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 package org.graalvm.compiler.graph;
  24 
  25 import org.graalvm.compiler.nodeinfo.InputType;
  26 
  27 /**
  28  * Describes an edge slot for a {@link NodeClass}.
  29  */
  30 public final class Position {
  31 
  32     /**
  33      * The edges in which this position lies.
  34      */
  35     private final Edges edges;
  36 
  37     /**
  38      * Index of the {@link Node} or {@link NodeList} field denoted by this position.
  39      */
  40     private final int index;
  41 
  42     /**
  43      * Index within a {@link NodeList} if {@link #index} denotes a {@link NodeList} field otherwise
  44      * {@link Node#NOT_ITERABLE}.
  45      */
  46     private final int subIndex;
  47 
  48     public Position(Edges edges, int index, int subIndex) {
  49         this.edges = edges;
  50         this.index = index;
  51         this.subIndex = subIndex;
  52     }
  53 
  54     public Node get(Node node) {
  55         if (index < edges.getDirectCount()) {
  56             return Edges.getNode(node, edges.getOffsets(), index);
  57         } else {
  58             return Edges.getNodeList(node, edges.getOffsets(), index).get(subIndex);
  59         }
  60     }
  61 
  62     public InputType getInputType() {
  63         return ((InputEdges) edges).getInputType(index);
  64     }
  65 
  66     public String getName() {
  67         return edges.getName(index);
  68     }
  69 
  70     public boolean isInputOptional() {
  71         return ((InputEdges) edges).isOptional(index);
  72     }
  73 
  74     public void set(Node node, Node value) {
  75         if (index < edges.getDirectCount()) {
  76             edges.setNode(node, index, value);
  77         } else {
  78             Edges.getNodeList(node, edges.getOffsets(), index).set(subIndex, value);
  79         }
  80     }
  81 
  82     public void initialize(Node node, Node value) {
  83         if (index < edges.getDirectCount()) {
  84             edges.initializeNode(node, index, value);
  85         } else {
  86             Edges.getNodeList(node, edges.getOffsets(), index).initialize(subIndex, value);
  87         }
  88     }
  89 
  90     @Override
  91     public String toString() {
  92         String res = edges.getType(index).getSimpleName() + ":" + edges.getName(index);
  93         if (subIndex != Node.NOT_ITERABLE) {
  94             res += "[" + subIndex + "]";
  95         }
  96         return res;
  97     }
  98 
  99     @Override
 100     public int hashCode() {
 101         final int prime = 31;
 102         int result = 1;
 103         result = prime * result + index;
 104         result = prime * result + edges.hashCode();
 105         result = prime * result + subIndex;
 106         return result;
 107     }
 108 
 109     @Override
 110     public boolean equals(Object obj) {
 111         if (this == obj) {
 112             return true;
 113         }
 114         if (obj == null) {
 115             return false;
 116         }
 117         if (getClass() != obj.getClass()) {
 118             return false;
 119         }
 120         Position other = (Position) obj;
 121         if (index != other.index) {
 122             return false;
 123         }
 124         if (edges != other.edges) {
 125             return false;
 126         }
 127         if (subIndex != other.subIndex) {
 128             return false;
 129         }
 130         return true;
 131     }
 132 
 133     /**
 134      * Gets the index within a {@link NodeList} if {@link #getIndex()} denotes a {@link NodeList}
 135      * field otherwise {@link Node#NOT_ITERABLE}.
 136      */
 137     public int getSubIndex() {
 138         return subIndex;
 139     }
 140 
 141     /**
 142      * Gets the index of the {@link Node} or {@link NodeList} field denoted by this position.
 143      */
 144     public int getIndex() {
 145         return index;
 146     }
 147 }