X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2Fghci%2FRtClosureInspect.hs;h=b6c97c38aabad0d4a3c7cbb9ae27b21115bcf3a0;hp=1b8616aaabcd2e9a74f8f05374344d7dcb47e45a;hb=b2524b3960999fffdb3767900f58825903f6560f;hpb=131320a1b79d965540449927b640ab037fb7a13a diff --git a/compiler/ghci/RtClosureInspect.hs b/compiler/ghci/RtClosureInspect.hs index 1b8616a..b6c97c3 100644 --- a/compiler/ghci/RtClosureInspect.hs +++ b/compiler/ghci/RtClosureInspect.hs @@ -7,95 +7,73 @@ ----------------------------------------------------------------------------- module RtClosureInspect( - cvObtainTerm, -- :: HscEnv -> Int -> Bool -> Maybe Type -> HValue -> IO Term - - Term(..), - isTerm, - isSuspension, - isPrim, - isNewtypeWrap, - pprTerm, - cPprTerm, - cPprTermBase, - CustomTermPrinter, - termType, - foldTerm, - TermFold(..), - idTermFold, - idTermFoldM, - isFullyEvaluated, - isPointed, - isFullyEvaluatedTerm, - mapTermType, - termTyVars, --- unsafeDeepSeq, cvReconstructType, improveRTTIType, - sigmaType, - Closure(..), - getClosureData, - ClosureType(..), - isConstr, - isIndirection - ) where + + Term(..), + isTerm, isSuspension, isPrim, isFun, isFunLike, isNewtypeWrap, + isFullyEvaluated, isFullyEvaluatedTerm, + termType, mapTermType, termTyVars, + foldTerm, TermFold(..), foldTermM, TermFoldM(..), idTermFold, + pprTerm, cPprTerm, cPprTermBase, CustomTermPrinter, + +-- unsafeDeepSeq, + + Closure(..), getClosureData, ClosureType(..), isConstr, isIndirection + ) where #include "HsVersions.h" import ByteCodeItbls ( StgInfoTable ) import qualified ByteCodeItbls as BCI( StgInfoTable(..) ) -import HscTypes ( HscEnv ) +import HscTypes import Linker import DataCon import Type +import qualified Unify as U +import TypeRep -- I know I know, this is cheating import Var import TcRnMonad import TcType import TcMType import TcUnify import TcEnv -import DriverPhases + import TyCon import Name import VarEnv import Util import VarSet - import TysPrim import PrelNames import TysWiredIn - -import Outputable +import DynFlags +import Outputable as Ppr import FastString -import Panic - import Constants ( wORD_SIZE ) - import GHC.Arr ( Array(..) ) import GHC.Exts -import GHC.IOBase ( IO(IO) ) +import GHC.IO ( IO(..) ) +import StaticFlags( opt_PprStyle_Debug ) import Control.Monad import Data.Maybe import Data.Array.Base import Data.Ix -import Data.List ( partition ) +import Data.List import qualified Data.Sequence as Seq import Data.Monoid -import Data.Sequence hiding (null, length, index, take, drop, splitAt, reverse) -import Foreign +import Data.Sequence (viewl, ViewL(..)) +import Foreign hiding (unsafePerformIO) import System.IO.Unsafe -import System.IO --------------------------------------------- -- * A representation of semi evaluated Terms --------------------------------------------- -{- --} - -data Term = Term { ty :: Type +data Term = Term { ty :: RttiType , dc :: Either String DataCon -- Carries a text representation if the datacon is -- not exported by the .hi file, which is the case @@ -103,21 +81,26 @@ data Term = Term { ty :: Type , val :: HValue , subTerms :: [Term] } - | Prim { ty :: Type + | Prim { ty :: RttiType , value :: [Word] } | Suspension { ctype :: ClosureType - , ty :: Type + , ty :: RttiType , val :: HValue , bound_to :: Maybe Name -- Useful for printing } - | NewtypeWrap{ ty :: Type + | NewtypeWrap{ -- At runtime there are no newtypes, and hence no + -- newtype constructors. A NewtypeWrap is just a + -- made-up tag saying "heads up, there used to be + -- a newtype constructor here". + ty :: RttiType , dc :: Either String DataCon , wrapped_term :: Term } - | RefWrap { ty :: Type + | RefWrap { -- The contents of a reference + ty :: RttiType , wrapped_term :: Term } -isTerm, isSuspension, isPrim, isNewtypeWrap :: Term -> Bool +isTerm, isSuspension, isPrim, isFun, isFunLike, isNewtypeWrap :: Term -> Bool isTerm Term{} = True isTerm _ = False isSuspension Suspension{} = True @@ -127,7 +110,13 @@ isPrim _ = False isNewtypeWrap NewtypeWrap{} = True isNewtypeWrap _ = False -termType :: Term -> Type +isFun Suspension{ctype=Fun} = True +isFun _ = False + +isFunLike s@Suspension{ty=ty} = isFun s || isFunTy ty +isFunLike _ = False + +termType :: Term -> RttiType termType t = ty t isFullyEvaluatedTerm :: Term -> Bool @@ -153,6 +142,7 @@ data ClosureType = Constr | PAP | Indirection Int | MutVar Int + | MVar Int | Other Int deriving (Show, Eq) @@ -166,7 +156,7 @@ data Closure = Closure { tipe :: ClosureType instance Outputable ClosureType where ppr = text . show -#include "../includes/ClosureTypes.h" +#include "../includes/rts/storage/ClosureTypes.h" aP_CODE, pAP_CODE :: Int aP_CODE = AP @@ -193,7 +183,7 @@ getClosureData a = 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)] ] + | I# i <- [0.. fromIntegral (BCI.nptrs itbl)-1] ] ASSERT(elems >= 0) return () ptrsList `seq` return (Closure tipe (Ptr iptr) itbl ptrsList nptrs_data) @@ -209,7 +199,8 @@ readCType i | i' == aP_CODE = AP | i == AP_STACK = AP | i' == pAP_CODE = PAP - | i == MUT_VAR_CLEAN || i == MUT_VAR_DIRTY = MutVar i' + | i == MUT_VAR_CLEAN || i == MUT_VAR_DIRTY= MutVar i' + | i == MVAR_CLEAN || i == MVAR_DIRTY = MVar i' | otherwise = Other i' where i' = fromIntegral