Function _mm_roundscale_sd

pub fn _mm_roundscale_sd<const IMM8: i32>(a: __m128d, b: __m128d) -> __m128d

Round 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 : use MXCSR.RC - see _MM_SET_ROUNDING_MODE

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