Function _mm_round_sd 

pub fn _mm_round_sd(a: __m128d, b: __m128d, const ROUNDING: i32) -> __m128d

Available on x86 and target feature sse4.1 only.

Round the lower double-precision (64-bit) floating-point element in b using the ROUNDING parameter, store the result as a double-precision floating-point element in the lower element of the intrinsic result, and copies the upper element from a to the upper element of the intrinsic result. Rounding is done according to the rounding parameter, which can be one of:

• _MM_FROUND_TO_NEAREST_INT | _MM_FROUND_NO_EXC : round to nearest and suppress exceptions
• _MM_FROUND_TO_NEG_INF | _MM_FROUND_NO_EXC : round down and suppress exceptions
• _MM_FROUND_TO_POS_INF | _MM_FROUND_NO_EXC : round up and suppress exceptions
• _MM_FROUND_TO_ZERO | _MM_FROUND_NO_EXC : truncate and suppress exceptions
• _MM_FROUND_CUR_DIRECTION : use MXCSR.RC - see _MM_SET_ROUNDING_MODE

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