pub unsafe fn _mm_cvt_roundu64_sd(
    a: __m128d,
    b: u64,
    const ROUNDING: i32
) -> __m128d
🔬This is a nightly-only experimental API. (stdarch_x86_avx512 #111137)
Available on x86-64 and target feature avx512f only.
Expand description

Convert the unsigned 64-bit integer b to a double-precision (64-bit) floating-point element, 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 rounding[3:0] 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

Intel’s documentation