1 /* 2 * Copyright (c) 2020, 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_OBJECTMARKER_HPP 26 #define SHARE_GC_SHARED_OBJECTMARKER_HPP 27 28 #include "memory/allocation.hpp" 29 #include "utilities/growableArray.hpp" 30 31 // ObjectMarker is used to support JVMTI for marking objects when walking the 32 // heap. 33 class ObjectMarker : public CHeapObj<mtInternal> { 34 protected: 35 bool _needs_reset; 36 public: 37 // initialize 38 virtual bool init() = 0; 39 // clean-up 40 virtual void done() = 0; 41 42 // mark an object if not yet marked. 43 // return true if the oop is marked by this call 44 virtual bool mark(oop o) = 0; 45 // check if the object has been 46 virtual bool marked(oop o) = 0; 47 48 bool needs_reset() const { return _needs_reset; } 49 void set_needs_reset(bool v) { _needs_reset = v; } 50 }; 51 52 // Default implementation 53 class DefaultObjectMarker : public ObjectMarker { 54 private: 55 // saved headers 56 GrowableArray<oop>* _saved_oop_stack; 57 GrowableArray<markWord>* _saved_mark_stack; 58 59 public: 60 DefaultObjectMarker(); 61 bool init(); 62 void done(); 63 64 bool mark(oop o); 65 bool marked(oop o); 66 }; 67 68 #endif // SHARE_GC_SHARED_OBJECTMARKER_HPP