pub unsafe fn _mm256_mask_shrdi_epi64<const IMM8: i32>(
    src: __m256i,
    k: u8,
    a: __m256i,
    b: __m256i
) -> __m256i
🔬 This is a nightly-only experimental API. (stdsimd)
This is supported on x86-64 and target feature avx512vbmi2,avx512vl only.
Expand description

Concatenate packed 64-bit integers in b and a producing an intermediate 128-bit result. Shift the result right by imm8 bits, and store the lower 64-bits in dst using writemask k (elements are copied from src“ when the corresponding mask bit is not set).

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