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| author | Samuel Thibault <samuel.thibault@ens-lyon.org> | 2012-02-19 06:14:24 +0000 |
|---|---|---|
| committer | Samuel Thibault <samuel.thibault@ens-lyon.org> | 2012-02-19 06:14:24 +0000 |
| commit | 6fafeb146e9efd59140ea58cebd7dd38ae9a6379 (patch) | |
| tree | 7db89ba6a28932514b105d620bba4884ec332ec3 /libdde_linux26/contrib/include/asm-generic/bitops/ffs.h | |
| parent | 38c2c2458e3f4ecb329ff35621806252aac209b9 (diff) | |
| parent | 8df772b3c665e663f6f9d2a70f9c691590bd3f91 (diff) | |
Merge branch 'dde' into upstream-merged
Diffstat (limited to 'libdde_linux26/contrib/include/asm-generic/bitops/ffs.h')
| -rw-r--r-- | libdde_linux26/contrib/include/asm-generic/bitops/ffs.h | 41 |
1 files changed, 41 insertions, 0 deletions
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_ */ |
