let cvt_binop = function
PbinTimes -> CTTbinTimes
| PbinDiv -> CTTbinDiv
| PbinPlus | PbinMinus -> assert false
| PbinModulo -> CTTbinModulo
| PbinLshift -> CTTbinLshift
| PbinRshift -> CTTbinRshift
| PbinLogAnd -> CTTbinLogAnd
| PbinLogOr -> CTTbinLogOr
| PbinIntAnd -> CTTbinIntAnd
| PbinIntOr -> CTTbinIntOr
| PbinIntXor -> CTTbinIntXor
| PbinLessThan -> CTTbinLessThan
| PbinLessEqual -> CTTbinLessEqual
| PbinGtrThan -> CTTbinGtrThan
| PbinGtrEqual -> CTTbinGtrEqual
| PbinEqual -> CTTbinEqual
| PbinNotEqual -> CTTbinNotEqual