1 /*
2 * Copyright (c) 1997, 2025, Oracle and/or its affiliates. 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 #include "precompiled.hpp"
26 #include "oops/markWord.hpp"
27 #include "runtime/basicLock.inline.hpp"
28 #include "runtime/javaThread.hpp"
29 #include "runtime/objectMonitor.inline.hpp"
30 #include "utilities/ostream.hpp"
31
32 markWord markWord::displaced_mark_helper() const {
33 assert(has_displaced_mark_helper(), "check");
34 if (has_monitor()) {
35 // Has an inflated monitor. Must be checked before has_locker().
36 ObjectMonitor* monitor = this->monitor();
37 return monitor->header();
38 }
39 if (has_locker()) { // has a stack lock
40 BasicLock* locker = this->locker();
41 return locker->displaced_header();
42 }
43 // This should never happen:
44 fatal("bad header=" INTPTR_FORMAT, value());
45 return markWord(value());
46 }
47
48 void markWord::set_displaced_mark_helper(markWord m) const {
49 assert(has_displaced_mark_helper(), "check");
50 if (has_monitor()) {
51 // Has an inflated monitor. Must be checked before has_locker().
52 ObjectMonitor* monitor = this->monitor();
53 monitor->set_header(m);
54 return;
55 }
56 if (has_locker()) { // has a stack lock
57 BasicLock* locker = this->locker();
58 locker->set_displaced_header(m);
59 return;
60 }
61 // This should never happen:
62 fatal("bad header=" INTPTR_FORMAT, value());
63 }
64
65 void markWord::print_on(outputStream* st, bool print_monitor_info) const {
66 if (is_marked()) { // last bits = 11
67 st->print(" marked(" INTPTR_FORMAT ")", value());
68 } else if (has_monitor()) { // last bits = 10
69 // have to check has_monitor() before is_locked()
70 st->print(" monitor(" INTPTR_FORMAT ")=", value());
71 if (print_monitor_info && !UseObjectMonitorTable) {
72 ObjectMonitor* mon = monitor();
73 if (mon == nullptr) {
74 st->print("null (this should never be seen!)");
75 } else {
76 mon->print_on(st);
77 }
78 }
79 } else if (is_locked()) { // last bits != 01 => 00
80 // thin locked
81 st->print(" locked(" INTPTR_FORMAT ")", value());
82 } else {
83 st->print(" mark(");
84 if (is_unlocked()) { // last bits = 01
85 st->print("is_unlocked");
86 if (has_no_hash()) {
87 st->print(" no_hash");
88 } else {
89 st->print(" hash=" INTPTR_FORMAT, hash());
90 }
91 } else {
92 st->print("??");
93 }
94 st->print(" age=%d)", age());
95 }
96 }
97
98 markWord markWord::flat_array_prototype(LayoutKind lk) {
99 switch(lk) {
100 case ATOMIC_FLAT:
101 case NON_ATOMIC_FLAT:
102 return markWord(null_free_flat_array_pattern);
103 break;
104 case NULLABLE_ATOMIC_FLAT:
105 return markWord(nullable_flat_array_pattern);
106 break;
107 default:
108 ShouldNotReachHere();
109 }
110 }