1 /*
   2  * Copyright (c) 2001, 2011, 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.
  22  *
  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 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   bool _during_initial_mark;
  55   bool _mark_in_progress;
  56 public:
  57   G1ParClosureSuper(G1CollectedHeap* g1, G1ParScanThreadState* par_scan_state);
  58   bool apply_to_weak_ref_discovered_field() { return true; }
  59 };
  60 
  61 class G1ParPushHeapRSClosure : public G1ParClosureSuper {
  62 public:
  63   G1ParPushHeapRSClosure(G1CollectedHeap* g1,
  64                          G1ParScanThreadState* par_scan_state,
  65                          ReferenceProcessor* rp) :
  66     G1ParClosureSuper(g1, par_scan_state)
  67   {
  68     assert(_ref_processor == NULL, "sanity");
  69     _ref_processor = rp;
  70   }
  71 
  72   template <class T> void do_oop_nv(T* p);
  73   virtual void do_oop(oop* p)          { do_oop_nv(p); }
  74   virtual void do_oop(narrowOop* p)    { do_oop_nv(p); }
  75 };
  76 
  77 class G1ParScanClosure : public G1ParClosureSuper {
  78 public:
  79   G1ParScanClosure(G1CollectedHeap* g1, G1ParScanThreadState* par_scan_state, ReferenceProcessor* rp) :
  80     G1ParClosureSuper(g1, par_scan_state)
  81   {
  82     assert(_ref_processor == NULL, "sanity");
  83     _ref_processor = rp;
  84   }
  85 
  86   template <class T> void do_oop_nv(T* p);
  87   virtual void do_oop(oop* p)          { do_oop_nv(p); }
  88   virtual void do_oop(narrowOop* p)    { do_oop_nv(p); }
  89 };
  90 
  91 #define G1_PARTIAL_ARRAY_MASK 0x2
  92 
  93 template <class T> inline bool has_partial_array_mask(T* ref) {
  94   return ((uintptr_t)ref & G1_PARTIAL_ARRAY_MASK) == G1_PARTIAL_ARRAY_MASK;
  95 }
  96 
  97 template <class T> inline T* set_partial_array_mask(T obj) {
  98   assert(((uintptr_t)obj & G1_PARTIAL_ARRAY_MASK) == 0, "Information loss!");
  99   return (T*) ((uintptr_t)obj | G1_PARTIAL_ARRAY_MASK);
 100 }
 101 
 102 template <class T> inline oop clear_partial_array_mask(T* ref) {
 103   return oop((intptr_t)ref & ~G1_PARTIAL_ARRAY_MASK);
 104 }
 105 
 106 class G1ParScanPartialArrayClosure : public G1ParClosureSuper {
 107   G1ParScanClosure _scanner;
 108 
 109 public:
 110   G1ParScanPartialArrayClosure(G1CollectedHeap* g1, G1ParScanThreadState* par_scan_state, ReferenceProcessor* rp) :
 111     G1ParClosureSuper(g1, par_scan_state), _scanner(g1, par_scan_state, rp)
 112   {
 113     assert(_ref_processor == NULL, "sanity");
 114   }
 115 
 116   G1ParScanClosure* scanner() {
 117     return &_scanner;
 118   }
 119 
 120   template <class T> void do_oop_nv(T* p);
 121   virtual void do_oop(oop* p)       { do_oop_nv(p); }
 122   virtual void do_oop(narrowOop* p) { do_oop_nv(p); }
 123 };
 124 
 125 
 126 class G1ParCopyHelper : public G1ParClosureSuper {
 127   G1ParScanClosure *_scanner;
 128 protected:
 129   template <class T> void mark_object(T* p);
 130   oop copy_to_survivor_space(oop obj, bool should_mark_copy);
 131 public:
 132   G1ParCopyHelper(G1CollectedHeap* g1, G1ParScanThreadState* par_scan_state,
 133                   G1ParScanClosure *scanner) :
 134     G1ParClosureSuper(g1, par_scan_state), _scanner(scanner) { }
 135 };
 136 
 137 template<bool do_gen_barrier, G1Barrier barrier,
 138          bool do_mark_object>
 139 class G1ParCopyClosure : public G1ParCopyHelper {
 140   G1ParScanClosure _scanner;
 141 
 142   template <class T> void do_oop_work(T* p);
 143 
 144 public:
 145   G1ParCopyClosure(G1CollectedHeap* g1, G1ParScanThreadState* par_scan_state,
 146                    ReferenceProcessor* rp) :
