diff options
Diffstat (limited to 'include')
-rw-r--r-- | include/linux/bitops.h | 124 |
1 files changed, 1 insertions, 123 deletions
diff --git a/include/linux/bitops.h b/include/linux/bitops.h index f17525a963d1..5d1eabcde5d5 100644 --- a/include/linux/bitops.h +++ b/include/linux/bitops.h | |||
@@ -3,88 +3,11 @@ | |||
3 | #include <asm/types.h> | 3 | #include <asm/types.h> |
4 | 4 | ||
5 | /* | 5 | /* |
6 | * ffs: find first bit set. This is defined the same way as | ||
7 | * the libc and compiler builtin ffs routines, therefore | ||
8 | * differs in spirit from the above ffz (man ffs). | ||
9 | */ | ||
10 | |||
11 | static inline int generic_ffs(int x) | ||
12 | { | ||
13 | int r = 1; | ||
14 | |||
15 | if (!x) | ||
16 | return 0; | ||
17 | if (!(x & 0xffff)) { | ||
18 | x >>= 16; | ||
19 | r += 16; | ||
20 | } | ||
21 | if (!(x & 0xff)) { | ||
22 | x >>= 8; | ||
23 | r += 8; | ||
24 | } | ||
25 | if (!(x & 0xf)) { | ||
26 | x >>= 4; | ||
27 | r += 4; | ||
28 | } | ||
29 | if (!(x & 3)) { | ||
30 | x >>= 2; | ||
31 | r += 2; | ||
32 | } | ||
33 | if (!(x & 1)) { | ||
34 | x >>= 1; | ||
35 | r += 1; | ||
36 | } | ||
37 | return r; | ||
38 | } | ||
39 | |||
40 | /* | ||
41 | * fls: find last bit set. | ||
42 | */ | ||
43 | |||
44 | static __inline__ int generic_fls(int x) | ||
45 | { | ||
46 | int r = 32; | ||
47 | |||
48 | if (!x) | ||
49 | return 0; | ||
50 | if (!(x & 0xffff0000u)) { | ||
51 | x <<= 16; | ||
52 | r -= 16; | ||
53 | } | ||
54 | if (!(x & 0xff000000u)) { | ||
55 | x <<= 8; | ||
56 | r -= 8; | ||
57 | } | ||
58 | if (!(x & 0xf0000000u)) { | ||
59 | x <<= 4; | ||
60 | r -= 4; | ||
61 | } | ||
62 | if (!(x & 0xc0000000u)) { | ||
63 | x <<= 2; | ||
64 | r -= 2; | ||
65 | } | ||
66 | if (!(x & 0x80000000u)) { | ||
67 | x <<= 1; | ||
68 | r -= 1; | ||
69 | } | ||
70 | return r; | ||
71 | } | ||
72 | |||
73 | /* | ||
74 | * Include this here because some architectures need generic_ffs/fls in | 6 | * Include this here because some architectures need generic_ffs/fls in |
75 | * scope | 7 | * scope |
76 | */ | 8 | */ |
77 | #include <asm/bitops.h> | 9 | #include <asm/bitops.h> |
78 | 10 | ||
79 | |||
80 | static inline int generic_fls64(__u64 x) | ||
81 | { | ||
82 | __u32 h = x >> 32; | ||
83 | if (h) | ||
84 | return fls(h) + 32; | ||
85 | return fls(x); | ||
86 | } | ||
87 | |||
88 | static __inline__ int get_bitmask_order(unsigned int count) | 11 | static __inline__ int get_bitmask_order(unsigned int count) |
89 | { | 12 | { |
90 | int order; | 13 | int order; |
@@ -103,54 +26,9 @@ static __inline__ int get_count_order(unsigned int count) | |||
103 | return order; | 26 | return order; |
104 | } | 27 | } |
105 | 28 | ||
106 | /* | ||
107 | * hweightN: returns the hamming weight (i.e. the number | ||
108 | * of bits set) of a N-bit word | ||
109 | */ | ||
110 | |||
111 | static inline unsigned int generic_hweight32(unsigned int w) | ||
112 | { | ||
113 | unsigned int res = (w & 0x55555555) + ((w >> 1) & 0x55555555); | ||
114 | res = (res & 0x33333333) + ((res >> 2) & 0x33333333); | ||
115 | res = (res & 0x0F0F0F0F) + ((res >> 4) & 0x0F0F0F0F); | ||
116 | res = (res & 0x00FF00FF) + ((res >> 8) & 0x00FF00FF); | ||
117 | return (res & 0x0000FFFF) + ((res >> 16) & 0x0000FFFF); | ||
118 | } | ||
119 | |||
120 | static inline unsigned int generic_hweight16(unsigned int w) | ||
121 | { | ||
122 | unsigned int res = (w & 0x5555) + ((w >> 1) & 0x5555); | ||
123 | res = (res & 0x3333) + ((res >> 2) & 0x3333); | ||
124 | res = (res & 0x0F0F) + ((res >> 4) & 0x0F0F); | ||
125 | return (res & 0x00FF) + ((res >> 8) & 0x00FF); | ||
126 | } | ||
127 | |||
128 | static inline unsigned int generic_hweight8(unsigned int w) | ||
129 | { | ||
130 | unsigned int res = (w & 0x55) + ((w >> 1) & 0x55); | ||
131 | res = (res & 0x33) + ((res >> 2) & 0x33); | ||
132 | return (res & 0x0F) + ((res >> 4) & 0x0F); | ||
133 | } | ||
134 | |||
135 | static inline unsigned long generic_hweight64(__u64 w) | ||
136 | { | ||
137 | #if BITS_PER_LONG < 64 | ||
138 | return generic_hweight32((unsigned int)(w >> 32)) + | ||
139 | generic_hweight32((unsigned int)w); | ||
140 | #else | ||
141 | u64 res; | ||
142 | res = (w & 0x5555555555555555ul) + ((w >> 1) & 0x5555555555555555ul); | ||
143 | res = (res & 0x3333333333333333ul) + ((res >> 2) & 0x3333333333333333ul); | ||
144 | res = (res & 0x0F0F0F0F0F0F0F0Ful) + ((res >> 4) & 0x0F0F0F0F0F0F0F0Ful); | ||
145 | res = (res & 0x00FF00FF00FF00FFul) + ((res >> 8) & 0x00FF00FF00FF00FFul); | ||
146 | res = (res & 0x0000FFFF0000FFFFul) + ((res >> 16) & 0x0000FFFF0000FFFFul); | ||
147 | return (res & 0x00000000FFFFFFFFul) + ((res >> 32) & 0x00000000FFFFFFFFul); | ||
148 | #endif | ||
149 | } | ||
150 | |||
151 | static inline unsigned long hweight_long(unsigned long w) | 29 | static inline unsigned long hweight_long(unsigned long w) |
152 | { | 30 | { |
153 | return sizeof(w) == 4 ? generic_hweight32(w) : generic_hweight64(w); | 31 | return sizeof(w) == 4 ? hweight32(w) : hweight64(w); |
154 | } | 32 | } |
155 | 33 | ||
156 | /* | 34 | /* |