Add a version of heap snapshots that use only fields and stack frames as roots and only include ins…

runtime/vm/object_graph.h

 // Copyright (c) 2014, 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.
 
 #ifndef RUNTIME_VM_OBJECT_GRAPH_H_
 #define RUNTIME_VM_OBJECT_GRAPH_H_
 
 #include "vm/allocation.h"
-#include "vm/object.h"
 
 namespace dart {
 
+class Array;
 class Isolate;
+class Object;
+class RawObject;
+class WriteStream;
 
 // Utility to traverse the object graph in an ordered fashion.
 // Example uses:
 // - find a retaining path from the isolate roots to a particular object, or
 // - determine how much memory is retained by some particular object(s).
 class ObjectGraph : public StackResource {
  public:
   class Stack;
 
   // Allows climbing the search tree all the way to the root.
@@ skipping 62 matching lines @@
   intptr_t RetainingPath(Object* obj, const Array& path);
 
   // Find the objects that reference 'obj'. Populates the provided array with
   // pairs of (object pointing to 'obj', offset of pointer in words), as far as
   // there is room. Returns the number of objects found.
   //
   // An object for which this function answers no inbound references might still
   // be live due to references from the stack or embedder handles.
   intptr_t InboundReferences(Object* obj, const Array& references);
 
+  enum SnapshotRoots { kVM, kUser };
+
   // Write the isolate's object graph to 'stream'. Smis and nulls are omitted.
   // Returns the number of nodes in the stream, including the root.
   // If collect_garabage is false, the graph will include weakly-reachable
   // objects.
   // TODO(koda): Document format; support streaming/chunking.
-  intptr_t Serialize(WriteStream* stream, bool collect_garbage);
+  intptr_t Serialize(WriteStream* stream,
+                     SnapshotRoots roots,
+                     bool collect_garbage);
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(ObjectGraph);
 };
 
 }  // namespace dart
 
 #endif  // RUNTIME_VM_OBJECT_GRAPH_H_