X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Fghci%2FRtClosureInspect.hs;h=ea882d5cab55444f7dc220e7b6ce60a2f758e66b;hb=a4d1f3a5a560ee8f4cbf32e2d6a9e9d158c8d8ee;hp=cafa527d216796e0962e9b637473dbc768f3f94a;hpb=a27d12f02b8ab3a3222c351dcf7e9168dfe05fb0;p=ghc-hetmet.git diff --git a/compiler/ghci/RtClosureInspect.hs b/compiler/ghci/RtClosureInspect.hs index cafa527..ea882d5 100644 --- a/compiler/ghci/RtClosureInspect.hs +++ b/compiler/ghci/RtClosureInspect.hs @@ -11,9 +11,13 @@ module RtClosureInspect( cvObtainTerm, -- :: HscEnv -> Int -> Bool -> Maybe Type -> HValue -> IO Term Term(..), + isTerm, + isSuspension, + isPrim, pprTerm, cPprTerm, cPprTermBase, + CustomTermPrinter, termType, foldTerm, TermFold(..), @@ -27,7 +31,12 @@ module RtClosureInspect( -- unsafeDeepSeq, cvReconstructType, computeRTTIsubst, - sigmaType + sigmaType, + Closure(..), + getClosureData, + ClosureType(..), + isConstr, + isIndirection ) where #include "HsVersions.h" @@ -37,23 +46,24 @@ import qualified ByteCodeItbls as BCI( StgInfoTable(..) ) import HscTypes ( HscEnv ) import Linker -import DataCon -import Type -import TcRnMonad ( TcM, initTc, initTcPrintErrors, ioToTcRn, - tryTcErrs) +import DataCon +import Type +import Var +import TcRnMonad ( TcM, initTc, ioToTcRn, + tryTcErrs, traceTc) import TcType import TcMType import TcUnify import TcGadt import TcEnv import DriverPhases -import TyCon -import Name +import TyCon +import Name import VarEnv import Util import VarSet -import TysPrim +import TysPrim import PrelNames import TysWiredIn @@ -68,8 +78,11 @@ import GHC.Exts import Control.Monad import Data.Maybe import Data.Array.Base +import Data.Ix import Data.List ( partition ) import qualified Data.Sequence as Seq +import Data.Monoid +import Data.Sequence hiding (null, length, index, take, drop, splitAt, reverse) import Foreign import System.IO.Unsafe @@ -90,8 +103,6 @@ import System.IO.Unsafe data Term = Term { ty :: Type , dc :: Either String DataCon - -- The heap datacon. If ty is a newtype, - -- this is NOT the newtype datacon. -- Empty if the datacon aint exported by the .hi -- (private constructors in -O0 libraries) , val :: HValue @@ -105,14 +116,19 @@ data Term = Term { ty :: Type , val :: HValue , bound_to :: Maybe Name -- Useful for printing } + | NewtypeWrap{ ty :: Type + , dc :: Either String DataCon + , wrapped_term :: Term } -isTerm, isSuspension, isPrim :: Term -> Bool +isTerm, isSuspension, isPrim, isNewtypeWrap :: Term -> Bool isTerm Term{} = True isTerm _ = False isSuspension Suspension{} = True isSuspension _ = False isPrim Prim{} = True isPrim _ = False +isNewtypeWrap NewtypeWrap{} = True +isNewtypeWrap _ = False termType :: Term -> Maybe Type termType t@(Suspension {}) = mb_ty t @@ -120,8 +136,9 @@ termType t = Just$ ty t isFullyEvaluatedTerm :: Term -> Bool isFullyEvaluatedTerm Term {subTerms=tt} = all isFullyEvaluatedTerm tt -isFullyEvaluatedTerm Suspension {} = False isFullyEvaluatedTerm Prim {} = True +isFullyEvaluatedTerm NewtypeWrap{wrapped_term=t} = isFullyEvaluatedTerm t +isFullyEvaluatedTerm _ = False instance Outputable (Term) where ppr = head . cPprTerm cPprTermBase @@ -152,6 +169,7 @@ instance Outputable ClosureType where #include "../includes/ClosureTypes.h" +aP_CODE, pAP_CODE :: Int aP_CODE = AP pAP_CODE = PAP #undef AP @@ -161,13 +179,21 @@ getClosureData :: a -> IO Closure getClosureData a = case unpackClosure# a of (# iptr, ptrs, nptrs #) -> do +#ifndef GHCI_TABLES_NEXT_TO_CODE + -- the info pointer we get back from unpackClosure# is to the + -- beginning of the standard info table, but the Storable instance + -- for info tables takes into account the extra entry pointer + -- when !tablesNextToCode, so we must adjust here: + itbl <- peek (Ptr iptr `plusPtr` negate wORD_SIZE) +#else itbl <- peek (Ptr iptr) +#endif let tipe = readCType (BCI.tipe itbl) elems = fromIntegral (BCI.ptrs itbl) ptrsList = Array 0 (elems - 1) elems ptrs nptrs_data = [W# (indexWordArray# nptrs i) | I# i <- [0.. fromIntegral (BCI.nptrs itbl)] ] - ASSERT(fromIntegral elems >= 0) return () + ASSERT(elems >= 0) return () ptrsList `seq` return (Closure tipe (Ptr iptr) itbl ptrsList nptrs_data) @@ -203,9 +229,10 @@ isFullyEvaluated a = do case tipe closure of Constr -> do are_subs_evaluated <- amapM isFullyEvaluated (ptrs closure) return$ and are_subs_evaluated - otherwise -> return False + _ -> return False where amapM f = sequence . amap' f +amap' :: (t -> b) -> Array Int t -> [b] amap' f (Array i0 i _ arr#) = map g [0 .. i - i0] where g (I# i#) = case indexArray# arr# i# of (# e #) -> f e @@ -238,41 +265,49 @@ extractUnboxed tt clos = go tt (nonPtrs clos) | (x, rest) <- splitAt ((sizeofType t + wORD_SIZE - 1) `div` wORD_SIZE) xx = x : go tt rest +sizeofTyCon :: TyCon -> Int sizeofTyCon = sizeofPrimRep . tyConPrimRep ----------------------------------- -- * Traversals for Terms ----------------------------------- +type TermProcessor a b = Type -> Either String DataCon -> HValue -> [a] -> b -data TermFold a = TermFold { fTerm :: Type -> Either String DataCon -> HValue -> [a] -> a +data TermFold a = TermFold { fTerm :: TermProcessor a a , fPrim :: Type -> [Word] -> a , fSuspension :: ClosureType -> Maybe Type -> HValue -> Maybe Name -> a + , fNewtypeWrap :: Type -> Either String DataCon + -> a -> a } foldTerm :: TermFold a -> Term -> a foldTerm tf (Term ty dc v tt) = fTerm tf ty dc v (map (foldTerm tf) tt) foldTerm tf (Prim ty v ) = fPrim tf ty v foldTerm tf (Suspension ct ty v b) = fSuspension tf ct ty v b +foldTerm tf (NewtypeWrap ty dc t) = fNewtypeWrap tf ty dc (foldTerm tf t) idTermFold :: TermFold Term idTermFold = TermFold { fTerm = Term, fPrim = Prim, - fSuspension = Suspension + fSuspension = Suspension, + fNewtypeWrap = NewtypeWrap } idTermFoldM :: Monad m => TermFold (m Term) idTermFoldM = TermFold { fTerm = \ty dc v tt -> sequence tt >>= return . Term ty dc v, fPrim = (return.). Prim, - fSuspension = (((return.).).). Suspension + fSuspension = (((return.).).). Suspension, + fNewtypeWrap= \ty dc t -> NewtypeWrap ty dc `liftM` t } mapTermType :: (Type -> Type) -> Term -> Term mapTermType f = foldTerm idTermFold { fTerm = \ty dc hval tt -> Term (f ty) dc hval tt, fSuspension = \ct mb_ty hval n -> - Suspension ct (fmap f mb_ty) hval n } + Suspension ct (fmap f mb_ty) hval n, + fNewtypeWrap= \ty dc t -> NewtypeWrap (f ty) dc t} termTyVars :: Term -> TyVarSet termTyVars = foldTerm TermFold { @@ -280,8 +315,10 @@ termTyVars = foldTerm TermFold { tyVarsOfType ty `plusVarEnv` concatVarEnv tt, fSuspension = \_ mb_ty _ _ -> maybe emptyVarEnv tyVarsOfType mb_ty, - fPrim = \ _ _ -> emptyVarEnv } + fPrim = \ _ _ -> emptyVarEnv, + fNewtypeWrap= \ty _ t -> tyVarsOfType ty `plusVarEnv` t} where concatVarEnv = foldr plusVarEnv emptyVarEnv + ---------------------------------- -- Pretty printing of terms ---------------------------------- @@ -290,92 +327,134 @@ app_prec,cons_prec ::Int app_prec = 10 cons_prec = 5 -- TODO Extract this info from GHC itself +pprTerm :: (Int -> Term -> Maybe SDoc) -> Int -> Term -> SDoc pprTerm y p t | Just doc <- pprTermM y p t = doc +pprTerm _ _ _ = panic "pprTerm" -pprTermM :: Monad m => (Int -> Term -> m SDoc) -> Int -> Term -> m SDoc -pprTermM y p t@Term{dc=Left dc_tag, subTerms=tt, ty=ty} = do +pprTermM, pprNewtypeWrap :: Monad m => + (Int -> Term -> m SDoc) -> Int -> Term -> m SDoc +pprTermM y p Term{dc=Left dc_tag, subTerms=tt} = do tt_docs <- mapM (y app_prec) tt - return$ cparen (not(null tt) && p >= app_prec) (text dc_tag <+> sep tt_docs) + return$ cparen (not(null tt) && p >= app_prec) (text dc_tag <+> fsep tt_docs) -pprTermM y p t@Term{dc=Right dc, subTerms=tt, ty=ty} +pprTermM y p Term{dc=Right dc, subTerms=tt} {- | dataConIsInfix dc, (t1:t2:tt') <- tt --TODO fixity = parens (pprTerm1 True t1 <+> ppr dc <+> pprTerm1 True ppr t2) <+> hsep (map (pprTerm1 True) tt) -} -- TODO Printing infix constructors properly | null tt = return$ ppr dc - | Just (tc,_) <- splitNewTyConApp_maybe ty - , isNewTyCon tc - , Just new_dc <- maybeTyConSingleCon tc = do - real_value <- y 10 t{ty=repType ty} - return$ cparen (p >= app_prec) (ppr new_dc <+> real_value) | otherwise = do tt_docs <- mapM (y app_prec) tt - return$ cparen (p >= app_prec) (ppr dc <+> sep tt_docs) + return$ cparen (p >= app_prec) (ppr dc <+> fsep tt_docs) -pprTermM y _ t = pprTermM1 y t -pprTermM1 _ Prim{value=words, ty=ty} = +pprTermM y p t@NewtypeWrap{} = pprNewtypeWrap y p t + +pprTermM _ _ t = pprTermM1 t + +pprTermM1 :: Monad m => Term -> m SDoc +pprTermM1 Prim{value=words, ty=ty} = return$ text$ repPrim (tyConAppTyCon ty) words -pprTermM1 y t@Term{} = panic "pprTermM1 - unreachable" -pprTermM1 _ Suspension{bound_to=Nothing} = return$ char '_' -pprTermM1 _ Suspension{mb_ty=Just ty, bound_to=Just n} +pprTermM1 Term{} = panic "pprTermM1 - unreachable" +pprTermM1 Suspension{bound_to=Nothing} = return$ char '_' +pprTermM1 Suspension{mb_ty=Just ty, bound_to=Just n} | Just _ <- splitFunTy_maybe ty = return$ ptext SLIT("") | otherwise = return$ parens$ ppr n <> text "::" <> ppr ty +pprTermM1 _ = panic "pprTermM1" + +pprNewtypeWrap y p NewtypeWrap{ty=ty, wrapped_term=t} + | Just (tc,_) <- splitNewTyConApp_maybe ty + , ASSERT(isNewTyCon tc) True + , Just new_dc <- maybeTyConSingleCon tc = do + real_term <- y 10 t + return$ cparen (p >= app_prec) (ppr new_dc <+> real_term) +pprNewtypeWrap _ _ _ = panic "pprNewtypeWrap" + +------------------------------------------------------- +-- Custom Term Pretty Printers +------------------------------------------------------- + +-- We can want to customize the representation of a +-- term depending on its