1 /*
  2  * Copyright (c) 1997, 2021, 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 "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/compressedOops.inline.hpp"
 34 #include "oops/oop.inline.hpp"
 35 #include "oops/verifyOopClosure.hpp"
 36 #include "runtime/handles.inline.hpp"
 37 #include "runtime/thread.inline.hpp"
 38 #include "utilities/copy.hpp"
 39 #include "utilities/macros.hpp"
 40 
 41 void oopDesc::print_on(outputStream* st) const {
 42   klass()->oop_print_on(const_cast<oopDesc*>(this), st);
 43 }
 44 
 45 void oopDesc::print_address_on(outputStream* st) const {
 46   st->print("{" INTPTR_FORMAT "}", p2i(this));
 47 
 48 }
 49 
 50 void oopDesc::print()         { print_on(tty);         }
 51 
 52 void oopDesc::print_address() { print_address_on(tty); }
 53 
 54 char* oopDesc::print_string() {
 55   stringStream st;
 56   print_on(&st);
 57   return st.as_string();
 58 }
 59 
 60 void oopDesc::print_value() {
 61   print_value_on(tty);
 62 }
 63 
 64 char* oopDesc::print_value_string() {
 65   char buf[100];
 66   stringStream st(buf, sizeof(buf));
 67   print_value_on(&st);
 68   return st.as_string();
 69 }
 70 
 71 void oopDesc::print_value_on(outputStream* st) const {
 72   oop obj = const_cast<oopDesc*>(this);
 73   if (java_lang_String::is_instance(obj)) {
 74     java_lang_String::print(obj, st);
 75     print_address_on(st);
 76   } else {
 77     klass()->oop_print_value_on(obj, st);
 78   }
 79 }
 80 
 81 
 82 void oopDesc::verify_on(outputStream* st, oopDesc* oop_desc) {
 83   if (oop_desc != NULL) {
 84     oop_desc->klass()->oop_verify_on(oop_desc, st);
 85   }
 86 }
 87 
 88 
 89 void oopDesc::verify(oopDesc* oop_desc) {
 90   verify_on(tty, oop_desc);
 91 }
 92 
 93 intptr_t oopDesc::slow_identity_hash() {
 94   // slow case; we have to acquire the micro lock in order to locate the header
 95   Thread* current = Thread::current();
 96   ResetNoHandleMark rnm; // Might be called from LEAF/QUICK ENTRY
 97   HandleMark hm(current);
 98   Handle object(current, this);
 99   return ObjectSynchronizer::identity_hash_value_for(object);
100 }
101 
102 // used only for asserts and guarantees
103 bool oopDesc::is_oop(oop obj, bool ignore_mark_word) {
104   if (!Universe::heap()->is_oop(obj)) {
105     return false;
106   }
107 
108   // Header verification: the mark is typically non-zero. If we're
109   // at a safepoint, it must not be zero.
110   // Outside of a safepoint, the header could be changing (for example,
111   // another thread could be inflating a lock on this object).
112   if (ignore_mark_word) {
113     return true;
114   }
115   if (obj->mark().value() != 0) {
116     return true;
117   }
118   return !SafepointSynchronize::is_at_safepoint();
119 }
120 
121 // used only for asserts and guarantees
122 bool oopDesc::is_oop_or_null(oop obj, bool ignore_mark_word) {
123   return obj == NULL ? true : is_oop(obj, ignore_mark_word);
124 }
125 
126 VerifyOopClosure VerifyOopClosure::verify_oop;
127 
128 template <class T> void VerifyOopClosure::do_oop_work(T* p) {
129   oop obj = RawAccess<>::oop_load(p);
130   guarantee(oopDesc::is_oop_or_null(obj), "invalid oop: " INTPTR_FORMAT, p2i((oopDesc*) obj));
131 }
132 
133 void VerifyOopClosure::do_oop(oop* p)       { VerifyOopClosure::do_oop_work(p); }
134 void VerifyOopClosure::do_oop(narrowOop* p) { VerifyOopClosure::do_oop_work(p); }
135 
136 // type test operations that doesn't require inclusion of oop.inline.hpp.
137 bool oopDesc::is_instance_noinline()          const { return is_instance();            }
138 bool oopDesc::is_array_noinline()             const { return is_array();               }
139 bool oopDesc::is_objArray_noinline()          const { return is_objArray();            }
140 bool oopDesc::is_typeArray_noinline()         const { return is_typeArray();           }
141 
142 bool oopDesc::has_klass_gap() {
143   // Only has a klass gap when compressed class pointers are used.
