mkDictFunId, mkDefaultMethodId,
mkDictSelId,
- mkDataConId, mkDataConWrapId,
+ mkDataConWorkId, mkDataConWrapId,
mkRecordSelId,
mkPrimOpId, mkFCallId,
import BasicTypes ( Arity, StrictnessMark(..), isMarkedUnboxed, isMarkedStrict )
-import TysPrim ( openAlphaTyVars, alphaTyVar, alphaTy, betaTyVar, betaTy,
- intPrimTy, realWorldStatePrimTy, addrPrimTy
+import TysPrim ( openAlphaTyVars, alphaTyVar, alphaTy,
+ realWorldStatePrimTy, addrPrimTy
)
import TysWiredIn ( charTy, mkListTy )
import PrelRules ( primOpRules )
import Var ( Id, TyVar, Var )
import VarSet ( isEmptyVarSet )
import Name ( mkFCallName, Name )
-import PrimOp ( PrimOp(DataToTagOp), primOpSig, mkPrimOpIdName )
+import PrimOp ( PrimOp, primOpSig, mkPrimOpIdName )
import ForeignCall ( ForeignCall )
import DataCon ( DataCon,
dataConFieldLabels, dataConRepArity, dataConTyCon,
dataConArgTys, dataConRepType,
dataConOrigArgTys,
- dataConName, dataConTheta,
+ dataConTheta,
dataConSig, dataConStrictMarks, dataConWorkId,
splitProductType
)
-import Id ( idType, mkGlobalId, mkVanillaGlobal, mkSysLocal,
- mkTemplateLocals, mkTemplateLocalsNum,
+import Id ( idType, mkGlobalId, mkVanillaGlobal, mkSysLocal, mkLocalId,
+ mkTemplateLocals, mkTemplateLocalsNum, setIdLocalExported,
mkTemplateLocal, idNewStrictness, idName
)
-import IdInfo ( IdInfo, noCafIdInfo, hasCafIdInfo,
- setUnfoldingInfo,
+import IdInfo ( IdInfo, noCafIdInfo, setUnfoldingInfo,
setArityInfo, setSpecInfo, setCafInfo,
- setAllStrictnessInfo,
+ setAllStrictnessInfo, vanillaIdInfo,
GlobalIdDetails(..), CafInfo(..)
)
import NewDemand ( mkStrictSig, strictSigResInfo, DmdResult(..),
realWorldPrimId,
unsafeCoerceId,
nullAddrId,
- getTagId,
seqId
]
\end{code}
%************************************************************************
\begin{code}
-mkDataConId :: Name -> DataCon -> Id
+mkDataConWorkId :: Name -> DataCon -> Id
-- Makes the *worker* for the data constructor; that is, the function
-- that takes the reprsentation arguments and builds the constructor.
-mkDataConId work_name data_con
- = mkGlobalId (DataConId data_con) work_name (dataConRepType data_con) info
+mkDataConWorkId wkr_name data_con
+ = mkGlobalId (DataConWorkId data_con) wkr_name
+ (dataConRepType data_con) info
where
info = noCafIdInfo
`setArityInfo` arity
`setAllStrictnessInfo` Just strict_sig
arity = dataConRepArity data_con
-
strict_sig = mkStrictSig (mkTopDmdType (replicate arity topDmd) cpr_info)
-- Notice that we do *not* say the worker is strict
-- even if the data constructor is declared strict
it in the (common) case where the constructor arg is already evaluated.
\begin{code}
-mkDataConWrapId data_con
- = mkGlobalId (DataConWrapId data_con) (dataConName data_con) wrap_ty info
+mkDataConWrapId :: Name -> DataCon -> Maybe Id
+-- Only make a wrapper Id if necessary
+
+mkDataConWrapId wrap_name data_con
+ | is_newtype || any isMarkedStrict strict_marks
+ = -- We need a wrapper function
+ Just (mkGlobalId (DataConWrapId data_con) wrap_name wrap_ty info)
+
+ | otherwise
+ = Nothing -- The common case, where there is no point in
+ -- having a wrapper function. Not only is this efficient,
+ -- but it also ensures that the wrapper is replaced
+ -- by the worker (becuase it *is* the wroker)
+ -- even when there are no args. E.g. in
+ -- f (:) x
+ -- the (:) *is* the worker.
