getClassPredTys_maybe, getClassPredTys,
isClassPred, isTyVarClassPred, isEqPred,
mkDictTy, tcSplitPredTy_maybe,
- isPredTy, isDictTy, tcSplitDFunTy, tcSplitDFunHead, predTyUnique,
+ isPredTy, isDictTy, isDictLikeTy,
+ tcSplitDFunTy, tcSplitDFunHead, predTyUnique,
mkClassPred, isInheritablePred, isIPPred,
- dataConsStupidTheta, isRefineableTy, isRefineablePred,
+ isRefineableTy, isRefineablePred,
---------------------------------
-- Foreign import and export
isFFIExternalTy, -- :: Type -> Bool
isFFIDynArgumentTy, -- :: Type -> Bool
isFFIDynResultTy, -- :: Type -> Bool
+ isFFIPrimArgumentTy, -- :: DynFlags -> Type -> Bool
+ isFFIPrimResultTy, -- :: DynFlags -> Type -> Bool
isFFILabelTy, -- :: Type -> Bool
isFFIDotnetTy, -- :: DynFlags -> Type -> Bool
isFFIDotnetObjTy, -- :: Type -> Bool
unliftedTypeKind, liftedTypeKind, argTypeKind,
openTypeKind, mkArrowKind, mkArrowKinds,
isLiftedTypeKind, isUnliftedTypeKind, isSubOpenTypeKind,
- isSubArgTypeKind, isSubKind, defaultKind,
+ isSubArgTypeKind, isSubKind, splitKindFunTys, defaultKind,
kindVarRef, mkKindVar,
Type, PredType(..), ThetaType,
typeKind, tidyKind,
tyVarsOfType, tyVarsOfTypes, tyVarsOfPred, tyVarsOfTheta,
- tcTyVarsOfType, tcTyVarsOfTypes, exactTyVarsOfType, exactTyVarsOfTypes,
+ tcTyVarsOfType, tcTyVarsOfTypes, tcTyVarsOfPred, exactTyVarsOfType,
+ exactTyVarsOfTypes,
pprKind, pprParendKind,
pprType, pprParendType, pprTypeApp, pprTyThingCategory,
import Class
import Var
import ForeignCall
-import Unify
import VarSet
import Type
import Coercion
import Name
import NameSet
import VarEnv
-import OccName
import PrelNames
import TysWiredIn
import BasicTypes
import Outputable
import FastString
-import Data.List
import Data.IORef
\end{code}
| ForSigCtxt Name -- Foreign inport or export signature
| DefaultDeclCtxt -- Types in a default declaration
| SpecInstCtxt -- SPECIALISE instance pragma
+ | ThBrackCtxt -- Template Haskell type brackets [t| ... |]
-- Notes re TySynCtxt
-- We allow type synonyms that aren't types; e.g. type List = []
pprUserTypeCtxt (ConArgCtxt c) = ptext (sLit "the type of the constructor") <+> quotes (ppr c)
pprUserTypeCtxt (TySynCtxt c) = ptext (sLit "the RHS of the type synonym") <+> quotes (ppr c)
pprUserTypeCtxt GenPatCtxt = ptext (sLit "the type pattern of a generic definition")
+pprUserTypeCtxt ThBrackCtxt = ptext (sLit "a Template Haskell quotation [t|...|]")
pprUserTypeCtxt LamPatSigCtxt = ptext (sLit "a pattern type signature")
pprUserTypeCtxt BindPatSigCtxt = ptext (sLit "a pattern type signature")
pprUserTypeCtxt ResSigCtxt = ptext (sLit "a result type signature")
isDictTy ty | Just ty' <- tcView ty = isDictTy ty'
isDictTy (PredTy p) = isClassPred p
isDictTy _ = False
+
+isDictLikeTy :: Type -> Bool
+-- Note [Dictionary-like types]
+isDictLikeTy ty | Just ty' <- tcView ty = isDictTy ty'
+isDictLikeTy (PredTy p) = isClassPred p
+isDictLikeTy (TyConApp tc tys)
+ | isTupleTyCon tc = all isDictLikeTy tys
+isDictLikeTy _ = False
\end{code}
+Note [Dictionary-like types]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Being "dictionary-like" means either a dictionary type or a tuple thereof.
