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 "cds/cdsConfig.hpp"
26 #include "classfile/altHashing.hpp"
27 #include "classfile/javaClasses.inline.hpp"
28 #include "gc/shared/collectedHeap.inline.hpp"
29 #include "gc/shared/gc_globals.hpp"
30 #include "memory/resourceArea.hpp"
31 #include "memory/universe.hpp"
32 #include "oops/access.inline.hpp"
33 #include "oops/compressedKlass.inline.hpp"
34 #include "oops/compressedOops.inline.hpp"
35 #include "oops/oop.inline.hpp"
36 #include "oops/verifyOopClosure.hpp"
37 #include "runtime/handles.inline.hpp"
38 #include "runtime/javaThread.hpp"
39 #include "runtime/synchronizer.hpp"
40 #include "utilities/macros.hpp"
41
42 void oopDesc::print_on(outputStream* st) const {
43 if (*((juint*)this) == badHeapWordVal) {
44 st->print_cr("BAD WORD");
45 } else {
46 klass()->oop_print_on(cast_to_oop(this), st);
47 }
48 }
49
50 void oopDesc::print_address_on(outputStream* st) const {
51 st->print("{" PTR_FORMAT "}", p2i(this));
52
53 }
54
55 void oopDesc::print_name_on(outputStream* st) const {
56 if (*((juint*)this) == badHeapWordVal) {
57 st->print_cr("BAD WORD");
58 } else {
59 st->print_cr("%s", klass()->external_name());
60 }
61 }
62
63 void oopDesc::print() { print_on(tty); }
64
65 void oopDesc::print_address() { print_address_on(tty); }
66
67 char* oopDesc::print_string() {
68 stringStream st;
69 print_on(&st);
70 return st.as_string();
71 }
72
73 void oopDesc::print_value() {
74 print_value_on(tty);
75 }
76
77 char* oopDesc::print_value_string() {
78 char buf[100];
79 stringStream st(buf, sizeof(buf));
80 print_value_on(&st);
81 return st.as_string();
82 }
83
84 void oopDesc::print_value_on(outputStream* st) const {
85 oop obj = const_cast<oopDesc*>(this);
86 if (java_lang_String::is_instance(obj)) {
87 java_lang_String::print(obj, st);
88 print_address_on(st);
89 } else {
90 klass()->oop_print_value_on(obj, st);
91 }
92 }
93
94
95 void oopDesc::verify_on(outputStream* st, oopDesc* oop_desc) {
96 if (oop_desc != nullptr) {
97 oop_desc->klass()->oop_verify_on(oop_desc, st);
98 }
99 }
100
101
102 void oopDesc::verify(oopDesc* oop_desc) {
103 verify_on(tty, oop_desc);
104 }
105
106 intptr_t oopDesc::slow_identity_hash() {
107 // slow case; we have to acquire the micro lock in order to locate the header
108 Thread* current = Thread::current();
109 return ObjectSynchronizer::FastHashCode(current, this);
110 }
111
112 // used only for asserts and guarantees
113 bool oopDesc::is_oop(oop obj, bool ignore_mark_word) {
114 if (!Universe::heap()->is_oop(obj)) {
115 return false;
116 }
117
118 // Header verification: the mark is typically non-zero. If we're
119 // at a safepoint, it must not be zero, except when using the new lightweight locking.
120 // Outside of a safepoint, the header could be changing (for example,
121 // another thread could be inflating a lock on this object).
122 if (ignore_mark_word) {
123 return true;
124 }
125 if (obj->mark().value() != 0) {
126 return true;
127 }
128 return LockingMode == LM_LIGHTWEIGHT || !SafepointSynchronize::is_at_safepoint();
129 }
130
131 // used only for asserts and guarantees
132 bool oopDesc::is_oop_or_null(oop obj, bool ignore_mark_word) {
133 return obj == nullptr ? true : is_oop(obj, ignore_mark_word);
134 }
135
136 VerifyOopClosure VerifyOopClosure::verify_oop;
137
138 template <class T> void VerifyOopClosure::do_oop_work(T* p) {
139 oop obj = RawAccess<>::oop_load(p);
140 guarantee(oopDesc::is_oop_or_null(obj), "invalid oop: " PTR_FORMAT, p2i(obj));
141 }
142
143 void VerifyOopClosure::do_oop(oop* p) { VerifyOopClosure::do_oop_work(p); }
144 void VerifyOopClosure::do_oop(narrowOop* p) { VerifyOopClosure::do_oop_work(p); }
145
146 // type test operations that doesn't require inclusion of oop.inline.hpp.
