1 /*
   2  * Copyright (c) 2009, 2019, 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.nodes;
  26 
  27 import org.graalvm.compiler.core.common.type.Stamp;
  28 import org.graalvm.compiler.graph.NodeClass;
  29 import org.graalvm.compiler.nodeinfo.NodeInfo;
  30 
  31 /**
  32  * The {@code ControlSplitNode} is a base class for all instructions that split the control flow
  33  * (ie. have more than one successor).
  34  */
  35 @NodeInfo
  36 public abstract class ControlSplitNode extends FixedNode {
  37     public static final NodeClass<ControlSplitNode> TYPE = NodeClass.create(ControlSplitNode.class);
  38 
  39     protected ControlSplitNode(NodeClass<? extends ControlSplitNode> c, Stamp stamp) {
  40         super(c, stamp);
  41     }
  42 
  43     public abstract double probability(AbstractBeginNode successor);
  44 
  45     /**
  46      * Attempts to set the probability for the given successor to the passed value (which has to be
  47      * in the range of 0.0 and 1.0). Returns whether setting the probability was successful.
  48      */
  49     public abstract boolean setProbability(AbstractBeginNode successor, double value);
  50 
  51     /**
  52      * Primary successor of the control split. Data dependencies on the node have to be scheduled in
  53      * the primary successor. Returns null if data dependencies are not expected.
  54      *
  55      * @return the primary successor
  56      */
  57     public abstract AbstractBeginNode getPrimarySuccessor();
  58 
  59     /**
  60      * Returns the number of successors.
  61      */
  62     public abstract int getSuccessorCount();
  63 }