--- old/src/share/vm/runtime/synchronizer.cpp	2015-10-08 22:16:04.632898826 +0200
+++ new/src/share/vm/runtime/synchronizer.cpp	2015-10-08 22:16:04.581900044 +0200
@@ -160,6 +160,7 @@
   assert(!SafepointSynchronize::is_at_safepoint(), "invariant");
   assert(self->is_Java_thread(), "invariant");
   assert(((JavaThread *) self)->thread_state() == _thread_in_Java, "invariant");
+  assert(obj == oopDesc::bs()->write_barrier(obj), "expect to-space copy");
   No_Safepoint_Verifier nsv;
   if (obj == NULL) return false;  // slow-path for invalid obj
   const markOop mark = obj->mark();
@@ -210,6 +211,7 @@
   assert(!SafepointSynchronize::is_at_safepoint(), "invariant");
   assert(Self->is_Java_thread(), "invariant");
   assert(((JavaThread *) Self)->thread_state() == _thread_in_Java, "invariant");
+  assert(obj == oopDesc::bs()->write_barrier(obj), "expect to-space copy");
   No_Safepoint_Verifier nsv;
   if (obj == NULL) return false;       // Need to throw NPE
   const markOop mark = obj->mark();
@@ -256,6 +258,7 @@
 
 void ObjectSynchronizer::fast_enter(Handle obj, BasicLock* lock,
                                     bool attempt_rebias, TRAPS) {
+  assert(obj() == oopDesc::bs()->write_barrier(obj()), "expect to-space copy");
   if (UseBiasedLocking) {
     if (!SafepointSynchronize::is_at_safepoint()) {
       BiasedLocking::Condition cond = BiasedLocking::revoke_and_rebias(obj, attempt_rebias, THREAD);
@@ -275,6 +278,8 @@
 void ObjectSynchronizer::fast_exit(oop object, BasicLock* lock, TRAPS) {
   assert(!object->mark()->has_bias_pattern(), "should not see bias pattern here");
   // if displaced header is null, the previous enter is recursive enter, no-op
+  assert(object == oopDesc::bs()->write_barrier(object), "expect to-space copy");
+
   markOop dhw = lock->displaced_header();
   markOop mark;
   if (dhw == NULL) {
@@ -314,6 +319,7 @@
 // We don't need to use fast path here, because it must have been
 // failed in the interpreter/compiler code.
 void ObjectSynchronizer::slow_enter(Handle obj, BasicLock* lock, TRAPS) {
+  assert(obj() == oopDesc::bs()->write_barrier(obj()), "expect to-space copy");
   markOop mark = obj->mark();
   assert(!mark->has_bias_pattern(), "should not see bias pattern here");
 
@@ -364,6 +370,7 @@
 // NOTE: must use heavy weight monitor to handle complete_exit/reenter()
 intptr_t ObjectSynchronizer::complete_exit(Handle obj, TRAPS) {
   TEVENT(complete_exit);
+  assert(obj() == oopDesc::bs()->write_barrier(obj()), "expect to-space copy");
   if (UseBiasedLocking) {
     BiasedLocking::revoke_and_rebias(obj, false, THREAD);
     assert(!obj->mark()->has_bias_pattern(), "biases should be revoked by now");
@@ -377,6 +384,7 @@
 // NOTE: must use heavy weight monitor to handle complete_exit/reenter()
 void ObjectSynchronizer::reenter(Handle obj, intptr_t recursion, TRAPS) {
   TEVENT(reenter);
+  assert(obj() == oopDesc::bs()->write_barrier(obj()), "expect to-space copy");
   if (UseBiasedLocking) {
     BiasedLocking::revoke_and_rebias(obj, false, THREAD);
     assert(!obj->mark()->has_bias_pattern(), "biases should be revoked by now");
@@ -392,6 +400,7 @@
 void ObjectSynchronizer::jni_enter(Handle obj, TRAPS) {
   // the current locking is from JNI instead of Java code
   TEVENT(jni_enter);
+  assert(obj() == oopDesc::bs()->write_barrier(obj()), "expect to-space copy");
   if (UseBiasedLocking) {
     BiasedLocking::revoke_and_rebias(obj, false, THREAD);
     assert(!obj->mark()->has_bias_pattern(), "biases should be revoked by now");
@@ -404,6 +413,7 @@
 // NOTE: must use heavy weight monitor to handle jni monitor exit
 void ObjectSynchronizer::jni_exit(oop obj, Thread* THREAD) {
   TEVENT(jni_exit);
+  assert(obj == oopDesc::bs()->write_barrier(obj), "expect to-space copy");
   if (UseBiasedLocking) {
     Handle h_obj(THREAD, obj);
     BiasedLocking::revoke_and_rebias(h_obj, false, THREAD);
@@ -446,6 +456,7 @@
 //  Wait/Notify/NotifyAll
 // NOTE: must use heavy weight monitor to handle wait()
 int ObjectSynchronizer::wait(Handle obj, jlong millis, TRAPS) {
+  assert(obj() == oopDesc::bs()->write_barrier(obj()), "expect to-space copy");
   if (UseBiasedLocking) {
     BiasedLocking::revoke_and_rebias(obj, false, THREAD);
     assert(!obj->mark()->has_bias_pattern(), "biases should be revoked by now");
@@ -466,6 +477,7 @@
 }
 
