Upgrade V8 to version 4.9.385.28
https://chromium.googlesource.com/v8/v8/+/4.9.385.28
FPIIM-449
Change-Id: I4b2e74289d4bf3667f2f3dc8aa2e541f63e26eb4
diff --git a/src/parsing/json-parser.h b/src/parsing/json-parser.h
new file mode 100644
index 0000000..e23c733
--- /dev/null
+++ b/src/parsing/json-parser.h
@@ -0,0 +1,842 @@
+// Copyright 2011 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_PARSING_JSON_PARSER_H_
+#define V8_PARSING_JSON_PARSER_H_
+
+#include "src/char-predicates.h"
+#include "src/conversions.h"
+#include "src/debug/debug.h"
+#include "src/factory.h"
+#include "src/messages.h"
+#include "src/parsing/scanner.h"
+#include "src/parsing/token.h"
+#include "src/transitions.h"
+#include "src/types.h"
+
+namespace v8 {
+namespace internal {
+
+enum ParseElementResult { kElementFound, kElementNotFound, kNullHandle };
+
+
+// A simple json parser.
+template <bool seq_one_byte>
+class JsonParser BASE_EMBEDDED {
+ public:
+ MUST_USE_RESULT static MaybeHandle<Object> Parse(Handle<String> source) {
+ return JsonParser(source).ParseJson();
+ }
+
+ static const int kEndOfString = -1;
+
+ private:
+ explicit JsonParser(Handle<String> source)
+ : source_(source),
+ source_length_(source->length()),
+ isolate_(source->map()->GetHeap()->isolate()),
+ factory_(isolate_->factory()),
+ object_constructor_(isolate_->native_context()->object_function(),
+ isolate_),
+ position_(-1) {
+ source_ = String::Flatten(source_);
+ pretenure_ = (source_length_ >= kPretenureTreshold) ? TENURED : NOT_TENURED;
+
+ // Optimized fast case where we only have Latin1 characters.
+ if (seq_one_byte) {
+ seq_source_ = Handle<SeqOneByteString>::cast(source_);
+ }
+ }
+
+ // Parse a string containing a single JSON value.
+ MaybeHandle<Object> ParseJson();
+
+ inline void Advance() {
+ position_++;
+ if (position_ >= source_length_) {
+ c0_ = kEndOfString;
+ } else if (seq_one_byte) {
+ c0_ = seq_source_->SeqOneByteStringGet(position_);
+ } else {
+ c0_ = source_->Get(position_);
+ }
+ }
+
+ // The JSON lexical grammar is specified in the ECMAScript 5 standard,
+ // section 15.12.1.1. The only allowed whitespace characters between tokens
+ // are tab, carriage-return, newline and space.
+
+ inline void AdvanceSkipWhitespace() {
+ do {
+ Advance();
+ } while (c0_ == ' ' || c0_ == '\t' || c0_ == '\n' || c0_ == '\r');
+ }
+
+ inline void SkipWhitespace() {
+ while (c0_ == ' ' || c0_ == '\t' || c0_ == '\n' || c0_ == '\r') {
+ Advance();
+ }
+ }
+
+ inline uc32 AdvanceGetChar() {
+ Advance();
+ return c0_;
+ }
+
+ // Checks that current charater is c.
+ // If so, then consume c and skip whitespace.
+ inline bool MatchSkipWhiteSpace(uc32 c) {
+ if (c0_ == c) {
+ AdvanceSkipWhitespace();
+ return true;
+ }
+ return false;
+ }
+
+ // A JSON string (production JSONString) is subset of valid JavaScript string
+ // literals. The string must only be double-quoted (not single-quoted), and
+ // the only allowed backslash-escapes are ", /, \, b, f, n, r, t and
+ // four-digit hex escapes (uXXXX). Any other use of backslashes is invalid.
