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 (644B)

      1/* SPDX-License-Identifier: GPL-2.0 */
      2#ifndef _ASM_GENERIC_BITOPS_FFS_H_
      3#define _ASM_GENERIC_BITOPS_FFS_H_
      4
      5/**
      6 * ffs - find first bit set
      7 * @x: the word to search
      8 *
      9 * This is defined the same way as
     10 * the libc and compiler builtin ffs routines, therefore
     11 * differs in spirit from ffz (man ffs).
     12 */
     13static inline int ffs(int x)
     14{
     15	int r = 1;
     16
     17	if (!x)
     18		return 0;
     19	if (!(x & 0xffff)) {
     20		x >>= 16;
     21		r += 16;
     22	}
     23	if (!(x & 0xff)) {
     24		x >>= 8;
     25		r += 8;
     26	}
     27	if (!(x & 0xf)) {
     28		x >>= 4;
     29		r += 4;
     30	}
     31	if (!(x & 3)) {
     32		x >>= 2;
     33		r += 2;
     34	}
     35	if (!(x & 1)) {
     36		x >>= 1;
     37		r += 1;
     38	}
     39	return r;
     40}
     41
     42#endif /* _ASM_GENERIC_BITOPS_FFS_H_ */