserializationCluster(cid);
+  }
+
+  switch (cid) {
+    case kClassCid: return new (Z) ClassDeserializationCluster();
+    case kUnresolvedClassCid:
+      return new (Z) UnresolvedClassDeserializationCluster();
+    case kTypeArgumentsCid:
+      return new (Z) TypeArgumentsDeserializationCluster();
+    case kPatchClassCid: return new (Z) PatchClassDeserializationCluster();
+    case kFunctionCid: return new (Z) FunctionDeserializationCluster();
+    case kClosureDataCid: return new (Z) ClosureDataDeserializationCluster();
+    case kRedirectionDataCid:
+      return new (Z) RedirectionDataDeserializationCluster();
+    case kFieldCid: return new (Z) FieldDeserializationCluster();
+    case kLiteralTokenCid: return new (Z) LiteralTokenDeserializationCluster();
+    case kTokenStreamCid: return new (Z) TokenStreamDeserializationCluster();
+    case kScriptCid: return new (Z) ScriptDeserializationCluster();
+    case kLibraryCid: return new (Z) LibraryDeserializationCluster();
+    case kNamespaceCid: return new (Z) NamespaceDeserializationCluster();
+    case kCodeCid: return new (Z) CodeDeserializationCluster();
+    case kObjectPoolCid: return new (Z) ObjectPoolDeserializationCluster();
+    case kPcDescriptorsCid:
+    case kStackmapCid:
+      return new (Z) RODataDeserializationCluster();
+    case kExceptionHandlersCid:
+      return new (Z) ExceptionHandlersDeserializationCluster();
+    case kContextCid: return new (Z) ContextDeserializationCluster();
+    case kContextScopeCid: return new (Z) ContextScopeDeserializationCluster();
+    case kICDataCid: return new (Z) ICDataDeserializationCluster();
+    case kMegamorphicCacheCid:
+      return new (Z) MegamorphicCacheDeserializationCluster();
+    case kSubtypeTestCacheCid:
+      return new (Z) SubtypeTestCacheDeserializationCluster();
+    case kLanguageErrorCid:
+      return new (Z) LanguageErrorDeserializationCluster();
+    case kUnhandledExceptionCid:
+      return new (Z) UnhandledExceptionDeserializationCluster();
+    case kLibraryPrefixCid:
+      return new (Z) LibraryPrefixDeserializationCluster();
+    case kTypeCid: return new (Z) TypeDeserializationCluster();
+    case kTypeRefCid: return new (Z) TypeRefDeserializationCluster();
+    case kTypeParameterCid:
+      return new (Z) TypeParameterDeserializationCluster();
+    case kBoundedTypeCid: return new (Z) BoundedTypeDeserializationCluster();
+    case kClosureCid: return new (Z) ClosureDeserializationCluster();
+    case kMintCid: return new (Z) MintDeserializationCluster();
+    case kBigintCid: return new (Z) BigintDeserializationCluster();
+    case kDoubleCid: return new (Z) DoubleDeserializationCluster();
+    case kGrowableObjectArrayCid:
+      return new (Z) GrowableObjectArrayDeserializationCluster();
+    case kStacktraceCid: return new (Z) StacktraceDeserializationCluster();
+    case kRegExpCid: return new (Z) RegExpDeserializationCluster();
+    case kLinkedHashMapCid:
+      return new (Z) LinkedHashMapDeserializationCluster();
+    case kArrayCid:
+      return new (Z) ArrayDeserializationCluster(kArrayCid);
+    case kImmutableArrayCid:
+      return new (Z) ArrayDeserializationCluster(kImmutableArrayCid);
+    case kOneByteStringCid: {
+      if (Snapshot::IncludesCode(kind_)) {
+        return new (Z) RODataDeserializationCluster();
+      } else {
+        return new (Z) OneByteStringDeserializationCluster();
+      }
+    }
+    case kTwoByteStringCid: {
+      if (Snapshot::IncludesCode(kind_)) {
+        return new (Z) RODataDeserializationCluster();
+      } else {
+        return new (Z) TwoByteStringDeserializationCluster();
+      }
+    }
+    default: break;
+  }
+  FATAL1("No cluster defined for cid %" Pd, cid);
+  return NULL;
+}
+
+
+RawApiError* Deserializer::VerifyVersionAndFeatures() {
+  // If the version string doesn't match, return an error.
