prog.From = a[0]
				prog.AddRestSource(a[1])
				prog.To = a[2]
				break
			}
			// Otherwise the 2nd operand (a[1]) must be a register.
			prog.From = a[0]
			prog.Reg = p.getRegister(prog, op, &a[1])
			prog.To = a[2]
		case sys.AMD64:
			prog.From = a[0]
			prog.AddRestSource(a[1])
			prog.To = a[2]
		case sys.ARM64:
			switch {