|
1 /* |
|
2 * Copyright (c) 1998, 2010, 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_VM_RUNTIME_BASICLOCK_HPP |
|
26 #define SHARE_VM_RUNTIME_BASICLOCK_HPP |
|
27 |
|
28 #include "oops/markOop.hpp" |
|
29 #include "runtime/handles.hpp" |
|
30 #include "utilities/top.hpp" |
|
31 |
|
32 class BasicLock VALUE_OBJ_CLASS_SPEC { |
|
33 friend class VMStructs; |
|
34 private: |
|
35 volatile markOop _displaced_header; |
|
36 public: |
|
37 markOop displaced_header() const { return _displaced_header; } |
|
38 void set_displaced_header(markOop header) { _displaced_header = header; } |
|
39 |
|
40 void print_on(outputStream* st) const; |
|
41 |
|
42 // move a basic lock (used during deoptimization |
|
43 void move_to(oop obj, BasicLock* dest); |
|
44 |
|
45 static int displaced_header_offset_in_bytes() { return offset_of(BasicLock, _displaced_header); } |
|
46 }; |
|
47 |
|
48 // A BasicObjectLock associates a specific Java object with a BasicLock. |
|
49 // It is currently embedded in an interpreter frame. |
|
50 |
|
51 // Because some machines have alignment restrictions on the control stack, |
|
52 // the actual space allocated by the interpreter may include padding words |
|
53 // after the end of the BasicObjectLock. Also, in order to guarantee |
|
54 // alignment of the embedded BasicLock objects on such machines, we |
|
55 // put the embedded BasicLock at the beginning of the struct. |
|
56 |
|
57 class BasicObjectLock VALUE_OBJ_CLASS_SPEC { |
|
58 friend class VMStructs; |
|
59 private: |
|
60 BasicLock _lock; // the lock, must be double word aligned |
|
61 oop _obj; // object holds the lock; |
|
62 |
|
63 public: |
|
64 // Manipulation |
|
65 oop obj() const { return _obj; } |
|
66 void set_obj(oop obj) { _obj = obj; } |
|
67 BasicLock* lock() { return &_lock; } |
|
68 |
|
69 // Note: Use frame::interpreter_frame_monitor_size() for the size of BasicObjectLocks |
|
70 // in interpreter activation frames since it includes machine-specific padding. |
|
71 static int size() { return sizeof(BasicObjectLock)/wordSize; } |
|
72 |
|
73 // GC support |
|
74 void oops_do(OopClosure* f) { f->do_oop(&_obj); } |
|
75 |
|
76 static int obj_offset_in_bytes() { return offset_of(BasicObjectLock, _obj); } |
|
77 static int lock_offset_in_bytes() { return offset_of(BasicObjectLock, _lock); } |
|
78 }; |
|
79 |
|
80 |
|
81 #endif // SHARE_VM_RUNTIME_BASICLOCK_HPP |