1 /*
  2  * Copyright (c) 2015, 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.
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 23  */
 24 
 25 #ifndef SHARE_OOPS_INSTANCEKLASS_INLINE_HPP
 26 #define SHARE_OOPS_INSTANCEKLASS_INLINE_HPP
 27 
 28 #include "oops/instanceKlass.hpp"
 29 
 30 #include "memory/memRegion.hpp"
 31 #include "oops/fieldInfo.inline.hpp"
 32 #include "oops/klass.inline.hpp"
 33 #include "oops/oop.inline.hpp"
 34 #include "runtime/atomic.hpp"
 35 #include "utilities/devirtualizer.inline.hpp"
 36 #include "utilities/globalDefinitions.hpp"
 37 
 38 inline intptr_t* InstanceKlass::start_of_itable()   const { return (intptr_t*)start_of_vtable() + vtable_length(); }
 39 inline intptr_t* InstanceKlass::end_of_itable()     const { return start_of_itable() + itable_length(); }
 40 
 41 inline oop InstanceKlass::static_field_base_raw() { return java_mirror(); }
 42 
 43 inline Symbol* InstanceKlass::field_name(int index) const { return field(index).name(constants()); }
 44 inline Symbol* InstanceKlass::field_signature(int index) const { return field(index).signature(constants()); }
 45 
 46 inline int InstanceKlass::java_fields_count() const { return FieldInfoStream::num_java_fields(fieldinfo_stream()); }
 47 inline int InstanceKlass::total_fields_count() const { return FieldInfoStream::num_total_fields(fieldinfo_stream()); }
 48 
 49 inline OopMapBlock* InstanceKlass::start_of_nonstatic_oop_maps() const {
 50   return (OopMapBlock*)(start_of_itable() + itable_length());
 51 }
 52 
 53 inline Klass** InstanceKlass::end_of_nonstatic_oop_maps() const {
 54   return (Klass**)(start_of_nonstatic_oop_maps() +
 55                    nonstatic_oop_map_count());
 56 }
 57 
 58 inline InstanceKlass* volatile* InstanceKlass::adr_implementor() const {
 59   if (is_interface()) {
 60     return (InstanceKlass* volatile*)end_of_nonstatic_oop_maps();
 61   } else {
 62     return nullptr;
 63   }
 64 }
 65 
 66 inline InlineKlass* InstanceKlass::get_inline_type_field_klass(int idx) const {
 67   assert(has_inline_type_fields(), "Sanity checking");
 68   assert(idx < java_fields_count(), "IOOB");
 69   InlineKlass* k = inline_layout_info(idx).klass();
 70   assert(k != nullptr, "Should always be set before being read");
 71   return k;
 72 }
 73 
 74 inline InlineKlass* InstanceKlass::get_inline_type_field_klass_or_null(int idx) const {
 75   assert(has_inline_type_fields(), "Sanity checking");
 76   assert(idx < java_fields_count(), "IOOB");
 77   InlineKlass* k = inline_layout_info(idx).klass();
 78   return k;
 79 }
 80 
 81 inline ObjArrayKlass* InstanceKlass::array_klasses_acquire() const {
 82   return Atomic::load_acquire(&_array_klasses);
 83 }
 84 
 85 inline void InstanceKlass::release_set_array_klasses(ObjArrayKlass* k) {
 86   Atomic::release_store(&_array_klasses, k);
 87 }
 88 
 89 // The iteration over the oops in objects is a hot path in the GC code.
 90 // By force inlining the following functions, we get similar GC performance
 91 // as the previous macro based implementation.
