Initial support for length guards on final fields.

runtime/vm/raw_object_snapshot.cc

 // Copyright (c) 2012, 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/bigint_operations.h"
 #include "vm/object.h"
 #include "vm/object_store.h"
 #include "vm/snapshot.h"
 #include "vm/symbols.h"
 #include "vm/visitor.h"
@@ skipping 803 matching lines @@
   Field& field = Field::ZoneHandle(reader->isolate(), NEW_OBJECT(Field));
   reader->AddBackRef(object_id, &field, kIsDeserialized);
 
   // Set the object tags.
   field.set_tags(tags);
 
   // Set all non object fields.
   field.set_token_pos(reader->ReadIntptrValue());
   field.set_guarded_cid(reader->ReadIntptrValue());
   field.set_is_nullable(reader->ReadIntptrValue());
+  field.set_guarded_list_length(reader->ReadIntptrValue());
   field.set_kind_bits(reader->Read<uint8_t>());
 
   // Set all the object fields.
   // TODO(5411462): Need to assert No GC can happen here, even though
   // allocations may happen.
   intptr_t num_flds = (field.raw()->to() - field.raw()->from());
   for (intptr_t i = 0; i <= num_flds; i++) {
     *(field.raw()->from() + i) = reader->ReadObjectRef();
   }
 
@@ skipping 13 matching lines @@
   writer->WriteInlinedObjectHeader(object_id);
 
   // Write out the class and tags information.
   writer->WriteVMIsolateObject(kFieldCid);
   writer->WriteIntptrValue(writer->GetObjectTags(this));
 
   // Write out all the non object fields.
   writer->WriteIntptrValue(ptr()->token_pos_);
   writer->WriteIntptrValue(ptr()->guarded_cid_);
   writer->WriteIntptrValue(ptr()->is_nullable_);
+  writer->WriteIntptrValue(ptr()->guarded_list_length_);
   writer->Write<uint8_t>(ptr()->kind_bits_);
 
   // Write out all the object pointer fields.
   SnapshotWriterVisitor visitor(writer);
   visitor.VisitPointers(from(), to());
 }
 
 
 RawLiteralToken* LiteralToken::ReadFrom(SnapshotReader* reader,
                                         intptr_t object_id,
@@ skipping 1775 matching lines @@
 }
 
 
 void RawMirrorReference::WriteTo(SnapshotWriter* writer,
                                  intptr_t object_id,
                                  Snapshot::Kind kind) {
   UNREACHABLE();
 }
 
 }  // namespace dart