Instruction22s.java revision 5867263eb588f4671400895d1e6b01c01535061b 
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.TwoRegisterInstruction;
34import org.jf.dexlib.DexFile;
35import org.jf.dexlib.Util.NumberUtils;
36import org.jf.dexlib.Util.Output;
37
38public class Instruction22s extends Instruction implements TwoRegisterInstruction {
39    public static final Instruction.InstructionFactory Factory = new Factory();
40
41    public static void emit(Output out, Opcode opcode, byte regA, byte regB, short litC) {
42        if (regA >= 1 << 4 ||
43                regB >= 1 << 4) {
44            throw new RuntimeException("The register number must be less than v16");
45        }
46
47        out.writeByte(opcode.value);
48        out.writeByte((regB << 4) | regA);
49        out.writeShort(litC);
50    }
51
52    private Instruction22s(Opcode opcode, byte[] buffer, int bufferIndex) {
53        super(opcode, buffer, bufferIndex);
54    }
55
56    public Format getFormat() {
57        return Format.Format22s;
58    }
59
60    public int getRegisterA() {
61        return NumberUtils.decodeLowUnsignedNibble(buffer[bufferIndex + 1]);
62    }
63
64    public int getRegisterB() {
65        return NumberUtils.decodeHighUnsignedNibble(buffer[bufferIndex + 1]);
66    }
67
68    public short getLiteral() {
69        return NumberUtils.decodeShort(buffer, bufferIndex + 2);
70    }
71
72    private static class Factory implements Instruction.InstructionFactory {
73        public Instruction makeInstruction(DexFile dexFile, Opcode opcode, byte[] buffer, int bufferIndex) {
74            return new Instruction22s(opcode, buffer, bufferIndex);
75        }
76    }
77}
78