Function _mm512_mask_reduce_mul_pd 

pub fn _mm512_mask_reduce_mul_pd(k: __mmask8, a: __m512d) -> f64

Available on x86-64 and target feature avx512f only.

Reduce the packed double-precision (64-bit) floating-point elements in a by multiplication using mask k. Returns the product of all active elements in a.

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