1 /* 2 * Copyright (c) 2001, 2019, 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_GC_SHARED_GENOOPCLOSURES_HPP 26 #define SHARE_GC_SHARED_GENOOPCLOSURES_HPP 27 28 #include "memory/iterator.hpp" 29 #include "oops/oop.hpp" 30 31 class Generation; 32 class CardTableRS; 33 class CardTableBarrierSet; 34 class DefNewGeneration; 35 class KlassRemSet; 36 37 #if INCLUDE_SERIALGC 38 39 // Super closure class for scanning DefNewGeneration. 40 // 41 // - Derived: The derived type provides necessary barrier 42 // after an oop has been updated. 43 template <typename Derived> 44 class FastScanClosure : public BasicOopIterateClosure { 45 private: 46 DefNewGeneration* _young_gen; 47 HeapWord* _young_gen_end; 48 49 template <typename T> 50 void do_oop_work(T* p); 51 52 protected: 53 FastScanClosure(DefNewGeneration* g); 54 55 public: 56 virtual void do_oop(oop* p); 57 virtual void do_oop(narrowOop* p); 58 }; 59 60 // Closure for scanning DefNewGeneration when iterating over the old generation. 61 // 62 // This closure performs barrier store calls on pointers into the DefNewGeneration. 63 class DefNewYoungerGenClosure : public FastScanClosure<DefNewYoungerGenClosure> { 64 private: 65 Generation* _old_gen; 66 HeapWord* _old_gen_start; 67 CardTableRS* _rs; 68 69 public: 70 DefNewYoungerGenClosure(DefNewGeneration* young_gen, Generation* old_gen); 71 72 template <typename T> 73 void barrier(T* p); 74 }; 75 76 // Closure for scanning DefNewGeneration when *not* iterating over the old generation. 77 // 78 // This closures records changes to oops in CLDs. 79 class DefNewScanClosure : public FastScanClosure<DefNewScanClosure> { 80 ClassLoaderData* _scanned_cld; 81 82 public: 83 DefNewScanClosure(DefNewGeneration* g); 84 85 void set_scanned_cld(ClassLoaderData* cld) { 86 assert(cld == NULL || _scanned_cld == NULL, "Must be"); 87 _scanned_cld = cld; 88 } 89 90 template <typename T> 91 void barrier(T* p); 92 }; 93 94 class CLDScanClosure: public CLDClosure { 95 DefNewScanClosure* _scavenge_closure; 96 // true if the the modified oops state should be saved. 97 bool _accumulate_modified_oops; 98 public: 99 CLDScanClosure(DefNewScanClosure* scavenge_closure, 100 bool accumulate_modified_oops) : 101 _scavenge_closure(scavenge_closure), _accumulate_modified_oops(accumulate_modified_oops) {} 102 void do_cld(ClassLoaderData* cld); 103 }; 104 105 #endif // INCLUDE_SERIALGC 106 107 class FilteringClosure: public OopIterateClosure { 108 private: 109 HeapWord* _boundary; 110 OopIterateClosure* _cl; 111 protected: 112 template <class T> inline void do_oop_work(T* p); 113 public: 114 FilteringClosure(HeapWord* boundary, OopIterateClosure* cl) : 115 OopIterateClosure(cl->ref_discoverer()), _boundary(boundary), 116 _cl(cl) {} 117 virtual void do_oop(oop* p); 118 virtual void do_oop(narrowOop* p); 119 virtual bool do_metadata() { assert(!_cl->do_metadata(), "assumption broken, must change to 'return _cl->do_metadata()'"); return false; } 120 virtual void do_klass(Klass*) { ShouldNotReachHere(); } 121 virtual void do_cld(ClassLoaderData*) { ShouldNotReachHere(); } 122 }; 123 124 #if INCLUDE_SERIALGC 125 126 // Closure for scanning DefNewGeneration's weak references. 127 // -- weak references are processed all at once, 128 // with no notion of which generation they were in. 129 class ScanWeakRefClosure: public OopClosure { 130 protected: 131 DefNewGeneration* _g; 132 HeapWord* _boundary; 133 template <class T> inline void do_oop_work(T* p); 134 public: 135 ScanWeakRefClosure(DefNewGeneration* g); 136 virtual void do_oop(oop* p); 137 virtual void do_oop(narrowOop* p); 138 }; 139 140 #endif // INCLUDE_SERIALGC 141 142 #endif // SHARE_GC_SHARED_GENOOPCLOSURES_HPP