1 files changed, 30 insertions, 0 deletions
diff --git a/deps/v8/src/runtime/runtime-weak-refs.cc b/deps/v8/src/runtime/runtime-weak-refs.cc
new file mode 100644
index 00000000000..f73017c5842
--- /dev/null
+++ b/deps/v8/src/runtime/runtime-weak-refs.cc
@@ -0,0 +1,30 @@
+// Copyright 2020 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.
+
+#include "src/runtime/runtime-utils.h"
+
+#include "src/execution/arguments-inl.h"
+#include "src/objects/js-weak-refs-inl.h"
+
+namespace v8 {
+namespace internal {
+
+RUNTIME_FUNCTION(Runtime_ShrinkFinalizationRegistryUnregisterTokenMap) {
+  HandleScope scope(isolate);
+  DCHECK_EQ(1, args.length());
+  CONVERT_ARG_HANDLE_CHECKED(JSFinalizationRegistry, finalization_registry, 0);
+
+  if (!finalization_registry->key_map().IsUndefined(isolate)) {
+    Handle<SimpleNumberDictionary> key_map =
+        handle(SimpleNumberDictionary::cast(finalization_registry->key_map()),
+               isolate);
+    key_map = SimpleNumberDictionary::Shrink(isolate, key_map);
+    finalization_registry->set_key_map(*key_map);
+  }
+
+  return ReadOnlyRoots(isolate).undefined_value();
+}
+
+}  // namespace internal
+}  // namespace v8