i @@ -234,11 +225,6 @@ isFullyEvaluated a = do _ -> 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 - -- TODO: Fix it. Probably the otherwise case is failing, trace/debug it {- unsafeDeepSeq :: a -> b -> b @@ -251,37 +237,30 @@ unsafeDeepSeq = unsafeDeepSeq1 2 closure -> foldl' (flip unsafeDeepSeq) b (ptrs closure) where tipe = unsafePerformIO (getClosureType a) -} -isPointed :: Type -> Bool -isPointed t | Just (t, _) <- splitTyConApp_maybe t - = not$ isUnliftedTypeKind (tyConKind t) -isPointed _ = True - -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) xx - = x : go tt rest - -sizeofTyCon :: TyCon -> Int -- in *words* -sizeofTyCon = primRepSizeW . tyConPrimRep ----------------------------------- -- * Traversals for Terms ----------------------------------- -type TermProcessor a b = Type -> Either String DataCon -> HValue -> [a] -> b +type TermProcessor a b = RttiType -> Either String DataCon -> HValue -> [a] -> b data TermFold a = TermFold { fTerm :: TermProcessor a a - , fPrim :: Type -> [Word] -> a - , fSuspension :: ClosureType -> Type -> HValue + , fPrim :: RttiType -> [Word] -> a + , fSuspension :: ClosureType -> RttiType -> HValue -> Maybe Name -> a - , fNewtypeWrap :: Type -> Either String DataCon + , fNewtypeWrap :: RttiType -> Either String DataCon -> a -> a - , fRefWrap :: Type -> a -> a + , fRefWrap :: RttiType -> a -> a + } + + +data TermFoldM m a = + TermFoldM {fTermM :: TermProcessor a (m a) + , fPrimM :: RttiType -> [Word] -> m a + , fSuspensionM :: ClosureType -> RttiType -> HValue + -> Maybe Name -> m a + , fNewtypeWrapM :: RttiType -> Either String DataCon + -> a -> m a + , fRefWrapM :: RttiType -> a -> m a } foldTerm :: TermFold a -> Term -> a @@ -291,6 +270,14 @@ 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) foldTerm tf (RefWrap ty t) = fRefWrap tf ty (foldTerm tf t) + +foldTermM :: Monad m => TermFoldM m a -> Term -> m a +foldTermM tf (Term ty dc v tt) = mapM (foldTermM tf) tt >>= fTermM tf ty dc v +foldTermM tf (Prim ty v ) = fPrimM tf ty v +foldTermM tf (Suspension ct ty v b) = fSuspensionM tf ct ty v b +foldTermM tf (NewtypeWrap ty dc t) = foldTermM tf t >>= fNewtypeWrapM tf ty dc +foldTermM tf (RefWrap ty t) = foldTermM tf t >>= fRefWrapM tf ty + idTermFold :: TermFold Term idTermFold = TermFold { fTerm = Term, @@ -299,16 +286,8 @@ idTermFold = TermFold { fNewtypeWrap = NewtypeWrap, fRefWrap = RefWrap } -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, - fNewtypeWrap= \ty dc t -> NewtypeWrap ty dc `liftM` t, - fRefWrap = \ty t -> RefWrap ty `liftM` t - } -mapTermType :: (Type -> Type) -> Term -> Term +mapTermType :: (RttiType -> Type) -> Term -> Term mapTermType f = foldTerm idTermFold { fTerm = \ty dc hval tt -> Term (f ty) dc hval tt, fSuspension = \ct ty hval n -> @@ -316,6 +295,15 @@ mapTermType f = foldTerm idTermFold { fNewtypeWrap= \ty dc t -> NewtypeWrap (f ty) dc t, fRefWrap = \ty t -> RefWrap (f ty) t} +mapTermTypeM :: Monad m => (RttiType -> m Type) -> Term -> m Term +mapTermTypeM f = foldTermM TermFoldM { + fTermM = \ty dc hval tt -> f ty >>= \ty' -> return $ Term ty' dc hval tt, + fPrimM = (return.) . Prim, + fSuspensionM = \ct ty hval n -> + f ty >>= \ty' -> return $ Suspension ct ty' hval n, + fNewtypeWrapM= \ty dc t -> f ty >>= \ty' -> return $ NewtypeWrap ty' dc t, + fRefWrapM = \ty t -> f ty >>= \ty' -> return $ RefWrap ty' t} + termTyVars :: Term -> TyVarSet termTyVars = foldTerm TermFold { fTerm = \ty _ _ tt -> @@ -355,10 +343,17 @@ ppr_termM y p Term{dc=Right dc, subTerms=tt} = parens (ppr_term1 True t1 <+> ppr dc <+> ppr_term1 True ppr t2) <+> hsep (map (ppr_term1 True) tt) -} -- TODO Printing infix constructors properly - | null tt = return$ ppr dc - | otherwise = do - tt_docs <- mapM (y app_prec) tt - return$ cparen (p >= app_prec) (ppr dc <+> pprDeeperList fsep tt_docs) + | null sub_terms_to_show + = return (ppr dc) + | otherwise + = do { tt_docs <- mapM (y app_prec) sub_terms_to_show + ; return $ cparen (p >= app_prec) $ + sep [ppr dc, nest 2 (pprDeeperList fsep tt_docs)] } + where + sub_terms_to_show -- Don't show the dictionary arguments to + -- constructors unless -dppr-debug is on + | opt_PprStyle_Debug = tt + | otherwise = dropList (dataConTheta dc) tt ppr_termM y p t@NewtypeWrap{} = pprNewtypeWrap y p t ppr_termM y p RefWrap{wrapped_term=t} = do @@ -375,20 +370,21 @@ ppr_termM _ _ t = ppr_termM1 t ppr_termM1 :: Monad m => Term -> m SDoc ppr_termM1 Prim{value=words, ty=ty} = return$ text$ repPrim (tyConAppTyCon ty) words -ppr_termM1 Suspension{bound_to=Nothing} = return$ char '_' +ppr_termM1 Suspension{ty=ty, bound_to=Nothing} = + return (char '_' <+> ifPprDebug (text "::" <> ppr ty)) ppr_termM1 Suspension{ty=ty, bound_to=Just n} - | Just _ <- splitFunTy_maybe ty = return$ ptext (sLit "") +-- | Just _ <- splitFunTy_maybe ty = return$ ptext (sLit("") | otherwise = return$ parens$ ppr n <> text "::" <> ppr ty ppr_termM1 Term{} = panic "ppr_termM1 - Term" ppr_termM1 RefWrap{} = panic "ppr_termM1 - RefWrap" ppr_termM1 NewtypeWrap{} = panic "ppr_termM1 - NewtypeWrap" -pprNewtypeWrap y p NewtypeWrap{ty=ty, wrapped_term=t} - | Just (tc,_) <- splitNewTyConApp_maybe ty +pprNewtypeWrap y p NewtypeWrap{ty=ty, wrapped_term=t} + | Just (tc,_) <- tcSplitTyConApp_maybe ty , ASSERT(isNewTyCon tc) True - , Just new_dc <- maybeTyConSingleCon tc = do - real_term <- y max_prec t - return$ cparen (p >= app_prec) (ppr new_dc <+> real_term) + , Just new_dc <- tyConSingleDataCon_maybe tc = do + real_term <- y max_prec t + return $ cparen (p >= app_prec) (ppr new_dc <+> real_term) pprNewtypeWrap _ _ _ = panic "pprNewtypeWrap" ------------------------------------------------------- @@ -422,54 +418,70 @@ cPprTerm printers_ = go 0 where firstJustM [] = return Nothing -- Default set of custom printers. Note that the recursion knot is explicit -cPprTermBase :: Monad m => CustomTermPrinter m +cPprTermBase :: forall m. Monad m => CustomTermPrinter m cPprTermBase y = [ 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) + ppr_list + , ifTerm (isTyCon intTyCon . ty) ppr_int + , ifTerm (isTyCon charTyCon . ty) ppr_char + , ifTerm (isTyCon floatTyCon . ty) ppr_float + , ifTerm (isTyCon doubleTyCon . ty) ppr_double + , ifTerm (isIntegerTy . ty) ppr_integer ] - 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 ty = fromMaybe False $ do - (tc,_) <- splitTyConApp_maybe ty - return (tc `elem` (fst.unzip.elems) boxedTupleArr) - - isTyCon a_tc ty = fromMaybe False $ do - (tc,_) <- splitTyConApp_maybe ty - return (a_tc == tc) - - coerceShow f _p = return . text . show . f . unsafeCoerce# . val - - --Note pprinting of list terms is not lazy - doList p h t = do - let elems = h : getListTerms t - isConsLast = not(termType(last elems) `coreEqType` termType h) - print_elems <- mapM (y cons_prec) elems - return$ if isConsLast - then cparen (p >= cons_prec) - . pprDeeperList fsep - . punctuate (space<>colon) - $ print_elems - else brackets (pprDeeperList fcat$ - punctuate comma print_elems) - - where getListTerms Term{subTerms=[h,t]} = h : getListTerms t - getListTerms Term{subTerms=[]} = [] - getListTerms t@Suspension{} = [t] - getListTerms t = pprPanic "getListTerms" (ppr t) + where + ifTerm :: (Term -> Bool) + -> (Precedence -> Term -> m SDoc) + -> Precedence -> Term -> m (Maybe SDoc) + ifTerm pred f prec t@Term{} + | pred t = Just `liftM` f prec t + ifTerm _ _ _ _ = return Nothing + + isTupleTy ty = fromMaybe False $ do + (tc,_) <- tcSplitTyConApp_maybe ty + return (isBoxedTupleTyCon tc) + + isTyCon a_tc ty = fromMaybe False $ do + (tc,_) <- tcSplitTyConApp_maybe ty + return (a_tc == tc) + + isIntegerTy ty = fromMaybe False $ do + (tc,_) <- tcSplitTyConApp_maybe ty + return (tyConName tc == integerTyConName) + + ppr_int, ppr_char, ppr_float, ppr_double, ppr_integer + :: Precedence -> Term -> m SDoc + ppr_int _ v = return (Ppr.int (unsafeCoerce# (val v))) + ppr_char _ v = return (Ppr.char '\'' <> Ppr.char (unsafeCoerce# (val v)) <> Ppr.char '\'') + ppr_float _ v = return (Ppr.float (unsafeCoerce# (val v))) + ppr_double _ v = return (Ppr.double (unsafeCoerce# (val v))) + ppr_integer _ v = return (Ppr.integer (unsafeCoerce# (val v))) + + --Note pprinting of list terms is not lazy + ppr_list :: Precedence -> Term -> m SDoc + ppr_list p (Term{subTerms=[h,t]}) = do + let elems = h : getListTerms t + isConsLast = not(termType(last elems) `eqType` termType h) + is_string = all (isCharTy . ty) elems + + print_elems <- mapM (y cons_prec) elems + if is_string + then return (Ppr.doubleQuotes (Ppr.text (unsafeCoerce# (map val elems)))) + else if isConsLast + then return $ cparen (p >= cons_prec) + $ pprDeeperList fsep + $ punctuate (space<>colon) print_elems + else return $ brackets + $ pprDeeperList fcat + $ punctuate comma print_elems + + where getListTerms Term{subTerms=[h,t]} = h : getListTerms t + getListTerms Term{subTerms=[]} = [] + getListTerms t@Suspension{} = [t] + getListTerms t = pprPanic "getListTerms" (ppr t) + ppr_list _ _ = panic "doList" repPrim :: TyCon -> [Word] -> String @@ -524,21 +536,45 @@ Right hand sides are missing them. We can either (a) drop them from the lhs, or The function congruenceNewtypes takes a shot at (b) -} + +-- A (non-mutable) tau type containing +-- existentially quantified tyvars. +-- (since GHC type language currently does not support +-- existentials, we leave these variables unquantified) +type RttiType = Type + +-- An incomplete type as stored in GHCi: +-- no polymorphism: no quantifiers & all tyvars are skolem. +type GhciType = Type + + -- The Type Reconstruction monad +-------------------------------- type TR a = TcM a runTR :: HscEnv -> TR a -> IO a -runTR hsc_env c = do - mb_term <- runTR_maybe hsc_env c - case mb_term of - Nothing -> panic "Can't unify" +runTR hsc_env thing = do + mb_val <- runTR_maybe hsc_env thing + case mb_val of + Nothing -> error "unable to :print the term" Just x -> return x 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 +traceTR = liftTcM . traceOptTcRn Opt_D_dump_rtti + + +-- Semantically different to recoverM in TcRnMonad +-- recoverM retains the errors in the first action, +-- whereas recoverTc here does not +recoverTR :: TR a -> TR a -> TR a +recoverTR recover thing = do + (_,mb_res) <- tryTcErrs thing + case mb_res of + Nothing -> recover + Just res -> return res trIO :: IO a -> TR a trIO = liftTcM . liftIO @@ -547,14 +583,40 @@ liftTcM :: TcM a -> TR a liftTcM = id newVar :: Kind -> TR TcType -newVar = liftTcM . fmap mkTyVarTy . newBoxyTyVar - --- | 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)) +newVar = liftTcM . newFlexiTyVarTy + +instTyVars :: [TyVar] -> TR ([TcTyVar], [TcType], TvSubst) +-- Instantiate fresh mutable type variables from some TyVars +-- This function preserves the print-name, which helps error messages +instTyVars = liftTcM . tcInstTyVars + +type RttiInstantiation = [(TcTyVar, TyVar)] + -- Associates the typechecker-world meta type variables + -- (which are mutable and may be refined), to their + -- debugger-world RuntimeUnk counterparts. + -- If the TcTyVar has not been refined by the runtime type + -- elaboration, then we want to turn it back into the + -- original RuntimeUnk + +-- | Returns the instantiated type scheme ty', and the +-- mapping from new (instantiated) -to- old (skolem) type variables +instScheme :: QuantifiedType -> TR (TcType, RttiInstantiation) +instScheme (tvs, ty) + = liftTcM $ do { (tvs', _, subst) <- tcInstTyVars tvs + ; let rtti_inst = [(tv',tv) | (tv',tv) <- tvs' `zip` tvs] + ; return (substTy subst ty, rtti_inst) } + +applyRevSubst :: RttiInstantiation -> TR () +-- Apply the *reverse* substitution in-place to any un-filled-in +-- meta tyvars. This recovers the original debugger-world variable +-- unless it has been refined by new information from the heap +applyRevSubst pairs = liftTcM (mapM_ do_pair pairs) + where + do_pair (tc_tv, rtti_tv) + = do { tc_ty <- zonkTcTyVar tc_tv + ; case tcGetTyVar_maybe tc_ty of + Just tv | isMetaTyVar tv -> writeMetaTyVar tv (mkTyVarTy rtti_tv) + _ -> return () } -- Adds a constraint of the form t1 == t2 -- t1 is expected to come from walking the heap @@ -562,57 +624,114 @@ instScheme ty | (tvs, _rho) <- tcSplitForAllTys ty = liftTcM$ do -- Before unification, congruenceNewtypes needs to -- do its magic. addConstraint :: TcType -> TcType -> TR () -addConstraint t1 t2 = congruenceNewtypes t1 t2 >>= uncurry boxyUnify - >> return () -- TOMDO: what about the coercion? - -- we should consider family instances - --- Type & Term reconstruction -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 - >>= 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$ expandNewtypes $ mapTermType (substTy rev_subst) term +addConstraint actual expected = do + traceTR (text "add constraint:" <+> fsep [ppr actual, equals, ppr expected]) + recoverTR (traceTR $ fsep [text "Failed to unify", ppr actual, + text "with", ppr expected]) $ + do { (ty1, ty2) <- congruenceNewtypes actual expected + ; _ <- captureConstraints $ unifyType ty1 ty2 + ; return () } + -- TOMDO: what about the coercion? + -- we should consider family instances + + +-- Type & Term reconstruction +------------------------------ +cvObtainTerm :: HscEnv -> Int -> Bool -> RttiType -> HValue -> IO Term +cvObtainTerm hsc_env max_depth force old_ty hval = runTR hsc_env $ do + -- we quantify existential tyvars as universal, + -- as this is needed to be able to manipulate + -- them properly + let quant_old_ty@(old_tvs, old_tau) = quantifyType old_ty + sigma_old_ty = mkForAllTys old_tvs old_tau + traceTR (text "Term reconstruction started with initial type " <> ppr old_ty) + term <- + if null old_tvs + then do + term <- go max_depth sigma_old_ty sigma_old_ty hval + term' <- zonkTerm term + return $ fixFunDictionaries $ expandNewtypes term' + else do + (old_ty', rev_subst) <- instScheme quant_old_ty + my_ty <- newVar argTypeKind + when (check1 quant_old_ty) (traceTR (text "check1 passed") >> + addConstraint my_ty old_ty') + term <- go max_depth my_ty sigma_old_ty hval + new_ty <- zonkTcType (termType term) + if isMonomorphic new_ty || check2 (quantifyType new_ty) quant_old_ty + then do + traceTR (text "check2 passed") + addConstraint new_ty old_ty' + applyRevSubst rev_subst + zterm' <- zonkTerm term + return ((fixFunDictionaries . expandNewtypes) zterm') + else do + traceTR (text "check2 failed" <+> parens + (ppr term <+> text "::" <+> ppr new_ty)) + -- we have unsound types. Replace constructor types in + -- subterms with tyvars + zterm' <- mapTermTypeM + (\ty -> case tcSplitTyConApp_maybe ty of + Just (tc, _:_) | tc /= funTyCon + -> newVar argTypeKind + _ -> return ty) + term + zonkTerm zterm' + traceTR (text "Term reconstruction completed." $$ + text "Term obtained: " <> ppr term $$ + text "Type obtained: " <> ppr (termType term)) + return term where - go bound _ _ _ | seq bound False = undefined - go 0 tv _ty a = do + + go :: Int -> Type -> Type -> HValue -> TcM Term + -- [SPJ May 11] I don't understand the difference between my_ty and old_ty + + go max_depth _ _ _ | seq max_depth False = undefined + go 0 my_ty _old_ty a = do + traceTR (text "Gave up reconstructing a term after" <> + int max_depth <> text " steps") clos <- trIO $ getClosureData a - return (Suspension (tipe clos) tv a Nothing) - go bound tv ty a = do - let monomorphic = not(isTyVarTy tv) + return (Suspension (tipe clos) my_ty a Nothing) + go max_depth my_ty old_ty a = do + let monomorphic = not(isTyVarTy my_ty) -- 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 (pred bound) tv ty a --- We always follow indirections - Indirection _ -> go bound tv ty $! (ptrs clos ! 