pub unsafe fn _mm256_testn_epi64_mask(a: __m256i, b: __m256i) -> __mmask8
🔬 This is a nightly-only experimental API. (stdsimd #48556)
Available on x86 and target feature avx512f,avx512vl only.
Expand description

Compute the bitwise NAND of packed 64-bit integers in a and b, producing intermediate 64-bit values, and set the corresponding bit in result mask k if the intermediate value is zero.

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