Note that imm (SVi) spans 7 bits (16 to 22), and that bit 22 and 23 is reserved and must be zero. Setting bit 22 or 23 causes an illegal exception.
+`ms` - bit 25 - allows for setting of MVL. `vs` - bit 24 - allows for
+setting of VL.
+
Note that in immediate setting mode VL and MVL start from **one** i.e. that an immediate value of zero will result in VL/MVL being set to 1. 0b111111 results in VL/MVL being set to 64. This is because setting VL/MVL to 1 results in "scalar identity" behaviour, where setting VL/MVL to 0 would result in all Vector operations becoming `nop`. If this is truly desired (nop behaviour) then setting VL and MVL to zero is to be done via the [[SV SPRs|sv/sprs]]
Note that setmvli is a pseudo-op, based on RA/RT=0, and setvli likewise