summaryrefslogtreecommitdiff
path: root/js/src/jit/BitSet.cpp
blob: 6171a1b174918ea07232efae2884a9be9dfcc94f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
 * vim: set ts=8 sts=4 et sw=4 tw=99:
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "jit/BitSet.h"

using namespace js;
using namespace js::jit;

bool
BitSet::init(TempAllocator& alloc)
{
    size_t sizeRequired = numWords() * sizeof(*bits_);

    bits_ = (uint32_t*)alloc.allocate(sizeRequired);
    if (!bits_)
        return false;

    memset(bits_, 0, sizeRequired);

    return true;
}

bool
BitSet::empty() const
{
    MOZ_ASSERT(bits_);
    const uint32_t* bits = bits_;
    for (unsigned int i = 0, e = numWords(); i < e; i++) {
        if (bits[i])
            return false;
    }
    return true;
}

void
BitSet::insertAll(const BitSet& other)
{
    MOZ_ASSERT(bits_);
    MOZ_ASSERT(other.numBits_ == numBits_);
    MOZ_ASSERT(other.bits_);

    uint32_t* bits = bits_;
    const uint32_t* otherBits = other.bits_;
    for (unsigned int i = 0, e = numWords(); i < e; i++)
        bits[i] |= otherBits[i];
}

void
BitSet::removeAll(const BitSet& other)
{
    MOZ_ASSERT(bits_);
    MOZ_ASSERT(other.numBits_ == numBits_);
    MOZ_ASSERT(other.bits_);

    uint32_t* bits = bits_;
    const uint32_t* otherBits = other.bits_;
    for (unsigned int i = 0, e = numWords(); i < e; i++)
        bits[i] &= ~otherBits[i];
}

void
BitSet::intersect(const BitSet& other)
{
    MOZ_ASSERT(bits_);
    MOZ_ASSERT(other.numBits_ == numBits_);
    MOZ_ASSERT(other.bits_);

    uint32_t* bits = bits_;
    const uint32_t* otherBits = other.bits_;
    for (unsigned int i = 0, e = numWords(); i < e; i++)
        bits[i] &= otherBits[i];
}

// returns true if the intersection caused the contents of the set to change.
bool
BitSet::fixedPointIntersect(const BitSet& other)
{
    MOZ_ASSERT(bits_);
    MOZ_ASSERT(other.numBits_ == numBits_);
    MOZ_ASSERT(other.bits_);

    bool changed = false;

    uint32_t* bits = bits_;
    const uint32_t* otherBits = other.bits_;
    for (unsigned int i = 0, e = numWords(); i < e; i++) {
        uint32_t old = bits[i];
        bits[i] &= otherBits[i];

        if (!changed && old != bits[i])
            changed = true;
    }
    return changed;
}

void
BitSet::complement()
{
    MOZ_ASSERT(bits_);
    uint32_t* bits = bits_;
    for (unsigned int i = 0, e = numWords(); i < e; i++)
        bits[i] = ~bits[i];
}

void
BitSet::clear()
{
    MOZ_ASSERT(bits_);
    uint32_t* bits = bits_;
    for (unsigned int i = 0, e = numWords(); i < e; i++)
        bits[i] = 0;
}