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;
18
19import com.android.dx.rop.code.RegisterSpecList;
20import com.android.dx.rop.code.SourcePosition;
21import com.android.dx.util.AnnotatedOutput;
22
23/**
24 * Base class for instructions which are of a fixed code size and
25 * which use {@link InsnFormat} methods to write themselves. This
26 * includes most — but not all — instructions.
27 */
28public abstract class FixedSizeInsn extends DalvInsn {
29    /**
30     * Constructs an instance. The output address of this instance is initially
31     * unknown ({@code -1}).
32     *
33     * <p><b>Note:</b> In the unlikely event that an instruction takes
34     * absolutely no registers (e.g., a {@code nop} or a
35     * no-argument no-result * static method call), then the given
36     * register list may be passed as {@link
37     * RegisterSpecList#EMPTY}.</p>
38     *
39     * @param opcode the opcode; one of the constants from {@link Dops}
40     * @param position {@code non-null;} source position
41     * @param registers {@code non-null;} register list, including a
42     * result register if appropriate (that is, registers may be either
43     * ins or outs)
44     */
45    public FixedSizeInsn(Dop opcode, SourcePosition position,
46                         RegisterSpecList registers) {
47        super(opcode, position, registers);
48    }
49
50    /** {@inheritDoc} */
51    @Override
52    public final int codeSize() {
53        return getOpcode().getFormat().codeSize();
54    }
55
56    /** {@inheritDoc} */
57    @Override
58    public final void writeTo(AnnotatedOutput out) {
59        getOpcode().getFormat().writeTo(out, this);
60    }
61
62    /** {@inheritDoc} */
63    @Override
64    public final DalvInsn withRegisterOffset(int delta) {
65        return withRegisters(getRegisters().withOffset(delta));
66    }
67
68    /** {@inheritDoc} */
69    @Override
70    protected final String listingString0(boolean noteIndices) {
71        return getOpcode().getFormat().listingString(this, noteIndices);
72    }
73}
74