Mercurial > hg > truffle

comparison agent/src/share/classes/sun/jvm/hotspot/oops/BitData.java @ 3939:f6f3bb0ee072

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
7088955: add C2 IR support to the SA Reviewed-by: kvn
author never
date Sun, 11 Sep 2011 14:48:24 -0700
parents
children 79f492f184d0
comparison
equal deleted inserted replaced
3938:e6b1331a51d2 3939:f6f3bb0ee072
1 /*
2 * Copyright (c) 2011, 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 * have any questions.
22 *
23 */
24
25 package sun.jvm.hotspot.oops;
26
27 import java.io.*;
28 import java.util.*;
29 import sun.jvm.hotspot.debugger.*;
30 import sun.jvm.hotspot.runtime.*;
31 import sun.jvm.hotspot.types.*;
32 import sun.jvm.hotspot.utilities.*;
33
34 // BitData
35 //
36 // A BitData holds a flag or two in its header.
37 public class BitData extends ProfileData {
38
39 // nullSeen:
40 // saw a null operand (cast/aastore/instanceof)
41 static final int nullSeenFlag = DataLayout.firstFlag + 0;
42 static final int bitCellCount = 0;
43
44 public BitData(DataLayout layout) {
45 super(layout);
46 }
47
48 static int staticCellCount() {
49 return bitCellCount;
50 }
51
52 public int cellCount() {
53 return staticCellCount();
54 }
55
56 // Accessor
57
58 // The nullSeen flag bit is specially known to the interpreter.
59 // Consulting it allows the compiler to avoid setting up nullCheck traps.
60 boolean nullSeen() { return flagAt(nullSeenFlag); }
61
62 // Code generation support
63 // static int nullSeenByteConstant() {
64 // return flagNumberToByteConstant(nullSeenFlag);
65 // }
66
67 static int bitDataSize() {
68 return cellOffset(bitCellCount);
69 }
70
71 public void printDataOn(PrintStream st) {
72 printShared(st, "BitData");
73 }
74 }