--- old/src/share/vm/runtime/sharedRuntime.cpp	2015-10-08 22:16:04.247908021 +0200
+++ new/src/share/vm/runtime/sharedRuntime.cpp	2015-10-08 22:16:04.197909215 +0200
@@ -211,6 +211,11 @@
 
 #endif // INCLUDE_ALL_GCS
 
+// G1 write-barrier pre: executed before a pointer store.
+JRT_LEAF(void, SharedRuntime::shenandoah_clone_barrier(oopDesc* obj))
+  oopDesc::bs()->write_region(MemRegion((HeapWord*) obj, obj->size()));
+JRT_END
+
 
 JRT_LEAF(jlong, SharedRuntime::lmul(jlong y, jlong x))
   return x * y;
@@ -1795,6 +1800,7 @@
 
 // Handles the uncommon case in locking, i.e., contention or an inflated lock.
 JRT_BLOCK_ENTRY(void, SharedRuntime::complete_monitor_locking_C(oopDesc* _obj, BasicLock* lock, JavaThread* thread))
+  _obj = oopDesc::bs()->write_barrier(_obj);
   // Disable ObjectSynchronizer::quick_enter() in default config
   // until JDK-8077392 is resolved.
   if ((SyncFlags & 256) != 0 && !SafepointSynchronize::is_synchronizing()) {
@@ -1824,6 +1830,7 @@
 
 // Handles the uncommon cases of monitor unlocking in compiled code
 JRT_LEAF(void, SharedRuntime::complete_monitor_unlocking_C(oopDesc* _obj, BasicLock* lock, JavaThread * THREAD))
+  _obj = oopDesc::bs()->write_barrier(_obj);
    oop obj(_obj);
   assert(JavaThread::current() == THREAD, "invariant");
   // I'm not convinced we need the code contained by MIGHT_HAVE_PENDING anymore