pub unsafe fn _mm512_mask_lzcnt_epi64(
    src: __m512i,
    k: u8,
    a: __m512i
) -> __m512i
🔬This is a nightly-only experimental API. (stdsimd)
Available on x86-64 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).

Intel’s documentation