chromium/v8/src/common/segmented-table.h

// Copyright 2024 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.

#ifndef V8_COMMON_SEGMENTED_TABLE_H_
#define V8_COMMON_SEGMENTED_TABLE_H_

#include "include/v8-internal.h"
#include "src/base/macros.h"
#include "src/common/code-memory-access.h"

namespace v8 {
namespace internal {

/**
 * A thread-safe table with a fixed maximum size split into segments.
 *
 * The table provides thread-safe methods to allocate and free of segments and
 * an inline freelist implementation. Allocation and Freeing of entries is
 * implemented in subclasses since it depends on if the table is manually
 * managed or GCed.
 *
 * For the purpose of memory management, the table is partitioned into Segments
 * (for example 64kb memory chunks) that are grouped together in "Spaces". All
 * segments in a space share a freelist, and so entry allocation and garbage
 * collection happen on the level of spaces.
 *
 * The Entry type defines how the freelist is represented. For that, it must
 * implement the following methods:
 * - void MakeFreelistEntry(uint32_t next_entry_index)
 * - uint32_t GetNextFreelistEntry()
 */
template <typename Entry, size_t size>
class V8_EXPORT_PRIVATE SegmentedTable { … };

}  // namespace internal
}  // namespace v8

#endif  // V8_COMMON_SEGMENTED_TABLE_H_