chromium/base/allocator/partition_allocator/src/partition_alloc/freeslot_bitmap_constants.h

// Copyright 2022 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef PARTITION_ALLOC_FREESLOT_BITMAP_CONSTANTS_H_
#define PARTITION_ALLOC_FREESLOT_BITMAP_CONSTANTS_H_

#include <cstdint>

#include "partition_alloc/buildflags.h"
#include "partition_alloc/partition_alloc_base/bits.h"
#include "partition_alloc/partition_alloc_base/compiler_specific.h"
#include "partition_alloc/partition_alloc_constants.h"
#include "partition_alloc/partition_alloc_forward.h"
#include "partition_alloc/reservation_offset_table.h"

namespace partition_alloc::internal {

FreeSlotBitmapCellType;
constexpr size_t kFreeSlotBitmapBitsPerCell = …;
constexpr size_t kFreeSlotBitmapOffsetMask = …;

// The number of bits necessary for the bitmap is equal to the maximum number of
// slots in a super page.
constexpr size_t kFreeSlotBitmapSize = …;

PA_ALWAYS_INLINE PAGE_ALLOCATOR_CONSTANTS_DECLARE_CONSTEXPR size_t
ReservedFreeSlotBitmapSize() { … }

PA_ALWAYS_INLINE PAGE_ALLOCATOR_CONSTANTS_DECLARE_CONSTEXPR size_t
CommittedFreeSlotBitmapSize() { … }

PA_ALWAYS_INLINE PAGE_ALLOCATOR_CONSTANTS_DECLARE_CONSTEXPR size_t
NumPartitionPagesPerFreeSlotBitmap() { … }

#if PA_BUILDFLAG(USE_FREESLOT_BITMAP)
PA_ALWAYS_INLINE uintptr_t SuperPageFreeSlotBitmapAddr(uintptr_t super_page) {
  PA_DCHECK(!(super_page % kSuperPageAlignment));
  return super_page + PartitionPageSize();
}
#endif

}  // namespace partition_alloc::internal

#endif  // PARTITION_ALLOC_FREESLOT_BITMAP_CONSTANTS_H_