X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2Fghci%2FRtClosureInspect.hs;h=e2a4f8e6088882806ac9d7b456530e181c552a69;hp=2cbdbe82f4517cdc54dcd7111862fe0923f07717;hb=7fc749a43b4b6b85d234fa95d4928648259584f4;hpb=955789f4fdc14d77063703d9d174353e6d9425a2 diff --git a/compiler/ghci/RtClosureInspect.hs b/compiler/ghci/RtClosureInspect.hs index 2cbdbe8..e2a4f8e 100644 --- a/compiler/ghci/RtClosureInspect.hs +++ b/compiler/ghci/RtClosureInspect.hs @@ -6,11 +6,21 @@ -- ----------------------------------------------------------------------------- +{-# OPTIONS -w #-} +-- The above warning supression flag is a temporary kludge. +-- While working on this module you are encouraged to remove it and fix +-- any warnings in the module. See +-- http://hackage.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#Warnings +-- for details + module RtClosureInspect( - cvObtainTerm, -- :: HscEnv -> Bool -> Maybe Type -> HValue -> IO Term + cvObtainTerm, -- :: HscEnv -> Int -> Bool -> Maybe Type -> HValue -> IO Term Term(..), + isTerm, + isSuspension, + isPrim, pprTerm, cPprTerm, cPprTermBase, @@ -25,30 +35,38 @@ module RtClosureInspect( mapTermType, termTyVars, -- unsafeDeepSeq, - cvReconstructType + cvReconstructType, + computeRTTIsubst, + sigmaType, + Closure(..), + getClosureData, + ClosureType(..), + isConstr, + isIndirection ) where #include "HsVersions.h" import ByteCodeItbls ( StgInfoTable ) import qualified ByteCodeItbls as BCI( StgInfoTable(..) ) -import ByteCodeLink ( HValue ) import HscTypes ( HscEnv ) +import Linker import DataCon import Type -import TcRnMonad ( TcM, initTcPrintErrors, ioToTcRn, recoverM, writeMutVar ) +import TcRnMonad ( TcM, initTc, ioToTcRn, + tryTcErrs) import TcType import TcMType import TcUnify import TcGadt +import TcEnv +import DriverPhases import TyCon -import Var import Name import VarEnv -import OccName +import Util import VarSet -import {-#SOURCE#-} TcRnDriver ( tcRnRecoverDataCon ) import TysPrim import PrelNames @@ -58,17 +76,19 @@ import Constants import Outputable import Maybes import Panic -import FiniteMap import GHC.Arr ( Array(..) ) -import GHC.Ptr ( Ptr(..), castPtr ) import GHC.Exts import Control.Monad import Data.Maybe import Data.Array.Base -import Data.List ( partition, nub ) +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 --------------------------------------------- -- * A representation of semi evaluated Terms @@ -86,7 +106,11 @@ import Foreign -} data Term = Term { ty :: Type - , dc :: DataCon + , 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 , subTerms :: [Term] } @@ -99,6 +123,7 @@ data Term = Term { ty :: Type , bound_to :: Maybe Name -- Useful for printing } +isTerm, isSuspension, isPrim :: Term -> Bool isTerm Term{} = True isTerm _ = False isSuspension Suspension{} = True @@ -106,6 +131,7 @@ isSuspension _ = False isPrim Prim{} = True isPrim _ = False +termType :: Term -> Maybe Type termType t@(Suspension {}) = mb_ty t termType t = Just$ ty t @@ -154,11 +180,13 @@ getClosureData a = (# iptr, ptrs, nptrs #) -> do itbl <- peek (Ptr iptr) let tipe = readCType (BCI.tipe itbl) - elems = BCI.ptrs itbl - ptrsList = Array 0 (fromIntegral$ elems) ptrs + 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)] ] - ptrsList `seq` return (Closure tipe (Ptr iptr) itbl ptrsList