dcOrigArgTys :: [Type], -- Original argument types
-- (before unboxing and flattening of strict fields)
dcOrigResTy :: Type, -- Original result type, as seen by the user
- -- INVARIANT: mentions only dcUnivTyVars
-- NB: for a data instance, the original user result type may
-- differ from the DataCon's representation TyCon. Example
-- data instance T [a] where MkT :: a -> T [a]
-- | Extract the type for any given labelled field of the 'DataCon'
dataConFieldType :: DataCon -> FieldLabel -> Type
-dataConFieldType con label = expectJust "unexpected label" $
- lookup label (dcFields con `zip` dcOrigArgTys con)
+dataConFieldType con label
+ = case lookup label (dcFields con `zip` dcOrigArgTys con) of
+ Just ty -> ty
+ Nothing -> pprPanic "dataConFieldType" (ppr con <+> ppr label)
-- | The strictness markings decided on by the compiler. Does not include those for
-- existential dictionaries. The list is in one-to-one correspondence with the arity of the 'DataCon'
--
-- rather than:
--
--- > T :: forall a c. forall b. (c=[a]) => a -> b -> T c
+-- > T :: forall a c. forall b. (c~[a]) => a -> b -> T c
--
-- NB: If the constructor is part of a data instance, the result type
-- mentions the family tycon, not the internal one.
-- ** Simple construction
mkGlobalId, mkVanillaGlobal, mkVanillaGlobalWithInfo,
- mkLocalId, mkLocalIdWithInfo,
+ mkLocalId, mkLocalIdWithInfo, mkExportedLocalId,
mkSysLocal, mkSysLocalM, mkUserLocal, mkUserLocalM,
mkTemplateLocals, mkTemplateLocalsNum, mkTemplateLocal,
- mkWorkerId, mkExportedLocalId,
+ mkWorkerId,
-- ** Taking an Id apart
- idName, idType, idUnique, idInfo,
- isId, globalIdDetails, idPrimRep,
+ idName, idType, idUnique, idInfo, idDetails,
+ isId, idPrimRep,
recordSelectorFieldLabel,
-- ** Modifying an Id
import IdInfo
import BasicTypes
+
+-- Imported and re-exported
+import Var( Id, DictId,
+ idInfo, idDetails, globaliseId,
+ isId, isLocalId, isGlobalId, isExportedId )
import qualified Var
-import Var
+
import TyCon
import Type
import TcType
idName = Var.varName
idUnique :: Id -> Unique
-idUnique = varUnique
+idUnique = Var.varUnique
idType :: Id -> Kind
-idType = varType
-
-idInfo :: Id -> IdInfo
-idInfo = varIdInfo
+idType = Var.varType
idPrimRep :: Id -> PrimRep
idPrimRep id = typePrimRep (idType id)
-globalIdDetails :: Id -> GlobalIdDetails
-globalIdDetails = globalIdVarDetails
-
-
setIdName :: Id -> Name -> Id
-setIdName = setVarName
+setIdName = Var.setVarName
setIdUnique :: Id -> Unique -> Id
-setIdUnique = setVarUnique
+setIdUnique = Var.setVarUnique
-- | Not only does this set the 'Id' 'Type', it also evaluates the type to try and
-- reduce space usage
setIdType id ty = seqType ty `seq` Var.setVarType id ty
setIdExported :: Id -> Id
-setIdExported = setIdVarExported
+setIdExported = Var.setIdExported
setIdNotExported :: Id -> Id
-setIdNotExported = setIdVarNotExported
+setIdNotExported = Var.setIdNotExported
localiseId :: Id -> Id
-- Make an with the same unique and type as the
where
name = idName id
-globaliseId :: GlobalIdDetails -> Id -> Id
-globaliseId = globaliseIdVar
-
lazySetIdInfo :: Id -> IdInfo -> Id
-lazySetIdInfo = lazySetVarIdInfo
+lazySetIdInfo = Var.lazySetIdInfo
setIdInfo :: Id -> IdInfo -> Id
setIdInfo id info = seqIdInfo info `seq` (lazySetIdInfo id info)
\begin{code}
-- | For an explanation of global vs. local 'Id's, see "Var#globalvslocal"
-mkGlobalId :: GlobalIdDetails -> Name -> Type -> IdInfo -> Id
-mkGlobalId = mkGlobalIdVar
+mkGlobalId :: IdDetails -> Name -> Type -> IdInfo -> Id
+mkGlobalId = Var.mkGlobalVar
-- | Make a global 'Id' without any extra information at all
mkVanillaGlobal :: Name -> Type -> Id
-- | Make a global 'Id' with no global information but some generic 'IdInfo'
mkVanillaGlobalWithInfo :: Name -> Type -> IdInfo -> Id
-mkVanillaGlobalWithInfo = mkGlobalId VanillaGlobal
+mkVanillaGlobalWithInfo = mkGlobalId VanillaId
-- | For an explanation of global vs. local 'Id's, see "Var#globalvslocal"
mkLocalId name ty = mkLocalIdWithInfo name ty vanillaIdInfo
mkLocalIdWithInfo :: Name -> Type -> IdInfo -> Id
-mkLocalIdWithInfo = mkLocalIdVar
+mkLocalIdWithInfo name ty info = Var.mkLocalVar VanillaId name ty info
-- Note [Free type variables]
--- | Create a local 'Id' that is marked as exported. This prevents things attached to it from being removed as dead code.
+-- | Create a local 'Id' that is marked as exported.
+-- This prevents things attached to it from being removed as dead code.
mkExportedLocalId :: Name -> Type -> Id
-mkExportedLocalId name ty = mkExportedLocalIdVar name ty vanillaIdInfo
+mkExportedLocalId name ty = Var.mkExportedLocalVar VanillaId name ty vanillaIdInfo
-- Note [Free type variables]
--- | Create a system local 'Id'. These are local 'Id's (see "Var#globalvslocal") that are created by the compiler out of thin air
+-- | Create a system local 'Id'. These are local 'Id's (see "Var#globalvslocal")
+-- that are created by the compiler out of thin air
mkSysLocal :: FastString -> Unique -> Type -> Id
mkSysLocal fs uniq ty = mkLocalId (mkSystemVarName uniq fs) ty
%************************************************************************
%* *
-\subsection{Basic predicates on @Id@s}
-%* *
-%************************************************************************
-
-\begin{code}
-isId :: Id -> Bool
-isId = isIdVar
-
--- | For an explanation of global vs. local 'Id's, see "Var#globalvslocal"
-isLocalId :: Id -> Bool
-isLocalId = isLocalIdVar
-
--- | For an explanation of global vs. local 'Id's, see "Var#globalvslocal"
-isGlobalId :: Id -> Bool
-isGlobalId = isGlobalIdVar
-
--- | Determines whether an 'Id' is marked as exported and hence will not be considered dead code
-isExportedId :: Id -> Bool
-isExportedId = isExportedIdVar
-\end{code}
-
-%************************************************************************
-%* *
\subsection{Special Ids}
%* *
%************************************************************************
-- | If the 'Id' is that for a record selector, extract the 'sel_tycon' and label. Panic otherwise
recordSelectorFieldLabel :: Id -> (TyCon, FieldLabel)
recordSelectorFieldLabel id
- = case globalIdDetails id of
- RecordSelId { sel_tycon = tycon, sel_label = lbl } -> (tycon,lbl)
+ = case Var.idDetails id of
+ RecSelId { sel_tycon = tycon } -> (tycon, idName id)
_ -> panic "recordSelectorFieldLabel"
isRecordSelector :: Id -> Bool
isFCallId_maybe :: Id -> Maybe ForeignCall
isDataConWorkId_maybe :: Id -> Maybe DataCon
-isRecordSelector id = case globalIdDetails id of
- RecordSelId {} -> True
+isRecordSelector id = case Var.idDetails id of
+ RecSelId {} -> True
_ -> False
-isNaughtyRecordSelector id = case globalIdDetails id of
- RecordSelId { sel_naughty = n } -> n
+isNaughtyRecordSelector id = case Var.idDetails id of
+ RecSelId { sel_naughty = n } -> n
_ -> False
-isClassOpId_maybe id = case globalIdDetails id of
+isClassOpId_maybe id = case Var.idDetails id of
ClassOpId cls -> Just cls
_other -> Nothing
-isPrimOpId id = case globalIdDetails id of
+isPrimOpId id = case Var.idDetails id of
PrimOpId _ -> True
_ -> False
-isPrimOpId_maybe id = case globalIdDetails id of
+isPrimOpId_maybe id = case Var.idDetails id of
PrimOpId op -> Just op
_ -> Nothing
-isFCallId id = case globalIdDetails id of
+isFCallId id = case Var.idDetails id of
FCallId _ -> True
_ -> False
-isFCallId_maybe id = case globalIdDetails id of
+isFCallId_maybe id = case Var.idDetails id of
FCallId call -> Just call
_ -> Nothing
-isDataConWorkId id = case globalIdDetails id of
+isDataConWorkId id = case Var.idDetails id of
DataConWorkId _ -> True
_ -> False
-isDataConWorkId_maybe id = case globalIdDetails id of
+isDataConWorkId_maybe id = case Var.idDetails id of
DataConWorkId con -> Just con
_ -> Nothing
isDataConId_maybe :: Id -> Maybe DataCon
-isDataConId_maybe id = case globalIdDetails id of
+isDataConId_maybe id = case Var.idDetails id of
DataConWorkId con -> Just con
DataConWrapId con -> Just con
_ -> Nothing
-- they aren't any more. Instead, we inject a binding for
-- them at the CorePrep stage.
-- EXCEPT: unboxed tuples, which definitely have no binding
-hasNoBinding id = case globalIdDetails id of
+hasNoBinding id = case Var.idDetails id of
PrimOpId _ -> True -- See Note [Primop wrappers]
FCallId _ -> True
DataConWorkId dc -> isUnboxedTupleCon dc
-- declarations, so we don't need to put its signature in an interface
-- file, even if it's mentioned in some other interface unfolding.
isImplicitId id
- = case globalIdDetails id of
- RecordSelId {} -> True
+ = case Var.idDetails id of
FCallId _ -> True
+ ClassOpId _ -> True
PrimOpId _ -> True
- ClassOpId _ -> True
DataConWorkId _ -> True
DataConWrapId _ -> True
-- These are are implied by their type or class decl;
\begin{code}
isTickBoxOp :: Id -> Bool
isTickBoxOp id =
- case globalIdDetails id of
+ case Var.idDetails id of
TickBoxOpId _ -> True
_ -> False
isTickBoxOp_maybe :: Id -> Maybe TickBoxOp
isTickBoxOp_maybe id =
- case globalIdDetails id of
+ case Var.idDetails id of
TickBoxOpId tick -> Just tick
_ -> Nothing
\end{code}
\begin{code}
module IdInfo (
- -- * The GlobalIdDetails type
- GlobalIdDetails(..), notGlobalId, -- Not abstract
+ -- * The IdDetails type
+ IdDetails(..), pprIdDetails,
-- * The IdInfo type
IdInfo, -- Abstract
%************************************************************************
%* *
-\subsection{GlobalIdDetails}
+ IdDetails
%* *
%************************************************************************
-This type is here (rather than in Id.lhs) mainly because there's
-an IdInfo.hi-boot, but no Id.hi-boot, and GlobalIdDetails is imported
-(recursively) by Var.lhs.
-
\begin{code}
--- | Information pertaining to global 'Id's. See "Var#globalvslocal" for the distinction
--- between global and local in this context
-data GlobalIdDetails
- = VanillaGlobal -- ^ The 'Id' is imported from elsewhere or is a default method 'Id'
+-- | The 'IdDetails' of an 'Id' give stable, and necessary,
+-- information about the Id.
+data IdDetails
+ = VanillaId
-- | The 'Id' for a record selector
- | RecordSelId
+ | RecSelId
{ sel_tycon :: TyCon -- ^ For a data type family, this is the /instance/ 'TyCon'
-- not the family 'TyCon'
- , sel_label :: FieldLabel
, sel_naughty :: Bool -- True <=> a "naughty" selector which can't actually exist, for example @x@ in:
- --
- -- > data T = forall a. MkT { x :: a }
- }
- -- See Note [Naughty record selectors]
- -- with MkId.mkRecordSelectorId
+ -- data T = forall a. MkT { x :: a }
+ } -- See Note [Naughty record selectors] in TcTyClsDecls
| DataConWorkId DataCon -- ^ The 'Id' is for a data constructor /worker/
| DataConWrapId DataCon -- ^ The 'Id' is for a data constructor /wrapper/
| TickBoxOpId TickBoxOp -- ^ The 'Id' is for a HPC tick box (both traditional and binary)
- | NotGlobalId -- ^ Used as a convenient extra return value from 'globalIdDetails'
-
--- | An entirely unhelpful 'GlobalIdDetails'
-notGlobalId :: GlobalIdDetails
-notGlobalId = NotGlobalId
-
-instance Outputable GlobalIdDetails where
- ppr NotGlobalId = ptext (sLit "[***NotGlobalId***]")
- ppr VanillaGlobal = ptext (sLit "[GlobalId]")
- ppr (DataConWorkId _) = ptext (sLit "[DataCon]")
- ppr (DataConWrapId _) = ptext (sLit "[DataConWrapper]")
- ppr (ClassOpId _) = ptext (sLit "[ClassOp]")
- ppr (PrimOpId _) = ptext (sLit "[PrimOp]")
- ppr (FCallId _) = ptext (sLit "[ForeignCall]")
- ppr (TickBoxOpId _) = ptext (sLit "[TickBoxOp]")
- ppr (RecordSelId {}) = ptext (sLit "[RecSel]")
+ | DFunId -- ^ A dictionary function. We don't use this in an essential way,
+ -- currently, but it's kind of nice that we can keep track of
+ -- which Ids are DFuns, across module boundaries too
+
+
+instance Outputable IdDetails where
+ ppr = pprIdDetails
+
+pprIdDetails :: IdDetails -> SDoc
+pprIdDetails VanillaId = empty
+pprIdDetails (RecSelId {}) = ptext (sLit "[RecSel]")
+pprIdDetails (DataConWorkId _) = ptext (sLit "[DataCon]")
+pprIdDetails (DataConWrapId _) = ptext (sLit "[DataConWrapper]")
+pprIdDetails (ClassOpId _) = ptext (sLit "[ClassOp]")
+pprIdDetails (PrimOpId _) = ptext (sLit "[PrimOp]")
+pprIdDetails (FCallId _) = ptext (sLit "[ForeignCall]")
+pprIdDetails (TickBoxOpId _) = ptext (sLit "[TickBoxOp]")
+pprIdDetails DFunId = ptext (sLit "[DFunId]")
\end{code}
+
+
%************************************************************************
%* *
\subsection{The main IdInfo type}
\begin{code}
module IdInfo where
-
+import Outputable
data IdInfo
-data GlobalIdDetails
+data IdDetails
-notGlobalId :: GlobalIdDetails
-seqIdInfo :: IdInfo -> ()
+pprIdDetails :: IdDetails -> SDoc
\end{code}
\ No newline at end of file
mkDictSelId,
mkDataConIds,
- mkRecordSelId,
mkPrimOpId, mkFCallId, mkTickBoxOpId, mkBreakPointOpId,
mkReboxingAlt, wrapNewTypeBody, unwrapNewTypeBody,
mkRuntimeErrorApp,
rEC_CON_ERROR_ID, iRREFUT_PAT_ERROR_ID, rUNTIME_ERROR_ID,
nON_EXHAUSTIVE_GUARDS_ERROR_ID, nO_METHOD_BINDING_ERROR_ID,
- pAT_ERROR_ID, eRROR_ID,
+ pAT_ERROR_ID, eRROR_ID, rEC_SEL_ERROR_ID,
unsafeCoerceName
) where
import TysPrim
import TysWiredIn
import PrelRules
-import Unify
import Type
import TypeRep
import Coercion
import ForeignCall
import DataCon
import Id
-import Var ( Var, TyVar, mkCoVar)
+import Var ( Var, TyVar, mkCoVar, mkExportedLocalVar )
import IdInfo
import NewDemand
-import DmdAnal
import CoreSyn
import Unique
import Maybes
nO_METHOD_BINDING_ERROR_ID,
pAT_ERROR_ID,
rEC_CON_ERROR_ID,
+ rEC_SEL_ERROR_ID,
lazyId
] ++ ghcPrimIds
nt_work_info = noCafIdInfo -- The NoCaf-ness is set by noCafIdInfo
`setArityInfo` 1 -- Arity 1
`setUnfoldingInfo` newtype_unf
- newtype_unf = -- The assertion below is no longer correct:
- -- there may be a dict theta rather than a singleton orig_arg_ty
- -- ASSERT( isVanillaDataCon data_con &&
- -- isSingleton orig_arg_tys )
- --
- -- No existentials on a newtype, but it can have a context
- -- e.g. newtype Eq a => T a = MkT (...)
