1 /* 2 * Copyright (c) 2001, 2010, 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_MEMORY_GENOOPCLOSURES_INLINE_HPP 26 #define SHARE_VM_MEMORY_GENOOPCLOSURES_INLINE_HPP 27 28 #include "memory/cardTableRS.hpp" 29 #include "memory/defNewGeneration.hpp" 30 #include "memory/genCollectedHeap.hpp" 31 #include "memory/genOopClosures.hpp" 32 #include "memory/genRemSet.hpp" 33 #include "memory/generation.hpp" 34 #include "memory/sharedHeap.hpp" 35 #include "memory/space.hpp" 36 37 inline OopsInGenClosure::OopsInGenClosure(Generation* gen) : 38 OopClosure(gen->ref_processor()), _orig_gen(gen), _rs(NULL) { 39 set_generation(gen); 40 } 41 42 inline void OopsInGenClosure::set_generation(Generation* gen) { 43 _gen = gen; 44 _gen_boundary = _gen->reserved().start(); 45 // Barrier set for the heap, must be set after heap is initialized 46 if (_rs == NULL) { 47 GenRemSet* rs = SharedHeap::heap()->rem_set(); 48 assert(rs->rs_kind() == GenRemSet::CardTable, "Wrong rem set kind"); 49 _rs = (CardTableRS*)rs; 50 } 51 } 52 53 template <class T> inline void OopsInGenClosure::do_barrier(T* p) { 54 assert(generation()->is_in_reserved(p), "expected ref in generation"); 55 T heap_oop = oopDesc::load_heap_oop(p); 56 assert(!oopDesc::is_null(heap_oop), "expected non-null oop"); 57 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop); 58 // If p points to a younger generation, mark the card. 59 if ((HeapWord*)obj < _gen_boundary) { 60 _rs->inline_write_ref_field_gc(p, obj); 61 } 62 } 63 64 template <class T> inline void OopsInGenClosure::par_do_barrier(T* p) { 65 assert(generation()->is_in_reserved(p), "expected ref in generation"); 66 T heap_oop = oopDesc::load_heap_oop(p); 67 assert(!oopDesc::is_null(heap_oop), "expected non-null oop"); 68 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop); 69 // If p points to a younger generation, mark the card. 70 if ((HeapWord*)obj < gen_boundary()) { 71 rs()->write_ref_field_gc_par(p, obj); 72 } 73 } 74 75 // NOTE! Any changes made here should also be made 76 // in FastScanClosure::do_oop_work() 77 template <class T> inline void ScanClosure::do_oop_work(T* p) { 78 T heap_oop = oopDesc::load_heap_oop(p); 79 // Should we copy the obj? 80 if (!oopDesc::is_null(heap_oop)) { 81 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop); 82 if ((HeapWord*)obj < _boundary) { 83 assert(!_g->to()->is_in_reserved(obj), "Scanning field twice?"); 84 oop new_obj = obj->is_forwarded() ? obj->forwardee() 85 : _g->copy_to_survivor_space(obj); 86 oopDesc::encode_store_heap_oop_not_null(p, new_obj); 87 } 88 if (_gc_barrier) { 89 // Now call parent closure 90 do_barrier(p); 91 } 92 } 93 } 94 95 inline void ScanClosure::do_oop_nv(oop* p) { ScanClosure::do_oop_work(p); } 96 inline void ScanClosure::do_oop_nv(narrowOop* p) { ScanClosure::do_oop_work(p); } 97 98 // NOTE! Any changes made here should also be made 99 // in ScanClosure::do_oop_work() 100 template <class T> inline void FastScanClosure::do_oop_work(T* p) { 101 T heap_oop = oopDesc::load_heap_oop(p); 102 // Should we copy the obj? 103 if (!oopDesc::is_null(heap_oop)) { 104 oop obj = oopDesc::decode_heap_oop_not_null(heap_oop); 105 if ((HeapWord*)obj < _boundary) { 106 assert(!_g->to()->is_in_reserved(obj), "Scanning field twice?"); 107 oop new_obj = obj->is_forwarded() ? obj->forwardee() 108 : _g->copy_to_survivor_space(obj); 109 oopDesc::encode_store_heap_oop_not_null(p, new_obj); 110 if (_gc_barrier) { 111 // Now call parent closure 112 do_barrier(p); 113 } 114 } 115 } 116 } 117 118 inline void FastScanClosure::do_oop_nv(oop* p) { FastScanClosure::do_oop_work(p); } 119 inline void FastScanClosure::do_oop_nv(narrowOop* p) { FastScanClosure::do_oop_work(p); } 120 121 // Note similarity to ScanClosure; the difference is that 122 // the barrier set is taken care of outside this closure. 123 template <class T> inline void ScanWeakRefClosure::do_oop_work(T* p) { 124 assert(!oopDesc::is_null(*p), "null weak reference?"); 125 oop obj = oopDesc::load_decode_heap_oop_not_null(p); 126 // weak references are sometimes scanned twice; must check 127 // that to-space doesn't already contain this object 128 if ((HeapWord*)obj < _boundary && !_g->to()->is_in_reserved(obj)) { 129 oop new_obj = obj->is_forwarded() ? obj->forwardee() 130 : _g->copy_to_survivor_space(obj); 131 oopDesc::encode_store_heap_oop_not_null(p, new_obj); 132 } 133 } 134 135 inline void ScanWeakRefClosure::do_oop_nv(oop* p) { ScanWeakRefClosure::do_oop_work(p); } 136 inline void ScanWeakRefClosure::do_oop_nv(narrowOop* p) { ScanWeakRefClosure::do_oop_work(p); } 137 138 #endif // SHARE_VM_MEMORY_GENOOPCLOSURES_INLINE_HPP