X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2FbasicTypes%2FMkId.lhs;h=9818eba2f99ec6ce93c42c291f5cc0adeb1c0f22;hp=1c25d8125ee982542bb27d15553eb31691bef1c3;hb=b00b5bc04ff36a551552470060064f0b7d84ca30;hpb=6fcf90065dc4e75b7dc6bbf238a9891a71ae5a86 diff --git a/compiler/basicTypes/MkId.lhs b/compiler/basicTypes/MkId.lhs index 1c25d81..9818eba 100644 --- a/compiler/basicTypes/MkId.lhs +++ b/compiler/basicTypes/MkId.lhs @@ -46,38 +46,45 @@ import TysPrim ( openAlphaTyVars, alphaTyVar, alphaTy, ) import TysWiredIn ( charTy, mkListTy ) import PrelRules ( primOpRules ) -import Type ( TyThing(..), mkForAllTy, tyVarsOfTypes, newTyConInstRhs, coreEqType ) -import Coercion ( mkSymCoercion, mkUnsafeCoercion, - splitNewTypeRepCo_maybe ) +import Type ( TyThing(..), mkForAllTy, tyVarsOfTypes, + newTyConInstRhs, mkTopTvSubst, substTyVar, + substTys, zipTopTvSubst ) +import TcGadt ( gadtRefine, refineType, emptyRefinement ) +import HsBinds ( HsWrapper(..), isIdHsWrapper ) +import Coercion ( mkSymCoercion, mkUnsafeCoercion, isEqPred ) import TcType ( Type, ThetaType, mkDictTy, mkPredTys, mkPredTy, - mkTyConApp, mkTyVarTys, mkClassPred, - mkFunTys, mkFunTy, mkSigmaTy, tcSplitSigmaTy, + mkTyConApp, mkTyVarTys, mkClassPred, isPredTy, + mkFunTys, mkFunTy, mkSigmaTy, tcSplitSigmaTy, tcEqType, isUnLiftedType, mkForAllTys, mkTyVarTy, tyVarsOfType, tcSplitFunTys, tcSplitForAllTys, dataConsStupidTheta ) -import CoreUtils ( exprType ) +import CoreUtils ( exprType, dataConOrigInstPat, mkCoerce ) import CoreUnfold ( mkTopUnfolding, mkCompulsoryUnfolding ) import Literal ( nullAddrLit, mkStringLit ) -import TyCon ( TyCon, isNewTyCon, tyConDataCons, FieldLabel, - tyConStupidTheta, isProductTyCon, isDataTyCon, isRecursiveTyCon, - newTyConCo, tyConArity ) +import TyCon ( TyCon, isNewTyCon, tyConTyVars, tyConDataCons, + FieldLabel, + tyConStupidTheta, isProductTyCon, isDataTyCon, + isRecursiveTyCon, isFamInstTyCon, + tyConFamInst_maybe, tyConFamilyCoercion_maybe, + newTyConCo_maybe ) import Class ( Class, classTyCon, classSelIds ) import Var ( Id, TyVar, Var, setIdType ) import VarSet ( isEmptyVarSet, subVarSet, varSetElems ) -import Name ( mkFCallName, mkWiredInName, Name, BuiltInSyntax(..) ) +import Name ( mkFCallName, mkWiredInName, Name, BuiltInSyntax(..)) import OccName ( mkOccNameFS, varName ) import PrimOp ( PrimOp, primOpSig, primOpOcc, primOpTag ) import ForeignCall ( ForeignCall ) -import DataCon ( DataCon, DataConIds(..), dataConTyCon, dataConUnivTyVars, +import DataCon ( DataCon, DataConIds(..), dataConTyCon, + dataConUnivTyVars, dataConFieldLabels, dataConRepArity, dataConResTys, - dataConRepArgTys, dataConRepType, - dataConSig, dataConStrictMarks, dataConExStricts, + dataConRepArgTys, dataConRepType, dataConFullSig, + dataConStrictMarks, dataConExStricts, splitProductType, isVanillaDataCon, dataConFieldType, - dataConInstOrigArgTys, deepSplitProductType + deepSplitProductType, ) import Id ( idType, mkGlobalId, mkVanillaGlobal, mkSysLocal, mkTemplateLocals, mkTemplateLocalsNum, mkExportedLocalId, - mkTemplateLocal, idName, mkWildId + mkTemplateLocal, idName ) import IdInfo ( IdInfo, noCafIdInfo, setUnfoldingInfo, setArityInfo, setSpecInfo, setCafInfo, @@ -95,7 +102,7 @@ import PrelNames import Util ( dropList, isSingleton ) import Outputable import FastString -import ListSetOps ( assoc ) +import ListSetOps ( assoc, minusList ) \end{code} %************************************************************************ @@ -185,32 +192,76 @@ Notice that Making an explicit case expression allows the simplifier to eliminate it in the (common) case where the constructor