+  // Note: New things are allocated only if we're going to return an error.
+
+  const char* expected_version = Version::SnapshotString();
+  ASSERT(expected_version != NULL);
+  const intptr_t version_len = strlen(expected_version);
+  if (PendingBytes() < version_len) {
+    const intptr_t kMessageBufferSize = 128;
+    char message_buffer[kMessageBufferSize];
+    OS::SNPrint(message_buffer,
+                kMessageBufferSize,
+                "No full snapshot version found, expected '%s'",
+                expected_version);
+    // This can also fail while bringing up the VM isolate, so make sure to
+    // allocate the error message in old space.
+    const String& msg = String::Handle(String::New(message_buffer, Heap::kOld));
+    return ApiError::New(msg, Heap::kOld);
+  }
+
+  const char* version = reinterpret_cast<const char*>(CurrentBufferAddress());
+  ASSERT(version != NULL);
+  if (strncmp(version, expected_version, version_len)) {
+    const intptr_t kMessageBufferSize = 256;
+    char message_buffer[kMessageBufferSize];
+    char* actual_version = OS::StrNDup(version, version_len);
+    OS::SNPrint(message_buffer,
+                kMessageBufferSize,
+                "Wrong %s snapshot version, expected '%s' found '%s'",
+                (Snapshot::IsFull(kind_)) ? "full" : "script",
+                expected_version,
+                actual_version);
+    free(actual_version);
+    // This can also fail while bringing up the VM isolate, so make sure to
+    // allocate the error message in old space.
+    const String& msg = String::Handle(String::New(message_buffer, Heap::kOld));
+    return ApiError::New(msg, Heap::kOld);
+  }
+  Advance(version_len);
+
+  const char* expected_features = Dart::FeaturesString(kind_);
+  ASSERT(expected_features != NULL);
+  const intptr_t expected_len = strlen(expected_features);
+
+  const char* features = reinterpret_cast<const char*>(CurrentBufferAddress());
+  ASSERT(features != NULL);
+  intptr_t buffer_len = OS::StrNLen(features, PendingBytes());
+  if ((buffer_len != expected_len) ||
+      strncmp(features, expected_features, expected_len)) {
+    const intptr_t kMessageBufferSize = 256;
+    char message_buffer[kMessageBufferSize];
+    char* actual_features = OS::StrNDup(features, buffer_len < 128 ? buffer_len
+                                                                   : 128);
+    OS::SNPrint(message_buffer,
+                kMessageBufferSize,
+                "Wrong features in snapshot, expected '%s' found '%s'",
+                expected_features,
+                actual_features);
+    free(const_cast<char*>(expected_features));
+    free(actual_features);
+    // This can also fail while bringing up the VM isolate, so make sure to
+    // allocate the error message in old space.
+    const String& msg = String::Handle(String::New(message_buffer, Heap::kOld));
+    return ApiError::New(msg, Heap::kOld);
+  }
+  free(const_cast<char*>(expected_features));
+  Advance(expected_len + 1);
+  return ApiError::null();
+}
+
+
+void Deserializer::Prepare() {
+  num_objects_ = Read<int32_t>();
+  num_clusters_ = Read<int32_t>();
+
+  clusters_ = new DeserializationCluster*[num_clusters_];
+  refs_ = Array::New(num_objects_ + 1, Heap::kOld);
+}
+
+
+void Deserializer::Deserialize() {
+  // TODO(rmacnak): Verify num of base objects.