+ -- This is really important in rule matching,
+ -- (We could match on the wrappers,
+ -- but that makes it less likely that rules will match
+ -- when we bring bits of unfoldings together.)
where
- work_id = dataConWorkId data_con
+ (tyvars, _, ex_tyvars, ex_theta, orig_arg_tys, tycon) = dataConSig data_con
+ is_newtype = isNewTyCon tycon
+ all_tyvars = tyvars ++ ex_tyvars
+ work_id = dataConWorkId data_con
- info = noCafIdInfo
- `setUnfoldingInfo` wrap_unf
- -- The NoCaf-ness is set by noCafIdInfo
- `setArityInfo` arity
+ common_info = noCafIdInfo -- The NoCaf-ness is set by noCafIdInfo
+ `setArityInfo` arity
-- It's important to specify the arity, so that partial
-- applications are treated as values
- `setAllStrictnessInfo` Just wrap_sig
+
+ info | is_newtype = common_info `setUnfoldingInfo` newtype_unf
+ | otherwise = common_info `setUnfoldingInfo` data_unf
+ `setAllStrictnessInfo` Just wrap_sig
wrap_sig = mkStrictSig (mkTopDmdType arg_dmds res_info)
res_info = strictSigResInfo (idNewStrictness work_id)
-- ...(let w = C x in ...(w p q)...)...
-- we want to see that w is strict in its two arguments
- wrap_unf | isNewTyCon tycon
- = ASSERT( null ex_tyvars && null ex_dict_args && isSingleton orig_arg_tys )
- -- No existentials on a newtype, but it can have a context
- -- e.g. newtype Eq a => T a = MkT (...)
- mkTopUnfolding $ Note InlineMe $
- mkLams tyvars $ Lam id_arg1 $
- mkNewTypeBody tycon result_ty (Var id_arg1)
-
- | not (any isMarkedStrict strict_marks)
- = mkCompulsoryUnfolding (Var work_id)
- -- The common case. Not only is this efficient,
- -- but it also ensures that the wrapper is replaced
- -- by the worker even when there are no args.
- -- f (:) x
- -- becomes
- -- f $w: x
- -- This is really important in rule matching,
- -- (We could match on the wrappers,
- -- but that makes it less likely that rules will match
- -- when we bring bits of unfoldings together.)
- --
- -- NB: because of this special case, (map (:) ys) turns into
- -- (map $w: ys). The top-level defn for (:) is never used.
- -- This is somewhat of a bore, but I'm currently leaving it
- -- as is, so that there still is a top level curried (:) for
- -- the interpreter to call.
-
- | otherwise
- = mkTopUnfolding $ Note InlineMe $
+ newtype_unf = ASSERT( null ex_tyvars && null ex_dict_args &&
+ isSingleton orig_arg_tys )
+ -- No existentials on a newtype, but it can have a context
+ -- e.g. newtype Eq a => T a = MkT (...)
+ mkTopUnfolding $ Note InlineMe $
+ mkLams tyvars $ Lam id_arg1 $
+ mkNewTypeBody tycon result_ty (Var id_arg1)
+
+ data_unf = mkTopUnfolding $ Note InlineMe $
mkLams all_tyvars $
mkLams ex_dict_args $ mkLams id_args $
foldr mk_case con_app
con_app i rep_ids = mkApps (Var work_id)
(map varToCoreExpr (all_tyvars ++ reverse rep_ids))
- (tyvars, _, ex_tyvars, ex_theta, orig_arg_tys, tycon) = dataConSig data_con
- all_tyvars = tyvars ++ ex_tyvars
-
ex_dict_tys = mkPredTys ex_theta
all_arg_tys = ex_dict_tys ++ orig_arg_tys
result_ty = mkTyConApp tycon (mkTyVarTys tyvars)
(not f :: R -> forall a. a->a, which gives the type inference mechanism
problems at call sites)
-Similarly for newtypes
+Similarly for (recursive) newtypes
newtype N = MkN { unN :: forall a. a->a }
- unN :: forall a. N -> a -> a
- unN = /\a -> \n:N -> coerce (a->a) n
+ unN :: forall b. N -> b -> b
+ unN = /\b -> \n:N -> (coerce (forall a. a->a) n)
\begin{code}
mkRecordSelId tycon field_label
mkLams dict_ids $ mkLams field_dict_ids $
Lam data_id $ sel_body
- sel_body | isNewTyCon tycon = mkNewTypeBody tycon field_tau (mk_result data_id)
+ sel_body | isNewTyCon tycon = mk_result (mkNewTypeBody tycon field_ty (Var data_id))
| otherwise = Case (Var data_id) data_id (default_alt ++ the_alts)
- mk_result result_id = mkVarApps (mkVarApps (Var result_id) field_tyvars) field_dict_ids
+ mk_result poly_result = mkVarApps (mkVarApps poly_result field_tyvars) field_dict_ids
-- We pull the field lambdas to the top, so we need to
-- apply them in the body. For example:
-- data T = MkT { foo :: forall a. a->a }
Nothing -> Nothing
Just the_arg_id -> Just (mkReboxingAlt uniqs data_con arg_ids body)
where
- body = mk_result the_arg_id
+ body = mk_result (Var the_arg_id)
where
arg_ids = mkTemplateLocalsNum field_base (dataConOrigArgTys data_con)
-- No need to instantiate; same tyvars in datacon as tycon
Selecting a field for a dictionary. If there is just one field, then
there's nothing to do.
