1 /*
   2  * Copyright (c) 2001, 2013, 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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  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 OopsInGenClosure {
  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   G1RemSet* _g1_rem;
  52   ConcurrentMark* _cm;
  53   G1ParScanThreadState* _par_scan_state;
  54   uint _worker_id;
  55   bool _during_initial_mark;
  56   bool _mark_in_progress;
  57 public:
  58   G1ParClosureSuper(G1CollectedHeap* g1, G1ParScanThreadState* par_scan_state);
  59   bool apply_to_weak_ref_discovered_field() { return true; }
  60 };
  61 
  62 class G1ParPushHeapRSClosure : public G1ParClosureSuper {
  63 public:
  64   G1ParPushHeapRSClosure(G1CollectedHeap* g1,
  65                          G1ParScanThreadState* par_scan_state):
  66     G1ParClosureSuper(g1, par_scan_state) { }
  67 
  68   template <class T> void do_oop_nv(T* p);
  69   virtual void do_oop(oop* p)          { do_oop_nv(p); }
  70   virtual void do_oop(narrowOop* p)    { do_oop_nv(p); }
  71 };
  72 
  73 class G1ParScanClosure : public G1ParClosureSuper {
  74 public:
  75   G1ParScanClosure(G1CollectedHeap* g1, G1ParScanThreadState* par_scan_state, ReferenceProcessor* rp) :
  76     G1ParClosureSuper(g1, par_scan_state)
  77   {
  78     assert(_ref_processor == NULL, "sanity");
  79     _ref_processor = rp;
  80   }
  81 
  82   template <class T> void do_oop_nv(T* p);
  83   virtual void do_oop(oop* p)          { do_oop_nv(p); }
  84   virtual void do_oop(narrowOop* p)    { do_oop_nv(p); }
  85 };
  86 
  87 #define G1_PARTIAL_ARRAY_MASK 0x2
  88 
  89 template <class T> inline bool has_partial_array_mask(T* ref) {
  90   return ((uintptr_t)ref & G1_PARTIAL_ARRAY_MASK) == G1_PARTIAL_ARRAY_MASK;
  91 }
  92 
  93 template <class T> inline T* set_partial_array_mask(T obj) {
  94   assert(((uintptr_t)(void *)obj & G1_PARTIAL_ARRAY_MASK) == 0, "Information loss!");
  95   return (T*) ((uintptr_t)(void *)obj | G1_PARTIAL_ARRAY_MASK);
  96 }
  97 
  98 template <class T> inline oop clear_partial_array_mask(T* ref) {
  99   return cast_to_oop((intptr_t)ref & ~G1_PARTIAL_ARRAY_MASK);
 100 }
 101 
 102 class G1ParScanPartialArrayClosure : public G1ParClosureSuper {
 103   G1ParScanClosure _scanner;
 104 
 105 public:
 106   G1ParScanPartialArrayClosure(G1CollectedHeap* g1, G1ParScanThreadState* par_scan_state, ReferenceProcessor* rp) :
 107     G1ParClosureSuper(g1, par_scan_state), _scanner(g1, par_scan_state, rp)
 108   {
 109     assert(_ref_processor == NULL, "sanity");
 110   }
 111 
 112   G1ParScanClosure* scanner() {
 113     return &_scanner;
 114   }
 115 
 116   template <class T> void do_oop_nv(T* p);
 117   virtual void do_oop(oop* p)       { do_oop_nv(p); }
 118   virtual void do_oop(narrowOop* p) { do_oop_nv(p); }
 119 };
 120 
 121 // Add back base class for metadata
 122 class G1ParCopyHelper : public G1ParClosureSuper {
 123   Klass* _scanned_klass;
 124 
 125  public:
 126   G1ParCopyHelper(G1CollectedHeap* g1,  G1ParScanThreadState* par_scan_state) :
 127       _scanned_klass(NULL),
 128       G1ParClosureSuper(g1, par_scan_state) {}
 129 
 130   void set_scanned_klass(Klass* k) { _scanned_klass = k; }
 131   template <class T> void do_klass_barrier(T* p, oop new_obj);
 132 };
 133 
 134 template <bool do_gen_barrier, G1Barrier barrier, bool do_mark_object>
 135 class G1ParCopyClosure : public G1ParCopyHelper {
 136   G1ParScanClosure _scanner;
 137   template <class T> void do_oop_work(T* p);
 138 
 139 protected:
 140   // Mark the object if it's not already marked. This is used to mark
 141   // objects pointed to by roots that are guaranteed not to move
 142   // during the GC (i.e., non-CSet objects). It is MT-safe.
 143   void mark_object(oop obj);
 144 
 145   // Mark the object if it's not already marked. This is used to mark
 146   // objects pointed to by roots that have been forwarded during a
 147   // GC. It is MT-safe.
 148   void mark_forwarded_object(oop from_obj, oop to_obj);
 149 
 150   oop copy_to_survivor_space(oop obj);
 151 
 152 public:
 153   G1ParCopyClosure(G1CollectedHeap* g1, G1ParScanThreadState* par_scan_state,
 154                    ReferenceProcessor* rp) :
 155       _scanner(g1, par_scan_state, rp),
 156       G1ParCopyHelper(g1, par_scan_state) {
 157     assert(_ref_processor == NULL, "sanity");
 158   }
 159 
 160   G1ParScanClosure* scanner() { return &_scanner; }
 161 
 162   template <class T> void do_oop_nv(T* p) {
 163     do_oop_work(p);
 164   }
 165   virtual void do_oop(oop* p)       { do_oop_nv(p); }
 166   virtual void do_oop(narrowOop* p) { do_oop_nv(p); }
 167 };
 168 
 169 typedef G1ParCopyClosure<false, G1BarrierNone, false> G1ParScanExtRootClosure;
 170 typedef G1ParCopyClosure<false, G1BarrierKlass, false> G1ParScanMetadataClosure;
 171 
 172 
 173 typedef G1ParCopyClosure<false, G1BarrierNone, true> G1ParScanAndMarkExtRootClosure;
 174 typedef G1ParCopyClosure<true,  G1BarrierNone, true> G1ParScanAndMarkClosure;
 175 typedef G1ParCopyClosure<false, G1BarrierKlass, true> G1ParScanAndMarkMetadataClosure;
 176 
 177 // The following closure types are no longer used but are retained
 178 // for historical reasons:
 179 // typedef G1ParCopyClosure<false, G1BarrierRS,   false> G1ParScanHeapRSClosure;
 180 // typedef G1ParCopyClosure<false, G1BarrierRS,   true> G1ParScanAndMarkHeapRSClosure;
 181 
 182 // The following closure type is defined in g1_specialized_oop_closures.hpp:
 183 //
 184 // typedef G1ParCopyClosure<false, 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<false, 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