1 /*
   2  * Copyright (c) 2013, 2018, 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.nodes.spi.NodeWithState;
  28 
  29 /**
  30  * Interface implemented by nodes which may need {@linkplain FrameState deoptimization information}.
  31  * <p>
  32  * Sub-interfaces are used to specify exactly when the deoptimization can take place:
  33  * {@linkplain DeoptBefore before}, {@linkplain DeoptAfter after}, and/or {@linkplain DeoptDuring
  34  * during}. <br>
  35  * Note that these sub-interfaces are not mutually exclusive so that nodes that may deoptimize at
  36  * multiple times can be modeled.
  37  */
  38 public interface DeoptimizingNode extends NodeWithState {
  39 
  40     /**
  41      * Determines if this node needs deoptimization information.
  42      */
  43     boolean canDeoptimize();
  44 
  45     /**
  46      * Interface for nodes that need a {@link FrameState} for deoptimizing to a point before their
  47      * execution.
  48      */
  49     public interface DeoptBefore extends DeoptimizingNode {
  50 
  51         /**
  52          * Sets the {@link FrameState} describing the program state before the execution of this
  53          * node.
  54          */
  55         void setStateBefore(FrameState state);
  56 
  57         FrameState stateBefore();
  58     }
  59 
  60     /**
  61      * Interface for nodes that need a {@link FrameState} for deoptimizing to a point after their
  62      * execution.
  63      */
  64     public interface DeoptAfter extends DeoptimizingNode, StateSplit {
  65     }
  66 
  67     /**
  68      * Interface for nodes that need a special {@link FrameState} for deoptimizing during their
  69      * execution (e.g. {@link Invoke}).
  70      */
  71     public interface DeoptDuring extends DeoptimizingNode, StateSplit {
  72 
  73         FrameState stateDuring();
  74 
  75         /**
  76          * Sets the {@link FrameState} describing the program state during the execution of this
  77          * node.
  78          */
  79         void setStateDuring(FrameState state);
  80 
  81         /**
  82          * Compute the {@link FrameState} describing the program state during the execution of this
  83          * node from an input {@link FrameState} describing the program state after finishing the
  84          * execution of this node.
  85          */
  86         void computeStateDuring(FrameState stateAfter);
  87     }
  88 }