Revision: 12779
Author: [email protected]
Date: Fri Oct 19 08:37:28 2012
Log: Micro-optimizing the json parser
Review URL: https://chromiumcodereview.appspot.com/11237002
http://code.google.com/p/v8/source/detail?r=12779
Modified:
/branches/bleeding_edge/src/json-parser.h
=======================================
--- /branches/bleeding_edge/src/json-parser.h Fri Oct 19 03:48:18 2012
+++ /branches/bleeding_edge/src/json-parser.h Fri Oct 19 08:37:28 2012
@@ -149,6 +149,8 @@
}
inline Isolate* isolate() { return isolate_; }
+ inline Factory* factory() { return factory_; }
+ inline Handle<JSFunction> object_constructor() { return
object_constructor_; }
inline Zone* zone() const { return zone_; }
static const int kInitialSpecialStringLength = 1024;
@@ -160,6 +162,8 @@
Handle<SeqAsciiString> seq_source_;
Isolate* isolate_;
+ Factory* factory_;
+ Handle<JSFunction> object_constructor_;
uc32 c0_;
int position_;
Zone* zone_;
@@ -169,6 +173,9 @@
Handle<Object> JsonParser<seq_ascii>::ParseJson(Handle<String> source,
Zone* zone) {
isolate_ = source->map()->GetHeap()->isolate();
+ factory_ = isolate_->factory();
+ object_constructor_ =
+ Handle<JSFunction>(isolate()->native_context()->object_function());
zone_ = zone;
FlattenString(source);
source_ = source;
@@ -188,7 +195,7 @@
// Parse failed. Current character is the unexpected token.
const char* message;
- Factory* factory = isolate()->factory();
+ Factory* factory = this->factory();
Handle<JSArray> array;
switch (c0_) {
@@ -237,52 +244,35 @@
// Parse any JSON value.
template <bool seq_ascii>
Handle<Object> JsonParser<seq_ascii>::ParseJsonValue() {
- switch (c0_) {
- case '"':
- return ParseJsonString();
- case '-':
- case '0':
- case '1':
- case '2':
- case '3':
- case '4':
- case '5':
- case '6':
- case '7':
- case '8':
- case '9':
- return ParseJsonNumber();
- case 'f':
- if (AdvanceGetChar() == 'a' && AdvanceGetChar() == 'l' &&
- AdvanceGetChar() == 's' && AdvanceGetChar() == 'e') {
- AdvanceSkipWhitespace();
- return isolate()->factory()->false_value();
- } else {
- return ReportUnexpectedCharacter();
- }
- case 't':
- if (AdvanceGetChar() == 'r' && AdvanceGetChar() == 'u' &&
- AdvanceGetChar() == 'e') {
- AdvanceSkipWhitespace();
- return isolate()->factory()->true_value();
- } else {
- return ReportUnexpectedCharacter();
- }
- case 'n':
- if (AdvanceGetChar() == 'u' && AdvanceGetChar() == 'l' &&
- AdvanceGetChar() == 'l') {
- AdvanceSkipWhitespace();
- return isolate()->factory()->null_value();
- } else {
- return ReportUnexpectedCharacter();
- }
- case '{':
- return ParseJsonObject();
- case '[':
- return ParseJsonArray();
- default:
- return ReportUnexpectedCharacter();
+ 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();
}
@@ -290,10 +280,8 @@
template <bool seq_ascii>
Handle<Object> JsonParser<seq_ascii>::ParseJsonObject() {
Handle<Object> prototype;
- Handle<JSFunction> object_constructor(
- isolate()->native_context()->object_function());
Handle<JSObject> json_object =
- isolate()->factory()->NewJSObject(object_constructor);
+ factory()->NewJSObject(object_constructor());
ASSERT_EQ(c0_, '{');
AdvanceSkipWhitespace();
@@ -377,11 +365,11 @@
AdvanceSkipWhitespace();
// Allocate a fixed array with all the elements.
Handle<FixedArray> fast_elements =
- isolate()->factory()->NewFixedArray(elements.length());
+ factory()->NewFixedArray(elements.length());
for (int i = 0, n = elements.length(); i < n; i++) {
fast_elements->set(i, *elements[i]);
}
- return isolate()->factory()->NewJSArrayWithElements(fast_elements);
+ return factory()->NewJSArrayWithElements(fast_elements);
}
@@ -448,7 +436,7 @@
buffer.Dispose();
}
SkipWhitespace();
- return isolate()->factory()->NewNumber(number);
+ return factory()->NewNumber(number);
}
@@ -489,8 +477,7 @@
int count = end - start;
int max_length = count + source_length_ - position_;
int length = Min(max_length, Max(kInitialSpecialStringLength, 2 *
count));
- Handle<StringType> seq_str =
NewRawString<StringType>(isolate()->factory(),
- length);
+ Handle<StringType> seq_str = NewRawString<StringType>(factory(), length);
// Copy prefix into seq_str.
SinkChar* dest = seq_str->GetChars();
String::WriteToFlat(*prefix, dest, start, end);
@@ -668,11 +655,11 @@
int length = position_ - beg_pos;
Handle<String> result;
if (seq_ascii && is_symbol) {
- result = isolate()->factory()->LookupAsciiSymbol(seq_source_,
+ result = factory()->LookupAsciiSymbol(seq_source_,
beg_pos,
length);
} else {
- result = isolate()->factory()->NewRawAsciiString(length);
+ result = factory()->NewRawAsciiString(length);
char* dest = SeqAsciiString::cast(*result)->GetChars();
String::WriteToFlat(*source_, dest, beg_pos, position_);
}
--
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