From 2c92736ea5a4aedf263a77d58c6e9b032a05b7ef Mon Sep 17 00:00:00 2001 From: Pepe Iborra Date: Sun, 10 Dec 2006 17:30:05 +0000 Subject: [PATCH] Playing with closures RtClosureInspect includes a bunch of stuff for playing with closures: - the datatype Closure is the low level representation type - the datatype Term is the high level representation type - cvObtainTerm is the main entry point, providing the Term representation of an arbitrary closure --- compiler/ghci/Linker.lhs | 14 +- compiler/ghci/RtClosureInspect.hs | 635 ++++++++++++++++++++++++++++++++ compiler/main/GHC.hs | 32 +- compiler/typecheck/TcRnDriver.lhs | 12 +- compiler/typecheck/TcRnDriver.lhs-boot | 5 + 5 files changed, 685 insertions(+), 13 deletions(-) create mode 100644 compiler/ghci/RtClosureInspect.hs create mode 100644 compiler/typecheck/TcRnDriver.lhs-boot diff --git a/compiler/ghci/Linker.lhs b/compiler/ghci/Linker.lhs index 6073d6f..640fc9d 100644 --- a/compiler/ghci/Linker.lhs +++ b/compiler/ghci/Linker.lhs @@ -14,11 +14,11 @@ necessary. \begin{code} {-# OPTIONS -optc-DNON_POSIX_SOURCE -#include "Linker.h" #-} -module Linker ( HValue, showLinkerState, +module Linker ( HValue, getHValue, showLinkerState, linkExpr, unload, extendLinkEnv, withExtendedLinkEnv, extendLoadedPkgs, - linkPackages,initDynLinker - ,recoverDataCon + linkPackages,initDynLinker, + recoverDataCon ) where #include "HsVersions.h" @@ -195,12 +195,14 @@ recoverDCInRTS a = do helper [] = Nothing helper x = Just . second (drop 1) . break (==delim) $ x in unfoldr helper - -removeLeadingUnderscore = if cLeadingUnderscore=="YES" + removeLeadingUnderscore = if cLeadingUnderscore=="YES" then tail else id - +getHValue :: Name -> IO (Maybe HValue) +getHValue name = do + pls <- readIORef v_PersistentLinkerState + return$ fmap snd (lookupNameEnv (closure_env pls) name) withExtendedLinkEnv :: [(Name,HValue)] -> IO a -> IO a withExtendedLinkEnv new_env action diff --git a/compiler/ghci/RtClosureInspect.hs b/compiler/ghci/RtClosureInspect.hs new file mode 100644 index 0000000..9161ae4 --- /dev/null +++ b/compiler/ghci/RtClosureInspect.hs @@ -0,0 +1,635 @@ +----------------------------------------------------------------------------- +-- +-- GHC Interactive support for inspecting arbitrary closures at runtime +-- +-- Pepe Iborra (supported by Google SoC) 2006 +-- +----------------------------------------------------------------------------- + +module RtClosureInspect( + + cvObtainTerm, -- :: HscEnv -> Bool -> Maybe Type -> HValue -> IO Term + + AddressEnv(..), + DataConEnv, + extendAddressEnvList, + extendAddressEnvList', + elemAddressEnv, + delFromAddressEnv, + emptyAddressEnv, + lookupAddressEnv, + + ClosureType(..), + getClosureData, + Closure ( tipe, infoTable, ptrs, nonPtrs ), + getClosureType, + isConstr, + isIndirection, + getInfoTablePtr, + + Term(..), + printTerm, + customPrintTerm, + customPrintTermBase, + termType, + foldTerm, + TermFold(..), + idTermFold, + idTermFoldM, + isFullyEvaluated, + isPointed, + isFullyEvaluatedTerm, +-- unsafeDeepSeq, + ) where + +#include "HsVersions.h" + +import ByteCodeItbls ( StgInfoTable ) +import qualified ByteCodeItbls as BCI( StgInfoTable(..) ) +import