arg is already evaluated. +[Wrappers for data instance tycons] +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +In the case of data instances, the wrapper also applies the coercion turning +the representation type into the family instance type to cast the result of +the wrapper. For example, consider the declarations + + data family Map k :: * -> * + data instance Map (a, b) v = MapPair (Map a (Pair b v)) + +The tycon to which the datacon MapPair belongs gets a unique internal name of +the form :R123Map, and we call it the representation tycon. In contrast, Map +is the family tycon (accessible via tyConFamInst_maybe). The wrapper and work +of MapPair get the types + + $WMapPair :: forall a b v. Map a (Map a b v) -> Map (a, b) v + $wMapPair :: forall a b v. Map a (Map a b v) -> :R123Map a b v + +which implies that the wrapper code will have to apply the coercion moving +between representation and family type. It is accessible via +tyConFamilyCoercion_maybe and has kind + + Co123Map a b v :: {Map (a, b) v :=: :R123Map a b v} + +This coercion is conditionally applied by wrapFamInstBody. \begin{code} mkDataConIds :: Name -> Name -> DataCon -> DataConIds mkDataConIds wrap_name wkr_name data_con | isNewTyCon tycon - = NewDC nt_wrap_id + = DCIds Nothing nt_work_id -- Newtype, only has a worker - | any isMarkedStrict all_strict_marks -- Algebraic, needs wrapper - = AlgDC (Just alg_wrap_id) wrk_id + | any isMarkedStrict all_strict_marks -- Algebraic, needs wrapper + || not (null eq_spec) -- NB: LoadIface.ifaceDeclSubBndrs + || isFamInstTyCon tycon -- depends on this test + = DCIds (Just alg_wrap_id) wrk_id - | otherwise -- Algebraic, no wrapper - = AlgDC Nothing wrk_id + | otherwise -- Algebraic, no wrapper + = DCIds Nothing wrk_id where - (tvs, theta, orig_arg_tys) = dataConSig data_con - tycon = dataConTyCon data_con - - dict_tys = mkPredTys theta - all_arg_tys = dict_tys ++ orig_arg_tys - tycon_args = dataConUnivTyVars data_con - result_ty_args = (mkTyVarTys tycon_args) - result_ty = mkTyConApp tycon result_ty_args + (univ_tvs, ex_tvs, eq_spec, + theta, orig_arg_tys) = dataConFullSig data_con + tycon = dataConTyCon data_con - wrap_ty = mkForAllTys tvs (mkFunTys all_arg_tys result_ty) + ----------- Wrapper -------------- -- We used to include the stupid theta in the wrapper's args -- but now we don't. Instead the type checker just injects these -- extra constraints where necessary. + wrap_tvs = (univ_tvs `minusList` map fst eq_spec) ++ ex_tvs + subst = mkTopTvSubst eq_spec + famSubst = ASSERT( length (tyConTyVars tycon ) == + length (mkTyVarTys univ_tvs) ) + zipTopTvSubst (tyConTyVars tycon) (mkTyVarTys univ_tvs) + -- substitution mapping the type constructor's type + -- arguments to the universals of the data constructor + -- (crucial when type checking interfaces) + dict_tys = mkPredTys theta + result_ty_args = map (substTyVar subst) univ_tvs + result_ty = case tyConFamInst_maybe tycon of + -- ordinary constructor + Nothing -> mkTyConApp tycon result_ty_args + -- family instance constructor + Just (familyTyCon, + instTys) -> + mkTyConApp familyTyCon ( substTys subst + . substTys famSubst + $ instTys) + wrap_ty = mkForAllTys wrap_tvs $ mkFunTys dict_tys $ + mkFunTys orig_arg_tys $ result_ty + -- NB: watch out here if you allow user-written equality + -- constraints in data constructor signatures ----------- Worker (algebraic data types only) -------------- -- The *worker* for the data constructor is the function that @@ -250,9 +301,9 @@ mkDataConIds wrap_name wkr_name data_con -- RetCPR is only true for products that are real data types; -- that