/*
* Copyright (c) 2011, 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
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*/
package sun.jvm.hotspot.oops;
import java.io.*;
import java.util.*;
import sun.jvm.hotspot.debugger.*;
import sun.jvm.hotspot.runtime.*;
import sun.jvm.hotspot.types.*;
import sun.jvm.hotspot.utilities.*;
// BitData
//
// A BitData holds a flag or two in its header.
public class BitData extends ProfileData {
// nullSeen:
// saw a null operand (cast/aastore/instanceof)
static final int nullSeenFlag = DataLayout.firstFlag + 0;
static final int bitCellCount = 0;
public BitData(DataLayout layout) {
super(layout);
}
static int staticCellCount() {
return bitCellCount;
}
public int cellCount() {
return staticCellCount();
}
// Accessor
// The nullSeen flag bit is specially known to the interpreter.
// Consulting it allows the compiler to avoid setting up nullCheck traps.
boolean nullSeen() { return flagAt(nullSeenFlag); }
// Code generation support
// static int nullSeenByteConstant() {
// return flagNumberToByteConstant(nullSeenFlag);
// }
static int bitDataSize() {
return cellOffset(bitCellCount);
}
public void printDataOn(PrintStream st) {
printShared(st, "BitData");
}
}