-- And some particular Ids; see below for why they are wired in
wiredInIds, ghcPrimIds,
unsafeCoerceId, realWorldPrimId, voidArgId, nullAddrId, seqId,
- lazyId, lazyIdUnfolding, lazyIdKey,
+ lazyId, lazyIdUnfolding, lazyIdKey,
mkRuntimeErrorApp,
rEC_CON_ERROR_ID, iRREFUT_PAT_ERROR_ID, rUNTIME_ERROR_ID,
)
import TysWiredIn ( charTy, mkListTy )
import PrelRules ( primOpRules )
-import Type ( TyThing(..), mkForAllTy, tyVarsOfTypes, newTyConInstRhs )
-import Coercion ( mkSymCoercion, mkUnsafeCoercion,
- splitRecNewTypeCo_maybe )
+import Type ( TyThing(..), mkForAllTy, tyVarsOfTypes,
+ newTyConInstRhs, mkTopTvSubst, substTyVar, substTy )
+import TcGadt ( gadtRefine, refineType, emptyRefinement )
+import HsBinds ( ExprCoFn(..), isIdCoercion )
+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 )
+ tyConStupidTheta, isProductTyCon, isDataTyCon,
+ isRecursiveTyCon, tyConFamily_maybe, newTyConCo )
import Class ( Class, classTyCon, classSelIds )
-import Var ( Id, TyVar, Var )
+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, dataConInstTys,
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,
import DmdAnal ( dmdAnalTopRhs )
import CoreSyn
import Unique ( mkBuiltinUnique, mkPrimOpIdUnique )
+import Maybe ( fromJust )
import Maybes
import PrelNames
import Util ( dropList, isSingleton )
import Outputable
import FastString
-import ListSetOps ( assoc )
+import ListSetOps ( assoc, minusList )
\end{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
+ || not (null eq_spec)
+ || isInst
+ = DCIds (Just alg_wrap_id) wrk_id
| otherwise -- Algebraic, no wrapper
- = AlgDC Nothing wrk_id
+ = 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
-
- wrap_ty = mkForAllTys tvs (mkFunTys all_arg_tys result_ty)
+ (univ_tvs, ex_tvs, eq_spec,
+ theta, orig_arg_tys) = dataConFullSig data_con
+ tycon = dataConTyCon data_con
+ (isInst, instTys, familyTyCon) =
+ case dataConInstTys data_con of
+ Nothing -> (False, [] , familyTyCon)
+ Just instTys -> (True , instTys, familyTyCon)
+ where
+ familyTyCon = fromJust $ tyConFamily_maybe tycon
+ -- this is defined whenever `isInst'
+
+ ----------- 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
+ dict_tys = mkPredTys theta
+ result_ty_args = map (substTyVar subst) univ_tvs
+ familyArgs = map (substTy subst) instTys
+ result_ty = if isInst
+ then mkTyConApp familyTyCon familyArgs -- instance con
+ else mkTyConApp tycon result_ty_args -- ordinary con
+ 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
-- 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 &&
-- 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)
-- 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 = 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
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)
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
-- 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
+ ExprCoFn co -> Cast (Var the_arg_id) co
+ id_co -> ASSERT(isIdCoercion 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...
-- 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
- = mkUnpackCase the_id arg con_args boxing_con rhs
+unboxProduct :: Int -> CoreExpr -> Type -> (Int -> [Id] -> CoreExpr) -> CoreExpr
+unboxProduct i arg arg_ty body
+ = result
where
- (_, _, 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 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 unpk_args boxing_con body
- = Case cast_arg bndr (exprType body) [(DataAlt boxing_con, unpk_args, body)]
+ = Case cast_arg (setIdType bndr bndr_ty) (exprType body) [(DataAlt boxing_con, unpk_args, body)]
where
- cast_arg = go (idType bndr) arg
+ (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)
- | otherwise = arg
+ | otherwise = (arg, ty)
-- ...and the dual
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
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
+ | isNewTyCon tycon && not (isRecursiveTyCon tycon)
= wrap (mkProductBox arg_ids (newTyConInstRhs tycon tycon_args))
| otherwise = mkConApp pack_con (map Type tycon_args ++ map Var arg_ids)
where
stricts = dataConExStricts con ++ dataConStrictMarks con
- go [] stricts us = ([], [])
+ go [] _stricts _us = ([], [])
-- Type variable case
go (arg:args) stricts us
-- 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
--
wrapNewTypeBody tycon args result_expr
| Just co_con <- newTyConCo tycon
- = Cast result_expr (mkTyConApp co_con args)
+ = mkCoerce (mkSymCoercion (mkTyConApp co_con args)) result_expr
| otherwise
= result_expr
unwrapNewTypeBody :: TyCon -> [Type] -> CoreExpr -> CoreExpr
unwrapNewTypeBody tycon args result_expr
| Just co_con <- newTyConCo tycon
- = Cast result_expr (mkSymCoercion (mkTyConApp co_con args))
+ = mkCoerce (mkTyConApp co_con args) result_expr
| otherwise
= result_expr