Function vdup_laneq_s64 

pub fn vdup_laneq_s64(a: int64x2_t, const N: i32) -> int64x1_t

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

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