Merge up to 8597 to experimental/gc from the bleeding edge.

src/macros.py

Index: src/macros.py
===================================================================
--- src/macros.py	(revision 8618)
+++ src/macros.py	(working copy)
@@ -38,12 +38,13 @@
 const SETTER = 1;
 
 # These definitions must match the index of the properties in objects.h.
-const kApiTagOffset               = 0;
-const kApiPropertyListOffset      = 1;
-const kApiSerialNumberOffset      = 2;
-const kApiConstructorOffset       = 2;
-const kApiPrototypeTemplateOffset = 5;
-const kApiParentTemplateOffset    = 6;
+const kApiTagOffset                 = 0;
+const kApiPropertyListOffset        = 1;
+const kApiSerialNumberOffset        = 2;
+const kApiConstructorOffset         = 2;
+const kApiPrototypeTemplateOffset   = 5;
+const kApiParentTemplateOffset      = 6;
+const kApiPrototypeAttributesOffset = 15;
 
 const NO_HINT     = 0;
 const NUMBER_HINT = 1;
@@ -128,6 +129,7 @@
 macro TO_STRING_INLINE(arg) = (IS_STRING(%IS_VAR(arg)) ? arg : NonStringToString(arg));
 macro TO_NUMBER_INLINE(arg) = (IS_NUMBER(%IS_VAR(arg)) ? arg : NonNumberToNumber(arg));
 macro TO_OBJECT_INLINE(arg) = (IS_SPEC_OBJECT(%IS_VAR(arg)) ? arg : ToObject(arg));
+macro JSON_NUMBER_TO_STRING(arg) = ((%_IsSmi(%IS_VAR(arg)) || arg - arg == 0) ? %_NumberToString(arg) : "null");
 
 # Macros implemented in Python.
 python macro CHAR_CODE(str) = ord(str[1]);