pub unsafe fn _mm_mask_shldv_epi64(
    a: __m128i,
    k: __mmask8,
    b: __m128i,
    c: __m128i
) -> __m128i
🔬 This is a nightly-only experimental API. (stdsimd #48556)
Available on x86 and target feature avx512vbmi2,avx512vl only.
Expand description

Concatenate packed 64-bit integers in a and b producing an intermediate 128-bit result. Shift the result left by the amount specified in the corresponding element of c, and store the upper 64-bits in dst using writemask k (elements are copied from a when the corresponding mask bit is not set).

Intel’s documentation