chromium/v8/src/heap/memory-chunk-metadata.h

// Copyright 2019 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_MEMORY_CHUNK_METADATA_H_
#define V8_HEAP_MEMORY_CHUNK_METADATA_H_

#include <bit>
#include <type_traits>
#include <unordered_map>

#include "src/base/atomic-utils.h"
#include "src/base/flags.h"
#include "src/base/functional.h"
#include "src/common/globals.h"
#include "src/flags/flags.h"
#include "src/heap/marking.h"
#include "src/heap/memory-chunk-layout.h"
#include "src/heap/memory-chunk.h"
#include "src/objects/heap-object.h"
#include "src/utils/allocation.h"

namespace v8 {
namespace internal {

class BaseSpace;

class MemoryChunkMetadata { … };

}  // namespace internal

namespace base {

// Define special hash function for chunk pointers, to be used with std data
// structures, e.g.
// std::unordered_set<MemoryChunkMetadata*, base::hash<MemoryChunkMetadata*>
// This hash function discards the trailing zero bits (chunk alignment).
// Notice that, when pointer compression is enabled, it also discards the
// cage base.
template <>
struct hash<const i::MemoryChunkMetadata*> { … };

template <>
struct hash<i::MemoryChunkMetadata*> { … };

}  // namespace base
}  // namespace v8

#endif  // V8_HEAP_MEMORY_CHUNK_METADATA_H_