Put direct code pointers into JSFunction objects. This is a first step...

src/objects-inl.h

Index: src/objects-inl.h
===================================================================
--- src/objects-inl.h	(revision 5232)
+++ src/objects-inl.h	(working copy)
@@ -2694,12 +2694,14 @@
 
 
 Code* JSFunction::code() {
-  return shared()->code();
+  return Code::cast(READ_FIELD(this, kCodeOffset));
 }
 
 
 void JSFunction::set_code(Code* value) {
-  shared()->set_code(value);
+  // Skip the write barrier because code is never in new space.
+  ASSERT(!Heap::InNewSpace(value));
+  WRITE_FIELD(this, kCodeOffset, value);
 }
 
 
@@ -2771,7 +2773,7 @@
 
 
 bool JSFunction::is_compiled() {
-  return shared()->is_compiled();
+  return code()->kind() != Code::STUB;
 }