ByteCodeLink ( HValue ) +import HscTypes ( HscEnv ) + +import DataCon +import Type +import TcRnMonad +import TcType +import TcMType +import TcUnify +import TcGadt +import DriverPhases +import TyCon +import Var +import Name +import Unique +import UniqSupply +import Var ( setVarUnique, mkTyVar, tyVarKind, setTyVarKind ) +import VarEnv ( mkVarEnv ) +import OccName ( emptyTidyOccEnv ) +import VarSet ( VarSet, mkVarSet, varSetElems, unionVarSets ) +import Unique ( getUnique, incrUnique ) +import {-#SOURCE#-} TcRnDriver ( tcRnRecoverDataCon ) + +import TysPrim +import PrelNames +import TysWiredIn + +import Constants ( wORD_SIZE ) +import FastString ( mkFastString ) +import Outputable +import Panic + +import GHC.Arr ( Array(..) ) +import GHC.Ptr ( Ptr(..), castPtr ) +import GHC.Exts +import GHC.Int ( Int32(..), Int64(..) ) +import GHC.Word ( Word32(..), Word64(..) ) + +import Control.Monad ( liftM, liftM2, msum ) +import Data.Maybe +import Data.List +import Data.Traversable ( mapM ) +import Data.Array.Base +import Foreign.Storable +import Foreign ( unsafePerformIO ) + +import Prelude hiding ( mapM ) + +--------------------------------------------- +-- * A representation of semi evaluated Terms +--------------------------------------------- +{- + A few examples in this representation: + + > Just 10 = Term Data.Maybe Data.Maybe.Just (Just 10) [Term Int I# (10) "10"] + + > (('a',_,_),_,('b',_,_)) = + Term ((Char,b,c),d,(Char,e,f)) (,,) (('a',_,_),_,('b',_,_)) + [ Term (Char, b, c) (,,) ('a',_,_) [Term Char C# "a", Thunk, Thunk] + , Thunk + , Term (Char, e, f) (,,) ('b',_,_) [Term Char C# "b", Thunk, Thunk]] +-} + +data Term = Term { ty :: Type + , dc :: DataCon + , val :: HValue + , subTerms :: [Term] } + + | Prim { ty :: Type + , value :: String } + + | Suspension { ctype :: ClosureType + , mb_ty :: Maybe Type + , val :: HValue + , bound_to :: Maybe Name -- Useful for printing + } + +isTerm Term{} = True +isTerm _ = False +isSuspension Suspension{} = True +isSuspension _ = False +isPrim Prim{} = True +isPrim _ = False + +termType t@(Suspension {}) = mb_ty t +termType t = Just$ ty t + +instance Outputable (Term) where + ppr = head . customPrintTerm customPrintTermBase + +------------------------------------------------------------------------- +-- Runtime Closure Datatype and functions for retrieving closure related stuff +------------------------------------------------------------------------- +data ClosureType = Constr + | Fun + | Thunk Int + | ThunkSelector + | Blackhole + | AP + | PAP + | Indirection Int + | Other Int + deriving (Show, Eq) + +data Closure = Closure { tipe :: ClosureType + , infoTable :: StgInfoTable + , ptrs :: Array Int HValue + -- What would be the type here? HValue is ok? Should I build a Ptr? + , nonPtrs :: ByteArray# + } + +instance Outputable ClosureType where + ppr = text . show + +getInfoTablePtr :: a -> Ptr StgInfoTable +getInfoTablePtr x = + case infoPtr# x of + itbl_ptr -> castPtr ( Ptr itbl_ptr ) + +getClosureType :: a -> IO ClosureType +getClosureType = liftM (readCType . BCI.tipe ) . peek . getInfoTablePtr + +#include "../includes/ClosureTypes.h" + +aP_CODE = AP +pAP_CODE = PAP +#undef AP +#undef PAP + +getClosureData :: a -> IO Closure +getClosureData a = do + itbl <- peek (getInfoTablePtr a) + let tipe = readCType (BCI.tipe itbl) + case closurePayload# a of + (# ptrs, nptrs #) -> + let elems = BCI.ptrs itbl + ptrsList = Array 0 (fromIntegral$ elems) ptrs + in ptrsList `seq` return (Closure tipe itbl ptrsList nptrs) + +readCType :: Integral a => a -> ClosureType +readCType i + | i >= CONSTR && i <= CONSTR_NOCAF_STATIC = Constr + | i >= FUN && i <= FUN_STATIC = Fun + | i >= THUNK && i < THUNK_SELECTOR = Thunk (fromIntegral i) + | i == THUNK_SELECTOR = ThunkSelector + | i == BLACKHOLE = Blackhole + | i >= IND && i <= IND_STATIC = Indirection (fromIntegral i) + | fromIntegral i == aP_CODE = AP + | fromIntegral i == pAP_CODE = PAP + | otherwise = Other (fromIntegral i) + +isConstr, isIndirection :: ClosureType -> Bool +isConstr Constr = True +isConstr _ = False + +isIndirection (Indirection _) = True +--isIndirection ThunkSelector = True +isIndirection _ = False + +isFullyEvaluated :: a -> IO Bool +isFullyEvaluated a = do + closure <- getClosureData a + case tipe closure of + Constr -> do are_subs_evaluated <- amapM isFullyEvaluated (ptrs closure) + return$ and are_subs_evaluated + 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] + +-- 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 + | not (isConstr tipe) = seq a $! unsafeDeepSeq1 (i-1) a b + -- | unsafePerformIO (isFullyEvaluated a) = b + | otherwise = case unsafePerformIO (getClosureData a) of + closure -> foldl' (flip unsafeDeepSeq) b (ptrs closure) + where tipe = unsafePerformIO (getClosureType a) +-} +isPointed :: Type -> Bool +isPointed t | Just (t, _) <- splitTyConApp_maybe t = not$ isUnliftedTypeKind (tyConKind t) +isPointed _ = True + +#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) + +----------------------------------- +-- Boilerplate Fold code for Term +----------------------------------- + +data TermFold a = TermFold { fTerm :: Type -> DataCon -> HValue -> [a] -> a + , fPrim :: Type -> String -> a + , fSuspension :: ClosureType -> Maybe Type -> HValue -> Maybe Name -> a + } + +foldTerm :: TermFold a -> Term -> a +foldTerm tf (Term ty dc v tt) = fTerm tf ty dc v (map (foldTerm tf) tt) +foldTerm tf (Prim ty v ) = fPrim tf ty v +foldTerm tf (Suspension ct ty v b) = fSuspension tf ct ty v b + +idTermFold :: TermFold Term +idTermFold = TermFold { + fTerm = Term, + fPrim = Prim, + fSuspension = Suspension + } +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 + } + +---------------------------------- +-- Pretty printing of terms +---------------------------------- + +parensCond True = parens +parensCond False = id +app_prec::Int +app_prec = 10 + +printTerm :: Term -> SDoc +printTerm Prim{value=value} = text value +printTerm t@Term{} = printTerm1 0 t +printTerm Suspension{bound_to=Nothing} = char '_' -- <> ppr ct <> char '_' +printTerm Suspension{mb_ty=Just ty, bound_to=Just n} = + parens$ ppr n <> text "::" <> ppr ty + +printTerm1 p Term{dc=dc, subTerms=tt} +{- | dataConIsInfix dc, (t1:t2:tt') <- tt + = parens (printTerm1 True t1 <+> ppr dc <+> printTerm1 True ppr t2) + <+> hsep (map (printTerm1 