/*
 * Copyright (c) 2014, 2019, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package com.oracle.svm.core.genscavenge;

import org.graalvm.nativeimage.ImageSingletons;
import org.graalvm.nativeimage.IsolateThread;
import org.graalvm.word.Pointer;

import com.oracle.svm.core.c.NonmovableArray;
import com.oracle.svm.core.c.NonmovableArrays;
import com.oracle.svm.core.heap.GC;
import com.oracle.svm.core.heap.InstanceReferenceMapDecoder;
import com.oracle.svm.core.heap.ObjectReferenceVisitor;
import com.oracle.svm.core.thread.VMThreads;
import com.oracle.svm.core.threadlocal.VMThreadLocalMTSupport;

The class is registered with the GC to process VM thread local variables of type Object. /**
 * The class is registered with the {@link GC} to process VM thread local variables of type
 * {@link Object}.
 */
final class ThreadLocalMTWalker {
    static void walk(ObjectReferenceVisitor referenceVisitor) {
        VMThreadLocalMTSupport threadLocals = ImageSingletons.lookup(VMThreadLocalMTSupport.class);
        NonmovableArray<Byte> threadRefMapEncoding = NonmovableArrays.fromImageHeap(threadLocals.vmThreadReferenceMapEncoding);
        for (IsolateThread vmThread = VMThreads.firstThread(); vmThread.isNonNull(); vmThread = VMThreads.nextThread(vmThread)) {
            InstanceReferenceMapDecoder.walkOffsetsFromPointer((Pointer) vmThread, threadRefMapEncoding,
                            threadLocals.vmThreadReferenceMapIndex, referenceVisitor, null);
        }
    }
}