ref: e03915a9f7d8c040c3b7f4e8de4f69f62aeefc99 dir: /sys/src/cmd/9l/needed/
> case ASLQ: /* 6 and 57 */ > case ASRAQ: /* sraw Rb,Rs,Ra; srawi sh,Rs,Ra */ /* 6 and 56 */ > case ARLQMI: /* unique, also clear, clearleft clearright*/