1 /* 2 * Copyright (c) 2015, 2019, Red Hat, Inc. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #ifndef SHARE_GC_SHENANDOAH_SHENANDOAHFORWARDING_INLINE_HPP 26 #define SHARE_GC_SHENANDOAH_SHENANDOAHFORWARDING_INLINE_HPP 27 28 #include "gc/shenandoah/shenandoahAsserts.hpp" 29 #include "gc/shenandoah/shenandoahForwarding.hpp" 30 #include "oops/markWord.inline.hpp" 31 32 inline HeapWord* ShenandoahForwarding::get_forwardee_raw(oop obj) { 33 shenandoah_assert_in_heap(NULL, obj); 34 return get_forwardee_raw_unchecked(obj); 35 } 36 37 inline HeapWord* ShenandoahForwarding::get_forwardee_raw_unchecked(oop obj) { 38 markWord mark = obj->mark_raw(); 39 if (mark.is_marked()) { 40 return (HeapWord*) mark.clear_lock_bits().to_pointer(); 41 } else { 42 return cast_from_oop<HeapWord*>(obj); 43 } 44 } 45 46 inline oop ShenandoahForwarding::get_forwardee(oop obj) { 47 shenandoah_assert_correct(NULL, obj); 48 return oop(get_forwardee_raw_unchecked(obj)); 49 } 50 51 inline bool ShenandoahForwarding::is_forwarded(oop obj) { 52 return obj->mark_raw().is_marked(); 53 } 54 55 inline oop ShenandoahForwarding::try_update_forwardee(oop obj, oop update) { 56 markWord old_mark = obj->mark_raw(); 57 if (old_mark.is_marked()) { 58 return oop(old_mark.clear_lock_bits().to_pointer()); 59 } 60 61 markWord new_mark = markWord::encode_pointer_as_mark(update); 62 markWord prev_mark = obj->cas_set_mark_raw(new_mark, old_mark); 63 if (prev_mark == old_mark) { 64 return update; 65 } else { 66 return oop(prev_mark.clear_lock_bits().to_pointer()); 67 } 68 } 69 70 #endif // SHARE_GC_SHENANDOAH_SHENANDOAHFORWARDING_INLINE_HPP