1/*
2 * Copyright (C) 2007 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package com.android.dx.dex.code.form;
18
19import com.android.dx.dex.code.DalvInsn;
20import com.android.dx.dex.code.InsnFormat;
21import com.android.dx.dex.code.SimpleInsn;
22import com.android.dx.rop.code.RegisterSpecList;
23import com.android.dx.util.AnnotatedOutput;
24
25import java.util.BitSet;
26
27/**
28 * Instruction format {@code 23x}. See the instruction format spec
29 * for details.
30 */
31public final class Form23x extends InsnFormat {
32    /** {@code non-null;} unique instance of this class */
33    public static final InsnFormat THE_ONE = new Form23x();
34
35    /**
36     * Constructs an instance. This class is not publicly
37     * instantiable. Use {@link #THE_ONE}.
38     */
39    private Form23x() {
40        // This space intentionally left blank.
41    }
42
43    /** {@inheritDoc} */
44    @Override
45    public String insnArgString(DalvInsn insn) {
46        RegisterSpecList regs = insn.getRegisters();
47        return regs.get(0).regString() + ", " + regs.get(1).regString() +
48            ", " + regs.get(2).regString();
49    }
50
51    /** {@inheritDoc} */
52    @Override
53    public String insnCommentString(DalvInsn insn, boolean noteIndices) {
54        // This format has no comment.
55        return "";
56    }
57
58    /** {@inheritDoc} */
59    @Override
60    public int codeSize() {
61        return 2;
62    }
63
64    /** {@inheritDoc} */
65    @Override
66    public boolean isCompatible(DalvInsn insn) {
67        RegisterSpecList regs = insn.getRegisters();
68
69        return (insn instanceof SimpleInsn) &&
70            (regs.size() == 3) &&
71            unsignedFitsInByte(regs.get(0).getReg()) &&
72            unsignedFitsInByte(regs.get(1).getReg()) &&
73            unsignedFitsInByte(regs.get(2).getReg());
74    }
75
76    /** {@inheritDoc} */
77    @Override
78    public BitSet compatibleRegs(DalvInsn insn) {
79        RegisterSpecList regs = insn.getRegisters();
80        BitSet bits = new BitSet(3);
81
82        bits.set(0, unsignedFitsInByte(regs.get(0).getReg()));
83        bits.set(1, unsignedFitsInByte(regs.get(1).getReg()));
84        bits.set(2, unsignedFitsInByte(regs.get(2).getReg()));
85        return bits;
86    }
87
88    /** {@inheritDoc} */
89    @Override
90    public void writeTo(AnnotatedOutput out, DalvInsn insn) {
91        RegisterSpecList regs = insn.getRegisters();
92        write(out,
93              opcodeUnit(insn, regs.get(0).getReg()),
94              codeUnit(regs.get(1).getReg(), regs.get(2).getReg()));
95    }
96}
97