ReplaceCompileUnits.java revision 1426:751ada854e5a 
1/*
2 * Copyright (c) 2014, 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
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24 */
25
26package jdk.nashorn.internal.codegen;
27
28import java.util.ArrayList;
29import java.util.List;
30import jdk.nashorn.internal.ir.CompileUnitHolder;
31import jdk.nashorn.internal.ir.FunctionNode;
32import jdk.nashorn.internal.ir.LexicalContext;
33import jdk.nashorn.internal.ir.LiteralNode;
34import jdk.nashorn.internal.ir.LiteralNode.ArrayLiteralNode;
35import jdk.nashorn.internal.ir.LiteralNode.ArrayLiteralNode.ArrayUnit;
36import jdk.nashorn.internal.ir.Node;
37import jdk.nashorn.internal.ir.visitor.NodeVisitor;
38
39/**
40 * Base class for a node visitor that replaces {@link CompileUnit}s in {@link CompileUnitHolder}s.
41 */
42abstract class ReplaceCompileUnits extends NodeVisitor<LexicalContext> {
43    ReplaceCompileUnits() {
44        super(new LexicalContext());
45    }
46
47    /**
48     * Override to provide a replacement for an old compile unit.
49     * @param oldUnit the old compile unit to replace
50     * @return the compile unit's replacement.
51     */
52    abstract CompileUnit getReplacement(final CompileUnit oldUnit);
53
54    CompileUnit getExistingReplacement(final CompileUnitHolder node) {
55        final CompileUnit oldUnit = node.getCompileUnit();
56        assert oldUnit != null;
57
58        final CompileUnit newUnit = getReplacement(oldUnit);
59        assert newUnit != null;
60
61        return newUnit;
62    }
63
64    @Override
65    public Node leaveFunctionNode(final FunctionNode node) {
66        return node.setCompileUnit(lc, getExistingReplacement(node));
67    }
68
69    @Override
70    public Node leaveLiteralNode(final LiteralNode<?> node) {
71        if (node instanceof ArrayLiteralNode) {
72            final ArrayLiteralNode aln = (ArrayLiteralNode)node;
73            if (aln.getUnits() == null) {
74                return node;
75            }
76            final List<ArrayUnit> newArrayUnits = new ArrayList<>();
77            for (final ArrayUnit au : aln.getUnits()) {
78                newArrayUnits.add(new ArrayUnit(getExistingReplacement(au), au.getLo(), au.getHi()));
79            }
80            return aln.setUnits(lc, newArrayUnits);
81        }
82        return node;
83    }
84}
85