[PATCH 2/2] eal: add rte ffs32 and rte ffs64 inline functions

[David Marchand]

On Wed, Mar 20, 2024 at 10:25 PM Tyler Retzlaff
<roretzla at linux.microsoft.com> wrote:
>
> provide toolchain abstraction for __builtin_ffs{,l,ll} gcc built-in
> intrinsics.
>
> Signed-off-by: Tyler Retzlaff <roretzla at linux.microsoft.com>

Please add a unit test and an entry in the release notes.

> ---
>  lib/eal/include/rte_bitops.h | 34 ++++++++++++++++++++++++++++++++++
>  1 file changed, 34 insertions(+)
>
> diff --git a/lib/eal/include/rte_bitops.h b/lib/eal/include/rte_bitops.h
> index 449565e..e157a45 100644
> --- a/lib/eal/include/rte_bitops.h
> +++ b/lib/eal/include/rte_bitops.h
> @@ -405,6 +405,28 @@
>         return (unsigned int)__popcnt64(v);
>  }
>
> +static inline unsigned int
> +rte_ffs32(uint32_t v)
> +{
> +       unsigned long rv;
> +
> +       if (0 == _BitScanForward(&rv, v))

_BitScanForward(&rv, v) == 0 please.


-- 
David Marchand