1/*
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
3 *
4 * This code is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License version 2 only, as
6 * published by the Free Software Foundation.  Oracle designates this
7 * particular file as subject to the "Classpath" exception as provided
8 * by Oracle in the LICENSE file that accompanied this code.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 */
24
25/*
26 * This file is available under and governed by the GNU General Public
27 * License version 2 only, as published by the Free Software Foundation.
28 * However, the following notice accompanied the original version of this
29 * file:
30 *
31 * ASM: a very small and fast Java bytecode manipulation framework
32 * Copyright (c) 2000-2011 INRIA, France Telecom
33 * All rights reserved.
34 *
35 * Redistribution and use in source and binary forms, with or without
36 * modification, are permitted provided that the following conditions
37 * are met:
38 * 1. Redistributions of source code must retain the above copyright
39 *    notice, this list of conditions and the following disclaimer.
40 * 2. Redistributions in binary form must reproduce the above copyright
41 *    notice, this list of conditions and the following disclaimer in the
42 *    documentation and/or other materials provided with the distribution.
43 * 3. Neither the name of the copyright holders nor the names of its
44 *    contributors may be used to endorse or promote products derived from
45 *    this software without specific prior written permission.
46 *
47 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
48 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
49 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
50 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
51 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
52 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
53 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
54 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
55 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
56 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
57 * THE POSSIBILITY OF SUCH DAMAGE.
58 */
59package jdk.internal.org.objectweb.asm.commons;
60
61import jdk.internal.org.objectweb.asm.Handle;
62import jdk.internal.org.objectweb.asm.Label;
63import jdk.internal.org.objectweb.asm.MethodVisitor;
64import jdk.internal.org.objectweb.asm.Opcodes;
65
66/**
67 * A {@link MethodVisitor} that can be used to approximate method size.
68 *
69 * @author Eugene Kuleshov
70 */
71public class CodeSizeEvaluator extends MethodVisitor implements Opcodes {
72
73    private int minSize;
74
75    private int maxSize;
76
77    public CodeSizeEvaluator(final MethodVisitor mv) {
78        this(Opcodes.ASM5, mv);
79    }
80
81    protected CodeSizeEvaluator(final int api, final MethodVisitor mv) {
82        super(api, mv);
83    }
84
85    public int getMinSize() {
86        return this.minSize;
87    }
88
89    public int getMaxSize() {
90        return this.maxSize;
91    }
92
93    @Override
94    public void visitInsn(final int opcode) {
95        minSize += 1;
96        maxSize += 1;
97        if (mv != null) {
98            mv.visitInsn(opcode);
99        }
100    }
101
102    @Override
103    public void visitIntInsn(final int opcode, final int operand) {
104        if (opcode == SIPUSH) {
105            minSize += 3;
106            maxSize += 3;
107        } else {
108            minSize += 2;
109            maxSize += 2;
110        }
111        if (mv != null) {
112            mv.visitIntInsn(opcode, operand);
113        }
114    }
115
116    @Override
117    public void visitVarInsn(final int opcode, final int var) {
118        if (var < 4 && opcode != RET) {
119            minSize += 1;
120            maxSize += 1;
121        } else if (var >= 256) {
122            minSize += 4;
123            maxSize += 4;
124        } else {
125            minSize += 2;
126            maxSize += 2;
127        }
128        if (mv != null) {
129            mv.visitVarInsn(opcode, var);
130        }
131    }
132
133    @Override
134    public void visitTypeInsn(final int opcode, final String type) {
135        minSize += 3;
136        maxSize += 3;
137        if (mv != null) {
138            mv.visitTypeInsn(opcode, type);
139        }
140    }
141
142    @Override
143    public void visitFieldInsn(final int opcode, final String owner,
144            final String name, final String desc) {
145        minSize += 3;
146        maxSize += 3;
147        if (mv != null) {
148            mv.visitFieldInsn(opcode, owner, name, desc);
149        }
150    }
151
152    @Deprecated
153    @Override
154    public void visitMethodInsn(final int opcode, final String owner,
155            final String name, final String desc) {
156        if (api >= Opcodes.ASM5) {
157            super.visitMethodInsn(opcode, owner, name, desc);
158            return;
159        }
160        doVisitMethodInsn(opcode, owner, name, desc,
161                opcode == Opcodes.INVOKEINTERFACE);
162    }
163
164    @Override
165    public void visitMethodInsn(final int opcode, final String owner,
166            final String name, final String desc, final boolean itf) {
167        if (api < Opcodes.ASM5) {
168            super.visitMethodInsn(opcode, owner, name, desc, itf);
169            return;
170        }
171        doVisitMethodInsn(opcode, owner, name, desc, itf);
172    }
173
174    private void doVisitMethodInsn(int opcode, final String owner,
175            final String name, final String desc, final boolean itf) {
176        if (opcode == INVOKEINTERFACE) {
177            minSize += 5;
178            maxSize += 5;
179        } else {
180            minSize += 3;
181            maxSize += 3;
182        }
183        if (mv != null) {
184            mv.visitMethodInsn(opcode, owner, name, desc, itf);
185        }
186    }
187
188    @Override
189    public void visitInvokeDynamicInsn(String name, String desc, Handle bsm,
190            Object... bsmArgs) {
191        minSize += 5;
192        maxSize += 5;
193        if (mv != null) {
194            mv.visitInvokeDynamicInsn(name, desc, bsm, bsmArgs);
195        }
196    }
197
198    @Override
199    public void visitJumpInsn(final int opcode, final Label label) {
200        minSize += 3;
201        if (opcode == GOTO || opcode == JSR) {
202            maxSize += 5;
203        } else {
204            maxSize += 8;
205        }
206        if (mv != null) {
207            mv.visitJumpInsn(opcode, label);
208        }
209    }
210
211    @Override
212    public void visitLdcInsn(final Object cst) {
213        if (cst instanceof Long || cst instanceof Double) {
214            minSize += 3;
215            maxSize += 3;
216        } else {
217            minSize += 2;
218            maxSize += 3;
219        }
220        if (mv != null) {
221            mv.visitLdcInsn(cst);
222        }
223    }
224
225    @Override
226    public void visitIincInsn(final int var, final int increment) {
227        if (var > 255 || increment > 127 || increment < -128) {
228            minSize += 6;
229            maxSize += 6;
230        } else {
231            minSize += 3;
232            maxSize += 3;
233        }
234        if (mv != null) {
235            mv.visitIincInsn(var, increment);
236        }
237    }
238
239    @Override
240    public void visitTableSwitchInsn(final int min, final int max,
241            final Label dflt, final Label... labels) {
242        minSize += 13 + labels.length * 4;
243        maxSize += 16 + labels.length * 4;
244        if (mv != null) {
245            mv.visitTableSwitchInsn(min, max, dflt, labels);
246        }
247    }
248
249    @Override
250    public void visitLookupSwitchInsn(final Label dflt, final int[] keys,
251            final Label[] labels) {
252        minSize += 9 + keys.length * 8;
253        maxSize += 12 + keys.length * 8;
254        if (mv != null) {
255            mv.visitLookupSwitchInsn(dflt, keys, labels);
256        }
257    }
258
259    @Override
260    public void visitMultiANewArrayInsn(final String desc, final int dims) {
261        minSize += 4;
262        maxSize += 4;
263        if (mv != null) {
264            mv.visitMultiANewArrayInsn(desc, dims);
265        }
266    }
267}
268