Dramatically speed up detailed heap snapshot generation.

src/objects-inl.h

Index: src/objects-inl.h
diff --git a/src/objects-inl.h b/src/objects-inl.h
index 01073ca7b08bd272520e1b1009d266a671411e7e..21a4bde2fd8238212574340dc1048fde89787416 100644
--- a/src/objects-inl.h
+++ b/src/objects-inl.h
@@ -1313,6 +1313,12 @@ int JSObject::GetInternalFieldCount() {
 }
 
 
+int JSObject::GetInternalFieldOffset(int index) {
+  ASSERT(index < GetInternalFieldCount() && index >= 0);
+  return GetHeaderSize() + (kPointerSize * index);
+}
+
+
 Object* JSObject::GetInternalField(int index) {
   ASSERT(index < GetInternalFieldCount() && index >= 0);
   // Internal objects do follow immediately after the header, whereas in-object
@@ -1336,6 +1342,13 @@ void JSObject::SetInternalField(int index, Object* value) {
 // Access fast-case object properties at index. The use of these routines
 // is needed to correctly distinguish between properties stored in-object and
 // properties stored in the properties array.
+int JSObject::GetFastPropertyOffset(int index) {

[Vitaly Repeshko, 2011/03/18 12:16:36]

This should be called "GetInObjectPropertyOffset". It should assert the index
does not exceed the number of inobject properties and its callers should make
sure not to trigger the assert.

[mnaganov (inactive), 2011/03/18 12:31:01]

Done.

+  // Adjust for the number of properties stored in the object.
+  index -= map()->inobject_properties();
+  return index < 0 ? map()->instance_size() + (index * kPointerSize) : -1;
+}
+
+
 Object* JSObject::FastPropertyAt(int index) {
   // Adjust for the number of properties stored in the object.
   index -= map()->inobject_properties();