Function `_mm_reduce_sd`

#[target_feature(enable = "avx512dq")]
pub fn _mm_reduce_sd(a: __m128d, b: __m128d, IMM8: i32) -> __m128d

Extract the reduced argument of the lower double-precision (64-bit) floating-point element in b by the number of bits specified by imm8, store the result in the lower element of dst using, and copy the upper element from a. to the upper element of dst. Rounding is done according to the imm8 parameter, which can be one of:

_MM_FROUND_TO_NEAREST_INT : round to nearest
_MM_FROUND_TO_NEG_INF : round down
_MM_FROUND_TO_POS_INF : round up
_MM_FROUND_TO_ZERO : truncate
_MM_FROUND_CUR_DIRECTION : use MXCSR.RC - see _MM_SET_ROUNDING_MODE

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