pub unsafe fn _mm_maskz_getmant_round_sd<const NORM: i32, const SIGN: i32, const SAE: i32>(
    k: u8,
    a: __m128d,
    b: __m128d
) -> __m128d
🔬 This is a nightly-only experimental API. (stdsimd)
This is supported on x86-64 and target feature avx512f only.
Expand description

Normalize the mantissas of the lower double-precision (64-bit) floating-point element in b, store the result in the lower element of dst using zeromask k (the element is zeroed out when mask bit 0 is not set), and copy the upper element from a to the upper element of dst. This intrinsic essentially calculates ±(2^k)*|x.significand|, where k depends on the interval range defined by interv and the sign depends on sc and the source sign.
The mantissa is normalized to the interval specified by interv, which can take the following values:
_MM_MANT_NORM_1_2 // interval [1, 2)
_MM_MANT_NORM_p5_2 // interval [0.5, 2)
_MM_MANT_NORM_p5_1 // interval [0.5, 1)
_MM_MANT_NORM_p75_1p5 // interval [0.75, 1.5)
The sign is determined by sc which can take the following values:
_MM_MANT_SIGN_src // sign = sign(src)
_MM_MANT_SIGN_zero // sign = 0
_MM_MANT_SIGN_nan // dst = NaN if sign(src) = 1
Exceptions can be suppressed by passing _MM_FROUND_NO_EXC in the sae parameter.

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