--- /dev/null	2020-01-17 11:46:19.065201212 +0100
+++ new/src/hotspot/share/gc/shenandoah/shenandoahRuntime.cpp	2020-01-17 17:10:34.598129130 +0100
@@ -0,0 +1,79 @@
+/*
+ * Copyright (c) 2018, Red Hat, Inc. All rights reserved.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ *
+ */
+
+#include "precompiled.hpp"
+#include "gc/shenandoah/shenandoahBarrierSet.inline.hpp"
+#include "gc/shenandoah/shenandoahBarrierSetClone.inline.hpp"
+#include "gc/shenandoah/shenandoahRuntime.hpp"
+#include "gc/shenandoah/shenandoahThreadLocalData.hpp"
+#include "runtime/interfaceSupport.inline.hpp"
+#include "oops/oop.inline.hpp"
+#include "utilities/copy.hpp"
+
+void ShenandoahRuntime::write_ref_array_pre_oop_entry(oop* src, oop* dst, size_t length) {
+  ShenandoahBarrierSet *bs = ShenandoahBarrierSet::barrier_set();
+  bs->arraycopy_pre(src, dst, length);
+}
+
+void ShenandoahRuntime::write_ref_array_pre_narrow_oop_entry(narrowOop* src, narrowOop* dst, size_t length) {
+  ShenandoahBarrierSet *bs = ShenandoahBarrierSet::barrier_set();
+  bs->arraycopy_pre(src, dst, length);
+}
+
+void ShenandoahRuntime::write_ref_array_pre_duinit_oop_entry(oop* src, oop* dst, size_t length) {
+  ShenandoahBarrierSet *bs = ShenandoahBarrierSet::barrier_set();
+  bs->arraycopy_update(src, length);
+}
+
+void ShenandoahRuntime::write_ref_array_pre_duinit_narrow_oop_entry(narrowOop* src, narrowOop* dst, size_t length) {
+  ShenandoahBarrierSet *bs = ShenandoahBarrierSet::barrier_set();
+  bs->arraycopy_update(src, length);
+}
+
+// Shenandoah pre write barrier slowpath
+JRT_LEAF(void, ShenandoahRuntime::write_ref_field_pre_entry(oopDesc* orig, JavaThread *thread))
+  if (orig == NULL) {
+    assert(false, "should be optimized out");
+    return;
+  }
+  shenandoah_assert_correct(NULL, orig);
+  // store the original value that was in the field reference
+  assert(ShenandoahThreadLocalData::satb_mark_queue(thread).is_active(), "Shouldn't be here otherwise");
+  ShenandoahThreadLocalData::satb_mark_queue(thread).enqueue_known_active(orig);
+JRT_END
+
+JRT_LEAF(oopDesc*, ShenandoahRuntime::load_reference_barrier(oopDesc* src, oop* load_addr))
+  return ShenandoahBarrierSet::barrier_set()->load_reference_barrier_mutator(src, load_addr);
+JRT_END
+
+JRT_LEAF(oopDesc*, ShenandoahRuntime::load_reference_barrier_narrow(oopDesc* src, narrowOop* load_addr))
+  return ShenandoahBarrierSet::barrier_set()->load_reference_barrier_mutator(src, load_addr);
+JRT_END
+
+// Shenandoah clone barrier: makes sure that references point to to-space
+// in cloned objects.
+JRT_LEAF(void, ShenandoahRuntime::shenandoah_clone_barrier(oopDesc* src))
+  oop s = oop(src);
+  shenandoah_assert_correct(NULL, s);
+  ShenandoahBarrierSet::barrier_set()->clone_barrier(s);
+JRT_END