Function vdup_lane_s64 

pub fn vdup_lane_s64(a: int64x1_t, const N: i32) -> int64x1_t

Available on target feature neon and (AArch64 or ARM or ARM64EC) and (AArch64 or ARM64EC) and (AArch64 or ARM64EC or target feature v7) only.

Set all vector lanes to the same value Arm’s documentation