|
0
|
1 /*
|
|
|
2 * Copyright 2005 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
|
|
|
20 * CA 95054 USA or visit www.sun.com if you need additional information or
|
|
|
21 * have any questions.
|
|
|
22 *
|
|
|
23 */
|
|
|
24 #ifdef CHECK_UNHANDLED_OOPS
|
|
|
25
|
|
|
26 // Detect unhanded oops in VM code
|
|
|
27
|
|
|
28 // The design is that when an oop is declared on the stack as a local
|
|
|
29 // variable, the oop is actually a C++ struct with constructor and
|
|
|
30 // destructor. The constructor adds the oop address on a list
|
|
|
31 // off each thread and the destructor removes the oop. At a potential
|
|
|
32 // safepoint, the stack addresses of the local variable oops are trashed
|
|
|
33 // with a recognizeable value. If the local variable is used again, it
|
|
|
34 // will segfault, indicating an unsafe use of that oop.
|
|
|
35 // eg:
|
|
|
36 // oop o; //register &o on list
|
|
|
37 // funct(); // if potential safepoint - causes clear_naked_oops()
|
|
|
38 // // which trashes o above.
|
|
|
39 // o->do_something(); // Crashes because o is unsafe.
|
|
|
40 //
|
|
|
41 // This code implements the details of the unhandled oop list on the thread.
|
|
|
42 //
|
|
|
43
|
|
|
44 class oop;
|
|
|
45 class Thread;
|
|
|
46
|
|
|
47 class UnhandledOopEntry {
|
|
|
48 friend class UnhandledOops;
|
|
|
49 private:
|
|
|
50 oop* _oop_ptr;
|
|
|
51 bool _ok_for_gc;
|
|
|
52 address _pc;
|
|
|
53 public:
|
|
|
54 oop* oop_ptr() { return _oop_ptr; }
|
|
|
55 UnhandledOopEntry() : _oop_ptr(NULL), _ok_for_gc(false), _pc(NULL) {}
|
|
|
56 UnhandledOopEntry(oop* op, address pc) :
|
|
|
57 _oop_ptr(op), _ok_for_gc(false), _pc(pc) {}
|
|
|
58 };
|
|
|
59
|
|
|
60
|
|
|
61 class UnhandledOops {
|
|
|
62 friend class Thread;
|
|
|
63 private:
|
|
|
64 Thread* _thread;
|
|
|
65 int _level;
|
|
|
66 GrowableArray<UnhandledOopEntry> *_oop_list;
|
|
|
67 void allow_unhandled_oop(oop* op);
|
|
|
68 void clear_unhandled_oops();
|
|
|
69 UnhandledOops(Thread* thread);
|
|
|
70 ~UnhandledOops();
|
|
|
71
|
|
|
72 public:
|
|
|
73 static void dump_oops(UnhandledOops* list);
|
|
|
74 void register_unhandled_oop(oop* op, address pc);
|
|
|
75 void unregister_unhandled_oop(oop* op);
|
|
|
76 };
|
|
|
77
|
|
|
78 #ifdef _LP64
|
|
|
79 const intptr_t BAD_OOP_ADDR = 0xfffffffffffffff1;
|
|
|
80 #else
|
|
|
81 const intptr_t BAD_OOP_ADDR = 0xfffffff1;
|
|
|
82 #endif // _LP64
|
|
|
83 #endif // CHECK_UNHANDLED_OOPS
|
