chromium/v8/src/heap/mutable-page-metadata.h

// 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.

#ifndef V8_HEAP_MUTABLE_PAGE_METADATA_H_
#define V8_HEAP_MUTABLE_PAGE_METADATA_H_

#include <atomic>

#include "src/base/macros.h"
#include "src/base/platform/mutex.h"
#include "src/common/globals.h"
#include "src/heap/base/active-system-pages.h"
#include "src/heap/list.h"
#include "src/heap/marking.h"
#include "src/heap/memory-chunk-layout.h"
#include "src/heap/memory-chunk-metadata.h"
#include "src/heap/slot-set.h"

namespace v8 {
namespace internal {

class FreeListCategory;
class Space;

// MutablePageMetadata represents a memory region owned by a specific space.
// It is divided into the header and the body. Chunk start is always
// 1MB aligned. Start of the body is aligned so it can accommodate
// any heap object.
class MutablePageMetadata : public MemoryChunkMetadata { … };

}  // namespace internal

namespace base {
// Define special hash function for chunk pointers, to be used with std data
// structures, e.g. std::unordered_set<MutablePageMetadata*,
// base::hash<MutablePageMetadata*>
template <>
struct hash<i::MutablePageMetadata*> : hash<i::MemoryChunkMetadata*> { … };
template <>
struct hash<const i::MutablePageMetadata*>
    : hash<const i::MemoryChunkMetadata*> { … };
}  // namespace base

}  // namespace v8

#endif  // V8_HEAP_MUTABLE_PAGE_METADATA_H_