pub unsafe fn _mm_mask_sllv_epi64(
    src: __m128i,
    k: __mmask8,
    a: __m128i,
    count: __m128i
) -> __m128i
🔬 This is a nightly-only experimental API. (stdsimd #48556)
This is supported on x86 and target feature avx512f,avx512vl only.
Expand description

Shift packed 64-bit integers in a left by the amount specified by the corresponding element in count while shifting in zeros, 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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