Pretenure JSON graph if the input string is larger than 100*1024 chars.

src/json-parser.h

Index: src/json-parser.h
diff --git a/src/json-parser.h b/src/json-parser.h
index 40116fa59ab9594c578d5467ac5330cf3509dd37..d088d038b6e6d2f09cf67ca5cdbdd40b5a2d3b13 100644
--- a/src/json-parser.h
+++ b/src/json-parser.h
@@ -161,6 +161,7 @@ class JsonParser BASE_EMBEDDED {
   int source_length_;
   Handle<SeqAsciiString> seq_source_;
 
+  PretenureFlag tenure_;

[Michael Starzinger, 2012/10/22 16:44:28]

Let's call that "pretenure_" to be in line with the rest of the code-base.

[Toon Verwaest, 2012/10/23 08:05:57]

Done.

   Isolate* isolate_;
   Factory* factory_;
   Handle<JSFunction> object_constructor_;
@@ -180,6 +181,8 @@ Handle<Object> JsonParser<seq_ascii>::ParseJson(Handle<String> source,
   FlattenString(source);
   source_ = source;
   source_length_ = source_->length();
+  static const int kJsonAllocatePretenured = 100 * 1024;

[Michael Starzinger, 2012/10/22 16:44:28]

Can we move this constant out into the JsonParser class. And I would rename it
to kPretenureThreshold or something like that.

[Toon Verwaest, 2012/10/23 08:05:57]

Done.

+  tenure_ = (source_length_ >= kJsonAllocatePretenured) ? TENURED : NOT_TENURED;
 
   // Optimized fast case where we only have ASCII characters.
   if (seq_ascii) {
@@ -281,7 +284,7 @@ template <bool seq_ascii>
 Handle<Object> JsonParser<seq_ascii>::ParseJsonObject() {
   Handle<Object> prototype;
   Handle<JSObject> json_object =
-      factory()->NewJSObject(object_constructor());
+      factory()->NewJSObject(object_constructor(), tenure_);
   ASSERT_EQ(c0_, '{');
 
   AdvanceSkipWhitespace();
@@ -365,11 +368,12 @@ Handle<Object> JsonParser<seq_ascii>::ParseJsonArray() {
   AdvanceSkipWhitespace();
   // Allocate a fixed array with all the elements.
   Handle<FixedArray> fast_elements =
-      factory()->NewFixedArray(elements.length());
+      factory()->NewFixedArray(elements.length(), tenure_);
   for (int i = 0, n = elements.length(); i < n; i++) {
     fast_elements->set(i, *elements[i]);
   }
-  return factory()->NewJSArrayWithElements(fast_elements);
+  return factory()->NewJSArrayWithElements(
+      fast_elements, FAST_ELEMENTS, tenure_);
 }
 
 
@@ -436,7 +440,7 @@ Handle<Object> JsonParser<seq_ascii>::ParseJsonNumber() {
     buffer.Dispose();
   }
   SkipWhitespace();
-  return factory()->NewNumber(number);
+  return factory()->NewNumber(number, tenure_);
 }
 
 
@@ -454,16 +458,22 @@ inline void SeqStringSet(Handle<SeqAsciiString> seq_str, int i, uc32 c) {
 }
 
 template <typename StringType>
-inline Handle<StringType> NewRawString(Factory* factory, int length);
+inline Handle<StringType> NewRawString(Factory* factory,
+                                       int length,
+                                       PretenureFlag tenure);

[Michael Starzinger, 2012/10/22 16:44:28]

Call the third argument "pretenure".

[Toon Verwaest, 2012/10/23 08:05:57]

Done.

 
 template <>
-inline Handle<SeqTwoByteString> NewRawString(Factory* factory, int length) {
-  return factory->NewRawTwoByteString(length, NOT_TENURED);
+inline Handle<SeqTwoByteString> NewRawString(Factory* factory,
+                                             int length,
+                                             PretenureFlag tenure) {

[Michael Starzinger, 2012/10/22 16:44:28]

Likewise.

[Toon Verwaest, 2012/10/23 08:05:57]

Done.

+  return factory->NewRawTwoByteString(length, tenure);
 }
 
 template <>
-inline Handle<SeqAsciiString> NewRawString(Factory* factory, int length) {
-  return factory->NewRawAsciiString(length, NOT_TENURED);
+inline Handle<SeqAsciiString> NewRawString(Factory* factory,
+                                           int length,
+                                           PretenureFlag tenure) {

[Michael Starzinger, 2012/10/22 16:44:28]

Likewise.

[Toon Verwaest, 2012/10/23 08:05:57]

Done.

+  return factory->NewRawAsciiString(length, tenure);
 }
 
 
@@ -477,7 +487,8 @@ Handle<String> JsonParser<seq_ascii>::SlowScanJsonString(
   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>(factory(), length);
+  Handle<StringType> seq_str =
+      NewRawString<StringType>(factory(), length, tenure_);
   // Copy prefix into seq_str.
   SinkChar* dest = seq_str->GetChars();
   String::WriteToFlat(*prefix, dest, start, end);
@@ -656,10 +667,10 @@ Handle<String> JsonParser<seq_ascii>::ScanJsonString() {
   Handle<String> result;
   if (seq_ascii && is_symbol) {
     result = factory()->LookupAsciiSymbol(seq_source_,
-                                                     beg_pos,
-                                                     length);
+                                          beg_pos,

[Michael Starzinger, 2012/10/22 16:44:28]

Indentation seems off.

[Toon Verwaest, 2012/10/23 08:05:57]

Seems fine here.

On 2012/10/22 16:44:28, Michael Starzinger wrote:

+                                          length);
   } else {
-    result = factory()->NewRawAsciiString(length);
+    result = factory()->NewRawAsciiString(length, tenure_);
     char* dest = SeqAsciiString::cast(*result)->GetChars();
     String::WriteToFlat(*source_, dest, beg_pos, position_);
   }