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// Copyright 2017 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_STRING_INL_H_
#define V8_OBJECTS_STRING_INL_H_
#include "src/common/external-pointer-inl.h"
#include "src/common/external-pointer.h"
#include "src/common/globals.h"
#include "src/handles/handles-inl.h"
#include "src/heap/factory.h"
#include "src/numbers/conversions-inl.h"
#include "src/numbers/hash-seed-inl.h"
#include "src/objects/name-inl.h"
#include "src/objects/smi-inl.h"
#include "src/objects/string-table-inl.h"
#include "src/objects/string.h"
#include "src/strings/string-hasher-inl.h"
// Has to be the last include (doesn't have include guards):
#include "src/objects/object-macros.h"
namespace v8 {
namespace internal {
int String::synchronized_length() const {
return base::AsAtomic32::Acquire_Load(
reinterpret_cast<const int32_t*>(FIELD_ADDR(*this, kLengthOffset)));
}
void String::synchronized_set_length(int value) {
base::AsAtomic32::Release_Store(
reinterpret_cast<int32_t*>(FIELD_ADDR(*this, kLengthOffset)), value);
}
TQ_OBJECT_CONSTRUCTORS_IMPL(String)
TQ_OBJECT_CONSTRUCTORS_IMPL(SeqString)
TQ_OBJECT_CONSTRUCTORS_IMPL(SeqOneByteString)
TQ_OBJECT_CONSTRUCTORS_IMPL(SeqTwoByteString)
TQ_OBJECT_CONSTRUCTORS_IMPL(InternalizedString)
TQ_OBJECT_CONSTRUCTORS_IMPL(ConsString)
TQ_OBJECT_CONSTRUCTORS_IMPL(ThinString)
TQ_OBJECT_CONSTRUCTORS_IMPL(SlicedString)
OBJECT_CONSTRUCTORS_IMPL(ExternalString, String)
OBJECT_CONSTRUCTORS_IMPL(ExternalOneByteString, ExternalString)
OBJECT_CONSTRUCTORS_IMPL(ExternalTwoByteString, ExternalString)
CAST_ACCESSOR(ExternalOneByteString)
CAST_ACCESSOR(ExternalString)
CAST_ACCESSOR(ExternalTwoByteString)
StringShape::StringShape(const String str) : type_(str.map().instance_type()) {
set_valid();
DCHECK_EQ(type_ & kIsNotStringMask, kStringTag);
}
StringShape::StringShape(Map map) : type_(map.instance_type()) {
set_valid();
DCHECK_EQ(type_ & kIsNotStringMask, kStringTag);
}
StringShape::StringShape(InstanceType t) : type_(static_cast<uint32_t>(t)) {
set_valid();
DCHECK_EQ(type_ & kIsNotStringMask, kStringTag);
}
bool StringShape::IsInternalized() {
DCHECK(valid());
STATIC_ASSERT(kNotInternalizedTag != 0);
return (type_ & (kIsNotStringMask | kIsNotInternalizedMask)) ==
(kStringTag | kInternalizedTag);
}
bool StringShape::IsCons() {
return (type_ & kStringRepresentationMask) == kConsStringTag;
}
bool StringShape::IsThin() {
return (type_ & kStringRepresentationMask) == kThinStringTag;
}
bool StringShape::IsSliced() {
return (type_ & kStringRepresentationMask) == kSlicedStringTag;
}
bool StringShape::IsIndirect() {
return (type_ & kIsIndirectStringMask) == kIsIndirectStringTag;
}
bool StringShape::IsExternal() {
return (type_ & kStringRepresentationMask) == kExternalStringTag;
}
bool StringShape::IsSequential() {
return (type_ & kStringRepresentationMask) == kSeqStringTag;
}
StringRepresentationTag StringShape::representation_tag() {
uint32_t tag = (type_ & kStringRepresentationMask);
return static_cast<StringRepresentationTag>(tag);
}
uint32_t StringShape::encoding_tag() { return type_ & kStringEncodingMask; }
uint32_t StringShape::full_representation_tag() {
return (type_ & (kStringRepresentationMask | kStringEncodingMask));
}
STATIC_ASSERT((kStringRepresentationMask | kStringEncodingMask) ==
Internals::kFullStringRepresentationMask);
STATIC_ASSERT(static_cast<uint32_t>(kStringEncodingMask) ==
Internals::kStringEncodingMask);
bool StringShape::IsSequentialOneByte() {
return full_representation_tag() == (kSeqStringTag | kOneByteStringTag);
}
bool StringShape::IsSequentialTwoByte() {
