Function _mm_mask_max_sd

#[target_feature(enable = "avx512f")]
pub fn _mm_mask_max_sd(src: __m128d, k: __mmask8, a: __m128d, b: __m128d) -> __m128d

Compare the lower double-precision (64-bit) floating-point elements in a and b, store the maximum value in the lower element of dst using writemask k (the element is copied from src when mask bit 0 is not set), and copy the upper element from a to the upper element of dst.

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