Function _mm512_maskz_getexp_round_pd

#[target_feature(enable = "avx512f")]
pub fn _mm512_maskz_getexp_round_pd(k: __mmask8, a: __m512d, SAE: i32) -> __m512d

Convert the exponent of each packed double-precision (64-bit) floating-point element in a to a double-precision (64-bit) floating-point number representing the integer exponent, and store the results in dst using zeromask k (elements are zeroed out when the corresponding mask bit is not set). This intrinsic essentially calculates floor(log2(x)) for each element.
Exceptions can be suppressed by passing _MM_FROUND_NO_EXC in the sae parameter.

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