1 /*
2 * Copyright (c) 2014, 2023, 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_MEMORY_ITERATOR_INLINE_HPP
26 #define SHARE_MEMORY_ITERATOR_INLINE_HPP
27
28 #include "memory/iterator.hpp"
29
30 #include "classfile/classLoaderData.hpp"
31 #include "code/nmethod.hpp"
32 #include "oops/access.inline.hpp"
33 #include "oops/compressedOops.inline.hpp"
34 #include "oops/klass.hpp"
35 #include "oops/instanceKlass.inline.hpp"
36 #include "oops/instanceMirrorKlass.inline.hpp"
37 #include "oops/instanceClassLoaderKlass.inline.hpp"
38 #include "oops/instanceRefKlass.inline.hpp"
39 #include "oops/instanceStackChunkKlass.inline.hpp"
40 #include "oops/objArrayKlass.inline.hpp"
41 #include "oops/typeArrayKlass.inline.hpp"
42 #include "utilities/debug.hpp"
43
44 // Defaults to strong claiming.
45 inline MetadataVisitingOopIterateClosure::MetadataVisitingOopIterateClosure(ReferenceDiscoverer* rd) :
46 ClaimMetadataVisitingOopIterateClosure(ClassLoaderData::_claim_strong, rd) {}
47
48 inline void ClaimMetadataVisitingOopIterateClosure::do_cld(ClassLoaderData* cld) {
49 cld->oops_do(this, _claim);
50 }
51
52 inline void ClaimMetadataVisitingOopIterateClosure::do_klass(Klass* k) {
53 ClassLoaderData* cld = k->class_loader_data();
54 ClaimMetadataVisitingOopIterateClosure::do_cld(cld);
55 }
56
57 inline void ClaimMetadataVisitingOopIterateClosure::do_nmethod(nmethod* nm) {
58 nm->follow_nmethod(this);
59 }
60
61 inline void ClaimMetadataVisitingOopIterateClosure::do_method(Method* m) {
62 // Mark interpreted frames for class redefinition
63 m->record_gc_epoch();
64 }
65
66 // Dispatch table implementation for *Klass::oop_oop_iterate
67 //
68 // It allows for a single call to do a multi-dispatch to an optimized version
69 // of oop_oop_iterate that statically know all these types:
70 // - OopClosureType : static type give at call site
71 // - Klass* : dynamic to static type through Klass::kind() -> table index
72 // - UseCompressedOops : dynamic to static value determined once
73 //
74 // when users call obj->oop_iterate(&cl).
75 //
76 // oopDesc::oop_iterate() calls OopOopIterateDispatch::function(klass)(cl, obj, klass),
77 // which dispatches to an optimized version of
78 // [Instance, ObjArry, etc]Klass::oop_oop_iterate(oop, OopClosureType)
79 //
80 // OopClosureType :
81 // If OopClosureType has an implementation of do_oop (and do_metadata et.al.),
82 // then the static type of OopClosureType will be used to allow inlining of
83 // do_oop (even though do_oop is virtual). Otherwise, a virtual call will be
84 // used when calling do_oop.
85 //
86 // Klass* :
87 // A table mapping from *Klass::Kind to function is setup. This happens once
88 // when the program starts, when the static _table instance is initialized for
89 // the OopOopIterateDispatch specialized with the OopClosureType.
90 //
91 // UseCompressedOops :
92 // Initially the table is populated with an init function, and not the actual
93 // oop_oop_iterate function. This is done, so that the first time we dispatch
94 // through the init function we check what the value of UseCompressedOops
95 // became, and use that to determine if we should install an optimized
96 // narrowOop version or optimized oop version of oop_oop_iterate. The appropriate
97 // oop_oop_iterate function replaces the init function in the table, and
98 // succeeding calls will jump directly to oop_oop_iterate.