+ id_arg1 = mkTemplateLocal 1 (head orig_arg_tys)
+ newtype_unf = ASSERT2( isVanillaDataCon data_con &&
+ isSingleton orig_arg_tys, ppr data_con )
+ -- Note [Newtype datacons]
mkCompulsoryUnfolding $
mkLams wrap_tvs $ Lam id_arg1 $
- wrapNewTypeBody tycon res_ty_args
- (Var id_arg1)
+ wrapNewTypeBody tycon res_ty_args (Var id_arg1)
- id_arg1 = mkTemplateLocal 1
- (if null orig_arg_tys
- then ASSERT(not (null $ dataConDictTheta data_con))
- mkPredTy $ head (dataConDictTheta data_con)
- else head orig_arg_tys
- )
----------- Wrapper --------------
-- We used to include the stupid theta in the wrapper's args
n = length tys
\end{code}
+Note [Newtype datacons]
+~~~~~~~~~~~~~~~~~~~~~~~
+The "data constructor" for a newtype should always be vanilla. At one
+point this wasn't true, because the newtype arising from
+ class C a => D a
+looked like
+ newtype T:D a = D:D (C a)
+so the data constructor for T:C had a single argument, namely the
+predicate (C a). But now we treat that as an ordinary argument, not
+part of the theta-type, so all is well.
+
%************************************************************************
%* *
-\subsection{Record selectors}
+\subsection{Dictionary selectors}
%* *
%************************************************************************
-We're going to build a record selector unfolding that looks like this:
-
- data T a b c = T1 { ..., op :: a, ...}
- | T2 { ..., op :: a, ...}
- | T3
-
- sel = /\ a b c -> \ d -> case d of
- T1 ... x ... -> x
- T2 ... x ... -> x
- other -> error "..."
-
-Similarly for newtypes
-
- newtype N a = MkN { unN :: a->a }
-
- unN :: N a -> a -> a
- unN n = coerce (a->a) n
-
-We need to take a little care if the field has a polymorphic type:
-
- data R = R { f :: forall a. a->a }
-
-Then we want
-
- f :: forall a. R -> a -> a
- f = /\ a \ r = case r of
- R f -> f a
-
-(not f :: R -> forall a. a->a, which gives the type inference mechanism
-problems at call sites)
-
-Similarly for (recursive) newtypes
-
- newtype N = MkN { unN :: forall a. a->a }
-
- unN :: forall b. N -> b -> b
- unN = /\b -> \n:N -> (coerce (forall a. a->a) n)
-
+Selecting a field for a dictionary. If there is just one field, then
+there's nothing to do.
-Note [Naughty record selectors]
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-A "naughty" field is one for which we can't define a record
-selector, because an existential type variable would escape. For example:
- data T = forall a. MkT { x,y::a }
-We obviously can't define
- x (MkT v _) = v
-Nevertheless we *do* put a RecordSelId into the type environment
-so that if the user tries to use 'x' as a selector we can bleat
-helpfully, rather than saying unhelpfully that 'x' is not in scope.
-Hence the sel_naughty flag, to identify record selectors that don't really exist.
+Dictionary selectors may get nested forall-types. Thus:
-In general, a field is naughty if its type mentions a type variable that
-isn't in the result type of the constructor.
+ class Foo a where
+ op :: forall b. Ord b => a -> b -> b
-Note [GADT record selectors]
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-For GADTs, we require that all constructors with a common field 'f' have the same
-result type (modulo alpha conversion). [Checked in TcTyClsDecls.checkValidTyCon]
-E.g.
- data T where
- T1 { f :: Maybe a } :: T [a]
- T2 { f :: Maybe a, y :: b } :: T [a]
+Then the top-level type for op is
-and now the selector takes that result type as its argument:
- f :: forall a. T [a] -> Maybe a
+ op :: forall a. Foo a =>
+ forall b. Ord b =>
+ a -> b -> b
-Details: the "real" types of T1,T2 are:
- T1 :: forall r a. (r~[a]) => a -> T r
- T2 :: forall r a b. (r~[a]) => a -> b -> T r
+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.
-So the selector loooks like this:
- f :: forall a. T [a] -> Maybe a
- f (a:*) (t:T [a])
- = case t of
- T1 c (g:[a]~[c]) (v:Maybe c) -> v `cast` Maybe (right (sym g))
- T2 c d (g:[a]~[c]) (v:Maybe c) (w:d) -> v `cast` Maybe (right (sym g))
+\begin{code}
+mkDictSelId :: Bool -- True <=> don't include the unfolding
+ -- Little point on imports without -O, because the
+ -- dictionary itself won't be visible
+ -> Name -> Class -> Id
+mkDictSelId no_unf name clas
+ = 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
+ -- C a -> C a
+ -- for a single-op class (after all, the selector is the identity)
+ -- But it's type must expose the representation of the dictionary
+ -- to get (say) C a -> (a -> a)
-Note the forall'd tyvars of the selector are just the free tyvars
-of the result type; there may be other tyvars in the constructor's
-type (e.g. 'b' in T2).
+ info = noCafIdInfo
+ `setArityInfo` 1
+ `setAllStrictnessInfo` Just strict_sig
+ `setUnfoldingInfo` (if no_unf then noUnfolding
+ else mkImplicitUnfolding rhs)
-Note the need for casts in the result!
+ -- We no longer use 'must-inline' on record selectors. They'll
+ -- inline like crazy if they scrutinise a constructor
-Note [Selector running example]
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-It's OK to combine GADTs and type families. Here's a running example:
+ -- The strictness signature is of the form U(AAAVAAAA) -> T
+ -- where the V depends on which item we are selecting
+ -- It's worth giving one, so that absence info etc is generated
+ -- even if the selector isn't inlined
+ strict_sig = mkStrictSig (mkTopDmdType [arg_dmd] TopRes)
+ arg_dmd | isNewTyCon tycon = evalDmd
+ | otherwise = Eval (Prod [ if the_arg_id == id then evalDmd else Abs
+ | id <- arg_ids ])
- data instance T [a] where
- T1 { fld :: b } :: T [Maybe b]
+ tycon = classTyCon clas
+ [data_con] = tyConDataCons tycon
+ tyvars = dataConUnivTyVars data_con
+ arg_tys = {- ASSERT( isVanillaDataCon data_con ) -} dataConRepArgTys data_con
+ eq_theta = dataConEqTheta data_con
+ the_arg_id = assoc "MkId.mkDictSelId" (map idName (classSelIds clas) `zip` arg_ids) name
-The representation type looks like this
- data :R7T a where
- T1 { fld :: b } :: :R7T (Maybe b)
+ pred = mkClassPred clas (mkTyVarTys tyvars)
+ dict_id = mkTemplateLocal 1 $ mkPredTy pred
+ (eq_ids,n) = mkCoVarLocals 2 $ mkPredTys eq_theta
+ arg_ids = mkTemplateLocalsNum n arg_tys
-and there's coercion from the family type to the representation type
- :CoR7T a :: T [a] ~ :R7T a
+ mkCoVarLocals i [] = ([],i)
+ mkCoVarLocals i (x:xs) = let (ys,j) = mkCoVarLocals (i+1) xs
+ y = mkCoVar (mkSysTvName (mkBuiltinUnique i) (fsLit "dc_co")) x
+ in (y:ys,j)
-The selector we want for fld looks like this:
+ rhs = mkLams tyvars (Lam dict_id rhs_body)
+ rhs_body | isNewTyCon tycon = unwrapNewTypeBody tycon (map mkTyVarTy tyvars) (Var dict_id)
+ | otherwise = Case (Var dict_id) dict_id (idType the_arg_id)
+ [(DataAlt data_con, eq_ids ++ arg_ids, Var the_arg_id)]
+\end{code}
- fld :: forall b. T [Maybe b] -> b
- fld = /\b. \(d::T [Maybe b]).
- case d `cast` :CoR7T (Maybe b) of
- T1 (x::b) -> x
-The scrutinee of the case has type :R7T (Maybe b), which can be
-gotten by appying the eq_spec to the univ_tvs of the data con.
+%************************************************************************
+%* *
+ Boxing and unboxing
+%* *
+%************************************************************************
\begin{code}
-mkRecordSelId :: TyCon -> FieldLabel -> Id
-mkRecordSelId tycon field_label
- -- Assumes that all fields with the same field label have the same type
- = sel_id
- where
- -- Because this function gets called by implicitTyThings, we need to
- -- produce the OccName of the Id without doing any suspend type checks.
- -- (see the note [Tricky iface loop]).
- -- A suspended type-check is sometimes necessary to compute field_ty,
- -- so we need to make sure that we suspend anything that depends on field_ty.
-
- -- the overall result
- sel_id = mkGlobalId sel_id_details field_label theType theInfo
-
- -- check whether the type is naughty: this thunk does not get forced
- -- until the type is actually needed
- field_ty = dataConFieldType con1 field_label
- is_naughty = not (tyVarsOfType field_ty `subVarSet` data_tv_set)
-
- -- it's important that this doesn't force the if
- (theType, theInfo) = if is_naughty
- -- Escapist case here for naughty constructors
- -- We give it no IdInfo, and a type of
- -- forall a.a (never looked at)
- then (forall_a_a, noCafIdInfo)
- -- otherwise do the real case
- else (selector_ty, info)
-
- sel_id_details = RecordSelId { sel_tycon = tycon,
- sel_label = field_label,
- sel_naughty = is_naughty }
- -- For a data type family, the tycon is the *instance* TyCon
-
- -- for naughty case
- forall_a_a = mkForAllTy alphaTyVar (mkTyVarTy alphaTyVar)
-
- -- real case starts here:
- data_cons = tyConDataCons tycon
- data_cons_w_field = filter has_field data_cons -- Can't be empty!
- has_field con = field_label `elem` dataConFieldLabels con
-
- con1 = ASSERT( not (null data_cons_w_field) ) head data_cons_w_field
- (univ_tvs, _, eq_spec, _, _, _, data_ty) = dataConFullSig con1
- -- For a data type family, the data_ty (and hence selector_ty) mentions
- -- only the family TyCon, not the instance TyCon
- data_tv_set = tyVarsOfType data_ty
- data_tvs = varSetElems data_tv_set
-
- -- _Very_ tiresomely, the selectors are (unnecessarily!) overloaded over
- -- just the dictionaries in the types of the constructors that contain
- -- the relevant field. [The Report says that pattern matching on a
- -- constructor gives the same constraints as applying it.] Urgh.
- --
- -- However, not all data cons have all constraints (because of
- -- BuildTyCl.mkDataConStupidTheta). So we need to find all the data cons
- -- involved in the pattern match and take the union of their constraints.
- stupid_dict_tys = mkPredTys (dataConsStupidTheta data_cons_w_field)
- n_stupid_dicts = length stupid_dict_tys
-
- (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
- -- be a bit careful. Suppose we have
- -- data R = R { op :: forall a. Foo a => a -> a }
- -- Then we can't give op the type
- -- op :: R -> forall a. Foo a => a -> a
- -- because the typechecker doesn't understand foralls to the
- -- right of an arrow. The "right" type to give it is
- -- op :: forall a. Foo a => R -> a -> a
- -- But then we must generate the right unfolding too:
- -- op = /\a -> \dfoo -> \ r ->
- -- case r of
- -- R op -> op a dfoo
- -- Note that this is exactly the type we'd infer from a user defn
- -- op (R op) = op
-
- selector_ty :: Type
- selector_ty = mkForAllTys data_tvs $ mkForAllTys field_tyvars $
- mkFunTys stupid_dict_tys $ mkFunTys field_dict_tys $
- mkFunTy data_ty field_tau
-
- arity = 1 + n_stupid_dicts + n_field_dict_tys
-
- (strict_sig, rhs_w_str) = dmdAnalTopRhs sel_rhs
- -- Use the demand analyser to work out strictness.
- -- With all this unpackery it's not easy!
-
- info = noCafIdInfo
- `setCafInfo` caf_info
- `setArityInfo` arity
- `setUnfoldingInfo` unfolding
- `setAllStrictnessInfo` Just strict_sig
-
- unfolding = mkImplicitUnfolding rhs_w_str
-
- -- Allocate Ids. We do it a funny way round because field_dict_tys is
- -- almost always empty. Also note that we use max_dict_tys
- -- rather than n_dict_tys, because the latter gives an infinite loop:
- -- n_dict tys depends on the_alts, which depens on arg_ids, which
- -- depends on arity, which depends on n_dict tys. Sigh! Mega sigh!
- stupid_dict_ids = mkTemplateLocalsNum 1 stupid_dict_tys
- max_stupid_dicts = length (tyConStupidTheta tycon)
- field_dict_base = max_stupid_dicts + 1
- field_dict_ids = mkTemplateLocalsNum field_dict_base field_dict_tys
- dict_id_base = field_dict_base + n_field_dict_tys
- data_id = mkTemplateLocal dict_id_base data_ty
- scrut_id = mkTemplateLocal (dict_id_base+1) scrut_ty
- arg_base = dict_id_base + 2
-
- the_alts :: [CoreAlt]
- the_alts = map mk_alt data_cons_w_field -- Already sorted by data-con
- no_default = length data_cons == length data_cons_w_field -- No default needed
-
- default_alt | no_default = []
- | otherwise = [(DEFAULT, [], error_expr)]
-
- -- The default branch may have CAF refs, because it calls recSelError etc.
