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
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
|
/*
* Copyright (c) 2018-2021, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/BitmapView.h>
#include <AK/Noncopyable.h>
#include <AK/Optional.h>
#include <AK/Platform.h>
#include <AK/StdLibExtras.h>
#include <AK/Types.h>
#include <AK/kmalloc.h>
namespace AK {
class Bitmap {
AK_MAKE_NONCOPYABLE(Bitmap);
public:
Bitmap() = default;
Bitmap(size_t size, bool default_value)
: m_size(size)
{
VERIFY(m_size != 0);
m_data = static_cast<u8*>(kmalloc(size_in_bytes()));
fill(default_value);
}
Bitmap(u8* data, size_t size, bool is_owning = false)
: m_data(data)
, m_size(size)
, m_is_owning(is_owning)
{
}
[[nodiscard]] BitmapView view() { return { m_data, m_size }; }
[[nodiscard]] BitmapView const view() const { return { m_data, m_size }; }
Bitmap(Bitmap&& other)
: m_data(exchange(other.m_data, nullptr))
, m_size(exchange(other.m_size, 0))
{
}
Bitmap& operator=(Bitmap&& other)
{
if (this != &other) {
kfree_sized(m_data, size_in_bytes());
m_data = exchange(other.m_data, nullptr);
m_size = exchange(other.m_size, 0);
}
return *this;
}
~Bitmap()
{
if (m_is_owning) {
kfree_sized(m_data, size_in_bytes());
}
m_data = nullptr;
}
[[nodiscard]] size_t size() const { return m_size; }
[[nodiscard]] size_t size_in_bytes() const { return ceil_div(m_size, static_cast<size_t>(8)); }
[[nodiscard]] bool get(size_t index) const
{
VERIFY(index < m_size);
return 0 != (m_data[index / 8] & (1u << (index % 8)));
}
void set(size_t index, bool value)
{
VERIFY(index < m_size);
if (value)
m_data[index / 8] |= static_cast<u8>((1u << (index % 8)));
else
m_data[index / 8] &= static_cast<u8>(~(1u << (index % 8)));
}
[[nodiscard]] size_t count_slow(bool value) const { return count_in_range(0, m_size, value); }
[[nodiscard]] size_t count_in_range(size_t start, size_t len, bool value) const { return view().count_in_range(start, len, value); }
[[nodiscard]] bool is_null() const { return !m_data; }
[[nodiscard]] u8* data() { return m_data; }
[[nodiscard]] u8 const* data() const { return m_data; }
void grow(size_t size, bool default_value)
{
VERIFY(size > m_size);
auto previous_size_bytes = size_in_bytes();
auto previous_size = m_size;
auto previous_data = m_data;
m_size = size;
m_data = reinterpret_cast<u8*>(kmalloc(size_in_bytes()));
fill(default_value);
if (previous_data != nullptr) {
__builtin_memcpy(m_data, previous_data, previous_size_bytes);
if (previous_size % 8)
set_range(previous_size, 8 - previous_size % 8, default_value);
kfree_sized(previous_data, previous_size_bytes);
}
}
template<bool VALUE, bool verify_that_all_bits_flip = false>
void set_range(size_t start, size_t len)
{
VERIFY(start < m_size);
VERIFY(start + len <= m_size);
if (len == 0)
return;
u8* first = &m_data[start / 8];
u8* last = &m_data[(start + len) / 8];
u8 byte_mask = bitmask_first_byte[start % 8];
if (first == last) {
byte_mask &= bitmask_last_byte[(start + len) % 8];
if constexpr (verify_that_all_bits_flip) {
if constexpr (VALUE) {
VERIFY((*first & byte_mask) == 0);
} else {
VERIFY((*first & byte_mask) == byte_mask);
}
}
if constexpr (VALUE)
*first |= byte_mask;
else
*first &= ~byte_mask;
} else {
if constexpr (verify_that_all_bits_flip) {
if constexpr (VALUE) {
VERIFY((*first & byte_mask) == 0);
} else {
VERIFY((*first & byte_mask) == byte_mask);
}
}
if constexpr (VALUE)
*first |= byte_mask;
else
*first &= ~byte_mask;
byte_mask = bitmask_last_byte[(start + len) % 8];
if constexpr (verify_that_all_bits_flip) {
if constexpr (VALUE) {
VERIFY((*last & byte_mask) == 0);
} else {
VERIFY((*last & byte_mask) == byte_mask);
}
}
if constexpr (VALUE)
*last |= byte_mask;
else
*last &= ~byte_mask;
if (++first < last) {
if constexpr (VALUE)
__builtin_memset(first, 0xFF, last - first);
else
__builtin_memset(first, 0x0, last - first);
}
}
}
void set_range(size_t start, size_t len, bool value)
{
if (value)
set_range<true, false>(start, len);
else
set_range<false, false>(start, len);
}
void set_range_and_verify_that_all_bits_flip(size_t start, size_t len, bool value)
{
if (value)
set_range<true, true>(start, len);
else
set_range<false, true>(start, len);
}
void fill(bool value)
{
__builtin_memset(m_data, value ? 0xff : 0x00, size_in_bytes());
}
Optional<size_t> find_one_anywhere_set(size_t hint = 0) const { return view().find_one_anywhere<true>(hint); }
Optional<size_t> find_one_anywhere_unset(size_t hint = 0) const { return view().find_one_anywhere<false>(hint); }
Optional<size_t> find_first_set() const { return view().find_first<true>(); }
Optional<size_t> find_first_unset() const { return view().find_first<false>(); }
Optional<size_t> find_next_range_of_unset_bits(size_t& from, size_t min_length = 1, size_t max_length = max_size) const
{
return view().find_next_range_of_unset_bits(from, min_length, max_length);
}
Optional<size_t> find_longest_range_of_unset_bits(size_t max_length, size_t& found_range_size) const
{
return view().find_longest_range_of_unset_bits(max_length, found_range_size);
}
Optional<size_t> find_first_fit(size_t minimum_length) const { return view().find_first_fit(minimum_length); }
Optional<size_t> find_best_fit(size_t minimum_length) const { return view().find_best_fit(minimum_length); }
static constexpr size_t max_size = 0xffffffff;
private:
u8* m_data { nullptr };
size_t m_size { 0 };
bool m_is_owning { true };
};
}
using AK::Bitmap;
|
