Function _mm256_srai_epi64

#[target_feature(enable = "avx512f", enable = "avx512vl")]
pub const fn _mm256_srai_epi64(a: __m256i, IMM8: u32) -> __m256i

Shift packed 64-bit integers in a right by imm8 while shifting in sign bits, and store the results in dst.

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