1 /* ----------------------------------------------------------------------- *
2 *
3 * Copyright 2010-2011 Intel Corporation; author: H. Peter Anvin
4 *
5 * Permission is hereby granted, free of charge, to any person
6 * obtaining a copy of this software and associated documentation
7 * files (the "Software"), to deal in the Software without
8 * restriction, including without limitation the rights to use,
9 * copy, modify, merge, publish, distribute, sublicense, and/or
10 * sell copies of the Software, and to permit persons to whom
11 * the Software is furnished to do so, subject to the following
12 * conditions:
13 *
14 * The above copyright notice and this permission notice shall
15 * be included in all copies or substantial portions of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
18 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
19 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
20 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
21 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
22 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
23 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
24 * OTHER DEALINGS IN THE SOFTWARE.
25 *
26 * ----------------------------------------------------------------------- */
27
28 /*
29 * bitops.h - i386
30 *
31 * Simple bitwise operations
32 */
33
set_bit(long __bit,void * __bitmap)34 static inline void set_bit(long __bit, void *__bitmap)
35 {
36 asm volatile("bts %1,%0"
37 : "+m" (*(unsigned char *)__bitmap)
38 : "Ir" (__bit) : "memory");
39 }
40
clr_bit(long __bit,void * __bitmap)41 static inline void clr_bit(long __bit, void *__bitmap)
42 {
43 asm volatile("btcl %1,%0"
44 : "+m" (*(unsigned char *)__bitmap)
45 : "Ir" (__bit) : "memory");
46 }
47
test_bit(long __bit,const void * __bitmap)48 static inline int __purefunc test_bit(long __bit, const void *__bitmap)
49 {
50 unsigned char __r;
51 asm("bt %2,%1; setc %0"
52 : "=qm" (__r)
53 : "m" (*(const unsigned char *)__bitmap), "Ir" (__bit));
54 return __r;
55 }
56