1 /*
2 * Copyright (c) 1997, 2018, 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/access.inline.hpp"
30 #include "oops/oop.inline.hpp"
31 #include "oops/verifyOopClosure.hpp"
32 #include "runtime/handles.inline.hpp"
33 #include "runtime/thread.inline.hpp"
34 #include "utilities/copy.hpp"
35
36 bool always_do_update_barrier = false;
37
print_on(outputStream * st) const38 void oopDesc::print_on(outputStream* st) const {
39 if (this == NULL) {
40 st->print_cr("NULL");
41 } else {
42 klass()->oop_print_on(oop(this), st);
43 }
44 }
45
print_address_on(outputStream * st) const46 void oopDesc::print_address_on(outputStream* st) const {
47 st->print("{" INTPTR_FORMAT "}", p2i(this));
48
49 }
50
print()51 void oopDesc::print() { print_on(tty); }
52
print_address()53 void oopDesc::print_address() { print_address_on(tty); }
54
print_string()55 char* oopDesc::print_string() {
56 stringStream st;
57 print_on(&st);
58 return st.as_string();
59 }
60
print_value()61 void oopDesc::print_value() {
62 print_value_on(tty);
63 }
64
print_value_string()65 char* oopDesc::print_value_string() {
66 char buf[100];
67 stringStream st(buf, sizeof(buf));
68 print_value_on(&st);
69 return st.as_string();
70 }
71
print_value_on(outputStream * st) const72 void oopDesc::print_value_on(outputStream* st) const {
73 oop obj = oop(this);
74 if (this == NULL) {
75 st->print("NULL");
76 } else if (java_lang_String::is_instance(obj)) {
77 java_lang_String::print(obj, st);
78 print_address_on(st);
79 } else {
80 klass()->oop_print_value_on(obj, st);
81 }
82 }
83
84
verify_on(outputStream * st)85 void oopDesc::verify_on(outputStream* st) {
86 if (this != NULL) {
87 klass()->oop_verify_on(this, st);
88 }
89 }
90
91
verify()92 void oopDesc::verify() {
93 verify_on(tty);
94 }
95
slow_identity_hash()96 intptr_t oopDesc::slow_identity_hash() {
97 // slow case; we have to acquire the micro lock in order to locate the header
98 Thread* THREAD = Thread::current();
99 ResetNoHandleMark rnm; // Might be called from LEAF/QUICK ENTRY
100 HandleMark hm(THREAD);
101 Handle object(THREAD, this);
102 return ObjectSynchronizer::identity_hash_value_for(object);
103 }
104
105 // When String table needs to rehash
new_hash(juint seed)106 unsigned int oopDesc::new_hash(juint seed) {
107 EXCEPTION_MARK;
108 ResourceMark rm;
109 int length;
110 jchar* chars = java_lang_String::as_unicode_string(this, length, THREAD);
111 if (chars != NULL) {
112 // Use alternate hashing algorithm on the string
113 return AltHashing::halfsiphash_32(seed, chars, length);
114 } else {
115 vm_exit_out_of_memory(length, OOM_MALLOC_ERROR, "unable to create Unicode strings for String table rehash");
116 return 0;
117 }
118 }
119
120 // used only for asserts and guarantees
is_oop(oop obj,bool ignore_mark_word)121 bool oopDesc::is_oop(oop obj, bool ignore_mark_word) {
122 if (!Universe::heap()->is_oop(obj)) {
123 return false;
124 }
125
126 // Header verification: the mark is typically non-NULL. If we're
127 // at a safepoint, it must not be null.
128 // Outside of a safepoint, the header could be changing (for example,
129 // another thread could be inflating a lock on this object).
130 if (ignore_mark_word) {
131 return true;
132 }
133 if (obj->mark_raw() != NULL) {
134 return true;
135 }
136 return !SafepointSynchronize::is_at_safepoint();
137 }
138
139 // used only for asserts and guarantees
is_oop_or_null(oop obj,bool ignore_mark_word)140 bool oopDesc::is_oop_or_null(oop obj, bool ignore_mark_word) {
141 return obj == NULL ? true : is_oop(obj, ignore_mark_word);
142 }
143
144 #ifndef PRODUCT
145 // used only for asserts
is_unlocked_oop() const146 bool oopDesc::is_unlocked_oop() const {
147 if (!Universe::heap()->is_in_reserved(this)) return false;
148 return mark()->is_unlocked();
149 }
150 #endif // PRODUCT
151
152 VerifyOopClosure VerifyOopClosure::verify_oop;
153
do_oop_work(T * p)154 template <class T> void VerifyOopClosure::do_oop_work(T* p) {
155 oop obj = RawAccess<>::oop_load(p);
156 guarantee(oopDesc::is_oop_or_null(obj), "invalid oop: " INTPTR_FORMAT, p2i((oopDesc*) obj));
157 }
158
do_oop(oop * p)159 void VerifyOopClosure::do_oop(oop* p) { VerifyOopClosure::do_oop_work(p); }
do_oop(narrowOop * p)160 void VerifyOopClosure::do_oop(narrowOop* p) { VerifyOopClosure::do_oop_work(p); }
161
162 // type test operations that doesn't require inclusion of oop.inline.hpp.