 void ObjectSynchronizer::waitUninterruptibly(Handle obj, jlong millis, TRAPS) {
+  assert(obj() == oopDesc::bs()->write_barrier(obj()), "expect to-space copy");
   if (UseBiasedLocking) {
     BiasedLocking::revoke_and_rebias(obj, false, THREAD);
     assert(!obj->mark()->has_bias_pattern(), "biases should be revoked by now");
@@ -478,6 +490,7 @@
 }
 
 void ObjectSynchronizer::notify(Handle obj, TRAPS) {
+  assert(obj() == oopDesc::bs()->write_barrier(obj()), "expect to-space copy");
   if (UseBiasedLocking) {
     BiasedLocking::revoke_and_rebias(obj, false, THREAD);
     assert(!obj->mark()->has_bias_pattern(), "biases should be revoked by now");
@@ -492,6 +505,7 @@
 
 // NOTE: see comment of notify()
 void ObjectSynchronizer::notifyall(Handle obj, TRAPS) {
+  assert(obj() == oopDesc::bs()->write_barrier(obj()), "expect to-space copy");
   if (UseBiasedLocking) {
     BiasedLocking::revoke_and_rebias(obj, false, THREAD);
     assert(!obj->mark()->has_bias_pattern(), "biases should be revoked by now");
@@ -669,6 +683,7 @@
 }
 
 intptr_t ObjectSynchronizer::FastHashCode(Thread * Self, oop obj) {
+  assert(obj == oopDesc::bs()->write_barrier(obj), "expect to-space copy");
   if (UseBiasedLocking) {
     // NOTE: many places throughout the JVM do not expect a safepoint
     // to be taken here, in particular most operations on perm gen
@@ -782,6 +797,7 @@
 
 bool ObjectSynchronizer::current_thread_holds_lock(JavaThread* thread,
                                                    Handle h_obj) {
+  assert(h_obj() == oopDesc::bs()->write_barrier(h_obj()), "expect to-space copy");
   if (UseBiasedLocking) {
     BiasedLocking::revoke_and_rebias(h_obj, false, thread);
     assert(!h_obj->mark()->has_bias_pattern(), "biases should be revoked by now");
@@ -854,6 +870,7 @@
 
 // FIXME: jvmti should call this
 JavaThread* ObjectSynchronizer::get_lock_owner(Handle h_obj, bool doLock) {
+  assert(h_obj() == oopDesc::bs()->write_barrier(h_obj()), "expect to-space copy");
   if (UseBiasedLocking) {
     if (SafepointSynchronize::is_at_safepoint()) {
       BiasedLocking::revoke_at_safepoint(h_obj);
@@ -1275,6 +1292,7 @@
 
 // Fast path code shared by multiple functions
 ObjectMonitor* ObjectSynchronizer::inflate_helper(oop obj) {
+  assert(obj == oopDesc::bs()->write_barrier(obj), "expect to-space copy");
   markOop mark = obj->mark();
   if (mark->has_monitor()) {
     assert(ObjectSynchronizer::verify_objmon_isinpool(mark->monitor()), "monitor is invalid");
@@ -1289,6 +1307,7 @@
                                                      oop object) {
   // Inflate mutates the heap ...
   // Relaxing assertion for bug 6320749.
+  assert(object == oopDesc::bs()->write_barrier(object), "expect to-space copy");
   assert(Universe::verify_in_progress() ||
          !SafepointSynchronize::is_at_safepoint(), "invariant");
 
@@ -1307,7 +1326,7 @@
     if (mark->has_monitor()) {
       ObjectMonitor * inf = mark->monitor();
       assert(inf->header()->is_neutral(), "invariant");
-      assert(inf->object() == object, "invariant");
+      assert((oop) inf->object() == object, "invariant");
       assert(ObjectSynchronizer::verify_objmon_isinpool(inf), "monitor is invalid");
       return inf;
     }
@@ -1513,6 +1532,7 @@
                                          ObjectMonitor** freeTailp) {
   bool deflated;
   // Normal case ... The monitor is associated with obj.
+  assert(obj == oopDesc::bs()->write_barrier(obj), "expect to-space copy");
   guarantee(obj->mark() == markOopDesc::encode(mid), "invariant");
   guarantee(mid == obj->mark()->monitor(), "invariant");
   guarantee(mid->header()->is_neutral(), "invariant");
@@ -1798,6 +1818,7 @@
     for (int i = 1; i < _BLOCKSIZE; i++) {
       mid = (ObjectMonitor *)(block + i);
       oop object = (oop) mid->object();
+
       if (object != NULL) {
         mid->verify();
       }