return
				}
				// For ARM64 CASP-like instructions, its 2nd destination operand is register pair(Rt, Rt+1) that can
				// not fit into prog.RegTo2, so save it to the prog.RestArgs.
				prog.AddRestDest(a[2])
			default:
				prog.From = a[0]
				prog.Reg = p.getRegister(prog, op, &a[1])
				prog.To = a[2]
			}
		case sys.I386:
			prog.From = a[0]
			prog.AddRestSource(a[1])