unsafe extern "C" fn vfixupimmsd(
    a: f64x2,
    b: f64x2,
    c: i64x2,
    imm8: i32,
    mask: u8,
    sae: i32
) -> f64x2
🔬This is a nightly-only experimental API. (stdsimd #48556)
Available on x86 or x86-64 only.