1 /*
  2  * Copyright (c) 2001, 2018, 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_VM_GC_G1_G1BARRIERSET_HPP
 26 #define SHARE_VM_GC_G1_G1BARRIERSET_HPP
 27 
 28 #include "gc/g1/dirtyCardQueue.hpp"
 29 #include "gc/g1/satbMarkQueue.hpp"
 30 #include "gc/shared/cardTableBarrierSet.hpp"
 31 
 32 class DirtyCardQueueSet;
 33 class CardTable;
 34 class G1CardTable;
 35 
 36 // This barrier is specialized to use a logging barrier to support
 37 // snapshot-at-the-beginning marking.
 38 
 39 class G1BarrierSet: public CardTableBarrierSet {
 40   friend class VMStructs;
 41  private:
 42   static SATBMarkQueueSet  _satb_mark_queue_set;
 43   static DirtyCardQueueSet _dirty_card_queue_set;
 44 
 45  public:
 46   G1BarrierSet(G1CardTable* table);
 47   ~G1BarrierSet() { }
 48 
 49   // Add "pre_val" to a set of objects that may have been disconnected from the
 50   // pre-marking object graph.
 51   static void enqueue(oop pre_val);
 52 
 53   static void enqueue_if_weak_or_archive(DecoratorSet decorators, oop value);
 54 
 55   template <class T> void write_ref_array_pre_work(T* dst, size_t count);
 56   virtual void write_ref_array_pre(oop* dst, size_t count, bool dest_uninitialized);
 57   virtual void write_ref_array_pre(narrowOop* dst, size_t count, bool dest_uninitialized);
 58 
 59   template <DecoratorSet decorators, typename T>
 60   void write_ref_field_pre(T* field);
 61 
 62   // NB: if you do a whole-heap invalidation, the "usual invariant" defined
 63   // above no longer applies.
 64   void invalidate(MemRegion mr);
 65 
 66   void write_region(MemRegion mr)         { invalidate(mr); }
 67   void write_ref_array_work(MemRegion mr) { invalidate(mr); }
 68 
 69   template <DecoratorSet decorators, typename T>
 70   void write_ref_field_post(T* field, oop new_val);
 71   void write_ref_field_post_slow(volatile jbyte* byte);
 72 
 73   virtual void on_thread_create(Thread* thread);
 74   virtual void on_thread_destroy(Thread* thread);
 75   virtual void on_thread_attach(JavaThread* thread);
 76   virtual void on_thread_detach(JavaThread* thread);
 77 
 78   static SATBMarkQueueSet& satb_mark_queue_set() {
 79     return _satb_mark_queue_set;
 80   }
 81 
 82   static DirtyCardQueueSet& dirty_card_queue_set() {
 83     return _dirty_card_queue_set;
 84   }
 85 
 86   // Callbacks for runtime accesses.
 87   template <DecoratorSet decorators, typename BarrierSetT = G1BarrierSet>
 88   class AccessBarrier: public ModRefBarrierSet::AccessBarrier<decorators, BarrierSetT> {
 89     typedef ModRefBarrierSet::AccessBarrier<decorators, BarrierSetT> ModRef;
 90     typedef BarrierSet::AccessBarrier<decorators, BarrierSetT> Raw;
 91 
 92   public:
 93     // Needed for loads on non-heap weak references
 94     template <typename T>
 95     static oop oop_load_not_in_heap(T* addr);
 96 
 97     // Needed for non-heap stores
 98     template <typename T>
 99     static void oop_store_not_in_heap(T* addr, oop new_value);
100 
101     // Needed for weak references
102     static oop oop_load_in_heap_at(oop base, ptrdiff_t offset);
103 
104     // Defensive: will catch weak oops at addresses in heap
105     template <typename T>
106     static oop oop_load_in_heap(T* addr);
107   };
108 };
109 
110 template<>
111 struct BarrierSet::GetName<G1BarrierSet> {
112   static const BarrierSet::Name value = BarrierSet::G1BarrierSet;
113 };
114 
115 template<>
116 struct BarrierSet::GetType<BarrierSet::G1BarrierSet> {
117   typedef ::G1BarrierSet type;
118 };
119 
120 #endif // SHARE_VM_GC_G1_G1BARRIERSET_HPP