- caf_info | no_default = NoCafRefs
- | otherwise = MayHaveCafRefs
-
- sel_rhs = mkLams data_tvs $ mkLams field_tyvars $
- mkLams stupid_dict_ids $ mkLams field_dict_ids $
- Lam data_id $ mk_result sel_body
-
- scrut_ty_args = substTyVars (mkTopTvSubst eq_spec) univ_tvs
- scrut_ty = mkTyConApp tycon scrut_ty_args
- scrut = unwrapFamInstScrut tycon scrut_ty_args (Var data_id)
- -- First coerce from the type family to the representation type
-
- -- NB: A newtype always has a vanilla DataCon; no existentials etc
- -- data_tys will simply be the dataConUnivTyVars
- sel_body | isNewTyCon tycon = unwrapNewTypeBody tycon scrut_ty_args scrut
- | otherwise = Case scrut scrut_id field_ty (default_alt ++ the_alts)
-
- 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 }
- --
- -- foo :: forall a. T -> a -> a
- -- foo = /\a. \t:T. case t of { MkT f -> f a }
-
- mk_alt data_con
- = mkReboxingAlt rebox_uniqs data_con (ex_tvs ++ co_tvs ++ arg_vs) rhs
- where
- -- get pattern binders with types appropriately instantiated
- arg_uniqs = map mkBuiltinUnique [arg_base..]
- (ex_tvs, co_tvs, arg_vs) = dataConOrigInstPat arg_uniqs data_con
- scrut_ty_args
-
- 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))
-
- -- Generate the cast for the result
- -- See Note [GADT record selectors] for why a cast is needed
- in_scope_tvs = ex_tvs ++ co_tvs ++ data_tvs
- reft = matchRefine in_scope_tvs (map (mkSymCoercion . mkTyVarTy) co_tvs)
- rhs = case refineType reft (idType the_arg_id) of
- Nothing -> Var the_arg_id
- Just (co, data_ty) -> ASSERT2( data_ty `tcEqType` field_ty,
- ppr data_con $$ ppr data_ty $$ ppr field_ty )
- Cast (Var the_arg_id) co
-
- 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_ty full_msg
- full_msg = showSDoc (sep [text "No match in record selector", ppr sel_id])
-
-- unbox a product type...
-- we will recurse into newtypes, casting along the way, and unbox at the
-- first product data constructor we find. e.g.
%************************************************************************
%* *
-\subsection{Dictionary selectors}
-%* *
-%************************************************************************
-
-Selecting a field for a dictionary. If there is just one field, then
-there's nothing to do.
-
-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 :: Bool -- True <=> don't include the unfolding
- -- Little point on imports without -O, because the
- -- dictionary itself won't be visible
- -> Name -> Class -> Id
-mkDictSelId no_unf name clas
- = 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
- -- C a -> C a
- -- for a single-op class (after all, the selector is the identity)
- -- But it's type must expose the representation of the dictionary
- -- to get (say) C a -> (a -> a)
-
- info = noCafIdInfo
- `setArityInfo` 1
- `setAllStrictnessInfo` Just strict_sig
- `setUnfoldingInfo` (if no_unf then noUnfolding
- else mkImplicitUnfolding rhs)
-
- -- We no longer use 'must-inline' on record selectors. They'll
- -- inline like crazy if they scrutinise a constructor
-
- -- The strictness signature is of the form U(AAAVAAAA) -> T
- -- where the V depends on which item we are selecting
- -- It's worth giving one, so that absence info etc is generated
- -- even if the selector isn't inlined
- strict_sig = mkStrictSig (mkTopDmdType [arg_dmd] TopRes)
- arg_dmd | isNewTyCon tycon = evalDmd
- | otherwise = Eval (Prod [ if the_arg_id == id then evalDmd else Abs
- | id <- arg_ids ])
-
- tycon = classTyCon clas
- [data_con] = tyConDataCons tycon
- tyvars = dataConUnivTyVars data_con
- arg_tys = {- ASSERT( isVanillaDataCon data_con ) -} dataConRepArgTys data_con
- eq_theta = dataConEqTheta data_con
- the_arg_id = assoc "MkId.mkDictSelId" (map idName (classSelIds clas) `zip` arg_ids) name
-
- pred = mkClassPred clas (mkTyVarTys tyvars)
- dict_id = mkTemplateLocal 1 $ mkPredTy pred
- (eq_ids,n) = mkCoVarLocals 2 $ mkPredTys eq_theta
- arg_ids = mkTemplateLocalsNum n arg_tys
-
- mkCoVarLocals i [] = ([],i)
- mkCoVarLocals i (x:xs) = let (ys,j) = mkCoVarLocals (i+1) xs
- y = mkCoVar (mkSysTvName (mkBuiltinUnique i) (fsLit "dc_co")) x
- in (y:ys,j)
-
- rhs = mkLams tyvars (Lam dict_id rhs_body)
- rhs_body | isNewTyCon tycon = unwrapNewTypeBody tycon (map mkTyVarTy tyvars) (Var dict_id)
- | otherwise = Case (Var dict_id) dict_id (idType the_arg_id)
- [(DataAlt data_con, eq_ids ++ arg_ids, Var the_arg_id)]
-\end{code}
-
-
-%************************************************************************
-%* *
Wrapping and unwrapping newtypes and type families
%* *
%************************************************************************
-> Id
mkDictFunId dfun_name inst_tyvars dfun_theta clas inst_tys
- = mkExportedLocalId dfun_name dfun_ty
+ = mkExportedLocalVar DFunId dfun_name dfun_ty vanillaIdInfo
where
dfun_ty = mkSigmaTy inst_tyvars dfun_theta (mkDictTy clas inst_tys)
-
-{- 1 dec 99: disable the Mark Jones optimisation for the sake
- of compatibility with Hugs.
- See `types/InstEnv' for a discussion related to this.
-
- (class_tyvars, sc_theta, _, _) = classBigSig clas
- not_const (clas, tys) = not (isEmptyVarSet (tyVarsOfTypes tys))
- sc_theta' = substClasses (zipTopTvSubst class_tyvars inst_tys) sc_theta
- dfun_theta = case inst_decl_theta of
- [] -> [] -- If inst_decl_theta is empty, then we don't
- -- want to have any dict arguments, so that we can
- -- expose the constant methods.
-
- other -> nub (inst_decl_theta ++ filter not_const sc_theta')
- -- Otherwise we pass the superclass dictionaries to
- -- the dictionary function; the Mark Jones optimisation.
- --
- -- NOTE the "nub". I got caught by this one:
- -- class Monad m => MonadT t m where ...
- -- instance Monad m => MonadT (EnvT env) m where ...
- -- Here, the inst_decl_theta has (Monad m); but so
- -- does the sc_theta'!
- --
- -- NOTE the "not_const". I got caught by this one too:
- -- class Foo a => Baz a b where ...
- -- instance Wob b => Baz T b where..
- -- Now sc_theta' has Foo T
--}
\end{code}
mkRuntimeErrorId name = pc_bottoming_Id name runtimeErrorTy
runtimeErrorTy :: Type
-runtimeErrorTy = mkSigmaTy [openAlphaTyVar] [] (mkFunTy addrPrimTy openAlphaTy)
+runtimeErrorTy = mkSigmaTy [openAlphaTyVar] [] (mkFunTy addrPrimTy openAlphaTy)
\end{code}
\begin{code}
-- * The main data type
Var,
- -- ** Constructing 'Var's
- mkLocalIdVar, mkExportedLocalIdVar, mkGlobalIdVar,
-
-- ** Taking 'Var's apart
- varName, varUnique, varType, varIdInfo, globalIdVarDetails,
+ varName, varUnique, varType,
-- ** Modifying 'Var's
setVarName, setVarUnique, setVarType,
- setIdVarExported, setIdVarNotExported,
- globaliseIdVar, lazySetVarIdInfo,
+
+ -- ** Constructing, taking apart, modifying 'Id's
+ mkGlobalVar, mkLocalVar, mkExportedLocalVar,
+ idInfo, idDetails,
+ lazySetIdInfo, setIdDetails, globaliseId,
+ setIdExported, setIdNotExported,
-- ** Predicates
- isCoVar, isIdVar, isTyVar, isTcTyVar,
- isLocalVar, isLocalIdVar,
- isGlobalIdVar, isExportedIdVar,
+ isCoVar, isId, isTyVar, isTcTyVar,
+ isLocalVar, isLocalId,
+ isGlobalId, isExportedId,
mustHaveLocalBinding,
-- * Type variable data type
import {-# SOURCE #-} TypeRep( Type, Kind )
import {-# SOURCE #-} TcType( TcTyVarDetails, pprTcTyVarDetails )
-import {-# SOURCE #-} IdInfo( GlobalIdDetails, notGlobalId,
- IdInfo )
+import {-# SOURCE #-} IdInfo( IdDetails, IdInfo, pprIdDetails )
import {-# SOURCE #-} TypeRep( isCoercionKind )
import Name hiding (varName)
varType :: Kind,
tcTyVarDetails :: TcTyVarDetails }
- | GlobalId { -- Used for imported Ids, dict selectors etc
- -- See Note [GlobalId/LocalId] below
- varName :: !Name, -- Always an External or WiredIn Name
- realUnique :: FastInt,
- varType :: Type,
- idInfo_ :: IdInfo,
- gblDetails :: GlobalIdDetails }
-
- | LocalId { -- Used for locally-defined Ids
- -- See Note [GlobalId/LocalId] below
+ | Id {
varName :: !Name,
realUnique :: FastInt,
varType :: Type,
- idInfo_ :: IdInfo,
- lclDetails :: LocalIdDetails }
+ idScope :: IdScope,
+ idDetails :: IdDetails, -- Stable, doesn't change
+ idInfo :: IdInfo } -- Unstable, updated by simplifier
-data LocalIdDetails
+data IdScope -- See Note [GlobalId/LocalId]
+ = GlobalId
+ | LocalId ExportFlag
+
+data ExportFlag
= NotExported -- ^ Not exported: may be discarded as dead code.
| Exported -- ^ Exported: kept alive
+
\end{code}
Note [GlobalId/LocalId]
\begin{code}
instance Outputable Var where
- ppr var = ppr (varName var) <+> ifPprDebug (brackets extra)
- where
- extra = case var of
- GlobalId {} -> ptext (sLit "gid")
- LocalId {} -> ptext (sLit "lid")
- TyVar {} -> ptext (sLit "tv")
- TcTyVar {tcTyVarDetails = details} -> pprTcTyVarDetails details
+ ppr var = ppr (varName var) <+> ifPprDebug (brackets (ppr_debug var))
+
+ppr_debug :: Var -> SDoc
+ppr_debug (TyVar {}) = ptext (sLit "tv")
+ppr_debug (TcTyVar {tcTyVarDetails = d}) = pprTcTyVarDetails d
+ppr_debug (Id { idScope = s, idDetails = d }) = ppr_id_scope s <> pprIdDetails d
+
+ppr_id_scope :: IdScope -> SDoc
+ppr_id_scope GlobalId = ptext (sLit "gid")
+ppr_id_scope (LocalId Exported) = ptext (sLit "lidx")
+ppr_id_scope (LocalId NotExported) = ptext (sLit "lid")
instance Show Var where
showsPrec p var = showsPrecSDoc p (ppr var)
setVarType :: Id -> Type -> Id
setVarType id ty = id { varType = ty }
-
-setIdVarExported :: Var -> Var
--- ^ Exports the given local 'Id'. Can also be called on global 'Id's, such as data constructors
--- and class operations, which are born as global 'Id's and automatically exported
-setIdVarExported id@(LocalId {}) = id { lclDetails = Exported }
-setIdVarExported other_id = ASSERT( isIdVar other_id ) other_id
-
-setIdVarNotExported :: Id -> Id
--- ^ We can only do this to LocalIds
-setIdVarNotExported id = ASSERT( isLocalIdVar id ) id { lclDetails = NotExported }
-
-globaliseIdVar :: GlobalIdDetails -> Var -> Var
--- ^ If it's a local, make it global
-globaliseIdVar details id = GlobalId { varName = varName id,
- realUnique = realUnique id,
- varType = varType id,
- idInfo_ = varIdInfo id,
- gblDetails = details }
-
--- | Extract 'Id' information from the 'Var' if it represents a global or local 'Id', otherwise panic
-varIdInfo :: Var -> IdInfo
-varIdInfo (GlobalId {idInfo_ = info}) = info
-varIdInfo (LocalId {idInfo_ = info}) = info
-varIdInfo other_var = pprPanic "idInfo" (ppr other_var)
-
-lazySetVarIdInfo :: Var -> IdInfo -> Var
-lazySetVarIdInfo id info = id { idInfo_ = info }
\end{code}
%************************************************************************
\begin{code}
-
-- These synonyms are here and not in Id because otherwise we need a very
-- large number of SOURCE imports of Id.hs :-(
type Id = Var
type DictId = Var
+-- The next three have a 'Var' suffix even though they always build
+-- Ids, becuase Id.lhs uses 'mkGlobalId' etc with different types
+mkGlobalVar :: IdDetails -> Name -> Type -> IdInfo -> Id
+mkGlobalVar details name ty info
+ = mk_id name ty GlobalId details info
+
+mkLocalVar :: IdDetails -> Name -> Type -> IdInfo -> Id
+mkLocalVar details name ty info
+ = mk_id name ty (LocalId NotExported) details info
+
+-- | Exported 'Var's will not be removed as dead code
+mkExportedLocalVar :: IdDetails -> Name -> Type -> IdInfo -> Id
+mkExportedLocalVar details name ty info
+ = mk_id name ty (LocalId Exported) details info
+
+mk_id :: Name -> Type -> IdScope -> IdDetails -> IdInfo -> Id
+mk_id name ty scope details info
+ = Id { varName = name,
+ realUnique = getKeyFastInt (nameUnique name),
+ varType = ty,
+ idScope = scope,
+ idDetails = details,
+ idInfo = info }
+
+-------------------
+lazySetIdInfo :: Id -> IdInfo -> Var
+lazySetIdInfo id info = id { idInfo = info }
+
+setIdDetails :: Id -> IdDetails -> Id
+setIdDetails id details = id { idDetails = details }
+
+globaliseId :: Id -> Id
+-- ^ If it's a local, make it global
+globaliseId id = id { idScope = GlobalId }
+
+setIdExported :: Id -> Id
+-- ^ Exports the given local 'Id'. Can also be called on global 'Id's, such as data constructors
+-- and class operations, which are born as global 'Id's and automatically exported
+setIdExported id@(Id { idScope = LocalId {} }) = id { idScope = LocalId Exported }
+setIdExported id@(Id { idScope = GlobalId }) = id
+setIdExported tv = pprPanic "setIdExported" (ppr tv)
+
+setIdNotExported :: Id -> Id
+-- ^ We can only do this to LocalIds
+setIdNotExported id = ASSERT( isLocalId id )
+ id { idScope = LocalId NotExported }
\end{code}
%************************************************************************
%************************************************************************
\begin{code}
--- | For an explanation of global vs. local 'Var's, see "Var#globalvslocal"
-mkGlobalIdVar :: GlobalIdDetails -> Name -> Type -> IdInfo -> Var
-mkGlobalIdVar details name ty info
- = GlobalId { varName = name,
- realUnique = getKeyFastInt (nameUnique name), -- Cache the unique
- varType = ty,
- gblDetails = details,
- idInfo_ = info }
-
-mkLocalIdVar' :: Name -> Type -> LocalIdDetails -> IdInfo -> Var
-mkLocalIdVar' name ty details info
- = LocalId { varName = name,
- realUnique = getKeyFastInt (nameUnique name), -- Cache the unique
- varType = ty,
- lclDetails = details,
- idInfo_ = info }
-
--- | For an explanation of global vs. local 'Var's, see "Var#globalvslocal"
-mkLocalIdVar :: Name -> Type -> IdInfo -> Var
-mkLocalIdVar name ty info = mkLocalIdVar' name ty NotExported info
-
--- | Exported 'Var's will not be removed as dead code
-mkExportedLocalIdVar :: Name -> Type -> IdInfo -> Var
-mkExportedLocalIdVar name ty info = mkLocalIdVar' name ty Exported info
-\end{code}
-
-\begin{code}
isTyVar :: Var -> Bool
isTyVar (TyVar {}) = True
isTyVar (TcTyVar {}) = True
isTcTyVar (TcTyVar {}) = True
isTcTyVar _ = False
-isIdVar :: Var -> Bool
-isIdVar (LocalId {}) = True
-isIdVar (GlobalId {}) = True
-isIdVar _ = False
+isId :: Var -> Bool
+isId (Id {}) = True
+isId _ = False
-isLocalIdVar :: Var -> Bool
-isLocalIdVar (LocalId {}) = True
-isLocalIdVar _ = False
+isLocalId :: Var -> Bool
+isLocalId (Id { idScope = LocalId _ }) = True
+isLocalId _ = False
isCoVar :: Var -> Bool
isCoVar (v@(TyVar {})) = isCoercionVar v
-- These are the variables that we need to pay attention to when finding free
-- variables, or doing dependency analysis.
