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
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package jdk.nashorn.internal.codegen;
  27 
  28 import java.util.ArrayList;
  29 import java.util.List;
  30 import jdk.nashorn.internal.ir.CompileUnitHolder;
  31 import jdk.nashorn.internal.ir.FunctionNode;
  32 import jdk.nashorn.internal.ir.LiteralNode;
  33 import jdk.nashorn.internal.ir.LiteralNode.ArrayLiteralNode;
  34 import jdk.nashorn.internal.ir.Node;
  35 import jdk.nashorn.internal.ir.ObjectNode;
  36 import jdk.nashorn.internal.ir.Splittable;
  37 import jdk.nashorn.internal.ir.visitor.SimpleNodeVisitor;
  38 
  39 /**
  40  * Base class for a node visitor that replaces {@link CompileUnit}s in {@link CompileUnitHolder}s.
  41  */
  42 abstract class ReplaceCompileUnits extends SimpleNodeVisitor {
  43 
  44     /**
  45      * Override to provide a replacement for an old compile unit.
  46      * @param oldUnit the old compile unit to replace
  47      * @return the compile unit's replacement.
  48      */
  49     abstract CompileUnit getReplacement(final CompileUnit oldUnit);
  50 
  51     CompileUnit getExistingReplacement(final CompileUnitHolder node) {
  52         final CompileUnit oldUnit = node.getCompileUnit();
  53         assert oldUnit != null;
  54 
  55         final CompileUnit newUnit = getReplacement(oldUnit);
  56         assert newUnit != null;
  57 
  58         return newUnit;
  59     }
  60 
  61     @Override
  62     public Node leaveFunctionNode(final FunctionNode node) {
  63         return node.setCompileUnit(lc, getExistingReplacement(node));
  64     }
  65 
  66     @Override
  67     public Node leaveLiteralNode(final LiteralNode<?> node) {
  68         if (node instanceof ArrayLiteralNode) {
  69             final ArrayLiteralNode aln = (ArrayLiteralNode)node;
  70             if (aln.getSplitRanges() == null) {
  71                 return node;
  72             }
  73             final List<Splittable.SplitRange> newArrayUnits = new ArrayList<>();
  74             for (final Splittable.SplitRange au : aln.getSplitRanges()) {
  75                 newArrayUnits.add(new Splittable.SplitRange(getExistingReplacement(au), au.getLow(), au.getHigh()));
  76             }
  77             return aln.setSplitRanges(lc, newArrayUnits);
  78         }
  79         return node;
  80     }
  81 
  82     @Override
  83     public Node leaveObjectNode(final ObjectNode objectNode) {
  84         final List<Splittable.SplitRange> ranges = objectNode.getSplitRanges();
  85         if (ranges != null) {
  86             final List<Splittable.SplitRange> newRanges = new ArrayList<>();
  87             for (final Splittable.SplitRange range : ranges) {
  88                 newRanges.add(new Splittable.SplitRange(getExistingReplacement(range), range.getLow(), range.getHigh()));
  89             }
  90             return objectNode.setSplitRanges(lc, newRanges);
  91         }
  92         return super.leaveObjectNode(objectNode);
  93     }
  94 }