nptrs_data) + ASSERT(fromIntegral elems >= 0) return () + ptrsList `seq` + return (Closure tipe (Ptr iptr) itbl ptrsList nptrs_data) readCType :: Integral a => a -> ClosureType readCType i @@ -173,7 +201,7 @@ readCType i | fromIntegral i == pAP_CODE = PAP | otherwise = Other (fromIntegral i) -isConstr, isIndirection :: ClosureType -> Bool +isConstr, isIndirection, isThunk :: ClosureType -> Bool isConstr Constr = True isConstr _ = False @@ -195,16 +223,16 @@ isFullyEvaluated a = do otherwise -> return False where amapM f = sequence . amap' f -amap' f (Array i0 i arr#) = map (\(I# i#) -> case indexArray# arr# i# of - (# e #) -> f e) - [0 .. i - i0] +amap' f (Array i0 i _ arr#) = map g [0 .. i - i0] + where g (I# i#) = case indexArray# arr# i# of + (# e #) -> f e -- TODO: Fix it. Probably the otherwise case is failing, trace/debug it {- unsafeDeepSeq :: a -> b -> b unsafeDeepSeq = unsafeDeepSeq1 2 where unsafeDeepSeq1 0 a b = seq a $! b - unsafeDeepSeq1 i a b -- 1st case avoids infinite loops for non reducible thunks + unsafeDeepSeq1 i a b -- 1st case avoids infinite loops for non reducible thunks | not (isConstr tipe) = seq a $! unsafeDeepSeq1 (i-1) a b -- | unsafePerformIO (isFullyEvaluated a) = b | otherwise = case unsafePerformIO (getClosureData a) of @@ -212,7 +240,8 @@ unsafeDeepSeq = unsafeDeepSeq1 2 where tipe = unsafePerformIO (getClosureType a) -} isPointed :: Type -> Bool -isPointed t | Just (t, _) <- splitTyConApp_maybe t = not$ isUnliftedTypeKind (tyConKind t) +isPointed t | Just (t, _) <- splitTyConApp_maybe t + = not$ isUnliftedTypeKind (tyConKind t) isPointed _ = True extractUnboxed :: [Type] -> Closure -> [[Word]] @@ -223,7 +252,7 @@ extractUnboxed tt clos = go tt (nonPtrs clos) | otherwise = pprPanic "Expected a TcTyCon" (ppr t) go [] _ = [] go (t:tt) xx - | (x, rest) <- splitAt (sizeofType t `div` wORD_SIZE) xx + | (x, rest) <- splitAt ((sizeofType t + wORD_SIZE - 1) `div` wORD_SIZE) xx = x : go tt rest sizeofTyCon = sizeofPrimRep . tyConPrimRep @@ -232,9 +261,10 @@ sizeofTyCon = sizeofPrimRep . tyConPrimRep -- * Traversals for Terms ----------------------------------- -data TermFold a = TermFold { fTerm :: Type -> DataCon -> HValue -> [a] -> a +data TermFold a = TermFold { fTerm :: Type -> Either String DataCon -> HValue -> [a] -> a , fPrim :: Type -> [Word] -> a - , fSuspension :: ClosureType -> Maybe Type -> HValue -> Maybe Name -> a + , fSuspension :: ClosureType -> Maybe Type -> HValue + -> Maybe Name -> a } foldTerm :: TermFold a -> Term -> a @@ -255,11 +285,13 @@ idTermFoldM = TermFold { fSuspension = (((return.).).). Suspension } +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 } +termTyVars :: Term -> TyVarSet termTyVars = foldTerm TermFold { fTerm = \ty _ _ tt -> tyVarsOfType ty `plusVarEnv` concatVarEnv tt, @@ -271,73 +303,89 @@ termTyVars = foldTerm TermFold { -- Pretty printing of terms ---------------------------------- -app_prec::Int +app_prec,cons_prec ::Int app_prec = 10 +cons_prec = 5 -- TODO Extract this info from GHC itself + +pprTerm y p t | Just doc <- pprTermM y p t = doc -pprTerm :: Int -> Term -> SDoc -pprTerm p Term{dc=dc, subTerms=tt} -{- | dataConIsInfix dc, (t1:t2:tt') <- tt +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 + tt_docs <- mapM (y app_prec) tt + return$ cparen (not(null tt) && p >= app_prec) (text dc_tag <+> sep tt_docs) + +pprTermM y p t@Term{dc=Right dc, subTerms=tt, ty=ty} +{- | dataConIsInfix dc, (t1:t2:tt') <- tt --TODO fixity = parens (pprTerm1 True t1 <+> ppr dc <+> pprTerm1 True ppr t2) <+> hsep (map (pprTerm1 True) tt) --} - | null tt = ppr dc - | otherwise = cparen (p >= app_prec) - (ppr dc <+> sep (map (pprTerm app_prec) tt)) - - where fixity = undefined - -pprTerm _ t = pprTerm1 t - -pprTerm1 Prim{value=words, ty=ty} = text$ repPrim (tyConAppTyCon ty) words -pprTerm1 t@Term{} = pprTerm 0 t -pprTerm1 Suspension{bound_to=Nothing} = char '_' -- <> ppr ct <> char '_' -pprTerm1 Suspension{mb_ty=Just ty, bound_to=Just n} - | Just _ <- splitFunTy_maybe ty = ptext SLIT("") - | otherwise = parens$ ppr n <> text "::" <> ppr ty - - -cPprTerm :: forall m. Monad m => ((Int->Term->m SDoc)->[Int->Term->m (Maybe SDoc)]) -> Term -> m SDoc +-} -- 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) + +pprTermM y _ t = pprTermM1 y t +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} + | Just _ <- splitFunTy_maybe ty = return$ ptext SLIT("") + | otherwise = return$ parens$ ppr n <> text "::" <> ppr ty + +-- 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{subTerms=tt, dc=dc} = do - let mb_customDocs = map (($t) . ($prec)) (custom go) :: [m (Maybe SDoc)] - first_success <- firstJustM mb_customDocs - case first_success of - Just doc -> return$ cparen (prec>app_prec+1) doc --- | dataConIsInfix dc, (t1:t2:tt') <- tt = - Nothing -> do pprSubterms <- mapM (go (app_prec+1)) tt - return$ cparen (prec >= app_prec) - (ppr dc <+> sep pprSubterms) - go _ t = return$ pprTerm1 t + go prec t@Term{} = do + let default_ prec t = Just `liftM` pprTermM go prec t + mb_customDocs = [pp prec t | pp <- custom go ++ [default_]] + Just doc <- firstJustM mb_customDocs + return$ cparen (prec>app_prec+1) doc + go _ t = pprTermM1 go 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 pprP = +cPprTermBase y = [ - ifTerm isTupleDC (\_ -> liftM (parens . hcat . punctuate comma) - . mapM (pprP (-1)) . subTerms) - , ifTerm (isDC consDataCon) (\ p Term{subTerms=[h,t]} -> doList p h t) - , ifTerm (isDC intDataCon) (coerceShow$ \(a::Int)->a) - , ifTerm (isDC charDataCon) (coerceShow$ \(a::Char)->a) --- , ifTerm (isDC wordDataCon) (coerceShow$ \(a::Word)->a) - , ifTerm (isDC floatDataCon) (coerceShow$ \(a::Float)->a) - , ifTerm (isDC doubleDataCon) (coerceShow$ \(a::Double)->a) - , ifTerm isIntegerDC (coerceShow$ \(a::Integer)->a) + 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 = if pred t then liftM Just (f p t) else return Nothing - isIntegerDC Term{dc=dc} = - dataConName dc `elem` [ smallIntegerDataConName - , largeIntegerDataConName] - isTupleDC Term{dc=dc} = dc `elem` snd (unzip (elems boxedTupleArr)) - isDC a_dc Term{dc=dc} = a_dc == dc + where ifTerm pred f p t@Term{} | pred t = liftM Just (f p t) + ifTerm _ _ _ _ = return Nothing + isIntegerTy Term{ty=ty} = fromMaybe False $ do + (tc,_) <- splitTyConApp_maybe ty + return (tyConName tc == integerTyConName) + isTupleTy Term{ty=ty} = fromMaybe False $ do + (tc,_) <- splitTyConApp_maybe ty + return (tc `elem` (fst.unzip.elems) boxedTupleArr) + isTyCon a_tc Term{ty=ty} = fromMaybe False $ do + (tc,_) <- splitTyConApp_maybe ty + return (a_tc == tc) coerceShow