is_instance_noinline() const163 bool oopDesc::is_instance_noinline() const { return is_instance(); }
is_array_noinline() const164 bool oopDesc::is_array_noinline() const { return is_array(); }
is_objArray_noinline() const165 bool oopDesc::is_objArray_noinline() const { return is_objArray(); }
is_typeArray_noinline() const166 bool oopDesc::is_typeArray_noinline() const { return is_typeArray(); }
167
has_klass_gap()168 bool oopDesc::has_klass_gap() {
169 // Only has a klass gap when compressed class pointers are used.
170 return UseCompressedClassPointers;
171 }
172
decode_oop_raw(narrowOop narrow_oop)173 oop oopDesc::decode_oop_raw(narrowOop narrow_oop) {
174 return (oop)(void*)( (uintptr_t)Universe::narrow_oop_base() +
175 ((uintptr_t)narrow_oop << Universe::narrow_oop_shift()));
176 }
177
load_klass_raw(oop obj)178 void* oopDesc::load_klass_raw(oop obj) {
179 if (UseCompressedClassPointers) {
180 narrowKlass narrow_klass = *(obj->compressed_klass_addr());
181 if (narrow_klass == 0) return NULL;
182 return (void*)Klass::decode_klass_raw(narrow_klass);
183 } else {
184 return *(void**)(obj->klass_addr());
185 }
186 }
187
load_oop_raw(oop obj,int offset)188 void* oopDesc::load_oop_raw(oop obj, int offset) {
189 uintptr_t addr = (uintptr_t)(void*)obj + (uint)offset;
190 if (UseCompressedOops) {
191 narrowOop narrow_oop = *(narrowOop*)addr;
192 if (narrow_oop == 0) return NULL;
193 return (void*)decode_oop_raw(narrow_oop);
194 } else {
195 return *(void**)addr;
196 }
197 }
198
is_valid(oop obj)199 bool oopDesc::is_valid(oop obj) {
200 if (!is_object_aligned(obj)) return false;
201 if ((size_t)(oopDesc*)obj < os::min_page_size()) return false;
202
203 // We need at least the mark and the klass word in the committed region.
204 if (!os::is_readable_range(obj, (oopDesc*)obj + 1)) return false;
205 if (!Universe::heap()->is_in(obj)) return false;
206
207 Klass* k = (Klass*)load_klass_raw(obj);
208
209 if (!os::is_readable_range(k, k + 1)) return false;
210 return MetaspaceUtils::is_range_in_committed(k, k + 1);
211 }
212
oop_or_null(address addr)213 oop oopDesc::oop_or_null(address addr) {
214 if (is_valid(oop(addr))) {
215 // We were just given an oop directly.
216 return oop(addr);
217 }
218
219 // Try to find addr using block_start.
220 HeapWord* p = Universe::heap()->block_start(addr);
221 if (p != NULL && Universe::heap()->block_is_obj(p)) {
222 if (!is_valid(oop(p))) return NULL;
223 return oop(p);
224 }
225
226 // If we can't find it it just may mean that heap wasn't parsable.
