$pseudo_op rv_zbkb::pack     zext.h.rv32 rd rs1 31..25=0x04 24..20=0 14..12=0x4 6..0=0x33
$pseudo_op rv64_zbp::grevi  rev8.rv32 rd rs1   31..20=0x698 14..12=5 6..0=0x13
$pseudo_op rv64_zbb::rori   rori.rv32 rd rs1   31..25=0x30 shamtw 14..12=5 6..2=0x04 1..0=3