[FFmpeg-devel] [PATCH 1/3] common: add ff_parity()

[Clément Bœsch]

On Sun, Jan 03, 2016 at 08:21:00PM +0100, Clément Bœsch wrote:
[...]
> +static av_always_inline av_const int ff_parity(uint32_t v)
> +{
> +#if HAVE_PARITY
> +    return __builtin_parity(v);
> +#else
> +    return av_popcount(v) & 1;

doing a popcount being overkill, this could be replaced with
(0x6996966996696996ULL >> (x & 63) ^ (x>>7) ^ (x>>6)) & 1

Whatever people prefers

-- 
Clément B.
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