| 1 | /* |
| 2 | * Copyright (c) 2017, 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_OOPS_OOPHANDLE_HPP |
| 26 | #define SHARE_OOPS_OOPHANDLE_HPP |
| 27 | |
| 28 | #include "oops/oop.hpp" |
| 29 | |
| 30 | // Simple class for encapsulating oop pointers stored in metadata. |
| 31 | // These are different from Handle. The Handle class stores pointers |
| 32 | // to oops on the stack, and manages the allocation from a thread local |
| 33 | // area in the constructor. |
| 34 | // This assumes that the caller will allocate the handle in the appropriate |
| 35 | // area. The reason for the encapsulation is to help with naming and to allow |
| 36 | // future uses for read barriers. |
| 37 | |
| 38 | class OopHandle { |
| 39 | friend class VMStructs; |
| 40 | private: |
| 41 | oop* _obj; |
| 42 | |
| 43 | public: |
| 44 | OopHandle() : _obj(NULL) {} |
| 45 | OopHandle(oop* w) : _obj(w) {} |
| 46 | |
| 47 | inline oop resolve() const; |
| 48 | inline oop peek() const; |
| 49 | |
| 50 | // Used only for removing handle. |
| 51 | oop* ptr_raw() const { return _obj; } |
| 52 | }; |
| 53 | |
| 54 | #endif // SHARE_OOPS_OOPHANDLE_HPP |
| 55 | |