type. +-- However, note that custom printers have to work with +-- type representations, instead of directly with types. +-- We cannot use type classes here, unless we employ some +-- typerep trickery (e.g. Weirich's RepLib tricks), +-- which I didn't. Therefore, this code replicates a lot +-- of what type classes provide for free. + +-- Concretely a custom term printer takes an explicit +-- recursion knot, and produces a list of Term Processors, +-- which additionally need a precedence value to +-- either produce a SDoc or fail (and they do this in some monad m). + +type Precedence = Int +type RecursionKnot m = Precedence -> Term -> m SDoc +type CustomTermPrinter m = RecursionKnot m + -> [Precedence -> Term -> (m (Maybe SDoc))] -- Takes a list of custom printers with a explicit recursion knot and a term, -- and returns the output of the first succesful printer, or the default printer -cPprTerm :: forall m. Monad m => - ((Int->Term->m SDoc)->[Int->Term->m (Maybe SDoc)]) -> Term -> m SDoc -cPprTerm custom = go 0 where - go prec t@Term{} = do - let default_ prec t = Just `liftM` pprTermM go prec t - mb_customDocs = [pp prec t | pp <- custom go ++ [default_]] +cPprTerm :: Monad m => CustomTermPrinter m -> Term -> m SDoc +cPprTerm printers_ = go 0 where + printers = printers_ go + go prec t | isTerm t || isNewtypeWrap t = do + let default_ = Just `liftM` pprTermM go prec t + mb_customDocs = [pp prec t | pp <- printers] ++ [default_] Just doc <- firstJustM mb_customDocs return$ cparen (prec>app_prec+1) doc - go _ t = pprTermM1 go t + go _ t = pprTermM1 t + firstJustM (mb:mbs) = mb >>= maybe (firstJustM mbs) (return . Just) firstJustM [] = return Nothing -- Default set of custom printers. Note that the recursion knot is explicit -cPprTermBase :: Monad m => (Int->Term-> m SDoc)->[Int->Term->m (Maybe SDoc)] +cPprTermBase :: Monad m => CustomTermPrinter m cPprTermBase y = - [ - ifTerm isTupleTy (\_ -> liftM (parens . hcat . punctuate comma) - . mapM (y (-1)) . subTerms) - , ifTerm (\t -> isTyCon listTyCon t && subTerms t `lengthIs` 2) - (\ p Term{subTerms=[h,t]} -> doList p h t) - , ifTerm (isTyCon intTyCon) (coerceShow$ \(a::Int)->a) - , ifTerm (isTyCon charTyCon) (coerceShow$ \(a::Char)->a) --- , ifTerm (isTyCon wordTyCon) (coerceShow$ \(a::Word)->a) - , ifTerm (isTyCon floatTyCon) (coerceShow$ \(a::Float)->a) - , ifTerm (isTyCon doubleTyCon) (coerceShow$ \(a::Double)->a) - , ifTerm isIntegerTy (coerceShow$ \(a::Integer)->a) - ] - where ifTerm pred f p t@Term{} | pred t = liftM Just (f p t) - ifTerm _ _ _ _ = return Nothing - isIntegerTy Term{ty=ty} = fromMaybe False $ do + [ ifTerm (isTupleTy.ty) (\_p -> liftM (parens . hcat . punctuate comma) + . mapM (y (-1)) + . subTerms) + , ifTerm (\t -> isTyCon listTyCon (ty t) && subTerms t `lengthIs` 2) + (\ p Term{subTerms=[h,t]} -> doList p h t) + , ifTerm (isTyCon intTyCon . ty) (coerceShow$ \(a::Int)->a) + , ifTerm (isTyCon charTyCon . ty) (coerceShow$ \(a::Char)->a) + , ifTerm (isTyCon floatTyCon . ty) (coerceShow$ \(a::Float)->a) + , ifTerm (isTyCon doubleTyCon . ty) (coerceShow$ \(a::Double)->a) + , ifTerm (isIntegerTy . ty) (coerceShow$ \(a::Integer)->a) + ] + where ifTerm pred f prec t@Term{} + | pred