Linux kernel mirror (for testing)
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linux
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _TOOLS_LINUX_BITOPS_H_
3#define _TOOLS_LINUX_BITOPS_H_
4
5#include <asm/types.h>
6#include <limits.h>
7#ifndef __WORDSIZE
8#define __WORDSIZE (__SIZEOF_LONG__ * 8)
9#endif
10
11#ifndef BITS_PER_LONG
12# define BITS_PER_LONG __WORDSIZE
13#endif
14#include <linux/bits.h>
15#include <linux/compiler.h>
16
17#define BITS_PER_TYPE(type) (sizeof(type) * BITS_PER_BYTE)
18#define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_TYPE(long))
19#define BITS_TO_U64(nr) DIV_ROUND_UP(nr, BITS_PER_TYPE(u64))
20#define BITS_TO_U32(nr) DIV_ROUND_UP(nr, BITS_PER_TYPE(u32))
21#define BITS_TO_BYTES(nr) DIV_ROUND_UP(nr, BITS_PER_TYPE(char))
22
23#define BYTES_TO_BITS(nb) ((nb) * BITS_PER_BYTE)
24
25extern unsigned int __sw_hweight8(unsigned int w);
26extern unsigned int __sw_hweight16(unsigned int w);
27extern unsigned int __sw_hweight32(unsigned int w);
28extern unsigned long __sw_hweight64(__u64 w);
29
30/*
31 * Defined here because those may be needed by architecture-specific static
32 * inlines.
33 */
34
35#define bitop(op, nr, addr) \
36 op(nr, addr)
37
38#define __set_bit(nr, addr) bitop(___set_bit, nr, addr)
39#define __clear_bit(nr, addr) bitop(___clear_bit, nr, addr)
40#define __change_bit(nr, addr) bitop(___change_bit, nr, addr)
41#define __test_and_set_bit(nr, addr) bitop(___test_and_set_bit, nr, addr)
42#define __test_and_clear_bit(nr, addr) bitop(___test_and_clear_bit, nr, addr)
43#define __test_and_change_bit(nr, addr) bitop(___test_and_change_bit, nr, addr)
44#define test_bit(nr, addr) bitop(_test_bit, nr, addr)
45
46/*
47 * Include this here because some architectures need generic_ffs/fls in
48 * scope
49 *
50 * XXX: this needs to be asm/bitops.h, when we get to per arch optimizations
51 */
52#include <asm-generic/bitops.h>
53
54#define for_each_set_bit(bit, addr, size) \
55 for ((bit) = find_first_bit((addr), (size)); \
56 (bit) < (size); \
57 (bit) = find_next_bit((addr), (size), (bit) + 1))
58
59#define for_each_clear_bit(bit, addr, size) \
60 for ((bit) = find_first_zero_bit((addr), (size)); \
61 (bit) < (size); \
62 (bit) = find_next_zero_bit((addr), (size), (bit) + 1))
63
64/* same as for_each_set_bit() but use bit as value to start with */
65#define for_each_set_bit_from(bit, addr, size) \
66 for ((bit) = find_next_bit((addr), (size), (bit)); \
67 (bit) < (size); \
68 (bit) = find_next_bit((addr), (size), (bit) + 1))
69
70static inline unsigned long hweight_long(unsigned long w)
71{
72 return sizeof(w) == 4 ? hweight32(w) : hweight64(w);
73}
74
75static inline unsigned int fls_long(unsigned long l)
76{
77 if (sizeof(l) == 4)
78 return fls(l);
79 return fls64(l);
80}
81
82/**
83 * rol32 - rotate a 32-bit value left
84 * @word: value to rotate
85 * @shift: bits to roll
86 */
87static inline __u32 rol32(__u32 word, unsigned int shift)
88{
89 return (word << shift) | (word >> ((-shift) & 31));
90}
91
92/**
93 * sign_extend64 - sign extend a 64-bit value using specified bit as sign-bit
94 * @value: value to sign extend
95 * @index: 0 based bit index (0<=index<64) to sign bit
96 */
97static __always_inline __s64 sign_extend64(__u64 value, int index)
98{
99 __u8 shift = 63 - index;
100 return (__s64)(value << shift) >> shift;
101}
102
103#endif