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.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package jdk.nashorn.internal.ir;
  27 
  28 import jdk.nashorn.internal.codegen.CompilerConstants;
  29 import jdk.nashorn.internal.codegen.types.Type;
  30 import jdk.nashorn.internal.ir.annotations.Ignore;
  31 import jdk.nashorn.internal.ir.visitor.NodeVisitor;
  32 import jdk.nashorn.internal.runtime.Scope;
  33 
  34 /**
  35  * Synthetic AST node that represents loading of the scope object and invocation of the {@link Scope#getSplitState()}
  36  * method on it. It has no JavaScript source representation and only occurs in synthetic functions created by
  37  * the split-into-functions transformation.
  38  */
  39 public final class GetSplitState extends Expression {
  40     private static final long serialVersionUID = 1L;
  41 
  42     /** The sole instance of this AST node. */
  43     @Ignore
  44     public final static GetSplitState INSTANCE = new GetSplitState();
  45 
  46     private GetSplitState() {
  47         super(NO_TOKEN, NO_FINISH);
  48     }
  49 
  50     @Override
  51     public Type getType() {
  52         return Type.INT;
  53     }
  54 
  55     @Override
  56     public Node accept(final NodeVisitor<? extends LexicalContext> visitor) {
  57         return visitor.enterGetSplitState(this) ? visitor.leaveGetSplitState(this) : this;
  58     }
  59 
  60     @Override
  61     public void toString(final StringBuilder sb, final boolean printType) {
  62         if (printType) {
  63             sb.append("{I}");
  64         }
  65         sb.append(CompilerConstants.SCOPE.symbolName()).append('.').append(Scope.GET_SPLIT_STATE.name()).append("()");
  66     }
  67 
  68     private Object readResolve() {
  69         return INSTANCE;
  70     }
  71 }