X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Fghci%2FRtClosureInspect.hs;h=bc6cc4724bab6e654b73133f6fd923689fb43e4c;hb=ece94e430901c3480e842dcdbbcbef2f1bc070f7;hp=d4475a7463d2b082694ca98384d27e413ab17875;hpb=de73aab4cab85f9b28afdf00c0174591e7070160;p=ghc-hetmet.git diff --git a/compiler/ghci/RtClosureInspect.hs b/compiler/ghci/RtClosureInspect.hs index d4475a7..bc6cc47 100644 --- a/compiler/ghci/RtClosureInspect.hs +++ b/compiler/ghci/RtClosureInspect.hs @@ -22,7 +22,10 @@ module RtClosureInspect( isFullyEvaluated, isPointed, isFullyEvaluatedTerm, + mapTermType, + termTyVars, -- unsafeDeepSeq, + cvReconstructType ) where #include "HsVersions.h" @@ -34,7 +37,8 @@ import HscTypes ( HscEnv ) import DataCon import Type -import TcRnMonad ( TcM, initTcPrintErrors, ioToTcRn, recoverM, writeMutVar ) +import TcRnMonad ( TcM, initTcPrintErrors, ioToTcRn, recoverM + , writeMutVar ) import TcType import TcMType import TcUnify @@ -51,7 +55,7 @@ import TysPrim import PrelNames import TysWiredIn -import Constants ( wORD_SIZE ) +import Constants import Outputable import Maybes import Panic @@ -59,17 +63,14 @@ import FiniteMap import GHC.Arr ( Array(..) ) import GHC.Ptr ( Ptr(..), castPtr ) -import GHC.Exts -import GHC.Int ( Int32(..), Int64(..) ) -import GHC.Word ( Word32(..), Word64(..) ) +import GHC.Exts import Control.Monad import Data.Maybe import Data.Array.Base -import Data.List ( partition ) -import Foreign.Storable - -import IO +import Data.List ( partition, nub ) +import Foreign +import System.IO.Unsafe --------------------------------------------- -- * A representation of semi evaluated Terms @@ -92,7 +93,7 @@ data Term = Term { ty :: Type , subTerms :: [Term] } | Prim { ty :: Type - , value :: String } + , value :: [Word] } | Suspension { ctype :: ClosureType , mb_ty :: Maybe Type @@ -136,7 +137,7 @@ data Closure = Closure { tipe :: ClosureType , infoPtr :: Ptr () , infoTable :: StgInfoTable , ptrs :: Array Int HValue - , nonPtrs :: ByteArray# + , nonPtrs :: [Word] } instance Outputable ClosureType where @@ -157,7 +158,10 @@ getClosureData a = let tipe = readCType (BCI.tipe itbl) elems = BCI.ptrs itbl ptrsList = Array 0 (fromIntegral$ elems) ptrs - ptrsList `seq` return (Closure tipe (Ptr iptr) itbl ptrsList nptrs) + nptrs_data = [W# (indexWordArray# nptrs i) + | I# i <- [0.. fromIntegral (BCI.nptrs itbl)] ] + ptrsList `seq` + return (Closure tipe (Ptr iptr) itbl ptrsList nptrs_data) readCType :: Integral a => a -> ClosureType readCType i @@ -203,7 +207,7 @@ amap' f (Array i0 i arr#) = map (\(I# i#) -> case indexArray# arr# i# of 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 $! unsafeDeepSeq1 (i-1) a b -- | unsafePerformIO (isFullyEvaluated a) = b | otherwise = case unsafePerformIO (getClosureData a) of @@ -211,59 +215,31 @@ unsafeDeepSeq = unsafeDeepSeq1 2 where tipe = unsafePerformIO (getClosureType a) -} isPointed :: Type -> Bool -isPointed t | Just (t, _) <- splitTyConApp_maybe t = not$ isUnliftedTypeKind (tyConKind t) +isPointed t | Just (t, _) <- splitTyConApp_maybe t + = not$ isUnliftedTypeKind (tyConKind t) isPointed _ = True -#define MKDECODER(offset,cons,builder) (offset, show$ cons (builder addr 0#)) - -extractUnboxed :: [Type] -> ByteArray# -> [String] -extractUnboxed tt ba = helper tt (byteArrayContents# ba) - where helper :: [Type] -> Addr# -> [String] - helper (t:tt) addr - | Just ( tycon,_) <- splitTyConApp_maybe t - = let (offset, txt) = decode tycon addr - (I# word_offset) = offset*wORD_SIZE - in txt : helper tt (plusAddr# addr word_offset) - | otherwise - = -- ["extractUnboxed.helper: