1/*
2 * Copyright (c) 2018, 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#include "precompiled.hpp"
26#include "classfile/systemDictionary.hpp"
27#include "classfile/stringTable.hpp"
28#include "gc/shared/oopStorage.hpp"
29#include "oops/access.inline.hpp"
30#include "oops/oop.hpp"
31#include "oops/weakHandle.inline.hpp"
32#include "prims/resolvedMethodTable.hpp"
33#include "utilities/debug.hpp"
34#include "utilities/ostream.hpp"
35
36template <> OopStorage* WeakHandle<vm_class_loader_data>::get_storage() {
37 return SystemDictionary::vm_weak_oop_storage();
38}
39
40template <> OopStorage* WeakHandle<vm_string_table_data>::get_storage() {
41 return StringTable::weak_storage();
42}
43
44template <> OopStorage* WeakHandle<vm_resolved_method_table_data>::get_storage() {
45 return ResolvedMethodTable::weak_storage();
46}
47
48template <WeakHandleType T>
49WeakHandle<T> WeakHandle<T>::create(Handle obj) {
50 assert(obj() != NULL, "no need to create weak null oop");
51 oop* oop_addr = get_storage()->allocate();
52 if (oop_addr == NULL) {
53 vm_exit_out_of_memory(sizeof(oop*), OOM_MALLOC_ERROR, "Unable to create new weak oop handle in OopStorage");
54 }
55 // Create WeakHandle with address returned and store oop into it.
56 NativeAccess<ON_PHANTOM_OOP_REF>::oop_store(oop_addr, obj());
57 return WeakHandle(oop_addr);
58}
59
60template <WeakHandleType T>
61void WeakHandle<T>::release() const {
62 // Only release if the pointer to the object has been created.
63 if (_obj != NULL) {
64 // Clear the WeakHandle. For race in creating ClassLoaderData, we can release this
65 // WeakHandle before it is cleared by GC.
66 NativeAccess<ON_PHANTOM_OOP_REF>::oop_store(_obj, (oop)NULL);
67 get_storage()->release(_obj);
68 }
69}
70
71template <WeakHandleType T>
72void WeakHandle<T>::print() const { print_on(tty); }
73
74template <WeakHandleType T>
75void WeakHandle<T>::print_on(outputStream* st) const {
76 st->print("WeakHandle: " PTR_FORMAT, p2i(peek()));
77}
78
79// Provide instantiation.
80template class WeakHandle<vm_class_loader_data>;
81template class WeakHandle<vm_string_table_data>;
82template class WeakHandle<vm_resolved_method_table_data>;
83