/* SPDX-License-Identifier: GPL-2.0 */ #ifndef _ASM_GENERIC_BITOPS_FFS_H_ #define _ASM_GENERIC_BITOPS_FFS_H_ /** * generic_ffs - find first bit set * @x: the word to search * * This is defined the same way as * the libc and compiler builtin ffs routines, therefore * differs in spirit from ffz (man ffs). */ static inline int generic_ffs(int x) { int r = 1; if (!x) return 0; if (!(x & 0xffff)) { x >>= 16; r += 16; } if (!(x & 0xff)) { x >>= 8; r += 8; } if (!(x & 0xf)) { x >>= 4; r += 4; } if (!(x & 3)) { x >>= 2; r += 2; } if (!(x & 1)) { x >>= 1; r += 1; } return r; } #ifndef __HAVE_ARCH_FFS #define ffs(x) generic_ffs(x) #endif #endif /* _ASM_GENERIC_BITOPS_FFS_H_ */