Urk. I got a " ++ showSDoc (ppr t)] - panic$ "extractUnboxed.helper: Urk. I got a " ++ showSDoc (ppr t) - helper [] addr = [] - decode :: TyCon -> Addr# -> (Int, String) - decode t addr - | t == charPrimTyCon = MKDECODER(1,C#,indexCharOffAddr#) - | t == intPrimTyCon = MKDECODER(1,I#,indexIntOffAddr#) - | t == wordPrimTyCon = MKDECODER(1,W#,indexWordOffAddr#) - | t == floatPrimTyCon = MKDECODER(1,F#,indexFloatOffAddr#) - | t == doublePrimTyCon = MKDECODER(2,D#,indexDoubleOffAddr#) - | t == int32PrimTyCon = MKDECODER(1,I32#,indexInt32OffAddr#) - | t == word32PrimTyCon = MKDECODER(1,W32#,indexWord32OffAddr#) - | t == int64PrimTyCon = MKDECODER(2,I64#,indexInt64OffAddr#) - | t == word64PrimTyCon = MKDECODER(2,W64#,indexWord64OffAddr#) - | t == addrPrimTyCon = MKDECODER(1,I#,(\x off-> addr2Int# (indexAddrOffAddr# x off))) --OPT Improve the presentation of addresses - | t == stablePtrPrimTyCon = (1, "") - | t == stableNamePrimTyCon = (1, "") - | t == statePrimTyCon = (1, "") - | t == realWorldTyCon = (1, "") - | t == threadIdPrimTyCon = (1, "") - | t == weakPrimTyCon = (1, "") - | t == arrayPrimTyCon = (1,"") - | t == byteArrayPrimTyCon = (1,"") - | t == mutableArrayPrimTyCon = (1, "") - | t == mutableByteArrayPrimTyCon = (1, "") - | t == mutVarPrimTyCon= (1, "") - | t == mVarPrimTyCon = (1, "") - | t == tVarPrimTyCon = (1, "") - | otherwise = (1, showSDoc (char '<' <> ppr t <> char '>')) - -- We cannot know the right offset in the otherwise case, so 1 is just a wild dangerous guess! - -- TODO: Improve the offset handling in decode (make it machine dependant) +extractUnboxed :: [Type] -> Closure -> [[Word]] +extractUnboxed tt clos = go tt (nonPtrs clos) + where sizeofType t + | Just (tycon,_) <- splitTyConApp_maybe t + = ASSERT (isPrimTyCon tycon) sizeofTyCon tycon + | otherwise = pprPanic "Expected a TcTyCon" (ppr t) + go [] _ = [] + go (t:tt) xx + | (x, rest) <- splitAt (sizeofType t `div` wORD_SIZE) xx + = x : go tt rest + +sizeofTyCon = sizeofPrimRep . tyConPrimRep ----------------------------------- -- * Traversals for Terms ----------------------------------- data TermFold a = TermFold { fTerm :: Type -> DataCon -> HValue -> [a] -> a - , fPrim :: Type -> String -> a - , fSuspension :: ClosureType -> Maybe Type -> HValue -> Maybe Name -> a + , fPrim :: Type -> [Word] -> a + , fSuspension :: ClosureType -> Maybe Type -> HValue + -> Maybe Name -> a } foldTerm :: TermFold a -> Term -> a @@ -284,6 +260,18 @@ idTermFoldM = TermFold { fSuspension = (((return.).).). Suspension } +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 = foldTerm TermFold { + fTerm = \ty _ _ tt -> + tyVarsOfType ty `plusVarEnv` concatVarEnv tt, + fSuspension = \_ mb_ty _ _ -> + maybe emptyVarEnv tyVarsOfType mb_ty, + fPrim = \ _ _ -> emptyVarEnv } + where concatVarEnv = foldr plusVarEnv emptyVarEnv ---------------------------------- -- Pretty printing of terms ---------------------------------- @@ -305,7 +293,7 @@ pprTerm p Term{dc=dc, subTerms=tt} pprTerm _ t = pprTerm1 t -pprTerm1 Prim{value=value} = text value +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} @@ -313,7 +301,8 @@ pprTerm1 Suspension{mb_ty=Just ty, bound_to=Just n} | otherwise = parens$ ppr n <> text "::" <> ppr ty -cPprTerm :: forall m. Monad m => ((Int->Term->m SDoc)->[Int->Term->m (Maybe SDoc)]) -> Term -> m SDoc +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)] @@ -341,7 +330,8 @@ cPprTermBase pprP = , ifTerm (isDC doubleDataCon) (coerceShow$ \(a::Double)->a) , ifTerm isIntegerDC (coerceShow$ \(a::Integer)->a) ] - where ifTerm pred f p t = if pred t then liftM Just (f p t) else return Nothing + 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] @@ -365,26 +355,231 @@ cPprTermBase pprP = getListTerms t@Suspension{} = [t] getListTerms t = pprPanic "getListTerms" (ppr t) +repPrim :: TyCon -> [Word] -> String +repPrim t = rep where + rep x + | t == charPrimTyCon = show (build x :: Char) + | t == intPrimTyCon = show (build x :: Int) + | t == wordPrimTyCon = show (build x :: Word) + | t == floatPrimTyCon = show (build x :: Float) + | t == doublePrimTyCon = show (build x :: Double) + | t == int32PrimTyCon = show (build x :: Int32) + | t == word32PrimTyCon = show (build x :: Word32) + | t == int64PrimTyCon = show (build x :: Int64) + | t == word64PrimTyCon = show (build x :: Word64) + | t == addrPrimTyCon = show (nullPtr `plusPtr` build x) + | t == stablePtrPrimTyCon = "" + | t == stableNamePrimTyCon = "" + | t == statePrimTyCon = "" + | t == realWorldTyCon = "" + | t == threadIdPrimTyCon = "" + | t == weakPrimTyCon = "" + | t == arrayPrimTyCon = "" + | t == byteArrayPrimTyCon = "" + | t == mutableArrayPrimTyCon = "" + | t == mutableByteArrayPrimTyCon = "" + | t == mutVarPrimTyCon= "" + | t == mVarPrimTyCon = "" + | 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 ----------------------------------- +{- +Type Reconstruction is type inference done on heap closures. +The algorithm walks the heap generating a set of equations, which +are solved with syntactic unification. +A type reconstruction equation looks like: + + = + +The full equation set is generated by traversing all the subterms, starting +from a given term. + +The only difficult part is that newtypes are only found in the lhs of equations. +Right hand sides are missing them. We can either (a) drop them from the lhs, or +(b) reconstruct them in the rhs when possible. + +The function congruenceNewtypes takes a shot at (b) +-} -- The Type Reconstruction monad type TR a = TcM a -runTR :: HscEnv -> TR Term -> IO Term +runTR :: HscEnv -> TR a -> IO a runTR hsc_env c = do - mb_term <- initTcPrintErrors hsc_env iNTERACTIVE (c >>= zonkTerm) + mb_term <- initTcPrintErrors hsc_env iNTERACTIVE c case mb_term of Nothing -> panic "Can't unify" - Just term -> return term + Just x -> return x trIO :: IO a -> TR a trIO = liftTcM . ioToTcRn +liftTcM = id + +newVar :: Kind -> TR TcTyVar +newVar = liftTcM . 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 + 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 + + +-- 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) + case mb_ty of + Nothing -> go tv tv hval >>= zonkTerm + Just ty | isMonomorphic ty -> go ty ty hval >>= zonkTerm + Just ty -> do + (ty',rev_subst) <- instScheme (sigmaType ty) + addConstraint tv ty' + term <- go 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 + 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 +-- We always follow indirections + Indirection _ -> go 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" + Just dc -> do + 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) + | (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 + when (not monomorphic) $ do + 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 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) +-- The otherwise case: can be a Thunk,AP,PAP,etc. + otherwise -> + return (Suspension (tipe clos) (Just tv) a Nothing) + + matchSubTypes dc ty + | Just (_,ty_args) <- splitTyConApp_maybe (repType ty) + , null (dataConExTyVars dc) --TODO case of extra existential tyvars + = dataConInstArgTys dc ty_args + + | otherwise = dataConRepArgTys