Encode reservation meta data in the snapshot blob.

src/snapshot-external.cc

 // Copyright 2006-2008 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Used for building with external snapshots.
 
 #include "src/snapshot.h"
 
 #include "src/serialize.h"
 #include "src/snapshot-source-sink.h"
 #include "src/v8.h"  // for V8::Initialize
 
 namespace v8 {
 namespace internal {
 
 
 struct SnapshotImpl {
  public:
   const byte* data;
   int size;
-  int new_space_used;
-  int pointer_space_used;
-  int data_space_used;
-  int code_space_used;
-  int map_space_used;
-  int cell_space_used;
-  int property_cell_space_used;
-  int lo_space_used;
-
   const byte* context_data;
   int context_size;
-  int context_new_space_used;
-  int context_pointer_space_used;
-  int context_data_space_used;
-  int context_code_space_used;
-  int context_map_space_used;
-  int context_cell_space_used;
-  int context_property_cell_space_used;
-  int context_lo_space_used;
 };
 
 
 static SnapshotImpl* snapshot_impl_ = NULL;
 
 
 bool Snapshot::HaveASnapshotToStartFrom() {
   return snapshot_impl_ != NULL;
 }
 
 
 bool Snapshot::Initialize(Isolate* isolate) {
-  if (!HaveASnapshotToStartFrom())
-    return false;
+  if (!HaveASnapshotToStartFrom()) return false;
+  base::ElapsedTimer timer;
+  if (FLAG_profile_deserialization) timer.Start();
 
-  base::ElapsedTimer timer;
-  if (FLAG_profile_deserialization) {
-    timer.Start();
-  }
-  SnapshotByteSource source(snapshot_impl_->data, snapshot_impl_->size);
-  Deserializer deserializer(&source);
-  deserializer.AddReservation(NEW_SPACE, snapshot_impl_->new_space_used);
-  deserializer.AddReservation(OLD_POINTER_SPACE,
-                              snapshot_impl_->pointer_space_used);
-  deserializer.AddReservation(OLD_DATA_SPACE, snapshot_impl_->data_space_used);
-  deserializer.AddReservation(CODE_SPACE, snapshot_impl_->code_space_used);
-  deserializer.AddReservation(MAP_SPACE, snapshot_impl_->map_space_used);
-  deserializer.AddReservation(CELL_SPACE, snapshot_impl_->cell_space_used);
-  deserializer.AddReservation(PROPERTY_CELL_SPACE,
-                              snapshot_impl_->property_cell_space_used);
-  deserializer.AddReservation(LO_SPACE, snapshot_impl_->lo_space_used);
+
+  SnapshotData snapshot_data(snapshot_impl_->data, snapshot_impl_->size);
+  Deserializer deserializer(&snapshot_data);
   bool success = isolate->Init(&deserializer);
   if (FLAG_profile_deserialization) {
     double ms = timer.Elapsed().InMillisecondsF();
     PrintF("[Snapshot loading and deserialization took %0.3f ms]\n", ms);
   }
   return success;
 }
 
 
 Handle<Context> Snapshot::NewContextFromSnapshot(Isolate* isolate) {
-  if (!HaveASnapshotToStartFrom())
-    return Handle<Context>();
+  if (!HaveASnapshotToStartFrom()) return Handle<Context>();
 
-  SnapshotByteSource source(snapshot_impl_->context_data,
-                            snapshot_impl_->context_size);
-  Deserializer deserializer(&source);
-  deserializer.AddReservation(NEW_SPACE,
-                              snapshot_impl_->context_new_space_used);
-  deserializer.AddReservation(OLD_POINTER_SPACE,
-                              snapshot_impl_->context_pointer_space_used);
-  deserializer.AddReservation(OLD_DATA_SPACE,
-                              snapshot_impl_->context_data_space_used);
-  deserializer.AddReservation(CODE_SPACE,
-                              snapshot_impl_->context_code_space_used);
-  deserializer.AddReservation(MAP_SPACE,
-                              snapshot_impl_->context_map_space_used);
-  deserializer.AddReservation(CELL_SPACE,
-                              snapshot_impl_->context_cell_space_used);
-  deserializer.AddReservation(PROPERTY_CELL_SPACE,
-                              snapshot_impl_->context_property_cell_space_used);
-  deserializer.AddReservation(LO_SPACE, snapshot_impl_->context_lo_space_used);
+  SnapshotData snapshot_data(snapshot_impl_->context_data,
+                             snapshot_impl_->context_size);
+  Deserializer deserializer(&snapshot_data);
   Object* root;
   deserializer.DeserializePartial(isolate, &root);
   CHECK(root->IsContext());
   return Handle<Context>(Context::cast(root));
 }
 
 
 void SetSnapshotFromFile(StartupData* snapshot_blob) {
   DCHECK(snapshot_blob);
   DCHECK(snapshot_blob->data);
   DCHECK(snapshot_blob->raw_size > 0);
   DCHECK(!snapshot_impl_);
 
   snapshot_impl_ = new SnapshotImpl;
   SnapshotByteSource source(reinterpret_cast<const byte*>(snapshot_blob->data),
                             snapshot_blob->raw_size);
-
   bool success = source.GetBlob(&snapshot_impl_->data,
                                 &snapshot_impl_->size);
-  snapshot_impl_->new_space_used = source.GetInt();
-  snapshot_impl_->pointer_space_used = source.GetInt();
-  snapshot_impl_->data_space_used = source.GetInt();
-  snapshot_impl_->code_space_used = source.GetInt();
-  snapshot_impl_->map_space_used = source.GetInt();
-  snapshot_impl_->cell_space_used = source.GetInt();
-  snapshot_impl_->property_cell_space_used = source.GetInt();
-  snapshot_impl_->lo_space_used = source.GetInt();
-
   success &= source.GetBlob(&snapshot_impl_->context_data,
                             &snapshot_impl_->context_size);
-  snapshot_impl_->context_new_space_used = source.GetInt();
-  snapshot_impl_->context_pointer_space_used = source.GetInt();
-  snapshot_impl_->context_data_space_used = source.GetInt();
-  snapshot_impl_->context_code_space_used = source.GetInt();
-  snapshot_impl_->context_map_space_used = source.GetInt();
-  snapshot_impl_->context_cell_space_used = source.GetInt();
-  snapshot_impl_->context_property_cell_space_used = source.GetInt();
-  snapshot_impl_->context_lo_space_used = source.GetInt();
-
   DCHECK(success);
 }
 
 } }  // namespace v8::internal