Function _mm_roundscale_sd
#[target_feature(enable = "avx512f")]
pub fn _mm_roundscale_sd(a: __m128d, b: __m128d, IMM8: i32) -> __m128dRound the lower double-precision (64-bit) floating-point element in b to the number of fraction bits specified by imm8, store the result in the lower element of dst, and copy the upper element from a to the upper element of dst.
Rounding is done according to the imm8[2:0] 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: useMXCSR.RC- see_MM_SET_ROUNDING_MODE