StableCellHasher.h (1415B)
1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- 2 * vim: set ts=8 sts=2 et sw=2 tw=80: 3 * This Source Code Form is subject to the terms of the Mozilla Public 4 * License, v. 2.0. If a copy of the MPL was not distributed with this 5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ 6 7 #ifndef gc_StableCellHasher_h 8 #define gc_StableCellHasher_h 9 10 #include "js/RootingAPI.h" 11 #include "js/TypeDecls.h" 12 13 // StableCellHasher itself is defined in js/public/RootingAPI.h. 14 15 namespace js::gc { 16 17 struct Cell; 18 19 // Gets an existing UID in |uidp| if one exists. 20 [[nodiscard]] bool MaybeGetUniqueId(Cell* cell, uint64_t* uidp); 21 22 // Puts an existing UID in |uidp|, or creates a new UID for this Cell and 23 // puts that into |uidp|. Returns false on OOM. 24 [[nodiscard]] bool GetOrCreateUniqueId(Cell* cell, uint64_t* uidp); 25 26 uint64_t GetUniqueIdInfallible(Cell* cell); 27 28 // Return true if this cell has a UID associated with it. 29 [[nodiscard]] bool HasUniqueId(Cell* cell); 30 31 // Transfer an id from another cell. This must only be called on behalf of a 32 // moving GC. This method is infallible. 33 void TransferUniqueId(Cell* tgt, Cell* src); 34 35 // Remove any unique id associated with this Cell. 36 void RemoveUniqueId(Cell* cell); 37 38 // Used to restore unique ID after JSObject::swap. 39 bool SetOrUpdateUniqueId(JSContext* cx, Cell* cell, uint64_t uid); 40 41 } // namespace js::gc 42 43 #endif // gc_StableCellHasher_h