*** old/src/share/vm/code/codeCache.cpp	Tue Jan 14 16:45:09 2014
--- new/src/share/vm/code/codeCache.cpp	Tue Jan 14 16:45:09 2014

*** 594,650 ****
--- 594,634 ----
      nm->clear_inline_caches();
    }
  }
  
  #ifndef PRODUCT
  // used to keep track of how much time is spent in mark_for_deoptimization
+ // Keeps track of time spent for checking dependencies
  static elapsedTimer dependentCheckTime;
  static int dependentCheckCount = 0;
  #endif // PRODUCT
+ #endif
  
  
  int CodeCache::mark_for_deoptimization(DepChange& changes) {
    MutexLockerEx mu(CodeCache_lock, Mutex::_no_safepoint_check_flag);
  
  #ifndef PRODUCT
    dependentCheckTime.start();
    dependentCheckCount++;
  #endif // PRODUCT
  
    int number_of_marked_CodeBlobs = 0;
  
    // search the hierarchy looking for nmethods which are affected by the loading of this class
  
    // then search the interfaces this class implements looking for nmethods
    // which might be dependent of the fact that an interface only had one
    // implementor.
  
    { No_Safepoint_Verifier nsv;
+   // nmethod::check_all_dependencies works only correctly, if no safepoint
+   // can happen
+   No_Safepoint_Verifier nsv;
    for (DepChange::ContextStream str(changes, nsv); str.next(); ) {
      Klass* d = str.klass();
      number_of_marked_CodeBlobs += InstanceKlass::cast(d)->mark_dependent_nmethods(changes);
    }
    }
  
    if (VerifyDependencies) {
      // Turn off dependency tracing while actually testing deps.
      NOT_PRODUCT( FlagSetting fs(TraceDependencies, false) );
      FOR_ALL_ALIVE_NMETHODS(nm) {
        if (!nm->is_marked_for_deoptimization() &&
            nm->check_all_dependencies()) {
          ResourceMark rm;
          tty->print_cr("Should have been marked for deoptimization:");
          changes.print();
          nm->print();
          nm->print_dependencies();
        }
      }
    }
  
  #ifndef PRODUCT
+   if (VerifyDependencies) {
+     // Object pointers are used as unique identifiers for dependency arguments. This
+     // is only possible if no safepoint, i.e., GC occurs during the verification code.
+     dependentCheckTime.start();
+     nmethod::check_all_dependencies(changes);
      dependentCheckTime.stop();
  #endif // PRODUCT
+   }
+ #endif
  
    return number_of_marked_CodeBlobs;
  }
  
  

*** 897,909 ****
--- 881,891 ----
        live.add(p);
      }
    }
  
    tty->print_cr("CodeCache:");
  
    tty->print_cr("nmethod dependency checking time %f", dependentCheckTime.seconds(),
                  dependentCheckTime.seconds() / dependentCheckCount);
+   tty->print_cr("nmethod dependency checking time %fs", dependentCheckTime.seconds());
  
    if (!live.is_empty()) {
      live.print("live");
    }
    if (!dead.is_empty()) {