deps: update V8 to 7.6.303.28

PR-URL: https://github.com/nodejs/node/pull/28016
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Refael Ackermann (רפאל פלחי) <refack@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Michael Dawson <michael_dawson@ca.ibm.com>
Reviewed-By: Jiawen Geng <technicalcute@gmail.com>

1 files changed, 409 insertions, 0 deletions

diff --git a/deps/v8/src/objects/property-details.h b/deps/v8/src/objects/property-details.h
new file mode 100644
index 0000000000..7836575edf
--- /dev/null
+++ b/deps/v8/src/objects/property-details.h
@@ -0,0 +1,409 @@
+// 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.h"
+#include "src/utils/allocation.h"
+// TODO(bmeurer): Remove once FLAG_modify_field_representation_inplace is gone.
+#include "src/flags/flags.h"
+#include "src/utils/utils.h"
+
+namespace v8 {
+namespace internal {
+
+// ES6 6.1.7.1
+enum PropertyAttributes {
+  NONE = ::v8::None,
+  READ_ONLY = ::v8::ReadOnly,
+  DONT_ENUM = ::v8::DontEnum,
+  DONT_DELETE = ::v8::DontDelete,
+
+  ALL_ATTRIBUTES_MASK = READ_ONLY | DONT_ENUM | DONT_DELETE,
+
+  SEALED = DONT_DELETE,
+  FROZEN = SEALED | READ_ONLY,
+
+  ABSENT = 64,  // Used in runtime to indicate a property is absent.
+  // ABSENT can never be stored in or returned from a descriptor's attributes
+  // bitfield.  It is only used as a return value meaning the attributes of
+  // a non-existent property.
+};
+
+enum PropertyFilter {
+  ALL_PROPERTIES = 0,
+  ONLY_WRITABLE = 1,
+  ONLY_ENUMERABLE = 2,
+  ONLY_CONFIGURABLE = 4,
+  SKIP_STRINGS = 8,
+  SKIP_SYMBOLS = 16,
+  ONLY_ALL_CAN_READ = 32,
+  PRIVATE_NAMES_ONLY = 64,
+  ENUMERABLE_STRINGS = ONLY_ENUMERABLE | SKIP_SYMBOLS,
+};
+// Enable fast comparisons of PropertyAttributes against PropertyFilters.
+STATIC_ASSERT(ALL_PROPERTIES == static_cast<PropertyFilter>(NONE));
+STATIC_ASSERT(ONLY_WRITABLE == static_cast<PropertyFilter>(READ_ONLY));
+STATIC_ASSERT(ONLY_ENUMERABLE == static_cast<PropertyFilter>(DONT_ENUM));
+STATIC_ASSERT(ONLY_CONFIGURABLE == static_cast<PropertyFilter>(DONT_DELETE));
+STATIC_ASSERT(((SKIP_STRINGS | SKIP_SYMBOLS | ONLY_ALL_CAN_READ) &
+               ALL_ATTRIBUTES_MASK) == 0);
+STATIC_ASSERT(ALL_PROPERTIES ==
+              static_cast<PropertyFilter>(v8::PropertyFilter::ALL_PROPERTIES));
+STATIC_ASSERT(ONLY_WRITABLE ==
+              static_cast<PropertyFilter>(v8::PropertyFilter::ONLY_WRITABLE));
+STATIC_ASSERT(ONLY_ENUMERABLE ==
+              static_cast<PropertyFilter>(v8::PropertyFilter::ONLY_ENUMERABLE));
+STATIC_ASSERT(ONLY_CONFIGURABLE == static_cast<PropertyFilter>(
+                                       v8::PropertyFilter::ONLY_CONFIGURABLE));
+STATIC_ASSERT(SKIP_STRINGS ==
+              static_cast<PropertyFilter>(v8::PropertyFilter::SKIP_STRINGS));
+STATIC_ASSERT(SKIP_SYMBOLS ==
+              static_cast<PropertyFilter>(v8::PropertyFilter::SKIP_SYMBOLS));
+
+class Smi;
+class TypeInfo;
+
+// Order of kinds is significant.
+// Must fit in the BitField PropertyDetails::KindField.
+enum PropertyKind { kData = 0, kAccessor = 1 };
+
+// Order of modes is significant.
+// Must fit in the BitField PropertyDetails::LocationField.
