/*

 * Copyright (c) 2018, 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.

 *

 * 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

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

package sun.jvm.hotspot.gc.z;

import sun.jvm.hotspot.debugger.Address;

import sun.jvm.hotspot.runtime.VM;

import sun.jvm.hotspot.runtime.VMObject;

import sun.jvm.hotspot.runtime.VMObjectFactory;

import sun.jvm.hotspot.types.Type;

import sun.jvm.hotspot.types.TypeDataBase;

public class ZPageTable extends VMObject {

    private static long mapFieldOffset;

    static {

        VM.registerVMInitializedObserver((o, d) -> initialize(VM.getVM().getTypeDataBase()));

    }

    static private synchronized void initialize(TypeDataBase db) {

        Type type = db.lookupType("ZPageTable");

        mapFieldOffset = type.getAddressField("_map").getOffset();

    }

    public ZPageTable(Address addr) {

        super(addr);

    }

    private ZAddressRangeMapForPageTable map() {

        return (ZAddressRangeMapForPageTable)VMObjectFactory.newObject(ZAddressRangeMapForPageTable.class, addr.addOffsetTo(mapFieldOffset));

    }

    private ZPageTableEntry getEntry(Address o) {

        return new ZPageTableEntry(map().get(o));

    }

    ZPage get(Address o) {

        return getEntry(o).page();

    }

    boolean is_relocating(Address o) {

        return getEntry(o).relocating();

    }

}