is, not unboxed tuples or [non-recursive] newtypes - ----------- Wrappers for newtypes -------------- - nt_wrap_id = mkGlobalId (DataConWrapId data_con) wrap_name wrap_ty nt_wrap_info - nt_wrap_info = noCafIdInfo -- The NoCaf-ness is set by noCafIdInfo + ----------- Workers for newtypes -------------- + nt_work_id = mkGlobalId (DataConWrapId data_con) wkr_name wrap_ty nt_work_info + nt_work_info = noCafIdInfo -- The NoCaf-ness is set by noCafIdInfo `setArityInfo` 1 -- Arity 1 `setUnfoldingInfo` newtype_unf newtype_unf = ASSERT( isVanillaDataCon data_con && @@ -260,7 +311,7 @@ mkDataConIds wrap_name wkr_name data_con -- No existentials on a newtype, but it can have a context -- e.g. newtype Eq a => T a = MkT (...) mkCompulsoryUnfolding $ - mkLams tvs $ Lam id_arg1 $ + mkLams wrap_tvs $ Lam id_arg1 $ wrapNewTypeBody tycon result_ty_args (Var id_arg1) @@ -290,14 +341,17 @@ mkDataConIds wrap_name wkr_name data_con -- we want to see that w is strict in its two arguments alg_unf = mkTopUnfolding $ Note InlineMe $ - mkLams tvs $ + mkLams wrap_tvs $ mkLams dict_args $ mkLams id_args $ foldr mk_case con_app (zip (dict_args ++ id_args) all_strict_marks) i3 [] - con_app i rep_ids = mkApps (Var wrk_id) - (map varToCoreExpr (tvs ++ reverse rep_ids)) + con_app _ rep_ids = wrapFamInstBody tycon result_ty_args $ + Var wrk_id `mkTyApps` result_ty_args + `mkVarApps` ex_tvs + `mkTyApps` map snd eq_spec + `mkVarApps` reverse rep_ids (dict_args,i2) = mkLocals 1 dict_tys (id_args,i3) = mkLocals i2 orig_arg_tys @@ -318,7 +372,7 @@ mkDataConIds wrap_name wkr_name data_con Case (Var arg) arg result_ty [(DEFAULT,[], body i (arg:rep_args))] MarkedUnboxed - -> unboxProduct i (Var arg) (idType arg) the_body result_ty + -> unboxProduct i (Var arg) (idType arg) the_body where the_body i con_args = body i (reverse con_args ++ rep_args) @@ -336,6 +390,18 @@ mAX_CPR_SIZE = 10 mkLocals i tys = (zipWith mkTemplateLocal [i..i+n-1] tys, i+n) where n = length tys + +-- If the type constructor is a representation type of a data instance, wrap +-- the expression into a cast adjusting the expression type, which is an +-- instance of the representation type, to the corresponding instance of the +-- family instance type. +-- +wrapFamInstBody :: TyCon -> [Type] -> CoreExpr -> CoreExpr +wrapFamInstBody tycon args result_expr + | Just co_con <- tyConFamilyCoercion_maybe tycon + = mkCoerce (mkSymCoercion (mkTyConApp co_con args)) result_expr + | otherwise + = result_expr \end{code} @@ -461,7 +527,9 @@ mkRecordSelId tycon field_label stupid_dict_tys = mkPredTys (dataConsStupidTheta data_cons_w_field) n_stupid_dicts = length stupid_dict_tys - (field_tyvars,field_theta,field_tau) = tcSplitSigmaTy field_ty + (field_tyvars,pre_field_theta,field_tau) = tcSplitSigmaTy field_ty + + field_theta = filter (not . isEqPred) pre_field_theta field_dict_tys = mkPredTys field_theta n_field_dict_tys = length field_dict_tys -- If the field has a universally quantified type we have to @@ -538,28 +606,37 @@ mkRecordSelId tycon field_label -- foo = /\a. \t:T. case t of { MkT f -> f a } mk_alt data_con - = -- In the non-vanilla case, the pattern must bind type variables and - -- the context stuff; hence the arg_prefix binding below - mkReboxingAlt uniqs data_con (arg_prefix ++ arg_ids) (Var the_arg_id) + = ASSERT2( res_ty `tcEqType` field_ty, ppr data_con $$ ppr res_ty $$ ppr field_ty ) + mkReboxingAlt rebox_uniqs data_con (ex_tvs ++ co_tvs ++ arg_vs) rhs where - (arg_prefix, arg_ids) - | isVanillaDataCon data_con -- Instantiate from commmon base - = ([], mkTemplateLocalsNum arg_base (dataConInstOrigArgTys