1 /*
2 * Copyright (c) 2001, 2014, 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
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23 */
24
25 #ifndef SHARE_VM_GC_IMPLEMENTATION_G1_G1OOPCLOSURES_HPP
26 #define SHARE_VM_GC_IMPLEMENTATION_G1_G1OOPCLOSURES_HPP
27
28 class HeapRegion;
29 class G1CollectedHeap;
30 class G1RemSet;
31 class ConcurrentMark;
32 class DirtyCardToOopClosure;
33 class CMBitMap;
34 class CMMarkStack;
35 class G1ParScanThreadState;
36 class CMTask;
37 class ReferenceProcessor;
38
39 // A class that scans oops in a given heap region (much as OopsInGenClosure
40 // scans oops in a generation.)
41 class OopsInHeapRegionClosure: public ExtendedOopClosure {
42 protected:
43 HeapRegion* _from;
44 public:
45 void set_region(HeapRegion* from) { _from = from; }
46 };
47
48 class G1ParClosureSuper : public OopsInHeapRegionClosure {
49 protected:
50 G1CollectedHeap* _g1;
51 G1ParScanThreadState* _par_scan_state;
52 uint _worker_id;
53 public:
54 G1ParClosureSuper(G1CollectedHeap* g1, G1ParScanThreadState* par_scan_state);
55 bool apply_to_weak_ref_discovered_field() { return true; }
56 };
57
58 class G1ParPushHeapRSClosure : public G1ParClosureSuper {
59 public:
60 G1ParPushHeapRSClosure(G1CollectedHeap* g1,
61 G1ParScanThreadState* par_scan_state):
62 G1ParClosureSuper(g1, par_scan_state) { }
63
64 template <class T> void do_oop_nv(T* p);
65 virtual void do_oop(oop* p) { do_oop_nv(p); }
66 virtual void do_oop(narrowOop* p) { do_oop_nv(p); }
67 };
68
69 class G1ParScanClosure : public G1ParClosureSuper {
70 public:
71 G1ParScanClosure(G1CollectedHeap* g1, G1ParScanThreadState* par_scan_state, ReferenceProcessor* rp) :
72 G1ParClosureSuper(g1, par_scan_state)
73 {
74 assert(_ref_processor == NULL, "sanity");
75 _ref_processor = rp;
76 }
77
78 template <class T> void do_oop_nv(T* p);
79 virtual void do_oop(oop* p) { do_oop_nv(p); }
80 virtual void do_oop(narrowOop* p) { do_oop_nv(p); }
81 };
82
83 #define G1_PARTIAL_ARRAY_MASK 0x2
84
85 inline bool has_partial_array_mask(oop* ref) {
86 return ((uintptr_t)ref & G1_PARTIAL_ARRAY_MASK) == G1_PARTIAL_ARRAY_MASK;
87 }
88
89 // We never encode partial array oops as narrowOop*, so return false immediately.
90 // This allows the compiler to create optimized code when popping references from
91 // the work queue.
92 inline bool has_partial_array_mask(narrowOop* ref) {
93 assert(((uintptr_t)ref & G1_PARTIAL_ARRAY_MASK) != G1_PARTIAL_ARRAY_MASK, "Partial array oop reference encoded as narrowOop*");
94 return false;
95 }
96
97 // Only implement set_partial_array_mask() for regular oops, not for narrowOops.
98 // We always encode partial arrays as regular oop, to allow the
99 // specialization for has_partial_array_mask() for narrowOops above.
100 // This means that unintentional use of this method with narrowOops are caught
101 // by the compiler.
102 inline oop* set_partial_array_mask(oop obj) {
103 assert(((uintptr_t)(void *)obj & G1_PARTIAL_ARRAY_MASK) == 0, "Information loss!");
104 return (oop*) ((uintptr_t)(void *)obj | G1_PARTIAL_ARRAY_MASK);
105 }
106
107 template <class T> inline oop clear_partial_array_mask(T* ref) {
108 return cast_to_oop((intptr_t)ref & ~G1_PARTIAL_ARRAY_MASK);
109 }
110
111 class G1ParScanPartialArrayClosure : public G1ParClosureSuper {
112 G1ParScanClosure _scanner;
113
114 public:
115 G1ParScanPartialArrayClosure(G1CollectedHeap* g1, G1ParScanThreadState* par_scan_state, ReferenceProcessor* rp) :
116 G1ParClosureSuper(g1, par_scan_state), _scanner(g1, par_scan_state, rp)
117 {
118 assert(_ref_processor == NULL, "sanity");
119 }
120
121 G1ParScanClosure* scanner() {
122 return &_scanner;
123 }
124
125 template <class T> void do_oop_nv(T* p);
126 virtual void do_oop(oop* p) { do_oop_nv(p); }
127 virtual void do_oop(narrowOop* p) { do_oop_nv(p); }
128 };
129
130 // Add back base class for metadata
131 class G1ParCopyHelper : public G1ParClosureSuper {
132 protected:
133 Klass* _scanned_klass;
134 ConcurrentMark* _cm;
135
136 // Mark the object if it's not already marked. This is used to mark
137 // objects pointed to by roots that are guaranteed not to move
138 // during the GC (i.e., non-CSet objects). It is MT-safe.
