+ ty_args = mkTyVarTys $ tyConTyVars vect_tc
+ el_ty = mkTyConApp vect_tc ty_args
+
+ [pdata_dc] = tyConDataCons pdata_tc
+
+
+ to_sum EmptySum = do
+ pvoid <- builtin pvoidVar
+ return ([], Var pvoid)
+ to_sum (UnarySum r) = to_con r
+ to_sum (Sum { repr_psum_tc = psum_tc
+ , repr_sel_ty = sel_ty
+ , repr_con_tys = tys
+ , repr_cons = cons
+ })
+ = do
+ (vars, exprs) <- mapAndUnzipM to_con cons
+ sel <- newLocalVar (fsLit "sel") sel_ty
+ return (sel : concat vars, mk_result (Var sel) exprs)
+ where
+ [psum_con] = tyConDataCons psum_tc
+ mk_result sel exprs = wrapFamInstBody psum_tc tys
+ $ mkConApp psum_con
+ $ map Type tys ++ (sel : exprs)
+
+ to_con (ConRepr _ r) = to_prod r
+
+ to_prod EmptyProd = do
+ pvoid <- builtin pvoidVar
+ return ([], Var pvoid)
+ to_prod (UnaryProd r)
+ = do
+ pty <- mkPDataType (compOrigType r)
+ var <- newLocalVar (fsLit "x") pty
+ expr <- to_comp (Var var) r
+ return ([var], expr)
+
+ to_prod (Prod { repr_ptup_tc = ptup_tc
+ , repr_comp_tys = tys
+ , repr_comps = comps })
+ = do
+ ptys <- mapM (mkPDataType . compOrigType) comps
+ vars <- newLocalVars (fsLit "x") ptys
+ es <- zipWithM to_comp (map Var vars) comps
+ return (vars, mk_result es)
+ where
+ [ptup_con] = tyConDataCons ptup_tc
+ mk_result exprs = wrapFamInstBody ptup_tc tys
+ $ mkConApp ptup_con
+ $ map Type tys ++ exprs
+
+ to_comp expr (Keep _ _) = return expr
+
+ -- FIXME: this is bound to be wrong!
+ to_comp expr (Wrap ty)
+ = do
+ wrap_tc <- builtin wrapTyCon
+ (pwrap_tc, _) <- pdataReprTyCon (mkTyConApp wrap_tc [ty])
+ return $ wrapNewTypeBody pwrap_tc [ty] expr
+
+
+buildFromArrPRepr :: TyCon -> TyCon -> TyCon -> SumRepr -> VM CoreExpr
+buildFromArrPRepr vect_tc prepr_tc pdata_tc r
+ = do
+ arg_ty <- mkPDataType =<< mkPReprType el_ty
+ res_ty <- mkPDataType el_ty
+ arg <- newLocalVar (fsLit "xs") arg_ty
+
+ pdata_co <- mkBuiltinCo pdataTyCon
+ let Just repr_co = tyConFamilyCoercion_maybe prepr_tc
+ co = mkAppCoercion pdata_co
+ $ mkTyConApp repr_co var_tys
+
+ scrut = mkCoerce co (Var arg)
+
+ mk_result args = wrapFamInstBody pdata_tc var_tys
+ $ mkConApp pdata_con
+ $ map Type var_tys ++ args
+
+ (expr, _) <- fixV $ \ ~(_, args) ->
+ from_sum res_ty (mk_result args) scrut r
+
+ return $ Lam arg expr