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/flatArrayKlass.inline.hpp"
36 #include "oops/instanceKlass.inline.hpp"
37 #include "oops/instanceMirrorKlass.inline.hpp"
38 #include "oops/instanceClassLoaderKlass.inline.hpp"
39 #include "oops/instanceRefKlass.inline.hpp"
40 #include "oops/instanceStackChunkKlass.inline.hpp"
41 #include "oops/objArrayKlass.inline.hpp"
42 #include "oops/typeArrayKlass.inline.hpp"
43 #include "utilities/debug.hpp"
44
45 // Defaults to strong claiming.
46 inline MetadataVisitingOopIterateClosure::MetadataVisitingOopIterateClosure(ReferenceDiscoverer* rd) :
47 ClaimMetadataVisitingOopIterateClosure(ClassLoaderData::_claim_strong, rd) {}
48
49 inline void ClaimMetadataVisitingOopIterateClosure::do_cld(ClassLoaderData* cld) {
50 cld->oops_do(this, _claim);
51 }
52
53 inline void ClaimMetadataVisitingOopIterateClosure::do_klass(Klass* k) {
54 ClassLoaderData* cld = k->class_loader_data();
55 ClaimMetadataVisitingOopIterateClosure::do_cld(cld);
56 }
57
58 inline void ClaimMetadataVisitingOopIterateClosure::do_nmethod(nmethod* nm) {
59 nm->follow_nmethod(this);
60 }
61
62 inline void ClaimMetadataVisitingOopIterateClosure::do_method(Method* m) {
63 // Mark interpreted frames for class redefinition
64 m->record_gc_epoch();
65 }
66
67 // Dispatch table implementation for *Klass::oop_oop_iterate
68 //
69 // It allows for a single call to do a multi-dispatch to an optimized version
70 // of oop_oop_iterate that statically know all these types:
71 // - OopClosureType : static type give at call site
72 // - Klass* : dynamic to static type through Klass::kind() -> table index
73 // - UseCompressedOops : dynamic to static value determined once
74 //
75 // when users call obj->oop_iterate(&cl).
76 //
77 // oopDesc::oop_iterate() calls OopOopIterateDispatch::function(klass)(cl, obj, klass),
78 // which dispatches to an optimized version of
79 // [Instance, ObjArry, etc]Klass::oop_oop_iterate(oop, OopClosureType)
80 //
81 // OopClosureType :
82 // If OopClosureType has an implementation of do_oop (and do_metadata et.al.),
83 // then the static type of OopClosureType will be used to allow inlining of
84 // do_oop (even though do_oop is virtual). Otherwise, a virtual call will be
85 // used when calling do_oop.
86 //
87 // Klass* :
88 // A table mapping from *Klass::Kind to function is setup. This happens once
89 // when the program starts, when the static _table instance is initialized for
90 // the OopOopIterateDispatch specialized with the OopClosureType.
91 //
92 // UseCompressedOops :
93 // Initially the table is populated with an init function, and not the actual
94 // oop_oop_iterate function. This is done, so that the first time we dispatch
95 // through the init function we check what the value of UseCompressedOops
96 // became, and use that to determine if we should install an optimized
97 // narrowOop version or optimized oop version of oop_oop_iterate. The appropriate
98 // oop_oop_iterate function replaces the init function in the table, and
99 // succeeding calls will jump directly to oop_oop_iterate.
100
101
102 template <typename OopClosureType>
103 class OopOopIterateDispatch : public AllStatic {
104 private:
105 typedef void (*FunctionType)(OopClosureType*, oop, Klass*);
106
107 class Table {
108 private:
109 template <typename KlassType, typename T>
110 static void oop_oop_iterate(OopClosureType* cl, oop obj, Klass* k) {
111 ((KlassType*)k)->KlassType::template oop_oop_iterate<T>(obj, cl);
112 }
113
114 template <typename KlassType>
115 static void init(OopClosureType* cl, oop obj, Klass* k) {
116 OopOopIterateDispatch<OopClosureType>::_table.set_resolve_function_and_execute<KlassType>(cl, obj, k);
117 }
118
119 template <typename KlassType>
120 void set_init_function() {
121 _function[KlassType::Kind] = &init<KlassType>;
122 }
123
124 template <typename KlassType>
125 void set_resolve_function() {
126 // Size requirement to prevent word tearing
127 // when functions pointers are updated.
