Function svrhadd_u64_z 

pub fn svrhadd_u64_z(
    pg: svbool_t,
    op1: svuint64_t,
    op2: svuint64_t,
) -> svuint64_t

🔬This is a nightly-only experimental API. (stdarch_aarch64_sve #145052)

Available on (AArch64 or ARM64EC) and target feature sve and target feature sve2 only.

Rounding halving add Arm’s documentation