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
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  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 G1SATBMarkQueueSet _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(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