1 /* 2 * Copyright (c) 2018, 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 */ 24 25 package sun.jvm.hotspot.gc.z; 26 27 import sun.jvm.hotspot.debugger.Address; 28 import sun.jvm.hotspot.debugger.OopHandle; 29 import sun.jvm.hotspot.runtime.VM; 30 import sun.jvm.hotspot.types.TypeDataBase; 31 import sun.jvm.hotspot.types.WrongTypeException; 32 33 class ZAddress { 34 35 private static long ZAddressWeakBadMask; 36 private static long ZAddressGoodMask; 37 private static long ZAddressOffsetMask; 38 39 static { 40 VM.registerVMInitializedObserver((o, d) -> initialize(VM.getVM().getTypeDataBase())); 41 } 42 43 private static synchronized void initialize(TypeDataBase db) throws WrongTypeException { 44 ZAddressWeakBadMask = db.lookupLongConstant("ZAddressWeakBadMask").longValue(); 45 ZAddressGoodMask = db.lookupLongConstant("ZAddressGoodMask").longValue(); 46 ZAddressOffsetMask = db.lookupLongConstant("ZAddressOffsetMask").longValue(); 47 } 48 49 static long as_long(Address value) { 50 if (value == null) { 51 return 0; 52 } 53 return value.asLongValue(); 54 }; 55 56 static boolean is_null(Address value) { 57 return value == null; 58 } 59 60 static boolean is_weak_bad(Address value) { 61 return (as_long(value) & ZAddressWeakBadMask) != 0; 62 } 63 64 static boolean is_weak_good(Address value) { 65 return !is_weak_bad(value) && !is_null(value); 66 } 67 68 static boolean is_weak_good_or_null(Address value) { 69 return !is_weak_bad(value); 70 } 71 72 static Address offset(Address address) { 73 return address.andWithMask(ZAddressOffsetMask); 74 } 75 76 static Address address(Address addr) { 77 // TODO: Linux-specific - We don't use a heap base on Linux 78 return ZOop.to_address(addr); 79 } 80 81 static Address good(Address value) { 82 return address(offset(value).orWithMask(ZAddressGoodMask)); 83 } 84 85 static Address good_or_null(Address value) { 86 return is_null(value) ? value : good(value); 87 } 88 }