+ Handle<String> ParseJsonString() {
+ return ScanJsonString<false>();
+ }
+
+ bool ParseJsonString(Handle<String> expected) {
+ int length = expected->length();
+ if (source_->length() - position_ - 1 > length) {
+ DisallowHeapAllocation no_gc;
+ String::FlatContent content = expected->GetFlatContent();
+ if (content.IsOneByte()) {
+ DCHECK_EQ('"', c0_);
+ const uint8_t* input_chars = seq_source_->GetChars() + position_ + 1;
+ const uint8_t* expected_chars = content.ToOneByteVector().start();
+ for (int i = 0; i < length; i++) {
+ uint8_t c0 = input_chars[i];
+ if (c0 != expected_chars[i] || c0 == '"' || c0 < 0x20 || c0 == '\\') {
+ return false;
+ }
+ }
+ if (input_chars[length] == '"') {
+ position_ = position_ + length + 1;
+ AdvanceSkipWhitespace();
+ return true;
+ }
+ }
+ }
+ return false;
+ }
+
+ Handle<String> ParseJsonInternalizedString() {
+ return ScanJsonString<true>();
+ }
+
+ template <bool is_internalized>
+ Handle<String> ScanJsonString();
+ // Creates a new string and copies prefix[start..end] into the beginning
+ // of it. Then scans the rest of the string, adding characters after the
+ // prefix. Called by ScanJsonString when reaching a '\' or non-Latin1 char.
+ template <typename StringType, typename SinkChar>
+ Handle<String> SlowScanJsonString(Handle<String> prefix, int start, int end);
+
+ // A JSON number (production JSONNumber) is a subset of the valid JavaScript
+ // decimal number literals.
+ // It includes an optional minus sign, must have at least one
+ // digit before and after a decimal point, may not have prefixed zeros (unless
+ // the integer part is zero), and may include an exponent part (e.g., "e-10").
+ // Hexadecimal and octal numbers are not allowed.
+ Handle<Object> ParseJsonNumber();
+
+ // Parse a single JSON value from input (grammar production JSONValue).
+ // A JSON value is either a (double-quoted) string literal, a number literal,
+ // one of "true", "false", or "null", or an object or array literal.
+ Handle<Object> ParseJsonValue();
+
+ // Parse a JSON object literal (grammar production JSONObject).
+ // An object literal is a squiggly-braced and comma separated sequence
+ // (possibly empty) of key/value pairs, where the key is a JSON string
+ // literal, the value is a JSON value, and the two are separated by a colon.
+ // A JSON array doesn't allow numbers and identifiers as keys, like a
+ // JavaScript array.
+ Handle<Object> ParseJsonObject();
+
+ // Helper for ParseJsonObject. Parses the form "123": obj, which is recorded
+ // as an element, not a property.
+ ParseElementResult ParseElement(Handle<JSObject> json_object);
+
+ // Parses a JSON array literal (grammar production JSONArray). An array
+ // literal is a square-bracketed and comma separated sequence (possibly empty)
+ // of JSON values.
+ // A JSON array doesn't allow leaving out values from the sequence, nor does
+ // it allow a terminal comma, like a JavaScript array does.
+ Handle<Object> ParseJsonArray();
+
+
+ // Mark that a parsing error has happened at the current token, and
+ // return a null handle. Primarily for readability.
+ inline Handle<Object> ReportUnexpectedCharacter() {
+ return Handle<Object>::null();
+ }
+
+ inline Isolate* isolate() { return isolate_; }
+ inline Factory* factory() { return factory_; }
+ inline Handle<JSFunction> object_constructor() { return object_constructor_; }
+
+ static const int kInitialSpecialStringLength = 32;
+ static const int kPretenureTreshold = 100 * 1024;
+
+
+ private:
+ Zone* zone() { return &zone_; }
+
+ void CommitStateToJsonObject(Handle<JSObject> json_object, Handle<Map> map,
+ ZoneList<Handle<Object> >* properties);
+
+ Handle<String> source_;
+ int source_length_;
+ Handle<SeqOneByteString> seq_source_;
+
+ PretenureFlag pretenure_;
+ Isolate* isolate_;
+ Factory* factory_;
+ Zone zone_;
+ Handle<JSFunction> object_constructor_;
+ uc32 c0_;
+ int position_;
+};
+
+template <bool seq_one_byte>
+MaybeHandle<Object> JsonParser<seq_one_byte>::ParseJson() {
+ // Advance to the first character (possibly EOS)
+ AdvanceSkipWhitespace();
+ Handle<Object> result = ParseJsonValue();
+ if (result.is_null() || c0_ != kEndOfString) {
+ // Some exception (for example stack overflow) is already pending.