data_con res_tys)) - | otherwise -- The case pattern binds type variables, which are used - -- in the types of the arguments of the pattern - = (dc_tvs ++ mkTemplateLocalsNum arg_base (mkPredTys dc_theta), - mkTemplateLocalsNum arg_base' dc_arg_tys) - - (dc_tvs, dc_theta, dc_arg_tys) = dataConSig data_con - arg_base' = arg_base + length dc_theta - - unpack_base = arg_base' + length dc_arg_tys - uniqs = map mkBuiltinUnique [unpack_base..] - - the_arg_id = assoc "mkRecordSelId:mk_alt" (field_lbls `zip` arg_ids) field_label + -- get pattern binders with types appropriately instantiated + arg_uniqs = map mkBuiltinUnique [arg_base..] + (ex_tvs, co_tvs, arg_vs) = dataConOrigInstPat arg_uniqs data_con res_tys + + rebox_base = arg_base + length ex_tvs + length co_tvs + length arg_vs + rebox_uniqs = map mkBuiltinUnique [rebox_base..] + + -- data T :: *->* where T1 { fld :: Maybe b } -> T [b] + -- Hence T1 :: forall a b. (a=[b]) => b -> T a + -- fld :: forall b. T [b] -> Maybe b + -- fld = /\b.\(t:T[b]). case t of + -- T1 b' (c : [b]=[b']) (x:Maybe b') + -- -> x `cast` Maybe (sym (right c)) + + Succeeded refinement = gadtRefine emptyRefinement ex_tvs co_tvs + (co_fn, res_ty) = refineType refinement (idType the_arg_id) + -- Generate the refinement for b'=b, + -- and apply to (Maybe b'), to get (Maybe b) + + rhs = case co_fn of + WpCo co -> Cast (Var the_arg_id) co + id_co -> ASSERT(isIdHsWrapper id_co) Var the_arg_id + + field_vs = filter (not . isPredTy . idType) arg_vs + the_arg_id = assoc "mkRecordSelId:mk_alt" (field_lbls `zip` field_vs) field_label field_lbls = dataConFieldLabels data_con - error_expr = mkRuntimeErrorApp rEC_SEL_ERROR_ID field_tau full_msg + error_expr = mkRuntimeErrorApp rEC_SEL_ERROR_ID field_ty full_msg full_msg = showSDoc (sep [text "No match in record selector", ppr sel_id]) -- unbox a product type... @@ -573,32 +650,32 @@ mkRecordSelId tycon field_label -- If we have e = MkT (MkS (PairInt 0 1)) and some body expecting a list of -- ids, we get (modulo int passing) -- --- case (e `cast` (sym CoT)) `cast` (sym CoS) of +-- case (e `cast` CoT) `cast` CoS of -- PairInt a b -> body [a,b] -- -- The Ints passed around are just for creating fresh locals -unboxProduct :: Int -> CoreExpr -> Type -> (Int -> [Id] -> CoreExpr) -> Type -> CoreExpr -unboxProduct i arg arg_ty body res_ty +unboxProduct :: Int -> CoreExpr -> Type -> (Int -> [Id] -> CoreExpr) -> CoreExpr +unboxProduct i arg arg_ty body = result where - result = mkUnpackCase the_id arg arg_ty con_args boxing_con rhs - (tycon, tycon_args, boxing_con, tys) = deepSplitProductType "unboxProduct" arg_ty + result = mkUnpackCase the_id arg con_args boxing_con rhs + (_tycon, _tycon_args, boxing_con, tys) = deepSplitProductType "unboxProduct" arg_ty ([the_id], i') = mkLocals i [arg_ty] (con_args, i'') = mkLocals i' tys rhs = body i'' con_args -mkUnpackCase :: Id -> CoreExpr -> Type -> [Id] -> DataCon -> CoreExpr -> CoreExpr +mkUnpackCase :: Id -> CoreExpr -> [Id] -> DataCon -> CoreExpr -> CoreExpr -- (mkUnpackCase x e args Con body) -- returns -- case (e `cast` ...) of bndr { Con args -> body } -- -- the type of the bndr passed in is irrelevent -mkUnpackCase bndr arg arg_ty unpk_args boxing_con body +mkUnpackCase bndr arg unpk_args boxing_con body = Case cast_arg (setIdType bndr bndr_ty) (exprType body) [(DataAlt boxing_con, unpk_args, body)] where (cast_arg, bndr_ty) = go (idType bndr) arg go ty arg - | res@(tycon, tycon_args, _, _) <- splitProductType "mkUnpackCase" ty + | (tycon, tycon_args, _, _) <- splitProductType "mkUnpackCase" ty , isNewTyCon tycon && not (isRecursiveTyCon