pub unsafe fn _mm_mask_lzcnt_epi64(
    src: __m128i,
    k: __mmask8,
    a: __m128i
) -> __m128i
🔬This is a nightly-only experimental API. (stdsimd #48556)
Available on (x86 or x86-64) and target feature avx512cd,avx512vl only.
Expand description

Counts the number of leading zero bits in each packed 64-bit integer in a, and store the results in dst using writemask k (elements are copied from src when the corresponding mask bit is not set).

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