1 /*
2 * Copyright (c) 1997, 2017, 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 "classfile/altHashing.hpp"
27 #include "classfile/javaClasses.inline.hpp"
28 #include "memory/resourceArea.hpp"
29 #include "oops/oop.inline.hpp"
30 #include "oops/verifyOopClosure.hpp"
31 #include "runtime/handles.inline.hpp"
32 #include "runtime/thread.inline.hpp"
33 #include "utilities/copy.hpp"
34 #if INCLUDE_ALL_GCS
35 #include "gc/g1/g1Allocator.inline.hpp"
36 #endif
37
38 bool always_do_update_barrier = false;
39
40 BarrierSet* oopDesc::_bs = NULL;
41
42 void oopDesc::print_on(outputStream* st) const {
43 if (this == NULL) {
44 st->print_cr("NULL");
45 } else {
46 klass()->oop_print_on(oop(this), st);
47 }
48 }
49
50 void oopDesc::print_address_on(outputStream* st) const {
51 st->print("{" INTPTR_FORMAT "}", p2i(this));
52
53 }
54
55 void oopDesc::print() { print_on(tty); }
56
57 void oopDesc::print_address() { print_address_on(tty); }
58
59 char* oopDesc::print_string() {
60 stringStream st;
61 print_on(&st);
62 return st.as_string();
63 }
64
65 void oopDesc::print_value() {
66 print_value_on(tty);
67 }
68
69 char* oopDesc::print_value_string() {
70 char buf[100];
71 stringStream st(buf, sizeof(buf));
72 print_value_on(&st);
73 return st.as_string();
74 }
75
76 void oopDesc::print_value_on(outputStream* st) const {
77 oop obj = oop(this);
78 if (this == NULL) {
79 st->print("NULL");
80 } else if (java_lang_String::is_instance(obj)) {
81 java_lang_String::print(obj, st);
82 print_address_on(st);
83 } else {
84 klass()->oop_print_value_on(obj, st);
85 }
86 }
87
88
89 void oopDesc::verify_on(outputStream* st) {
90 if (this != NULL) {
91 klass()->oop_verify_on(this, st);
92 }
93 }
94
95
96 void oopDesc::verify() {
97 verify_on(tty);
98 }
99
100 intptr_t oopDesc::slow_identity_hash() {
101 // slow case; we have to acquire the micro lock in order to locate the header
102 Thread* THREAD = Thread::current();
103 ResetNoHandleMark rnm; // Might be called from LEAF/QUICK ENTRY
104 HandleMark hm(THREAD);
105 Handle object(THREAD, this);
106 return ObjectSynchronizer::identity_hash_value_for(object);
107 }
108
109 // When String table needs to rehash
110 unsigned int oopDesc::new_hash(juint seed) {
111 EXCEPTION_MARK;
112 ResourceMark rm;
113 int length;
114 jchar* chars = java_lang_String::as_unicode_string(this, length, THREAD);
115 if (chars != NULL) {
116 // Use alternate hashing algorithm on the string
117 return AltHashing::murmur3_32(seed, chars, length);
118 } else {
119 vm_exit_out_of_memory(length, OOM_MALLOC_ERROR, "unable to create Unicode strings for String table rehash");
120 return 0;
121 }
122 }
123
124 // used only for asserts and guarantees
125 bool oopDesc::is_oop(oop obj, bool ignore_mark_word) {
126 if (!check_obj_alignment(obj)) return false;
127 if (!Universe::heap()->is_in_reserved(obj)) {
128 assert(obj->klass()->is_value(), "Only value type can be outside of the Java heap");
129 VTBufferChunk* chunk = VTBufferChunk::chunk(obj);
130 assert(chunk->is_valid(), "if not in the heap, should a buffered VT");
131 if (!VTBuffer::is_in_vt_buffer(obj)) return false;
132 }
133 // obj is aligned and accessible in heap
134 if (Universe::heap()->is_in_reserved(obj->klass_or_null())) return false;
135
136 // Header verification: the mark is typically non-NULL. If we're
137 // at a safepoint, it must not be null.
138 // Outside of a safepoint, the header could be changing (for example,
139 // another thread could be inflating a lock on this object).
140 if (ignore_mark_word) {
141 return true;
142 }
143 if (obj->mark() != NULL) {
144 return true;
145 }
146 return !SafepointSynchronize::is_at_safepoint()
147 || (obj->klass()->is_value() && VTBuffer::is_in_vt_buffer(obj)) ;
148 }
149
150 // used only for asserts and guarantees
151 bool oopDesc::is_oop_or_null(oop obj, bool ignore_mark_word) {
152 return obj == NULL ? true : is_oop(obj, ignore_mark_word);
153 }
154
155 #ifndef PRODUCT
156 // used only for asserts
157 bool oopDesc::is_unlocked_oop() const {
158 if (!Universe::heap()->is_in_reserved(this)) return false;
159 return mark()->is_unlocked();
160 }
161 #endif // PRODUCT
162
163 VerifyOopClosure VerifyOopClosure::verify_oop;
164
165 template <class T> void VerifyOopClosure::do_oop_work(T* p) {
166 oop obj = oopDesc::load_decode_heap_oop(p);
167 guarantee(oopDesc::is_oop_or_null(obj), "invalid oop: " INTPTR_FORMAT, p2i((oopDesc*) obj));
168 }
169
170 void VerifyOopClosure::do_oop(oop* p) { VerifyOopClosure::do_oop_work(p); }
171 void VerifyOopClosure::do_oop(narrowOop* p) { VerifyOopClosure::do_oop_work(p); }
172
173 // type test operations that doesn't require inclusion of oop.inline.hpp.
174 bool oopDesc::is_instance_noinline() const { return is_instance(); }
175 bool oopDesc::is_array_noinline() const { return is_array(); }
176 bool oopDesc::is_objArray_noinline() const { return is_objArray(); }
177 bool oopDesc::is_typeArray_noinline() const { return is_typeArray(); }
178 bool oopDesc::is_value_noinline() const { return is_value(); }
179 bool oopDesc::is_valueArray_noinline() const { return is_valueArray(); }
180
181 bool oopDesc::has_klass_gap() {
182 // Only has a klass gap when compressed class pointers are used.
183 return UseCompressedClassPointers;
184 }
185
186 #if INCLUDE_CDS_JAVA_HEAP
187 bool oopDesc::is_archive_object(oop p) {
188 return (p == NULL) ? false : G1ArchiveAllocator::is_archive_object(p);
189 }
190 #endif