f _ = return . text . show . f . unsafeCoerce# . val --TODO pprinting of list terms is not lazy doList p h t = do let elems = h : getListTerms t isConsLast = termType(last elems) /= termType h - print_elems <- mapM (pprP 5) elems + print_elems <- mapM (y cons_prec) elems return$ if isConsLast - then cparen (p >= 5) . hsep . punctuate (space<>colon) + then cparen (p >= cons_prec) . hsep . punctuate (space<>colon) $ print_elems else brackets (hcat$ punctuate comma print_elems) @@ -348,6 +396,7 @@ cPprTermBase pprP = getListTerms t@Suspension{} = [t] getListTerms t = pprPanic "getListTerms" (ppr t) + repPrim :: TyCon -> [Word] -> String repPrim t = rep where rep x @@ -376,6 +425,8 @@ repPrim t = rep where | t == tVarPrimTyCon = "" | otherwise = showSDoc (char '<' <> ppr t <> char '>') where build ww = unsafePerformIO $ withArray ww (peek . castPtr) +-- This ^^^ relies on the representation of Haskell heap values being +-- the same as in a C array. ----------------------------------- -- Type Reconstruction @@ -403,18 +454,22 @@ type TR a = TcM a runTR :: HscEnv -> TR a -> IO a runTR hsc_env c = do - mb_term <- initTcPrintErrors hsc_env iNTERACTIVE c + mb_term <- runTR_maybe hsc_env c case mb_term of Nothing -> panic "Can't unify" - Just x -> return x + Just x -> return x + +runTR_maybe :: HscEnv -> TR a -> IO (Maybe a) +runTR_maybe hsc_env = fmap snd . initTc hsc_env HsSrcFile False iNTERACTIVE trIO :: IO a -> TR a trIO = liftTcM . ioToTcRn +liftTcM :: TcM a -> TR a liftTcM = id -newVar :: Kind -> TR TcTyVar -newVar = liftTcM . newFlexiTyVar +newVar :: Kind -> TR TcType +newVar = liftTcM . fmap mkTyVarTy . newFlexiTyVar -- | Returns the instantiated type scheme ty', and the substitution sigma -- such that sigma(ty') = ty @@ -423,70 +478,100 @@ 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 +-- t1 is expected to come from walking the heap +-- t2 is expected to come from a datacon signature +-- Before unification, congruenceNewtypes needs to +-- do its magic. addConstraint :: TcType -> TcType -> TR () addConstraint t1 t2 = congruenceNewtypes t1 t2 >>= uncurry unifyType - - + >> return () -- TOMDO: what about the coercion? + -- we should consider family instances -- Type & Term reconstruction -cvObtainTerm :: HscEnv -> Bool -> Maybe Type -> HValue -> IO Term -cvObtainTerm hsc_env force mb_ty hval = runTR hsc_env $ do - tv <- liftM mkTyVarTy (newVar argTypeKind) +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 tv tv hval >>= zonkTerm - Just ty | isMonomorphic ty -> go ty ty hval >>= zonkTerm + Nothing -> go bound tv tv hval >>= zonkTerm + Just ty | isMonomorphic ty -> go bound ty ty hval >>= zonkTerm Just ty -> do (ty',rev_subst) <- instScheme (sigmaType ty) addConstraint tv ty' - term <- go tv tv hval >>= zonkTerm + term <- go bound tv tv hval >>= zonkTerm --restore original Tyvars return$ mapTermType (substTy rev_subst) term where - go tv ty a = do - let monomorphic = not(isTyVarTy tv) -- This is a convention. The ancestor tests for - -- monomorphism and passes a type instead of a tv + go bound _ _ _ | seq bound False = undefined + go 0 tv ty a = do + clos <- trIO $ getClosureData a + return (Suspension (tipe clos) (Just tv) a Nothing) + go bound tv ty a = do + let monomorphic = not(isTyVarTy tv) + -- This ^^^ is