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/interfaceSupport.inline.hpp"
 38 #include "runtime/thread.inline.hpp"
 39 #include "utilities/copy.hpp"
 40 #include "utilities/macros.hpp"
 41 
 42 void oopDesc::print_on(outputStream* st) const {
 43   klass()->oop_print_on(const_cast<oopDesc*>(this), st);
 44 }
 45 
 46 void oopDesc::print_address_on(outputStream* st) const {
 47   st->print("{" INTPTR_FORMAT "}", p2i(this));
 48 
 49 }
 50 
 51 void oopDesc::print()         { print_on(tty);         }
 52 
 53 void oopDesc::print_address() { print_address_on(tty); }
 54 
 55 char* oopDesc::print_string() {
 56   stringStream st;
 57   print_on(&st);
 58   return st.as_string();
 59 }
 60 
 61 void oopDesc::print_value() {
 62   print_value_on(tty);
 63 }
 64 
 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 
 72 void oopDesc::print_value_on(outputStream* st) const {
 73   oop obj = const_cast<oopDesc*>(this);
 74   if (java_lang_String::is_instance(obj)) {
 75     java_lang_String::print(obj, st);
 76     print_address_on(st);
 77   } else {
 78     klass()->oop_print_value_on(obj, st);
 79   }
 80 }
 81 
 82 
 83 void oopDesc::verify_on(outputStream* st, oopDesc* oop_desc) {
 84   if (oop_desc != NULL) {
 85     oop_desc->klass()->oop_verify_on(oop_desc, st);
 86   }
 87 }
 88 
 89 
 90 void oopDesc::verify(oopDesc* oop_desc) {
 91   verify_on(tty, oop_desc);
 92 }
 93 
 94 intptr_t oopDesc::slow_identity_hash() {
 95   // slow case; we have to acquire the micro lock in order to locate the header
 96   Thread* current = Thread::current();
 97   ResetNoHandleMark rnm; // Might be called from LEAF/QUICK ENTRY
 98   HandleMark hm(current);
 99   Handle object(current, this);
100   return ObjectSynchronizer::identity_hash_value_for(object);
101 }
102 
103 // used only for asserts and guarantees
104 bool oopDesc::is_oop(oop obj, bool ignore_mark_word) {
105   if (!Universe::heap()->is_oop(obj)) {
106     return false;
107   }
108 
109   // Header verification: the mark is typically non-zero. If we're
110   // at a safepoint, it must not be zero.
111   // Outside of a safepoint, the header could be changing (for example,
112   // another thread could be inflating a lock on this object).
113   if (ignore_mark_word) {
114     return true;
115   }
116   if (obj->mark().value() != 0) {
117     return true;
118   }
119   return !SafepointSynchronize::is_at_safepoint();
120 }
121 
122 // used only for asserts and guarantees
123 bool oopDesc::is_oop_or_null(oop obj, bool ignore_mark_word) {
124   return obj == NULL ? true : is_oop(obj, ignore_mark_word);
125 }
126 
127 VerifyOopClosure VerifyOopClosure::verify_oop;
128 
129 template <class T> void VerifyOopClosure::do_oop_work(T* p) {
130   oop obj = RawAccess<>::oop_load(p);
131   guarantee(oopDesc::is_oop_or_null(obj), "invalid oop: " INTPTR_FORMAT, p2i((oopDesc*) obj));
132 }
133 
134 void VerifyOopClosure::do_oop(oop* p)       { VerifyOopClosure::do_oop_work(p); }
135 void VerifyOopClosure::do_oop(narrowOop* p) { VerifyOopClosure::do_oop_work(p); }
136 
137 // type test operations that doesn't require inclusion of oop.inline.hpp.
138 bool oopDesc::is_instance_noinline()          const { return is_instance();            }
139 bool oopDesc::is_array_noinline()             const { return is_array();               }
140 bool oopDesc::is_objArray_noinline()          const { return is_objArray();            }
141 bool oopDesc::is_typeArray_noinline()         const { return is_typeArray();           }
142 
143 bool oopDesc::has_klass_gap() {
144   // Only has a klass gap when compressed class pointers are used.
