1 /*
  2  * Copyright (c) 2023, 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/archiveBuilder.hpp"
 26 #include "cds/regeneratedClasses.hpp"
 27 #include "classfile/vmSymbols.hpp"
 28 #include "memory/universe.hpp"
 29 #include "oops/instanceKlass.hpp"
 30 #include "oops/method.hpp"
 31 #include "oops/oopHandle.inline.hpp"
 32 #include "runtime/mutexLocker.hpp"
 33 #include "runtime/thread.hpp"
 34 #include "utilities/growableArray.hpp"
 35 #include "utilities/hashTable.hpp"
 36 
 37 using RegeneratedObjTable = HashTable<address, address, 15889, AnyObj::C_HEAP, mtClassShared>;
 38 static RegeneratedObjTable* _regenerated_objs = nullptr; // InstanceKlass* and Method*  orig_obj  -> regen_obj
 39 static RegeneratedObjTable* _original_objs = nullptr;    // InstanceKlass* and Method*  regen_obj -> orig_obj
 40 static GrowableArrayCHeap<OopHandle, mtClassShared>* _regenerated_mirrors = nullptr;
 41 
 42 // The regenerated Klass is not added to any class loader, so we need
 43 // to keep its java_mirror alive to avoid class unloading.
 44 void RegeneratedClasses::add_class(InstanceKlass* orig_klass, InstanceKlass* regen_klass) {
 45   MutexLocker ml(DumpTimeTable_lock, Mutex::_no_safepoint_check_flag);
 46   if (_regenerated_mirrors == nullptr) {
 47     _regenerated_mirrors = new GrowableArrayCHeap<OopHandle, mtClassShared>(150);
 48   }
 49   _regenerated_mirrors->append(OopHandle(Universe::vm_global(), regen_klass->java_mirror()));
 50 
 51   if (_regenerated_objs == nullptr) {
 52     _regenerated_objs = new (mtClass)RegeneratedObjTable();
 53   }
 54   if (_original_objs == nullptr) {
 55     _original_objs = new (mtClass)RegeneratedObjTable();
 56   }
 57 
 58   _regenerated_objs->put((address)orig_klass, (address)regen_klass);
 59   _original_objs->put((address)regen_klass, (address)orig_klass);
 60   Array<Method*>* methods = orig_klass->methods();
 61   for (int i = 0; i < methods->length(); i++) {
 62     Method* orig_m = methods->at(i);
 63     Method* regen_m = regen_klass->find_method(orig_m->name(), orig_m->signature());
 64     if (regen_m == nullptr) {
 65       ResourceMark rm;
 66       if (orig_m->name() != vmSymbols::object_initializer_name()) {
 67         // JLI Holder classes are never instantiated, they don't need to have constructors.
 68         // Not printing the warning if the method is a constructor.
 69         log_warning(aot)("Method in original class is missing from regenerated class: " INTPTR_FORMAT " %s",
 70                          p2i(orig_m), orig_m->external_name());
 71       }
 72     } else {
 73       _regenerated_objs->put((address)orig_m, (address)regen_m);
 74       _original_objs->put((address)regen_m, (address)orig_m);
 75     }
 76   }
 77 
 78   if (log_is_enabled(Info, cds)) {
 79     ResourceMark rm;
 80     log_info(cds)("Regenerated class %s: methods %d -> %d)", orig_klass->external_name(),
 81                   orig_klass->methods()->length(), regen_klass->methods()->length());
 82   }
 83 }
 84 
 85 bool RegeneratedClasses::has_been_regenerated(address orig_obj) {
 86   if (_regenerated_objs == nullptr) {
 87     return false;
 88   } else {
 89     return _regenerated_objs->get(orig_obj) != nullptr;
 90   }
 91 }
 92 
 93 address RegeneratedClasses::get_regenerated_object(address orig_obj) {
 94   assert(_regenerated_objs != nullptr, "must be");
 95   address* p =_regenerated_objs->get(orig_obj);
 96   assert(p != nullptr, "must be");
 97   return *p;
 98 }
 99 
100 bool RegeneratedClasses::is_regenerated_object(address regen_obj) {
101   if (_original_objs == nullptr) {
102     return false;
103   } else {
104     return _original_objs->get(regen_obj) != nullptr;
105   }
106 }
107 
108 address RegeneratedClasses::get_original_object(address regen_obj) {
109   assert(_original_objs != nullptr, "must be");
110   address* p =_original_objs->get(regen_obj);
111   assert(p != nullptr, "must be");
112   return *p;
113 }
114 
115 void RegeneratedClasses::record_regenerated_objects() {
116   assert_locked_or_safepoint(DumpTimeTable_lock);
117   if (_regenerated_objs != nullptr) {
118     auto doit = [&] (address orig_obj, address regen_obj) {
119       ArchiveBuilder::current()->record_regenerated_object(orig_obj, regen_obj);
120     };
121     _regenerated_objs->iterate_all(doit);
122   }
123 }
124 
125 void RegeneratedClasses::cleanup() {
126   MutexLocker ml(DumpTimeTable_lock, Mutex::_no_safepoint_check_flag);
127   if (_regenerated_mirrors != nullptr) {
128     for (int i = 0; i < _regenerated_mirrors->length(); i++) {
129       _regenerated_mirrors->at(i).release(Universe::vm_global());
130     }
131     delete _regenerated_mirrors;
132     _regenerated_mirrors = nullptr;
133   }
134   if (_regenerated_objs != nullptr) {
135     delete _regenerated_objs;
136   }
137 }