- Get handle vtable from a static table for predefined classes.

runtime/vm/object.h

Index: runtime/vm/object.h
===================================================================
--- runtime/vm/object.h	(revision 8348)
+++ runtime/vm/object.h	(working copy)
@@ -379,6 +379,7 @@
   }
 
   static cpp_vtable handle_vtable_;
+  static cpp_vtable builtin_vtables_[kNumPredefinedKinds];
 
   // The static values below are singletons shared between the different
   // isolates. They are all allocated in the non-GC'd Dart::vm_isolate_.
@@ -418,6 +419,7 @@
   static RawClass* unhandled_exception_class_;  // Class of UnhandledException.
   static RawClass* unwind_error_class_;  // Class of UnwindError.
 
+  friend void ClassTable::Register(const Class& cls);
   friend void RawObject::Validate(Isolate* isolate) const;
   friend class SnapshotReader;
 
@@ -4901,8 +4903,9 @@
     set_vtable(Smi::handle_vtable_);
     return;
   }
-#ifdef DEBUG
-  Heap* isolate_heap = Isolate::Current()->heap();
+#if defined(DEBUG)
+  Isolate* isolate = Isolate::Current();
+  Heap* isolate_heap = isolate->heap();
   Heap* vm_isolate_heap = Dart::vm_isolate()->heap();
   ASSERT(isolate_heap->Contains(reinterpret_cast<uword>(raw_->ptr())) ||
          vm_isolate_heap->Contains(reinterpret_cast<uword>(raw_->ptr())));
@@ -4910,9 +4913,18 @@
   if (raw_ == null_) {
     set_vtable(handle_vtable_);

[siva, 2012/06/07 17:32:25]

I am wondering if we should pull the "if (raw_ == null_)" case above just after
the Smi check and return.

The rest of the code would indent better without the need for the 'else'.

[Ivan Posva, 2012/06/07 20:00:56]

Done. https://chromiumcodereview.appspot.com/10541061

On 2012/06/07 17:32:25, asiva wrote:

   } else {
-    RawClass* raw_class =
-      Isolate::Current()->class_table()->At(raw_->GetClassId());
-    set_vtable(raw_class->ptr()->handle_vtable_);
+    intptr_t cid = raw_->GetClassId();
+    if (cid < kNumPredefinedKinds) {
+      ASSERT(builtin_vtables_[cid] ==
+             isolate->class_table()->At(cid)->ptr()->handle_vtable_);
+      set_vtable(builtin_vtables_[cid]);
+    } else {
+#if !defined(DEBUG)
+      Isolate* isolate = Isolate::Current();
+#endif
+      RawClass* raw_class = isolate->class_table()->At(cid);
+      set_vtable(raw_class->ptr()->handle_vtable_);
+    }
   }
 }