 147     _scanner(g1, par_scan_state, rp),
 148     G1ParCopyHelper(g1, par_scan_state, &_scanner)
 149   {
 150     assert(_ref_processor == NULL, "sanity");
 151   }
 152 
 153   G1ParScanClosure* scanner() { return &_scanner; }
 154 
 155   template <class T> void do_oop_nv(T* p) {
 156     do_oop_work(p);
 157   }
 158   virtual void do_oop(oop* p)       { do_oop_nv(p); }
 159   virtual void do_oop(narrowOop* p) { do_oop_nv(p); }
 160 };
 161 
 162 typedef G1ParCopyClosure<false, G1BarrierNone, false> G1ParScanExtRootClosure;
 163 typedef G1ParCopyClosure<true,  G1BarrierNone, false> G1ParScanPermClosure;
 164 
 165 typedef G1ParCopyClosure<false, G1BarrierNone, true> G1ParScanAndMarkExtRootClosure;
 166 typedef G1ParCopyClosure<true,  G1BarrierNone, true> G1ParScanAndMarkPermClosure;
 167 
 168 // The following closure types are no longer used but are retained
 169 // for historical reasons:
 170 // typedef G1ParCopyClosure<false, G1BarrierRS,   false> G1ParScanHeapRSClosure;
 171 // typedef G1ParCopyClosure<false, G1BarrierRS,   true> G1ParScanAndMarkHeapRSClosure;
 172 
 173 // The following closure type is defined in g1_specialized_oop_closures.hpp:
 174 //
 175 // typedef G1ParCopyClosure<false, G1BarrierEvac, false> G1ParScanHeapEvacClosure;
 176 
 177 // We use a separate closure to handle references during evacuation
 178 // failure processing.
 179 // We could have used another instance of G1ParScanHeapEvacClosure
 180 // (since that closure no longer assumes that the references it
 181 // handles point into the collection set).
 182 
 183 typedef G1ParCopyClosure<false, G1BarrierEvac, false> G1ParScanHeapEvacFailureClosure;
 184 
 185 class FilterIntoCSClosure: public OopClosure {
 186   G1CollectedHeap* _g1;
 187   OopClosure* _oc;
 188   DirtyCardToOopClosure* _dcto_cl;
 189 public:
 190   FilterIntoCSClosure(  DirtyCardToOopClosure* dcto_cl,
 191                         G1CollectedHeap* g1,
 192                         OopClosure* oc,
 193                         ReferenceProcessor* rp) :
 194     _dcto_cl(dcto_cl), _g1(g1), _oc(oc)
 195   {
 196     assert(_ref_processor == NULL, "sanity");
 197     _ref_processor = rp;
 198   }
 199 
 200   template <class T> void do_oop_nv(T* p);
 201   virtual void do_oop(oop* p)        { do_oop_nv(p); }
 202   virtual void do_oop(narrowOop* p)  { do_oop_nv(p); }
 203   bool apply_to_weak_ref_discovered_field() { return true; }
 204   bool do_header() { return false; }
 205 };
 206 
 207 class FilterOutOfRegionClosure: public OopClosure {
 208   HeapWord* _r_bottom;
 209   HeapWord* _r_end;
 210   OopClosure* _oc;
 211   int _out_of_region;
 212 public:
 213   FilterOutOfRegionClosure(HeapRegion* r, OopClosure* oc);
 214   template <class T> void do_oop_nv(T* p);
 215   virtual void do_oop(oop* p) { do_oop_nv(p); }
 216   virtual void do_oop(narrowOop* p) { do_oop_nv(p); }
 217   bool apply_to_weak_ref_discovered_field() { return true; }
 218   bool do_header() { return false; }
 219   int out_of_region() { return _out_of_region; }
 220 };
 221 
 222 // Closure for iterating over object fields during concurrent marking
 223 class G1CMOopClosure : public OopClosure {
 224   G1CollectedHeap*   _g1h;
 225   ConcurrentMark*    _cm;
 226   CMTask*            _task;
 227 public:
 228   G1CMOopClosure(G1CollectedHeap* g1h, ConcurrentMark* cm, CMTask* task);
 229   template <class T> void do_oop_nv(T* p);
 230   virtual void do_oop(      oop* p) { do_oop_nv(p); }
 231   virtual void do_oop(narrowOop* p) { do_oop_nv(p); }
 232 };
 233 
 234 #endif // SHARE_VM_GC_IMPLEMENTATION_G1_G1OOPCLOSURES_HPP