Function _ktestz_mask64_u8

#[target_feature(enable = "avx512bw")]
pub const fn _ktestz_mask64_u8(a: __mmask64, b: __mmask64) -> u8

Compute the bitwise AND of 64-bit masks a and b, if the result is all zeros, store 1 in dst, otherwise store 0 in dst.

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