2
|
1 |
/*
|
|
2 |
* Copyright 1994-2003 Sun Microsystems, Inc. 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. Sun designates this
|
|
8 |
* particular file as subject to the "Classpath" exception as provided
|
|
9 |
* by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
|
|
22 |
* CA 95054 USA or visit www.sun.com if you need additional information or
|
|
23 |
* have any 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 |
import java.util.Hashtable;
|
|
32 |
|
|
33 |
/**
|
|
34 |
* WARNING: The contents of this source file are not part of any
|
|
35 |
* supported API. Code that depends on them does so at its own risk:
|
|
36 |
* they are subject to change or removal without notice.
|
|
37 |
*/
|
|
38 |
public
|
|
39 |
class OrExpression extends BinaryLogicalExpression {
|
|
40 |
/**
|
|
41 |
* constructor
|
|
42 |
*/
|
|
43 |
public OrExpression(long where, Expression left, Expression right) {
|
|
44 |
super(OR, where, left, right);
|
|
45 |
}
|
|
46 |
|
|
47 |
/*
|
|
48 |
* Check an "or" expression.
|
|
49 |
*
|
|
50 |
* cvars is modified so that
|
|
51 |
* cvar.vsTrue indicates variables with a known value if
|
|
52 |
* either the left and right hand side isn true
|
|
53 |
* cvars.vsFalse indicates variables with a known value if
|
|
54 |
* both the left or right hand side are false
|
|
55 |
*/
|
|
56 |
public void checkCondition(Environment env, Context ctx, Vset vset,
|
|
57 |
Hashtable exp, ConditionVars cvars) {
|
|
58 |
// Find out when the left side is true/false
|
|
59 |
left.checkCondition(env, ctx, vset, exp, cvars);
|
|
60 |
left = convert(env, ctx, Type.tBoolean, left);
|
|
61 |
Vset vsTrue = cvars.vsTrue.copy();
|
|
62 |
Vset vsFalse = cvars.vsFalse.copy();
|
|
63 |
|
|
64 |
// Only look at the right side if the left side is false
|
|
65 |
right.checkCondition(env, ctx, vsFalse, exp, cvars);
|
|
66 |
right = convert(env, ctx, Type.tBoolean, right);
|
|
67 |
|
|
68 |
// cvars.vsFalse actually reports that both returned false
|
|
69 |
// cvars.vsTrue must be set back to either left side or the right
|
|
70 |
// side returning false;
|
|
71 |
cvars.vsTrue = cvars.vsTrue.join(vsTrue);
|
|
72 |
}
|
|
73 |
|
|
74 |
/**
|
|
75 |
* Evaluate
|
|
76 |
*/
|
|
77 |
Expression eval(boolean a, boolean b) {
|
|
78 |
return new BooleanExpression(where, a || b);
|
|
79 |
}
|
|
80 |
|
|
81 |
/**
|
|
82 |
* Simplify
|
|
83 |
*/
|
|
84 |
Expression simplify() {
|
|
85 |
if (right.equals(false)) {
|
|
86 |
return left;
|
|
87 |
}
|
|
88 |
if (left.equals(true)) {
|
|
89 |
return left;
|
|
90 |
}
|
|
91 |
if (left.equals(false)) {
|
|
92 |
return right;
|
|
93 |
}
|
|
94 |
if (right.equals(true)) {
|
|
95 |
// Preserve effects of left argument.
|
|
96 |
return new CommaExpression(where, left, right).simplify();
|
|
97 |
}
|
|
98 |
return this;
|
|
99 |
}
|
|
100 |
|
|
101 |
/**
|
|
102 |
* Code
|
|
103 |
*/
|
|
104 |
void codeBranch(Environment env, Context ctx, Assembler asm, Label lbl, boolean whenTrue) {
|
|
105 |
if (whenTrue) {
|
|
106 |
left.codeBranch(env, ctx, asm, lbl, true);
|
|
107 |
right.codeBranch(env, ctx, asm, lbl, true);
|
|
108 |
} else {
|
|
109 |
Label lbl2 = new Label();
|
|
110 |
left.codeBranch(env, ctx, asm, lbl2, true);
|
|
111 |
right.codeBranch(env, ctx, asm, lbl, false);
|
|
112 |
asm.add(lbl2);
|
|
113 |
}
|
|
114 |
}
|
|
115 |
}
|