1 /*
   2  * Copyright (c) 2014, 2016, 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 package org.graalvm.compiler.hotspot.word;
  24 
  25 import static org.graalvm.compiler.hotspot.word.HotSpotOperation.HotspotOpcode.POINTER_EQ;
  26 import static org.graalvm.compiler.hotspot.word.HotSpotOperation.HotspotOpcode.POINTER_NE;
  27 import static org.graalvm.compiler.hotspot.word.HotSpotOperation.HotspotOpcode.READ_KLASS_POINTER;
  28 import static org.graalvm.compiler.hotspot.word.HotSpotOperation.HotspotOpcode.TO_KLASS_POINTER;
  29 
  30 import org.graalvm.compiler.core.common.LocationIdentity;
  31 import org.graalvm.compiler.word.Pointer;
  32 import org.graalvm.compiler.word.Word.Opcode;
  33 import org.graalvm.compiler.word.Word.Operation;
  34 
  35 /**
  36  * Marker type for a metaspace pointer to a type.
  37  */
  38 public abstract class KlassPointer extends MetaspacePointer {
  39 
  40     @HotSpotOperation(opcode = POINTER_EQ)
  41     public abstract boolean equal(KlassPointer other);
  42 
  43     @HotSpotOperation(opcode = POINTER_NE)
  44     public abstract boolean notEqual(KlassPointer other);
  45 
  46     @HotSpotOperation(opcode = TO_KLASS_POINTER)
  47     public static native KlassPointer fromWord(Pointer pointer);
  48 
  49     @HotSpotOperation(opcode = READ_KLASS_POINTER)
  50     public native KlassPointer readKlassPointer(int offset, LocationIdentity locationIdentity);
  51 
  52     @Operation(opcode = Opcode.WRITE_POINTER)
  53     public native void writeKlassPointer(int offset, KlassPointer t, LocationIdentity locationIdentity);
  54 }