0) + t | isThunk t && force -> traceTR (text "Forcing a " <> text (show t)) >> + seq a (go (pred max_depth) my_ty old_ty a) +-- Blackholes are indirections iff the payload is not TSO or BLOCKING_QUEUE. So we +-- treat them like indirections; if the payload is TSO or BLOCKING_QUEUE, we'll end up +-- showing '_' which is what we want. + Blackhole -> do traceTR (text "Following a BLACKHOLE") + appArr (go max_depth my_ty old_ty) (ptrs clos) 0 +-- We always follow indirections + Indirection i -> do traceTR (text "Following an indirection" <> parens (int i) ) + go max_depth my_ty old_ty $! (ptrs clos ! 0) -- We also follow references - MutVar _ | Just (tycon,[world,ty_contents]) <- splitTyConApp_maybe ty - -- , tycon == mutVarPrimTyCon + MutVar _ | Just (tycon,[world,contents_ty]) <- tcSplitTyConApp_maybe old_ty -> do + -- Deal with the MutVar# primitive + -- It does not have a constructor at all, + -- so we simulate the following one + -- MutVar# :: contents_ty -> MutVar# s contents_ty + traceTR (text "Following a MutVar") + contents_tv <- newVar liftedTypeKind contents <- trIO$ IO$ \w -> readMutVar# (unsafeCoerce# a) w - tv' <- newVar liftedTypeKind - addConstraint tv (mkTyConApp tycon [world,tv']) - x <- go bound tv' ty_contents contents - return (RefWrap ty x) + ASSERT(isUnliftedTypeKind $ typeKind my_ty) return () + (mutvar_ty,_) <- instScheme $ quantifyType $ mkFunTy + contents_ty (mkTyConApp tycon [world,contents_ty]) + addConstraint (mkFunTy contents_tv my_ty) mutvar_ty + x <- go (pred max_depth) contents_tv contents_ty contents + return (RefWrap my_ty x) -- The interesting case Constr -> do + traceTR (text "entering a constructor " <> + if monomorphic + then parens (text "already monomorphic: " <> ppr my_ty) + else Ppr.empty) Right dcname <- dataConInfoPtrToName (infoPtr clos) (_,mb_dc) <- tryTcErrs (tcLookupDataCon dcname) case mb_dc of @@ -621,55 +740,34 @@ cvObtainTerm hsc_env bound force mb_ty hval = runTR hsc_env $ do -- In such case, we return a best approximation: -- ignore the unpointed args, and recover the pointeds -- This preserves laziness, and should be safe. + traceTR (text "Nothing" <+> ppr dcname) let tag = showSDoc (ppr dcname) vars <- replicateM (length$ elems$ ptrs clos) - (newVar (liftedTypeKind)) - subTerms <- sequence [appArr (go (pred bound) tv tv) (ptrs clos) i + (newVar liftedTypeKind) + subTerms <- sequence [appArr (go (pred max_depth) 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) - subTtypes = matchSubTypes dc ty - (subTtypesP, subTtypesNP) = partition isPointed subTtypes - subTermTvs <- sequence - [ 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 - 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 (pred bound) tv t) (ptrs clos) i - | (i,tv,t) <- zip3 [0..] subTermTvs subTtypesP] + return (Term my_ty (Left ('<' : tag ++ ">")) a subTerms) + Just dc -> do + traceTR (text "Just" <+> ppr dc) + subTtypes <- getDataConArgTys dc my_ty + let (subTtypesP, subTtypesNP) = partition isPtrType subTtypes + subTermsP <- sequence + [ appArr (go (pred max_depth) ty ty) (ptrs clos) i + | (i,ty) <- zip [0..] subTtypesP] let unboxeds = extractUnboxed subTtypesNP clos - subTermsNP = map (uncurry Prim) (zip subTtypesNP unboxeds) - subTerms = reOrderTerms subTermsP subTermsNP - (drop extra_args subTtypes) - return (Term tv (Right dc) a subTerms) + subTermsNP = zipWith Prim subTtypesNP unboxeds + subTerms = reOrderTerms subTermsP subTermsNP subTtypes + return (Term my_ty (Right dc) a subTerms) + -- The otherwise case: can be a Thunk,AP,PAP,etc. tipe_clos -> - return (Suspension tipe_clos tv a Nothing) + return (Suspension tipe_clos my_ty a Nothing) - matchSubTypes dc ty - | Just (_,ty_args) <- splitTyConApp_maybe (repType ty) --- 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 --- correct order. + -- put together pointed and nonpointed subterms in the + -- correct order. reOrderTerms _ _ [] = [] reOrderTerms pointed unpointed (ty:tys) - | isPointed ty = ASSERT2(not(null pointed) + | isPtrType ty = ASSERT2(not(null pointed) , ptext (sLit "reOrderTerms") $$ (ppr pointed $$ ppr unpointed)) let (t:tt) = pointed in t : reOrderTerms tt unpointed tys @@ -677,41 +775,55 @@ cvObtainTerm hsc_env bound force mb_ty hval = runTR hsc_env $ do , ptext (sLit "reOrderTerms") $$ (ppr pointed $$ ppr unpointed)) 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 } + -- insert NewtypeWraps around newtypes + expandNewtypes = foldTerm idTermFold { fTerm = worker } where + worker ty dc hval tt + | Just (tc, args) <- tcSplitTyConApp_maybe ty + , isNewTyCon tc + , wrapped_type <- newTyConInstRhs tc args + , Just dc' <- tyConSingleDataCon_maybe tc + , t' <- worker wrapped_type dc hval tt + = NewtypeWrap ty (Right dc') t' + | otherwise = Term ty dc hval tt + - expandNewtypes t = t + -- Avoid returning types where predicates have been expanded to dictionaries. + fixFunDictionaries = foldTerm idTermFold {fSuspension = worker} where + worker ct ty hval n | isFunTy ty = Suspension ct (dictsView ty) hval n + | otherwise = Suspension ct ty hval n -- Fast, breadth-first Type reconstruction -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) - (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) - addConstraint