+
+  {
+    NOT_IN_PRODUCT(TimelineDurationScope tds(thread(),
+        Timeline::GetIsolateStream(), "ReadAlloc"));
+    for (intptr_t i = 0; i < num_clusters_; i++) {
+      clusters_[i] = ReadCluster();
+      clusters_[i]->ReadAlloc(this);
+#if defined(DEBUG)
+      intptr_t serializers_next_ref_index_ = Read<intptr_t>();
+      ASSERT(serializers_next_ref_index_ == next_ref_index_);
+#endif
+    }
+  }
+
+  // We should have completely filled the ref array.
+  ASSERT((next_ref_index_ - 1) == num_objects_);
+
+  {
+    NOT_IN_PRODUCT(TimelineDurationScope tds(thread(),
+        Timeline::GetIsolateStream(), "ReadFill"));
+    for (intptr_t i = 0; i < num_clusters_; i++) {
+      clusters_[i]->ReadFill(this);
+#if defined(DEBUG)
+      intptr_t section_marker = Read<intptr_t>();
+      ASSERT(section_marker == kSectionMarker);
+#endif
+    }
+  }
+}
+
+class HeapLocker : public StackResource {
+ public:
+  HeapLocker(Thread* thread, PageSpace* page_space)
+      : StackResource(thread), page_space_(page_space) {
+        page_space_->AcquireDataLock();
+  }
+  ~HeapLocker() {
+    page_space_->ReleaseDataLock();
+  }
+
+ private:
+  PageSpace* page_space_;
+};
+
+
+void Deserializer::AddVMIsolateBaseObjects() {
+  // These objects are always allocated by Object::InitOnce, so they are not
+  // written into the snapshot.
+
+  AddBaseObject(Object::null());
+  AddBaseObject(Object::sentinel().raw());
+  AddBaseObject(Object::transition_sentinel().raw());
+  AddBaseObject(Object::empty_array().raw());
+  AddBaseObject(Object::zero_array().raw());
+  AddBaseObject(Object::dynamic_type().raw());
+  AddBaseObject(Object::void_type().raw());
+  AddBaseObject(Bool::True().raw());
+  AddBaseObject(Bool::False().raw());
+  AddBaseObject(Object::extractor_parameter_types().raw());
+  AddBaseObject(Object::extractor_parameter_names().raw());
+  AddBaseObject(Object::empty_context_scope().raw());
+  AddBaseObject(Object::empty_descriptors().raw());
+  AddBaseObject(Object::empty_var_descriptors().raw());
+  AddBaseObject(Object::empty_exception_handlers().raw());
+
+  for (intptr_t i = 0; i < ArgumentsDescriptor::kCachedDescriptorCount; i++) {
+    AddBaseObject(ArgumentsDescriptor::cached_args_descriptors_[i]);
+  }
+  for (intptr_t i = 0; i < ICData::kCachedICDataArrayCount; i++) {
+    AddBaseObject(ICData::cached_icdata_arrays_[i]);
+  }
+
+  ClassTable* table = isolate()->class_table();
+  for (intptr_t cid = kClassCid; cid <= kUnwindErrorCid; cid++) {
+    // Error has no class object.
+    if (cid != kErrorCid) {
+      ASSERT(table->HasValidClassAt(cid));
+      AddBaseObject(table->At(cid));
+    }
+  }
+  AddBaseObject(table->At(kDynamicCid));
+  AddBaseObject(table->At(kVoidCid));
+}
+
+
+void Deserializer::ReadVMSnapshot() {
+  Array& symbol_table = Array::Handle(zone_);
+  Array& refs = Array::Handle(zone_);
+  Prepare();
+
+  {
+    NoSafepointScope no_safepoint;
+    HeapLocker hl(thread(), heap_->old_space());

[siva, 2016/06/30 00:06:07]

Why do you need to lock the heap pages, no other threads should be running while
we read the VM snapshot and isolate snapshot right?

