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    Subject[ 51/55] tile: fix bug where fls(0) was not returning 0
    3.0-stable review patch.  If anyone has any objections, please let me know.

    ------------------

    From: Chris Metcalf <cmetcalf@tilera.com>

    commit 9f1d62bed7f015d11b9164078b7fea433b474114 upstream.

    This is because __builtin_clz(0) returns 64 for the "undefined" case
    of 0, since the builtin just does a right-shift 32 and "clz" instruction.
    So, use the alpha approach of casting to u32 and using __builtin_clzll().

    Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
    Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

    ---
    arch/tile/include/asm/bitops.h | 12 ++++++------
    1 file changed, 6 insertions(+), 6 deletions(-)

    --- a/arch/tile/include/asm/bitops.h
    +++ b/arch/tile/include/asm/bitops.h
    @@ -77,6 +77,11 @@ static inline int ffs(int x)
    return __builtin_ffs(x);
    }

    +static inline int fls64(__u64 w)
    +{
    + return (sizeof(__u64) * 8) - __builtin_clzll(w);
    +}
    +
    /**
    * fls - find last set bit in word
    * @x: the word to search
    @@ -90,12 +95,7 @@ static inline int ffs(int x)
    */
    static inline int fls(int x)
    {
    - return (sizeof(int) * 8) - __builtin_clz(x);
    -}
    -
    -static inline int fls64(__u64 w)
    -{
    - return (sizeof(__u64) * 8) - __builtin_clzll(w);
    + return fls64((unsigned int) x);
    }

    static inline unsigned int __arch_hweight32(unsigned int w)



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