return full_representation_tag() == (kSeqStringTag | kTwoByteStringTag);
}
bool StringShape::IsExternalOneByte() {
return full_representation_tag() == (kExternalStringTag | kOneByteStringTag);
}
STATIC_ASSERT((kExternalStringTag | kOneByteStringTag) ==
Internals::kExternalOneByteRepresentationTag);
STATIC_ASSERT(v8::String::ONE_BYTE_ENCODING == kOneByteStringTag);
bool StringShape::IsExternalTwoByte() {
return full_representation_tag() == (kExternalStringTag | kTwoByteStringTag);
}
STATIC_ASSERT((kExternalStringTag | kTwoByteStringTag) ==
Internals::kExternalTwoByteRepresentationTag);
STATIC_ASSERT(v8::String::TWO_BYTE_ENCODING == kTwoByteStringTag);
template <typename TDispatcher, typename TResult, typename... TArgs>
inline TResult StringShape::DispatchToSpecificTypeWithoutCast(TArgs&&... args) {
switch (full_representation_tag()) {
case kSeqStringTag | kOneByteStringTag:
return TDispatcher::HandleSeqOneByteString(std::forward<TArgs>(args)...);
case kSeqStringTag | kTwoByteStringTag:
return TDispatcher::HandleSeqTwoByteString(std::forward<TArgs>(args)...);
case kConsStringTag | kOneByteStringTag:
case kConsStringTag | kTwoByteStringTag:
return TDispatcher::HandleConsString(std::forward<TArgs>(args)...);
case kExternalStringTag | kOneByteStringTag:
return TDispatcher::HandleExternalOneByteString(
std::forward<TArgs>(args)...);
case kExternalStringTag | kTwoByteStringTag:
return TDispatcher::HandleExternalTwoByteString(
std::forward<TArgs>(args)...);
case kSlicedStringTag | kOneByteStringTag:
case kSlicedStringTag | kTwoByteStringTag:
return TDispatcher::HandleSlicedString(std::forward<TArgs>(args)...);
case kThinStringTag | kOneByteStringTag:
case kThinStringTag | kTwoByteStringTag:
return TDispatcher::HandleThinString(std::forward<TArgs>(args)...);
default:
return TDispatcher::HandleInvalidString(std::forward<TArgs>(args)...);
}
}
// All concrete subclasses of String (leaves of the inheritance tree).
#define STRING_CLASS_TYPES(V) \
V(SeqOneByteString) \
V(SeqTwoByteString) \
V(ConsString) \
V(ExternalOneByteString) \
V(ExternalTwoByteString) \
V(SlicedString) \
V(ThinString)
template <typename TDispatcher, typename TResult, typename... TArgs>
inline TResult StringShape::DispatchToSpecificType(String str,
TArgs&&... args) {
class CastingDispatcher : public AllStatic {
public:
#define DEFINE_METHOD(Type) \
static inline TResult Handle##Type(String str, TArgs&&... args) { \
return TDispatcher::Handle##Type(Type::cast(str), \
std::forward<TArgs>(args)...); \
}
STRING_CLASS_TYPES(DEFINE_METHOD)
#undef DEFINE_METHOD
static inline TResult HandleInvalidString(String str, TArgs&&... args) {
return TDispatcher::HandleInvalidString(str,
std::forward<TArgs>(args)...);
}
};
return DispatchToSpecificTypeWithoutCast<CastingDispatcher, TResult>(
str, std::forward<TArgs>(args)...);
}
DEF_GETTER(String, IsOneByteRepresentation, bool) {
uint32_t type = map(isolate).instance_type();
return (type & kStringEncodingMask) == kOneByteStringTag;
}
DEF_GETTER(String, IsTwoByteRepresentation, bool) {
uint32_t type = map(isolate).instance_type();
return (type & kStringEncodingMask) == kTwoByteStringTag;
}
// static
bool String::IsOneByteRepresentationUnderneath(String string) {
while (true) {
uint32_t type = string.map().instance_type();
STATIC_ASSERT(kIsIndirectStringTag != 0);
STATIC_ASSERT((kIsIndirectStringMask & kStringEncodingMask) == 0);
DCHECK(string.IsFlat());
switch (type & (kIsIndirectStringMask | kStringEncodingMask)) {
case kOneByteStringTag:
return true;
case kTwoByteStringTag:
return false;
default: // Cons, sliced, thin, strings need to go deeper.