tv ty' - search (isMonomorphic `fmap` zonkTcType tv) - (\(ty,a) -> go ty a) - (Seq.singleton (tv, hval)) - max_depth - substTy rev_subst `fmap` zonkTcType tv - where +------------------------------------------ +cvReconstructType :: HscEnv -> Int -> GhciType -> HValue -> IO (Maybe Type) +cvReconstructType hsc_env max_depth old_ty hval = runTR_maybe hsc_env $ do + traceTR (text "RTTI started with initial type " <> ppr old_ty) + let sigma_old_ty@(old_tvs, _) = quantifyType old_ty + new_ty <- + if null old_tvs + then return old_ty + else do + (old_ty', rev_subst) <- instScheme sigma_old_ty + my_ty <- newVar argTypeKind + when (check1 sigma_old_ty) (traceTR (text "check1 passed") >> + addConstraint my_ty old_ty') + search (isMonomorphic `fmap` zonkTcType my_ty) + (\(ty,a) -> go ty a) + (Seq.singleton (my_ty, hval)) + max_depth + new_ty <- zonkTcType my_ty + if isMonomorphic new_ty || check2 (quantifyType new_ty) sigma_old_ty + then do + traceTR (text "check2 passed" <+> ppr old_ty $$ ppr new_ty) + addConstraint my_ty old_ty' + applyRevSubst rev_subst + zonkRttiType new_ty + else traceTR (text "check2 failed" <+> parens (ppr new_ty)) >> + return old_ty + traceTR (text "RTTI completed. Type obtained:" <+> ppr new_ty) + return new_ty + where -- search :: m Bool -> ([a] -> [a] -> [a]) -> [a] -> m () search _ _ _ 0 = traceTR (text "Failed to reconstruct a type after " <> int max_depth <> text " steps") @@ -724,19 +836,21 @@ cvReconstructType hsc_env max_depth mb_ty hval = runTR_maybe hsc_env $ do -- returns unification tasks,since we are going to want a breadth-first search go :: Type -> HValue -> TR [(Type, HValue)] - go tv a = do + go my_ty a = do + traceTR (text "go" <+> ppr my_ty) clos <- trIO $ getClosureData a case tipe clos of - Indirection _ -> go tv $! (ptrs clos ! 0) + Blackhole -> appArr (go my_ty) (ptrs clos) 0 -- carefully, don't eval the TSO + Indirection _ -> go my_ty $! (ptrs clos ! 0) MutVar _ -> do contents <- trIO$ IO$ \w -> readMutVar# (unsafeCoerce# a) w tv' <- newVar liftedTypeKind world <- newVar liftedTypeKind - addConstraint tv (mkTyConApp mutVarPrimTyCon [world,tv']) --- x <- go tv' ty_contents contents + addConstraint my_ty (mkTyConApp mutVarPrimTyCon [world,tv']) return [(tv', contents)] Constr -> do Right dcname <- dataConInfoPtrToName (infoPtr clos) + traceTR (text "Constr1" <+> ppr dcname) (_,mb_dc) <- tryTcErrs (tcLookupDataCon dcname) case mb_dc of Nothing-> do @@ -746,44 +860,182 @@ cvReconstructType hsc_env max_depth mb_ty hval = runTR_maybe hsc_env $ do 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 -> 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..] (filter isPointed subTtypes)] + arg_tys <- getDataConArgTys dc my_ty + traceTR (text "Constr2" <+> ppr dcname <+> ppr arg_tys) + return $ [ appArr (\e-> (ty,e)) (ptrs clos) i + | (i,ty) <- zip [0..] (filter isPtrType arg_tys)] _ -> return [] -- Compute the difference between a base type and the type found by RTTI -- improveType -- The types can contain skolem type variables, which need to be treated as normal vars. -- In particular, we want them to unify with things. -improveRTTIType :: HscEnv -> Type -> Type -> IO (Maybe TvSubst) -improveRTTIType hsc_env ty rtti_ty = runTR_maybe hsc_env $ do - let (_,ty0) = splitForAllTys ty - ty_tvs = varSetElems $ tyVarsOfType ty0 - let (_,rtti_ty0)= splitForAllTys rtti_ty - rtti_tvs = varSetElems $ tyVarsOfType rtti_ty0 - (ty_tvs',_,ty')<- tcInstType (mapM tcInstTyVar) (mkSigmaTy ty_tvs [] ty0) - (_,_,rtti_ty') <- tcInstType (mapM tcInstTyVar) (mkSigmaTy rtti_tvs [] rtti_ty0) - boxyUnify rtti_ty' ty' - tvs1_contents <- zonkTcTyVars ty_tvs' - let subst = uncurry zipTopTvSubst - (unzip [(tv,ty) | tv <- ty_tvs, ty <- tvs1_contents - , getTyVar_maybe ty /= Just tv - , not(isTyVarTy ty)]) --- liftIO $ hPutStrLn stderr $ showSDocDebug $ text "unify " <+> sep [ppr ty, ppr rtti_ty, equals, ppr subst ] - return subst +improveRTTIType :: HscEnv -> RttiType -> RttiType -> Maybe TvSubst +improveRTTIType _ base_ty new_ty + = U.tcUnifyTys (const U.BindMe) [base_ty] [new_ty] + +getDataConArgTys :: DataCon -> Type -> TR [Type] +-- Given the result type ty of a constructor application (D a b c :: ty) +-- return the types of the arguments. This is RTTI-land, so 'ty' might +-- not be fully known. Moreover, the arg types might involve existentials; +-- if so, make up fresh RTTI type variables for them +getDataConArgTys dc con_app_ty + = do { (_, ex_tys, _) <- instTyVars ex_tvs + ; let rep_con_app_ty = repType con_app_ty + ; ty_args <- case tcSplitTyConApp_maybe rep_con_app_ty of + Just (tc, ty_args) | dataConTyCon dc == tc + -> ASSERT( univ_tvs `equalLength` ty_args) + return ty_args + _ -> do { (_, ty_args, subst) <- instTyVars univ_tvs + ; let res_ty = substTy subst (dataConOrigResTy dc) + ; addConstraint rep_con_app_ty res_ty + ; return ty_args } + -- It is necessary to check dataConTyCon dc == tc + -- because it may be the case that tc is a recursive + -- newtype and tcSplitTyConApp has not removed it. In + -- that case, we happily give up and don't match + ; let subst = zipTopTvSubst (univ_tvs ++ ex_tvs) (ty_args ++ ex_tys) + ; return (substTys subst (dataConRepArgTys dc)) } + where + univ_tvs = dataConUnivTyVars dc + ex_tvs = dataConExTyVars dc + +isPtrType :: Type -> Bool +isPtrType ty = case typePrimRep ty of + PtrRep -> True + _ -> False + +-- Soundness checks +-------------------- +{- +This is not formalized anywhere, so hold to your seats! +RTTI in the presence of newtypes can be a tricky and unsound business. + +Example: +~~~~~~~~~ +Suppose we are doing RTTI for a partially evaluated +closure t, the real type of which is t :: MkT Int, for + + newtype MkT a = MkT [Maybe a] + +The table below shows the results of RTTI and the improvement +calculated for different combinations of evaluatedness and :type t. +Regard the two first columns as input and the next two as output. + + # | t | :type t | rtti(t) | improv. | result + ------------------------------------------------------------ + 1 | _ | t b | a | none | OK + 2 | _ | MkT b | a | none | OK + 3 | _ | t Int | a | none | OK + + If t is not evaluated at *all*, we are safe. + + 4 | (_ : _) | t b | [a] | t = [] | UNSOUND + 5 | (_ : _) | MkT b | MkT a | none | OK (compensating for the missing newtype) + 6 | (_ : _) | t Int | [Int] | t = [] | UNSOUND + + If a is a minimal whnf, we run into trouble. Note that + row 5 above does newtype enrichment on the ty_rtty parameter. + + 7 | (Just _:_)| t b |[Maybe a] | t = [], | UNSOUND + | | | b = Maybe a| + + 8 | (Just _:_)| MkT b | MkT a | none | OK + 9 | (Just _:_)| t Int | FAIL | none | OK + + And if t is any more evaluated than whnf, we are still in trouble. + Because constraints are solved in top-down order, when we reach the + Maybe subterm what we got is already unsound. This explains why the + row 9 fails to complete. + + 10 | (Just _:_)| t Int | [Maybe a] | FAIL | OK + 11 | (Just 1:_)| t Int | [Maybe Int] | FAIL | OK + + We can undo the failure in row 9 by leaving out the constraint + coming from the type signature of t (i.e., the 2nd column). + Note that this type information is still used + to calculate the improvement. But we fail + when trying to calculate the improvement, as there is no unifier for + t Int = [Maybe a] or t Int = [Maybe Int]. + + + Another set of examples with t :: [MkT (Maybe Int)] \equiv [[Maybe (Maybe Int)]] + + # | t | :type t | rtti(t) | improvement | result + --------------------------------------------------------------------- + 1 |(Just _:_) | [t (Maybe a)] | [[Maybe b]] | t = [] | + | | | | b = Maybe a | + +The checks: +~~~~~~~~~~~ +Consider a function obtainType that takes a value and a type and produces +the Term representation and a substitution (the improvement). +Assume an auxiliar rtti' function which does the actual job if recovering +the type, but which may produce a false type. + +In pseudocode: + + rtti' :: a -> IO Type -- Does not use the static type information + + obtainType :: a -> Type -> IO (Maybe (Term, Improvement)) + obtainType v old_ty = do + rtti_ty <- rtti' v + if monomorphic rtti_ty || (check rtti_ty old_ty) + then ... + else return Nothing + where check rtti_ty old_ty = check1 rtti_ty && + check2 rtti_ty old_ty + + check1 :: Type -> Bool + check2 :: Type -> Type -> Bool + +Now, if rtti' returns a monomorphic type, we are safe. +If that is not the case, then we consider two conditions. + + +1. To prevent the class of unsoundness displayed by + rows 4 and 7 in the example: no higher kind tyvars + accepted. + + check1 (t a) = NO + check1 (t Int) = NO + check1 ([] a) = YES + +2. To prevent the class of unsoundness shown by row 6, + the rtti type should be structurally more + defined than the old type we are comparing it to. + check2 :: NewType -> OldType -> Bool + check2 a _ = True + check2 [a] a = True + check2 [a] (t Int) = False + check2 [a] (t a) = False -- By check1 we never reach this equation + check2 [Int] a = True + check2 [Int] (t Int) = True + check2 [Maybe a] (t Int) = False + check2 [Maybe Int] (t Int) = True + check2 (Maybe [a]) (m [Int]) = False + check2 (Maybe [Int]) (m [Int]) = True + +-} + +check1 :: QuantifiedType -> Bool +check1 (tvs, _) = not $ any isHigherKind (map tyVarKind tvs) + where + isHigherKind = not . null . fst . splitKindFunTys + +check2 :: QuantifiedType -> QuantifiedType -> Bool +check2 (_, rtti_ty) (_, old_ty) + | Just (_, rttis) <- tcSplitTyConApp_maybe rtti_ty + = case () of + _ | Just (_,olds) <- tcSplitTyConApp_maybe old_ty + -> and$ zipWith check2 (map quantifyType rttis) (map quantifyType olds) + _ | Just _ <- splitAppTy_maybe old_ty + -> isMonomorphicOnNonPhantomArgs rtti_ty + _ -> True + | otherwise = True -- Dealing with newtypes +-------------------------- {- congruenceNewtypes does a parallel fold over two Type values, compensating for missing newtypes on both sides. @@ -813,84 +1065,141 @@ Therefore, congruenceNewtypes is sound only if the types recovered by the RTTI mechanism are unified Top-Down. -} congruenceNewtypes :: TcType -> TcType -> TR (TcType,TcType) -congruenceNewtypes lhs rhs +congruenceNewtypes lhs rhs = go lhs rhs >>= \rhs' -> return (lhs,rhs') + where + go l r -- TyVar lhs inductive case - | Just tv <- getTyVar_maybe lhs - = recoverTc (return (lhs,rhs)) $ do + | Just tv <- getTyVar_maybe l + , isTcTyVar tv + , isMetaTyVar tv + = recoverTR (return r) $ do Indirect