144   return UseCompressedClassPointers;
145 }
146 
147 #if INCLUDE_CDS_JAVA_HEAP
148 void oopDesc::set_narrow_klass(narrowKlass nk) {
149   assert(DumpSharedSpaces, "Used by CDS only. Do not abuse!");
150   assert(UseCompressedClassPointers, "must be");
151   _metadata._compressed_klass = nk;
152 }
153 #endif
154 
155 void* oopDesc::load_klass_raw(oop obj) {
156   if (UseCompressedClassPointers) {
157     narrowKlass narrow_klass = obj->_metadata._compressed_klass;
158     if (narrow_klass == 0) return NULL;
159     return (void*)CompressedKlassPointers::decode_raw(narrow_klass);
160   } else {
161     return obj->_metadata._klass;
162   }
163 }
164 
165 void* oopDesc::load_oop_raw(oop obj, int offset) {
166   uintptr_t addr = (uintptr_t)(void*)obj + (uint)offset;
167   if (UseCompressedOops) {
168     narrowOop narrow_oop = *(narrowOop*)addr;
169     if (CompressedOops::is_null(narrow_oop)) return NULL;
170     return (void*)CompressedOops::decode_raw(narrow_oop);
171   } else {
172     return *(void**)addr;
173   }
174 }
175 
176 oop oopDesc::obj_field_acquire(int offset) const                      { return HeapAccess<MO_ACQUIRE>::oop_load_at(as_oop(), offset); }
177 
178 void oopDesc::obj_field_put_raw(int offset, oop value)                { 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 HeapAccess<>::load_at(as_oop(), offset); }
183 address oopDesc::address_field_acquire(int offset) const              { return HeapAccess<MO_ACQUIRE>::load_at(as_oop(), offset); }
184 
185 void oopDesc::address_field_put(int offset, address value)            { HeapAccess<>::store_at(as_oop(), offset, value); }
186 void oopDesc::release_address_field_put(int offset, address value)    { HeapAccess<MO_RELEASE>::store_at(as_oop(), offset, value); }
187 
188 Metadata* oopDesc::metadata_field(int offset) const                   { return HeapAccess<>::load_at(as_oop(), offset); }
189 void oopDesc::metadata_field_put(int offset, Metadata* value)         { HeapAccess<>::store_at(as_oop(), offset, value); }
190 
191 Metadata* oopDesc::metadata_field_acquire(int offset) const           { return HeapAccess<MO_ACQUIRE>::load_at(as_oop(), offset); }
192 void oopDesc::release_metadata_field_put(int offset, Metadata* value) { HeapAccess<MO_RELEASE>::store_at(as_oop(), offset, value); }
193 
194 jbyte oopDesc::byte_field_acquire(int offset) const                   { return HeapAccess<MO_ACQUIRE>::load_at(as_oop(), offset); }
195 void oopDesc::release_byte_field_put(int offset, jbyte value)         { HeapAccess<MO_RELEASE>::store_at(as_oop(), offset, value); }
196 
197 jchar oopDesc::char_field_acquire(int offset) const                   { return HeapAccess<MO_ACQUIRE>::load_at(as_oop(), offset); }
198 void oopDesc::release_char_field_put(int offset, jchar value)         { HeapAccess<MO_RELEASE>::store_at(as_oop(), offset, value); }
199 
200 jboolean oopDesc::bool_field_acquire(int offset) const                { return HeapAccess<MO_ACQUIRE>::load_at(as_oop(), offset); }
201 void oopDesc::release_bool_field_put(int offset, jboolean value)      { HeapAccess<MO_RELEASE>::store_at(as_oop(), offset, jboolean(value & 1)); }
202 
203 jint oopDesc::int_field_acquire(int offset) const                     { return HeapAccess<MO_ACQUIRE>::load_at(as_oop(), offset); }
204 void oopDesc::release_int_field_put(int offset, jint value)           { HeapAccess<MO_RELEASE>::store_at(as_oop(), offset, value); }
205 
206 jshort oopDesc::short_field_acquire(int offset) const                 { return HeapAccess<MO_ACQUIRE>::load_at(as_oop(), offset); }
207 void oopDesc::release_short_field_put(int offset, jshort value)       { HeapAccess<MO_RELEASE>::store_at(as_oop(), offset, value); }
208 
209 jlong oopDesc::long_field_acquire(int offset) const                   { return HeapAccess<MO_ACQUIRE>::load_at(as_oop(), offset); }
210 void oopDesc::release_long_field_put(int offset, jlong value)         { HeapAccess<MO_RELEASE>::store_at(as_oop(), offset, value); }
211 
212 jfloat oopDesc::float_field_acquire(int offset) const                 { return HeapAccess<MO_ACQUIRE>::load_at(as_oop(), offset); }
213 void oopDesc::release_float_field_put(int offset, jfloat value)       { HeapAccess<MO_RELEASE>::store_at(as_oop(), offset, value); }
214 
215 jdouble oopDesc::double_field_acquire(int offset) const               { return HeapAccess<MO_ACQUIRE>::load_at(as_oop(), offset); }
216 void oopDesc::release_double_field_put(int offset, jdouble value)     { HeapAccess<MO_RELEASE>::store_at(as_oop(), offset, value); }
217 
218 #ifdef ASSERT
219 void oopDesc::verify_forwardee(oop forwardee) {
220 #if INCLUDE_CDS_JAVA_HEAP
221   assert(!Universe::heap()->is_archived_object(forwardee) && !Universe::heap()->is_archived_object(this),
222          "forwarding archive object");
223 #endif
224 }
225 
226 bool oopDesc::get_UseParallelGC() { return UseParallelGC; }
227 bool oopDesc::get_UseG1GC()       { return UseG1GC;       }
228 #endif