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Linux kernel mirror (for testing)
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linux
1#ifndef _X86_64_BITOPS_H
2#define _X86_64_BITOPS_H
3
4/*
5 * Copyright 1992, Linus Torvalds.
6 */
7
8extern long find_first_zero_bit(const unsigned long *addr, unsigned long size);
9extern long find_next_zero_bit(const unsigned long *addr, long size, long offset);
10extern long find_first_bit(const unsigned long *addr, unsigned long size);
11extern long find_next_bit(const unsigned long *addr, long size, long offset);
12
13/* return index of first bet set in val or max when no bit is set */
14static inline long __scanbit(unsigned long val, unsigned long max)
15{
16 asm("bsfq %1,%0 ; cmovz %2,%0" : "=&r" (val) : "r" (val), "r" (max));
17 return val;
18}
19
20#define find_first_bit(addr,size) \
21((__builtin_constant_p(size) && (size) <= BITS_PER_LONG ? \
22 (__scanbit(*(unsigned long *)addr,(size))) : \
23 find_first_bit(addr,size)))
24
25#define find_next_bit(addr,size,off) \
26((__builtin_constant_p(size) && (size) <= BITS_PER_LONG ? \
27 ((off) + (__scanbit((*(unsigned long *)addr) >> (off),(size)-(off)))) : \
28 find_next_bit(addr,size,off)))
29
30#define find_first_zero_bit(addr,size) \
31((__builtin_constant_p(size) && (size) <= BITS_PER_LONG ? \
32 (__scanbit(~*(unsigned long *)addr,(size))) : \
33 find_first_zero_bit(addr,size)))
34
35#define find_next_zero_bit(addr,size,off) \
36((__builtin_constant_p(size) && (size) <= BITS_PER_LONG ? \
37 ((off)+(__scanbit(~(((*(unsigned long *)addr)) >> (off)),(size)-(off)))) : \
38 find_next_zero_bit(addr,size,off)))
39
40static inline void set_bit_string(unsigned long *bitmap, unsigned long i,
41 int len)
42{
43 unsigned long end = i + len;
44 while (i < end) {
45 __set_bit(i, bitmap);
46 i++;
47 }
48}
49
50/**
51 * ffz - find first zero in word.
52 * @word: The word to search
53 *
54 * Undefined if no zero exists, so code should check against ~0UL first.
55 */
56static inline unsigned long ffz(unsigned long word)
57{
58 __asm__("bsfq %1,%0"
59 :"=r" (word)
60 :"r" (~word));
61 return word;
62}
63
64/**
65 * __ffs - find first bit in word.
66 * @word: The word to search
67 *
68 * Undefined if no bit exists, so code should check against 0 first.
69 */
70static inline unsigned long __ffs(unsigned long word)
71{
72 __asm__("bsfq %1,%0"
73 :"=r" (word)
74 :"rm" (word));
75 return word;
76}
77
78/*
79 * __fls: find last bit set.
80 * @word: The word to search
81 *
82 * Undefined if no zero exists, so code should check against ~0UL first.
83 */
84static inline unsigned long __fls(unsigned long word)
85{
86 __asm__("bsrq %1,%0"
87 :"=r" (word)
88 :"rm" (word));
89 return word;
90}
91
92#ifdef __KERNEL__
93
94#include <asm-generic/bitops/sched.h>
95
96/**
97 * ffs - find first bit set
98 * @x: the word to search
99 *
100 * This is defined the same way as
101 * the libc and compiler builtin ffs routines, therefore
102 * differs in spirit from the above ffz (man ffs).
103 */
104static inline int ffs(int x)
105{
106 int r;
107
108 __asm__("bsfl %1,%0\n\t"
109 "cmovzl %2,%0"
110 : "=r" (r) : "rm" (x), "r" (-1));
111 return r+1;
112}
113
114/**
115 * fls64 - find last bit set in 64 bit word
116 * @x: the word to search
117 *
118 * This is defined the same way as fls.
119 */
120static inline int fls64(__u64 x)
121{
122 if (x == 0)
123 return 0;
124 return __fls(x) + 1;
125}
126
127/**
128 * fls - find last bit set
129 * @x: the word to search
130 *
131 * This is defined the same way as ffs.
132 */
133static inline int fls(int x)
134{
135 int r;
136
137 __asm__("bsrl %1,%0\n\t"
138 "cmovzl %2,%0"
139 : "=&r" (r) : "rm" (x), "rm" (-1));
140 return r+1;
141}
142
143#define ARCH_HAS_FAST_MULTIPLIER 1
144
145#include <asm-generic/bitops/hweight.h>
146
147#endif /* __KERNEL__ */
148
149#ifdef __KERNEL__
150
151#include <asm-generic/bitops/ext2-non-atomic.h>
152
153#define ext2_set_bit_atomic(lock,nr,addr) \
154 test_and_set_bit((nr),(unsigned long*)addr)
155#define ext2_clear_bit_atomic(lock,nr,addr) \
156 test_and_clear_bit((nr),(unsigned long*)addr)
157
158#include <asm-generic/bitops/minix.h>
159
160#endif /* __KERNEL__ */
161
162#endif /* _X86_64_BITOPS_H */