[rmacnak, 2016/06/30 01:39:21]

Comes from the old full snapshot reading code. Removing this triggers asserts in
old_space->TryAllocateDataBumpLocked.

+
+    AddVMIsolateBaseObjects();
+
+    Deserialize();
+
+    // Read roots.
+    symbol_table ^= ReadRef();
+    isolate()->object_store()->set_symbol_table(symbol_table);
+    ReadRef();  // Script list.
+    if (Snapshot::IncludesCode(kind_)) {
+      StubCode::ReadRef(this);
+    }
+
+#if defined(DEBUG)
+    intptr_t section_marker = Read<intptr_t>();
+    ASSERT(section_marker == kSectionMarker);
+#endif
+
+    refs = refs_;
+    refs_ = NULL;
+  }
+
+  Symbols::InitOnceFromSnapshot(isolate());
+
+  Object::set_vm_isolate_snapshot_object_table(refs);
+
+#if defined(DEBUG)
+  isolate()->ValidateClassTable();
+#endif
+}
+
+void Deserializer::ReadFullSnapshot(ObjectStore* object_store) {
+  Array& refs = Array::Handle();
+  Prepare();
+
+  {
+    NoSafepointScope no_safepoint;
+    HeapLocker hl(thread(), heap_->old_space());
+
+    // N.B.: Skipping index 0 because ref 0 is illegal.
+    const Array& base_objects = Object::vm_isolate_snapshot_object_table();
+    for (intptr_t i = 1; i < base_objects.Length(); i++) {
+      AddBaseObject(base_objects.At(i));
+    }
+
+    Deserialize();
+
+    // Read roots.
+    RawObject** from = object_store->from();
+    RawObject** to = object_store->to_snapshot(kind_);
+    for (RawObject** p = from; p <= to; p++) {
+      *p = ReadRef();
+    }
+
+#if defined(DEBUG)
+    intptr_t section_marker = Read<intptr_t>();
+    ASSERT(section_marker == kSectionMarker);
+#endif
+
+    refs = refs_;
+    refs_ = NULL;
+  }
+
+#if defined(DEBUG)
+  Isolate* isolate = thread()->isolate();
+  isolate->ValidateClassTable();
+  isolate->heap()->Verify();
+#endif
+
+  {
+    NOT_IN_PRODUCT(TimelineDurationScope tds(thread(),
+        Timeline::GetIsolateStream(), "PostLoad"));
+    for (intptr_t i = 0; i < num_clusters_; i++) {
+      clusters_[i]->PostLoad(refs, kind_, zone_);
+    }
+  }
+
+  // Setup native resolver for bootstrap impl.
+  Bootstrap::SetupNativeResolver();
+}
+
+
+// An object visitor which will iterate over all the script objects in the heap
+// and either count them or collect them into an array. This is used during
+// full snapshot generation of the VM isolate to write out all script
+// objects and their accompanying token streams.