string = string.GetUnderlying();
}
}
}
uc32 FlatStringReader::Get(int index) {
if (is_one_byte_) {
return Get<uint8_t>(index);
} else {
return Get<uc16>(index);
}
}
template <typename Char>
Char FlatStringReader::Get(int index) {
DCHECK_EQ(is_one_byte_, sizeof(Char) == 1);
DCHECK(0 <= index && index <= length_);
if (sizeof(Char) == 1) {
return static_cast<Char>(static_cast<const uint8_t*>(start_)[index]);
} else {
return static_cast<Char>(static_cast<const uc16*>(start_)[index]);
}
}
template <typename Char>
class SequentialStringKey final : public StringTableKey {
public:
SequentialStringKey(const Vector<const Char>& chars, uint64_t seed,
bool convert = false)
: SequentialStringKey(StringHasher::HashSequentialString<Char>(
chars.begin(), chars.length(), seed),
chars, convert) {}
SequentialStringKey(int hash, const Vector<const Char>& chars,
bool convert = false)
: StringTableKey(hash, chars.length()),
chars_(chars),
convert_(convert) {}
bool IsMatch(String s) override {
DisallowHeapAllocation no_gc;
if (s.IsOneByteRepresentation()) {
const uint8_t* chars = s.GetChars<uint8_t>(no_gc);
return CompareChars(chars, chars_.begin(), chars_.length()) == 0;
}
const uint16_t* chars = s.GetChars<uint16_t>(no_gc);
return CompareChars(chars, chars_.begin(), chars_.length()) == 0;
}
Handle<String> AsHandle(Isolate* isolate) override {
if (sizeof(Char) == 1) {
return isolate->factory()->NewOneByteInternalizedString(
Vector<const uint8_t>::cast(chars_), hash_field());
}
return isolate->factory()->NewTwoByteInternalizedString(
Vector<const uint16_t>::cast(chars_), hash_field());
}
private:
Vector<const Char> chars_;
bool convert_;
};
using OneByteStringKey = SequentialStringKey<uint8_t>;
using TwoByteStringKey = SequentialStringKey<uint16_t>;
template <typename SeqString>
class SeqSubStringKey final : public StringTableKey {
public:
using Char = typename SeqString::Char;
// VS 2017 on official builds gives this spurious warning:
// warning C4789: buffer 'key' of size 16 bytes will be overrun; 4 bytes will
// be written starting at offset 16
// https://bugs.chromium.org/p/v8/issues/detail?id=6068
#if defined(V8_CC_MSVC)
#pragma warning(push)
#pragma warning(disable : 4789)
#endif
SeqSubStringKey(Isolate* isolate, Handle<SeqString> string, int from, int len,
bool convert = false)
: StringTableKey(0, len),
string_(string),
from_(from),
convert_(convert) {
// We have to set the hash later.
