[PATCH v3 26/31] arm64: Miscellaneous library functions
Arnd Bergmann
arnd at arndb.de
Fri Sep 7 15:52:13 EDT 2012
On Friday 07 September 2012, Catalin Marinas wrote:
> +/*
> + * Use compiler builtins for simple inline operations.
> + */
> +static inline unsigned long __ffs(unsigned long word)
> +{
> + return __builtin_ffsl(word) - 1;
> +}
> +
> +static inline int ffs(int x)
> +{
> + return __builtin_ffs(x);
> +}
> +
> +static inline unsigned long __fls(unsigned long word)
> +{
> + return BITS_PER_LONG - 1 - __builtin_clzl(word);
> +}
> +
> +static inline int fls(int x)
> +{
> + return x ? sizeof(x) * BITS_PER_BYTE - __builtin_clz(x) : 0;
> +}
Still waiting for the generic version of these.
Arnd
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