+enum PropertyLocation { kField = 0, kDescriptor = 1 };
+
+// Order of modes is significant.
+// Must fit in the BitField PropertyDetails::ConstnessField.
+enum class PropertyConstness { kMutable = 0, kConst = 1 };
+
+class Representation {
+ public:
+  enum Kind { kNone, kSmi, kDouble, kHeapObject, kTagged, kNumRepresentations };
+
+  Representation() : kind_(kNone) {}
+
+  static Representation None() { return Representation(kNone); }
+  static Representation Tagged() { return Representation(kTagged); }
+  static Representation Smi() { return Representation(kSmi); }
+  static Representation Double() { return Representation(kDouble); }
+  static Representation HeapObject() { return Representation(kHeapObject); }
+
+  static Representation FromKind(Kind kind) { return Representation(kind); }
+
+  bool Equals(const Representation& other) const {
+    return kind_ == other.kind_;
+  }
+
+  bool IsCompatibleForLoad(const Representation& other) const {
+    return IsDouble() == other.IsDouble();
+  }
+
+  bool IsCompatibleForStore(const Representation& other) const {
+    return Equals(other);
+  }
+
+  bool CanBeInPlaceChangedTo(const Representation& other) const {
+    // If it's just a representation generalization case (i.e. property kind and
+    // attributes stays unchanged) it's fine to transition from None to anything
+    // but double without any modification to the object, because the default
+    // uninitialized value for representation None can be overwritten by both
+    // smi and tagged values. Doubles, however, would require a box allocation.
+    if (IsNone()) return !other.IsDouble();
+    if (!FLAG_modify_field_representation_inplace) return false;
+    return (IsSmi() || IsHeapObject()) && other.IsTagged();
+  }
+
+  bool is_more_general_than(const Representation& other) const {
+    if (IsHeapObject()) return other.IsNone();
+    return kind_ > other.kind_;
+  }
+
+  bool fits_into(const Representation& other) const {
+    return other.is_more_general_than(*this) || other.Equals(*this);
+  }
+
+  Representation generalize(Representation other) {
+    if (other.fits_into(*this)) return *this;
+    if (other.is_more_general_than(*this)) return other;
+    return Representation::Tagged();
+  }
+
+  int size() const {
+    DCHECK(!IsNone());
+    if (IsDouble()) return kDoubleSize;
+    DCHECK(IsTagged() || IsSmi() || IsHeapObject());
+    return kTaggedSize;
+  }
+
+  Kind kind() const { return static_cast<Kind>(kind_); }
+  bool IsNone() const { return kind_ == kNone; }
+  bool IsTagged() const { return kind_ == kTagged; }
+  bool IsSmi() const { return kind_ == kSmi; }
+  bool IsSmiOrTagged() const { return IsSmi() || IsTagged(); }
+  bool IsDouble() const { return kind_ == kDouble; }
+  bool IsHeapObject() const { return kind_ == kHeapObject; }
+
+  const char* Mnemonic() const {
+    switch (kind_) {
+      case kNone:
+        return "v";
+      case kTagged:
+        return "t";
+      case kSmi:
+        return "s";
+      case kDouble:
+        return "d";
+      case kHeapObject:
+        return "h";
+    }
+    UNREACHABLE();
+  }
+
+ private:
+  explicit Representation(Kind k) : kind_(k) {}
+
+  // Make sure kind fits in int8.
+  STATIC_ASSERT(kNumRepresentations <= (1 << kBitsPerByte));
+
+  int8_t kind_;
+};
+
+static const int kDescriptorIndexBitCount = 10;
+static const int kFirstInobjectPropertyOffsetBitCount = 7;
+// 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 = (1 << kDescriptorIndexBitCount) - 4;
+static const int kInvalidEnumCacheSentinel =
+    (1 << kDescriptorIndexBitCount) - 1;
+
+enum class PropertyCellType {
+  // Meaningful when a property cell does not contain the hole.
+  kUndefined,     // The PREMONOMORPHIC of property cells.
+  kConstant,      // Cell has been assigned only once.
+  kConstantType,  // Cell has been assigned only one type.
+  kMutable,       // Cell will no longer be tracked as constant.
+
+  // Meaningful when a property cell contains the hole.
+  kUninitialized = kUndefined,  // Cell has never been initialized.
+  kInvalidated = kConstant,     // Cell has been deleted, invalidated or never
+                                // existed.