ty_v <- readMetaTyVar tv - (_lhs1, rhs1) <- congruenceNewtypes ty_v rhs - return (lhs, rhs1) + traceTR $ fsep [text "(congruence) Following indirect tyvar:", + ppr tv, equals, ppr ty_v] + go ty_v r -- FunTy inductive case - | Just (l1,l2) <- splitFunTy_maybe lhs - , Just (r1,r2) <- splitFunTy_maybe rhs - = do (l2',r2') <- congruenceNewtypes l2 r2 - (l1',r1') <- congruenceNewtypes l1 r1 - return (mkFunTy l1' l2', mkFunTy r1' r2') + | Just (l1,l2) <- splitFunTy_maybe l + , Just (r1,r2) <- splitFunTy_maybe r + = do r2' <- go l2 r2 + r1' <- go l1 r1 + return (mkFunTy r1' r2') -- TyconApp Inductive case; this is the interesting bit. - | Just (tycon_l, _) <- splitNewTyConApp_maybe lhs - , Just (tycon_r, _) <- splitNewTyConApp_maybe rhs + | Just (tycon_l, _) <- tcSplitTyConApp_maybe lhs + , Just (tycon_r, _) <- tcSplitTyConApp_maybe rhs , tycon_l /= tycon_r - = do rhs' <- upgrade tycon_l rhs - return (lhs, rhs') + = upgrade tycon_l r - | otherwise = return (lhs,rhs) + | otherwise = return r where upgrade :: TyCon -> Type -> TR Type upgrade new_tycon ty - | not (isNewTyCon new_tycon) = return ty - | otherwise = do - vars <- mapM (newVar . tyVarKind) (tyConTyVars new_tycon) + | not (isNewTyCon new_tycon) = do + traceTR (text "(Upgrade) Not matching newtype evidence: " <> + ppr new_tycon <> text " for " <> ppr ty) + return ty + | otherwise = do + traceTR (text "(Upgrade) upgraded " <> ppr ty <> + text " in presence of newtype evidence " <> ppr new_tycon) + (_, vars, _) <- instTyVars (tyConTyVars new_tycon) let ty' = mkTyConApp new_tycon vars - liftTcM (unifyType ty (repType ty')) + _ <- 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 +zonkTerm :: Term -> TcM Term +zonkTerm = foldTermM (TermFoldM + { fTermM = \ty dc v tt -> zonkRttiType ty >>= \ty' -> + return (Term ty' dc v tt) + , fSuspensionM = \ct ty v b -> zonkRttiType ty >>= \ty -> + return (Suspension ct ty v b) + , fNewtypeWrapM = \ty dc t -> zonkRttiType ty >>= \ty' -> + return$ NewtypeWrap ty' dc t + , fRefWrapM = \ty t -> return RefWrap `ap` + zonkRttiType ty `ap` return t + , fPrimM = (return.) . Prim }) + +zonkRttiType :: TcType -> TcM Type +-- Zonk the type, replacing any unbound Meta tyvars +-- by skolems, safely out of Meta-tyvar-land +zonkRttiType = zonkType (mkZonkTcTyVar zonk_unbound_meta) where - mapMif_ _ _ [] = [] - mapMif_ pred f (x:xx) = (if pred x then f x else return x) : mapMif_ pred f xx + zonk_unbound_meta tv + = ASSERT( isTcTyVar tv ) + do { tv' <- skolemiseUnboundMetaTyVar tv RuntimeUnk + -- This is where RuntimeUnks are born: + -- otherwise-unconstrained unification variables are + -- turned into RuntimeUnks as they leave the + -- typechecker's monad + ; return (mkTyVarTy tv') } + +-------------------------------------------------------------------------------- +-- Restore Class predicates out of a representation type +dictsView :: Type -> Type +-- dictsView ty = ty +dictsView (FunTy (TyConApp tc_dict args) ty) + | Just c <- tyConClass_maybe tc_dict + = FunTy (PredTy (ClassP c args)) (dictsView ty) +dictsView ty + | Just (tc_fun, [TyConApp tc_dict args, ty2]) <- tcSplitTyConApp_maybe ty + , Just c <- tyConClass_maybe tc_dict + = mkTyConApp tc_fun [PredTy (ClassP c args), dictsView ty2] +dictsView ty = ty + + +-- Use only for RTTI types +isMonomorphic :: RttiType -> Bool +isMonomorphic ty = noExistentials && noUniversals + where (tvs, _, ty') = tcSplitSigmaTy ty + noExistentials = isEmptyVarSet (tyVarsOfType ty') + noUniversals = null tvs + +-- Use only for RTTI types +isMonomorphicOnNonPhantomArgs :: RttiType -> Bool +isMonomorphicOnNonPhantomArgs ty + | Just (tc, all_args) <- tcSplitTyConApp_maybe (repType ty) + , phantom_vars <- tyConPhantomTyVars tc + , concrete_args <- [ arg | (tyv,arg) <- tyConTyVars tc `zip` all_args + , tyv `notElem` phantom_vars] + = all isMonomorphicOnNonPhantomArgs concrete_args + | Just (ty1, ty2) <- splitFunTy_maybe ty + = all isMonomorphicOnNonPhantomArgs [ty1,ty2] + | otherwise = isMonomorphic ty + +tyConPhantomTyVars :: TyCon -> [TyVar] +tyConPhantomTyVars tc + | isAlgTyCon tc + , Just dcs <- tyConDataCons_maybe tc + , dc_vars <- concatMap dataConUnivTyVars dcs + = tyConTyVars tc \\ dc_vars +tyConPhantomTyVars _ = [] + +type QuantifiedType = ([TyVar], Type) -- Make the free type variables explicit + +quantifyType :: Type -> QuantifiedType +-- Generalize the type: find all free tyvars and wrap in the appropiate ForAll. +quantifyType ty = (varSetElems (tyVarsOfType ty), ty) 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)) + = ASSERT2 (i < length(elems a), ppr(length$ elems a, i)) case indexArray# ptrs# i# of (# e #) -> f e -zonkTerm :: Term -> TcM Term -zonkTerm = foldTerm idTermFoldM { - fTerm = \ty dc v tt -> sequence tt >>= \tt -> - zonkTcType ty >>= \ty' -> - return (Term ty' dc v tt) - ,fSuspension = \ct ty v b -> zonkTcType ty >>= \ty -> - 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 - +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 +extractUnboxed :: [Type] -> Closure -> [[Word]] +extractUnboxed tt clos = go tt (nonPtrs clos) + where sizeofType t = primRepSizeW (typePrimRep t) + go [] _ = [] + go (t:tt) xx + | (x, rest) <- splitAt (sizeofType t) xx + = x : go tt rest