99
100
101 template <typename OopClosureType>
102 class OopOopIterateDispatch : public AllStatic {
103 private:
104 typedef void (*FunctionType)(OopClosureType*, oop, Klass*);
105
106 class Table {
107 private:
108 template <typename KlassType, typename T>
109 static void oop_oop_iterate(OopClosureType* cl, oop obj, Klass* k) {
110 ((KlassType*)k)->KlassType::template oop_oop_iterate<T>(obj, cl);
111 }
112
113 template <typename KlassType>
114 static void init(OopClosureType* cl, oop obj, Klass* k) {
115 OopOopIterateDispatch<OopClosureType>::_table.set_resolve_function_and_execute<KlassType>(cl, obj, k);
116 }
117
118 template <typename KlassType>
119 void set_init_function() {
120 _function[KlassType::Kind] = &init<KlassType>;
121 }
122
123 template <typename KlassType>
124 void set_resolve_function() {
125 // Size requirement to prevent word tearing
126 // when functions pointers are updated.
127 STATIC_ASSERT(sizeof(_function[0]) == sizeof(void*));
128 if (UseCompressedOops) {
129 _function[KlassType::Kind] = &oop_oop_iterate<KlassType, narrowOop>;
130 } else {
131 _function[KlassType::Kind] = &oop_oop_iterate<KlassType, oop>;
132 }
133 }
134
135 template <typename KlassType>
136 void set_resolve_function_and_execute(OopClosureType* cl, oop obj, Klass* k) {
137 set_resolve_function<KlassType>();
138 _function[KlassType::Kind](cl, obj, k);
139 }
140
141 public:
142 FunctionType _function[Klass::KLASS_KIND_COUNT];
143
144 Table(){
145 set_init_function<InstanceKlass>();
146 set_init_function<InstanceRefKlass>();
147 set_init_function<InstanceMirrorKlass>();
148 set_init_function<InstanceClassLoaderKlass>();
149 set_init_function<InstanceStackChunkKlass>();
150 set_init_function<ObjArrayKlass>();
151 set_init_function<TypeArrayKlass>();
152 }
153 };
154
155 static Table _table;
156 public:
157
158 static FunctionType function(Klass* klass) {
159 return _table._function[klass->kind()];
160 }
161 };
162
163 template <typename OopClosureType>
164 typename OopOopIterateDispatch<OopClosureType>::Table OopOopIterateDispatch<OopClosureType>::_table;
165
166
167 template <typename OopClosureType>
168 class OopOopIterateBoundedDispatch {
169 private:
170 typedef void (*FunctionType)(OopClosureType*, oop, Klass*, MemRegion);
171
172 class Table {
173 private:
174 template <typename KlassType, typename T>
175 static void oop_oop_iterate_bounded(OopClosureType* cl, oop obj, Klass* k, MemRegion mr) {
176 ((KlassType*)k)->KlassType::template oop_oop_iterate_bounded<T>(obj, cl, mr);
177 }
178
179 template <typename KlassType>
180 static void init(OopClosureType* cl, oop obj, Klass* k, MemRegion mr) {
181 OopOopIterateBoundedDispatch<OopClosureType>::_table.set_resolve_function_and_execute<KlassType>(cl, obj, k, mr);
182 }
183
184 template <typename KlassType>
185 void set_init_function() {
186 _function[KlassType::Kind] = &init<KlassType>;
187 }
188
189 template <typename KlassType>
190 void set_resolve_function() {
191 if (UseCompressedOops) {
192 _function[KlassType::Kind] = &oop_oop_iterate_bounded<KlassType, narrowOop>;
193 } else {
194 _function[KlassType::Kind] = &oop_oop_iterate_bounded<KlassType, oop>;
195 }
196 }
197
198 template <typename KlassType>
199 void set_resolve_function_and_execute(OopClosureType* cl, oop obj, Klass* k, MemRegion mr) {
200 set_resolve_function<KlassType>();
201 _function[KlassType::Kind](cl, obj, k, mr);
202 }
203
204 public:
