bitops.h

  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