001    /*
002     *  This file is part of the Jikes RVM project (http://jikesrvm.org).
003     *
004     *  This file is licensed to You under the Eclipse Public License (EPL);
005     *  You may not use this file except in compliance with the License. You
006     *  may obtain a copy of the License at
007     *
008     *      http://www.opensource.org/licenses/eclipse-1.0.php
009     *
010     *  See the COPYRIGHT.txt file distributed with this work for information
011     *  regarding copyright ownership.
012     */
013    package org.vmmagic.pragma;
014    
015    import java.lang.annotation.Retention;
016    import java.lang.annotation.Target;
017    import java.lang.annotation.RetentionPolicy;
018    import java.lang.annotation.ElementType;
019    
020    /**
021     * Use this annotation to mark fields that are read without the knowledge of the
022     * memory management system. This means that barriers are not triggered and
023     * the reference is also not traced by the garbage collector.<p>
024     *
025     * As annotations are loaded at class resolution time, fields marked with this
026     * annotation must be private so that no unresolved accesses are compiled to them with
027     * barriers.
028     */
029    @Retention(RetentionPolicy.RUNTIME)
030    @Target(ElementType.FIELD)
031    public @interface Untraced { }