1 /* 2 * Copyright (c) 2001, 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.debugger.cdbg.basic; 26 27 import sun.jvm.hotspot.debugger.*; 28 import sun.jvm.hotspot.debugger.cdbg.*; 29 import sun.jvm.hotspot.utilities.Assert; 30 31 public class BasicBitType extends BasicIntType implements BitType { 32 // Integer type or lazy type 33 private Type underlyingType; 34 private int sizeInBits; 35 private int offset; 36 37 /** Underlying type of enum must be an integer type (or as yet 38 unresolved) */ 39 BasicBitType(Type underlyingType, int sizeInBits, int lsbOffset)40 public BasicBitType(Type underlyingType, int sizeInBits, int lsbOffset) { 41 this(underlyingType, sizeInBits, lsbOffset, 0); 42 } 43 BasicBitType(Type underlyingType, int sizeInBits, int lsbOffset, int cvAttributes)44 private BasicBitType(Type underlyingType, int sizeInBits, int lsbOffset, int cvAttributes) { 45 super(null, 0, false, cvAttributes); 46 this.underlyingType = underlyingType; 47 this.sizeInBits = sizeInBits; 48 this.offset = lsbOffset; 49 } 50 asBit()51 public BitType asBit() { return this; } 52 getSize()53 public int getSize() { return underlyingType.getSize(); } isUnsigned()54 public boolean isUnsigned() { 55 if (underlyingType.isInt()) { 56 return ((IntType) underlyingType).isUnsigned(); 57 } 58 return false; 59 } 60 getSizeInBits()61 public int getSizeInBits() { 62 return sizeInBits; 63 } 64 getOffset()65 public int getOffset() { 66 return offset; 67 } 68 resolveTypes(BasicCDebugInfoDataBase db, ResolveListener listener)69 Type resolveTypes(BasicCDebugInfoDataBase db, ResolveListener listener) { 70 super.resolveTypes(db, listener); 71 underlyingType = db.resolveType(this, underlyingType, listener, "resolving bit type"); 72 setName(underlyingType.getName()); 73 if (Assert.ASSERTS_ENABLED) { 74 BasicType b = (BasicType) underlyingType; 75 Assert.that(b.isLazy() || b.isInt(), 76 "Underlying type of bitfield must be integer type (or unresolved due to error)"); 77 } 78 return this; 79 } 80 iterateObject(Address a, ObjectVisitor v, FieldIdentifier f)81 public void iterateObject(Address a, ObjectVisitor v, FieldIdentifier f) { 82 long mask = maskFor(sizeInBits); 83 long val = ((a.getCIntegerAt(0, getSize(), isUnsigned())) >> getOffset()) & mask; 84 if (!isUnsigned()) { 85 if ((val & highBit(sizeInBits)) != 0) { 86 // Must sign extend 87 val = val | (~mask); 88 } 89 } 90 v.doBit(f, val); 91 } 92 createCVVariant(int cvAttributes)93 protected Type createCVVariant(int cvAttributes) { 94 return new BasicBitType(underlyingType, getSizeInBits(), getOffset(), cvAttributes); 95 } 96 visit(TypeVisitor v)97 public void visit(TypeVisitor v) { 98 v.doBitType(this); 99 } 100 maskFor(int sizeInBits)101 private static long maskFor(int sizeInBits) { 102 return ((1 << sizeInBits) - 1); 103 } 104 highBit(int sizeInBits)105 private static long highBit(int sizeInBits) { 106 return (1 << (sizeInBits - 1)); 107 } 108 } 109