1 /* 2 * Copyright (c) 2014, 2015, Red Hat, Inc. and/or its affiliates. 3 * 4 * This code is free software; you can redistribute it and/or modify it 5 * under the terms of the GNU General Public License version 2 only, as 6 * published by the Free Software Foundation. 7 * 8 * This code is distributed in the hope that it will be useful, but WITHOUT 9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 11 * version 2 for more details (a copy is included in the LICENSE file that 12 * accompanied this code). 13 * 14 * You should have received a copy of the GNU General Public License version 15 * 2 along with this work; if not, write to the Free Software Foundation, 16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 17 * 18 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 19 * or visit www.oracle.com if you need additional information or have any 20 * questions. 21 * 22 */ 23 24 #include "gc/shenandoah/shenandoahRuntime.hpp" 25 #include "gc/shenandoah/shenandoahBarrierSet.hpp" 26 #include "runtime/interfaceSupport.hpp" 27 #include "oops/oop.inline.hpp" 28 29 JRT_LEAF(bool, ShenandoahRuntime::compare_and_swap_object(HeapWord* addr, oopDesc* newval, oopDesc* old)) 30 bool success; 31 oop expected; 32 do { 33 expected = old; 34 old = oopDesc::atomic_compare_exchange_oop(newval, addr, expected, true); 35 success = (old == expected); 36 } while ((! success) && ShenandoahBarrierSet::resolve_oop_static(old) == ShenandoahBarrierSet::resolve_oop_static(expected)); 37 38 return success; 39 JRT_END