128 STATIC_ASSERT(sizeof(_function[0]) == sizeof(void*));
129 if (UseCompressedOops) {
130 _function[KlassType::Kind] = &oop_oop_iterate<KlassType, narrowOop>;
131 } else {
132 _function[KlassType::Kind] = &oop_oop_iterate<KlassType, oop>;
133 }
134 }
135
136 template <typename KlassType>
137 void set_resolve_function_and_execute(OopClosureType* cl, oop obj, Klass* k) {
138 set_resolve_function<KlassType>();
139 _function[KlassType::Kind](cl, obj, k);
140 }
141
142 public:
143 FunctionType _function[Klass::KLASS_KIND_COUNT];
144
145 Table(){
146 set_init_function<InstanceKlass>();
147 set_init_function<InlineKlass>();
148 set_init_function<InstanceRefKlass>();
149 set_init_function<InstanceMirrorKlass>();
150 set_init_function<InstanceClassLoaderKlass>();
151 set_init_function<InstanceStackChunkKlass>();
152 set_init_function<ObjArrayKlass>();
153 set_init_function<TypeArrayKlass>();
154 set_init_function<FlatArrayKlass>();
155 }
156 };
157
158 static Table _table;
159 public:
160
161 static FunctionType function(Klass* klass) {
162 return _table._function[klass->kind()];
163 }
164 };
165
166 template <typename OopClosureType>
167 typename OopOopIterateDispatch<OopClosureType>::Table OopOopIterateDispatch<OopClosureType>::_table;
168
169
170 template <typename OopClosureType>
171 class OopOopIterateBoundedDispatch {
172 private:
173 typedef void (*FunctionType)(OopClosureType*, oop, Klass*, MemRegion);
174
175 class Table {
176 private:
177 template <typename KlassType, typename T>
178 static void oop_oop_iterate_bounded(OopClosureType* cl, oop obj, Klass* k, MemRegion mr) {
179 ((KlassType*)k)->KlassType::template oop_oop_iterate_bounded<T>(obj, cl, mr);
180 }
181
182 template <typename KlassType>
183 static void init(OopClosureType* cl, oop obj, Klass* k, MemRegion mr) {
184 OopOopIterateBoundedDispatch<OopClosureType>::_table.set_resolve_function_and_execute<KlassType>(cl, obj, k, mr);
185 }
186
187 template <typename KlassType>
188 void set_init_function() {
189 _function[KlassType::Kind] = &init<KlassType>;
190 }
191
192 template <typename KlassType>
193 void set_resolve_function() {
194 if (UseCompressedOops) {
195 _function[KlassType::Kind] = &oop_oop_iterate_bounded<KlassType, narrowOop>;
196 } else {
197 _function[KlassType::Kind] = &oop_oop_iterate_bounded<KlassType, oop>;
198 }
199 }
200
201 template <typename KlassType>
202 void set_resolve_function_and_execute(OopClosureType* cl, oop obj, Klass* k, MemRegion mr) {
203 set_resolve_function<KlassType>();
204 _function[KlassType::Kind](cl, obj, k, mr);
205 }
206
207 public:
208 FunctionType _function[Klass::KLASS_KIND_COUNT];
209
210 Table(){
211 set_init_function<InstanceKlass>();
212 set_init_function<InlineKlass>();
213 set_init_function<InstanceRefKlass>();
214 set_init_function<InstanceMirrorKlass>();
215 set_init_function<InstanceClassLoaderKlass>();
216 set_init_function<InstanceStackChunkKlass>();
217 set_init_function<ObjArrayKlass>();
218 set_init_function<TypeArrayKlass>();
219 set_init_function<FlatArrayKlass>();
220 }
221 };
222
223 static Table _table;
224 public:
225
