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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
6    * under the terms of the GNU General Public License version 2 only, as
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   *
21   * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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 java.io.PrintStream;
30  import java.util.Hashtable;
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 UnaryExpression extends Expression {
39      Expression right;
40  
41      /**
42       * Constructor
43       */
44      UnaryExpression(int op, long where, Type type, Expression right) {
45          super(op, where, type);
46          this.right = right;
47      }
48  
49      /**
50       * Order the expression based on precedence
51       */
52      public Expression order() {
53          if (precedence() > right.precedence()) {
54              UnaryExpression e = (UnaryExpression)right;
55              right = e.right;
56              e.right = order();
57              return e;
58          }
59          return this;
60      }
61  
62      /**
63       * Select the type of the expression
64       */
65      void selectType(Environment env, Context ctx, int tm) {
66          throw new CompilerError("selectType: " + opNames[op]);
67      }
68  
69      /**
70       * Check a unary expression
71       */
72      public Vset checkValue(Environment env, Context ctx, Vset vset, Hashtable exp) {
73          vset = right.checkValue(env, ctx, vset, exp);
74  
75          int tm = right.type.getTypeMask();
76          selectType(env, ctx, tm);
77          if (((tm & TM_ERROR) == 0) && type.isType(TC_ERROR)) {
78              env.error(where, "invalid.arg", opNames[op]);
79          }
80          return vset;
81      }
82  
83      /**
84       * Check if constant
85       */
86      public boolean isConstant() {
87          switch (op) {
88          case POS:
89          case NEG:
90          case BITNOT:
91          case NOT:
92          case EXPR:
93          case CONVERT: // generated inside of CastExpression
94              return right.isConstant();
95          }
96          return false;
97      }
98  
99      /**
100      * Evaluate
101      */
102     Expression eval(int a) {
103         return this;
104     }
105     Expression eval(long a) {
106         return this;
107     }
108     Expression eval(float a) {
109         return this;
110     }
111     Expression eval(double a) {
112         return this;
113     }
114     Expression eval(boolean a) {
115         return this;
116     }
117     Expression eval(String a) {
118         return this;
119     }
120     Expression eval() {
121         switch (right.op) {
122           case BYTEVAL:
123           case CHARVAL:
124           case SHORTVAL:
125           case INTVAL:
126             return eval(((IntegerExpression)right).value);
127           case LONGVAL:
128             return eval(((LongExpression)right).value);
129           case FLOATVAL:
130             return eval(((FloatExpression)right).value);
131           case DOUBLEVAL:
132             return eval(((DoubleExpression)right).value);
133           case BOOLEANVAL:
134             return eval(((BooleanExpression)right).value);
135           case STRINGVAL:
136             return eval(((StringExpression)right).value);
137         }
138         return this;
139     }
140 
141     /**
142      * Inline
143      */
144     public Expression inline(Environment env, Context ctx) {
145         return right.inline(env, ctx);
146     }
147     public Expression inlineValue(Environment env, Context ctx) {
148         right = right.inlineValue(env, ctx);
149         try {
150             return eval().simplify();
151         } catch (ArithmeticException e) {
152             // Got rid of this error message.  It isn't illegal to
153             // have a program which does a constant division by
154             // zero.  We return `this' to make the compiler to
155             // generate code here.
156             // (bugs 4019304, 4089107).
157             //
158             // I am not positive that this catch is ever reached.
159             //
160             // env.error(where, "arithmetic.exception");
161             return this;
162         }
163     }
164 
165     /**
166      * Create a copy of the expression for method inlining
167      */
168     public Expression copyInline(Context ctx) {
169         UnaryExpression e = (UnaryExpression)clone();
170         if (right != null) {
171             e.right = right.copyInline(ctx);
172         }
173         return e;
174     }
175 
176     /**
177      * The cost of inlining this expression
178      */
179     public int costInline(int thresh, Environment env, Context ctx) {
180         return 1 + right.costInline(thresh, env, ctx);
181     }
182 
183     /**
184      * Print
185      */
186     public void print(PrintStream out) {
187         out.print("(" + opNames[op] + " ");
188         right.print(out);
189         out.print(")");
190     }
191 }