1/*
2 * Copyright (C) 2011 Apple Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
14 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
15 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
17 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
18 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
19 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
20 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
21 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
22 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
23 * THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#ifndef TinyBloomFilter_h
27#define TinyBloomFilter_h
28
29namespace JSC {
30
31typedef uintptr_t Bits;
32
33class TinyBloomFilter {
34public:
35 TinyBloomFilter();
36
37 void add(Bits);
38 void add(TinyBloomFilter&);
39 bool ruleOut(Bits) const; // True for 0.
40 void reset();
41
42private:
43 Bits m_bits;
44};
45
46inline TinyBloomFilter::TinyBloomFilter()
47 : m_bits(0)
48{
49}
50
51inline void TinyBloomFilter::add(Bits bits)
52{
53 m_bits |= bits;
54}
55
56inline void TinyBloomFilter::add(TinyBloomFilter& other)
57{
58 m_bits |= other.m_bits;
59}
60
61inline bool TinyBloomFilter::ruleOut(Bits bits) const
62{
63 if (!bits)
64 return true;
65
66 if ((bits & m_bits) != bits)
67 return true;
68
69 return false;
70}
71
72inline void TinyBloomFilter::reset()
73{
74 m_bits = 0;
75}
76
77} // namespace JSC
78
79#endif // TinyBloomFilter_h
80