DisallowHeapAllocation no_gc;
uint32_t hash = StringHasher::HashSequentialString(
string->GetChars(no_gc) + from, len, HashSeed(isolate));
set_hash_field(hash);
DCHECK_LE(0, length());
DCHECK_LE(from_ + length(), string_->length());
DCHECK_EQ(string_->IsSeqOneByteString(), sizeof(Char) == 1);
DCHECK_EQ(string_->IsSeqTwoByteString(), sizeof(Char) == 2);
}
#if defined(V8_CC_MSVC)
#pragma warning(pop)
#endif
bool IsMatch(String string) override {
DisallowHeapAllocation no_gc;
if (string.IsOneByteRepresentation()) {
const uint8_t* data = string.GetChars<uint8_t>(no_gc);
return CompareChars(string_->GetChars(no_gc) + from_, data, length()) ==
0;
}
const uint16_t* data = string.GetChars<uint16_t>(no_gc);
return CompareChars(string_->GetChars(no_gc) + from_, data, length()) == 0;
}
Handle<String> AsHandle(Isolate* isolate) override {
if (sizeof(Char) == 1 || (sizeof(Char) == 2 && convert_)) {
Handle<SeqOneByteString> result =
isolate->factory()->AllocateRawOneByteInternalizedString(
length(), hash_field());
DisallowHeapAllocation no_gc;
CopyChars(result->GetChars(no_gc), string_->GetChars(no_gc) + from_,
length());
return result;
}
Handle<SeqTwoByteString> result =
isolate->factory()->AllocateRawTwoByteInternalizedString(length(),
hash_field());
DisallowHeapAllocation no_gc;
CopyChars(result->GetChars(no_gc), string_->GetChars(no_gc) + from_,
length());
return result;
}
private:
Handle<typename CharTraits<Char>::String> string_;
int from_;
bool convert_;
};
using SeqOneByteSubStringKey = SeqSubStringKey<SeqOneByteString>;
using SeqTwoByteSubStringKey = SeqSubStringKey<SeqTwoByteString>;
bool String::Equals(String other) {
if (other == *this) return true;
if (this->IsInternalizedString() && other.IsInternalizedString()) {
return false;
}
return SlowEquals(other);
}
bool String::Equals(Isolate* isolate, Handle<String> one, Handle<String> two) {
if (one.is_identical_to(two)) return true;
if (one->IsInternalizedString() && two->IsInternalizedString()) {
return false;
}
return SlowEquals(isolate, one, two);
}
template <typename Char>
const Char* String::GetChars(const DisallowHeapAllocation& no_gc) {
return StringShape(*this).IsExternal()
? CharTraits<Char>::ExternalString::cast(*this).GetChars()
: CharTraits<Char>::String::cast(*this).GetChars(no_gc);
}
Handle<String> String::Flatten(Isolate* isolate, Handle<String> string,
AllocationType allocation) {
if (string->IsConsString()) {
Handle<ConsString> cons = Handle<ConsString>::cast(string);
if (cons->IsFlat()) {
string = handle(cons->first(), isolate);
} else {
return SlowFlatten(isolate, cons, allocation);
}
}
if (string->IsThinString()) {
string = handle(Handle<ThinString>::cast(string)->actual(), isolate);
DCHECK(!string->IsConsString());
}
return string;
}
Handle<String> String::Flatten(OffThreadIsolate* isolate, Handle<String> string,
AllocationType allocation) {
// We should never pass non-flat strings to String::Flatten when off-thread.
DCHECK(string->IsFlat());
return string;
}
uint16_t String::Get(int index) {
DCHECK(index >= 0 && index < length());
class StringGetDispatcher : public AllStatic {
public:
#define DEFINE_METHOD(Type) \
static inline uint16_t Handle##Type(Type str, int index) { \
return str.Get(index); \
}
STRING_CLASS_TYPES(DEFINE_METHOD)
#undef DEFINE_METHOD
static inline uint16_t HandleInvalidString(String str, int index) {
UNREACHABLE();
}
};
return StringShape(*this)
.DispatchToSpecificType<StringGetDispatcher, uint16_t>(*this, index);
}
void String::Set(int index, uint16_t value) {
DCHECK(index >= 0 && index < length());
DCHECK(StringShape(*this).IsSequential());
return this->IsOneByteRepresentation()
? SeqOneByteString::cast(*this).SeqOneByteStringSet(index, value)
: SeqTwoByteString::cast(*this).SeqTwoByteStringSet(index, value);
}
bool String::IsFlat() {
if (!StringShape(*this).IsCons()) return true;
return ConsString::cast(*this).second().length() == 0;
}
String String::GetUnderlying() {
// Giving direct access to underlying string only makes sense if the
// wrapping string is already flattened.