-ToDo: unify with mkRecordSelId.
+Dictionary selectors may get nested forall-types. Thus:
+
+ class Foo a where
+ op :: forall b. Ord b => a -> b -> b
+
+Then the top-level type for op is
+
+ op :: forall a. Foo a =>
+ forall b. Ord b =>
+ a -> b -> b
+
+This is unlike ordinary record selectors, which have all the for-alls
+at the outside. When dealing with classes it's very convenient to
+recover the original type signature from the class op selector.
\begin{code}
mkDictSelId :: Name -> Class -> Id
mkDictSelId name clas
- = mkGlobalId (RecordSelId field_lbl) name sel_ty info
+ = mkGlobalId (ClassOpId clas) name sel_ty info
where
sel_ty = mkForAllTys tyvars (mkFunTy (idType dict_id) (idType the_arg_id))
-- We can't just say (exprType rhs), because that would give a type
that they aren't discarded by the occurrence analyser.
\begin{code}
-mkDefaultMethodId dm_name ty = mkVanillaGlobal dm_name ty noCafIdInfo
+mkDefaultMethodId dm_name ty
+ = setIdLocalExported (mkLocalId dm_name ty)
mkDictFunId :: Name -- Name to use for the dict fun;
-> [TyVar]
-> Id
mkDictFunId dfun_name inst_tyvars dfun_theta clas inst_tys
- = mkVanillaGlobal dfun_name dfun_ty noCafIdInfo
+ = setIdLocalExported (mkLocalId dfun_name dfun_ty)
where
dfun_ty = mkSigmaTy inst_tyvars dfun_theta (mkDictTy clas inst_tys)
info = noCafIdInfo `setUnfoldingInfo` mkCompulsoryUnfolding rhs
- ty = mkForAllTys [alphaTyVar,betaTyVar]
- (mkFunTy alphaTy (mkFunTy betaTy betaTy))
- [x,y] = mkTemplateLocals [alphaTy, betaTy]
- rhs = mkLams [alphaTyVar,betaTyVar,x,y] (Case (Var x) x [(DEFAULT, [], Var y)])
+ ty = mkForAllTys [alphaTyVar,openBetaTyVar]
+ (mkFunTy alphaTy (mkFunTy openBetaTy openBetaTy))
+ [x,y] = mkTemplateLocals [alphaTy, openBetaTy]
+ rhs = mkLams [alphaTyVar,openBetaTyVar,x,y] (Case (Var x) x [(DEFAULT, [], Var y)])
-- lazy :: forall a?. a? -> a? (i.e. works for unboxed types too)
-- Used to lazify pseq: pseq a b = a `seq` lazy b
[x] = mkTemplateLocals [openAlphaTy]
\end{code}
-@getTag#@ is another function which can't be defined in Haskell. It needs to
-evaluate its argument and call the dataToTag# primitive.
-
-\begin{code}
-getTagId
- = pcMiscPrelId getTagName ty info
- where
- info = noCafIdInfo `setUnfoldingInfo` mkCompulsoryUnfolding rhs
- -- We don't provide a defn for this; you must inline it
-
- ty = mkForAllTys [alphaTyVar] (mkFunTy alphaTy intPrimTy)
- [x,y] = mkTemplateLocals [alphaTy,alphaTy]
- rhs = mkLams [alphaTyVar,x] $
- Case (Var x) y [ (DEFAULT, [], mkApps (Var dataToTagId) [Type alphaTy, Var y]) ]
-
-dataToTagId = mkPrimOpId DataToTagOp
-\end{code}
-
@realWorld#@ used to be a magic literal, \tr{void#}. If things get
nasty as-is, change it back to a literal (@Literal@).
pc_bottoming_Id name ty
= pcMiscPrelId name ty bottoming_info
where
- bottoming_info = hasCafIdInfo `setAllStrictnessInfo` Just strict_sig
+ bottoming_info = vanillaIdInfo `setAllStrictnessInfo` Just strict_sig
-- Do *not* mark them as NoCafRefs, because they can indeed have
-- CAF refs. For example, pAT_ERROR_ID calls GHC.Err.untangle,
-- which has some CAFs
projects / ghc-hetmet.git / blobdiff