File: pack_bits.cpp

package info (click to toggle)
vectorscan 5.4.11-2
  • links: PTS, VCS
  • area: main
  • in suites: forky, sid, trixie
  • size: 12,864 kB
  • sloc: cpp: 150,782; ansic: 40,288; python: 620; sh: 32; makefile: 14
file content (161 lines) | stat: -rw-r--r-- 5,231 bytes parent folder | download | duplicates (2)
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
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
/*
 * Copyright (c) 2015, Intel Corporation
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *  * Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 *  * Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *  * Neither the name of Intel Corporation nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include "config.h"

#include "gtest/gtest.h"
#include "util/pack_bits.h"
#include "ue2common.h"

#include <algorithm>
#include <memory>
#include <vector>

using std::unique_ptr;
using std::vector;

template <typename T>
class PackBits : public testing::Test {};

typedef ::testing::Types<u32, u64a> PackBitsTypes;
TYPED_TEST_CASE(PackBits, PackBitsTypes);

// Templated wrappers around the pack_bits_{32,64} functions.
template <typename T>
void pack_bits(char *out, const T *v, const u32 *bits, unsigned elements);
template <typename T>
void unpack_bits(T *v, const char *in, const u32 *bits, unsigned elements);

template <>
void pack_bits<u32>(char *out, const u32 *v, const u32 *bits,
                    unsigned elements) {
    return pack_bits_32(out, v, bits, elements);
}

template <>
void pack_bits<u64a>(char *out, const u64a *v, const u32 *bits,
                     unsigned elements) {
    return pack_bits_64(out, v, bits, elements);
}

template <>
void unpack_bits<u32>(u32 *v, const char *in, const u32 *bits,
                      unsigned elements) {
    return unpack_bits_32(v, (const u8 *)in, bits, elements);
}

template <>
void unpack_bits<u64a>(u64a *v, const char *in, const u32 *bits,
                       unsigned elements) {
    return unpack_bits_64(v, (const u8 *)in, bits, elements);
}

template <typename T>
size_t packed_size(const vector<T> &bits) {
    size_t num_bits = 0;
    for (size_t i = 0; i < bits.size(); i++) {
        num_bits += bits[i];
    }
    return ROUNDUP_N(num_bits, 8U) / 8U;
}

template <typename T>
void test_pack_and_unpack(const vector<T> &v, const vector<u32> &bits) {
    const u32 max_bits = sizeof(T) * 8U;
    const u32 elements = bits.size();

    // Temporary char array to pack into.
    const size_t mem_size = packed_size(bits);
    unique_ptr<char[]> mem = std::make_unique<char[]>(mem_size);

    pack_bits<T>(&mem[0], &v[0], &bits[0], elements);

    vector<T> v2(elements, 0xcafecafeu); // Output vector.

    unpack_bits<T>(&v2[0], &mem[0], &bits[0], elements);

    for (u32 i = 0; i < elements; i++) {
        // Check that v2[i] contains the bits[i] low bits of v[i].
        T mask = bits[i] == max_bits ? ~(T)0 : ((T)1U << bits[i]) - 1;
        ASSERT_EQ(v[i] & mask, v2[i]) << "element " << i << " mismatch";
    }
}

TYPED_TEST(PackBits, AllZeroes) {
    for (u32 i = 1; i < 32; i++) {
        SCOPED_TRACE(i);
        vector<TypeParam> v(i, 0);
        vector<u32> bits(i, sizeof(TypeParam) * 8U); // all bits
        test_pack_and_unpack(v, bits);
    }
}

TYPED_TEST(PackBits, AllOnes) {
    for (u32 i = 1; i < 32; i++) {
        SCOPED_TRACE(i);
        vector<TypeParam> v(i, ~((TypeParam)0));

        for (u32 num_bits = 0; num_bits < sizeof(TypeParam) * 8U; num_bits++) {
            vector<u32> bits(i, num_bits);
            test_pack_and_unpack(v, bits);
        }
    }
}

TYPED_TEST(PackBits, SomeOnes) {
    for (u32 i = 1; i < 32; i++) {
        SCOPED_TRACE(i);
        vector<TypeParam> v(i, ~((TypeParam)0));

        // One bit from v[0], two bits from v[1] ...
        vector<u32> bits(i);
        for (u32 j = 0; j < i; j++) {
        }

        test_pack_and_unpack(v, bits);

        // And in reverse
        std::reverse(bits.begin(), bits.end());
        test_pack_and_unpack(v, bits);
    }
}

TYPED_TEST(PackBits, Holes) {
    for (u32 i = 1; i < 32; i++) {
        SCOPED_TRACE(i);
        vector<TypeParam> v(i, ~((TypeParam)0));

        // No bits from odd-numbered words.
        vector<u32> bits(i);
        for (u32 j = 0; j < i; j++) {
            bits[j] = j % 2 ? 0 : sizeof(TypeParam) * 8U;
        }

        test_pack_and_unpack(v, bits);
    }
}