This patch much improves our tracking of whether function is...

src/runtime.cc

 // Copyright 2006-2009 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 4300 matching lines @@
 
   Handle<JSFunction> function = args.at<JSFunction>(0);
 #ifdef DEBUG
   if (FLAG_trace_lazy) {
     PrintF("[lazy: ");
     function->shared()->name()->Print();
     PrintF("]\n");
   }
 #endif
 
-  // Compile the target function.
+  // Compile the target function.  Here we compile using CompileLazyInLoop in
+  // order to get the optimized version.  This helps code like delta-blue
+  // that calls performance-critical routines through constructors.  A
+  // constructor call doesn't use a CallIC, it uses a LoadIC followed by a
+  // direct call.  Since the in-loop tracking takes place through CallICs
+  // this means that things called through constructors are never known to
+  // be in loops.  We compile them as if they are in loops here just in case.
   ASSERT(!function->is_compiled());
-  if (!CompileLazy(function, KEEP_EXCEPTION)) {
+  if (!CompileLazyInLoop(function, KEEP_EXCEPTION)) {
     return Failure::Exception();
   }
 
   return function->code();
 }
 
 
 static Object* Runtime_GetCalledFunction(Arguments args) {
   HandleScope scope;
   ASSERT(args.length() == 0);
@@ skipping 2703 matching lines @@
   } else {
     // Handle last resort GC and make sure to allow future allocations
     // to grow the heap without causing GCs (if possible).
     Counters::gc_last_resort_from_js.Increment();
     Heap::CollectAllGarbage();
   }
 }
 
 
 } }  // namespace v8::internal