1 files changed, 46 insertions, 0 deletions
diff --git a/js/src/gc/StableCellHasher.h b/js/src/gc/StableCellHasher.h
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+++ b/js/src/gc/StableCellHasher.h
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+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: set ts=8 sts=2 et sw=2 tw=80:
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef gc_StableCellHasher_h
+#define gc_StableCellHasher_h
+
+#include "js/RootingAPI.h"
+#include "js/TypeDecls.h"
+
+namespace js {
+
+// StableCellHasher itself is defined in js/public/RootingAPI.h.
+
+namespace gc {
+
+struct Cell;
+
+// Gets an existing UID in |uidp| if one exists.
+[[nodiscard]] bool MaybeGetUniqueId(Cell* cell, uint64_t* uidp);
+
+// Puts an existing UID in |uidp|, or creates a new UID for this Cell and
+// puts that into |uidp|. Returns false on OOM.
+[[nodiscard]] bool GetOrCreateUniqueId(Cell* cell, uint64_t* uidp);
+
+uint64_t GetUniqueIdInfallible(Cell* cell);
+
+// Return true if this cell has a UID associated with it.
+[[nodiscard]] bool HasUniqueId(Cell* cell);
+
+// Transfer an id from another cell. This must only be called on behalf of a
+// moving GC. This method is infallible.
+void TransferUniqueId(Cell* tgt, Cell* src);
+
+// Remove any unique id associated with this Cell.
+void RemoveUniqueId(Cell* cell);
+
+// Used to restore unique ID after JSObject::swap.
+bool SetOrUpdateUniqueId(JSContext* cx, Cell* cell, uint64_t uid);
+
+}  // namespace gc
+}  // namespace js
+
+#endif  // gc_StableCellHasher_h