205 FunctionType _function[Klass::KLASS_KIND_COUNT];
206
207 Table(){
208 set_init_function<InstanceKlass>();
209 set_init_function<InstanceRefKlass>();
210 set_init_function<InstanceMirrorKlass>();
211 set_init_function<InstanceClassLoaderKlass>();
212 set_init_function<InstanceStackChunkKlass>();
213 set_init_function<ObjArrayKlass>();
214 set_init_function<TypeArrayKlass>();
215 }
216 };
217
218 static Table _table;
219 public:
220
221 static FunctionType function(Klass* klass) {
222 return _table._function[klass->kind()];
223 }
224 };
225
226 template <typename OopClosureType>
227 typename OopOopIterateBoundedDispatch<OopClosureType>::Table OopOopIterateBoundedDispatch<OopClosureType>::_table;
228
229
230 template <typename OopClosureType>
231 class OopOopIterateBackwardsDispatch {
232 private:
233 typedef void (*FunctionType)(OopClosureType*, oop, Klass*);
234
235 class Table {
236 private:
237 template <typename KlassType, typename T>
238 static void oop_oop_iterate_backwards(OopClosureType* cl, oop obj, Klass* k) {
239 ((KlassType*)k)->KlassType::template oop_oop_iterate_reverse<T>(obj, cl);
240 }
241
242 template <typename KlassType>
243 static void init(OopClosureType* cl, oop obj, Klass* k) {
244 OopOopIterateBackwardsDispatch<OopClosureType>::_table.set_resolve_function_and_execute<KlassType>(cl, obj, k);
245 }
246
247 template <typename KlassType>
248 void set_init_function() {
249 _function[KlassType::Kind] = &init<KlassType>;
250 }
251
252 template <typename KlassType>
253 void set_resolve_function() {
254 if (UseCompressedOops) {
255 _function[KlassType::Kind] = &oop_oop_iterate_backwards<KlassType, narrowOop>;
256 } else {
257 _function[KlassType::Kind] = &oop_oop_iterate_backwards<KlassType, oop>;
258 }
259 }
260
261 template <typename KlassType>
262 void set_resolve_function_and_execute(OopClosureType* cl, oop obj, Klass* k) {
263 set_resolve_function<KlassType>();
264 _function[KlassType::Kind](cl, obj, k);
265 }
266
267 public:
268 FunctionType _function[Klass::KLASS_KIND_COUNT];
269
270 Table(){
271 set_init_function<InstanceKlass>();
272 set_init_function<InstanceRefKlass>();
273 set_init_function<InstanceMirrorKlass>();
274 set_init_function<InstanceClassLoaderKlass>();
275 set_init_function<InstanceStackChunkKlass>();
276 set_init_function<ObjArrayKlass>();
277 set_init_function<TypeArrayKlass>();
278 }
279 };
280
281 static Table _table;
282 public:
283
284 static FunctionType function(Klass* klass) {
285 return _table._function[klass->kind()];
286 }
287 };
288
289 template <typename OopClosureType>
290 typename OopOopIterateBackwardsDispatch<OopClosureType>::Table OopOopIterateBackwardsDispatch<OopClosureType>::_table;
291
292
293 template <typename OopClosureType>
294 void OopIteratorClosureDispatch::oop_oop_iterate(OopClosureType* cl, oop obj, Klass* klass) {
295 OopOopIterateDispatch<OopClosureType>::function(klass)(cl, obj, klass);
296 }
297
298 template <typename OopClosureType>
299 void OopIteratorClosureDispatch::oop_oop_iterate(OopClosureType* cl, oop obj, Klass* klass, MemRegion mr) {
300 OopOopIterateBoundedDispatch<OopClosureType>::function(klass)(cl, obj, klass, mr);
301 }
302
303 template <typename OopClosureType>
304 void OopIteratorClosureDispatch::oop_oop_iterate_backwards(OopClosureType* cl, oop obj, Klass* klass) {
305 OopOopIterateBackwardsDispatch<OopClosureType>::function(klass)(cl, obj, klass);
306 }
307
308 #endif // SHARE_MEMORY_ITERATOR_INLINE_HPP