+
+  // For dictionaries not holding cells.
+  kNoCell = kMutable,
+};
+
+enum class PropertyCellConstantType {
+  kSmi,
+  kStableMap,
+};
+
+// PropertyDetails captures type and attributes for a property.
+// They are used both in property dictionaries and instance descriptors.
+class PropertyDetails {
+ public:
+  // Property details for dictionary mode properties/elements.
+  PropertyDetails(PropertyKind kind, PropertyAttributes attributes,
+                  PropertyCellType cell_type, int dictionary_index = 0) {
+    value_ = KindField::encode(kind) | LocationField::encode(kField) |
+             AttributesField::encode(attributes) |
+             DictionaryStorageField::encode(dictionary_index) |
+             PropertyCellTypeField::encode(cell_type);
+  }
+
+  // Property details for fast mode properties.
+  PropertyDetails(PropertyKind kind, PropertyAttributes attributes,
+                  PropertyLocation location, PropertyConstness constness,
+                  Representation representation, int field_index = 0) {
+    value_ = KindField::encode(kind) | AttributesField::encode(attributes) |
+             LocationField::encode(location) |
+             ConstnessField::encode(constness) |
+             RepresentationField::encode(EncodeRepresentation(representation)) |
+             FieldIndexField::encode(field_index);
+  }
+
+  static PropertyDetails Empty(
+      PropertyCellType cell_type = PropertyCellType::kNoCell) {
+    return PropertyDetails(kData, NONE, cell_type);
+  }
+
+  int pointer() const { return DescriptorPointer::decode(value_); }
+
+  PropertyDetails set_pointer(int i) const {
+    return PropertyDetails(value_, i);
+  }
+
+  PropertyDetails set_cell_type(PropertyCellType type) const {
+    PropertyDetails details = *this;
+    details.value_ = PropertyCellTypeField::update(details.value_, type);
+    return details;
+  }
+
+  PropertyDetails set_index(int index) const {
+    PropertyDetails details = *this;
+    details.value_ = DictionaryStorageField::update(details.value_, index);
+    return details;
+  }
+
+  PropertyDetails CopyWithRepresentation(Representation representation) const {
+    return PropertyDetails(value_, representation);
+  }
+  PropertyDetails CopyWithConstness(PropertyConstness constness) const {
+    return PropertyDetails(value_, constness);
+  }
+  PropertyDetails CopyAddAttributes(PropertyAttributes new_attributes) const {
+    new_attributes =
+        static_cast<PropertyAttributes>(attributes() | new_attributes);
+    return PropertyDetails(value_, new_attributes);
+  }
+
+  // Conversion for storing details as Object.
+  explicit inline PropertyDetails(Smi smi);
+  inline Smi AsSmi() const;
+
+  static uint8_t EncodeRepresentation(Representation representation) {
+    return representation.kind();
+  }
+
+  static Representation DecodeRepresentation(uint32_t bits) {
+    return Representation::FromKind(static_cast<Representation::Kind>(bits));
+  }
+
+  PropertyKind kind() const { return KindField::decode(value_); }
+  PropertyLocation location() const { return LocationField::decode(value_); }
+  PropertyConstness constness() const { return ConstnessField::decode(value_); }
+
+  PropertyAttributes attributes() const {
+    return AttributesField::decode(value_);
+  }
+
+  bool HasKindAndAttributes(PropertyKind kind, PropertyAttributes attributes) {
+    return (value_ & (KindField::kMask | AttributesField::kMask)) ==
+           (KindField::encode(kind) | AttributesField::encode(attributes));
+  }
+
+  int dictionary_index() const {
+    return DictionaryStorageField::decode(value_);
+  }
+
+  Representation representation() const {
+    return DecodeRepresentation(RepresentationField::decode(value_));
+  }
+
+  int field_index() const { return FieldIndexField::decode(value_); }
+
+  inline int field_width_in_words() const;
+
+  static bool IsValidIndex(int index) {
+    return DictionaryStorageField::is_valid(index);
+  }
+
+  bool IsReadOnly() const { return (attributes() & READ_ONLY) != 0; }
+  bool IsConfigurable() const { return (attributes() & DONT_DELETE) == 0; }
+  bool IsDontEnum() const { return (attributes() & DONT_ENUM) != 0; }
+  bool IsEnumerable() const { return !IsDontEnum(); }
+  PropertyCellType cell_type() const {
+    return PropertyCellTypeField::decode(value_);
+  }
+
+  // Bit fields in value_ (type, shift, size). Must be public so the
+  // constants can be embedded in generated code.
