[serializer] split up src/snapshot/serialize.*

src/snapshot/partial-serializer.h

+// Copyright 2016 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.
+
+#ifndef V8_SNAPSHOT_PARTIAL_SERIALIZER_H_
+#define V8_SNAPSHOT_PARTIAL_SERIALIZER_H_
+
+#include "src/address-map.h"
+#include "src/snapshot/serializer.h"
+
+namespace v8 {
+namespace internal {
+
+class PartialSerializer : public Serializer {
+ public:
+  PartialSerializer(Isolate* isolate, Serializer* startup_snapshot_serializer,
+                    SnapshotByteSink* sink);
+
+  ~PartialSerializer() override;
+
+  // Serialize the objects reachable from a single object pointer.
+  void Serialize(Object** o);
+
+ private:
+  class PartialCacheIndexMap : public AddressMapBase {
+   public:
+    PartialCacheIndexMap() : map_(HashMap::PointersMatch) {}
+
+    static const int kInvalidIndex = -1;
+
+    // Lookup object in the map. Return its index if found, or create
+    // a new entry with new_index as value, and return kInvalidIndex.
+    int LookupOrInsert(HeapObject* obj, int new_index) {
+      HashMap::Entry* entry = LookupEntry(&map_, obj, false);
+      if (entry != NULL) return GetValue(entry);
+      SetValue(LookupEntry(&map_, obj, true), static_cast<uint32_t>(new_index));
+      return kInvalidIndex;
+    }
+
+   private:
+    HashMap map_;
+
+    DISALLOW_COPY_AND_ASSIGN(PartialCacheIndexMap);
+  };
+
+  void SerializeObject(HeapObject* o, HowToCode how_to_code,
+                       WhereToPoint where_to_point, int skip) override;
+
+  int PartialSnapshotCacheIndex(HeapObject* o);
+  bool ShouldBeInThePartialSnapshotCache(HeapObject* o);
+
+  Serializer* startup_serializer_;
+  Object* global_object_;
+  PartialCacheIndexMap partial_cache_index_map_;
+  DISALLOW_COPY_AND_ASSIGN(PartialSerializer);
+};
+
+}  // namespace internal
+}  // namespace v8
+
+#endif  // V8_SNAPSHOT_PARTIAL_SERIALIZER_H_