Split GuardField into GuardFieldType and GuardFieldLength instructions.

runtime/vm/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/snapshot.h"
 
 #include "platform/assert.h"
 #include "vm/bigint_operations.h"
 #include "vm/bootstrap.h"
 #include "vm/class_finalizer.h"
@@ skipping 840 matching lines @@
       if ((offset != type_argument_field_offset) &&
           (kind_ == Snapshot::kMessage)) {
         // TODO(fschneider): Consider hoisting these lookups out of the loop.
         // This would involve creating a handle, since cls_ can't be reused
         // across the call to ReadObjectRef.
         cls_ = isolate()->class_table()->At(result_cid);
         array_ = cls_.OffsetToFieldMap();
         field_ ^= array_.At(offset >> kWordSizeLog2);
         ASSERT(!field_.IsNull());
         ASSERT(field_.Offset() == offset);
-        field_.UpdateGuardedCidAndLength(obj_);
+        field_.RecordStore(obj_);
       }
       // TODO(fschneider): Verify the guarded cid and length for other kinds of
       // snapshot (kFull, kScript) with asserts.
       offset += kWordSize;
     }
     if (kind_ == Snapshot::kFull) {
       // We create an uninitialized object in the case of full snapshots, so
       // we need to initialize any remaining padding area with the Null object.
       while (offset < instance_size) {
         result->SetFieldAtOffset(offset, Object::null_object());
@@ skipping 701 matching lines @@
     NoGCScope no_gc;
     WriteObject(obj.raw());
     UnmarkAll();
   } else {
     ThrowException(exception_type(), exception_msg());
   }
 }
 
 
 }  // namespace dart