+  class KindField : public BitField<PropertyKind, 0, 1> {};
+  class LocationField : public BitField<PropertyLocation, KindField::kNext, 1> {
+  };
+  class ConstnessField
+      : public BitField<PropertyConstness, LocationField::kNext, 1> {};
+  class AttributesField
+      : public BitField<PropertyAttributes, ConstnessField::kNext, 3> {};
+  static const int kAttributesReadOnlyMask =
+      (READ_ONLY << AttributesField::kShift);
+  static const int kAttributesDontDeleteMask =
+      (DONT_DELETE << AttributesField::kShift);
+  static const int kAttributesDontEnumMask =
+      (DONT_ENUM << AttributesField::kShift);
+
+  // Bit fields for normalized objects.
+  class PropertyCellTypeField
+      : public BitField<PropertyCellType, AttributesField::kNext, 2> {};
+  class DictionaryStorageField
+      : public BitField<uint32_t, PropertyCellTypeField::kNext, 23> {};
+
+  // Bit fields for fast objects.
+  class RepresentationField
+      : public BitField<uint32_t, AttributesField::kNext, 3> {};
+  class DescriptorPointer
+      : public BitField<uint32_t, RepresentationField::kNext,
+                        kDescriptorIndexBitCount> {};  // NOLINT
+  class FieldIndexField : public BitField<uint32_t, DescriptorPointer::kNext,
+                                          kDescriptorIndexBitCount> {
+  };  // NOLINT
+
+  // All bits for both fast and slow objects must fit in a smi.
+  STATIC_ASSERT(DictionaryStorageField::kNext <= 31);
+  STATIC_ASSERT(FieldIndexField::kNext <= 31);
+
+  static const int kInitialIndex = 1;
+
+#ifdef OBJECT_PRINT
+  // For our gdb macros, we should perhaps change these in the future.
+  void Print(bool dictionary_mode);
+#endif
+
+  enum PrintMode {
+    kPrintAttributes = 1 << 0,
+    kPrintFieldIndex = 1 << 1,
+    kPrintRepresentation = 1 << 2,
+    kPrintPointer = 1 << 3,
+
+    kForProperties = kPrintFieldIndex,
+    kForTransitions = kPrintAttributes,
+    kPrintFull = -1,
+  };
+  void PrintAsSlowTo(std::ostream& out);
+  void PrintAsFastTo(std::ostream& out, PrintMode mode = kPrintFull);
+
+ private:
+  PropertyDetails(int value, int pointer) {
+    value_ = DescriptorPointer::update(value, pointer);
+  }
+  PropertyDetails(int value, Representation representation) {
+    value_ = RepresentationField::update(value,
+                                         EncodeRepresentation(representation));
+  }
+  PropertyDetails(int value, PropertyConstness constness) {
+    value_ = ConstnessField::update(value, constness);
+  }
+  PropertyDetails(int value, PropertyAttributes attributes) {
+    value_ = AttributesField::update(value, attributes);
+  }
+
+  uint32_t value_;
+};
+
+// kField location is more general than kDescriptor, kDescriptor generalizes
+// only to itself.
+inline bool IsGeneralizableTo(PropertyLocation a, PropertyLocation b) {
+  return b == kField || a == kDescriptor;
+}
+
+// PropertyConstness::kMutable constness is more general than
+// VariableMode::kConst, VariableMode::kConst generalizes only to itself.
+inline bool IsGeneralizableTo(PropertyConstness a, PropertyConstness b) {
+  return b == PropertyConstness::kMutable || a == PropertyConstness::kConst;
+}
+
+inline PropertyConstness GeneralizeConstness(PropertyConstness a,
+                                             PropertyConstness b) {
+  return a == PropertyConstness::kMutable ? PropertyConstness::kMutable : b;
+}
+
+V8_EXPORT_PRIVATE std::ostream& operator<<(
+    std::ostream& os, const PropertyAttributes& attributes);
+V8_EXPORT_PRIVATE std::ostream& operator<<(std::ostream& os,
+                                           PropertyConstness constness);
+}  // namespace internal
+}  // namespace v8
+
+#endif  // V8_OBJECTS_PROPERTY_DETAILS_H_