chromium/v8/src/objects/property-details.h

// Copyright 2012 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_OBJECTS_PROPERTY_DETAILS_H_
#define V8_OBJECTS_PROPERTY_DETAILS_H_

#include "include/v8-object.h"
#include "src/base/bit-field.h"
#include "src/common/globals.h"
#include "src/flags/flags.h"
#include "src/utils/allocation.h"

namespace v8 {
namespace internal {

// ES6 6.1.7.1
enum PropertyAttributes { … };

V8_INLINE PropertyAttributes PropertyAttributesFromInt(int value) { … }

// Number of distinct bits in PropertyAttributes.
static const int kPropertyAttributesBitsCount = …;

static const int kPropertyAttributesCombinationsCount = …;

enum PropertyFilter { … };
// Enable fast comparisons of PropertyAttributes against PropertyFilters.
static_assert …;
static_assert …;
static_assert …;
static_assert …;
static_assert …;
static_assert …;
static_assert …;
static_assert …;
static_assert …;
static_assert …;
static_assert …;

// Assert that kPropertyAttributesBitsCount value matches the definition of
// ALL_ATTRIBUTES_MASK.
static_assert …;

class Smi;
class TypeInfo;

// Order of kinds is significant.
// Must fit in the BitField PropertyDetails::KindField.
enum class PropertyKind { … };

// Order of modes is significant.
// Must fit in the BitField PropertyDetails::LocationField.
enum class PropertyLocation { … };

// Order of modes is significant.
// Must fit in the BitField PropertyDetails::ConstnessField.
enum class PropertyConstness { … };

class Representation { … };

static const int kDescriptorIndexBitCount = …;
static const int kFirstInobjectPropertyOffsetBitCount = …;
// The maximum number of descriptors we want in a descriptor array.  It should
// fit in a page and also the following should hold:
// kMaxNumberOfDescriptors + kFieldsAdded <= PropertyArray::kMaxLength.
static const int kMaxNumberOfDescriptors = …;
static const int kInvalidEnumCacheSentinel = …;

// A PropertyCell's property details contains a cell type that is meaningful if
// the cell is still valid (does not hold the hole).
enum class PropertyCellType { … };

// PropertyDetails captures type and attributes for a property.
// They are used both in property dictionaries and instance descriptors.
class PropertyDetails { … };

// kField location is more general than kDescriptor, kDescriptor generalizes
// only to itself.
inline bool IsGeneralizableTo(PropertyLocation a, PropertyLocation b) { … }

// PropertyConstness::kMutable constness is more general than
// VariableMode::kConst, VariableMode::kConst generalizes only to itself.
inline bool IsGeneralizableTo(PropertyConstness a, PropertyConstness b) { … }

inline PropertyConstness GeneralizeConstness(PropertyConstness a,
                                             PropertyConstness b) { … }

V8_EXPORT_PRIVATE std::ostream& operator<<(
    std::ostream& os, const Representation& representation);
V8_EXPORT_PRIVATE std::ostream& operator<<(
    std::ostream& os, const PropertyAttributes& attributes);
V8_EXPORT_PRIVATE std::ostream& operator<<(std::ostream& os,
                                           PropertyConstness constness);
V8_EXPORT_PRIVATE std::ostream& operator<<(std::ostream& os,
                                           PropertyCellType type);
}  // namespace internal
}  // namespace v8

#endif  // V8_OBJECTS_PROPERTY_DETAILS_H_