+ if (isolate_->has_pending_exception()) return Handle<Object>::null();
+
+ // Parse failed. Current character is the unexpected token.
+ Factory* factory = this->factory();
+ MessageTemplate::Template message;
+ Handle<String> argument;
+
+ switch (c0_) {
+ case kEndOfString:
+ message = MessageTemplate::kUnexpectedEOS;
+ break;
+ case '-':
+ case '0':
+ case '1':
+ case '2':
+ case '3':
+ case '4':
+ case '5':
+ case '6':
+ case '7':
+ case '8':
+ case '9':
+ message = MessageTemplate::kUnexpectedTokenNumber;
+ break;
+ case '"':
+ message = MessageTemplate::kUnexpectedTokenString;
+ break;
+ default:
+ message = MessageTemplate::kUnexpectedToken;
+ argument = factory->LookupSingleCharacterStringFromCode(c0_);
+ break;
+ }
+
+ Handle<Script> script(factory->NewScript(source_));
+ // We should sent compile error event because we compile JSON object in
+ // separated source file.
+ isolate()->debug()->OnCompileError(script);
+ MessageLocation location(script, position_, position_ + 1);
+ Handle<Object> error = factory->NewSyntaxError(message, argument);
+ return isolate()->template Throw<Object>(error, &location);
+ }
+ return result;
+}
+
+
+// Parse any JSON value.
+template <bool seq_one_byte>
+Handle<Object> JsonParser<seq_one_byte>::ParseJsonValue() {
+ StackLimitCheck stack_check(isolate_);
+ if (stack_check.HasOverflowed()) {
+ isolate_->StackOverflow();
+ return Handle<Object>::null();
+ }
+
+ if (stack_check.InterruptRequested()) {
+ ExecutionAccess access(isolate_);
+ // Avoid blocking GC in long running parser (v8:3974).
+ isolate_->stack_guard()->HandleGCInterrupt();
+ }
+
+ if (c0_ == '"') return ParseJsonString();
+ if ((c0_ >= '0' && c0_ <= '9') || c0_ == '-') return ParseJsonNumber();
+ if (c0_ == '{') return ParseJsonObject();
+ if (c0_ == '[') return ParseJsonArray();
+ if (c0_ == 'f') {
+ if (AdvanceGetChar() == 'a' && AdvanceGetChar() == 'l' &&
+ AdvanceGetChar() == 's' && AdvanceGetChar() == 'e') {
+ AdvanceSkipWhitespace();
+ return factory()->false_value();
+ }
+ return ReportUnexpectedCharacter();
+ }
+ if (c0_ == 't') {
+ if (AdvanceGetChar() == 'r' && AdvanceGetChar() == 'u' &&
+ AdvanceGetChar() == 'e') {
+ AdvanceSkipWhitespace();
+ return factory()->true_value();
+ }
+ return ReportUnexpectedCharacter();
+ }
+ if (c0_ == 'n') {
+ if (AdvanceGetChar() == 'u' && AdvanceGetChar() == 'l' &&
+ AdvanceGetChar() == 'l') {
+ AdvanceSkipWhitespace();
+ return factory()->null_value();
+ }
+ return ReportUnexpectedCharacter();
+ }
+ return ReportUnexpectedCharacter();
+}
+
+
+template <bool seq_one_byte>
+ParseElementResult JsonParser<seq_one_byte>::ParseElement(
+ Handle<JSObject> json_object) {
+ uint32_t index = 0;
+ // Maybe an array index, try to parse it.