147 bool oopDesc::is_instance_noinline() const { return is_instance(); }
148 bool oopDesc::is_instanceRef_noinline() const { return is_instanceRef(); }
149 bool oopDesc::is_stackChunk_noinline() const { return is_stackChunk(); }
150 bool oopDesc::is_array_noinline() const { return is_array(); }
151 bool oopDesc::is_objArray_noinline() const { return is_objArray(); }
152 bool oopDesc::is_typeArray_noinline() const { return is_typeArray(); }
153 bool oopDesc::is_flatArray_noinline() const { return is_flatArray(); }
154 bool oopDesc::is_null_free_array_noinline() const { return is_null_free_array(); }
155
156 #if INCLUDE_CDS_JAVA_HEAP
157 void oopDesc::set_narrow_klass(narrowKlass nk) {
158 assert(CDSConfig::is_dumping_heap(), "Used by CDS only. Do not abuse!");
159 assert(UseCompressedClassPointers, "must be");
160 _metadata._compressed_klass = nk;
161 }
162 #endif
163
164 void* oopDesc::load_oop_raw(oop obj, int offset) {
165 uintptr_t addr = (uintptr_t)(void*)obj + (uint)offset;
166 if (UseCompressedOops) {
167 narrowOop narrow_oop = *(narrowOop*)addr;
168 if (CompressedOops::is_null(narrow_oop)) return nullptr;
169 return (void*)CompressedOops::decode_raw(narrow_oop);
170 } else {
171 return *(void**)addr;
172 }
173 }
174
175 oop oopDesc::obj_field_acquire(int offset) const { return HeapAccess<MO_ACQUIRE>::oop_load_at(as_oop(), offset); }
176
177 void oopDesc::obj_field_put_raw(int offset, oop value) { assert(!UseZGC, "ZGC must use store barriers");
178 RawAccess<>::oop_store_at(as_oop(), offset, value); }
179 void oopDesc::release_obj_field_put(int offset, oop value) { HeapAccess<MO_RELEASE>::oop_store_at(as_oop(), offset, value); }
180 void oopDesc::obj_field_put_volatile(int offset, oop value) { HeapAccess<MO_SEQ_CST>::oop_store_at(as_oop(), offset, value); }
181
182 address oopDesc::address_field(int offset) const { return *field_addr<address>(offset); }
183 address oopDesc::address_field_acquire(int offset) const { return Atomic::load_acquire(field_addr<address>(offset)); }
184
185 void oopDesc::address_field_put(int offset, address value) { *field_addr<address>(offset) = value; }
186 void oopDesc::release_address_field_put(int offset, address value) { Atomic::release_store(field_addr<address>(offset), value); }
187
188 Metadata* oopDesc::metadata_field(int offset) const { return *field_addr<Metadata*>(offset); }
189 void oopDesc::metadata_field_put(int offset, Metadata* value) { *field_addr<Metadata*>(offset) = value; }
190
191 Metadata* oopDesc::metadata_field_acquire(int offset) const { return Atomic::load_acquire(field_addr<Metadata*>(offset)); }
192 void oopDesc::release_metadata_field_put(int offset, Metadata* value) { Atomic::release_store(field_addr<Metadata*>(offset), value); }
193
194 jbyte oopDesc::byte_field_acquire(int offset) const { return Atomic::load_acquire(field_addr<jbyte>(offset)); }
195 void oopDesc::release_byte_field_put(int offset, jbyte value) { Atomic::release_store(field_addr<jbyte>(offset), value); }
196
197 jchar oopDesc::char_field_acquire(int offset) const { return Atomic::load_acquire(field_addr<jchar>(offset)); }
198 void oopDesc::release_char_field_put(int offset, jchar value) { Atomic::release_store(field_addr<jchar>(offset), value); }
199
200 jboolean oopDesc::bool_field_acquire(int offset) const { return Atomic::load_acquire(field_addr<jboolean>(offset)); }
201 void oopDesc::release_bool_field_put(int offset, jboolean value) { Atomic::release_store(field_addr<jboolean>(offset), jboolean(value & 1)); }
202
203 jint oopDesc::int_field_acquire(int offset) const { return Atomic::load_acquire(field_addr<jint>(offset)); }
204 void oopDesc::release_int_field_put(int offset, jint value) { Atomic::release_store(field_addr<jint>(offset), value); }
205
206 jshort oopDesc::short_field_acquire(int offset) const { return Atomic::load_acquire(field_addr<jshort>(offset)); }
207 void oopDesc::release_short_field_put(int offset, jshort value) { Atomic::release_store(field_addr<jshort>(offset), value); }
208
209 jlong oopDesc::long_field_acquire(int offset) const { return Atomic::load_acquire(field_addr<jlong>(offset)); }
210 void oopDesc::release_long_field_put(int offset, jlong value) { Atomic::release_store(field_addr<jlong>(offset), value); }
211
212 jfloat oopDesc::float_field_acquire(int offset) const { return Atomic::load_acquire(field_addr<jfloat>(offset)); }
213 void oopDesc::release_float_field_put(int offset, jfloat value) { Atomic::release_store(field_addr<jfloat>(offset), value); }
214
215 jdouble oopDesc::double_field_acquire(int offset) const { return Atomic::load_acquire(field_addr<jdouble>(offset)); }
216 void oopDesc::release_double_field_put(int offset, jdouble value) { Atomic::release_store(field_addr<jdouble>(offset), value); }