t = Just `liftM` f prec t + ifTerm _ _ _ _ = return Nothing + + isIntegerTy ty = fromMaybe False $ do (tc,_) <- splitTyConApp_maybe ty return (tyConName tc == integerTyConName) - isTupleTy Term{ty=ty} = fromMaybe False $ do + + isTupleTy ty = fromMaybe False $ do (tc,_) <- splitTyConApp_maybe ty return (tc `elem` (fst.unzip.elems) boxedTupleArr) - isTyCon a_tc Term{ty=ty} = fromMaybe False $ do + + isTyCon a_tc ty = fromMaybe False $ do (tc,_) <- splitTyConApp_maybe ty return (a_tc == tc) - coerceShow f _ = return . text . show . f . unsafeCoerce# . val + + coerceShow f _p = return . text . show . f . unsafeCoerce# . val + --TODO pprinting of list terms is not lazy doList p h t = do - let elems = h : getListTerms t + let elems = h : getListTerms t isConsLast = termType(last elems) /= termType h print_elems <- mapM (y cons_prec) elems return$ if isConsLast - then cparen (p >= cons_prec) . hsep . punctuate (space<>colon) - $ print_elems - else brackets (hcat$ punctuate comma print_elems) + then cparen (p >= cons_prec) + . fsep + . punctuate (space<>colon) + $ print_elems + else brackets (fsep$ punctuate comma print_elems) where Just a /= Just b = not (a `coreEqType` b) _ /= _ = True getListTerms Term{subTerms=[h,t]} = h : getListTerms t - getListTerms t@Term{subTerms=[]} = [] + getListTerms Term{subTerms=[]} = [] getListTerms t@Suspension{} = [t] getListTerms t = pprPanic "getListTerms" (ppr t) @@ -445,6 +524,9 @@ runTR hsc_env c = do runTR_maybe :: HscEnv -> TR a -> IO (Maybe a) runTR_maybe hsc_env = fmap snd . initTc hsc_env HsSrcFile False iNTERACTIVE +traceTR :: SDoc -> TR () +traceTR = liftTcM . traceTc + trIO :: IO a -> TR a trIO = liftTcM . ioToTcRn @@ -457,8 +539,8 @@ newVar = liftTcM . fmap mkTyVarTy . newFlexiTyVar -- | Returns the instantiated type scheme ty', and the substitution sigma -- such that sigma(ty') = ty instScheme :: Type -> TR (TcType, TvSubst) -instScheme ty | (tvs, rho) <- tcSplitForAllTys ty = liftTcM$ do - (tvs',theta,ty') <- tcInstType (mapM tcInstTyVar) ty +instScheme ty | (tvs, _rho) <- tcSplitForAllTys ty = liftTcM$ do + (tvs',_theta,ty') <- tcInstType (mapM tcInstTyVar) ty return (ty', zipTopTvSubst tvs' (mkTyVarTys tvs)) -- Adds a constraint of the form t1 == t2 @@ -476,17 +558,21 @@ cvObtainTerm :: HscEnv -> Int -> Bool -> Maybe Type -> HValue -> IO Term cvObtainTerm hsc_env bound force mb_ty hval = runTR hsc_env $ do tv <- newVar argTypeKind case mb_ty of - Nothing -> go bound tv tv hval >>= zonkTerm - Just ty | isMonomorphic ty -> go bound ty ty hval >>= zonkTerm + Nothing -> go bound tv tv hval + >>= zonkTerm + >>= return . expandNewtypes + Just ty | isMonomorphic ty -> go bound ty ty hval + >>= zonkTerm + >>= return . expandNewtypes Just ty -> do (ty',rev_subst) <- instScheme (sigmaType ty) addConstraint tv ty' term <- go bound tv tv hval >>= zonkTerm --restore original Tyvars - return$ mapTermType (substTy rev_subst) term + return$ expandNewtypes $ mapTermType (substTy rev_subst) term where go bound _ _ _ | seq bound False = undefined - go 0 tv ty a = do + go 0 tv _ty a = do clos <- trIO $ getClosureData a return (Suspension (tipe clos) (Just tv) a Nothing) go bound tv ty a = do @@ -501,7 +587,7 @@ cvObtainTerm hsc_env bound force mb_ty hval = runTR hsc_env $ do -- and showing the '_' is more useful. t | isThunk t && force -> seq a $ go (pred bound) tv ty a -- We always follow indirections - Indirection _ -> go (pred bound) tv ty $! (ptrs clos ! 