1 /* 2 * Copyright (c) 2016, 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_INLINE_HPP 26 #define SHARE_VM_GC_SHARED_MODREFBARRIERSET_INLINE_HPP 27 28 #include "gc/shared/modRefBarrierSet.hpp" 29 #include "oops/oop.hpp" 30 31 // count is number of array elements being written 32 void ModRefBarrierSet::write_ref_array(HeapWord* start, size_t count) { 33 assert(count <= (size_t)max_intx, "count too large"); 34 HeapWord* end = (HeapWord*)((char*)start + (count*heapOopSize)); 35 // In the case of compressed oops, start and end may potentially be misaligned; 36 // so we need to conservatively align the first downward (this is not 37 // strictly necessary for current uses, but a case of good hygiene and, 38 // if you will, aesthetics) and the second upward (this is essential for 39 // current uses) to a HeapWord boundary, so we mark all cards overlapping 40 // this write. If this evolves in the future to calling a 41 // logging barrier of narrow oop granularity, like the pre-barrier for G1 42 // (mentioned here merely by way of example), we will need to change this 43 // interface, so it is "exactly precise" (if i may be allowed the adverbial 44 // redundancy for emphasis) and does not include narrow oop slots not 45 // included in the original write interval. 46 HeapWord* aligned_start = (HeapWord*)align_size_down((uintptr_t)start, HeapWordSize); 47 HeapWord* aligned_end = (HeapWord*)align_size_up ((uintptr_t)end, HeapWordSize); 48 // If compressed oops were not being used, these should already be aligned 49 assert(UseCompressedOops || (aligned_start == start && aligned_end == end), 50 "Expected heap word alignment of start and end"); 51 write_ref_array_region(MemRegion(aligned_start, aligned_end)); 52 } 53 54 template <DecoratorSet decorators, typename BarrierSetT> 55 inline void ModRefBarrierSet::AccessBarrier<decorators, BarrierSetT>:: 56 oop_store(void* addr, oop value) { 57 if (!DecoratorTest<decorators>::HAS_ACCESS_ON_HEAP || DecoratorTest<decorators>::HAS_ACCESS_WEAK) { 58 Basic::oop_store(addr, value); 59 } else { 60 BarrierSetT *bs = barrier_set_cast<BarrierSetT>(barrier_set()); 61 bs->BarrierSetT::template write_ref_field_pre<decorators>(addr); 62 Basic::oop_store(addr, value); 63 bs->BarrierSetT::template write_ref_field_post<decorators>(addr, value); 64 } 65 } 66 67 template <DecoratorSet decorators, typename BarrierSetT> 68 inline void ModRefBarrierSet::AccessBarrier<decorators, BarrierSetT>:: 69 oop_store_at(Klass* base, ptrdiff_t offset, oop value) { 70 BarrierSetT *bs = barrier_set_cast<BarrierSetT>(barrier_set()); 71 bs->BarrierSetT::klass_update_barrier_set_pre(base, (oop*)Basic::field_addr(base, offset)); 72 Basic::oop_store(Basic::field_addr(base, offset), value); 73 bs->BarrierSetT::klass_update_barrier_set(base, (oop*)Basic::field_addr(base, offset), value); 74 } 75 76 template <DecoratorSet decorators, typename BarrierSetT> 77 inline oop ModRefBarrierSet::AccessBarrier<decorators, BarrierSetT>:: 78 oop_cas(oop new_value, void* addr, oop compare_value) { 79 if (!DecoratorTest<decorators>::HAS_ACCESS_ON_HEAP || DecoratorTest<decorators>::HAS_ACCESS_WEAK) { 80 return Basic::oop_cas(new_value, addr, compare_value); 81 } else { 82 BarrierSetT *bs = barrier_set_cast<BarrierSetT>(barrier_set()); 83 bs->BarrierSetT::template write_ref_field_pre<decorators>(addr); 84 oop result = Basic::oop_cas(new_value, addr, compare_value); 85 if (result == compare_value) { 86 bs->BarrierSetT::template write_ref_field_post<decorators>(addr, new_value); 87 } 88 return result; 89 } 90 } 91 92 template <DecoratorSet decorators, typename BarrierSetT> 93 inline oop ModRefBarrierSet::AccessBarrier<decorators, BarrierSetT>::oop_swap(oop new_value, void* addr) { 94 if (!DecoratorTest<decorators>::HAS_ACCESS_ON_HEAP || DecoratorTest<decorators>::HAS_ACCESS_WEAK) { 95 return Basic::oop_swap(new_value, addr); 96 } else { 97 BarrierSetT *bs = barrier_set_cast<BarrierSetT>(barrier_set()); 98 bs->BarrierSetT::template write_ref_field_pre<decorators>(addr); 99 oop result = Basic::oop_swap(new_value, addr); 100 bs->BarrierSetT::template write_ref_field_post<decorators>(addr, new_value); 101 return result; 102 } 103 } 104 105 template <DecoratorSet decorators, typename BarrierSetT> 106 template <typename T> 107 inline bool ModRefBarrierSet::AccessBarrier<decorators, BarrierSetT>:: 108 oop_copy(arrayOop src_obj, arrayOop dst_obj, T* src, T* dst, size_t length) { 109 BarrierSetT *bs = barrier_set_cast<BarrierSetT>(barrier_set()); 110 111 if (DecoratorTest<decorators>::HAS_DEST_COVARIANT) { 112 // Optimized case 113 bs->BarrierSetT::write_ref_array_pre(dst, (int)length, 114 DecoratorTest<decorators>::HAS_DEST_NOT_INITIALIZED); 115 Basic::template oop_copy<T>(src_obj, dst_obj, src, dst, length); 116 bs->BarrierSetT::write_ref_array((HeapWord*)dst, length); 117 } else { 118 Klass* bound = bound_for_array((oop)dst_obj); 119 T* from = src; 120 T* end = from + length; 121 for (T* p = dst; from < end; from++, p++) { 122 // XXX this is going to be slow. 123 T element = *from; 124 // even slower now 125 bool element_is_null = oopDesc::is_null(element); 126 oop new_val = element_is_null ? oop(NULL) 127 : oopDesc::decode_heap_oop_not_null(element); 128 if (element_is_null || is_bounded_by(new_val, bound)) { 129 bs->BarrierSetT::template write_ref_field_pre<decorators>((void*)p); 130 *p = element; 131 } else { 132 // We must do a barrier to cover the partial copy. 133 const size_t pd = pointer_delta(p, dst, (size_t)heapOopSize); 134 // pointer delta is scaled to number of elements (length field in 135 // objArrayOop) which we assume is 32 bit. 136 assert(pd == (size_t)(int)pd, "length field overflow"); 137 bs->BarrierSetT::write_ref_array((HeapWord*)dst, pd); 138 return false; 139 } 140 } 141 bs->BarrierSetT::write_ref_array((HeapWord*)dst, length); 142 } 143 return true; 144 } 145 146 template <DecoratorSet decorators, typename BarrierSetT> 147 inline void ModRefBarrierSet::AccessBarrier<decorators, BarrierSetT>:: 148 clone(oop src, oop dst, size_t size) { 149 Basic::clone(src, dst, size); 150 BarrierSetT *bs = barrier_set_cast<BarrierSetT>(barrier_set()); 151 bs->BarrierSetT::write_region(MemRegion((HeapWord*)(void*)dst, size)); 152 } 153 154 #endif // SHARE_VM_GC_SHARED_MODREFBARRIERSET_INLINE_HPP