BooleanType.java revision 1324:7e06231229fd 
1/*
2 * Copyright (c) 2010, 2013, 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
26package jdk.nashorn.internal.codegen.types;
27
28import static jdk.internal.org.objectweb.asm.Opcodes.I2D;
29import static jdk.internal.org.objectweb.asm.Opcodes.I2L;
30import static jdk.internal.org.objectweb.asm.Opcodes.IADD;
31import static jdk.internal.org.objectweb.asm.Opcodes.ICONST_0;
32import static jdk.internal.org.objectweb.asm.Opcodes.ICONST_1;
33import static jdk.internal.org.objectweb.asm.Opcodes.ILOAD;
34import static jdk.internal.org.objectweb.asm.Opcodes.IRETURN;
35import static jdk.internal.org.objectweb.asm.Opcodes.ISTORE;
36import static jdk.nashorn.internal.codegen.CompilerConstants.staticCallNoLookup;
37import static jdk.nashorn.internal.runtime.JSType.UNDEFINED_INT;
38import static jdk.nashorn.internal.runtime.UnwarrantedOptimismException.INVALID_PROGRAM_POINT;
39
40import jdk.internal.org.objectweb.asm.MethodVisitor;
41import jdk.nashorn.internal.codegen.CompilerConstants;
42
43/**
44 * The boolean type class
45 */
46public final class BooleanType extends Type {
47    private static final long serialVersionUID = 1L;
48
49    private static final CompilerConstants.Call VALUE_OF = staticCallNoLookup(Boolean.class, "valueOf", Boolean.class, boolean.class);
50    private static final CompilerConstants.Call TO_STRING = staticCallNoLookup(Boolean.class, "toString", String.class, boolean.class);
51
52    /**
53     * Constructor
54     */
55    protected BooleanType() {
56        super("boolean", boolean.class, 1, 1);
57    }
58
59    @Override
60    public Type nextWider() {
61        return INT;
62    }
63
64    @Override
65    public Class<?> getBoxedType() {
66        return Boolean.class;
67    }
68
69    @Override
70    public char getBytecodeStackType() {
71        return 'I';
72    }
73
74    @Override
75    public Type loadUndefined(final MethodVisitor method) {
76        method.visitLdcInsn(UNDEFINED_INT);
77        return BOOLEAN;
78    }
79
80    @Override
81    public Type loadForcedInitializer(final MethodVisitor method) {
82        method.visitInsn(ICONST_0);
83        return BOOLEAN;
84    }
85
86    @Override
87    public void _return(final MethodVisitor method) {
88        method.visitInsn(IRETURN);
89    }
90
91    @Override
92    public Type load(final MethodVisitor method, final int slot) {
93        assert slot != -1;
94        method.visitVarInsn(ILOAD, slot);
95        return BOOLEAN;
96    }
97
98    @Override
99    public void store(final MethodVisitor method, final int slot) {
100        assert slot != -1;
101        method.visitVarInsn(ISTORE, slot);
102    }
103
104    @Override
105    public Type ldc(final MethodVisitor method, final Object c) {
106        assert c instanceof Boolean;
107        method.visitInsn((Boolean) c ? ICONST_1 : ICONST_0);
108        return BOOLEAN;
109    }
110
111    @Override
112    public Type convert(final MethodVisitor method, final Type to) {
113        if (isEquivalentTo(to)) {
114            return to;
115        }
116
117        if (to.isNumber()) {
118            method.visitInsn(I2D);
119        } else if (to.isLong()) {
120            method.visitInsn(I2L);
121        } else if (to.isInteger()) {
122            //nop
123        } else if (to.isString()) {
124            invokestatic(method, TO_STRING);
125        } else if (to.isObject()) {
126            invokestatic(method, VALUE_OF);
127        } else {
128            throw new UnsupportedOperationException("Illegal conversion " + this + " -> " + to);
129        }
130
131        return to;
132    }
133
134    @Override
135    public Type add(final MethodVisitor method, final int programPoint) {
136        // Adding booleans in JavaScript is perfectly valid, they add as if false=0 and true=1
137        if(programPoint == INVALID_PROGRAM_POINT) {
138            method.visitInsn(IADD);
139        } else {
140            method.visitInvokeDynamicInsn("iadd", "(II)I", MATHBOOTSTRAP, programPoint);
141        }
142        return INT;
143    }
144}
145