RLWMICC $7, R3, $16, $31, R6    // 50663c3f
	RLWNM $3, R4, $7, R6            // 54861f7e
	RLWNM $0, R4, $7, R6            // 5486077e
	RLWNM R0, R4, $7, R6            // 5c86077e
	RLWNM $3, R4, $29, $31, R6      // 54861f7e
	RLWNM $0, R4, $29, $31, R6      // 5486077e
	RLWNM R0, R4, $29, $31, R6      // 5c86077e
	RLWNM R3, R4, $7, R6            // 5c861f7e
	RLWNM R3, R4, $29, $31, R6      // 5c861f7e

				a.Index = arm64.REG_SXTW + Rnum
			} else {
				a.Reg = arm64.REG_SXTW + Rnum
			}
		case "SXTX":
			if a.Type == obj.TYPE_MEM {
				a.Index = arm64.REG_SXTX + Rnum
			} else {
				a.Reg = arm64.REG_SXTX + Rnum
			}
		case "LSL":
			a.Index = arm64.REG_LSL + Rnum
		default:
			return errors.New("unsupported general register extension type: " + ext)

		}
	} else if reg <= arm64.REG_V31 && reg >= arm64.REG_V0 {