227 return NULL;
228 }
229
obj_field_acquire(int offset) const230 oop oopDesc::obj_field_acquire(int offset) const { return HeapAccess<MO_ACQUIRE>::oop_load_at(as_oop(), offset); }
231
obj_field_put_raw(int offset,oop value)232 void oopDesc::obj_field_put_raw(int offset, oop value) { RawAccess<>::oop_store_at(as_oop(), offset, value); }
release_obj_field_put(int offset,oop value)233 void oopDesc::release_obj_field_put(int offset, oop value) { HeapAccess<MO_RELEASE>::oop_store_at(as_oop(), offset, value); }
obj_field_put_volatile(int offset,oop value)234 void oopDesc::obj_field_put_volatile(int offset, oop value) { HeapAccess<MO_SEQ_CST>::oop_store_at(as_oop(), offset, value); }
235
address_field(int offset) const236 address oopDesc::address_field(int offset) const { return HeapAccess<>::load_at(as_oop(), offset); }
address_field_acquire(int offset) const237 address oopDesc::address_field_acquire(int offset) const { return HeapAccess<MO_ACQUIRE>::load_at(as_oop(), offset); }
238
address_field_put(int offset,address value)239 void oopDesc::address_field_put(int offset, address value) { HeapAccess<>::store_at(as_oop(), offset, value); }
release_address_field_put(int offset,address value)240 void oopDesc::release_address_field_put(int offset, address value) { HeapAccess<MO_RELEASE>::store_at(as_oop(), offset, value); }
241
metadata_field(int offset) const242 Metadata* oopDesc::metadata_field(int offset) const { return HeapAccess<>::load_at(as_oop(), offset); }
metadata_field_put(int offset,Metadata * value)243 void oopDesc::metadata_field_put(int offset, Metadata* value) { HeapAccess<>::store_at(as_oop(), offset, value); }
244
metadata_field_acquire(int offset) const245 Metadata* oopDesc::metadata_field_acquire(int offset) const { return HeapAccess<MO_ACQUIRE>::load_at(as_oop(), offset); }
release_metadata_field_put(int offset,Metadata * value)246 void oopDesc::release_metadata_field_put(int offset, Metadata* value) { HeapAccess<MO_RELEASE>::store_at(as_oop(), offset, value); }
247
byte_field_acquire(int offset) const248 jbyte oopDesc::byte_field_acquire(int offset) const { return HeapAccess<MO_ACQUIRE>::load_at(as_oop(), offset); }
release_byte_field_put(int offset,jbyte value)249 void oopDesc::release_byte_field_put(int offset, jbyte value) { HeapAccess<MO_RELEASE>::store_at(as_oop(), offset, value); }
250
char_field_acquire(int offset) const251 jchar oopDesc::char_field_acquire(int offset) const { return HeapAccess<MO_ACQUIRE>::load_at(as_oop(), offset); }
release_char_field_put(int offset,jchar value)252 void oopDesc::release_char_field_put(int offset, jchar value) { HeapAccess<MO_RELEASE>::store_at(as_oop(), offset, value); }
253
bool_field_acquire(int offset) const254 jboolean oopDesc::bool_field_acquire(int offset) const { return HeapAccess<MO_ACQUIRE>::load_at(as_oop(), offset); }
release_bool_field_put(int offset,jboolean value)255 void oopDesc::release_bool_field_put(int offset, jboolean value) { HeapAccess<MO_RELEASE>::store_at(as_oop(), offset, jboolean(value & 1)); }
256
int_field_acquire(int offset) const257 jint oopDesc::int_field_acquire(int offset) const { return HeapAccess<MO_ACQUIRE>::load_at(as_oop(), offset); }
release_int_field_put(int offset,jint value)258 void oopDesc::release_int_field_put(int offset, jint value) { HeapAccess<MO_RELEASE>::store_at(as_oop(), offset, value); }
259
short_field_acquire(int offset) const260 jshort oopDesc::short_field_acquire(int offset) const { return HeapAccess<MO_ACQUIRE>::load_at(as_oop(), offset); }
release_short_field_put(int offset,jshort value)261 void oopDesc::release_short_field_put(int offset, jshort value) { HeapAccess<MO_RELEASE>::store_at(as_oop(), offset, value); }
262
long_field_acquire(int offset) const263 jlong oopDesc::long_field_acquire(int offset) const { return HeapAccess<MO_ACQUIRE>::load_at(as_oop(), offset); }
release_long_field_put(int offset,jlong value)264 void oopDesc::release_long_field_put(int offset, jlong value) { HeapAccess<MO_RELEASE>::store_at(as_oop(), offset, value); }
265
float_field_acquire(int offset) const266 jfloat oopDesc::float_field_acquire(int offset) const { return HeapAccess<MO_ACQUIRE>::load_at(as_oop(), offset); }
release_float_field_put(int offset,jfloat value)267 void oopDesc::release_float_field_put(int offset, jfloat value) { HeapAccess<MO_RELEASE>::store_at(as_oop(), offset, value); }
268
double_field_acquire(int offset) const269 jdouble oopDesc::double_field_acquire(int offset) const { return HeapAccess<MO_ACQUIRE>::load_at(as_oop(), offset); }
release_double_field_put(int offset,jdouble value)270 void oopDesc::release_double_field_put(int offset, jdouble value) { HeapAccess<MO_RELEASE>::store_at(as_oop(), offset, value); }
271