a convention. The ancestor tests for + -- monomorphism and passes a type instead of a tv clos <- trIO $ getClosureData a case tipe clos of -- Thunks we may want to force -- NB. this won't attempt to force a BLACKHOLE. Even with :force, we never -- force blackholes, because it would almost certainly result in deadlock, -- and showing the '_' is more useful. - t | isThunk t && force -> seq a $ go tv ty a + t | isThunk t && force -> seq a $ go (pred bound) tv ty a -- We always follow indirections - Indirection _ -> go tv ty $! (ptrs clos ! 0) + Indirection _ -> go (pred bound) tv ty $! (ptrs clos ! 0) -- The interesting case Constr -> do - m_dc <- trIO$ tcRnRecoverDataCon hsc_env (infoPtr clos) - case m_dc of - Nothing -> panic "Can't find the DataCon for a term" + Right dcname <- dataConInfoPtrToName (infoPtr clos) + (_,mb_dc) <- tryTcErrs (tcLookupDataCon dcname) + case mb_dc of + Nothing -> do -- This can happen for private constructors compiled -O0 + -- where the .hi descriptor does not export them + -- In such case, we return a best approximation: + -- ignore the unpointed args, and recover the pointeds + -- This preserves laziness, and should be safe. + let tag = showSDoc (ppr dcname) + vars <- replicateM (length$ elems$ ptrs clos) + (newVar (liftedTypeKind)) + subTerms <- sequence [appArr (go (pred bound) tv tv) (ptrs clos) i + | (i, tv) <- zip [0..] vars] + return (Term tv (Left ('<' : tag ++ ">")) a subTerms) Just dc -> do - let extra_args = length(dataConRepArgTys dc) - length(dataConOrigArgTys dc) + let extra_args = length(dataConRepArgTys dc) - + length(dataConOrigArgTys dc) subTtypes = matchSubTypes dc ty (subTtypesP, subTtypesNP) = partition isPointed subTtypes subTermTvs <- sequence - [ if isMonomorphic t then return t else (mkTyVarTy `fmap` newVar k) + [ if isMonomorphic t then return t + else (newVar k) | (t,k) <- zip subTtypesP (map typeKind subTtypesP)] - -- It is vital for newtype reconstruction that the unification step is done - -- right here, _before_ the subterms are RTTI reconstructed. + -- It is vital for newtype reconstruction that the unification step + -- is done right here, _before_ the subterms are RTTI reconstructed when (not monomorphic) $ do - let myType = mkFunTys (reOrderTerms subTermTvs subTtypesNP subTtypes) tv - instScheme(dataConRepType dc) >>= addConstraint myType . fst - subTermsP <- sequence $ drop extra_args -- all extra arguments are pointed - [ appArr (go tv t) (ptrs clos) i + let myType = mkFunTys (reOrderTerms subTermTvs + subTtypesNP + subTtypes) + tv + (signatureType,_) <- instScheme(dataConRepType dc) + addConstraint myType signatureType + subTermsP <- sequence $ drop extra_args + -- ^^^ all extra arguments are pointed + [ appArr (go (pred bound) tv t) (ptrs clos) i | (i,tv,t) <- zip3 [0..] subTermTvs subTtypesP] let unboxeds = extractUnboxed subTtypesNP clos subTermsNP = map (uncurry Prim) (zip subTtypesNP unboxeds) - subTerms = reOrderTerms subTermsP subTermsNP (drop extra_args subTtypes) - return (Term tv dc a subTerms) + subTerms = reOrderTerms subTermsP subTermsNP + (drop extra_args subTtypes) + return (Term tv (Right dc) a subTerms) -- The otherwise case: can be a Thunk,AP,PAP,etc. - otherwise -> - return (Suspension (tipe clos) (Just tv) a Nothing) + 