isLocalVar :: Var -> Bool
-isLocalVar (GlobalId {}) = False
-isLocalVar _ = True
+isLocalVar v = not (isGlobalId v)
+
+isGlobalId :: Var -> Bool
+isGlobalId (Id { idScope = GlobalId }) = True
+isGlobalId _ = False
-- | 'mustHaveLocalBinding' returns @True@ of 'Id's and 'TyVar's
-- that must have a binding in this module. The converse
mustHaveLocalBinding :: Var -> Bool
mustHaveLocalBinding var = isLocalVar var
-isGlobalIdVar :: Var -> Bool
-isGlobalIdVar (GlobalId {}) = True
-isGlobalIdVar _ = False
-
-- | 'isExportedIdVar' means \"don't throw this away\"
-isExportedIdVar :: Var -> Bool
-isExportedIdVar (GlobalId {}) = True
-isExportedIdVar (LocalId {lclDetails = details})
- = case details of
- Exported -> True
- _ -> False
-isExportedIdVar _ = False
-\end{code}
-
-\begin{code}
-globalIdVarDetails :: Var -> GlobalIdDetails
--- ^ Find the global 'Id' information if the 'Var' is a global 'Id', otherwise returns 'notGlobalId'
-globalIdVarDetails (GlobalId {gblDetails = details}) = details
-globalIdVarDetails _ = notGlobalId
+isExportedId :: Var -> Bool
+isExportedId (Id { idScope = GlobalId }) = True
+isExportedId (Id { idScope = LocalId Exported}) = True
+isExportedId _ = False
\end{code}
mkConApp, mkTyBind,
varToCoreExpr, varsToCoreExprs,
- isTyVar, isIdVar, cmpAltCon, cmpAlt, ltAlt,
+ isTyVar, isId, cmpAltCon, cmpAlt, ltAlt,
-- ** Simple 'Expr' access functions and predicates
bindersOf, bindersOfBinds, rhssOfBind, rhssOfAlts,
-- | Convert a binder into either a 'Var' or 'Type' 'Expr' appropriately
varToCoreExpr :: CoreBndr -> Expr b
-varToCoreExpr v | isIdVar v = Var v
+varToCoreExpr v | isId v = Var v
| otherwise = Type (mkTyVarTy v)
varsToCoreExprs :: [CoreBndr] -> [Expr b]
collectValBinders expr
= go [] expr
where
- go ids (Lam b e) | isIdVar b = go (b:ids) e
- go ids body = (reverse ids, body)
+ go ids (Lam b e) | isId b = go (b:ids) e
+ go ids body = (reverse ids, body)
\end{code}
\begin{code}
\begin{code}
-- | Will this variable exist at runtime?
isRuntimeVar :: Var -> Bool
-isRuntimeVar = isIdVar
+isRuntimeVar = isId
-- | Will this argument expression exist at runtime?
isRuntimeArg :: CoreExpr -> Bool
-- | The number of binders that bind values rather than types
valBndrCount :: [CoreBndr] -> Int
-valBndrCount = count isIdVar
+valBndrCount = count isId
-- | The number of argument expressions that are values rather than types at their top level
valArgCount :: [Arg b] -> Int
| fun `hasKey` buildIdKey = buildSize
| fun `hasKey` augmentIdKey = augmentSize
| otherwise
- = case globalIdDetails fun of
+ = case idDetails fun of
DataConWorkId dc -> conSizeN dc (valArgCount args)
FCallId _ -> sizeN opt_UF_DearOp
to work ok now.
Note [Lone variables]
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+~~~~~~~~~~~~~~~~~~~~~
The "lone-variable" case is important. I spent ages messing about
with unsatisfactory varaints, but this is nice. The idea is that if a
variable appears all alone
go (Var _) [] = True -- Just a type application of a variable
-- (f t1 t2 t3) counts as WHNF
go (Var f) args
- = case globalIdDetails f of
- RecordSelId {} -> go_sel args
- ClassOpId _ -> go_sel args
- PrimOpId op -> go_primop op args
+ = case idDetails f of
+ RecSelId {} -> go_sel args
+ ClassOpId _ -> go_sel args
+ PrimOpId op -> go_primop op args
DataConWorkId _ -> go_pap args
_ | length args < idArity f -> go_pap args
exprOkForSpeculation (Cast e _) = exprOkForSpeculation e
exprOkForSpeculation other_expr
= case collectArgs other_expr of
- (Var f, args) -> spec_ok (globalIdDetails f) args
+ (Var f, args) -> spec_ok (idDetails f) args
_ -> False
where
let vName = Var.varName v
isLocal <- isALocal vName
return $
- case globalIdVarDetails v of
+ case idDetails v of
FCallId (CCall (CCallSpec (StaticTarget nm) callconv _))
-> C.External (unpackFS nm) (showSDoc (ppr callconv)) (make_ty (varType v))
FCallId (CCall (CCallSpec DynamicTarget callconv _))
pprCoreBinder LetBind binder
| isTyVar binder = pprKindedTyVarBndr binder
| otherwise
- = vcat [sig, pprIdDetails binder, pragmas]
+ = vcat [sig, pprIdExtras binder, pragmas]
where
sig = pprTypedBinder binder
pragmas = ppIdInfo binder (idInfo binder)
\begin{code}
-pprIdDetails :: Id -> SDoc
-pprIdDetails id | isGlobalId id = ppr (globalIdDetails id)
- | isExportedId id = ptext (sLit "[Exported]")
- | otherwise = empty
+pprIdExtras :: Id -> SDoc
+pprIdExtras id = pp_scope <> ppr (idDetails id)
+ where
+ pp_scope | isGlobalId id = ptext (sLit "GblId")
+ | isExportedId id = ptext (sLit "LclIdX")
+ | otherwise = ptext (sLit "LclId")
ppIdInfo :: Id -> IdInfo -> SDoc
ppIdInfo _ info
import RtClosureInspect
import HscTypes
-import IdInfo
import Id
import Name
import Var hiding ( varName )
(t', stuff) <- liftIO $ foldTerm (nameSuspensionsAndGetInfos availNames_var) t
let (names, tys, hvals) = unzip3 stuff
(tys', skol_vars) = unzip $ map skolemiseTy tys
- let ids = [ mkGlobalId VanillaGlobal name ty vanillaIdInfo
+ let ids = [ mkVanillaGlobal name ty
| (name,ty) <- zip names tys']
new_ic = extendInteractiveContext ictxt ids (unionVarSets skol_vars)
liftIO $ extendLinkEnv (zip names hvals)
name <- newGrimName userName
let ictxt = hsc_IC hsc_env
tmp_ids = ic_tmp_ids ictxt
- id = mkGlobalId VanillaGlobal name ty vanillaIdInfo
+ id = mkVanillaGlobal name ty
new_ic = ictxt { ic_tmp_ids = id : tmp_ids }
return (hsc_env {hsc_IC = new_ic }, name)
data Sig name -- Signatures and pragmas
= -- An ordinary type signature
-- f :: Num a => a -> a
- TypeSig (Located name) -- A bog-std type signature
- (LHsType name)
+ TypeSig (Located name) (LHsType name)
+
+ -- A type signature in generated code, notably the code
+ -- generated for record selectors. We simply record
+ -- the desired Id itself, replete with its name, type
+ -- and IdDetails. Otherwise it's just like a type
+ -- signature: there should be an accompanying binding
+ | IdSig Id
-- An ordinary fixity declaration
-- infixl *** 8
- | FixSig (FixitySig name) -- Fixity declaration
+ | FixSig (FixitySig name)
-- An inline pragma
-- {#- INLINE f #-}
isFixityLSig (L _ (FixSig {})) = True
isFixityLSig _ = False
-isVanillaLSig :: LSig name -> Bool
+isVanillaLSig :: LSig name -> Bool -- User type signatures
+-- A badly-named function, but it's part of the GHCi (used
+-- by Haddock) so I don't want to change it gratuitously.
isVanillaLSig (L _(TypeSig {})) = True
isVanillaLSig _ = False
+isTypeLSig :: LSig name -> Bool -- Type signatures
+isTypeLSig (L _(TypeSig {})) = True
+isTypeLSig (L _(IdSig {})) = True
+isTypeLSig _ = False
+
isSpecLSig :: LSig name -> Bool
isSpecLSig (L _(SpecSig {})) = True
isSpecLSig _ = False
hsSigDoc :: Sig name -> SDoc
hsSigDoc (TypeSig {}) = ptext (sLit "type signature")
+hsSigDoc (IdSig {}) = ptext (sLit "id signature")
hsSigDoc (SpecSig {}) = ptext (sLit "SPECIALISE pragma")
hsSigDoc (InlineSig {}) = ptext (sLit "INLINE pragma")
hsSigDoc (SpecInstSig {}) = ptext (sLit "SPECIALISE instance pragma")
\begin{code}
eqHsSig :: Eq a => LSig a -> LSig a -> Bool
eqHsSig (L _ (FixSig (FixitySig n1 _))) (L _ (FixSig (FixitySig n2 _))) = unLoc n1 == unLoc n2
+eqHsSig (L _ (IdSig n1)) (L _ (IdSig n2)) = n1 == n2
eqHsSig (L _ (TypeSig n1 _)) (L _ (TypeSig n2 _)) = unLoc n1 == unLoc n2
eqHsSig (L _ (InlineSig n1 _)) (L _ (InlineSig n2 _)) = unLoc n1 == unLoc n2
-- For specialisations, we don't have equality over
ppr_sig :: OutputableBndr name => Sig name -> SDoc
ppr_sig (TypeSig var ty) = pprVarSig (unLoc var) ty
+ppr_sig (IdSig id) = pprVarSig id (varType id)
ppr_sig (FixSig fix_sig) = ppr fix_sig
ppr_sig (SpecSig var ty inl) = pragBrackets (pprSpec var ty inl)
ppr_sig (InlineSig var inl) = pragBrackets (ppr inl <+> ppr var)
return (ActiveAfter ab)
instance Binary StrictnessMark where
- put_ bh MarkedStrict = do
- putByte bh 0
- put_ bh MarkedUnboxed = do
- putByte bh 1
- put_ bh NotMarkedStrict = do
- putByte bh 2
+ put_ bh MarkedStrict = putByte bh 0
+ put_ bh MarkedUnboxed = putByte bh 1
+ put_ bh NotMarkedStrict = putByte bh 2
get bh = do
h <- getByte bh
case h of
_ -> do return NotMarkedStrict
instance Binary Boxity where
- put_ bh Boxed = do
- putByte bh 0
- put_ bh Unboxed = do
- putByte bh 1
+ put_ bh Boxed = putByte bh 0
+ put_ bh Unboxed = putByte bh 1
get bh = do
h <- getByte bh
case h of
_ -> do ac <- get bh
return (IfaceRec ac)
+instance Binary IfaceIdDetails where
+ put_ bh IfVanillaId = putByte bh 0
+ put_ bh (IfRecSelId b) = do { putByte bh 1; put_ bh b }
+ put_ bh IfDFunId = putByte bh 2
+ get bh = do
+ h <- getByte bh
+ case h of
+ 0 -> return IfVanillaId
+ 1 -> do a <- get bh
+ return (IfRecSelId a)
+ _ -> return IfDFunId
+
instance Binary IfaceIdInfo where
put_ bh NoInfo = putByte bh 0
put_ bh (HasInfo i) = do
-- when de-serialising.
instance Binary IfaceDecl where
- put_ bh (IfaceId name ty idinfo) = do
+ put_ bh (IfaceId name ty details idinfo) = do
putByte bh 0
put_ bh (occNameFS name)
put_ bh ty
+ put_ bh details
put_ bh idinfo
put_ _ (IfaceForeign _ _) =
error "Binary.put_(IfaceDecl): IfaceForeign"
get bh = do
h <- getByte bh
case h of
- 0 -> do name <- get bh
- ty <- get bh
- idinfo <- get bh
+ 0 -> do name <- get bh
+ ty <- get bh
+ details <- get bh
+ idinfo <- get bh
occ <- return $! mkOccNameFS varName name
- return (IfaceId occ ty idinfo)
+ return (IfaceId occ ty details idinfo)
1 -> error "Binary.get(TyClDecl): ForeignType"
2 -> do
a1 <- get bh
return (IfNewTyCon aa)
instance Binary IfaceConDecl where
- put_ bh (IfCon a1 a2 a3 a4 a5 a6 a7 a8 a9) = do
+ put_ bh (IfCon a1 a2 a3 a4 a5 a6 a7 a8 a9 a10) = do
put_ bh a1
put_ bh a2
put_ bh a3
put_ bh a7
put_ bh a8
put_ bh a9
+ put_ bh a10
get bh = do a1 <- get bh
a2 <- get bh
a3 <- get bh
a7 <- get bh
a8 <- get bh
a9 <- get bh
- return (IfCon a1 a2 a3 a4 a5 a6 a7 a8 a9)
+ a10 <- get bh
+ return (IfCon a1 a2 a3 a4 a5 a6 a7 a8 a9 a10)
instance Binary IfaceClassOp where
put_ bh (IfaceClassOp n def ty) = do
; tycon <- fixM (\ tycon_rec -> do
{ parent <- mkParentInfo mb_family tc_name tvs tycon_rec
; let { tycon = mkAlgTyCon tc_name kind tvs stupid_theta rhs
- fields parent is_rec want_generics gadt_syn
- ; kind = mkArrowKinds (map tyVarKind tvs) liftedTypeKind
- ; fields = mkTyConSelIds tycon rhs
+ parent is_rec want_generics gadt_syn
+ ; kind = mkArrowKinds (map tyVarKind tvs) liftedTypeKind
}
; return tycon
})
arg_tyvars = tyVarsOfTypes arg_tys
in_arg_tys pred = not $ isEmptyVarSet $
tyVarsOfPred pred `intersectVarSet` arg_tyvars
-
-------------------------------------------------------
-mkTyConSelIds :: TyCon -> AlgTyConRhs -> [Id]
-mkTyConSelIds tycon rhs
- = [ mkRecordSelId tycon fld
- | fld <- nub (concatMap dataConFieldLabels (visibleDataCons rhs)) ]
- -- We'll check later that fields with the same name
- -- from different constructors have the same type.
