Improve function lookup speed by working with raw objects only.

runtime/vm/object.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/object.h"
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "vm/assembler.h"
 #include "vm/bigint_operations.h"
@@ skipping 2253 matching lines @@
 
 
 RawFunction* Class::LookupFunction(const String& name) const {
   Isolate* isolate = Isolate::Current();
   ASSERT(name.IsOneByteString());
   Array& funcs = Array::Handle(isolate, functions());
   if (funcs.IsNull()) {
     // This can occur, e.g., for Null classes.
     return Function::null();
   }
-  Function& function = Function::Handle(isolate, Function::null());
+  const intptr_t len = funcs.Length();
   if (name.IsSymbol()) {
     // Quick Symbol compare.
-    intptr_t len = funcs.Length();
+    NoGCScope no_gc;
     for (intptr_t i = 0; i < len; i++) {
-      function ^= funcs.At(i);
-      if (function.name() == name.raw()) {
-        return function.raw();
+      RawFunction* raw_func = reinterpret_cast<RawFunction*>(funcs.At(i));
+      if (raw_func->ptr()->name_ == name.raw()) {
+        return raw_func;
       }
     }
   } else {
+    Function& function = Function::Handle(isolate, Function::null());
     String& function_name = String::Handle(isolate, String::null());
-    intptr_t len = funcs.Length();
     for (intptr_t i = 0; i < len; i++) {
       function ^= funcs.At(i);
       function_name ^= function.name();
       if (function_name.Equals(name)) {
         return function.raw();
       }
     }
   }
   // No function found.
   return Function::null();
@@ skipping 10298 matching lines @@
   }
   return result.raw();
 }
 
 
 const char* WeakProperty::ToCString() const {
   return "_WeakProperty";
 }
 
 }  // namespace dart