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) - , null (dataConExTyVars dc) --TODO Handle the case of extra existential tyvars +-- assumption: ^^^ looks through newtypes + , isVanillaDataCon dc --TODO non-vanilla case = dataConInstArgTys dc ty_args - | otherwise = dataConRepArgTys dc -- This is used to put together pointed and nonpointed subterms in the @@ -494,59 +579,95 @@ cvObtainTerm hsc_env force mb_ty hval = runTR hsc_env $ do reOrderTerms _ _ [] = [] reOrderTerms pointed unpointed (ty:tys) | isPointed ty = ASSERT2(not(null pointed) - , ptext SLIT("reOrderTerms") $$ (ppr pointed $$ ppr unpointed)) + , ptext SLIT("reOrderTerms") $$ + (ppr pointed $$ ppr unpointed)) head pointed : reOrderTerms (tail pointed) unpointed tys | otherwise = ASSERT2(not(null unpointed) - , ptext SLIT("reOrderTerms") $$ (ppr pointed $$ ppr unpointed)) + , ptext SLIT("reOrderTerms") $$ + (ppr pointed $$ ppr unpointed)) head unpointed : reOrderTerms pointed (tail unpointed) tys --- Fast, breadth-first version of obtainTerm that deals only with type reconstruction - -cvReconstructType :: HscEnv -> Bool -> Maybe Type -> HValue -> IO Type -cvReconstructType hsc_env force mb_ty hval = runTR hsc_env $ do - tv <- liftM mkTyVarTy (newVar argTypeKind) +-- 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 + tv <- newVar argTypeKind case mb_ty of - Nothing -> search (isMonomorphic `fmap` zonkTcType tv) (++) [(tv, hval)] >> - zonkTcType tv -- TODO untested! + Nothing -> do search (isMonomorphic `fmap` zonkTcType tv) + (uncurry go) + (Seq.singleton (tv, hval)) + max_depth + zonkTcType tv -- TODO untested! Just ty | isMonomorphic ty -> return ty - Just ty -> do + Just ty -> do (ty',rev_subst) <- instScheme (sigmaType ty) addConstraint tv ty' - search (isMonomorphic `fmap` zonkTcType tv) (++) [(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 combine [] = return () - search stop combine ((t,a):jj) = (jj `combine`) `fmap` go t a >>= - unlessM stop . search stop combine - - -- returns unification tasks, since we are going to want a breadth-first search + search stop expand l depth | Seq.null l = return () + search stop expand x 0 = fail$ "Failed to reconstruct a type after " ++ + show max_depth ++ " steps" + search stop expand l d | x :< xx <- viewl l = 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 $! (ptrs clos ! 0) Constr -> do - m_dc <- trIO$ tcRnRecoverDataCon hsc_env (infoPtr clos) - case m_dc of - Nothing -> panic "Can't find the DataCon for a term" - Just dc -> do - let extra_args = length(dataConRepArgTys dc) - length(dataConOrigArgTys dc) + Right dcname <- dataConInfoPtrToName (infoPtr clos) + (_,mb_dc) <- tryTcErrs (tcLookupDataCon dcname) + case mb_dc of + 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 + return$ appArr (\e->(tv,e)) (ptrs clos) i + + Just dc -> do + let extra_args = length(dataConRepArgTys dc) - + length(dataConOrigArgTys dc) subTtypes <- mapMif (not . isMonomorphic) - (\t -> mkTyVarTy `fmap` newVar (typeKind t)) + (\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 - fst `fmap` instScheme(dataConRepType dc) >>= addConstraint myType - return $map (\(I# i#,t) -> case ptrs clos of - (Array _ _ ptrs#) -> case indexArray# ptrs# i# of - (# e #) -> (t,e)) - (drop extra_args $ zip [0..] subTtypes) + + -- 