True) tt) +-} + | null tt = ppr dc + | otherwise = parensCond (p > app_prec) + (ppr dc <+> sep (map (printTerm1 (app_prec+1)) tt)) + + where fixity = undefined + +printTerm1 _ t = printTerm t + +customPrintTerm :: Monad m => ((Int->Term->m SDoc)->[Term->m (Maybe SDoc)]) -> Term -> m SDoc +customPrintTerm custom = let +-- go :: Monad m => Int -> Term -> m SDoc + go prec t@Term{subTerms=tt, dc=dc} = do + mb_customDocs <- sequence$ sequence (custom go) t -- Inner sequence is List monad + case msum mb_customDocs of -- msum is in Maybe monad + Just doc -> return$ parensCond (prec>app_prec+1) doc +-- | dataConIsInfix dc, (t1:t2:tt') <- tt = + Nothing -> do pprSubterms <- mapM (go (app_prec+1)) tt + return$ parensCond (prec>app_prec+1) + (ppr dc <+> sep pprSubterms) + go _ t = return$ printTerm t + in go 0 + where fixity = undefined + +customPrintTermBase :: Monad m => (Int->Term-> m SDoc)->[Term->m (Maybe SDoc)] +customPrintTermBase showP = + [ + test isTupleDC (liftM (parens . cat . punctuate comma) . mapM (showP 0) . subTerms) + , test (isDC consDataCon) (\Term{subTerms=[h,t]} -> doList h t) + , test (isDC intDataCon) (coerceShow$ \(a::Int)->a) + , test (isDC charDataCon) (coerceShow$ \(a::Char)->a) +-- , test (isDC wordDataCon) (coerceShow$ \(a::Word)->a) + , test (isDC floatDataCon) (coerceShow$ \(a::Float)->a) + , test (isDC doubleDataCon) (coerceShow$ \(a::Double)->a) + , test isIntegerDC (coerceShow$ \(a::Integer)->a) + ] + where test pred f t = if pred t then liftM Just (f 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 + coerceShow f Term{val=val} = return . text . show . f . unsafeCoerce# $ val + --TODO pprinting of list terms is not lazy + doList h t = do + let elems = h : getListTerms t + isConsLast = isSuspension (last elems) && + (mb_ty$ last elems) /= (termType h) + init <- mapM (showP 0) (init elems) + last0 <- showP 0 (last elems) + let last = case length elems of + 1 -> last0 + _ | isConsLast -> text " | " <> last0 + _ -> comma <> last0 + return$ brackets (cat (punctuate comma init ++ [last])) + + where Just a /= Just b = not (a `coreEqType` b) + _ /= _ = True + getListTerms Term{subTerms=[h,t]} = h : getListTerms t + getListTerms t@Term{subTerms=[]} = [] + getListTerms t@Suspension{} = [t] + getListTerms t = pprPanic "getListTerms" (ppr t) + +isFullyEvaluatedTerm :: Term -> Bool +isFullyEvaluatedTerm Term {subTerms=tt} = all isFullyEvaluatedTerm tt +isFullyEvaluatedTerm Suspension {} = False +isFullyEvaluatedTerm Prim {} = True + + +----------------------------------- +-- Type Reconstruction +----------------------------------- + +-- The Type Reconstruction monad +type TR a = TcM a + +runTR :: HscEnv -> TR Term -> IO Term +runTR hsc_env c = do + mb_term <- initTcPrintErrors hsc_env iNTERACTIVE (c >>= zonkTerm) + case mb_term of + Nothing -> panic "Can't unify" + Just term -> return term + +trIO :: IO a -> TR a +trIO = liftTcM . ioToTcRn + +addConstraint :: TcType -> TcType -> TR () +addConstraint t1 t2 = congruenceNewtypes t1 t2 >> unifyType t1 t2 + +-- A parallel fold over a Type value, replacing +-- in the right side reptypes for newtypes as found in the lhs +-- Sadly it doesn't cover all the