1 /* 2 * Copyright (c) 1997, 2025, 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 "cds/cdsConfig.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/compressedKlass.inline.hpp" 34 #include "oops/compressedOops.inline.hpp" 35 #include "oops/oop.inline.hpp" 36 #include "oops/verifyOopClosure.hpp" 37 #include "runtime/handles.inline.hpp" 38 #include "runtime/javaThread.hpp" 39 #include "runtime/synchronizer.hpp" 40 #include "utilities/macros.hpp" 41 42 void oopDesc::print_on(outputStream* st) const { 43 if (*((juint*)this) == badHeapWordVal) { 44 st->print_cr("BAD WORD"); 45 } else { 46 klass()->oop_print_on(cast_to_oop(this), st); 47 } 48 } 49 50 void oopDesc::print_address_on(outputStream* st) const { 51 st->print("{" PTR_FORMAT "}", p2i(this)); 52 53 } 54 55 void oopDesc::print_name_on(outputStream* st) const { 56 if (*((juint*)this) == badHeapWordVal) { 57 st->print_cr("BAD WORD"); 58 } else { 59 st->print_cr("%s", klass()->external_name()); 60 } 61 } 62 63 void oopDesc::print() { print_on(tty); } 64 65 void oopDesc::print_address() { print_address_on(tty); } 66 67 char* oopDesc::print_string() { 68 stringStream st; 69 print_on(&st); 70 return st.as_string(); 71 } 72 73 void oopDesc::print_value() { 74 print_value_on(tty); 75 } 76 77 char* oopDesc::print_value_string() { 78 char buf[100]; 79 stringStream st(buf, sizeof(buf)); 80 print_value_on(&st); 81 return st.as_string(); 82 } 83 84 void oopDesc::print_value_on(outputStream* st) const { 85 oop obj = const_cast<oopDesc*>(this); 86 if (java_lang_String::is_instance(obj)) { 87 java_lang_String::print(obj, st); 88 print_address_on(st); 89 } else { 90 klass()->oop_print_value_on(obj, st); 91 } 92 } 93 94 95 void oopDesc::verify_on(outputStream* st, oopDesc* oop_desc) { 96 if (oop_desc != nullptr) { 97 oop_desc->klass()->oop_verify_on(oop_desc, st); 98 } 99 } 100 101 102 void oopDesc::verify(oopDesc* oop_desc) { 103 verify_on(tty, oop_desc); 104 } 105 106 intptr_t oopDesc::slow_identity_hash() { 107 // slow case; we have to acquire the micro lock in order to locate the header 108 Thread* current = Thread::current(); 109 return ObjectSynchronizer::FastHashCode(current, this); 110 } 111 112 // used only for asserts and guarantees 113 bool oopDesc::is_oop(oop obj, bool ignore_mark_word) { 114 if (!Universe::heap()->is_oop(obj)) { 115 return false; 116 } 117 118 // Header verification: the mark is typically non-zero. If we're 119 // at a safepoint, it must not be zero, except when using the new lightweight locking. 120 // Outside of a safepoint, the header could be changing (for example, 121 // another thread could be inflating a lock on this object). 122 if (ignore_mark_word) { 123 return true; 124 } 125 if (obj->mark().value() != 0) { 126 return true; 127 } 128 return LockingMode == LM_LIGHTWEIGHT || !SafepointSynchronize::is_at_safepoint(); 129 } 130 131 // used only for asserts and guarantees 132 bool oopDesc::is_oop_or_null(oop obj, bool ignore_mark_word) { 133 return obj == nullptr ? true : is_oop(obj, ignore_mark_word); 134 } 135 136 VerifyOopClosure VerifyOopClosure::verify_oop; 137 138 template <class T> void VerifyOopClosure::do_oop_work(T* p) { 139 oop obj = RawAccess<>::oop_load(p); 140 guarantee(oopDesc::is_oop_or_null(obj), "invalid oop: " PTR_FORMAT, p2i(obj)); 141 } 142 143 void VerifyOopClosure::do_oop(oop* p) { VerifyOopClosure::do_oop_work(p); } 144 void VerifyOopClosure::do_oop(narrowOop* p) { VerifyOopClosure::do_oop_work(p); } 145 146 // type test operations that doesn't require inclusion of oop.inline.hpp. 147 bool oopDesc::is_instance_noinline() const { return is_instance(); } 148 bool oopDesc::is_instanceRef_noinline() const { return is_instanceRef(); } 149 bool oopDesc::is_stackChunk_noinline() const { return is_stackChunk(); } 150 bool oopDesc::is_array_noinline() const { return is_array(); } 151 bool oopDesc::is_objArray_noinline() const { return is_objArray(); } 152 bool oopDesc::is_typeArray_noinline() const { return is_typeArray(); } 153 154 #if INCLUDE_CDS_JAVA_HEAP 155 void oopDesc::set_narrow_klass(narrowKlass