DCHECK(this->IsFlat());
DCHECK(StringShape(*this).IsIndirect());
STATIC_ASSERT(static_cast<int>(ConsString::kFirstOffset) ==
static_cast<int>(SlicedString::kParentOffset));
STATIC_ASSERT(static_cast<int>(ConsString::kFirstOffset) ==
static_cast<int>(ThinString::kActualOffset));
const int kUnderlyingOffset = SlicedString::kParentOffset;
return TaggedField<String, kUnderlyingOffset>::load(*this);
}
template <class Visitor>
ConsString String::VisitFlat(Visitor* visitor, String string,
const int offset) {
DisallowHeapAllocation no_gc;
int slice_offset = offset;
const int length = string.length();
DCHECK(offset <= length);
while (true) {
int32_t type = string.map().instance_type();
switch (type & (kStringRepresentationMask | kStringEncodingMask)) {
case kSeqStringTag | kOneByteStringTag:
visitor->VisitOneByteString(
SeqOneByteString::cast(string).GetChars(no_gc) + slice_offset,
length - offset);
return ConsString();
case kSeqStringTag | kTwoByteStringTag:
visitor->VisitTwoByteString(
SeqTwoByteString::cast(string).GetChars(no_gc) + slice_offset,
length - offset);
return ConsString();
case kExternalStringTag | kOneByteStringTag:
visitor->VisitOneByteString(
ExternalOneByteString::cast(string).GetChars() + slice_offset,
length - offset);
return ConsString();
case kExternalStringTag | kTwoByteStringTag:
visitor->VisitTwoByteString(
ExternalTwoByteString::cast(string).GetChars() + slice_offset,
length - offset);
return ConsString();
case kSlicedStringTag | kOneByteStringTag:
case kSlicedStringTag | kTwoByteStringTag: {
SlicedString slicedString = SlicedString::cast(string);
slice_offset += slicedString.offset();
string = slicedString.parent();
continue;
}
case kConsStringTag | kOneByteStringTag:
case kConsStringTag | kTwoByteStringTag:
return ConsString::cast(string);
case kThinStringTag | kOneByteStringTag:
case kThinStringTag | kTwoByteStringTag:
string = ThinString::cast(string).actual();
continue;
default:
UNREACHABLE();
}
}
}
template <>
inline Vector<const uint8_t> String::GetCharVector(
const DisallowHeapAllocation& no_gc) {
String::FlatContent flat = GetFlatContent(no_gc);
DCHECK(flat.IsOneByte());
return flat.ToOneByteVector();
}
template <>
inline Vector<const uc16> String::GetCharVector(
const DisallowHeapAllocation& no_gc) {
String::FlatContent flat = GetFlatContent(no_gc);
DCHECK(flat.IsTwoByte());
return flat.ToUC16Vector();
}
uint32_t String::ToValidIndex(Object number) {
uint32_t index = PositiveNumberToUint32(number);
uint32_t length_value = static_cast<uint32_t>(length());
if (index > length_value) return length_value;
return index;
}
uint8_t SeqOneByteString::Get(int index) {
DCHECK(index >= 0 && index < length());
return ReadField<byte>(kHeaderSize + index * kCharSize);
}
void SeqOneByteString::SeqOneByteStringSet(int index, uint16_t value) {
DCHECK(index >= 0 && index < length() && value <= kMaxOneByteCharCode);
WriteField<byte>(kHeaderSize + index * kCharSize, static_cast<byte>(value));
}
Address SeqOneByteString::GetCharsAddress() {
return FIELD_ADDR(*this, kHeaderSize);
}
