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  */
59 package jdk.internal.org.objectweb.asm.tree.analysis;
60 
61 import jdk.internal.org.objectweb.asm.Type;
62 
63 /**
64  * A {@link Value} that is represented by its type in a seven types type system.
65  * This type system distinguishes the UNINITIALZED, INT, FLOAT, LONG, DOUBLE,
66  * REFERENCE and RETURNADDRESS types.
67  *
68  * @author Eric Bruneton
69  */
70 public class BasicValue implements Value {
71 
72     public static final BasicValue UNINITIALIZED_VALUE = new BasicValue(null);
73 
74     public static final BasicValue INT_VALUE = new BasicValue(Type.INT_TYPE);
75 
76     public static final BasicValue FLOAT_VALUE = new BasicValue(Type.FLOAT_TYPE);
77 
78     public static final BasicValue LONG_VALUE = new BasicValue(Type.LONG_TYPE);
79 
80     public static final BasicValue DOUBLE_VALUE = new BasicValue(
81             Type.DOUBLE_TYPE);
82 
83     public static final BasicValue REFERENCE_VALUE = new BasicValue(
84             Type.getObjectType("java/lang/Object"));
85 
86     public static final BasicValue RETURNADDRESS_VALUE = new BasicValue(
87             Type.VOID_TYPE);
88 
89     private final Type type;
90 
BasicValue(final Type type)91     public BasicValue(final Type type) {
92         this.type = type;
93     }
94 
getType()95     public Type getType() {
96         return type;
97     }
98 
getSize()99     public int getSize() {
100         return type == Type.LONG_TYPE || type == Type.DOUBLE_TYPE ? 2 : 1;
101     }
102 
isReference()103     public boolean isReference() {
104         return type != null
105                 && (type.getSort() == Type.OBJECT || type.getSort() == Type.ARRAY);
106     }
107 
108     @Override
equals(final Object value)109     public boolean equals(final Object value) {
110         if (value == this) {
111             return true;
112         } else if (value instanceof BasicValue) {
113             if (type == null) {
114                 return ((BasicValue) value).type == null;
115             } else {
116                 return type.equals(((BasicValue) value).type);
117             }
118         } else {
119             return false;
120         }
121     }
122 
123     @Override
hashCode()124     public int hashCode() {
125         return type == null ? 0 : type.hashCode();
126     }
127 
128     @Override
toString()129     public String toString() {
130         if (this == UNINITIALIZED_VALUE) {
131             return ".";
132         } else if (this == RETURNADDRESS_VALUE) {
133             return "A";
134         } else if (this == REFERENCE_VALUE) {
135             return "R";
136         } else {
137             return type.getDescriptor();
138         }
139     }
140 }
141