nk) { 156 assert(CDSConfig::is_dumping_heap(), "Used by CDS only. Do not abuse!"); 157 assert(UseCompressedClassPointers, "must be"); 158 _metadata._compressed_klass = nk; 159 } 160 #endif 161 162 void* oopDesc::load_oop_raw(oop obj, int offset) { 163 uintptr_t addr = (uintptr_t)(void*)obj + (uint)offset; 164 if (UseCompressedOops) { 165 narrowOop narrow_oop = *(narrowOop*)addr; 166 if (CompressedOops::is_null(narrow_oop)) return nullptr; 167 return (void*)CompressedOops::decode_raw(narrow_oop); 168 } else { 169 return *(void**)addr; 170 } 171 } 172 173 oop oopDesc::obj_field_acquire(int offset) const { return HeapAccess<MO_ACQUIRE>::oop_load_at(as_oop(), offset); } 174 175 void oopDesc::obj_field_put_raw(int offset, oop value) { assert(!UseZGC, "ZGC must use store barriers"); 176 RawAccess<>::oop_store_at(as_oop(), offset, value); } 177 void oopDesc::release_obj_field_put(int offset, oop value) { HeapAccess<MO_RELEASE>::oop_store_at(as_oop(), offset, value); } 178 void oopDesc::obj_field_put_volatile(int offset, oop value) { HeapAccess<MO_SEQ_CST>::oop_store_at(as_oop(), offset, value); } 179 180 address oopDesc::address_field(int offset) const { return *field_addr<address>(offset); } 181 address oopDesc::address_field_acquire(int offset) const { return Atomic::load_acquire(field_addr<address>(offset)); } 182 183 void oopDesc::address_field_put(int offset, address value) { *field_addr<address>(offset) = value; } 184 void oopDesc::release_address_field_put(int offset, address value) { Atomic::release_store(field_addr<address>(offset), value); } 185 186 Metadata* oopDesc::metadata_field(int offset) const { return *field_addr<Metadata*>(offset); } 187 void oopDesc::metadata_field_put(int offset, Metadata* value) { *field_addr<Metadata*>(offset) = value; } 188 189 Metadata* oopDesc::metadata_field_acquire(int offset) const { return Atomic::load_acquire(field_addr<Metadata*>(offset)); } 190 void oopDesc::release_metadata_field_put(int offset, Metadata* value) { Atomic::release_store(field_addr<Metadata*>(offset), value); } 191 192 jbyte oopDesc::byte_field_acquire(int offset) const { return Atomic::load_acquire(field_addr<jbyte>(offset)); } 193 void oopDesc::release_byte_field_put(int offset, jbyte value) { Atomic::release_store(field_addr<jbyte>(offset), value); } 194 195 jchar oopDesc::char_field_acquire(int offset) const { return Atomic::load_acquire(field_addr<jchar>(offset)); } 196 void oopDesc::release_char_field_put(int offset, jchar value) { Atomic::release_store(field_addr<jchar>(offset), value); } 197 198 jboolean oopDesc::bool_field_acquire(int offset) const { return Atomic::load_acquire(field_addr<jboolean>(offset)); } 199 void oopDesc::release_bool_field_put(int offset, jboolean value) { Atomic::release_store(field_addr<jboolean>(offset), jboolean(value & 1)); } 200 201 jint oopDesc::int_field_acquire(int offset) const { return Atomic::load_acquire(field_addr<jint>(offset)); } 202 void oopDesc::release_int_field_put(int offset, jint value) { Atomic::release_store(field_addr<jint>(offset), value); } 203 204 jshort oopDesc::short_field_acquire(int offset) const { return Atomic::load_acquire(field_addr<jshort>(offset)); } 205 void oopDesc::release_short_field_put(int offset, jshort value) { Atomic::release_store(field_addr<jshort>(offset), value); } 206 207 jlong oopDesc::long_field_acquire(int offset) const { return Atomic::load_acquire(field_addr<jlong>(offset)); } 208 void oopDesc::release_long_field_put(int offset, jlong value) { Atomic::release_store(field_addr<jlong>(offset), value); } 209 210 jfloat oopDesc::float_field_acquire(int offset) const { return Atomic::load_acquire(field_addr<jfloat>(offset)); } 211 void oopDesc::release_float_field_put(int offset, jfloat value) { Atomic::release_store(field_addr<jfloat>(offset), value); } 212 213 jdouble oopDesc::double_field_acquire(int offset) const { return Atomic::load_acquire(field_addr<jdouble>(offset)); } 214 void oopDesc::release_double_field_put(int offset, jdouble value) { Atomic::release_store(field_addr<jdouble>(offset), value); }