\end{code}
let { rec_tycon = classTyCon rec_clas
; op_tys = [ty | (_,_,ty) <- sig_stuff]
+ ; op_names = [op | (op,_,_) <- sig_stuff]
; op_items = [ (mkDictSelId no_unf op_name rec_clas, dm_info)
| (op_name, dm_info, _) <- sig_stuff ] }
-- Build the selector id and default method id
- ; dict_con <- buildDataCon datacon_name
- False -- Not declared infix
- (map (const NotMarkedStrict) op_tys)
- [{- No labelled fields -}]
- tvs [{- no existentials -}]
- [{- No GADT equalities -}] sc_theta
- op_tys
- (mkTyConApp rec_tycon (mkTyVarTys tvs))
- rec_tycon
-
; let n_value_preds = count (not . isEqPred) sc_theta
all_value_preds = n_value_preds == length sc_theta
-- We only make selectors for the *value* superclasses,
-- i.e. exactly one operation or superclass taken together
-- See note [Class newtypes and equality predicates]
+ -- We play a bit fast and loose by treating the superclasses
+ -- as ordinary arguments. That means that in the case of
+ -- class C a => D a
+ -- we don't get a newtype with no arguments!
+ args = sc_sel_names ++ op_names
+ arg_tys = map mkPredTy sc_theta ++ op_tys
+
+ ; dict_con <- buildDataCon datacon_name
+ False -- Not declared infix
+ (map (const NotMarkedStrict) args)
+ [{- No fields -}]
+ tvs [{- no existentials -}]
+ [{- No GADT equalities -}] [{- No theta -}]
+ arg_tys
+ (mkTyConApp rec_tycon (mkTyVarTys tvs))
+ rec_tycon
+
; rhs <- if use_newtype
then mkNewTyConRhs tycon_name rec_tycon dict_con
else return (mkDataTyConRhs [dict_con])
IfaceDecl(..), IfaceClassOp(..), IfaceConDecl(..), IfaceConDecls(..),
IfaceExpr(..), IfaceAlt, IfaceNote(..), IfaceLetBndr(..),
- IfaceBinding(..), IfaceConAlt(..), IfaceIdInfo(..),
+ IfaceBinding(..), IfaceConAlt(..), IfaceIdInfo(..), IfaceIdDetails(..),
IfaceInfoItem(..), IfaceRule(..), IfaceAnnotation(..), IfaceAnnTarget,
IfaceInst(..), IfaceFamInst(..),
\begin{code}
data IfaceDecl
- = IfaceId { ifName :: OccName,
- ifType :: IfaceType,
- ifIdInfo :: IfaceIdInfo }
+ = IfaceId { ifName :: OccName,
+ ifType :: IfaceType,
+ ifIdDetails :: IfaceIdDetails,
+ ifIdInfo :: IfaceIdInfo }
| IfaceData { ifName :: OccName, -- Type constructor
ifTyVars :: [IfaceTvBndr], -- Type variables
data IfaceConDecl
= IfCon {
ifConOcc :: OccName, -- Constructor name
+ ifConWrapper :: Bool, -- True <=> has a wrapper
ifConInfix :: Bool, -- True <=> declared infix
ifConUnivTvs :: [IfaceTvBndr], -- Universal tyvars
ifConExTvs :: [IfaceTvBndr], -- Existential tyvars
type IfaceAnnTarget = AnnTarget OccName
+-- We only serialise the IdDetails of top-level Ids, and even then
+-- we only need a very limited selection. Notably, none of the
+-- implicit ones are needed here, becuase they are not put it
+-- interface files
+
+data IfaceIdDetails
+ = IfVanillaId
+ | IfRecSelId Bool
+ | IfDFunId
+
data IfaceIdInfo
= NoInfo -- When writing interface file without -O
| HasInfo [IfaceInfoItem] -- Has info, and here it is
-- Newtype
ifaceDeclSubBndrs (IfaceData {ifName = tc_occ,
ifCons = IfNewTyCon (
- IfCon { ifConOcc = con_occ,
- ifConFields = fields
- }),
+ IfCon { ifConOcc = con_occ }),
ifFamInst = famInst})
- = -- fields (names of selectors)
- fields ++
- -- implicit coerion and (possibly) family instance coercion
+ = -- implicit coerion and (possibly) family instance coercion
(mkNewTyCoOcc tc_occ) : (famInstCo famInst tc_occ) ++
- -- data constructor and worker (newtypes don't have a wrapper)
+ -- data constructor and worker (newtypes don't have a wrapper)
[con_occ, mkDataConWorkerOcc con_occ]
ifaceDeclSubBndrs (IfaceData {ifName = tc_occ,
ifCons = IfDataTyCon cons,
ifFamInst = famInst})
- = -- fields (names of selectors)
- nub (concatMap ifConFields cons) -- Eliminate duplicate fields
- -- (possibly) family instance coercion;
- -- there is no implicit coercion for non-newtypes
- ++ famInstCo famInst tc_occ
- -- for each data constructor in order,
- -- data constructor, worker, and (possibly) wrapper
+ = -- (possibly) family instance coercion;
+ -- there is no implicit coercion for non-newtypes
+ famInstCo famInst tc_occ
+ -- for each data constructor in order,
+ -- data constructor, worker, and (possibly) wrapper
++ concatMap dc_occs cons
where
dc_occs con_decl
wrap_occ = mkDataConWrapperOcc con_occ -- Id namespace
work_occ = mkDataConWorkerOcc con_occ -- Id namespace
strs = ifConStricts con_decl
- has_wrapper = any isMarkedStrict strs -- See MkId.mkDataConIds (sigh)
- || not (null . ifConEqSpec $ con_decl)
- || isJust famInst
- -- ToDo: may miss strictness in existential dicts
+ has_wrapper = ifConWrapper con_decl -- This is the reason for
+ -- having the ifConWrapper field!
ifaceDeclSubBndrs (IfaceClass {ifCtxt = sc_ctxt, ifName = cls_occ,
ifSigs = sigs, ifATs = ats })
ppr = pprIfaceDecl
pprIfaceDecl :: IfaceDecl -> SDoc
-pprIfaceDecl (IfaceId {ifName = var, ifType = ty, ifIdInfo = info})
+pprIfaceDecl (IfaceId {ifName = var, ifType = ty,
+ ifIdDetails = details, ifIdInfo = info})
= sep [ ppr var <+> dcolon <+> ppr ty,
+ nest 2 (ppr details),
nest 2 (ppr info) ]
pprIfaceDecl (IfaceForeign {ifName = tycon})
pprIfaceConDecl :: OccName -> IfaceConDecl -> SDoc
pprIfaceConDecl tc
- (IfCon { ifConOcc = name, ifConInfix = is_infix,
+ (IfCon { ifConOcc = name, ifConInfix = is_infix, ifConWrapper = has_wrap,
ifConUnivTvs = univ_tvs, ifConExTvs = ex_tvs,
ifConEqSpec = eq_spec, ifConCtxt = ctxt, ifConArgTys = arg_tys,
ifConStricts = strs, ifConFields = fields })
= sep [main_payload,
if is_infix then ptext (sLit "Infix") else empty,
+ if has_wrap then ptext (sLit "HasWrapper") else empty,
if null strs then empty
else nest 4 (ptext (sLit "Stricts:") <+> hsep (map ppr strs)),
if null fields then empty
-- IfaceTupleAlt is handled by the case-alternative printer
------------------
+instance Outputable IfaceIdDetails where
+ ppr IfVanillaId = empty
+ ppr (IfRecSelId b) = ptext (sLit "RecSel")
+ <> if b then ptext (sLit "<naughty>") else empty
+ ppr IfDFunId = ptext (sLit "DFunId")
+
instance Outputable IfaceIdInfo where
ppr NoInfo = empty
ppr (HasInfo is) = ptext (sLit "{-") <+> fsep (map ppr is) <+> ptext (sLit "-}")
-- fingerprinting the instance, so DFuns are not dependencies.
freeNamesIfDecl :: IfaceDecl -> NameSet
-freeNamesIfDecl (IfaceId _s t i) =
+freeNamesIfDecl (IfaceId _s t _d i) =
freeNamesIfType t &&&
freeNamesIfIdInfo i
freeNamesIfDecl IfaceForeign{} =
-- | An 'IfM' function to load the home interface for a wired-in thing,
-- so that we're sure that we see its instance declarations and rules
--- See Note [Loading instances]
+-- See Note [Loading instances for wired-in things] in TcIface
loadWiredInHomeIface :: Name -> IfM lcl ()
loadWiredInHomeIface name
= ASSERT( isWiredInName name )
Succeeded iface -> return iface }
\end{code}
-Note [Loading instances]
-~~~~~~~~~~~~~~~~~~~~~~~~
-We need to make sure that we have at least *read* the interface files
-for any module with an instance decl or RULE that we might want.
-
-* If the instance decl is an orphan, we have a whole separate mechanism
- (loadOprhanModules)
-
-* If the instance decl not an orphan, then the act of looking at the
- TyCon or Class will force in the defining module for the
- TyCon/Class, and hence the instance decl
-
-* BUT, if the TyCon is a wired-in TyCon, we don't really need its interface;
- but we must make sure we read its interface in case it has instances or
- rules. That is what LoadIface.loadWiredInHomeInterface does. It's called
- from TcIface.{tcImportDecl, checkWiredInTyCon, ifCHeckWiredInThing}
-
-All of this is done by the type checker. The renamer plays no role.
-(It used to, but no longer.)
-
-
%*********************************************************
%* *
-- Reason: Iface stuff uses OccNames, and the conversion here does
-- not do tidying on the way
tyThingToIfaceDecl (AnId id)
- = IfaceId { ifName = getOccName id,
- ifType = toIfaceType (idType id),
- ifIdInfo = info }
+ = IfaceId { ifName = getOccName id,
+ ifType = toIfaceType (idType id),
+ ifIdDetails = toIfaceIdDetails (idDetails id),
+ ifIdInfo = info }
where
info = case toIfaceIdInfo (idInfo id) of
[] -> NoInfo
ifaceConDecl data_con
= IfCon { ifConOcc = getOccName (dataConName data_con),
ifConInfix = dataConIsInfix data_con,
+ ifConWrapper = isJust (dataConWrapId_maybe data_con),
ifConUnivTvs = toIfaceTvBndrs (dataConUnivTyVars data_con),
ifConExTvs = toIfaceTvBndrs (dataConExTyVars data_con),
ifConEqSpec = to_eq_spec (dataConEqSpec data_con),
| otherwise = HasInfo [HsInline inline_prag]
--------------------------
+toIfaceIdDetails :: IdDetails -> IfaceIdDetails
+toIfaceIdDetails VanillaId = IfVanillaId
+toIfaceIdDetails DFunId = IfVanillaId
+toIfaceIdDetails (RecSelId { sel_naughty = n }) = IfRecSelId n
+toIfaceIdDetails other = pprTrace "toIfaceIdDetails" (ppr other)
+ IfVanillaId -- Unexpected
+
toIfaceIdInfo :: IdInfo -> [IfaceInfoItem]
toIfaceIdInfo id_info
= catMaybes [arity_hsinfo, caf_hsinfo, strict_hsinfo,
import IfaceEnv
import BuildTyCl
import TcRnMonad
+import TcType ( tcSplitSigmaTy )
import Type
import TypeRep
import HscTypes
-- Entry point for *source-code* uses of importDecl
tcImportDecl name
| Just thing <- wiredInNameTyThing_maybe name
- = do { initIfaceTcRn (loadWiredInHomeIface name)
- -- See Note [Loading instances] in LoadIface
+ = do { when (needWiredInHomeIface thing)
+ (initIfaceTcRn (loadWiredInHomeIface name))
+ -- See Note [Loading instances for wired-in things]
; return thing }
| otherwise
= do { traceIf (text "tcImportDecl" <+> ppr name)
Succeeded thing -> return thing
Failed err -> failWithTc err }
-checkWiredInTyCon :: TyCon -> TcM ()
--- Ensure that the home module of the TyCon (and hence its instances)
--- are loaded. See See Note [Loading instances] in LoadIface
--- It might not be a wired-in tycon (see the calls in TcUnify),
--- in which case this is a no-op.
-checkWiredInTyCon tc
- | not (isWiredInName tc_name)
- = return ()
- | otherwise
- = do { mod <- getModule
- ; ASSERT( isExternalName tc_name )
- unless (mod == nameModule tc_name)
- (initIfaceTcRn (loadWiredInHomeIface tc_name))
- -- Don't look for (non-existent) Float.hi when
- -- compiling Float.lhs, which mentions Float of course
- -- A bit yukky to call initIfaceTcRn here
- }
- where
- tc_name = tyConName tc
-
importDecl :: Name -> IfM lcl (MaybeErr Message TyThing)
-- Get the TyThing for this Name from an interface file
-- It's not a wired-in thing -- the caller caught that
%************************************************************************
%* *
+ Checks for wired-in things
+%* *
+%************************************************************************
+
+Note [Loading instances for wired-in things]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+We need to make sure that we have at least *read* the interface files
+for any module with an instance decl or RULE that we might want.
+
+* If the instance decl is an orphan, we have a whole separate mechanism
+ (loadOprhanModules)
+
+* If the instance decl not an orphan, then the act of looking at the
+ TyCon or Class will force in the defining module for the
+ TyCon/Class, and hence the instance decl
+
+* BUT, if the TyCon is a wired-in TyCon, we don't really need its interface;
+ but we must make sure we read its interface in case it has instances or
+ rules. That is what LoadIface.loadWiredInHomeInterface does. It's called
+ from TcIface.{tcImportDecl, checkWiredInTyCon, ifCheckWiredInThing}
+
+* HOWEVER, only do this for TyCons. There are no wired-in Classes. There
+ are some wired-in Ids, but we don't want to load their interfaces. For
+ example, Control.Exception.Base.recSelError is wired in, but that module
+ is compiled late in the base library, and we don't want to force it to
+ load before it's been compiled!
+
+All of this is done by the type checker. The renamer plays no role.
+(It used to, but no longer.)
+
+
+\begin{code}
+checkWiredInTyCon :: TyCon -> TcM ()
+-- Ensure that the home module of the TyCon (and hence its instances)
+-- are loaded. See Note [Loading instances for wired-in things]
+-- It might not be a wired-in tycon (see the calls in TcUnify),
+-- in which case this is a no-op.
