+ These three operations can be very confusing so here is a mapping
+ between the instructions and the vselect node in one place:
+ bmz.v wd, ws, wt/i8 -> (vselect wt/i8, wd, ws)
+ bmnz.v wd, ws, wt/i8 -> (vselect wt/i8, ws, wd)
+ bsel.v wd, ws, wt/i8 -> (vselect wd, wt/i8, ws)