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..] (filter isPointed subTtypes)] otherwise -> 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 +computeRTTIsubst 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 + -- Dealing with newtypes {- @@ -579,52 +700,45 @@ cvReconstructType hsc_env force mb_ty hval = runTR hsc_env $ do using TcM wrongly). -} congruenceNewtypes :: TcType -> TcType -> TcM (TcType,TcType) -congruenceNewtypes = go True - where - go rewriteRHS lhs rhs +congruenceNewtypes lhs rhs -- TyVar lhs inductive case | Just tv <- getTyVar_maybe lhs - = recoverM (return (lhs,rhs)) $ do - Indirect ty_v <- readMetaTyVar tv - (lhs', rhs') <- go rewriteRHS ty_v rhs - writeMutVar (metaTvRef tv) (Indirect lhs') - return (lhs, rhs') - -- TyVar rhs inductive case - | Just tv <- getTyVar_maybe rhs - = recoverM (return (lhs,rhs)) $ do + = recoverTc (return (lhs,rhs)) $ do Indirect ty_v <- readMetaTyVar tv - (lhs', rhs') <- go rewriteRHS lhs ty_v - writeMutVar (metaTvRef tv) (Indirect rhs') - return (lhs', rhs) + (lhs1, rhs1) <- congruenceNewtypes ty_v rhs + return (lhs, rhs1) -- FunTy inductive case | Just (l1,l2) <- splitFunTy_maybe lhs , Just (r1,r2) <- splitFunTy_maybe rhs - = do (l2',r2') <- go True l2 r2 - (l1',r1') <- go False l1 r1 + = do (l2',r2') <- congruenceNewtypes l2 r2 + (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 = do - - let (tycon_l',args_l') = if isNewTyCon tycon_r && not(isNewTyCon tycon_l) - then (tycon_r, rewrite tycon_r lhs) - else (tycon_l, args_l) - (tycon_r',args_r') = if rewriteRHS && isNewTyCon tycon_l && not(isNewTyCon tycon_r) - then (tycon_l, rewrite tycon_l rhs) - else (tycon_r, args_r) - (args_l'', args_r'') <- unzip `liftM` zipWithM (go rewriteRHS) args_l' args_r' - return (mkTyConApp tycon_l' args_l'', mkTyConApp tycon_r' args_r'') + , Just (tycon_r, args_r) <- splitNewTyConApp_maybe rhs + , tycon_l /= tycon_r + = return (lhs, upgrade tycon_l rhs) | otherwise = return (lhs,rhs) - where rewrite newtyped_tc lame_tipe - | (tvs, tipe) <- newTyConRep newtyped_tc - = case tcUnifyTys (const BindMe) [tipe] [lame_tipe] of - Just subst -> substTys subst (map mkTyVarTy tvs) - otherwise -> panic "congruenceNewtypes: Can't unify a newtype" - - ------------------------------------------------------------------------------------- + where upgrade :: TyCon -> Type -> 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 ^^^ + + +-------------------------------------------------------------------------------- +-- Semantically different to recoverM in TcRnMonad +-- recoverM retains the errors in the first action, +-- whereas recoverTc here does not +recoverTc recover thing = do + (_,mb_res) <- tryTcErrs thing + case mb_res of + Nothing -> recover + Just res -> return res isMonomorphic ty | (tvs, ty') <- splitForAllTys ty = null tvs && (isEmptyVarSet . tyVarsOfType) ty' @@ -637,8 +751,10 @@ mapMif_ pred f (x:xx) = (if pred x then f x else return x) : mapMif_ pred f xx unlessM condM acc = condM >>= \c -> unless c acc -- Strict application of f at index i -appArr f (Array _ _ ptrs#) (I# i#) = case indexArray# ptrs# i# of - (# e #) -> f e +appArr f a@(Array _ _ _ ptrs#) i@(I# i#) + = ASSERT (i < length(elems a)) + case indexArray# ptrs# i# of + (# e #) -> f e zonkTerm :: Term -> TcM Term zonkTerm = foldTerm idTermFoldM {