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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