+ if (c0_ == '0') {
+ // With a leading zero, the string has to be "0" only to be an index.
+ Advance();
+ } else {
+ do {
+ int d = c0_ - '0';
+ if (index > 429496729U - ((d + 3) >> 3)) break;
+ index = (index * 10) + d;
+ Advance();
+ } while (IsDecimalDigit(c0_));
+ }
+
+ if (c0_ == '"') {
+ // Successfully parsed index, parse and store element.
+ AdvanceSkipWhitespace();
+
+ if (c0_ == ':') {
+ AdvanceSkipWhitespace();
+ Handle<Object> value = ParseJsonValue();
+ if (!value.is_null()) {
+ JSObject::SetOwnElementIgnoreAttributes(json_object, index, value, NONE)
+ .Assert();
+ return kElementFound;
+ } else {
+ return kNullHandle;
+ }
+ }
+ }
+ return kElementNotFound;
+}
+
+// Parse a JSON object. Position must be right at '{'.
+template <bool seq_one_byte>
+Handle<Object> JsonParser<seq_one_byte>::ParseJsonObject() {
+ HandleScope scope(isolate());
+ Handle<JSObject> json_object =
+ factory()->NewJSObject(object_constructor(), pretenure_);
+ Handle<Map> map(json_object->map());
+ int descriptor = 0;
+ ZoneList<Handle<Object> > properties(8, zone());
+ DCHECK_EQ(c0_, '{');
+
+ bool transitioning = true;
+
+ AdvanceSkipWhitespace();
+ if (c0_ != '}') {
+ do {
+ if (c0_ != '"') return ReportUnexpectedCharacter();
+
+ int start_position = position_;
+ Advance();
+
+ if (IsDecimalDigit(c0_)) {
+ ParseElementResult element_result = ParseElement(json_object);
+ if (element_result == kNullHandle) return Handle<Object>::null();
+ if (element_result == kElementFound) continue;
+ }
+ // Not an index, fallback to the slow path.
+
+ position_ = start_position;
+#ifdef DEBUG
+ c0_ = '"';
+#endif
+
+ Handle<String> key;
+ Handle<Object> value;
+
+ // Try to follow existing transitions as long as possible. Once we stop
+ // transitioning, no transition can be found anymore.
+ DCHECK(transitioning);
+ // First check whether there is a single expected transition. If so, try
+ // to parse it first.
+ bool follow_expected = false;
+ Handle<Map> target;
+ if (seq_one_byte) {
+ key = TransitionArray::ExpectedTransitionKey(map);
+ follow_expected = !key.is_null() && ParseJsonString(key);
+ }
+ // If the expected transition hits, follow it.
+ if (follow_expected) {
+ target = TransitionArray::ExpectedTransitionTarget(map);
+ } else {
+ // If the expected transition failed, parse an internalized string and
+ // try to find a matching transition.
+ key = ParseJsonInternalizedString();
+ if (key.is_null()) return ReportUnexpectedCharacter();
+
+ target = TransitionArray::FindTransitionToField(map, key);
+ // If a transition was found, follow it and continue.
+ transitioning = !target.is_null();
+ }
+ if (c0_ != ':') return ReportUnexpectedCharacter();
+
+ AdvanceSkipWhitespace();
+ value = ParseJsonValue();
+ if (value.is_null()) return ReportUnexpectedCharacter();
+
+ if (transitioning) {
+ PropertyDetails details =
+ target->instance_descriptors()->GetDetails(descriptor);
+ Representation expected_representation = details.representation();
+
+ if (value->FitsRepresentation(expected_representation)) {
+ if (expected_representation.IsHeapObject() &&
+ !target->instance_descriptors()
+ ->GetFieldType(descriptor)
+ ->NowContains(value)) {
+ Handle<HeapType> value_type(
+ value->OptimalType(isolate(), expected_representation));
+ Map::GeneralizeFieldType(target, descriptor,
+ expected_representation, value_type);
+ }
+ DCHECK(target->instance_descriptors()
+ ->GetFieldType(descriptor)
+ ->NowContains(value));
+ properties.Add(value, zone());
+ map = target;
+ descriptor++;
+ continue;
+ } else {
+ transitioning = false;
+ }
+ }
+
+ DCHECK(!transitioning);
+
+ // Commit the intermediate state to the object and stop transitioning.
