1 /* 2 * Copyright (c) 2000, 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. 22 * 23 */ 24 25 #ifndef SHARE_VM_GC_SHARED_MODREFBARRIERSET_HPP 26 #define SHARE_VM_GC_SHARED_MODREFBARRIERSET_HPP 27 28 #include "gc/shared/barrierSet.hpp" 29 #include "memory/memRegion.hpp" 30 31 class Klass; 32 33 class ModRefBarrierSet: public BarrierSet { 34 protected: 35 ModRefBarrierSet(BarrierSetAssembler* barrier_set_assembler, 36 BarrierSetC1* barrier_set_c1, 37 BarrierSetC2* barrier_set_c2, 38 const BarrierSet::FakeRtti& fake_rtti) 39 : BarrierSet(barrier_set_assembler, 40 barrier_set_c1, 41 barrier_set_c2, 42 fake_rtti.add_tag(BarrierSet::ModRef)) { } 43 ~ModRefBarrierSet() { } 44 45 public: 46 template <DecoratorSet decorators, typename T> 47 inline void write_ref_field_pre(T* addr) {} 48 49 template <DecoratorSet decorators, typename T> 50 inline void write_ref_field_post(T *addr, oop new_value) {} 51 52 // Causes all refs in "mr" to be assumed to be modified. 53 virtual void invalidate(MemRegion mr) = 0; 54 virtual void write_region(MemRegion mr) = 0; 55 56 // Operations on arrays, or general regions (e.g., for "clone") may be 57 // optimized by some barriers. 58 59 // Below length is the # array elements being written 60 virtual void write_ref_array_pre(oop* dst, size_t length, 61 bool dest_uninitialized = false) {} 62 virtual void write_ref_array_pre(narrowOop* dst, size_t length, 63 bool dest_uninitialized = false) {} 64 // Below count is the # array elements being written, starting 65 // at the address "start", which may not necessarily be HeapWord-aligned 66 inline void write_ref_array(HeapWord* start, size_t count); 67 68 protected: 69 virtual void write_ref_array_work(MemRegion mr) = 0; 70 71 public: 72 // The ModRef abstraction introduces pre and post barriers 73 template <DecoratorSet decorators, typename BarrierSetT> 74 class AccessBarrier: public BarrierSet::AccessBarrier<decorators, BarrierSetT> { 75 typedef BarrierSet::AccessBarrier<decorators, BarrierSetT> Raw; 76 77 public: 78 template <typename T> 79 static void oop_store_in_heap(T* addr, oop value); 80 template <typename T> 81 static oop oop_atomic_cmpxchg_in_heap(oop new_value, T* addr, oop compare_value); 82 template <typename T> 83 static oop oop_atomic_xchg_in_heap(oop new_value, T* addr); 84 85 template <typename T> 86 static bool oop_arraycopy_in_heap(arrayOop src_obj, arrayOop dst_obj, T* src, T* dst, size_t length); 87 88 static void clone_in_heap(oop src, oop dst, size_t size); 89 90 static void oop_store_in_heap_at(oop base, ptrdiff_t offset, oop value) { 91 oop_store_in_heap(AccessInternal::oop_field_addr<decorators>(base, offset), value); 92 } 93 94 static oop oop_atomic_xchg_in_heap_at(oop new_value, oop base, ptrdiff_t offset) { 95 return oop_atomic_xchg_in_heap(new_value, AccessInternal::oop_field_addr<decorators>(base, offset)); 96 } 97 98 static oop oop_atomic_cmpxchg_in_heap_at(oop new_value, oop base, ptrdiff_t offset, oop compare_value) { 99 return oop_atomic_cmpxchg_in_heap(new_value, AccessInternal::oop_field_addr<decorators>(base, offset), compare_value); 100 } 101 }; 102 }; 103 104 template<> 105 struct BarrierSet::GetName<ModRefBarrierSet> { 106 static const BarrierSet::Name value = BarrierSet::ModRef; 107 }; 108 109 #endif // SHARE_VM_GC_SHARED_MODREFBARRIERSET_HPP