# Function core::arch::x86::_mm512_mask_lzcnt_epi64

source ·

    pub unsafe fn _mm512_mask_lzcnt_epi64(
        src: __m512i,
        k: __mmask8,
        a: __m512i,
    ) -> __m512i

🔬This is a nightly-only experimental API. (`stdarch_x86_avx512` #111137)
Available on (x86 or x86-64) and target feature `avx512cd` and x86 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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