139 void mark_object(oop obj);
140
141 // Mark the object if it's not already marked. This is used to mark
142 // objects pointed to by roots that have been forwarded during a
143 // GC. It is MT-safe.
144 void mark_forwarded_object(oop from_obj, oop to_obj);
145 public:
146 G1ParCopyHelper(G1CollectedHeap* g1, G1ParScanThreadState* par_scan_state);
147
148 void set_scanned_klass(Klass* k) { _scanned_klass = k; }
149 template <class T> void do_klass_barrier(T* p, oop new_obj);
150 };
151
152 template <G1Barrier barrier, bool do_mark_object>
153 class G1ParCopyClosure : public G1ParCopyHelper {
154 G1ParScanClosure _scanner;
155 template <class T> void do_oop_work(T* p);
156
157 protected:
158 oop copy_to_survivor_space(oop obj);
159
160 public:
161 G1ParCopyClosure(G1CollectedHeap* g1, G1ParScanThreadState* par_scan_state,
162 ReferenceProcessor* rp) :
163 _scanner(g1, par_scan_state, rp),
164 G1ParCopyHelper(g1, par_scan_state) {
165 assert(_ref_processor == NULL, "sanity");
166 }
167
168 G1ParScanClosure* scanner() { return &_scanner; }
169
170 template <class T> void do_oop_nv(T* p) { do_oop_work(p); }
171 virtual void do_oop(oop* p) { do_oop_nv(p); }
172 virtual void do_oop(narrowOop* p) { do_oop_nv(p); }
173 };
174
175 typedef G1ParCopyClosure<G1BarrierNone, false> G1ParScanExtRootClosure;
176 typedef G1ParCopyClosure<G1BarrierKlass, false> G1ParScanMetadataClosure;
177
178
179 typedef G1ParCopyClosure<G1BarrierNone, true> G1ParScanAndMarkExtRootClosure;
180 typedef G1ParCopyClosure<G1BarrierKlass, true> G1ParScanAndMarkMetadataClosure;
181
182 // The following closure type is defined in g1_specialized_oop_closures.hpp:
183 //
184 // typedef G1ParCopyClosure<G1BarrierEvac, false> G1ParScanHeapEvacClosure;
185
186 // We use a separate closure to handle references during evacuation
187 // failure processing.
188 // We could have used another instance of G1ParScanHeapEvacClosure
189 // (since that closure no longer assumes that the references it
190 // handles point into the collection set).
