--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/gc/shared/c2/modRefBarrierSetC2.cpp	Fri May 18 14:51:06 2018 +0200
@@ -0,0 +1,135 @@
+/*
+ * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * 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 "opto/arraycopynode.hpp"
+#include "opto/graphKit.hpp"
+#include "opto/idealKit.hpp"
+#include "opto/narrowptrnode.hpp"
+#include "gc/shared/c2/modRefBarrierSetC2.hpp"
+#include "utilities/macros.hpp"
+
+Node* ModRefBarrierSetC2::store_at_resolved(C2Access& access, C2AccessValue& val) const {
+  DecoratorSet decorators = access.decorators();
+  GraphKit* kit = access.kit();
+
+  const TypePtr* adr_type = access.addr().type();
+  Node* adr = access.addr().node();
+
+  bool on_array = (decorators & IN_HEAP_ARRAY) != 0;
+  bool anonymous = (decorators & ON_UNKNOWN_OOP_REF) != 0;
+  bool on_heap = (decorators & IN_HEAP) != 0;
+  bool use_precise = on_array || anonymous;
+
+  if (!access.is_oop() || (!on_heap && !anonymous)) {
+    return BarrierSetC2::store_at_resolved(access, val);
+  }
+
+  uint adr_idx = kit->C->get_alias_index(adr_type);
+  assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
+
+  pre_barrier(kit, true /* do_load */, kit->control(), access.base(), adr, adr_idx, val.node(),
+              static_cast<const TypeOopPtr*>(val.type()), NULL /* pre_val */, access.type());
+  Node* store = BarrierSetC2::store_at_resolved(access, val);
+  post_barrier(kit, kit->control(), access.raw_access(), access.base(), adr, adr_idx, val.node(),
+               access.type(), use_precise);
+
+  return store;
+}
+
+Node* ModRefBarrierSetC2::atomic_cmpxchg_val_at_resolved(C2AtomicAccess& access, Node* expected_val,
+                                                         Node* new_val, const Type* value_type) const {
+  GraphKit* kit = access.kit();
+
+  if (!access.is_oop()) {
+    return BarrierSetC2::atomic_cmpxchg_val_at_resolved(access, expected_val, new_val, value_type);
+  }
+
+  pre_barrier(kit, false /* do_load */,
+              kit->control(), NULL, NULL, max_juint, NULL, NULL,
+              expected_val /* pre_val */, T_OBJECT);
+
+  Node* result = BarrierSetC2::atomic_cmpxchg_val_at_resolved(access, expected_val, new_val, value_type);
+
+  post_barrier(kit, kit->control(), access.raw_access(), access.base(),
+               access.addr().node(), access.alias_idx(), new_val, T_OBJECT, true);
+
+  return result;
+}
+
+Node* ModRefBarrierSetC2::atomic_cmpxchg_bool_at_resolved(C2AtomicAccess& access, Node* expected_val,
+                                                          Node* new_val, const Type* value_type) const {
+  GraphKit* kit = access.kit();
+
+  if (!access.is_oop()) {
+    return BarrierSetC2::atomic_cmpxchg_bool_at_resolved(access, expected_val, new_val, value_type);
+  }
+
+  pre_barrier(kit, false /* do_load */,
+              kit->control(), NULL, NULL, max_juint, NULL, NULL,
+              expected_val /* pre_val */, T_OBJECT);
+
+  Node* load_store = BarrierSetC2::atomic_cmpxchg_bool_at_resolved(access, expected_val, new_val, value_type);
+
+  // Emit the post barrier only when the actual store happened. This makes sense
+  // to check only for LS_cmp_* that can fail to set the value.
+  // LS_cmp_exchange does not produce any branches by default, so there is no
+  // boolean result to piggyback on. TODO: When we merge CompareAndSwap with
+  // CompareAndExchange and move branches here, it would make sense to conditionalize
+  // post_barriers for LS_cmp_exchange as well.
+  //
+  // CAS success path is marked more likely since we anticipate this is a performance
+  // critical path, while CAS failure path can use the penalty for going through unlikely
+  // path as backoff. Which is still better than doing a store barrier there.
+  IdealKit ideal(kit);
+  ideal.if_then(load_store, BoolTest::ne, ideal.ConI(0), PROB_STATIC_FREQUENT); {
+    kit->sync_kit(ideal);
+    post_barrier(kit, ideal.ctrl(), access.raw_access(), access.base(),
+                 access.addr().node(), access.alias_idx(), new_val, T_OBJECT, true);
+    ideal.sync_kit(kit);
+  } ideal.end_if();
+  kit->final_sync(ideal);
+
+  return load_store;
+}
+
+Node* ModRefBarrierSetC2::atomic_xchg_at_resolved(C2AtomicAccess& access, Node* new_val, const Type* value_type) const {
+  GraphKit* kit = access.kit();
+
+  Node* result = BarrierSetC2::atomic_xchg_at_resolved(access, new_val, value_type);
+  if (!access.is_oop()) {
+    return result;
+  }
+
+  // Don't need to load pre_val. The old value is returned by load_store.
+  // The pre_barrier can execute after the xchg as long as no safepoint
+  // gets inserted between them.
+  pre_barrier(kit, false /* do_load */,
+              kit->control(), NULL, NULL, max_juint, NULL, NULL,
+              result /* pre_val */, T_OBJECT);
+  post_barrier(kit, kit->control(), access.raw_access(), access.base(), access.addr().node(),
+               access.alias_idx(), new_val, T_OBJECT, true);
+
+  return result;
+}