+class ScriptVisitor : public ObjectVisitor {
+ public:
+  explicit ScriptVisitor(Thread* thread) :
+      objHandle_(Object::Handle(thread->zone())),
+      count_(0),
+      scripts_(NULL) {}
+
+  ScriptVisitor(Thread* thread, const Array* scripts) :
+      objHandle_(Object::Handle(thread->zone())),
+      count_(0),
+      scripts_(scripts) {}
+
+  void VisitObject(RawObject* obj) {
+    if (obj->IsScript()) {
+      if (scripts_ != NULL) {
+        objHandle_ = obj;
+        scripts_->SetAt(count_, objHandle_);
+      }
+      count_ += 1;
+    }
+  }
+
+  intptr_t count() const { return count_; }
+
+ private:
+  Object& objHandle_;
+  intptr_t count_;
+  const Array* scripts_;
+};
+
+
+
+FullSnapshotWriter::FullSnapshotWriter(Snapshot::Kind kind,
+                                       uint8_t** vm_isolate_snapshot_buffer,
+                                       uint8_t** isolate_snapshot_buffer,
+                                       ReAlloc alloc,
+                                       InstructionsWriter* instructions_writer)
+    : thread_(Thread::Current()),
+      kind_(kind),
+      vm_isolate_snapshot_buffer_(vm_isolate_snapshot_buffer),
+      isolate_snapshot_buffer_(isolate_snapshot_buffer),
+      alloc_(alloc),
+      vm_isolate_snapshot_size_(0),
+      isolate_snapshot_size_(0),
+      instructions_writer_(instructions_writer),
+      scripts_(Array::Handle(zone())),
+      saved_symbol_table_(Array::Handle(zone())),
+      new_vm_symbol_table_(Array::Handle(zone())) {
+  ASSERT(isolate_snapshot_buffer_ != NULL);
+  ASSERT(alloc_ != NULL);
+  ASSERT(isolate() != NULL);
+  ASSERT(ClassFinalizer::AllClassesFinalized());
+  ASSERT(isolate() != NULL);
+  ASSERT(heap() != NULL);
+  ObjectStore* object_store = isolate()->object_store();
+  ASSERT(object_store != NULL);
+
+#if defined(DEBUG)
+  // Ensure the class table is valid.
+  isolate()->ValidateClassTable();
+#endif
+  // Can't have any mutation happening while we're serializing.
+  ASSERT(isolate()->background_compiler() == NULL);
+
+  if (vm_isolate_snapshot_buffer != NULL) {
+    NOT_IN_PRODUCT(TimelineDurationScope tds(thread(),
+        Timeline::GetIsolateStream(), "PrepareNewVMIsolate"));
+
+    // Collect all the script objects and their accompanying token stream
+    // objects into an array so that we can write it out as part of the VM
+    // isolate snapshot. We first count the number of script objects, allocate
+    // an array and then fill it up with the script objects.
+    ScriptVisitor scripts_counter(thread());
+    heap()->IterateOldObjects(&scripts_counter);
+    Dart::vm_isolate()->heap()->IterateOldObjects(&scripts_counter);
+    intptr_t count = scripts_counter.count();
+    scripts_ = Array::New(count, Heap::kOld);
+    ScriptVisitor script_visitor(thread(), &scripts_);
+    heap()->IterateOldObjects(&script_visitor);
+    Dart::vm_isolate()->heap()->IterateOldObjects(&script_visitor);
+    ASSERT(script_visitor.count() == count);
+
+    // Tuck away the current symbol table.
+    saved_symbol_table_ = object_store->symbol_table();
+
+    // Create a unified symbol table that will be written as the vm isolate's
+    // symbol table.
+    new_vm_symbol_table_ = Symbols::UnifiedSymbolTable();
+
+    // Create an empty symbol table that will be written as the isolate's symbol
+    // table.
+    Symbols::SetupSymbolTable(isolate());
+  } else {
+    // Reuse the current vm isolate.

[siva, 2016/06/30 00:06:08]

Why have this empty block here?

[rmacnak, 2016/06/30 01:39:21]

Scoping the comment.

+  }
+}
+
+FullSnapshotWriter::~FullSnapshotWriter() {
+  // We may run Dart code afterwards, restore the symbol table if needed.
