OopMapStream.java revision 9883:903a2e023ffb 
1/*
2 * Copyright (c) 2000, 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
25package sun.jvm.hotspot.compiler;
26
27import sun.jvm.hotspot.code.*;
28
29public class OopMapStream {
30  private CompressedReadStream stream;
31  private ImmutableOopMap oopMap;
32  private int mask;
33  private int size;
34  private int position;
35  private OopMapValue omv;
36  private boolean omvValid;
37
38  public OopMapStream(ImmutableOopMap oopMap) {
39    this(oopMap, (OopMapValue.OopTypes[]) null);
40  }
41
42  public OopMapStream(ImmutableOopMap oopMap, OopMapValue.OopTypes type) {
43    this(oopMap, (OopMapValue.OopTypes[]) null);
44    mask = type.getValue();
45  }
46
47  public OopMapStream(ImmutableOopMap oopMap, OopMapValue.OopTypes[] types) {
48    stream = new CompressedReadStream(oopMap.getData());
49    mask = computeMask(types);
50    size = (int) oopMap.getCount();
51    position = 0;
52    omv = new OopMapValue();
53    omvValid = false;
54  }
55
56  public boolean isDone() {
57    if (!omvValid) {
58      findNext();
59    }
60    return !omvValid;
61  }
62
63  public void next() {
64    findNext();
65  }
66
67  public OopMapValue getCurrent() {
68    return omv;
69  }
70
71  //--------------------------------------------------------------------------------
72  // Internals only below this point
73  //
74
75  private int computeMask(OopMapValue.OopTypes[] types) {
76    mask = 0;
77    if (types != null) {
78      for (int i = 0; i < types.length; i++) {
79        mask |= types[i].getValue();
80      }
81    }
82    return mask;
83  }
84
85  private void findNext() {
86    while (position++ < size) {
87      omv.readFrom(stream);
88      if ((omv.getType().getValue() & mask) > 0) {
89        omvValid = true;
90        return;
91      }
92    }
93    omvValid = false;
94  }
95}
96