uint8_t* SeqOneByteString::GetChars(const DisallowHeapAllocation& no_gc) {
USE(no_gc);
return reinterpret_cast<uint8_t*>(GetCharsAddress());
}
Address SeqTwoByteString::GetCharsAddress() {
return FIELD_ADDR(*this, kHeaderSize);
}
uc16* SeqTwoByteString::GetChars(const DisallowHeapAllocation& no_gc) {
USE(no_gc);
return reinterpret_cast<uc16*>(FIELD_ADDR(*this, kHeaderSize));
}
uint16_t SeqTwoByteString::Get(int index) {
DCHECK(index >= 0 && index < length());
return ReadField<uint16_t>(kHeaderSize + index * kShortSize);
}
void SeqTwoByteString::SeqTwoByteStringSet(int index, uint16_t value) {
DCHECK(index >= 0 && index < length());
WriteField<uint16_t>(kHeaderSize + index * kShortSize, value);
}
// Due to ThinString rewriting, concurrent visitors need to read the length with
// acquire semantics.
inline int SeqOneByteString::AllocatedSize() {
return SizeFor(synchronized_length());
}
inline int SeqTwoByteString::AllocatedSize() {
return SizeFor(synchronized_length());
}
void SlicedString::set_parent(String parent, WriteBarrierMode mode) {
DCHECK(parent.IsSeqString() || parent.IsExternalString());
TorqueGeneratedSlicedString<SlicedString, Super>::set_parent(parent, mode);
}
Object ConsString::unchecked_first() {
return TaggedField<Object, kFirstOffset>::load(*this);
}
Object ConsString::unchecked_second() {
return RELAXED_READ_FIELD(*this, kSecondOffset);
}
DEF_GETTER(ThinString, unchecked_actual, HeapObject) {
return TaggedField<HeapObject, kActualOffset>::load(isolate, *this);
}
bool ExternalString::is_uncached() const {
InstanceType type = map().instance_type();
return (type & kUncachedExternalStringMask) == kUncachedExternalStringTag;
}
DEF_GETTER(ExternalString, resource_as_address, Address) {
ExternalPointer_t encoded_address =
ReadField<ExternalPointer_t>(kResourceOffset);
return DecodeExternalPointer(isolate, encoded_address);
}
void ExternalString::set_address_as_resource(Isolate* isolate,
Address address) {
const ExternalPointer_t encoded_address =
EncodeExternalPointer(isolate, address);
WriteField<ExternalPointer_t>(kResourceOffset, encoded_address);
if (IsExternalOneByteString()) {
ExternalOneByteString::cast(*this).update_data_cache(isolate);
} else {
ExternalTwoByteString::cast(*this).update_data_cache(isolate);
}
}
uint32_t ExternalString::resource_as_uint32() {
ExternalPointer_t encoded_address =
ReadField<ExternalPointer_t>(kResourceOffset);
return static_cast<uint32_t>(encoded_address);
}
void ExternalString::set_uint32_as_resource(Isolate* isolate, uint32_t value) {
WriteField<ExternalPointer_t>(kResourceOffset, value);
if (is_uncached()) return;
WriteField<ExternalPointer_t>(kResourceDataOffset,
EncodeExternalPointer(isolate, kNullAddress));
}
void ExternalString::DisposeResource(Isolate* isolate) {
const ExternalPointer_t encoded_address =
ReadField<ExternalPointer_t>(kResourceOffset);
v8::String::ExternalStringResourceBase* resource =
reinterpret_cast<v8::String::ExternalStringResourceBase*>(
DecodeExternalPointer(isolate, encoded_address));
// Dispose of the C++ object if it has not already been disposed.