+  if (!saved_symbol_table_.IsNull()) {
+    isolate()->object_store()->set_symbol_table(saved_symbol_table_);
+    saved_symbol_table_ = Array::null();
+  }
+  new_vm_symbol_table_ = Array::null();
+  scripts_ = Array::null();
+}
+
+
+intptr_t FullSnapshotWriter::WriteVmIsolateSnapshot() {
+  NOT_IN_PRODUCT(TimelineDurationScope tds(thread(),
+      Timeline::GetIsolateStream(), "WriteVmIsolateSnapshot"));
+
+  ASSERT(vm_isolate_snapshot_buffer_ != NULL);
+  Serializer serializer(thread(),
+                        kind_,
+                        vm_isolate_snapshot_buffer_,
+                        alloc_,
+                        kInitialSize,
+                        instructions_writer_);
+
+  serializer.ReserveHeader();
+  serializer.WriteVersionAndFeatures();
+  /*
+   * Now Write out the following
+   * - the symbol table
+   * - all the scripts and token streams for these scripts
+   * - the stub code (precompiled snapshots only)
+   **/
+  intptr_t num_objects = serializer.WriteVMSnapshot(new_vm_symbol_table_,
+                                                    scripts_);
+  serializer.FillHeader(serializer.kind());
+
+  vm_isolate_snapshot_size_ = serializer.bytes_written();
+  return num_objects;
+}
+
+
+void FullSnapshotWriter::WriteIsolateFullSnapshot(
+    intptr_t num_base_objects) {
+  NOT_IN_PRODUCT(TimelineDurationScope tds(thread(),
+      Timeline::GetIsolateStream(), "WriteIsolateFullSnapshot"));
+
+  Serializer serializer(thread(),
+                        kind_,
+                        isolate_snapshot_buffer_,
+                        alloc_,
+                        kInitialSize,
+                        instructions_writer_);
+  ObjectStore* object_store = isolate()->object_store();
+  ASSERT(object_store != NULL);
+
+  serializer.ReserveHeader();
+  serializer.WriteVersionAndFeatures();
+  serializer.WriteFullSnapshot(num_base_objects, object_store);
+  serializer.FillHeader(serializer.kind());
+
+  isolate_snapshot_size_ = serializer.bytes_written();
+}
+
+
+void FullSnapshotWriter::WriteFullSnapshot() {
+  intptr_t num_base_objects;
+  if (vm_isolate_snapshot_buffer() != NULL) {
+    num_base_objects = WriteVmIsolateSnapshot();
+    ASSERT(num_base_objects != 0);
+  } else {
+    num_base_objects = 0;
+  }
+
+  WriteIsolateFullSnapshot(num_base_objects);
+
+  if (Snapshot::IncludesCode(kind_)) {
+    instructions_writer_->Write();
+
+    OS::Print("VMIsolate(CodeSize): %" Pd "\n", VmIsolateSnapshotSize());
+    OS::Print("Isolate(CodeSize): %" Pd "\n", IsolateSnapshotSize());
+    OS::Print("Instructions(CodeSize): %" Pd "\n",
+              instructions_writer_->binary_size());
+    intptr_t total = VmIsolateSnapshotSize() +
+                     IsolateSnapshotSize() +
+                     instructions_writer_->binary_size();
+    OS::Print("Total(CodeSize): %" Pd "\n", total);
+  }
+}
+
+
+RawApiError* IsolateSnapshotReader::ReadFullSnapshot() {
+  Deserializer deserializer(thread_,
+                            kind_,
+                            buffer_,
+                            size_,
+                            instructions_buffer_,
+                            data_buffer_);
+
+  RawApiError* error = deserializer.VerifyVersionAndFeatures();
+  if (error != ApiError::null()) {
+    return error;
+  }
+
+  deserializer.ReadFullSnapshot(thread_->isolate()->object_store());
+
+  return ApiError::null();
+}
+
+
+RawApiError* VmIsolateSnapshotReader::ReadVmIsolateSnapshot() {
+  Deserializer deserializer(thread_,
+                            kind_,
+                            buffer_,
+                            size_,
+                            instructions_buffer_,
+                            data_buffer_);
+
+  RawApiError* error = deserializer.VerifyVersionAndFeatures();
+  if (error != ApiError::null()) {
+    return error;
+  }
+
+  deserializer.ReadVMSnapshot();
+
+  Dart::set_instructions_snapshot_buffer(instructions_buffer_);
+  Dart::set_data_snapshot_buffer(data_buffer_);
+
+  return ApiError::null();
+}
+
+}  // namespace dart