+ CommitStateToJsonObject(json_object, map, &properties);
+
+ JSObject::DefinePropertyOrElementIgnoreAttributes(json_object, key, value)
+ .Check();
+ } while (transitioning && MatchSkipWhiteSpace(','));
+
+ // If we transitioned until the very end, transition the map now.
+ if (transitioning) {
+ CommitStateToJsonObject(json_object, map, &properties);
+ } else {
+ while (MatchSkipWhiteSpace(',')) {
+ HandleScope local_scope(isolate());
+ if (c0_ != '"') return ReportUnexpectedCharacter();
+
+ int start_position = position_;
+ Advance();
+
+ if (IsDecimalDigit(c0_)) {
+ ParseElementResult element_result = ParseElement(json_object);
+ if (element_result == kNullHandle) return Handle<Object>::null();
+ if (element_result == kElementFound) continue;
+ }
+ // Not an index, fallback to the slow path.
+
+ position_ = start_position;
+#ifdef DEBUG
+ c0_ = '"';
+#endif
+
+ Handle<String> key;
+ Handle<Object> value;
+
+ key = ParseJsonInternalizedString();
+ if (key.is_null() || c0_ != ':') return ReportUnexpectedCharacter();
+
+ AdvanceSkipWhitespace();
+ value = ParseJsonValue();
+ if (value.is_null()) return ReportUnexpectedCharacter();
+
+ JSObject::DefinePropertyOrElementIgnoreAttributes(json_object, key,
+ value).Check();
+ }
+ }
+
+ if (c0_ != '}') {
+ return ReportUnexpectedCharacter();
+ }
+ }
+ AdvanceSkipWhitespace();
+ return scope.CloseAndEscape(json_object);
+}
+
+
+template <bool seq_one_byte>
+void JsonParser<seq_one_byte>::CommitStateToJsonObject(
+ Handle<JSObject> json_object, Handle<Map> map,
+ ZoneList<Handle<Object> >* properties) {
+ JSObject::AllocateStorageForMap(json_object, map);
+ DCHECK(!json_object->map()->is_dictionary_map());
+
+ DisallowHeapAllocation no_gc;
+
+ int length = properties->length();
+ for (int i = 0; i < length; i++) {
+ Handle<Object> value = (*properties)[i];
+ json_object->WriteToField(i, *value);
+ }
+}
+
+
+// Parse a JSON array. Position must be right at '['.
+template <bool seq_one_byte>
+Handle<Object> JsonParser<seq_one_byte>::ParseJsonArray() {
+ HandleScope scope(isolate());
+ ZoneList<Handle<Object> > elements(4, zone());
+ DCHECK_EQ(c0_, '[');
+
+ AdvanceSkipWhitespace();
+ if (c0_ != ']') {
+ do {
+ Handle<Object> element = ParseJsonValue();
+ if (element.is_null()) return ReportUnexpectedCharacter();
+ elements.Add(element, zone());
+ } while (MatchSkipWhiteSpace(','));
+ if (c0_ != ']') {
+ return ReportUnexpectedCharacter();
+ }
+ }
+ AdvanceSkipWhitespace();
+ // Allocate a fixed array with all the elements.
