+type CoreAltWithFVs = AnnAlt Id VarSet
+
+-- We convert
+--
+-- case e :: t of v { ... }
+--
+-- to
+--
+-- V: let v = e in case v of _ { ... }
+-- L: let v = e in case v `cast` ... of _ { ... }
+--
+-- When lifting, we have to do it this way because v must have the type
+-- [:V(T):] but the scrutinee must be cast to the representation type.
+--
+
+-- FIXME: this is too lazy
+vectAlgCase scrut bndr ty [(DEFAULT, [], body)]
+ = do
+ vscrut <- vectExpr scrut
+ vty <- vectType ty
+ lty <- mkPArrayType vty
+ (vbndr, vbody) <- vectBndrIn bndr (vectExpr body)
+ return $ vCaseDEFAULT vscrut vbndr vty lty vbody
+
+vectAlgCase scrut bndr ty [(DataAlt dc, bndrs, body)]
+ = do
+ vty <- vectType ty
+ lty <- mkPArrayType vty
+ vexpr <- vectExpr scrut
+ (vbndr, (vbndrs, vbody)) <- vectBndrIn bndr
+ . vectBndrsIn bndrs
+ $ vectExpr body
+
+ (vscrut, arr_tc, arg_tys) <- mkVScrut (vVar vbndr)
+ vect_dc <- maybeV (lookupDataCon dc)
+ let [arr_dc] = tyConDataCons arr_tc
+ let shape_tys = take (dataConRepArity arr_dc - length bndrs)
+ (dataConRepArgTys arr_dc)
+ shape_bndrs <- mapM (newLocalVar FSLIT("s")) shape_tys
+ return . vLet (vNonRec vbndr vexpr)
+ $ vCaseProd vscrut vty lty vect_dc arr_dc shape_bndrs vbndrs vbody