0) + Indirection _ -> go bound tv ty $! (ptrs clos ! 0) -- The interesting case Constr -> do Right dcname <- dataConInfoPtrToName (infoPtr clos) @@ -549,7 +635,6 @@ cvObtainTerm hsc_env bound force mb_ty hval = runTR hsc_env $ do tipe_clos -> return (Suspension tipe_clos (Just tv) a Nothing) --- matchSubTypes dc ty | pprTrace "matchSubtypes" (ppr dc <+> ppr ty) False = undefined matchSubTypes dc ty | Just (_,ty_args) <- splitTyConApp_maybe (repType ty) -- assumption: ^^^ looks through newtypes @@ -564,46 +649,59 @@ cvObtainTerm hsc_env bound force mb_ty hval = runTR hsc_env $ do | isPointed ty = ASSERT2(not(null pointed) , ptext SLIT("reOrderTerms") $$ (ppr pointed $$ ppr unpointed)) - head pointed : reOrderTerms (tail pointed) unpointed tys + let (t:tt) = pointed in t : reOrderTerms tt unpointed tys | otherwise = ASSERT2(not(null unpointed) , ptext SLIT("reOrderTerms") $$ (ppr pointed $$ ppr unpointed)) - head unpointed : reOrderTerms pointed (tail unpointed) tys + let (t:tt) = unpointed in t : reOrderTerms pointed tt tys + + expandNewtypes t@Term{ ty=ty, subTerms=tt } + | Just (tc, args) <- splitNewTyConApp_maybe ty + , isNewTyCon tc + , wrapped_type <- newTyConInstRhs tc args + , Just dc <- maybeTyConSingleCon tc + , t' <- expandNewtypes t{ ty = wrapped_type + , subTerms = map expandNewtypes tt } + = NewtypeWrap ty (Right dc) t' + + | otherwise = t{ subTerms = map expandNewtypes tt } + expandNewtypes t = t -- Fast, breadth-first Type reconstruction -max_depth = 10 :: Int -cvReconstructType :: HscEnv -> Bool -> Maybe Type -> HValue -> IO (Maybe Type) -cvReconstructType hsc_env force mb_ty hval = runTR_maybe hsc_env $ do +cvReconstructType :: HscEnv -> Int -> Maybe Type -> HValue -> IO (Maybe Type) +cvReconstructType hsc_env max_depth mb_ty hval = runTR_maybe hsc_env $ do tv <- newVar argTypeKind case mb_ty of Nothing -> do search (isMonomorphic `fmap` zonkTcType tv) - (uncurry go) - [(tv, hval)] + (uncurry go) + (Seq.singleton (tv, hval)) max_depth zonkTcType tv -- TODO untested! Just ty | isMonomorphic ty -> return ty - Just ty -> do - (ty',rev_subst) <- instScheme (sigmaType ty) + Just ty -> do + (ty',rev_subst) <- instScheme (sigmaType ty) addConstraint tv ty' - search (isMonomorphic `fmap` zonkTcType tv) - (\(ty,a) -> go ty a) - [(tv, hval)] + search (isMonomorphic `fmap` zonkTcType tv) + (\(ty,a) -> go ty a) + (Seq.singleton (tv, hval)) max_depth substTy rev_subst `fmap` zonkTcType tv where -- search :: m Bool -> ([a] -> [a] -> [a]) -> [a] -> m () - search stop expand [] depth = return () - search stop expand x 0 = fail$ "Failed to reconstruct a type after " ++ - show max_depth ++ " steps" - search stop expand (x:xx) d = unlessM stop $ do - new <- expand x - search stop expand (xx ++ new) $! (pred d) + search _ _ _ 0 = traceTR (text "Failed to reconstruct a type after " <> + int max_depth <> text " steps") + search stop expand l d = + case viewl l of + EmptyL -> return () + x :< xx -> unlessM stop $ do + new <- expand x + search stop expand (xx `mappend` Seq.fromList new) $! (pred d) -- returns unification tasks,since we are going to want a breadth-first search go :: Type -> HValue -> TR [(Type, HValue)] - go tv a = do + go tv a = do clos <- trIO $ getClosureData a case tipe clos of Indirection _ -> go tv $! (ptrs clos ! 