+checkWiredInTyCon tc
+ | not (isWiredInName tc_name)
+ = return ()
+ | otherwise
+ = do { mod <- getModule
+ ; ASSERT( isExternalName tc_name )
+ when (mod /= nameModule tc_name)
+ (initIfaceTcRn (loadWiredInHomeIface tc_name))
+ -- Don't look for (non-existent) Float.hi when
+ -- compiling Float.lhs, which mentions Float of course
+ -- A bit yukky to call initIfaceTcRn here
+ }
+ where
+ tc_name = tyConName tc
+
+ifCheckWiredInThing :: TyThing -> IfL ()
+-- Even though we are in an interface file, we want to make
+-- sure the instances of a wired-in thing are loaded (imagine f :: Double -> Double)
+-- Ditto want to ensure that RULES are loaded too
+-- See Note [Loading instances for wired-in things]
+ifCheckWiredInThing thing
+ = do { mod <- getIfModule
+ -- Check whether we are typechecking the interface for this
+ -- very module. E.g when compiling the base library in --make mode
+ -- we may typecheck GHC.Base.hi. At that point, GHC.Base is not in
+ -- the HPT, so without the test we'll demand-load it into the PIT!
+ -- C.f. the same test in checkWiredInTyCon above
+ ; let name = getName thing
+ ; ASSERT2( isExternalName name, ppr name )
+ when (needWiredInHomeIface thing && mod /= nameModule name)
+ (loadWiredInHomeIface name) }
+
+needWiredInHomeIface :: TyThing -> Bool
+-- Only for TyCons; see Note [Loading instances for wired-in things]
+needWiredInHomeIface (ATyCon {}) = True
+needWiredInHomeIface _ = False
+\end{code}
+
+%************************************************************************
+%* *
Type-checking a complete interface
%* *
%************************************************************************
-> IfaceDecl
-> IfL TyThing
-tcIfaceDecl ignore_prags (IfaceId {ifName = occ_name, ifType = iface_type, ifIdInfo = info})
+tcIfaceDecl ignore_prags (IfaceId {ifName = occ_name, ifType = iface_type,
+ ifIdDetails = details, ifIdInfo = info})
= do { name <- lookupIfaceTop occ_name
; ty <- tcIfaceType iface_type
+ ; details <- tcIdDetails ty details
; info <- tcIdInfo ignore_prags name ty info
- ; return (AnId (mkVanillaGlobalWithInfo name ty info)) }
+ ; return (AnId (mkGlobalId details name ty info)) }
tcIfaceDecl _ (IfaceData {ifName = occ_name,
ifTyVars = tv_bndrs,
%************************************************************************
\begin{code}
+tcIdDetails :: Type -> IfaceIdDetails -> IfL IdDetails
+tcIdDetails _ IfVanillaId = return VanillaId
+tcIdDetails _ IfDFunId = return DFunId
+tcIdDetails ty (IfRecSelId naughty)
+ = return (RecSelId { sel_tycon = tc, sel_naughty = naughty })
+ where
+ (_, _, tau) = tcSplitSigmaTy ty
+ tc = tyConAppTyCon (funArgTy tau)
+ -- A bit fragile. Relies on the selector type looking like
+ -- forall abc. (stupid-context) => T a b c -> blah
+
tcIdInfo :: Bool -> Name -> Type -> IfaceIdInfo -> IfL IdInfo
tcIdInfo ignore_prags name ty info
| ignore_prags = return vanillaIdInfo
tcIfaceGlobal name
| Just thing <- wiredInNameTyThing_maybe name
-- Wired-in things include TyCons, DataCons, and Ids
- = do { ifCheckWiredInThing name; return thing }
+ = do { ifCheckWiredInThing thing; return thing }
| otherwise
= do { env <- getGblEnv
; case if_rec_types env of { -- Note [Tying the knot]
-- Because if M.hs also has M.hs-boot, M.T will *already be* in the HPT, but in its
-- emasculated form (e.g. lacking data constructors).
-ifCheckWiredInThing :: Name -> IfL ()
--- Even though we are in an interface file, we want to make
--- sure the instances of a wired-in thing are loaded (imagine f :: Double -> Double)
--- Ditto want to ensure that RULES are loaded too
--- See Note [Loading instances] in LoadIface
-ifCheckWiredInThing name
- = do { mod <- getIfModule
- -- Check whether we are typechecking the interface for this
- -- very module. E.g when compiling the base library in --make mode
- -- we may typecheck GHC.Base.hi. At that point, GHC.Base is not in
- -- the HPT, so without the test we'll demand-load it into the PIT!
- -- C.f. the same test in checkWiredInTyCon above
- ; ASSERT2( isExternalName name, ppr name )
- unless (mod == nameModule name)
- (loadWiredInHomeIface name) }
-
tcIfaceTyCon :: IfaceTyCon -> IfL TyCon
tcIfaceTyCon IfaceIntTc = tcWiredInTyCon intTyCon
tcIfaceTyCon IfaceBoolTc = tcWiredInTyCon boolTyCon
-- sure the instances and RULES of this tycon are loaded
-- Imagine: f :: Double -> Double
tcWiredInTyCon :: TyCon -> IfL TyCon
-tcWiredInTyCon tc = do { ifCheckWiredInThing (tyConName tc)
+tcWiredInTyCon tc = do { ifCheckWiredInThing (ATyCon tc)
; return tc }
tcIfaceClass :: Name -> IfL Class
implicitTyThings :: TyThing -> [TyThing]
-- For data and newtype declarations:
-implicitTyThings (ATyCon tc) =
- -- fields (names of selectors)
- map AnId (tyConSelIds tc) ++
- -- (possibly) implicit coercion and family coercion
- -- depending on whether it's a newtype or a family instance or both
+implicitTyThings (ATyCon tc)
+ = -- fields (names of selectors)
+ -- (possibly) implicit coercion and family coercion
+ -- depending on whether it's a newtype or a family instance or both
implicitCoTyCon tc ++
- -- for each data constructor in order,
- -- the contructor, worker, and (possibly) wrapper
+ -- for each data constructor in order,
+ -- the contructor, worker, and (possibly) wrapper
concatMap (extras_plus . ADataCon) (tyConDataCons tc)
implicitTyThings (AClass cl)
e_fs = fsLit "e"
e_name = mkInternalName (getUnique e_fs) (mkTyVarOccFS e_fs) span
e_tyvar = mkTcTyVar e_name liftedTypeKind (SkolemTv RuntimeUnkSkol)
- exn_id = Id.mkGlobalId VanillaGlobal exn_name (mkTyVarTy e_tyvar)
- vanillaIdInfo
+ exn_id = Id.mkVanillaGlobal exn_name (mkTyVarTy e_tyvar)
new_tyvars = unitVarSet e_tyvar
ictxt0 = hsc_IC hsc_env
-- _result in scope at any time.
let result_name = mkInternalName (getUnique result_fs)
(mkVarOccFS result_fs) span
- result_id = Id.mkGlobalId VanillaGlobal result_name result_ty
- vanillaIdInfo
+ result_id = Id.mkVanillaGlobal result_name result_ty
-- for each Id we're about to bind in the local envt:
-- - skolemise the type variables in its type, so they can't
loc = nameSrcSpan (idName id)
name = mkInternalName uniq occ loc
ty = idType id
- new_id = Id.mkGlobalId VanillaGlobal name ty (idInfo id)
+ new_id = Id.mkVanillaGlobalWithInfo name ty (idInfo id)
return new_id
rttiEnvironment :: HscEnv -> IO HscEnv
\section{Tidying up Core}
\begin{code}
-module TidyPgm( mkBootModDetailsDs, mkBootModDetailsTc, tidyProgram ) where
+module TidyPgm( mkBootModDetailsDs, mkBootModDetailsTc,
+ tidyProgram, globaliseAndTidyId ) where
#include "HsVersions.h"
import PprCore
import CoreLint
import CoreUtils
+import Class ( classSelIds )
import VarEnv
import VarSet
import Var
import Id
-import Class
import IdInfo
import InstEnv
import NewDemand
= do { let dflags = hsc_dflags hsc_env
; showPass dflags "Tidy [hoot] type env"
- ; let { insts' = tidyInstances tidyExternalId insts
+ ; let { insts' = tidyInstances globaliseAndTidyId insts
; dfun_ids = map instanceDFunId insts'
; type_env1 = tidyBootTypeEnv (availsToNameSet exports) type_env
; type_env' = extendTypeEnvWithIds type_env1 dfun_ids
-- because we don't tidy the OccNames, and if we don't remove
-- the non-exported ones we'll get many things with the
-- same name in the interface file, giving chaos.
- final_ids = [ tidyExternalId id
+ final_ids = [ globaliseAndTidyId id
| id <- typeEnvIds type_env
, isLocalId id
, keep_it id ]
keep_it id = isExportedId id || idName id `elemNameSet` exports
-tidyExternalId :: Id -> Id
+
+globaliseAndTidyId :: Id -> Id
-- Takes an LocalId with an External Name,
--- makes it into a GlobalId with VanillaIdInfo, and tidies its type
--- (NB: vanillaIdInfo makes a conservative assumption about Caf-hood.)
-tidyExternalId id
- = ASSERT2( isLocalId id && isExternalName (idName id), ppr id )
- mkVanillaGlobal (idName id) (tidyTopType (idType id))
+-- makes it into a GlobalId
+-- * unchanged Name (might be Internal or External)
+-- * unchanged details
+-- * VanillaIdInfo (makes a conservative assumption about Caf-hood)
+globaliseAndTidyId id
+ = Id.setIdType (globaliseId id) tidy_type
+ where
+ tidy_type = tidyTopType (idType id)
\end{code}
\begin{code}
getImplicitBinds :: TypeEnv -> [CoreBind]
getImplicitBinds type_env
- = map get_defn (concatMap implicit_con_ids (typeEnvTyCons type_env)
- ++ concatMap other_implicit_ids (typeEnvElts type_env))
- -- Put the constructor wrappers first, because
- -- other implicit bindings (notably the fromT functions arising
- -- from generics) use the constructor wrappers. At least that's
- -- what External Core likes
+ = map get_defn (concatMap implicit_ids (typeEnvElts type_env))
where
- implicit_con_ids tc = mapCatMaybes dataConWrapId_maybe (tyConDataCons tc)
-
- other_implicit_ids (ATyCon tc) = filter (not . isNaughtyRecordSelector) (tyConSelIds tc)
- -- The "naughty" ones are not real functions at all
- -- They are there just so we can get decent error messages
- -- See Note [Naughty record selectors] in MkId.lhs
- other_implicit_ids (AClass cl) = classSelIds cl
- other_implicit_ids _other = []
+ implicit_ids (ATyCon tc) = mapCatMaybes dataConWrapId_maybe (tyConDataCons tc)
+ implicit_ids (AClass cls) = classSelIds cls
+ implicit_ids _ = []
get_defn :: Id -> CoreBind
get_defn id = NonRec id (unfoldingTemplate (idUnfolding id))
= (bndr', rhs')
where
bndr' = mkGlobalId details name' ty' idinfo'
- -- Preserve the GlobalIdDetails of existing global-ids
- details = case globalIdDetails bndr of
- NotGlobalId -> VanillaGlobal
- old_details -> old_details
+ details = idDetails bndr -- Preserve the IdDetails
ty' = tidyTopType (idType bndr)
rhs' = tidyExpr rhs_tidy_env rhs
idinfo = idInfo bndr
tyvars
[] -- No stupid theta
(DataTyCon cons is_enum)
- [] -- No record selectors
NoParentTyCon
is_rec
True -- All the wired-in tycons have generics
renameSig :: Maybe NameSet -> Sig RdrName -> RnM (Sig Name)
-- FixitySig is renamed elsewhere.
+renameSig _ (IdSig x)
+ = return (IdSig x) -- Actually this never occurs
renameSig mb_names sig@(TypeSig v ty)
= do { new_v <- lookupSigOccRn mb_names sig v
; new_ty <- rnHsSigType (quotes (ppr v)) ty
addBinder :: CSEnv -> Id -> (CSEnv, Id)
addBinder (CS cs in_scope sub) v
| not (v `elemInScopeSet` in_scope) = (CS cs (extendInScopeSet in_scope v) sub, v)
- | isIdVar v = (CS cs (extendInScopeSet in_scope v') (extendVarEnv sub v v'), v')
+ | isId v = (CS cs (extendInScopeSet in_scope v') (extendVarEnv sub v v'), v')
| otherwise = WARN( True, ppr v )
(CS emptyUFM in_scope sub, v)
-- This last case is the unusual situation where we have shadowing of
noFloatIntoRhs rhs = exprIsHNF (deAnnotate' rhs) -- We'd just float right back out again...
is_one_shot :: Var -> Bool
-is_one_shot b = isIdVar b && isOneShotBndr b
+is_one_shot b = isId b && isOneShotBndr b
\end{code}
new_rhss <- mapM (lvlExpr ctxt_lvl new_env) rhss
return (Rec ([TB b dest_lvl | b <- new_bndrs] `zip` new_rhss), new_env)
- | isSingleton pairs && count isIdVar abs_vars > 1
+ | isSingleton pairs && count isId abs_vars > 1
= do -- Special case for self recursion where there are
-- several variables carried around: build a local loop:
-- poly_f = \abs_vars. \lam_vars . letrec f = \lam_vars. rhs in f lam_vars
[] bndrs
where
go old_lvl bumped_major rev_lvld_bndrs (bndr:bndrs)
- | isIdVar bndr && -- Go to the next major level if this is a value binder,
+ | isId bndr && -- Go to the next major level if this is a value binder,
not bumped_major && -- and we havn't already gone to the next level (one jump per group)
not (isOneShotLambda bndr) -- and it isn't a one-shot lambda
= go new_lvl True (TB bndr new_lvl : rev_lvld_bndrs) bndrs
-- We may only want to do this if there are sufficiently few free
-- variables. We certainly only want to do it for values, and not for
-- constructors. So the simple thing is just to look for lambdas
-isFunction (_, AnnLam b e) | isIdVar b = True
+isFunction (_, AnnLam b e) | isId b = True
| otherwise = isFunction e
isFunction (_, AnnNote _ e) = isFunction e
isFunction _ = False
Nothing -> [in_var])
max_out out_var lvl
- | isIdVar out_var = case lookupVarEnv lvl_env out_var of
+ | isId out_var = case lookupVarEnv lvl_env out_var of
Just lvl' -> maxLvl lvl' lvl
Nothing -> lvl
- | otherwise = lvl -- Ignore tyvars in *maxIdLevel*
+ | otherwise = lvl -- Ignore tyvars in *maxIdLevel*
lookupVar :: LevelEnv -> Id -> LevelledExpr
lookupVar (_, _, _, id_env) v = case lookupVarEnv id_env v of
-- We are going to lambda-abstract, so nuke any IdInfo,
-- and add the tyvars of the Id (if necessary)
- zap v | isIdVar v = WARN( workerExists (idWorkerInfo v) ||
+ zap v | isId v = WARN( workerExists (idWorkerInfo v) ||
not (isEmptySpecInfo (idSpecialisation v)),
text "absVarsOf: discarding info on" <+> ppr v )
setIdInfo v vanillaIdInfo
-- we must look in x's type
-- And similarly if x is a coercion variable.
