+buildFromPRepr :: Shape -> TyCon -> TyCon -> TyCon -> VM CoreExpr
+buildFromPRepr _ vect_tc prepr_tc _
+ = do
+ arg_ty <- mkPReprType res_ty
+ arg <- newLocalVar FSLIT("x") arg_ty
+ alts <- mapM mk_alt data_cons
+ body <- mkFromPRepr (unwrapFamInstScrut prepr_tc var_tys (Var arg))
+ res_ty alts
+ return $ Lam arg body
+ where
+ var_tys = mkTyVarTys $ tyConTyVars vect_tc
+ res_ty = mkTyConApp vect_tc var_tys
+ data_cons = tyConDataCons vect_tc
+
+ mk_alt dc = do
+ bndrs <- mapM (newLocalVar FSLIT("x")) $ dataConRepArgTys dc
+ return (bndrs, mkConApp dc (map Type var_tys ++ map Var bndrs))
+