if (resource != nullptr) {
resource->Dispose();
const ExternalPointer_t encoded_address =
EncodeExternalPointer(isolate, kNullAddress);
WriteField<ExternalPointer_t>(kResourceOffset, encoded_address);
}
}
DEF_GETTER(ExternalOneByteString, resource,
const ExternalOneByteString::Resource*) {
const ExternalPointer_t encoded_address =
ReadField<ExternalPointer_t>(kResourceOffset);
return reinterpret_cast<Resource*>(
DecodeExternalPointer(isolate, encoded_address));
}
void ExternalOneByteString::update_data_cache(Isolate* isolate) {
if (is_uncached()) return;
const ExternalPointer_t encoded_resource_data = EncodeExternalPointer(
isolate, reinterpret_cast<Address>(resource()->data()));
WriteField<ExternalPointer_t>(kResourceDataOffset, encoded_resource_data);
}
void ExternalOneByteString::SetResource(
Isolate* isolate, const ExternalOneByteString::Resource* resource) {
set_resource(isolate, resource);
size_t new_payload = resource == nullptr ? 0 : resource->length();
if (new_payload > 0) {
isolate->heap()->UpdateExternalString(*this, 0, new_payload);
}
}
void ExternalOneByteString::set_resource(
Isolate* isolate, const ExternalOneByteString::Resource* resource) {
const ExternalPointer_t encoded_address =
EncodeExternalPointer(isolate, reinterpret_cast<Address>(resource));
WriteField<ExternalPointer_t>(kResourceOffset, encoded_address);
if (resource != nullptr) update_data_cache(isolate);
}
const uint8_t* ExternalOneByteString::GetChars() {
return reinterpret_cast<const uint8_t*>(resource()->data());
}
uint8_t ExternalOneByteString::Get(int index) {
DCHECK(index >= 0 && index < length());
return GetChars()[index];
}
DEF_GETTER(ExternalTwoByteString, resource,
const ExternalTwoByteString::Resource*) {
const ExternalPointer_t encoded_address =
ReadField<ExternalPointer_t>(kResourceOffset);
return reinterpret_cast<Resource*>(
DecodeExternalPointer(isolate, encoded_address));
}
void ExternalTwoByteString::update_data_cache(Isolate* isolate) {
if (is_uncached()) return;
const ExternalPointer_t encoded_resource_data = EncodeExternalPointer(
isolate, reinterpret_cast<Address>(resource()->data()));
WriteField<ExternalPointer_t>(kResourceDataOffset, encoded_resource_data);
}
void ExternalTwoByteString::SetResource(
Isolate* isolate, const ExternalTwoByteString::Resource* resource) {
set_resource(isolate, resource);
size_t new_payload = resource == nullptr ? 0 : resource->length() * 2;
if (new_payload > 0) {
isolate->heap()->UpdateExternalString(*this, 0, new_payload);
}
}
void ExternalTwoByteString::set_resource(
Isolate* isolate, const ExternalTwoByteString::Resource* resource) {
const ExternalPointer_t encoded_address =
EncodeExternalPointer(isolate, reinterpret_cast<Address>(resource));
WriteField<ExternalPointer_t>(kResourceOffset, encoded_address);
if (resource != nullptr) update_data_cache(isolate);
}
const uint16_t* ExternalTwoByteString::GetChars() { return resource()->data(); }
uint16_t ExternalTwoByteString::Get(int index) {
DCHECK(index >= 0 && index < length());
return GetChars()[index];
}
const uint16_t* ExternalTwoByteString::ExternalTwoByteStringGetData(
unsigned start) {
return GetChars() + start;
}
int ConsStringIterator::OffsetForDepth(int depth) { return depth & kDepthMask; }
void ConsStringIterator::PushLeft(ConsString string) {
frames_[depth_++ & kDepthMask] = string;
}
void ConsStringIterator::PushRight(ConsString string) {
// Inplace update.
