1 /*
   2  * Copyright (c) 2013, 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.phases.common.util;
  24 
  25 import java.util.EnumSet;
  26 import java.util.HashSet;
  27 import java.util.Set;
  28 
  29 import org.graalvm.compiler.graph.Graph.NodeEvent;
  30 import org.graalvm.compiler.graph.Graph.NodeEventListener;
  31 import org.graalvm.compiler.graph.Node;
  32 import org.graalvm.compiler.graph.Node.IndirectCanonicalization;
  33 
  34 /**
  35  * A simple {@link NodeEventListener} implementation that accumulates event nodes in a
  36  * {@link HashSet}.
  37  */
  38 public class HashSetNodeEventListener implements NodeEventListener {
  39 
  40     private final Set<Node> nodes;
  41     private final Set<NodeEvent> filter;
  42 
  43     /**
  44      * Creates a {@link NodeEventListener} that collects nodes from all events.
  45      */
  46     public HashSetNodeEventListener() {
  47         this.nodes = Node.newSet();
  48         this.filter = EnumSet.allOf(NodeEvent.class);
  49     }
  50 
  51     /**
  52      * Creates a {@link NodeEventListener} that collects nodes from all events that match a given
  53      * filter.
  54      */
  55     public HashSetNodeEventListener(Set<NodeEvent> filter) {
  56         this.nodes = Node.newSet();
  57         this.filter = filter;
  58     }
  59 
  60     /**
  61      * Excludes a given event from those for which nodes are collected.
  62      */
  63     public HashSetNodeEventListener exclude(NodeEvent e) {
  64         filter.remove(e);
  65         return this;
  66     }
  67 
  68     @Override
  69     public void event(NodeEvent e, Node node) {
  70         if (filter.contains(e)) {
  71             nodes.add(node);
  72             if (node instanceof IndirectCanonicalization) {
  73                 for (Node usage : node.usages()) {
  74                     nodes.add(usage);
  75                 }
  76             }
  77         }
  78     }
  79 
  80     /**
  81      * Gets the set being used to accumulate the nodes communicated to this listener.
  82      */
  83     public Set<Node> getNodes() {
  84         return nodes;
  85     }
  86 }