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
|
/* Copyright (C) 2011 Wildfire Games.
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
/*
* FIFO bit queue
*/
#ifndef INCLUDED_ADTS_BIT_BUF
#define INCLUDED_ADTS_BIT_BUF
#include "lib/bits.h"
struct BitBuf
{
uintptr_t buf;
uintptr_t cur; // bit to be appended (toggled by add())
size_t len; // |buf| [bits]
void reset()
{
buf = 0;
cur = 0;
len = 0;
}
// toggle current bit if desired, and add to buffer (new bit is LSB)
void add(uintptr_t toggle)
{
cur ^= toggle;
buf <<= 1;
buf |= cur;
len++;
}
// extract LS n bits
size_t extract(uintptr_t n)
{
const uintptr_t bits = buf & bit_mask<uintptr_t>(n);
buf >>= n;
return bits;
}
};
#endif // #ifndef INCLUDED_ADTS_BIT_BUF
|