dc + +-- This is used to put together pointed and nonpointed subterms in the +-- correct order. + reOrderTerms _ _ [] = [] + reOrderTerms pointed unpointed (ty:tys) + | isPointed ty = ASSERT2(not(null pointed) + , 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)) + head unpointed : reOrderTerms pointed (tail unpointed) tys + + + +-- Fast, breadth-first 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) + case mb_ty of + Nothing -> do search (isMonomorphic `fmap` zonkTcType tv) + (uncurry go) + [(tv, hval)] + zonkTcType tv -- TODO untested! + Just ty | isMonomorphic ty -> return ty + Just ty -> do + (ty',rev_subst) <- instScheme (sigmaType ty) + addConstraint tv ty' + search (isMonomorphic `fmap` zonkTcType tv) + (uncurry go) + [(tv, hval)] + substTy rev_subst `fmap` zonkTcType tv + where +-- search :: m Bool -> ([a] -> [a] -> [a]) -> [a] -> m () + search stop expand [] = return () + search stop expand (x:xx) = do new <- expand x + unlessM stop $ search stop expand (xx ++ new) + + -- returns unification tasks,since we are going to want a breadth-first search + go :: Type -> HValue -> TR [(Type, HValue)] + 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) + subTtypes <- mapMif (not . isMonomorphic) + (\t -> mkTyVarTy `fmap` 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 $ map (\(I# i#,t) -> case ptrs clos of + (Array _ _ ptrs#) -> case indexArray# ptrs# i# of + (# e #) -> (t,e)) + (drop extra_args $ zip [0..] subTtypes) + otherwise -> return [] + + +-- Dealing with newtypes {- A parallel fold over two Type values, compensating for missing newtypes on both sides. @@ -445,10 +640,13 @@ congruenceNewtypes = go True 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) + (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' + (args_l'', args_r'') <- unzip `liftM` zipWithM (go rewriteRHS) + args_l' + args_r' return (mkTyConApp tycon_l' args_l'', mkTyConApp tycon_r' args_r'') | otherwise = return (lhs,rhs) @@ -459,114 +657,22 @@ congruenceNewtypes = go True Just subst -> substTys subst (map mkTyVarTy tvs) otherwise -> panic "congruenceNewtypes: Can't unify a newtype" -newVar :: Kind -> TR TcTyVar -newVar = liftTcM . newFlexiTyVar -liftTcM = id +-------------------------------------------------------------------------------- --- | 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 - return (ty', zipTopTvSubst tvs' (mkTyVarTys tvs)) +isMonomorphic ty | (tvs, ty') <- splitForAllTys ty + = null tvs && (isEmptyVarSet . tyVarsOfType) ty' -cvObtainTerm :: HscEnv -> Bool -> Maybe Type -> HValue -> IO Term -cvObtainTerm hsc_env force mb_ty a = do - -- Obtain the term and tidy the type before returning it - term <- cvObtainTerm1 hsc_env force mb_ty a - return $ tidyTypes term - where - tidyTypes = foldTerm idTermFold { - fTerm = \ty dc hval tt -> Term (tidy ty) dc hval tt, - fSuspension = \ct mb_ty hval n -> - Suspension ct (fmap tidy mb_ty) hval n - } - tidy ty = tidyType (emptyTidyOccEnv, tidyVarEnv ty) ty - tidyVarEnv ty = mkVarEnv$ - [ (v, setTyVarName v (tyVarName tv)) - | (tv,v) <- zip alphaTyVars vars] - where vars = varSetElems$ tyVarsOfType ty - -cvObtainTerm1 :: HscEnv -> Bool -> Maybe Type -> HValue -> IO Term -cvObtainTerm1 hsc_env force mb_ty hval = runTR hsc_env $ do - tv <- liftM mkTyVarTy (newVar argTypeKind) - case mb_ty of - Nothing -> go tv tv hval - Just ty | isMonomorphic ty -> go ty ty hval - Just ty -> do - (ty',rev_subst) <- instScheme (sigmaType ty) - addConstraint tv ty' - term <- go tv tv hval - --restore original Tyvars - return$ flip foldTerm term idTermFold { - fTerm = \ty dc hval tt -> Term (substTy rev_subst ty) dc hval tt, - fSuspension = \ct mb_ty hval n -> - Suspension ct (substTy rev_subst `fmap` mb_ty) hval n} - 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 - clos <- trIO $ getClosureData a - case tipe clos of --- Thunks we may want to force - t | isThunk t && force -> seq a $ go tv ty a --- We always follow indirections - Indirection _ -> go 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" - Just dc -> do - 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) - | (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. - 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 - | (i,tv,t) <- zip3 [0..] subTermTvs subTtypesP] - let unboxeds = extractUnboxed subTtypesNP (nonPtrs clos) - subTermsNP = map (uncurry Prim) (zip subTtypesNP unboxeds) - subTerms = reOrderTerms subTermsP subTermsNP (drop extra_args subTtypes) - return (Term tv dc a subTerms) --- The otherwise case: can be a Thunk,AP,PAP,etc. - otherwise -> - return (Suspension (tipe clos) (Just tv) a Nothing) +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 --- Access the array of pointers and recurse down. Needs to be done with --- care of no introducing a thunk! or go will fail to do its job - appArr f arr (I# i#) = case arr of - (Array _ _ ptrs#) -> case indexArray# ptrs# i# of - (# e #) -> f e +unlessM condM acc = condM >>= \c -> unless c acc - matchSubTypes dc ty - | Just (_,ty_args) <- splitTyConApp_maybe (repType ty) - , null (dataConExTyVars dc) --TODO Handle the case of extra existential tyvars - = dataConInstArgTys dc ty_args - - | otherwise = dataConRepArgTys dc - --- This is used to put together pointed and nonpointed subterms in the --- correct order. - reOrderTerms _ _ [] = [] - reOrderTerms pointed unpointed (ty:tys) - | isPointed ty = ASSERT2(not(null pointed) - , 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)) - head unpointed : reOrderTerms pointed (tail unpointed) tys - -isMonomorphic ty | isForAllTy ty = False -isMonomorphic ty = (isEmptyVarSet . tyVarsOfType) ty +-- Strict application of f at index i +appArr f (Array _ _ ptrs#) (I# i#) = case indexArray# ptrs# i# of + (# e #) -> f e zonkTerm :: Term -> TcM Term zonkTerm = foldTerm idTermFoldM { @@ -581,53 +687,4 @@ zonkTerm = foldTerm idTermFoldM { -- Generalize the type: find all free tyvars and wrap in the appropiate ForAll. sigmaType ty = mkForAllTys (varSetElems$ tyVarsOfType (dropForAlls ty)) ty -{- -Example of Type Reconstruction --------------------------------- -Suppose we have an existential type such as - -data Opaque = forall a. Opaque a -And we have a term built as: - -t = Opaque (map Just [[1,1],[2,2]]) - -The type of t as far as the typechecker goes is t :: Opaque -If we seq the head of t, we obtain: - -t - O (_1::a) - -seq _1 () - -t - O ( (_3::b) : (_4::[b]) ) - -seq _3 () - -t - O ( (Just (_5::c)) : (_4::[b]) ) - -At this point, we know that b = (Maybe c) - -seq _5 () - -t - O ( (Just ((_6::d) : (_7::[d]) )) : (_4::[b]) ) - -At this point, we know that c = [d] - -seq _6 () - -t - O ( (Just (1 : (_7::[d]) )) : (_4::[b]) ) - -At this point, we know that d = Integer - -The fully reconstructed expressions, with propagation, would be: - -t - O ( (Just (_5::c)) : (_4::[Maybe c]) ) -t - O ( (Just ((_6::d) : (_7::[d]) )) : (_4::[Maybe [d]]) ) -t - O ( (Just (1 : (_7::[Integer]) )) : (_4::[Maybe [Integer]]) ) - - -For reference, the type of the thing inside the opaque is -map Just [[1,1],[2,2]] :: [Maybe [Integer]] - -NOTE: (Num t) contexts have been manually replaced by Integer for clarity --}