+ Handle<FixedArray> fast_elements =
+ factory()->NewFixedArray(elements.length(), pretenure_);
+ for (int i = 0, n = elements.length(); i < n; i++) {
+ fast_elements->set(i, *elements[i]);
+ }
+ Handle<Object> json_array = factory()->NewJSArrayWithElements(
+ fast_elements, FAST_ELEMENTS, Strength::WEAK, pretenure_);
+ return scope.CloseAndEscape(json_array);
+}
+
+
+template <bool seq_one_byte>
+Handle<Object> JsonParser<seq_one_byte>::ParseJsonNumber() {
+ bool negative = false;
+ int beg_pos = position_;
+ if (c0_ == '-') {
+ Advance();
+ negative = true;
+ }
+ if (c0_ == '0') {
+ Advance();
+ // Prefix zero is only allowed if it's the only digit before
+ // a decimal point or exponent.
+ if (IsDecimalDigit(c0_)) return ReportUnexpectedCharacter();
+ } else {
+ int i = 0;
+ int digits = 0;
+ if (c0_ < '1' || c0_ > '9') return ReportUnexpectedCharacter();
+ do {
+ i = i * 10 + c0_ - '0';
+ digits++;
+ Advance();
+ } while (IsDecimalDigit(c0_));
+ if (c0_ != '.' && c0_ != 'e' && c0_ != 'E' && digits < 10) {
+ SkipWhitespace();
+ return Handle<Smi>(Smi::FromInt((negative ? -i : i)), isolate());
+ }
+ }
+ if (c0_ == '.') {
+ Advance();
+ if (!IsDecimalDigit(c0_)) return ReportUnexpectedCharacter();
+ do {
+ Advance();
+ } while (IsDecimalDigit(c0_));
+ }
+ if (AsciiAlphaToLower(c0_) == 'e') {
+ Advance();
+ if (c0_ == '-' || c0_ == '+') Advance();
+ if (!IsDecimalDigit(c0_)) return ReportUnexpectedCharacter();
+ do {
+ Advance();
+ } while (IsDecimalDigit(c0_));
+ }
+ int length = position_ - beg_pos;
+ double number;
+ if (seq_one_byte) {
+ Vector<const uint8_t> chars(seq_source_->GetChars() + beg_pos, length);
+ number = StringToDouble(isolate()->unicode_cache(), chars,
+ NO_FLAGS, // Hex, octal or trailing junk.
+ std::numeric_limits<double>::quiet_NaN());
+ } else {
+ Vector<uint8_t> buffer = Vector<uint8_t>::New(length);
+ String::WriteToFlat(*source_, buffer.start(), beg_pos, position_);
+ Vector<const uint8_t> result =
+ Vector<const uint8_t>(buffer.start(), length);
+ number = StringToDouble(isolate()->unicode_cache(),
+ result,
+ NO_FLAGS, // Hex, octal or trailing junk.
+ 0.0);
+ buffer.Dispose();
+ }
+ SkipWhitespace();
+ return factory()->NewNumber(number, pretenure_);
+}
+
+
+template <typename StringType>
+inline void SeqStringSet(Handle<StringType> seq_str, int i, uc32 c);
+
+template <>
+inline void SeqStringSet(Handle<SeqTwoByteString> seq_str, int i, uc32 c) {
+ seq_str->SeqTwoByteStringSet(i, c);
+}
+
+template <>
+inline void SeqStringSet(Handle<SeqOneByteString> seq_str, int i, uc32 c) {
+ seq_str->SeqOneByteStringSet(i, c);
+}
+
+template <typename StringType>
+inline Handle<StringType> NewRawString(Factory* factory,
+ int length,
+ PretenureFlag pretenure);
+
+template <>
+inline Handle<SeqTwoByteString> NewRawString(Factory* factory,
+ int length,
+ PretenureFlag pretenure) {
+ return factory->NewRawTwoByteString(length, pretenure).ToHandleChecked();
+}
+
+template <>
+inline Handle<SeqOneByteString> NewRawString(Factory* factory,
+ int length,
+ PretenureFlag pretenure) {
+ return factory->NewRawOneByteString(length, pretenure).ToHandleChecked();
+}
+
+
+// Scans the rest of a JSON string starting from position_ and writes
+// prefix[start..end] along with the scanned characters into a
+// sequential string of type StringType.
