Function vcombine_s32 

pub fn vcombine_s32(a: int32x2_t, b: int32x2_t) -> int32x4_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.

Join two smaller vectors into a single larger vector Arm’s documentation