226 static FunctionType function(Klass* klass) {
227 return _table._function[klass->kind()];
228 }
229 };
230
231 template <typename OopClosureType>
232 typename OopOopIterateBoundedDispatch<OopClosureType>::Table OopOopIterateBoundedDispatch<OopClosureType>::_table;
233
234
235 template <typename OopClosureType>
236 class OopOopIterateBackwardsDispatch {
237 private:
238 typedef void (*FunctionType)(OopClosureType*, oop, Klass*);
239
240 class Table {
241 private:
242 template <typename KlassType, typename T>
243 static void oop_oop_iterate_backwards(OopClosureType* cl, oop obj, Klass* k) {
244 ((KlassType*)k)->KlassType::template oop_oop_iterate_reverse<T>(obj, cl);
245 }
246
247 template <typename KlassType>
248 static void init(OopClosureType* cl, oop obj, Klass* k) {
249 OopOopIterateBackwardsDispatch<OopClosureType>::_table.set_resolve_function_and_execute<KlassType>(cl, obj, k);
250 }
251
252 template <typename KlassType>
253 void set_init_function() {
254 _function[KlassType::Kind] = &init<KlassType>;
255 }
256
257 template <typename KlassType>
258 void set_resolve_function() {
259 if (UseCompressedOops) {
260 _function[KlassType::Kind] = &oop_oop_iterate_backwards<KlassType, narrowOop>;
261 } else {
262 _function[KlassType::Kind] = &oop_oop_iterate_backwards<KlassType, oop>;
263 }
264 }
265
266 template <typename KlassType>
267 void set_resolve_function_and_execute(OopClosureType* cl, oop obj, Klass* k) {
268 set_resolve_function<KlassType>();
269 _function[KlassType::Kind](cl, obj, k);
270 }
271
272 public:
273 FunctionType _function[Klass::KLASS_KIND_COUNT];
274
275 Table(){
276 set_init_function<InstanceKlass>();
277 set_init_function<InlineKlass>();
278 set_init_function<InstanceRefKlass>();
279 set_init_function<InstanceMirrorKlass>();
280 set_init_function<InstanceClassLoaderKlass>();
281 set_init_function<InstanceStackChunkKlass>();
282 set_init_function<ObjArrayKlass>();
283 set_init_function<TypeArrayKlass>();
284 set_init_function<FlatArrayKlass>();
285 }
286 };
287
288 static Table _table;
289 public:
290
291 static FunctionType function(Klass* klass) {
292 return _table._function[klass->kind()];
293 }
294 };
295
296 template <typename OopClosureType>
297 typename OopOopIterateBackwardsDispatch<OopClosureType>::Table OopOopIterateBackwardsDispatch<OopClosureType>::_table;
298
299
300 template <typename OopClosureType>
301 void OopIteratorClosureDispatch::oop_oop_iterate(OopClosureType* cl, oop obj, Klass* klass) {
302 OopOopIterateDispatch<OopClosureType>::function(klass)(cl, obj, klass);
303 }
304
305 template <typename OopClosureType>
306 void OopIteratorClosureDispatch::oop_oop_iterate(OopClosureType* cl, oop obj, Klass* klass, MemRegion mr) {
307 OopOopIterateBoundedDispatch<OopClosureType>::function(klass)(cl, obj, klass, mr);
308 }
309
310 template <typename OopClosureType>
311 void OopIteratorClosureDispatch::oop_oop_iterate_backwards(OopClosureType* cl, oop obj, Klass* klass) {
312 OopOopIterateBackwardsDispatch<OopClosureType>::function(klass)(cl, obj, klass);
313 }
314
315 #endif // SHARE_MEMORY_ITERATOR_INLINE_HPP