145   return UseCompressedClassPointers;
146 }
147 
148 #if INCLUDE_CDS_JAVA_HEAP
149 void oopDesc::set_narrow_klass(narrowKlass nk) {
150   assert(DumpSharedSpaces, "Used by CDS only. Do not abuse!");
151   assert(UseCompressedClassPointers, "must be");
152   _metadata._compressed_klass = nk;
153 }
154 #endif
155 
156 void* oopDesc::load_klass_raw(oop obj) {
157   if (UseCompressedClassPointers) {
158     narrowKlass narrow_klass = obj->_metadata._compressed_klass;
159     if (narrow_klass == 0) return NULL;
160     return (void*)CompressedKlassPointers::decode_raw(narrow_klass);
161   } else {
162     return obj->_metadata._klass;
163   }
164 }
165 
166 void* oopDesc::load_oop_raw(oop obj, int offset) {
167   uintptr_t addr = (uintptr_t)(void*)obj + (uint)offset;
168   if (UseCompressedOops) {
169     narrowOop narrow_oop = *(narrowOop*)addr;
170     if (CompressedOops::is_null(narrow_oop)) return NULL;
171     return (void*)CompressedOops::decode_raw(narrow_oop);
172   } else {
173     return *(void**)addr;
174   }
175 }
176 
177 JRT_LEAF(Klass*, oopDesc::load_klass_runtime(oopDesc* o))
178   assert(o != NULL, "null-check");
179   return oop(o)->klass();
180 JRT_END
181 
182 oop oopDesc::obj_field_acquire(int offset) const                      { return HeapAccess<MO_ACQUIRE>::oop_load_at(as_oop(), offset); }
183 
184 void oopDesc::obj_field_put_raw(int offset, oop value)                { RawAccess<>::oop_store_at(as_oop(), offset, value); }
185 void oopDesc::release_obj_field_put(int offset, oop value)            { HeapAccess<MO_RELEASE>::oop_store_at(as_oop(), offset, value); }
186 void oopDesc::obj_field_put_volatile(int offset, oop value)           { HeapAccess<MO_SEQ_CST>::oop_store_at(as_oop(), offset, value); }
187 
188 address oopDesc::address_field(int offset) const                      { return *field_addr<address>(offset); }
189 address oopDesc::address_field_acquire(int offset) const              { return Atomic::load_acquire(field_addr<address>(offset)); }
190 
191 void oopDesc::address_field_put(int offset, address value)            { *field_addr<address>(offset) = value; }
192 void oopDesc::release_address_field_put(int offset, address value)    { Atomic::release_store(field_addr<address>(offset), value); }
193 
194 Metadata* oopDesc::metadata_field(int offset) const                   { return *field_addr<Metadata*>(offset); }
195 void oopDesc::metadata_field_put(int offset, Metadata* value)         { *field_addr<Metadata*>(offset) = value; }
196 
197 Metadata* oopDesc::metadata_field_acquire(int offset) const           { return Atomic::load_acquire(field_addr<Metadata*>(offset)); }
198 void oopDesc::release_metadata_field_put(int offset, Metadata* value) { Atomic::release_store(field_addr<Metadata*>(offset), value); }
199 
200 jbyte oopDesc::byte_field_acquire(int offset) const                   { return Atomic::load_acquire(field_addr<jbyte>(offset)); }
201 void oopDesc::release_byte_field_put(int offset, jbyte value)         { Atomic::release_store(field_addr<jbyte>(offset), value); }
202 
203 jchar oopDesc::char_field_acquire(int offset) const                   { return Atomic::load_acquire(field_addr<jchar>(offset)); }
204 void oopDesc::release_char_field_put(int offset, jchar value)         { Atomic::release_store(field_addr<jchar>(offset), value); }
205 
206 jboolean oopDesc::bool_field_acquire(int offset) const                { return Atomic::load_acquire(field_addr<jboolean>(offset)); }
207 void oopDesc::release_bool_field_put(int offset, jboolean value)      { Atomic::release_store(field_addr<jboolean>(offset), jboolean(value & 1)); }
208 
209 jint oopDesc::int_field_acquire(int offset) const                     { return Atomic::load_acquire(field_addr<jint>(offset)); }
210 void oopDesc::release_int_field_put(int offset, jint value)           { Atomic::release_store(field_addr<jint>(offset), value); }
211 
212 jshort oopDesc::short_field_acquire(int offset) const                 { return Atomic::load_acquire(field_addr<jshort>(offset)); }
213 void oopDesc::release_short_field_put(int offset, jshort value)       { Atomic::release_store(field_addr<jshort>(offset), value); }
214 
215 jlong oopDesc::long_field_acquire(int offset) const                   { return Atomic::load_acquire(field_addr<jlong>(offset)); }
216 void oopDesc::release_long_field_put(int offset, jlong value)         { Atomic::release_store(field_addr<jlong>(offset), value); }
217 
218 jfloat oopDesc::float_field_acquire(int offset) const                 { return Atomic::load_acquire(field_addr<jfloat>(offset)); }
219 void oopDesc::release_float_field_put(int offset, jfloat value)       { Atomic::release_store(field_addr<jfloat>(offset), value); }
220 
221 jdouble oopDesc::double_field_acquire(int offset) const               { return Atomic::load_acquire(field_addr<jdouble>(offset)); }
222 void oopDesc::release_double_field_put(int offset, jdouble value)     { Atomic::release_store(field_addr<jdouble>(offset), value); }
223 
224 #ifdef ASSERT
225 void oopDesc::verify_forwardee(oop forwardee) {
226 #if INCLUDE_CDS_JAVA_HEAP
227   assert(!Universe::heap()->is_archived_object(forwardee) && !Universe::heap()->is_archived_object(this),
228          "forwarding archive object");
229 #endif
230 }
231 
232 bool oopDesc::get_UseParallelGC() { return UseParallelGC; }
233 bool oopDesc::get_UseG1GC()       { return UseG1GC;       }
234 #endif