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.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 
  25 package org.graalvm.compiler.graph;
  26 
  27 import org.graalvm.compiler.nodeinfo.InputType;
  28 
  29 /**
  30  * Describes an edge slot for a {@link NodeClass}.
  31  */
  32 public final class Position {
  33 
  34     /**
  35      * The edges in which this position lies.
  36      */
  37     private final Edges edges;
  38 
  39     /**
  40      * Index of the {@link Node} or {@link NodeList} field denoted by this position.
  41      */
  42     private final int index;
  43 
  44     /**
  45      * Index within a {@link NodeList} if {@link #index} denotes a {@link NodeList} field otherwise
  46      * {@link Node#NOT_ITERABLE}.
  47      */
  48     private final int subIndex;
  49 
  50     public Position(Edges edges, int index, int subIndex) {
  51         this.edges = edges;
  52         this.index = index;
  53         this.subIndex = subIndex;
  54     }
  55 
  56     public Node get(Node node) {
  57         if (index < edges.getDirectCount()) {
  58             return Edges.getNode(node, edges.getOffsets(), index);
  59         } else {
  60             return Edges.getNodeList(node, edges.getOffsets(), index).get(subIndex);
  61         }
  62     }
  63 
  64     public InputType getInputType() {
  65         return ((InputEdges) edges).getInputType(index);
  66     }
  67 
  68     public String getName() {
  69         return edges.getName(index);
  70     }
  71 
  72     public boolean isInputOptional() {
  73         return ((InputEdges) edges).isOptional(index);
  74     }
  75 
  76     public void set(Node node, Node value) {
  77         if (index < edges.getDirectCount()) {
  78             edges.setNode(node, index, value);
  79         } else {
  80             Edges.getNodeList(node, edges.getOffsets(), index).set(subIndex, value);
  81         }
  82     }
  83 
  84     public void initialize(Node node, Node value) {
  85         if (index < edges.getDirectCount()) {
  86             edges.initializeNode(node, index, value);
  87         } else {
  88             Edges.getNodeList(node, edges.getOffsets(), index).initialize(subIndex, value);
  89         }
  90     }
  91 
  92     @Override
  93     public String toString() {
  94         String res = edges.getType(index).getSimpleName() + ":" + edges.getName(index);
  95         if (subIndex != Node.NOT_ITERABLE) {
  96             res += "[" + subIndex + "]";
  97         }
  98         return res;
  99     }
 100 
 101     @Override
 102     public int hashCode() {
 103         final int prime = 31;
 104         int result = 1;
 105         result = prime * result + index;
 106         result = prime * result + edges.hashCode();
 107         result = prime * result + subIndex;
 108         return result;
 109     }
 110 
 111     @Override
 112     public boolean equals(Object obj) {
 113         if (this == obj) {
 114             return true;
 115         }
 116         if (obj == null) {
 117             return false;
 118         }
 119         if (getClass() != obj.getClass()) {
 120             return false;
 121         }
 122         Position other = (Position) obj;
 123         if (index != other.index) {
 124             return false;
 125         }
 126         if (edges != other.edges) {
 127             return false;
 128         }
 129         if (subIndex != other.subIndex) {
 130             return false;
 131         }
 132         return true;
 133     }
 134 
 135     /**
 136      * Gets the index within a {@link NodeList} if {@link #getIndex()} denotes a {@link NodeList}
 137      * field otherwise {@link Node#NOT_ITERABLE}.
 138      */
 139     public int getSubIndex() {
 140         return subIndex;
 141     }
 142 
 143     /**
 144      * Gets the index of the {@link Node} or {@link NodeList} field denoted by this position.
 145      */
 146     public int getIndex() {
 147         return index;
 148     }
 149 }