Implemented a ContextSlotCache for compiled code.

src/contexts.cc

 // Copyright 2006-2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 131 matching lines @@
           case Variable::DYNAMIC_GLOBAL: UNREACHABLE(); break;
           case Variable::DYNAMIC_LOCAL: UNREACHABLE(); break;
           case Variable::TEMPORARY: UNREACHABLE(); break;
         }
         return context;
       }
 
       // check parameter locals in context
       int param_index = ScopeInfo<>::ParameterIndex(*code, *name);
       if (param_index >= 0) {
-        // slot found
+        // slot found.
         int index =
             ScopeInfo<>::ContextSlotIndex(*code,
                                           Heap::arguments_shadow_symbol(),
                                           NULL);
         ASSERT(index >= 0);  // arguments must exist and be in the heap context
         Handle<JSObject> arguments(JSObject::cast(context->get(index)));
         ASSERT(arguments->HasLocalProperty(Heap::length_symbol()));
         if (FLAG_trace_contexts) {
           PrintF("=> found parameter %d in arguments object\n", param_index);
         }
@@ skipping 81 matching lines @@
 
 
 bool Context::IsBootstrappingOrGlobalObject(Object* object) {
   // During bootstrapping we allow all objects to pass as global
   // objects. This is necessary to fix circular dependencies.
   return Bootstrapper::IsActive() || object->IsGlobalObject();
 }
 #endif
 
 } }  // namespace v8::internal