Function _mm_mask_lzcnt_epi64

#[target_feature(enable = "avx512cd", enable = "avx512vl")]
pub const fn _mm_mask_lzcnt_epi64(src: __m128i, k: __mmask8, a: __m128i) -> __m128i

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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