1 /*
2 * Copyright (c) 2000, 2005, 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 class BciMap;
26
27 // methodComparator provides an interface for determining if methods of
28 // different versions of classes are equivalent or switchable
29
30 class MethodComparator {
31 private:
32 static BytecodeStream *_s_old, *_s_new;
33 static constantPoolOop _old_cp, _new_cp;
34 static BciMap *_bci_map;
35 static bool _switchable_test;
36 static GrowableArray<int> *_fwd_jmps;
37
38 static bool args_same(Bytecodes::Code c_old, Bytecodes::Code c_new);
39 static int check_stack_and_locals_size(methodOop old_method, methodOop new_method);
40
41 public:
42 // Check if the new method is equivalent to the old one modulo constant pool (EMCP).
43 // Intuitive definition: two versions of the same method are EMCP, if they don't differ
44 // on the source code level. Practically, we check whether the only difference between
103 }
104
105 int new_bci_for_old(int old_bci) {
106 if (_cur_pos == 0 || old_bci < _old_bci[0]) return old_bci;
107 _pos = 1;
108 while (_pos < _cur_pos && old_bci >= _old_bci[_pos])
109 _pos++;
110 return _new_end_bci[_pos-1] + (old_bci - _old_bci[_pos-1]);
111 }
112
113 // Test if two indexes - one in the old method and another in the new one - correspond
114 // to the same bytecode
115 bool old_and_new_locations_same(int old_dest_bci, int new_dest_bci) {
116 if (new_bci_for_old(old_dest_bci) == new_dest_bci)
117 return true;
118 else if (_old_bci[_pos-1] == old_dest_bci)
119 return (new_dest_bci == _new_st_bci[_pos-1]);
120 else return false;
121 }
122 };
|
1 /*
2 * Copyright (c) 2000, 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_PRIMS_METHODCOMPARATOR_HPP
26 #define SHARE_VM_PRIMS_METHODCOMPARATOR_HPP
27
28 #include "interpreter/bytecodeStream.hpp"
29 #include "oops/constantPoolOop.hpp"
30 #include "oops/methodOop.hpp"
31
32 class BciMap;
33
34 // methodComparator provides an interface for determining if methods of
35 // different versions of classes are equivalent or switchable
36
37 class MethodComparator {
38 private:
39 static BytecodeStream *_s_old, *_s_new;
40 static constantPoolOop _old_cp, _new_cp;
41 static BciMap *_bci_map;
42 static bool _switchable_test;
43 static GrowableArray<int> *_fwd_jmps;
44
45 static bool args_same(Bytecodes::Code c_old, Bytecodes::Code c_new);
46 static int check_stack_and_locals_size(methodOop old_method, methodOop new_method);
47
48 public:
49 // Check if the new method is equivalent to the old one modulo constant pool (EMCP).
50 // Intuitive definition: two versions of the same method are EMCP, if they don't differ
51 // on the source code level. Practically, we check whether the only difference between
110 }
111
112 int new_bci_for_old(int old_bci) {
113 if (_cur_pos == 0 || old_bci < _old_bci[0]) return old_bci;
114 _pos = 1;
115 while (_pos < _cur_pos && old_bci >= _old_bci[_pos])
116 _pos++;
117 return _new_end_bci[_pos-1] + (old_bci - _old_bci[_pos-1]);
118 }
119
120 // Test if two indexes - one in the old method and another in the new one - correspond
121 // to the same bytecode
122 bool old_and_new_locations_same(int old_dest_bci, int new_dest_bci) {
123 if (new_bci_for_old(old_dest_bci) == new_dest_bci)
124 return true;
125 else if (_old_bci[_pos-1] == old_dest_bci)
126 return (new_dest_bci == _new_st_bci[_pos-1]);
127 else return false;
128 }
129 };
130
131 #endif // SHARE_VM_PRIMS_METHODCOMPARATOR_HPP
|