absVarsOf id_env v
- | isIdVar v = [av2 | av1 <- lookup_avs v
+ | isId v = [av2 | av1 <- lookup_avs v
, av2 <- add_tyvars av1]
| isCoVar v = add_tyvars v
| otherwise = [v]
cloneVar TopLevel env v _ _
= return (env, v) -- Don't clone top level things
cloneVar NotTopLevel env@(_,_,subst,_) v ctxt_lvl dest_lvl
- = ASSERT( isIdVar v ) do
+ = ASSERT( isId v ) do
us <- getUniqueSupplyM
let
(subst', v1) = cloneIdBndr subst us v
cloneRecVars TopLevel env vs _ _
= return (env, vs) -- Don't clone top level things
cloneRecVars NotTopLevel env@(_,_,subst,_) vs ctxt_lvl dest_lvl
- = ASSERT( all isIdVar vs ) do
+ = ASSERT( all isId vs ) do
us <- getUniqueSupplyM
let
(subst', vs1) = cloneRecIdBndrs subst us vs
import FamInstEnv
import Id
import DataCon
-import TyCon ( tyConSelIds, tyConDataCons )
+import TyCon ( tyConDataCons )
import Class ( classSelIds )
import BasicTypes ( CompilerPhase, isActive )
import VarSet
-- two regardless.
res_ty = exprType (mkApps (Var f) args)
- app = case globalIdDetails f of
+ app = case idDetails f of
DataConWorkId dc | saturated -> StgConApp dc args'
PrimOpId op -> ASSERT( saturated )
StgOpApp (StgPrimOp op) args' res_ty
-- The insight is, of course, that a demand on y is a demand on the
-- scrutinee, so we need to `both` it with the scrut demand
- alt_dmd = Eval (Prod [idNewDemandInfo b | b <- bndrs', isIdVar b])
+ alt_dmd = Eval (Prod [idNewDemandInfo b | b <- bndrs', isId b])
scrut_dmd = alt_dmd `both`
idNewDemandInfo case_bndr'
annotateLamIdBndr dmd_ty@(DmdType fv ds res) id
-- For lambdas we add the demand to the argument demands
-- Only called for Ids
- = ASSERT( isIdVar id )
+ = ASSERT( isId id )
(DmdType fv' (hacked_dmd:ds) res, setIdNewDemandInfo id hacked_dmd)
where
(fv', dmd) = removeFV fv id res
-- which is very annoying.
get_one_shots :: Expr Var -> [Bool]
get_one_shots (Lam b e)
- | isIdVar b = isOneShotLambda b : get_one_shots e
+ | isId b = isOneShotLambda b : get_one_shots e
| otherwise = get_one_shots e
get_one_shots (Note _ e) = get_one_shots e
get_one_shots _ = noOneShotInfo
import Type
import Coercion ( mkSymCoercion, splitNewTypeRepCo_maybe )
import BasicTypes ( Boxity(..) )
-import Var ( Var, isIdVar )
+import Var ( Var, isId )
import UniqSupply
import Unique
import Util ( zipWithEqual )
-- Don't do CPR if the worker doesn't have any value arguments
-- Then the worker is just a constant, so we don't want to unbox it.
; (wrap_fn_cpr, work_fn_cpr, _cpr_res_ty)
- <- if any isIdVar work_args then
+ <- if any isId work_args then
mkWWcpr res_ty res_info
else
return (id, id, res_ty)
; let (work_lam_args, work_call_args) = mkWorkerArgs work_args res_ty
- ; return ([idNewDemandInfo v | v <- work_call_args, isIdVar v],
+ ; return ([idNewDemandInfo v | v <- work_call_args, isId v],
Note InlineMe . wrap_fn_args . wrap_fn_cpr . wrap_fn_str . applyToVars work_call_args . Var,
mkLams work_lam_args. work_fn_str . work_fn_cpr . work_fn_args) }
-- We use an INLINE unconditionally, even if the wrapper turns out to be
-> ([Var], -- Lambda bound args
[Var]) -- Args at call site
mkWorkerArgs args res_ty
- | any isIdVar args || not (isUnLiftedType res_ty)
+ | any isId args || not (isUnLiftedType res_ty)
= (args, args)
| otherwise
= (args ++ [voidArgId], args ++ [realWorldPrimId])
-- signatures in it. The renamer checked all this
tcHsBootSigs (ValBindsOut binds sigs)
= do { checkTc (null binds) badBootDeclErr
- ; mapM (addLocM tc_boot_sig) (filter isVanillaLSig sigs) }
+ ; mapM (addLocM tc_boot_sig) (filter isTypeLSig sigs) }
where
tc_boot_sig (TypeSig (L _ name) ty)
= do { sigma_ty <- tcHsSigType (FunSigCtxt name) ty
tcValBinds top_lvl (ValBindsOut binds sigs) thing_inside
= do { -- Typecheck the signature
; let { prag_fn = mkPragFun sigs
- ; ty_sigs = filter isVanillaLSig sigs
+ ; ty_sigs = filter isTypeLSig sigs
; sig_fn = mkTcSigFun ty_sigs }
; poly_ids <- checkNoErrs (mapAndRecoverM tcTySig ty_sigs)
tcPrag poly_id (SpecSig _ hs_ty inl) = tcSpecPrag poly_id hs_ty inl
tcPrag poly_id (SpecInstSig hs_ty) = tcSpecPrag poly_id hs_ty defaultInlineSpec
tcPrag _ (InlineSig _ inl) = return (InlinePrag inl)
-tcPrag _ (FixSig {}) = panic "tcPrag FixSig"
-tcPrag _ (TypeSig {}) = panic "tcPrag TypeSig"
+tcPrag _ sig = pprPanic "tcPrag" (ppr sig)
tcSpecPrag :: TcId -> LHsType Name -> InlineSpec -> TcM Prag
-- Precondition: no duplicates
mkTcSigFun sigs = lookupNameEnv env
where
- env = mkNameEnv [(name, hsExplicitTvs lhs_ty)
- | L _ (TypeSig (L _ name) lhs_ty) <- sigs]
+ env = mkNameEnv (mapCatMaybes mk_pair sigs)
+ mk_pair (L _ (TypeSig (L _ name) lhs_ty)) = Just (name, hsExplicitTvs lhs_ty)
+ mk_pair (L _ (IdSig id)) = Just (idName id, [])
+ mk_pair _ = Nothing
-- The scoped names are the ones explicitly mentioned
-- in the HsForAll. (There may be more in sigma_ty, because
-- of nested type synonyms. See Note [More instantiated than scoped].)
= setSrcSpan span $
do { sigma_ty <- tcHsSigType (FunSigCtxt name) ty
; return (mkLocalId name sigma_ty) }
+tcTySig (L _ (IdSig id))
+ = return id
tcTySig s = pprPanic "tcTySig" (ppr s)
-------------------
}}}}}
tcLookupField :: Name -> TcM Id -- Returns the selector Id
-tcLookupField name = do
- thing <- tcLookup name -- Note [Record field lookup]
- case thing of
- AGlobal (AnId id) -> return id
- thing -> wrongThingErr "field name" thing name
+tcLookupField name
+ = tcLookupId name -- Note [Record field lookup]
{- Note [Record field lookup]
~~~~~~~~~~~~~~~~~~~~~~~~~~
; let { (local_info,
at_tycons_s) = unzip local_info_tycons
- ; at_idx_tycon = concat at_tycons_s ++ idx_tycons
+ ; at_idx_tycons = concat at_tycons_s ++ idx_tycons
; clas_decls = filter (isClassDecl.unLoc) tycl_decls
- ; implicit_things = concatMap implicitTyThings at_idx_tycon
+ ; implicit_things = concatMap implicitTyThings at_idx_tycons
+ ; aux_binds = mkAuxBinds at_idx_tycons
}
-- (2) Add the tycons of indexed types and their implicit
-- tythings to the global environment
- ; tcExtendGlobalEnv (at_idx_tycon ++ implicit_things) $ do {
+ ; tcExtendGlobalEnv (at_idx_tycons ++ implicit_things) $ do {
-- (3) Instances from generic class declarations
; generic_inst_info <- getGenericInstances clas_decls
-- c) local family instance decls
; addInsts local_info $ do {
; addInsts generic_inst_info $ do {
- ; addFamInsts at_idx_tycon $ do {
+ ; addFamInsts at_idx_tycons $ do {
-- (4) Compute instances from "deriving" clauses;
-- This stuff computes a context for the derived instance
-- more errors still
; (deriv_inst_info, deriv_binds) <- tcDeriving tycl_decls inst_decls
deriv_decls
- ; addInsts deriv_inst_info $ do {
-
- ; gbl_env <- getGblEnv
+ ; gbl_env <- addInsts deriv_inst_info getGblEnv
; return (gbl_env,
generic_inst_info ++ deriv_inst_info ++ local_info,
- deriv_binds)
- }}}}}}
+ aux_binds `plusHsValBinds` deriv_binds)
+ }}}}}
where
-- Make sure that toplevel type instance are not for associated types.
-- !!!TODO: Need to perform this check for the TyThing of type functions,
import {- Kind parts of -} Type
import BasicTypes
import Foreign.Ptr( Ptr )
+import TidyPgm ( globaliseAndTidyId )
#endif
import FastString
-- Typecheck them all together so that
-- any mutually recursive types are done right
- tcg_env <- tcTyAndClassDecls emptyModDetails rn_decls ;
- -- Make the new type env available to stuff slurped from interface files
+ -- Just discard the auxiliary bindings; they are generated
+ -- only for Haskell source code, and should already be in Core
+ (tcg_env, _aux_binds) <- tcTyAndClassDecls emptyModDetails rn_decls ;
setGblEnv tcg_env $ do {
+ -- Make the new type env available to stuff slurped from interface files
-- Now the core bindings
core_binds <- initIfaceExtCore (tcExtCoreBindings src_binds) ;
-- Typecheck type/class decls
; traceTc (text "Tc2")
- ; tcg_env <- tcTyAndClassDecls emptyModDetails tycl_decls
+ ; (tcg_env, aux_binds) <- tcTyAndClassDecls emptyModDetails tycl_decls
; setGblEnv tcg_env $ do {
-- Typecheck instance decls
-- Make the final type-env
-- Include the dfun_ids so that their type sigs
- -- are written into the interface file
+ -- are written into the interface file.
+ -- And similarly the aux_ids from aux_binds
; let { type_env0 = tcg_type_env gbl_env
; type_env1 = extendTypeEnvWithIds type_env0 val_ids
; type_env2 = extendTypeEnvWithIds type_env1 dfun_ids
- ; dfun_ids = map iDFunId inst_infos }
+ ; type_env3 = extendTypeEnvWithIds type_env1 aux_ids
+ ; dfun_ids = map iDFunId inst_infos
+ ; aux_ids = case aux_binds of
+ ValBindsOut _ sigs -> [id | L _ (IdSig id) <- sigs]
+ _ -> panic "tcRnHsBoodDecls"
+ }
+
; setGlobalTypeEnv gbl_env type_env2
}}}}
-- The latter come in via tycl_decls
traceTc (text "Tc2") ;
- tcg_env <- tcTyAndClassDecls boot_details tycl_decls ;
+ (tcg_env, aux_binds) <- tcTyAndClassDecls boot_details tycl_decls ;
-- If there are any errors, tcTyAndClassDecls fails here
setGblEnv tcg_env $ do {
<- tcInstDecls1 tycl_decls inst_decls deriv_decls;
setGblEnv tcg_env $ do {
- -- Foreign import declarations next. No zonking necessary
- -- here; we can tuck them straight into the global environment.
+ -- Foreign import declarations next.
traceTc (text "Tc4") ;
(fi_ids, fi_decls) <- tcForeignImports foreign_decls ;
tcExtendGlobalValEnv fi_ids $ do {
default_tys <- tcDefaults default_decls ;
updGblEnv (\gbl -> gbl { tcg_default = default_tys }) $ do {
+ -- Now GHC-generated derived bindings, generics, and selectors
+ -- Do not generate warnings from compiler-generated code;
+ -- hence the use of discardWarnings
+ (tc_aux_binds, tcl_env) <- discardWarnings (tcTopBinds aux_binds) ;
+ (tc_deriv_binds, tcl_env) <- setLclTypeEnv tcl_env $
+ discardWarnings (tcTopBinds deriv_binds) ;
+
-- Value declarations next
- -- We also typecheck any extra binds that came out
- -- of the "deriving" process (deriv_binds)
traceTc (text "Tc5") ;
- (tc_val_binds, tcl_env) <- tcTopBinds val_binds ;
- setLclTypeEnv tcl_env $ do {
-
- -- Now GHC-generated derived bindings and generics.
- -- Do not generate warnings from compiler-generated code.
- (tc_deriv_binds, tcl_env) <- discardWarnings $
- tcTopBinds deriv_binds ;
+ (tc_val_binds, tcl_env) <- setLclTypeEnv tcl_env $
+ tcTopBinds val_binds;
-- Second pass over class and instance declarations,
traceTc (text "Tc6") ;
- (inst_binds, tcl_env) <- setLclTypeEnv tcl_env $ tcInstDecls2 tycl_decls inst_infos ;
- showLIE (text "after instDecls2") ;
+ (inst_binds, tcl_env) <- setLclTypeEnv tcl_env $
+ tcInstDecls2 tycl_decls inst_infos ;
+ showLIE (text "after instDecls2") ;
+
+ setLclTypeEnv tcl_env $ do { -- Environment doesn't change now
-- Foreign exports
- -- They need to be zonked, so we return them
traceTc (text "Tc7") ;
(foe_binds, foe_decls) <- tcForeignExports foreign_decls ;
tcg_env <- getGblEnv ;
let { all_binds = tc_val_binds `unionBags`
tc_deriv_binds `unionBags`
+ tc_aux_binds `unionBags`
inst_binds `unionBags`
foe_binds;
mapM bad_unboxed (filter (isUnLiftedType . idType) zonked_ids) ;
traceTc (text "tcs 1") ;
- let { global_ids = map globaliseAndTidy zonked_ids } ;
-
+ let { global_ids = map globaliseAndTidyId zonked_ids } ;
+ -- Note [Interactively-bound Ids in GHCi]
+
{- ---------------------------------------------
At one stage I removed any shadowed bindings from the type_env;
they are inaccessible but might, I suppose, cause a space leak if we leave them there.
where
bad_unboxed id = addErr (sep [ptext (sLit "GHCi can't bind a variable of unlifted type:"),
nest 2 (ppr id <+> dcolon <+> ppr (idType id))])
-
-globaliseAndTidy :: Id -> Id
-globaliseAndTidy id -- Note [Interactively-bound Ids in GHCi]
- = Id.setIdType (globaliseId VanillaGlobal id) tidy_type
- where
- tidy_type = tidyTopType (idType id)
\end{code}
Note [Interactively-bound Ids in GHCi]
= do { ty <- reifyType (idType id)
; fix <- reifyFixity (idName id)
; let v = reifyName id
- ; case globalIdDetails id of
+ ; case idDetails id of
ClassOpId cls -> return (TH.ClassOpI v ty (reifyName cls) fix)
_ -> return (TH.VarI v ty Nothing fix)
}
\begin{code}
module TcTyClsDecls (
- tcTyAndClassDecls, tcFamInstDecl
+ tcTyAndClassDecls, tcFamInstDecl, mkAuxBinds
) where
#include "HsVersions.h"
import TcHsType
import TcMType
import TcType
+import TysWiredIn ( unitTy )
import FunDeps
import Type
import Generics
import TyCon
import DataCon
import Id
+import MkId ( rEC_SEL_ERROR_ID )
+import IdInfo
import Var
import VarSet
import Name
import Digraph
import DynFlags
import FastString
+import Unique ( mkBuiltinUnique )
+import BasicTypes
+import Bag
import Data.List
import Control.Monad ( mplus )
\end{code}
\begin{code}
tcTyAndClassDecls :: ModDetails -> [LTyClDecl Name]
- -> TcM TcGblEnv -- Input env extended by types and classes
- -- and their implicit Ids,DataCons
+ -> TcM (TcGblEnv, -- Input env extended by types and classes
+ -- and their implicit Ids,DataCons
+ HsValBinds Name) -- Renamed bindings for record selectors
-- Fails if there are any errors
tcTyAndClassDecls boot_details allDecls
-- NB: All associated types and their implicit things will be added a
-- second time here. This doesn't matter as the definitions are
-- the same.
