From 36d22d82aa202bb199967e9512281e9a53db42c9 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 21:33:14 +0200 Subject: Adding upstream version 115.7.0esr. Signed-off-by: Daniel Baumann --- js/src/gc/RelocationOverlay.h | 66 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 66 insertions(+) create mode 100644 js/src/gc/RelocationOverlay.h (limited to 'js/src/gc/RelocationOverlay.h') diff --git a/js/src/gc/RelocationOverlay.h b/js/src/gc/RelocationOverlay.h new file mode 100644 index 0000000000..047e763d44 --- /dev/null +++ b/js/src/gc/RelocationOverlay.h @@ -0,0 +1,66 @@ +/* -*- 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/. */ + +/* + * GC-internal definition of relocation overlay used while moving cells. + */ + +#ifndef gc_RelocationOverlay_h +#define gc_RelocationOverlay_h + +#include "mozilla/Assertions.h" + +#include + +#include "gc/Cell.h" + +namespace js { +namespace gc { + +/* + * This structure overlays a Cell that has been moved and provides a way to find + * its new location. It's used during generational and compacting GC. + */ +class RelocationOverlay : public Cell { + public: + /* The location the cell has been moved to, stored in the cell header. */ + Cell* forwardingAddress() const { + MOZ_ASSERT(isForwarded()); + return reinterpret_cast(header_.getForwardingAddress()); + } + + protected: + /* A list entry to track all relocated things. */ + RelocationOverlay* next_; + + explicit RelocationOverlay(Cell* dst); + + public: + static const RelocationOverlay* fromCell(const Cell* cell) { + return static_cast(cell); + } + + static RelocationOverlay* fromCell(Cell* cell) { + return static_cast(cell); + } + + static RelocationOverlay* forwardCell(Cell* src, Cell* dst); + + void setNext(RelocationOverlay* next) { + MOZ_ASSERT(isForwarded()); + next_ = next; + } + + RelocationOverlay* next() const { + MOZ_ASSERT(isForwarded()); + return next_; + } +}; + +} // namespace gc +} // namespace js + +#endif /* gc_RelocationOverlay_h */ -- cgit v1.2.3