tycon) = go (newTyConInstRhs tycon tycon_args) (unwrapNewTypeBody tycon tycon_args arg) @@ -612,7 +689,7 @@ reboxProduct :: [Unique] -- uniques to create new local binders [Id]) -- Ids being boxed into product reboxProduct us ty = let - (tycon, tycon_args, pack_con, con_arg_tys) = deepSplitProductType "reboxProduct" ty + (_tycon, _tycon_args, _pack_con, con_arg_tys) = deepSplitProductType "reboxProduct" ty us' = dropList con_arg_tys us @@ -627,7 +704,7 @@ mkProductBox :: [Id] -> Type -> CoreExpr mkProductBox arg_ids ty = result_expr where - (tycon, tycon_args, pack_con, con_arg_tys) = splitProductType "mkProductBox" ty + (tycon, tycon_args, pack_con, _con_arg_tys) = splitProductType "mkProductBox" ty result_expr | isNewTyCon tycon && not (isRecursiveTyCon tycon) @@ -670,7 +747,7 @@ mkReboxingAlt us con args rhs where stricts = dataConExStricts con ++ dataConStrictMarks con - go [] stricts us = ([], []) + go [] _stricts _us = ([], []) -- Type variable case go (arg:args) stricts us @@ -763,26 +840,39 @@ wrapNewTypeBody :: TyCon -> [Type] -> CoreExpr -> CoreExpr -- The wrapper for the data constructor for a newtype looks like this: -- newtype T a = MkT (a,Int) -- MkT :: forall a. (a,Int) -> T a --- MkT = /\a. \(x:(a,Int)). x `cast` CoT a +-- MkT = /\a. \(x:(a,Int)). x `cast` sym (CoT a) -- where CoT is the coercion TyCon assoicated with the newtype -- -- The call (wrapNewTypeBody T [a] e) returns the -- body of the wrapper, namely --- e `cast` CoT [a] +-- e `cast` (CoT [a]) -- -- If a coercion constructor is prodivided in the newtype, then we use -- it, otherwise the wrap/unwrap are both no-ops -- +-- If the we are dealing with a newtype instance, we have a second coercion +-- identifying the family instance with the constructor of the newtype +-- instance. This coercion is applied in any case (ie, composed with the +-- coercion constructor of the newtype or applied by itself). +-- wrapNewTypeBody tycon args result_expr - | Just co_con <- newTyConCo tycon - = Cast result_expr (mkTyConApp co_con args) - | otherwise - = result_expr + = wrapFamInstBody tycon args inner + where + inner + | Just co_con <- newTyConCo_maybe tycon + = mkCoerce (mkSymCoercion (mkTyConApp co_con args)) result_expr + | otherwise + = result_expr +-- When unwrapping, we do *not* apply any family coercion, because this will +-- be done via a CoPat by the type checker. We have to do it this way as +-- computing the right type arguments for the coercion requires more than just +-- a spliting operation (cf, TcPat.tcConPat). +-- unwrapNewTypeBody :: TyCon -> [Type] -> CoreExpr -> CoreExpr unwrapNewTypeBody tycon args result_expr - | Just co_con <- newTyConCo tycon - = Cast result_expr (mkSymCoercion (mkTyConApp co_con args)) + | Just co_con <- newTyConCo_maybe tycon + = mkCoerce (mkTyConApp co_con args) result_expr | otherwise = result_expr @@ -805,7 +895,7 @@ mkPrimOpId prim_op ty = mkForAllTys tyvars (mkFunTys arg_tys res_ty) name = mkWiredInName gHC_PRIM (primOpOcc prim_op) (mkPrimOpIdUnique (primOpTag prim_op)) - Nothing (AnId id) UserSyntax + (AnId id) UserSyntax id = mkGlobalId (PrimOpId prim_op) name ty info info = noCafIdInfo @@ -944,7 +1034,7 @@ another gun with which to shoot yourself in the foot. \begin{code} mkWiredInIdName mod fs uniq id - = mkWiredInName mod (mkOccNameFS varName fs) uniq Nothing (AnId id) UserSyntax + = mkWiredInName mod (mkOccNameFS varName fs) uniq (AnId id) UserSyntax unsafeCoerceName = mkWiredInIdName gHC_PRIM FSLIT("unsafeCoerce#") unsafeCoerceIdKey unsafeCoerceId nullAddrName = mkWiredInIdName gHC_PRIM FSLIT("nullAddr#") nullAddrIdKey nullAddrId