Function vset_lane_p64 

pub fn vset_lane_p64(a: u64, b: poly64x1_t, const LANE: i32) -> poly64x1_t

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

Insert vector element from another vector element Arm’s documentation