ref: d3392a19dbf9d1ee5c07cdd90f0ea725b5c0a10c 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*/