+In GHC 6.10 we build implication constraints which construct such tuples,
+and if we land up with a binding
+ t :: (C [a], Eq [a])
+ t = blah
+then we want to treat t as cheap under "-fdicts-cheap" for example.
+(Implication constraints are normally inlined, but sadly not if the
+occurrence is itself inside an INLINE function! Until we revise the
+handling of implication constraints, that is.) This turned out to
+be important in getting good arities in DPH code. Example:
+
+ class C a
+ class D a where { foo :: a -> a }
+ instance C a => D (Maybe a) where { foo x = x }
+
+ bar :: (C a, C b) => a -> b -> (Maybe a, Maybe b)
+ {-# INLINE bar #-}
+ bar x y = (foo (Just x), foo (Just y))
+
+Then 'bar' should jolly well have arity 4 (two dicts, two args), but
+we ended up with something like
+ bar = __inline_me__ (\d1,d2. let t :: (D (Maybe a), D (Maybe b)) = ...
+ in \x,y. <blah>)
+
+This is all a bit ad-hoc; eg it relies on knowing that implication
+constraints build tuples.
+
--------------------- Implicit parameters ---------------------------------
\begin{code}
| (tv,ty) <- eq_spec]
\end{code}
---------------------- The stupid theta (sigh) ---------------------------------
-
-\begin{code}
-dataConsStupidTheta :: [DataCon] -> ThetaType
--- Union the stupid thetas from all the specified constructors (non-empty)
--- All the constructors should have the same result type, modulo alpha conversion
--- The resulting ThetaType uses type variables from the *first* constructor in the list
---
--- It's here because it's used in MkId.mkRecordSelId, and in TcExpr
-dataConsStupidTheta (con1:cons)
- = nubBy tcEqPred all_preds
- where
- all_preds = dataConStupidTheta con1 ++ other_stupids
- res_ty1 = dataConOrigResTy con1
- other_stupids = [ substPred subst pred
- | con <- cons
- , let (tvs, _, _, res_ty) = dataConSig con
- Just subst = tcMatchTy (mkVarSet tvs) res_ty res_ty1
- , pred <- dataConStupidTheta con ]
-dataConsStupidTheta [] = panic "dataConsStupidTheta"
-\end{code}
-
%************************************************************************
%* *
-- or a newtype of either.
isFFILabelTy = checkRepTyConKey [ptrTyConKey, funPtrTyConKey]
+isFFIPrimArgumentTy :: DynFlags -> Type -> Bool
+-- Checks for valid argument type for a 'foreign import prim'
+-- Currently they must all be simple unlifted types.
+isFFIPrimArgumentTy dflags ty
+ = checkRepTyCon (legalFIPrimArgTyCon dflags) ty
+
+isFFIPrimResultTy :: DynFlags -> Type -> Bool
+-- Checks for valid result type for a 'foreign import prim'
+-- Currently it must be an unlifted type, including unboxed tuples.
+isFFIPrimResultTy dflags ty
+ = checkRepTyCon (legalFIPrimResultTyCon dflags) ty
+
isFFIDotnetTy :: DynFlags -> Type -> Bool
isFFIDotnetTy dflags ty
= checkRepTyCon (\ tc -> (legalFIResultTyCon dflags tc ||
, stablePtrTyConKey
, boolTyConKey
]
+
+legalFIPrimArgTyCon :: DynFlags -> TyCon -> Bool
+-- Check args of 'foreign import prim', only allow simple unlifted types.
+-- Strictly speaking it is unnecessary to ban unboxed tuples here since
+-- currently they're of the wrong kind to use in function args anyway.
+legalFIPrimArgTyCon dflags tc
+ = dopt Opt_UnliftedFFITypes dflags
+ && isUnLiftedTyCon tc
+ && not (isUnboxedTupleTyCon tc)
+
+legalFIPrimResultTyCon :: DynFlags -> TyCon -> Bool
+-- Check result type of 'foreign import prim'. Allow simple unlifted
+-- types and also unboxed tuple result types '... -> (# , , #)'
+legalFIPrimResultTyCon dflags tc
+ = dopt Opt_UnliftedFFITypes dflags
+ && isUnLiftedTyCon tc
+ && (isUnboxedTupleTyCon tc
+ || case tyConPrimRep tc of -- Note [Marshalling VoidRep]
+ VoidRep -> False
+ _ -> True)
\end{code}
Note [Marshalling VoidRep]
projects / ghc-hetmet.git / blobdiff