Instruction22s.java revision 83b80f81d311b233188c281059aad4a9f5e8b4e6 
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.DexFile;
34import org.jf.dexlib.Util.NumberUtils;
35
36public class Instruction22s extends Instruction {
37    public static final Instruction.InstructionFactory Factory = new Factory();
38
39    public Instruction22s(Opcode opcode, byte regA, byte regB, short litC) {
40        super(opcode);
41
42        if (regA >= 1 << 4 ||
43                regB >= 1 << 4) {
44            throw new RuntimeException("The register number must be less than v16");
45        }
46
47        buffer[0] = opcode.value;
48        buffer[1] = (byte) ((regB << 4) | regA);
49        buffer[2] = (byte) litC;
50        buffer[3] = (byte) (litC >> 8);
51    }
52
53    private Instruction22s(Opcode opcode, byte[] buffer, int bufferIndex) {
54        super(opcode, buffer, bufferIndex);
55    }
56
57    public Format getFormat() {
58        return Format.Format22s;
59    }
60
61    public byte getRegisterA() {
62        return NumberUtils.decodeLowUnsignedNibble(buffer[bufferIndex + 1]);
63    }
64
65    public byte getRegisterB() {
66        return NumberUtils.decodeHighUnsignedNibble(buffer[bufferIndex + 1]);
67    }
68
69    public short getLiteral() {
70        return NumberUtils.decodeShort(buffer, bufferIndex + 2);
71    }
72
73    private static class Factory implements Instruction.InstructionFactory {
74        public Instruction makeInstruction(DexFile dexFile, Opcode opcode, byte[] buffer, int bufferIndex) {
75            return new Instruction22s(opcode, buffer, bufferIndex);
76        }
77    }
78}
79