1 /*
2  * Copyright (c) 1994, 2003, Oracle and/or its affiliates. All rights reserved.
3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4  *
5  * This code is free software; you can redistribute it and/or modify it
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7  * published by the Free Software Foundation.  Oracle designates this
8  * particular file as subject to the "Classpath" exception as provided
9  * by Oracle in the LICENSE file that accompanied this code.
10  *
11  * This code is distributed in the hope that it will be useful, but WITHOUT
12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14  * version 2 for more details (a copy is included in the LICENSE file that
15  * accompanied this code).
16  *
17  * You should have received a copy of the GNU General Public License version
18  * 2 along with this work; if not, write to the Free Software Foundation,
19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20  *
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22  * or visit www.oracle.com if you need additional information or have any
23  * questions.
24  */
25 
26 package sun.tools.tree;
27 
28 import sun.tools.java.*;
29 import sun.tools.asm.Assembler;
30 import sun.tools.asm.Label;
31 
32 /**
33  * WARNING: The contents of this source file are not part of any
34  * supported API.  Code that depends on them does so at its own risk:
35  * they are subject to change or removal without notice.
36  */
37 public
38 class NotEqualExpression extends BinaryEqualityExpression {
39     /**
40      * constructor
41      */
NotEqualExpression(long where, Expression left, Expression right)42     public NotEqualExpression(long where, Expression left, Expression right) {
43         super(NE, where, left, right);
44     }
45 
46     /**
47      * Evaluate
48      */
eval(int a, int b)49     Expression eval(int a, int b) {
50         return new BooleanExpression(where, a != b);
51     }
eval(long a, long b)52     Expression eval(long a, long b) {
53         return new BooleanExpression(where, a != b);
54     }
eval(float a, float b)55     Expression eval(float a, float b) {
56         return new BooleanExpression(where, a != b);
57     }
eval(double a, double b)58     Expression eval(double a, double b) {
59         return new BooleanExpression(where, a != b);
60     }
eval(boolean a, boolean b)61     Expression eval(boolean a, boolean b) {
62         return new BooleanExpression(where, a != b);
63     }
64 
65     /**
66      * Simplify
67      */
simplify()68     Expression simplify() {
69         if (left.isConstant() && !right.isConstant()) {
70             return new NotEqualExpression(where, right, left);
71         }
72         return this;
73     }
74 
75     /**
76      * Code
77      */
codeBranch(Environment env, Context ctx, Assembler asm, Label lbl, boolean whenTrue)78     void codeBranch(Environment env, Context ctx, Assembler asm, Label lbl, boolean whenTrue) {
79         left.codeValue(env, ctx, asm);
80         switch (left.type.getTypeCode()) {
81           case TC_BOOLEAN:
82           case TC_INT:
83             if (!right.equals(0)) {
84                 right.codeValue(env, ctx, asm);
85                 asm.add(where, whenTrue ? opc_if_icmpne : opc_if_icmpeq, lbl, whenTrue);
86                 return;
87             }
88             break;
89           case TC_LONG:
90             right.codeValue(env, ctx, asm);
91             asm.add(where, opc_lcmp);
92             break;
93           case TC_FLOAT:
94             right.codeValue(env, ctx, asm);
95             asm.add(where, opc_fcmpl);
96             break;
97           case TC_DOUBLE:
98             right.codeValue(env, ctx, asm);
99             asm.add(where, opc_dcmpl);
100             break;
101           case TC_ARRAY:
102           case TC_CLASS:
103           case TC_NULL:
104             if (right.equals(0)) {
105                 asm.add(where, whenTrue ? opc_ifnonnull : opc_ifnull, lbl, whenTrue);
106             } else {
107                 right.codeValue(env, ctx, asm);
108                 asm.add(where, whenTrue ? opc_if_acmpne : opc_if_acmpeq, lbl, whenTrue);
109             }
110             return;
111           default:
112             throw new CompilerError("Unexpected Type");
113         }
114         asm.add(where, whenTrue ? opc_ifne : opc_ifeq, lbl, whenTrue);
115     }
116 }
117