+template <bool seq_one_byte>
+template <typename StringType, typename SinkChar>
+Handle<String> JsonParser<seq_one_byte>::SlowScanJsonString(
+ Handle<String> prefix, int start, int end) {
+ int count = end - start;
+ int max_length = count + source_length_ - position_;
+ int length = Min(max_length, Max(kInitialSpecialStringLength, 2 * count));
+ Handle<StringType> seq_string =
+ NewRawString<StringType>(factory(), length, pretenure_);
+ // Copy prefix into seq_str.
+ SinkChar* dest = seq_string->GetChars();
+ String::WriteToFlat(*prefix, dest, start, end);
+
+ while (c0_ != '"') {
+ // Check for control character (0x00-0x1f) or unterminated string (<0).
+ if (c0_ < 0x20) return Handle<String>::null();
+ if (count >= length) {
+ // We need to create a longer sequential string for the result.
+ return SlowScanJsonString<StringType, SinkChar>(seq_string, 0, count);
+ }
+ if (c0_ != '\\') {
+ // If the sink can contain UC16 characters, or source_ contains only
+ // Latin1 characters, there's no need to test whether we can store the
+ // character. Otherwise check whether the UC16 source character can fit
+ // in the Latin1 sink.
+ if (sizeof(SinkChar) == kUC16Size || seq_one_byte ||
+ c0_ <= String::kMaxOneByteCharCode) {
+ SeqStringSet(seq_string, count++, c0_);
+ Advance();
+ } else {
+ // StringType is SeqOneByteString and we just read a non-Latin1 char.
+ return SlowScanJsonString<SeqTwoByteString, uc16>(seq_string, 0, count);
+ }
+ } else {
+ Advance(); // Advance past the \.
+ switch (c0_) {
+ case '"':
+ case '\\':
+ case '/':
+ SeqStringSet(seq_string, count++, c0_);
+ break;
+ case 'b':
+ SeqStringSet(seq_string, count++, '\x08');
+ break;
+ case 'f':
+ SeqStringSet(seq_string, count++, '\x0c');
+ break;
+ case 'n':
+ SeqStringSet(seq_string, count++, '\x0a');
+ break;
+ case 'r':
+ SeqStringSet(seq_string, count++, '\x0d');
+ break;
+ case 't':
+ SeqStringSet(seq_string, count++, '\x09');
+ break;
+ case 'u': {
+ uc32 value = 0;
+ for (int i = 0; i < 4; i++) {
+ Advance();
+ int digit = HexValue(c0_);
+ if (digit < 0) {
+ return Handle<String>::null();
+ }
+ value = value * 16 + digit;
+ }
+ if (sizeof(SinkChar) == kUC16Size ||
+ value <= String::kMaxOneByteCharCode) {
+ SeqStringSet(seq_string, count++, value);
+ break;
+ } else {
+ // StringType is SeqOneByteString and we just read a non-Latin1
+ // char.
+ position_ -= 6; // Rewind position_ to \ in \uxxxx.
+ Advance();
+ return SlowScanJsonString<SeqTwoByteString, uc16>(seq_string,
+ 0,
+ count);
+ }
+ }
+ default:
+ return Handle<String>::null();
+ }
+ Advance();
+ }
+ }
+
+ DCHECK_EQ('"', c0_);
+ // Advance past the last '"'.
+ AdvanceSkipWhitespace();
+
+ // Shrink seq_string length to count and return.
