Instruction22cs.java revision 6325930f675aa264fd3d6d1fb48dfa390da3261d 
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.Util.NumberUtils;
35import org.jf.dexlib.Util.AnnotatedOutput;
36import org.jf.dexlib.DexFile;
37
38public class Instruction22cs extends Instruction implements TwoRegisterInstruction {
39    public static final Instruction.InstructionFactory Factory = new Factory();
40    private byte regA;
41    private byte regB;
42    private short fieldOffset;
43
44    public Instruction22cs(Opcode opcode, byte regA, byte regB, int fieldOffset) {
45        super(opcode);
46
47        if (regA >= 1 << 4 ||
48                regB >= 1 << 4) {
49            throw new RuntimeException("The register number must be less than v16");
50        }
51
52        if (fieldOffset >= 1 << 16) {
53            throw new RuntimeException("The field offset must be less than 65536");
54        }
55
56        this.regA = regA;
57        this.regB = regB;
58        this.fieldOffset = (short)fieldOffset;
59    }
60
61    private Instruction22cs(Opcode opcode, byte[] buffer, int bufferIndex) {
62        super(opcode);
63
64        this.regA = NumberUtils.decodeLowUnsignedNibble(buffer[bufferIndex + 1]);
65        this.regB = NumberUtils.decodeHighUnsignedNibble(buffer[bufferIndex + 1]);
66        this.fieldOffset = (short)NumberUtils.decodeUnsignedShort(buffer, bufferIndex + 2);
67    }
68
69    protected void writeInstruction(AnnotatedOutput out, int currentCodeOffset) {
70        out.writeByte(opcode.value);
71        out.writeByte((regB << 4) | regA);
72        out.writeShort(fieldOffset);
73    }
74
75    public Format getFormat() {
76        return Format.Format22cs;
77    }
78
79    public int getRegisterA() {
80        return regA;
81    }
82
83    public int getRegisterB() {
84        return regB;
85    }
86
87    public int getFieldOffset() {
88        return fieldOffset & 0xFFFF;
89    }
90
91    private static class Factory implements Instruction.InstructionFactory {
92        public Instruction makeInstruction(DexFile dexFile, Opcode opcode, byte[] buffer, int bufferIndex) {
93            return new Instruction22cs(opcode, buffer, bufferIndex);
94        }
95    }
96}
97