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
38bool always_do_update_barrier = false;
39
40BarrierSet* oopDesc::_bs = NULL;
41
42void 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
50void oopDesc::print_address_on(outputStream* st) const {
51  st->print("{" INTPTR_FORMAT "}", p2i(this));
52
53}
54
55void oopDesc::print()         { print_on(tty);         }
56
57void oopDesc::print_address() { print_address_on(tty); }
58
59char* oopDesc::print_string() {
60  stringStream st;
61  print_on(&st);
62  return st.as_string();
63}
64
65void oopDesc::print_value() {
66  print_value_on(tty);
67}
68
69char* 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
76void 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
89void oopDesc::verify_on(outputStream* st) {
90  if (this != NULL) {
91    klass()->oop_verify_on(this, st);
92  }
93}
94
95
96void oopDesc::verify() {
97  verify_on(tty);
98}
99
100intptr_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
110unsigned 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
125bool 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)) return false;
128  // obj is aligned and accessible in heap
129  if (Universe::heap()->is_in_reserved(obj->klass_or_null())) return false;
130
131  // Header verification: the mark is typically non-NULL. If we're
132  // at a safepoint, it must not be null.
133  // Outside of a safepoint, the header could be changing (for example,
134  // another thread could be inflating a lock on this object).
135  if (ignore_mark_word) {
136    return true;
137  }
138  if (obj->mark() != NULL) {
139    return true;
140  }
141  return !SafepointSynchronize::is_at_safepoint();
142}
143
144// used only for asserts and guarantees
145bool oopDesc::is_oop_or_null(oop obj, bool ignore_mark_word) {
146  return obj == NULL ? true : is_oop(obj, ignore_mark_word);
147}
148
149#ifndef PRODUCT
150// used only for asserts
151bool oopDesc::is_unlocked_oop() const {
152  if (!Universe::heap()->is_in_reserved(this)) return false;
153  return mark()->is_unlocked();
154}
155#endif // PRODUCT
156
157VerifyOopClosure VerifyOopClosure::verify_oop;
158
159template <class T> void VerifyOopClosure::do_oop_work(T* p) {
160  oop obj = oopDesc::load_decode_heap_oop(p);
161  guarantee(oopDesc::is_oop_or_null(obj), "invalid oop: " INTPTR_FORMAT, p2i((oopDesc*) obj));
162}
163
164void VerifyOopClosure::do_oop(oop* p)       { VerifyOopClosure::do_oop_work(p); }
165void VerifyOopClosure::do_oop(narrowOop* p) { VerifyOopClosure::do_oop_work(p); }
166
167// type test operations that doesn't require inclusion of oop.inline.hpp.
168bool oopDesc::is_instance_noinline()          const { return is_instance();            }
169bool oopDesc::is_array_noinline()             const { return is_array();               }
170bool oopDesc::is_objArray_noinline()          const { return is_objArray();            }
171bool oopDesc::is_typeArray_noinline()         const { return is_typeArray();           }
172
173bool oopDesc::has_klass_gap() {
174  // Only has a klass gap when compressed class pointers are used.
175  return UseCompressedClassPointers;
176}
177
178#if INCLUDE_CDS_JAVA_HEAP
179bool oopDesc::is_archive_object(oop p) {
180  return (p == NULL) ? false : G1ArchiveAllocator::is_archive_object(p);
181}
182#endif
183