Instruction31t.java revision 526d617e05d512318f1e9f9be7de3a3c2a4f80be 
1/*
2 * [The "BSD licence"]
3 * Copyright (c) 2009 Ben Gruver
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. The name of the author may not be used to endorse or promote products
15 *    derived from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29package org.jf.dexlib.Code.Format;
30
31import org.jf.dexlib.Code.Instruction;
32import org.jf.dexlib.Code.Opcode;
33import org.jf.dexlib.Code.OffsetInstruction;
34import org.jf.dexlib.Code.SingleRegisterInstruction;
35import org.jf.dexlib.DexFile;
36import org.jf.dexlib.Util.NumberUtils;
37import org.jf.dexlib.Util.AnnotatedOutput;
38
39public class Instruction31t extends Instruction implements OffsetInstruction, SingleRegisterInstruction {
40    public static final Instruction.InstructionFactory Factory = new Factory();
41    private byte regA;
42    private int offset;
43
44    public Instruction31t(Opcode opcode, short regA, int offB) {
45        super(opcode);
46
47        if (regA >= 1 << 8) {
48            throw new RuntimeException("The register number must be less than v256");
49        }
50
51        this.regA = (byte)regA;
52        this.offset = offB;
53    }
54
55    private Instruction31t(Opcode opcode, byte[] buffer, int bufferIndex) {
56        super(opcode);
57
58        this.regA = buffer[bufferIndex + 1];
59        this.offset = NumberUtils.decodeInt(buffer, bufferIndex + 2);
60    }
61
62    protected void writeInstruction(AnnotatedOutput out, int currentCodeOffset) {
63        out.writeByte(opcode.value);
64        out.writeByte(regA);
65        out.writeInt(offset + (((currentCodeOffset/2) + offset) % 2));
66    }
67
68    public void updateOffset(int offset) {
69        this.offset = offset;
70    }
71
72    public Format getFormat() {
73        return Format.Format31t;
74    }
75
76    public int getRegisterA() {
77        return regA & 0xFF;
78    }
79
80    public int getOffset() {
81        return offset;
82    }
83
84    private static class Factory implements Instruction.InstructionFactory {
85        public Instruction makeInstruction(DexFile dexFile, Opcode opcode, byte[] buffer, int bufferIndex) {
86            return new Instruction31t(opcode, buffer, bufferIndex);
87        }
88    }
89}
90