Instruction11n.java revision 16a911620ccf7b530b873fb71cf13e8dcb88ad28 
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.SingleRegisterInstruction;
34import org.jf.dexlib.Code.LiteralInstruction;
35import org.jf.dexlib.DexFile;
36import org.jf.dexlib.Util.NumberUtils;
37import org.jf.dexlib.Util.AnnotatedOutput;
38
39public class Instruction11n extends Instruction implements SingleRegisterInstruction, LiteralInstruction {
40    public static final InstructionFactory Factory = new Factory();
41    private byte regA;
42    private byte litB;
43
44    public Instruction11n(Opcode opcode, byte regA, byte litB) {
45        super(opcode);
46
47        if (regA >= 1 << 4) {
48            throw new RuntimeException("The register number must be less than v16");
49        }
50
51        if (litB < -(1 << 3) ||
52                litB >= 1 << 3) {
53            throw new RuntimeException("The literal value must be between -8 and 7 inclusive");
54        }
55
56        this.regA = regA;
57        this.litB = litB;
58    }
59
60    private Instruction11n(Opcode opcode, byte[] buffer, int bufferIndex) {
61        super(opcode);
62
63        this.regA = NumberUtils.decodeLowUnsignedNibble(buffer[bufferIndex + 1]);
64        this.litB = NumberUtils.decodeHighSignedNibble(buffer[bufferIndex + 1]);
65    }
66
67    public void writeInstruction(AnnotatedOutput out, int currentCodeAddress) {
68        out.writeByte(opcode.value);
69        out.writeByte((litB << 4) | regA);
70    }
71
72    public Format getFormat() {
73        return Format.Format11n;
74    }
75
76    public int getRegisterA() {
77        return regA;
78    }
79
80    public long getLiteral() {
81        return litB;
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 Instruction11n(opcode, buffer, bufferIndex);
87        }
88    }
89}