1 /*
   2  * Copyright (c) 2016, 2017, 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_G1SATBCARDTABLEMODREFBS_INLINE_HPP
  26 #define SHARE_VM_GC_G1_G1SATBCARDTABLEMODREFBS_INLINE_HPP
  27 
  28 #include "gc/shared/accessBarrierSupport.inline.hpp"
  29 #include "gc/g1/g1SATBCardTableModRefBS.hpp"
  30 #include "oops/oop.inline.hpp"
  31 
  32 template <DecoratorSet decorators, typename T>
  33 inline void G1SATBCardTableModRefBS::write_ref_field_pre(T* field) {
  34   if (HasDecorator<decorators, ARRAYCOPY_DEST_NOT_INITIALIZED>::value ||
  35       HasDecorator<decorators, AS_NO_KEEPALIVE>::value) {
  36     return;
  37   }
  38 
  39   T heap_oop = oopDesc::load_heap_oop(field);
  40   if (!oopDesc::is_null(heap_oop)) {
  41     enqueue(oopDesc::decode_heap_oop_not_null(heap_oop));
  42   }
  43 }
  44 
  45 template <DecoratorSet decorators, typename T>
  46 inline void G1SATBCardTableLoggingModRefBS::write_ref_field_post(T* field, oop new_val) {
  47   volatile jbyte* byte = byte_for(field);
  48   if (*byte != g1_young_gen) {
  49     // Take a slow path for cards in old
  50     write_ref_field_post_slow(byte);
  51   }
  52 }
  53 
  54 void G1SATBCardTableModRefBS::set_card_claimed(size_t card_index) {
  55   jbyte val = _byte_map[card_index];
  56   if (val == clean_card_val()) {
  57     val = (jbyte)claimed_card_val();
  58   } else {
  59     val |= (jbyte)claimed_card_val();
  60   }
  61   _byte_map[card_index] = val;
  62 }
  63 
  64 inline void G1SATBCardTableModRefBS::enqueue_if_weak_or_archive(DecoratorSet decorators, oop value) {
  65   assert((decorators & ON_UNKNOWN_OOP_REF) == 0, "Reference strength must be known");
  66   // Archive roots need to be enqueued since they add subgraphs to the
  67   // Java heap that were not there at the snapshot when marking started.
  68   // Weak and phantom references also need enqueueing for similar reasons.
  69   const bool in_archive_root   = (decorators & IN_ARCHIVE_ROOT) != 0;
  70   const bool on_strong_oop_ref = (decorators & ON_STRONG_OOP_REF) != 0;
  71   const bool peek              = (decorators & AS_NO_KEEPALIVE) != 0;
  72   const bool needs_enqueue     = in_archive_root || (!peek && !on_strong_oop_ref);
  73 
  74   if (needs_enqueue && value != NULL) {
  75     enqueue(value);
  76   }
  77 }
  78 
  79 template <DecoratorSet decorators, typename BarrierSetT>
  80 template <typename T>
  81 inline oop G1SATBCardTableLoggingModRefBS::AccessBarrier<decorators, BarrierSetT>::
  82 oop_load_not_in_heap(T* addr) {
  83   oop value = ModRef::oop_load_not_in_heap(addr);
  84   enqueue_if_weak_or_archive(decorators, value);
  85   return value;
  86 }
  87 
  88 template <DecoratorSet decorators, typename BarrierSetT>
  89 template <typename T>
  90 inline oop G1SATBCardTableLoggingModRefBS::AccessBarrier<decorators, BarrierSetT>::
  91 oop_load_in_heap(T* addr) {
  92   oop value = ModRef::oop_load_in_heap(addr);
  93   enqueue_if_weak_or_archive(decorators, value);
  94   return value;
  95 }
  96 
  97 template <DecoratorSet decorators, typename BarrierSetT>
  98 inline oop G1SATBCardTableLoggingModRefBS::AccessBarrier<decorators, BarrierSetT>::
  99 oop_load_in_heap_at(oop base, ptrdiff_t offset) {
 100   oop value = ModRef::oop_load_in_heap_at(base, offset);
 101   enqueue_if_weak_or_archive(AccessBarrierSupport::resolve_possibly_unknown_oop_ref_strength<decorators>(base, offset), value);
 102   return value;
 103 }
 104 
 105 template <DecoratorSet decorators, typename BarrierSetT>
 106 template <typename T>
 107 inline void G1SATBCardTableLoggingModRefBS::AccessBarrier<decorators, BarrierSetT>::
 108 oop_store_not_in_heap(T* addr, oop new_value) {
 109   if (HasDecorator<decorators, IN_CONCURRENT_ROOT>::value) {
 110     // For roots not scanned in a safepoint, we have to apply SATB barriers
 111     // even for roots.
 112     G1SATBCardTableLoggingModRefBS *bs = barrier_set_cast<G1SATBCardTableLoggingModRefBS>(BarrierSet::barrier_set());
 113     bs->write_ref_field_pre<decorators>(addr);
 114   }
 115   Raw::oop_store(addr, new_value);
 116 }
 117 
 118 #endif // SHARE_VM_GC_G1_G1SATBCARDTABLEMODREFBS_INLINE_HPP