1/***
2 * ASM: a very small and fast Java bytecode manipulation framework
3 * Copyright (c) 2000-2007 INRIA, France Telecom
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 * 3. Neither the name of the copyright holders nor the names of its
15 *    contributors may be used to endorse or promote products derived from
16 *    this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
19 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
22 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
28 * THE POSSIBILITY OF SUCH DAMAGE.
29 */
30package org.mockito.asm.tree.analysis;
31
32import java.util.ArrayList;
33import java.util.List;
34
35import org.mockito.asm.tree.JumpInsnNode;
36import org.mockito.asm.tree.LabelNode;
37
38/**
39 * A method subroutine (corresponds to a JSR instruction).
40 *
41 * @author Eric Bruneton
42 */
43class Subroutine {
44
45    LabelNode start;
46
47    boolean[] access;
48
49    List callers;
50
51    private Subroutine() {
52    }
53
54    Subroutine(
55        final LabelNode start,
56        final int maxLocals,
57        final JumpInsnNode caller)
58    {
59        this.start = start;
60        this.access = new boolean[maxLocals];
61        this.callers = new ArrayList();
62        callers.add(caller);
63    }
64
65    public Subroutine copy() {
66        Subroutine result = new Subroutine();
67        result.start = start;
68        result.access = new boolean[access.length];
69        System.arraycopy(access, 0, result.access, 0, access.length);
70        result.callers = new ArrayList(callers);
71        return result;
72    }
73
74    public boolean merge(final Subroutine subroutine) throws AnalyzerException {
75        boolean changes = false;
76        for (int i = 0; i < access.length; ++i) {
77            if (subroutine.access[i] && !access[i]) {
78                access[i] = true;
79                changes = true;
80            }
81        }
82        if (subroutine.start == start) {
83            for (int i = 0; i < subroutine.callers.size(); ++i) {
84                Object caller = subroutine.callers.get(i);
85                if (!callers.contains(caller)) {
86                    callers.add(caller);
87                    changes = true;
88                }
89            }
90        }
91        return changes;
92    }
93}