Allocate fewer empty arrays.

runtime/vm/object.cc

Index: runtime/vm/object.cc
===================================================================
--- runtime/vm/object.cc	(revision 38066)
+++ runtime/vm/object.cc	(working copy)
@@ -6468,7 +6468,7 @@
     }
   }
 
-  const Array& a = Array::Handle(Array::New(count, Heap::kOld));
+  const Array& a = Array::Handle(Array::NewOrEmpty(count, Heap::kOld));
   count = 0;
   for (intptr_t i = 0; i < deopt_id_to_ic_data.length(); i++) {
     if (deopt_id_to_ic_data[i] != NULL) {
@@ -10593,7 +10593,8 @@
     result ^= raw;
     result.raw_ptr()->length_ = num_variables;
   }
-  const Array& names = Array::Handle(Array::New(num_variables, Heap::kOld));
+  const Array& names =
+      Array::Handle(Array::NewOrEmpty(num_variables, Heap::kOld));
   result.raw_ptr()->names_ = names.raw();

[siva, 2014/07/09 20:08:02]

ditto here too, avoids the handle creation.

   return result.raw();
 }
@@ -10694,7 +10695,8 @@
     result ^= raw;
     result.raw_ptr()->length_ = num_handlers;
   }
-  const Array& handled_types_data = Array::Handle(Array::New(num_handlers));
+  const Array& handled_types_data =
+      Array::Handle(Array::NewOrEmpty(num_handlers));

[siva, 2014/07/09 20:08:02]

Ditto.

   result.set_handled_types_data(handled_types_data);
   return result.raw();
 }