cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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__ffs.h (777B)

      1/* SPDX-License-Identifier: GPL-2.0 */
      2#ifndef _ASM_GENERIC_BITOPS___FFS_H_
      3#define _ASM_GENERIC_BITOPS___FFS_H_
      4
      5#include <asm/types.h>
      6
      7/**
      8 * __ffs - find first bit in word.
      9 * @word: The word to search
     10 *
     11 * Undefined if no bit exists, so code should check against 0 first.
     12 */
     13static __always_inline unsigned long __ffs(unsigned long word)
     14{
     15	int num = 0;
     16
     17#if BITS_PER_LONG == 64
     18	if ((word & 0xffffffff) == 0) {
     19		num += 32;
     20		word >>= 32;
     21	}
     22#endif
     23	if ((word & 0xffff) == 0) {
     24		num += 16;
     25		word >>= 16;
     26	}
     27	if ((word & 0xff) == 0) {
     28		num += 8;
     29		word >>= 8;
     30	}
     31	if ((word & 0xf) == 0) {
     32		num += 4;
     33		word >>= 4;
     34	}
     35	if ((word & 0x3) == 0) {
     36		num += 2;
     37		word >>= 2;
     38	}
     39	if ((word & 0x1) == 0)
     40		num += 1;
     41	return num;
     42}
     43
     44#endif /* _ASM_GENERIC_BITOPS___FFS_H_ */