- ; let { implicit_things = concatMap implicitTyThings alg_tyclss }
+ ; let { implicit_things = concatMap implicitTyThings alg_tyclss
+ ; aux_binds = mkAuxBinds alg_tyclss }
; traceTc ((text "Adding" <+> ppr alg_tyclss)
$$ (text "and" <+> ppr implicit_things))
- ; tcExtendGlobalEnv implicit_things getGblEnv
- }}
+ ; env <- tcExtendGlobalEnv implicit_things getGblEnv
+ ; return (env, aux_binds) }
+ }
where
-- Pull associated types out of class declarations, to tie them into the
-- knot above.
%************************************************************************
%* *
-\subsection{Type checking family instances}
+ Type checking family instances
%* *
%************************************************************************
-- * Here we check that a type instance matches its kind signature, but we do
-- not check whether there is a pattern for each type index; the latter
-- check is only required for type synonym instances.
---
+
kcIdxTyPats :: TyClDecl Name
-> ([LHsTyVarBndr Name] -> [LHsType Name] -> Kind -> TyCon -> TcM a)
-- ^^kinded tvs ^^kinded ty pats ^^res kind
-- In this case orig_res_ty = T (e,e)
tcResultType :: ([TyVar], Type) -- Template for result type; e.g.
- -- data T a b c = ... gives ([a,b,c], T a b)
- -> [TyVar] -- where MkT :: forall a b c. ...
+ -- data instance T [a] b c = ...
+ -- gives template ([a,b,c], T [a] b c)
+ -> [TyVar] -- where MkT :: forall x y z. ...
-> ResType Name
-> TcM ([TyVar], -- Universal
[TyVar], -- Existential (distinct OccNames from univs)
-- b b~z
-- z
-- Existentials are the leftover type vars: [x,y]
+ -- So we return ([a,b,z], [x,y], [a~(x,y),b~z], T [(x,y)] z z)
= do { res_ty' <- tcHsKindedType res_ty
; let Just subst = tcMatchTy (mkVarSet tmpl_tvs) res_tmpl res_ty'
data S = MkS S !Int
because Int is non-recursive.
+
%************************************************************************
%* *
-\subsection{Dependency analysis}
+ Validity checking
%* *
%************************************************************************
-- forall has an (Eq a) constraint. Whereas in general, each constraint
-- in the context of a for-all must mention at least one quantified
-- type variable. What a mess!
+\end{code}
+
+
+%************************************************************************
+%* *
+ Building record selectors
+%* *
+%************************************************************************
+
+\begin{code}
+mkAuxBinds :: [TyThing] -> HsValBinds Name
+mkAuxBinds ty_things
+ = ValBindsOut [(NonRecursive, b) | b <- binds] sigs
+ where
+ (sigs, binds) = unzip rec_sels
+ rec_sels = map mkRecSelBind [ (tc,fld)
+ | ATyCon tc <- ty_things
+ , fld <- tyConFields tc ]
----------------------------------------------------------------------
+mkRecSelBind :: (TyCon, FieldLabel) -> (LSig Name, LHsBinds Name)
+mkRecSelBind (tycon, sel_name)
+ = (L loc (IdSig sel_id), unitBag (L loc sel_bind))
+ where
+ loc = getSrcSpan tycon
+ sel_id = Var.mkLocalVar rec_details sel_name sel_ty vanillaIdInfo
+ rec_details = RecSelId { sel_tycon = tycon, sel_naughty = is_naughty }
+
+ -- Find a representative constructor, con1
+ all_cons = tyConDataCons tycon
+ cons_w_field = [ con | con <- all_cons
+ , sel_name `elem` dataConFieldLabels con ]
+ con1 = ASSERT( not (null cons_w_field) ) head cons_w_field
+
+ -- Selector type; Note [Polymorphic selectors]
+ field_ty = dataConFieldType con1 sel_name
+ (field_tvs, field_theta, field_tau)
+ | is_naughty = ([], [], unitTy)
+ | otherwise = tcSplitSigmaTy field_ty
+ data_ty = dataConOrigResTy con1
+ data_tvs = tyVarsOfType data_ty
+ is_naughty = not (tyVarsOfType field_ty `subVarSet` data_tvs)
+ sel_ty = mkForAllTys (varSetElems data_tvs ++ field_tvs) $
+ mkPhiTy (dataConStupidTheta con1) $ -- Urgh!
+ mkPhiTy field_theta $ -- Urgh!
+ mkFunTy data_ty field_tau
+
+ -- Make the binding: sel (C2 { fld = x }) = x
+ -- sel (C7 { fld = x }) = x
+ -- where cons_w_field = [C2,C7]
+ sel_bind = mkFunBind sel_lname (map mk_match cons_w_field ++ deflt)
+ mk_match con = mkSimpleMatch [L loc (mk_sel_pat con)]
+ (L loc match_body)
+ mk_sel_pat con = ConPatIn (L loc (getName con)) (RecCon rec_fields)
+ rec_fields = HsRecFields { rec_flds = [rec_field], rec_dotdot = Nothing }
+ rec_field = HsRecField { hsRecFieldId = sel_lname
+ , hsRecFieldArg = nlVarPat field_var
+ , hsRecPun = False }
+ match_body | is_naughty = ExplicitTuple [] Boxed
+ | otherwise = HsVar field_var
+ sel_lname = L loc sel_name
+ field_var = mkInternalName (mkBuiltinUnique 1) (getOccName sel_name) loc
+
+ -- Add catch-all default case unless the case is exhaustive
+ -- We do this explicitly so that we get a nice error message that
+ -- mentions this particular record selector
+ deflt | length cons_w_field == length all_cons = []
+ | otherwise = [mkSimpleMatch [nlWildPat]
+ (nlHsApp (nlHsVar (getName rEC_SEL_ERROR_ID))
+ (nlHsLit msg_lit))]
+ msg_lit = HsStringPrim $ mkFastString $
+ occNameString (getOccName sel_name)
+
+---------------
+tyConFields :: TyCon -> [FieldLabel]
+tyConFields tc
+ | isAlgTyCon tc = nub (concatMap dataConFieldLabels (tyConDataCons tc))
+ | otherwise = []
+\end{code}
+
+Note [Polymorphic selectors]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+When a record has a polymorphic field, we pull the foralls out to the front.
+ data T = MkT { f :: forall a. [a] -> a }
+Then f :: forall a. T -> [a] -> a
+NOT f :: T -> forall a. [a] -> a
+
+This is horrid. It's only needed in deeply obscure cases, which I hate.
+The only case I know is test tc163, which is worth looking at. It's far
+from clear that this test should succeed at all!
+
+Note [Naughty record selectors]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+A "naughty" field is one for which we can't define a record
+selector, because an existential type variable would escape. For example:
+ data T = forall a. MkT { x,y::a }
+We obviously can't define
+ x (MkT v _) = v
+Nevertheless we *do* put a RecSelId into the type environment
+so that if the user tries to use 'x' as a selector we can bleat
+helpfully, rather than saying unhelpfully that 'x' is not in scope.
+Hence the sel_naughty flag, to identify record selectors that don't really exist.
+
+In general, a field is naughty if its type mentions a type variable that
+isn't in the result type of the constructor.
+
+We make a dummy binding for naughty selectors, so that they can be treated
+uniformly, apart from their sel_naughty field. The function is never called.
+
+Note [GADT record selectors]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+For GADTs, we require that all constructors with a common field 'f' have the same
+result type (modulo alpha conversion). [Checked in TcTyClsDecls.checkValidTyCon]
+E.g.
+ data T where
+ T1 { f :: Maybe a } :: T [a]
+ T2 { f :: Maybe a, y :: b } :: T [a]
+
+and now the selector takes that result type as its argument:
+ f :: forall a. T [a] -> Maybe a
+
+Details: the "real" types of T1,T2 are:
+ T1 :: forall r a. (r~[a]) => a -> T r
+ T2 :: forall r a b. (r~[a]) => a -> b -> T r
+
+So the selector loooks like this:
+ f :: forall a. T [a] -> Maybe a
+ f (a:*) (t:T [a])
+ = case t of
+ T1 c (g:[a]~[c]) (v:Maybe c) -> v `cast` Maybe (right (sym g))
+ T2 c d (g:[a]~[c]) (v:Maybe c) (w:d) -> v `cast` Maybe (right (sym g))
+
+Note the forall'd tyvars of the selector are just the free tyvars
+of the result type; there may be other tyvars in the constructor's
+type (e.g. 'b' in T2).
+
+Note the need for casts in the result!
+
+Note [Selector running example]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+It's OK to combine GADTs and type families. Here's a running example:
+
+ data instance T [a] where
+ T1 { fld :: b } :: T [Maybe b]
+
+The representation type looks like this
+ data :R7T a where
+ T1 { fld :: b } :: :R7T (Maybe b)
+
+and there's coercion from the family type to the representation type
+ :CoR7T a :: T [a] ~ :R7T a
+
+The selector we want for fld looks like this:
+
+ fld :: forall b. T [Maybe b] -> b
+ fld = /\b. \(d::T [Maybe b]).
+ case d `cast` :CoR7T (Maybe b) of
+ T1 (x::b) -> x
+
+The scrutinee of the case has type :R7T (Maybe b), which can be
+gotten by appying the eq_spec to the univ_tvs of the data con.
+
+%************************************************************************
+%* *
+ Error messages
+%* *
+%************************************************************************
+
+\begin{code}
resultTypeMisMatch :: Name -> DataCon -> DataCon -> SDoc
resultTypeMisMatch field_name con1 con2
= vcat [sep [ptext (sLit "Constructors") <+> ppr con1 <+> ptext (sLit "and") <+> ppr con2,
quotes (ppr tc_name)
, nest 2 (parens $ ptext (sLit "Use -XTypeFamilies to allow indexed type families")) ]
-{-
-badGadtIdxTyDecl :: Name -> SDoc
-badGadtIdxTyDecl tc_name
- = vcat [ ptext (sLit "Illegal generalised algebraic data declaration for") <+>
- quotes (ppr tc_name)
- , nest 2 (parens $ ptext (sLit "Family instances can not yet use GADT declarations")) ]
--}
tooManyParmsErr :: Located Name -> SDoc
tooManyParmsErr tc_name
= ptext (sLit "Family instance has too many parameters:") <+>
tyConTyVars,
tyConDataCons, tyConDataCons_maybe, tyConSingleDataCon_maybe,
tyConFamilySize,
- tyConSelIds,
tyConStupidTheta,
tyConArity,
tyConClass_maybe,
--
-- Note that it does /not/ scope over the data constructors.
- algTcSelIds :: [Id], -- ^ The record selectors of this type (possibly emptys)
-
algTcGadtSyntax :: Bool, -- ^ Was the data type declared with GADT syntax? If so,
-- that doesn't mean it's a true GADT; only that the "where"
-- form was used. This field is used only to guide
-> [TyVar] -- ^ 'TyVar's scoped over: see 'tyConTyVars'. Arity is inferred from the length of this list
-> [PredType] -- ^ Stupid theta: see 'algTcStupidTheta'
-> AlgTyConRhs -- ^ Information about dat aconstructors
- -> [Id] -- ^ Selector 'Id's
-> TyConParent
-> RecFlag -- ^ Is the 'TyCon' recursive?
-> Bool -- ^ Does it have generic functions? See 'hasGenerics'
-> Bool -- ^ Was the 'TyCon' declared with GADT syntax?
-> TyCon
-mkAlgTyCon name kind tyvars stupid rhs sel_ids parent is_rec gen_info gadt_syn
+mkAlgTyCon name kind tyvars stupid rhs parent is_rec gen_info gadt_syn
= AlgTyCon {
tyConName = name,
tyConUnique = nameUnique name,
tyConTyVars = tyvars,
algTcStupidTheta = stupid,
algTcRhs = rhs,
- algTcSelIds = sel_ids,
algTcParent = ASSERT( okParent name parent ) parent,
algTcRec = is_rec,
algTcGadtSyntax = gadt_syn,
-- | Simpler specialization of 'mkAlgTyCon' for classes
mkClassTyCon :: Name -> Kind -> [TyVar] -> AlgTyConRhs -> Class -> RecFlag -> TyCon
mkClassTyCon name kind tyvars rhs clas is_rec =
- mkAlgTyCon name kind tyvars [] rhs [] (ClassTyCon clas) is_rec False False
+ mkAlgTyCon name kind tyvars [] rhs (ClassTyCon clas) is_rec False False
mkTupleTyCon :: Name
-> Kind -- ^ Kind of the resulting 'TyCon'
tyConFamilySize (TupleTyCon {}) = 1
tyConFamilySize other = pprPanic "tyConFamilySize:" (ppr other)
--- | Extract the record selector 'Id's from an algebraic 'TyCon' and returns the empty list otherwise
-tyConSelIds :: TyCon -> [Id]
-tyConSelIds (AlgTyCon {algTcSelIds = fs}) = fs
-tyConSelIds _ = []
-
-- | Extract an 'AlgTyConRhs' with information about data constructors from an algebraic or tuple
-- 'TyCon'. Panics for any other sort of 'TyCon'
algTyConRhs :: TyCon -> AlgTyConRhs
collectAnnValBinders :: AnnExpr Var ann -> ([Var], AnnExpr Var ann)
collectAnnValBinders expr = go [] expr
where
- go bs (_, AnnLam b e) | isIdVar b = go (b:bs) e
- go bs e = (reverse bs, e)
+ go bs (_, AnnLam b e) | isId b = go (b:bs) e
+ go bs e = (reverse bs, e)
isAnnTypeArg :: AnnExpr b ann -> Bool
isAnnTypeArg (_, AnnType _) = True
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