linux/tools/include/linux/bitops.h
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   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
  23extern unsigned int __sw_hweight8(unsigned int w);
  24extern unsigned int __sw_hweight16(unsigned int w);
  25extern unsigned int __sw_hweight32(unsigned int w);
  26extern unsigned long __sw_hweight64(__u64 w);
  27
  28/*
  29 * Include this here because some architectures need generic_ffs/fls in
  30 * scope
  31 *
  32 * XXX: this needs to be asm/bitops.h, when we get to per arch optimizations
  33 */
  34#include <asm-generic/bitops.h>
  35
  36#define for_each_set_bit(bit, addr, size) \
  37        for ((bit) = find_first_bit((addr), (size));            \
  38             (bit) < (size);                                    \
  39             (bit) = find_next_bit((addr), (size), (bit) + 1))
  40
  41#define for_each_clear_bit(bit, addr, size) \
  42        for ((bit) = find_first_zero_bit((addr), (size));       \
  43             (bit) < (size);                                    \
  44             (bit) = find_next_zero_bit((addr), (size), (bit) + 1))
  45
  46/* same as for_each_set_bit() but use bit as value to start with */
  47#define for_each_set_bit_from(bit, addr, size) \
  48        for ((bit) = find_next_bit((addr), (size), (bit));      \
  49             (bit) < (size);                                    \
  50             (bit) = find_next_bit((addr), (size), (bit) + 1))
  51
  52static inline unsigned long hweight_long(unsigned long w)
  53{
  54        return sizeof(w) == 4 ? hweight32(w) : hweight64(w);
  55}
  56
  57static inline unsigned fls_long(unsigned long l)
  58{
  59        if (sizeof(l) == 4)
  60                return fls(l);
  61        return fls64(l);
  62}
  63
  64/**
  65 * rol32 - rotate a 32-bit value left
  66 * @word: value to rotate
  67 * @shift: bits to roll
  68 */
  69static inline __u32 rol32(__u32 word, unsigned int shift)
  70{
  71        return (word << shift) | (word >> ((-shift) & 31));
  72}
  73
  74#endif
  75