1 /*
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  3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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  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
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 24 
 25 #ifndef SHARE_VM_GC_G1_G1BARRIERSET_INLINE_HPP
 26 #define SHARE_VM_GC_G1_G1BARRIERSET_INLINE_HPP
 27 
 28 #include "gc/g1/g1BarrierSet.hpp"
 29 #include "gc/g1/g1CardTable.hpp"
 30 #include "gc/shared/accessBarrierSupport.inline.hpp"
 31 
 32 template <DecoratorSet decorators, typename T>
 33 inline void G1BarrierSet::write_ref_field_pre(T* field) {
 34   if (HasDecorator<decorators, AS_DEST_NOT_INITIALIZED>::value ||
 35       HasDecorator<decorators, AS_NO_KEEPALIVE>::value) {
 36     return;
 37   }
 38 
 39   oop heap_oop = RawAccess<MO_VOLATILE>::oop_load(field);
 40   if (heap_oop != NULL) {
 41     enqueue(heap_oop);
 42   }
 43 }
 44 
 45 template <DecoratorSet decorators, typename T>
 46 inline void G1BarrierSet::write_ref_field_post(T* field, oop new_val) {
 47   volatile jbyte* byte = _card_table->byte_for(field);
 48   if (*byte != G1CardTable::g1_young_card_val()) {
 49     // Take a slow path for cards in old
 50     write_ref_field_post_slow(byte);
 51   }
 52 }
 53 
 54 inline void G1BarrierSet::enqueue_if_weak_or_archive(DecoratorSet decorators, oop value) {
 55   assert((decorators & ON_UNKNOWN_OOP_REF) == 0, "Reference strength must be known");
 56   // Archive roots need to be enqueued since they add subgraphs to the
 57   // Java heap that were not there at the snapshot when marking started.
 58   // Weak and phantom references also need enqueueing for similar reasons.
 59   const bool in_archive_root   = (decorators & IN_ARCHIVE_ROOT) != 0;
 60   const bool on_strong_oop_ref = (decorators & ON_STRONG_OOP_REF) != 0;
 61   const bool peek              = (decorators & AS_NO_KEEPALIVE) != 0;
 62   const bool needs_enqueue     = in_archive_root || (!peek && !on_strong_oop_ref);
 63 
 64   if (needs_enqueue && value != NULL) {
 65     enqueue(value);
 66   }
 67 }
 68 
 69 template <DecoratorSet decorators, typename BarrierSetT>
 70 template <typename T>
 71 inline oop G1BarrierSet::AccessBarrier<decorators, BarrierSetT>::
 72 oop_load_not_in_heap(T* addr) {
 73   oop value = ModRef::oop_load_not_in_heap(addr);
 74   enqueue_if_weak_or_archive(decorators, value);
 75   return value;
 76 }
 77 
 78 template <DecoratorSet decorators, typename BarrierSetT>
 79 template <typename T>
 80 inline oop G1BarrierSet::AccessBarrier<decorators, BarrierSetT>::
 81 oop_load_in_heap(T* addr) {
 82   oop value = ModRef::oop_load_in_heap(addr);
 83   enqueue_if_weak_or_archive(decorators, value);
 84   return value;
 85 }
 86 
 87 template <DecoratorSet decorators, typename BarrierSetT>
 88 inline oop G1BarrierSet::AccessBarrier<decorators, BarrierSetT>::
 89 oop_load_in_heap_at(oop base, ptrdiff_t offset) {
 90   oop value = ModRef::oop_load_in_heap_at(base, offset);
 91   enqueue_if_weak_or_archive(AccessBarrierSupport::resolve_possibly_unknown_oop_ref_strength<decorators>(base, offset), value);
 92   return value;
 93 }
 94 
 95 template <DecoratorSet decorators, typename BarrierSetT>
 96 template <typename T>
 97 inline void G1BarrierSet::AccessBarrier<decorators, BarrierSetT>::
 98 oop_store_not_in_heap(T* addr, oop new_value) {
 99   if (HasDecorator<decorators, IN_CONCURRENT_ROOT>::value) {
100     // For roots not scanned in a safepoint, we have to apply SATB barriers
101     // even for roots.
102     G1BarrierSet *bs = barrier_set_cast<G1BarrierSet>(BarrierSet::barrier_set());
103     bs->write_ref_field_pre<decorators>(addr);
104   }
105   Raw::oop_store(addr, new_value);
106 }
107 
108 #endif // SHARE_VM_GC_G1_G1BARRIERSET_INLINE_HPP