0) @@ -611,44 +709,47 @@ cvReconstructType hsc_env force mb_ty hval = runTR_maybe hsc_env $ do Right dcname <- dataConInfoPtrToName (infoPtr clos) (_,mb_dc) <- tryTcErrs (tcLookupDataCon dcname) case mb_dc of - Nothing-> do + Nothing-> do -- TODO: Check this case - vars <- replicateM (length$ elems$ ptrs clos) - (newVar (liftedTypeKind)) - subTerms <- sequence [ appArr (go tv) (ptrs clos) i - | (i, tv) <- zip [0..] vars] forM [0..length (elems $ ptrs clos)] $ \i -> do - tv <- newVar liftedTypeKind + tv <- newVar liftedTypeKind return$ appArr (\e->(tv,e)) (ptrs clos) i - Just dc -> do - let extra_args = length(dataConRepArgTys dc) - + Just dc -> do + let extra_args = length(dataConRepArgTys dc) - length(dataConOrigArgTys dc) subTtypes <- mapMif (not . isMonomorphic) (\t -> newVar (typeKind t)) (dataConRepArgTys dc) + -- It is vital for newtype reconstruction that the unification step -- is done right here, _before_ the subterms are RTTI reconstructed let myType = mkFunTys subTtypes tv (signatureType,_) <- instScheme(dataConRepType dc) addConstraint myType signatureType return $ [ appArr (\e->(t,e)) (ptrs clos) i - | (i,t) <- drop extra_args $ zip [0..] subTtypes] - otherwise -> return [] + | (i,t) <- drop extra_args $ + zip [0..] (filter isPointed subTtypes)] + _ -> return [] -- This helper computes the difference between a base type t and the -- improved rtti_t computed by RTTI -- The main difference between RTTI types and their normal counterparts -- is that the former are _not_ polymorphic, thus polymorphism must - -- be stripped. Syntactically, forall's must be stripped + -- be stripped. Syntactically, forall's must be stripped. + -- We also remove predicates. +computeRTTIsubst :: Type -> Type -> TvSubst computeRTTIsubst ty rtti_ty = + case mb_subst of + Just subst -> subst + Nothing -> pprPanic "Failed to compute a RTTI substitution" + (ppr (ty, rtti_ty)) -- In addition, we strip newtypes too, since the reconstructed type might -- not have recovered them all - tcUnifyTys (const BindMe) - [repType' $ dropForAlls$ ty] - [repType' $ rtti_ty] --- TODO stripping newtypes shouldn't be necessary, test - + -- TODO stripping newtypes shouldn't be necessary, test + where mb_subst = tcUnifyTys (const BindMe) + [rttiView ty] + [rttiView rtti_ty] -- Dealing with newtypes {- @@ -677,16 +778,18 @@ computeRTTIsubst ty rtti_ty = Note that it is very tricky to make this 'rewriting' work with the unification implemented by TcM, where substitutions are 'inlined'. The order in which - constraints are unified is vital for this (or I am - using TcM wrongly). + constraints are unified is vital for this. + This is a simple form of residuation, the technique of + delaying unification steps until enough information + is available. -} -congruenceNewtypes :: TcType -> TcType -> TcM (TcType,TcType) +congruenceNewtypes :: TcType -> TcType -> TR (TcType,TcType) congruenceNewtypes lhs rhs -- TyVar lhs inductive case | Just tv <- getTyVar_maybe lhs = recoverTc (return (lhs,rhs)) $ do Indirect ty_v <- readMetaTyVar tv - (lhs1, rhs1) <- congruenceNewtypes ty_v rhs + (_lhs1, rhs1) <- congruenceNewtypes ty_v rhs return (lhs, rhs1) -- FunTy inductive case | Just (l1,l2) <- splitFunTy_maybe lhs @@ -695,43 +798,51 @@ congruenceNewtypes lhs rhs (l1',r1') <- congruenceNewtypes l1 r1 return (mkFunTy l1' l2', mkFunTy r1' r2') -- TyconApp Inductive case; this is the interesting bit. - | Just (tycon_l, args_l) <- splitNewTyConApp_maybe lhs - , Just (tycon_r, args_r) <- splitNewTyConApp_maybe rhs + | Just (tycon_l, _) <- splitNewTyConApp_maybe lhs + , Just (tycon_r, _) <- splitNewTyConApp_maybe rhs , tycon_l /= tycon_r - = return (lhs, upgrade tycon_l rhs) + = do rhs' <- upgrade tycon_l rhs + return (lhs, rhs') | otherwise = return (lhs,rhs) - where upgrade :: TyCon -> Type -> Type + where upgrade :: TyCon -> Type -> TR Type upgrade new_tycon ty - | not (isNewTyCon new_tycon) = ty - | ty' <- mkTyConApp new_tycon (map mkTyVarTy $ tyConTyVars new_tycon) - , Just subst <- tcUnifyTys (const BindMe) [ty] [repType ty'] - = substTy subst ty' - -- assumes that reptype doesn't touch tyconApp args ^^^ + | not (isNewTyCon new_tycon) = return ty + | otherwise = do + vars <- mapM (newVar . tyVarKind) (tyConTyVars new_tycon) + let ty' = mkTyConApp new_tycon vars + liftTcM (unifyType ty (repType ty')) + -- assumes that reptype doesn't ^^^^ touch tyconApp args + return ty' -------------------------------------------------------------------------------- -- Semantically different to recoverM in TcRnMonad -- recoverM retains the errors in the first action, -- whereas recoverTc here does not +recoverTc :: TcM a -> TcM a -> TcM a recoverTc recover thing = do (_,mb_res) <- tryTcErrs thing case mb_res of Nothing -> recover Just res -> return res +isMonomorphic :: Type -> Bool isMonomorphic ty | (tvs, ty') <- splitForAllTys ty = null tvs && (isEmptyVarSet . tyVarsOfType) ty' mapMif :: Monad m => (a -> Bool) -> (a -> m a) -> [a] -> m [a] mapMif pred f xx = sequence $ mapMif_ pred f xx -mapMif_ pred f [] = [] -mapMif_ pred f (x:xx) = (if pred x then f x else return x) : mapMif_ pred f xx + where + mapMif_ _ _ [] = [] + mapMif_ pred f (x:xx) = (if pred x then f x else return x) : mapMif_ pred f xx +unlessM :: Monad m => m Bool -> m () -> m () unlessM condM acc = condM >>= \c -> unless c acc -- Strict application of f at index i +appArr :: Ix i => (e -> a) -> Array i e -> Int -> a appArr f a@(Array _ _ _ ptrs#) i@(I# i#) = ASSERT (i < length(elems a)) case indexArray# ptrs# i# of @@ -743,11 +854,14 @@ zonkTerm = foldTerm idTermFoldM { zonkTcType ty >>= \ty' -> return (Term ty' dc v tt) ,fSuspension = \ct ty v b -> fmapMMaybe zonkTcType ty >>= \ty -> - return (Suspension ct ty v b)} + return (Suspension ct ty v b) + ,fNewtypeWrap= \ty dc t -> + return NewtypeWrap `ap` zonkTcType ty `ap` return dc `ap` t} -- Is this defined elsewhere? -- Generalize the type: find all free tyvars and wrap in the appropiate ForAll. +sigmaType :: Type -> Type sigmaType ty = mkForAllTys (varSetElems$ tyVarsOfType (dropForAlls ty)) ty