frames_[(depth_ - 1) & kDepthMask] = string;
}
void ConsStringIterator::AdjustMaximumDepth() {
if (depth_ > maximum_depth_) maximum_depth_ = depth_;
}
void ConsStringIterator::Pop() {
DCHECK_GT(depth_, 0);
DCHECK(depth_ <= maximum_depth_);
depth_--;
}
uint16_t StringCharacterStream::GetNext() {
DCHECK(buffer8_ != nullptr && end_ != nullptr);
// Advance cursor if needed.
if (buffer8_ == end_) HasMore();
DCHECK(buffer8_ < end_);
return is_one_byte_ ? *buffer8_++ : *buffer16_++;
}
StringCharacterStream::StringCharacterStream(String string, int offset)
: is_one_byte_(false) {
Reset(string, offset);
}
void StringCharacterStream::Reset(String string, int offset) {
buffer8_ = nullptr;
end_ = nullptr;
ConsString cons_string = String::VisitFlat(this, string, offset);
iter_.Reset(cons_string, offset);
if (!cons_string.is_null()) {
string = iter_.Next(&offset);
if (!string.is_null()) String::VisitFlat(this, string, offset);
}
}
bool StringCharacterStream::HasMore() {
if (buffer8_ != end_) return true;
int offset;
String string = iter_.Next(&offset);
DCHECK_EQ(offset, 0);
if (string.is_null()) return false;
String::VisitFlat(this, string);
DCHECK(buffer8_ != end_);
return true;
}
void StringCharacterStream::VisitOneByteString(const uint8_t* chars,
int length) {
is_one_byte_ = true;
buffer8_ = chars;
end_ = chars + length;
}
void StringCharacterStream::VisitTwoByteString(const uint16_t* chars,
int length) {
is_one_byte_ = false;
buffer16_ = chars;
end_ = reinterpret_cast<const uint8_t*>(chars + length);
}
bool String::AsArrayIndex(uint32_t* index) {
DisallowHeapAllocation no_gc;
uint32_t field = hash_field();
if (ContainsCachedArrayIndex(field)) {
*index = ArrayIndexValueBits::decode(field);
return true;
}
if (IsHashFieldComputed(field) && (field & kIsNotIntegerIndexMask)) {
return false;
}
return SlowAsArrayIndex(index);
}
bool String::AsIntegerIndex(size_t* index) {
uint32_t field = hash_field();
if (ContainsCachedArrayIndex(field)) {
*index = ArrayIndexValueBits::decode(field);
return true;
}
if (IsHashFieldComputed(field) && (field & kIsNotIntegerIndexMask)) {
return false;
}
return SlowAsIntegerIndex(index);
}
SubStringRange::SubStringRange(String string,
const DisallowHeapAllocation& no_gc, int first,
int length)
: string_(string),
first_(first),
length_(length == -1 ? string.length() : length),
no_gc_(no_gc) {}
class SubStringRange::iterator final {
public:
using iterator_category = std::forward_iterator_tag;
using difference_type = int;
using value_type = uc16;
using pointer = uc16*;
using reference = uc16&;
iterator(const iterator& other) = default;
uc16 operator*() { return content_.Get(offset_); }
bool operator==(const iterator& other) const {
return content_.UsesSameString(other.content_) && offset_ == other.offset_;
}
bool operator!=(const iterator& other) const {
return !content_.UsesSameString(other.content_) || offset_ != other.offset_;
}
iterator& operator++() {
++offset_;
return *this;
}
iterator operator++(int);
private:
friend class String;
friend class SubStringRange;
iterator(String from, int offset, const DisallowHeapAllocation& no_gc)
: content_(from.GetFlatContent(no_gc)), offset_(offset) {}
String::FlatContent content_;
int offset_;
};
SubStringRange::iterator SubStringRange::begin() {
return SubStringRange::iterator(string_, first_, no_gc_);
}
SubStringRange::iterator SubStringRange::end() {
return SubStringRange::iterator(string_, first_ + length_, no_gc_);
}
} // namespace internal
} // namespace v8
#include "src/objects/object-macros-undef.h"
#endif // V8_OBJECTS_STRING_INL_H_
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