191
192 typedef G1ParCopyClosure<G1BarrierEvac, false> G1ParScanHeapEvacFailureClosure;
193
194 class FilterIntoCSClosure: public ExtendedOopClosure {
195 G1CollectedHeap* _g1;
196 OopClosure* _oc;
197 DirtyCardToOopClosure* _dcto_cl;
198 public:
199 FilterIntoCSClosure( DirtyCardToOopClosure* dcto_cl,
200 G1CollectedHeap* g1,
201 OopClosure* oc) :
202 _dcto_cl(dcto_cl), _g1(g1), _oc(oc) { }
203
204 template <class T> void do_oop_nv(T* p);
205 virtual void do_oop(oop* p) { do_oop_nv(p); }
206 virtual void do_oop(narrowOop* p) { do_oop_nv(p); }
207 bool apply_to_weak_ref_discovered_field() { return true; }
208 };
209
210 class FilterOutOfRegionClosure: public ExtendedOopClosure {
211 HeapWord* _r_bottom;
212 HeapWord* _r_end;
213 OopClosure* _oc;
214 public:
215 FilterOutOfRegionClosure(HeapRegion* r, OopClosure* oc);
216 template <class T> void do_oop_nv(T* p);
217 virtual void do_oop(oop* p) { do_oop_nv(p); }
218 virtual void do_oop(narrowOop* p) { do_oop_nv(p); }
219 bool apply_to_weak_ref_discovered_field() { return true; }
220 };
221
222 // Closure for iterating over object fields during concurrent marking
223 class G1CMOopClosure : public ExtendedOopClosure {
224 private:
225 G1CollectedHeap* _g1h;
226 ConcurrentMark* _cm;
227 CMTask* _task;
228 public:
229 G1CMOopClosure(G1CollectedHeap* g1h, ConcurrentMark* cm, CMTask* task);
230 template <class T> void do_oop_nv(T* p);
231 virtual void do_oop( oop* p) { do_oop_nv(p); }
232 virtual void do_oop(narrowOop* p) { do_oop_nv(p); }
233 };
234
235 // Closure to scan the root regions during concurrent marking
236 class G1RootRegionScanClosure : public ExtendedOopClosure {
237 private:
238 G1CollectedHeap* _g1h;
239 ConcurrentMark* _cm;
240 uint _worker_id;
241 public:
242 G1RootRegionScanClosure(G1CollectedHeap* g1h, ConcurrentMark* cm,
243 uint worker_id) :
244 _g1h(g1h), _cm(cm), _worker_id(worker_id) { }
245 template <class T> void do_oop_nv(T* p);
246 virtual void do_oop( oop* p) { do_oop_nv(p); }
247 virtual void do_oop(narrowOop* p) { do_oop_nv(p); }
248 };
249
250 // Closure that applies the given two closures in sequence.
251 // Used by the RSet refinement code (when updating RSets
252 // during an evacuation pause) to record cards containing
253 // pointers into the collection set.
254
255 class G1Mux2Closure : public ExtendedOopClosure {
256 OopClosure* _c1;
257 OopClosure* _c2;
258 public:
259 G1Mux2Closure(OopClosure *c1, OopClosure *c2);
260 template <class T> void do_oop_nv(T* p);
261 virtual void do_oop(oop* p) { do_oop_nv(p); }
262 virtual void do_oop(narrowOop* p) { do_oop_nv(p); }
263 };
264
265 // A closure that returns true if it is actually applied
266 // to a reference
267
268 class G1TriggerClosure : public ExtendedOopClosure {
269 bool _triggered;
270 public:
271 G1TriggerClosure();
272 bool triggered() const { return _triggered; }
273 template <class T> void do_oop_nv(T* p);
274 virtual void do_oop(oop* p) { do_oop_nv(p); }
275 virtual void do_oop(narrowOop* p) { do_oop_nv(p); }
276 };
277
278 // A closure which uses a triggering closure to determine
279 // whether to apply an oop closure.
280
281 class G1InvokeIfNotTriggeredClosure: public ExtendedOopClosure {
282 G1TriggerClosure* _trigger_cl;
283 OopClosure* _oop_cl;
284 public:
285 G1InvokeIfNotTriggeredClosure(G1TriggerClosure* t, OopClosure* oc);
286 template <class T> void do_oop_nv(T* p);
287 virtual void do_oop(oop* p) { do_oop_nv(p); }
288 virtual void do_oop(narrowOop* p) { do_oop_nv(p); }
289 };
290
291 class G1UpdateRSOrPushRefOopClosure: public ExtendedOopClosure {
292 G1CollectedHeap* _g1;
293 G1RemSet* _g1_rem_set;
294 HeapRegion* _from;
295 OopsInHeapRegionClosure* _push_ref_cl;
296 bool _record_refs_into_cset;
297 int _worker_i;
298
299 public:
300 G1UpdateRSOrPushRefOopClosure(G1CollectedHeap* g1h,
301 G1RemSet* rs,
302 OopsInHeapRegionClosure* push_ref_cl,
303 bool record_refs_into_cset,
304 int worker_i = 0);
305
306 void set_from(HeapRegion* from) {
307 assert(from != NULL, "from region must be non-NULL");
308 _from = from;
309 }
310
311 bool self_forwarded(oop obj) {
312 bool result = (obj->is_forwarded() && (obj->forwardee()== obj));
313 return result;
314 }
315
316 bool apply_to_weak_ref_discovered_field() { return true; }
317
318 template <class T> void do_oop_nv(T* p);
319 virtual void do_oop(narrowOop* p) { do_oop_nv(p); }
320 virtual void do_oop(oop* p) { do_oop_nv(p); }
321 };
322
323 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1OOPCLOSURES_HPP