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## _mm_getmant_round_sh

# Function _mm_getmant_round_sh

1.94.0 · Source

    pub fn _mm_getmant_round_sh(
        a: __m128h,
        b: __m128h,
        const NORM: _MM_MANTISSA_NORM_ENUM,
        const SIGN: _MM_MANTISSA_SIGN_ENUM,
        const SAE: i32,
    ) -> __m128h

Available on x86-64 and target feature `avx512fp16` only.
Expand description

Normalize the mantissas of the lower half-precision (16-bit) floating-point element in b, store the result in the lower element of dst, and copy the upper 7 packed elements from a to the upper elements of dst. This intrinsic essentially calculates `±(2^k)*|x.significand|`, where k depends on the interval range defined by norm and the sign depends on sign and the source sign. Exceptions can be suppressed by passing _MM_FROUND_NO_EXC in the sae parameter

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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