1 /* 2 * Copyright (c) 2011, 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 "cds/serializeClosure.hpp" 27 #include "classfile/javaClasses.inline.hpp" 28 #include "gc/shared/collectedHeap.inline.hpp" 29 #include "memory/iterator.inline.hpp" 30 #include "memory/oopFactory.hpp" 31 #include "memory/universe.hpp" 32 #include "oops/instanceKlass.hpp" 33 #include "oops/instanceMirrorKlass.hpp" 34 #include "oops/instanceOop.hpp" 35 #include "oops/oop.inline.hpp" 36 #include "oops/symbol.hpp" 37 #include "runtime/handles.inline.hpp" 38 #include "utilities/macros.hpp" 39 40 int InstanceMirrorKlass::_offset_of_static_fields = 0; 41 42 InstanceMirrorKlass::InstanceMirrorKlass() { 43 assert(CDSConfig::is_dumping_static_archive() || CDSConfig::is_using_archive(), "only for CDS"); 44 } 45 46 size_t InstanceMirrorKlass::instance_size(Klass* k) { 47 if (k != nullptr && k->is_instance_klass()) { 48 return align_object_size(size_helper() + InstanceKlass::cast(k)->static_field_size()); 49 } 50 return size_helper(); 51 } 52 53 instanceOop InstanceMirrorKlass::allocate_instance(Klass* k, bool extend, TRAPS) { 54 // Query before forming handle. 55 size_t base_size = instance_size(k); 56 size_t size = base_size; 57 if (extend && UseCompactObjectHeaders) { 58 size = align_object_size(size + 1); 59 } 60 assert(base_size > 0, "base object size must be non-zero: %zu", base_size); 61 62 // Since mirrors can be variable sized because of the static fields, store 63 // the size in the mirror itself. 64 instanceOop obj = (instanceOop)Universe::heap()->class_allocate(this, size, base_size, THREAD); 65 if (extend && UseCompactObjectHeaders) { 66 obj->set_mark(obj->mark().set_not_hashed_expanded()); 67 } 68 return obj; 69 } 70 71 size_t InstanceMirrorKlass::oop_size(oop obj, markWord mark) const { 72 return java_lang_Class::oop_size(obj); 73 } 74 75 int InstanceMirrorKlass::compute_static_oop_field_count(oop obj) { 76 Klass* k = java_lang_Class::as_Klass(obj); 77 if (k != nullptr && k->is_instance_klass()) { 78 return InstanceKlass::cast(k)->static_oop_field_count(); 79 } 80 return 0; 81 } 82 83 int InstanceMirrorKlass::hash_offset_in_bytes(oop obj) const { 84 assert(UseCompactObjectHeaders, "only with compact i-hash"); 85 // TODO: There may be gaps that we could use, e.g. in the fields of Class, 86 // between the fields of Class and the static fields or in or at the end of 87 // the static fields block. 88 // When implementing any change here, make sure that allocate_instance() 89 // and corresponding code in InstanceMirrorKlass.java are in sync. 90 return checked_cast<int>(obj->base_size_given_klass(obj->mark(), this) * BytesPerWord); 91 } 92 93 #if INCLUDE_CDS 94 void InstanceMirrorKlass::serialize_offsets(SerializeClosure* f) { 95 f->do_int(&_offset_of_static_fields); 96 } 97 #endif