Function _mm256_shldi_epi64

#[target_feature(enable = "avx512vbmi2", enable = "avx512vl")]
pub const fn _mm256_shldi_epi64(a: __m256i, b: __m256i, IMM8: i32) -> __m256i

Concatenate packed 64-bit integers in a and b producing an intermediate 128-bit result. Shift the result left by imm8 bits, and store the upper 64-bits in dst).

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