From 8a6d48c0542876eb3acfc0970c0ab7872db08d5f Mon Sep 17 00:00:00 2001 From: Zheng Da Date: Sun, 6 Dec 2009 05:26:23 +0100 Subject: check in the original version of dde linux26. --- .../contrib/include/asm-generic/bitops/ffs.h | 41 ++++++++++++++++++++++ 1 file changed, 41 insertions(+) create mode 100644 libdde_linux26/contrib/include/asm-generic/bitops/ffs.h (limited to 'libdde_linux26/contrib/include/asm-generic/bitops/ffs.h') diff --git a/libdde_linux26/contrib/include/asm-generic/bitops/ffs.h b/libdde_linux26/contrib/include/asm-generic/bitops/ffs.h new file mode 100644 index 00000000..fbbb43af --- /dev/null +++ b/libdde_linux26/contrib/include/asm-generic/bitops/ffs.h @@ -0,0 +1,41 @@ +#ifndef _ASM_GENERIC_BITOPS_FFS_H_ +#define _ASM_GENERIC_BITOPS_FFS_H_ + +/** + * 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 the above ffz (man ffs). + */ +static inline int 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; +} + +#endif /* _ASM_GENERIC_BITOPS_FFS_H_ */ -- cgit v1.2.3