ref: 7efba9bdc777541330e1b8fcd4a9e6e61a7a2b2d 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*/