 92 
 93 template <typename T, class OopClosureType>
 94 ALWAYSINLINE void InstanceKlass::oop_oop_iterate_oop_map(OopMapBlock* map, oop obj, OopClosureType* closure) {
 95   T* p         = obj->field_addr<T>(map->offset());
 96   T* const end = p + map->count();
 97 
 98   for (; p < end; ++p) {
 99     Devirtualizer::do_oop(closure, p);
100   }
101 }
102 
103 template <typename T, class OopClosureType>
104 ALWAYSINLINE void InstanceKlass::oop_oop_iterate_oop_map_reverse(OopMapBlock* map, oop obj, OopClosureType* closure) {
105   T* const start = obj->field_addr<T>(map->offset());
106   T*       p     = start + map->count();
107 
108   while (start < p) {
109     --p;
110     Devirtualizer::do_oop(closure, p);
111   }
112 }
113 
114 template <typename T, class OopClosureType>
115 ALWAYSINLINE void InstanceKlass::oop_oop_iterate_oop_map_bounded(OopMapBlock* map, oop obj, OopClosureType* closure, MemRegion mr) {
116   T* p   = obj->field_addr<T>(map->offset());
117   T* end = p + map->count();
118 
119   T* const l   = (T*)mr.start();
120   T* const h   = (T*)mr.end();
121   assert(mask_bits((intptr_t)l, sizeof(T)-1) == 0 &&
122          mask_bits((intptr_t)h, sizeof(T)-1) == 0,
123          "bounded region must be properly aligned");
124 
125   if (p < l) {
126     p = l;
127   }
128   if (end > h) {
129     end = h;
130   }
131 
132   for (;p < end; ++p) {
133     Devirtualizer::do_oop(closure, p);
134   }
135 }
136 
137 template <typename T, class OopClosureType>
138 ALWAYSINLINE void InstanceKlass::oop_oop_iterate_oop_maps(oop obj, OopClosureType* closure) {
139   OopMapBlock* map           = start_of_nonstatic_oop_maps();
140   OopMapBlock* const end_map = map + nonstatic_oop_map_count();
141 
142   for (; map < end_map; ++map) {
143     oop_oop_iterate_oop_map<T>(map, obj, closure);
144   }
145 }
146 
147 template <typename T, class OopClosureType>
148 ALWAYSINLINE void InstanceKlass::oop_oop_iterate_oop_maps_reverse(oop obj, OopClosureType* closure) {
149   OopMapBlock* const start_map = start_of_nonstatic_oop_maps();
150   OopMapBlock* map             = start_map + nonstatic_oop_map_count();
151 
152   while (start_map < map) {
153     --map;
154     oop_oop_iterate_oop_map_reverse<T>(map, obj, closure);
155   }
156 }
157 
158 template <typename T, class OopClosureType>
159 ALWAYSINLINE void InstanceKlass::oop_oop_iterate_oop_maps_bounded(oop obj, OopClosureType* closure, MemRegion mr) {
160   OopMapBlock* map           = start_of_nonstatic_oop_maps();
161   OopMapBlock* const end_map = map + nonstatic_oop_map_count();
162 
163   for (;map < end_map; ++map) {
164     oop_oop_iterate_oop_map_bounded<T>(map, obj, closure, mr);
165   }
166 }
167 
168 template <typename T, class OopClosureType>
169 ALWAYSINLINE void InstanceKlass::oop_oop_iterate(oop obj, OopClosureType* closure) {
170   if (Devirtualizer::do_metadata(closure)) {
171     Devirtualizer::do_klass(closure, this);
172   }
173 
174   oop_oop_iterate_oop_maps<T>(obj, closure);
175 }
176 
177 template <typename T, class OopClosureType>
178 ALWAYSINLINE void InstanceKlass::oop_oop_iterate_reverse(oop obj, OopClosureType* closure) {
179   assert(!Devirtualizer::do_metadata(closure),
180       "Code to handle metadata is not implemented");
181 
182   oop_oop_iterate_oop_maps_reverse<T>(obj, closure);
183 }
184 
185 template <typename T, class OopClosureType>
186 ALWAYSINLINE void InstanceKlass::oop_oop_iterate_bounded(oop obj, OopClosureType* closure, MemRegion mr) {
187   if (Devirtualizer::do_metadata(closure)) {
188     if (mr.contains(obj)) {
189       Devirtualizer::do_klass(closure, this);
190     }
191   }
192 
193   oop_oop_iterate_oop_maps_bounded<T>(obj, closure, mr);
194 }
195 
196 #endif // SHARE_OOPS_INSTANCEKLASS_INLINE_HPP