SplitNode.java revision 1007:4258ccc2eb8a 
1/*
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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.
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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
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24 */
25
26package jdk.nashorn.internal.ir;
27
28import java.util.ArrayList;
29import java.util.Collections;
30import java.util.HashMap;
31import java.util.List;
32import java.util.Map;
33import jdk.nashorn.internal.codegen.CompileUnit;
34import jdk.nashorn.internal.codegen.Label;
35import jdk.nashorn.internal.ir.annotations.Immutable;
36import jdk.nashorn.internal.ir.visitor.NodeVisitor;
37
38/**
39 * Node indicating code is split across classes.
40 */
41@Immutable
42public class SplitNode extends LexicalContextStatement implements Labels, CompileUnitHolder {
43    /** Split node method name. */
44    private final String name;
45
46    /** Compilation unit. */
47    private final CompileUnit compileUnit;
48
49    /** Body of split code. */
50    private final Block body;
51
52    private Map<Label, JoinPredecessor> jumps;
53
54    /**
55     * Constructor
56     *
57     * @param name        name of split node
58     * @param body        body of split code
59     * @param compileUnit compile unit to use for the body
60     */
61    public SplitNode(final String name, final Block body, final CompileUnit compileUnit) {
62        super(body.getFirstStatementLineNumber(), body.getToken(), body.getFinish());
63        this.name        = name;
64        this.body        = body;
65        this.compileUnit = compileUnit;
66    }
67
68    private SplitNode(final SplitNode splitNode, final Block body, final CompileUnit compileUnit, final Map<Label, JoinPredecessor> jumps) {
69        super(splitNode);
70        this.name        = splitNode.name;
71        this.body        = body;
72        this.compileUnit = compileUnit;
73        this.jumps       = jumps;
74    }
75
76    /**
77     * Get the body for this split node - i.e. the actual code it encloses
78     * @return body for split node
79     */
80    public Node getBody() {
81        return body;
82    }
83
84    private SplitNode setBody(final LexicalContext lc, final Block body) {
85        if (this.body == body) {
86            return this;
87        }
88        return Node.replaceInLexicalContext(lc, this, new SplitNode(this, body, compileUnit, jumps));
89    }
90
91    @Override
92    public Node accept(final LexicalContext lc, final NodeVisitor<? extends LexicalContext> visitor) {
93        if (visitor.enterSplitNode(this)) {
94            return visitor.leaveSplitNode(setBody(lc, (Block)body.accept(visitor)));
95        }
96        return this;
97    }
98
99    @Override
100    public void toString(final StringBuilder sb, final boolean printType) {
101        sb.append("<split>(");
102        sb.append(compileUnit.getClass().getSimpleName());
103        sb.append(") ");
104        body.toString(sb, printType);
105    }
106
107    /**
108     * Get the name for this split node
109     * @return name
110     */
111    public String getName() {
112        return name;
113    }
114
115    /**
116     * Get the compile unit for this split node
117     * @return compile unit
118     */
119    @Override
120    public CompileUnit getCompileUnit() {
121        return compileUnit;
122    }
123
124    /**
125     * Set the compile unit for this split node
126     * @param lc lexical context
127     * @param compileUnit compile unit
128     * @return new node if changed, otherwise same node
129     */
130    public SplitNode setCompileUnit(final LexicalContext lc, final CompileUnit compileUnit) {
131        if (this.compileUnit == compileUnit) {
132            return this;
133        }
134        return Node.replaceInLexicalContext(lc, this, new SplitNode(this, body, compileUnit, jumps));
135    }
136
137    /**
138     * Adds a jump that crosses this split node's boundary (it originates within the split node, and goes to a target
139     * outside of it).
140     * @param jumpOrigin the join predecessor that's the origin of the jump
141     * @param targetLabel the label that's the target of the jump.
142     */
143    public void addJump(final JoinPredecessor jumpOrigin, final Label targetLabel) {
144        if (jumps == null) {
145            jumps = new HashMap<>();
146        }
147        jumps.put(targetLabel, jumpOrigin);
148    }
149
150    /**
151     * Returns the jump origin within this split node for a target.
152     * @param targetLabel the target for which a jump origin is sought.
153     * @return the jump origin, or null.
154     */
155    public JoinPredecessor getJumpOrigin(final Label targetLabel) {
156        return jumps == null ? null : jumps.get(targetLabel);
157    }
158
159    @Override
160    public List<Label> getLabels() {
161        return Collections.unmodifiableList(new ArrayList<>(jumps.keySet()));
162    }
163}
164