Function _mm_maskz_alignr_epi64

#[target_feature(enable = "avx512f", enable = "avx512vl")]
pub const fn _mm_maskz_alignr_epi64(k: __mmask8, a: __m128i, b: __m128i, IMM8: i32) -> __m128i

Concatenate a and b into a 32-byte immediate result, shift the result right by imm8 64-bit elements, and store the low 16 bytes (2 elements) in dst using zeromask k (elements are zeroed out when the corresponding mask bit is not set).

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