+ return SeqString::Truncate(seq_string, count);
+}
+
+
+template <bool seq_one_byte>
+template <bool is_internalized>
+Handle<String> JsonParser<seq_one_byte>::ScanJsonString() {
+ DCHECK_EQ('"', c0_);
+ Advance();
+ if (c0_ == '"') {
+ AdvanceSkipWhitespace();
+ return factory()->empty_string();
+ }
+
+ if (seq_one_byte && is_internalized) {
+ // Fast path for existing internalized strings. If the the string being
+ // parsed is not a known internalized string, contains backslashes or
+ // unexpectedly reaches the end of string, return with an empty handle.
+ uint32_t running_hash = isolate()->heap()->HashSeed();
+ int position = position_;
+ uc32 c0 = c0_;
+ do {
+ if (c0 == '\\') {
+ c0_ = c0;
+ int beg_pos = position_;
+ position_ = position;
+ return SlowScanJsonString<SeqOneByteString, uint8_t>(source_,
+ beg_pos,
+ position_);
+ }
+ if (c0 < 0x20) return Handle<String>::null();
+ running_hash = StringHasher::AddCharacterCore(running_hash,
+ static_cast<uint16_t>(c0));
+ position++;
+ if (position >= source_length_) return Handle<String>::null();
+ c0 = seq_source_->SeqOneByteStringGet(position);
+ } while (c0 != '"');
+ int length = position - position_;
+ uint32_t hash = (length <= String::kMaxHashCalcLength)
+ ? StringHasher::GetHashCore(running_hash)
+ : static_cast<uint32_t>(length);
+ Vector<const uint8_t> string_vector(
+ seq_source_->GetChars() + position_, length);
+ StringTable* string_table = isolate()->heap()->string_table();
+ uint32_t capacity = string_table->Capacity();
+ uint32_t entry = StringTable::FirstProbe(hash, capacity);
+ uint32_t count = 1;
+ Handle<String> result;
+ while (true) {
+ Object* element = string_table->KeyAt(entry);
+ if (element == isolate()->heap()->undefined_value()) {
+ // Lookup failure.
+ result = factory()->InternalizeOneByteString(
+ seq_source_, position_, length);
+ break;
+ }
+ if (element != isolate()->heap()->the_hole_value() &&
+ String::cast(element)->IsOneByteEqualTo(string_vector)) {
+ result = Handle<String>(String::cast(element), isolate());
+#ifdef DEBUG
+ uint32_t hash_field =
+ (hash << String::kHashShift) | String::kIsNotArrayIndexMask;
+ DCHECK_EQ(static_cast<int>(result->Hash()),
+ static_cast<int>(hash_field >> String::kHashShift));
+#endif
+ break;
+ }
+ entry = StringTable::NextProbe(entry, count++, capacity);
+ }
+ position_ = position;
+ // Advance past the last '"'.
+ AdvanceSkipWhitespace();
+ return result;
+ }
+
+ int beg_pos = position_;
+ // Fast case for Latin1 only without escape characters.
+ do {
+ // Check for control character (0x00-0x1f) or unterminated string (<0).
+ if (c0_ < 0x20) return Handle<String>::null();
+ if (c0_ != '\\') {
+ if (seq_one_byte || c0_ <= String::kMaxOneByteCharCode) {
+ Advance();
+ } else {
+ return SlowScanJsonString<SeqTwoByteString, uc16>(source_,
+ beg_pos,
+ position_);
+ }
+ } else {
+ return SlowScanJsonString<SeqOneByteString, uint8_t>(source_,
+ beg_pos,
+ position_);
+ }
+ } while (c0_ != '"');
+ int length = position_ - beg_pos;
+ Handle<String> result =
+ factory()->NewRawOneByteString(length, pretenure_).ToHandleChecked();
+ uint8_t* dest = SeqOneByteString::cast(*result)->GetChars();
+ String::WriteToFlat(*source_, dest, beg_pos, position_);
+
+ DCHECK_EQ('"', c0_);
+ // Advance past the last '"'.
+ AdvanceSkipWhitespace();
+ return result;
+}
+
+} // namespace internal
+} // namespace v8
+
+#endif // V8_PARSING_JSON_PARSER_H_