possibilities. It does not always manage +-- to recover the highest level type. See test print016 for an example +congruenceNewtypes :: TcType -> TcType -> TcM TcType +congruenceNewtypes lhs rhs +-- | pprTrace "Congruence" (ppr lhs $$ ppr rhs) False = undefined + -- We have a tctyvar at the other side + | Just tv <- getTyVar_maybe rhs +-- , trace "congruence, entering tyvar" True + = recoverM (return rhs) $ do + Indirect ty_v <- readMetaTyVar tv + newtyped_tytv <- congruenceNewtypes lhs ty_v + writeMutVar (metaTvRef tv) (Indirect newtyped_tytv) + return newtyped_tytv +-- We have a function type: go on inductively + | Just (r1,r2) <- splitFunTy_maybe rhs + , Just (l1,l2) <- splitFunTy_maybe lhs + = liftM2 mkFunTy ( congruenceNewtypes l1 r1) + (congruenceNewtypes l2 r2) +-- There is a newtype at the top level tycon and we can manage it + | Just (tycon, args) <- splitNewTyConApp_maybe lhs + , isNewTyCon tycon + , (tvs, realtipe) <- newTyConRep tycon + = case tcUnifyTys (const BindMe) [realtipe] [rhs] of + Just subst -> + let tvs' = substTys subst (map mkTyVarTy tvs) in + liftM (mkTyConApp tycon) (zipWithM congruenceNewtypes args tvs') + otherwise -> panic "congruenceNewtypes: Can't unify a newtype" + +-- We have a TyconApp: go on inductively + | Just (tycon, args) <- splitNewTyConApp_maybe lhs + , Just (tycon_v, args_v) <- splitNewTyConApp_maybe rhs + = liftM (mkTyConApp tycon_v) (zipWithM congruenceNewtypes args args_v) + + | otherwise = return rhs + + +newVar :: Kind -> TR TcTyVar +newVar = liftTcM . newFlexiTyVar + +liftTcM = id + +instScheme :: Type -> TR TcType +instScheme ty = liftTcM$ liftM trd (tcInstType (liftM fst3 . tcInstTyVars) ty) + where fst3 (x,y,z) = x + trd (x,y,z) = z + +cvObtainTerm :: HscEnv -> Bool -> Maybe Type -> HValue -> IO Term +cvObtainTerm hsc_env force mb_ty a = + -- Obtain the term and tidy the type before returning it + cvObtainTerm1 hsc_env force mb_ty a >>= return . tidyTypes + 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 + | Nothing <- mb_ty = runTR hsc_env . go argTypeKind $ hval + | Just ty <- mb_ty = runTR hsc_env $ do + term <- go argTypeKind hval + ty' <- instScheme ty + addConstraint ty' (fromMaybe (error "by definition") + (termType term)) + return term + where + go k a = do + ctype <- trIO$ getClosureType a + case ctype of +-- Thunks we may want to force + Thunk _ | force -> seq a $ go k a +-- We always follow indirections + _ | isIndirection ctype + -> do + clos <- trIO$ getClosureData a +-- dflags <- getSessionDynFlags session +-- debugTraceMsg dflags 2 (text "Following an indirection") + go k $! (ptrs clos ! 0) + -- The interesting case + Constr -> do + m_dc <- trIO$ tcRnRecoverDataCon hsc_env a + case m_dc of + Nothing -> panic "Can't find the DataCon for a term" + Just dc -> do + clos <- trIO$ getClosureData a + let extra_args = length(dataConRepArgTys dc) - length(dataConOrigArgTys dc) + subTtypes = drop extra_args (dataConRepArgTys dc) + (subTtypesP, subTtypesNP) = partition isPointed subTtypes + + subTermsP <- mapM (\i->extractSubterm i (ptrs clos) + (subTtypesP!!(i-extra_args))) + [extra_args..extra_args + length subTtypesP - 1] + let unboxeds = extractUnboxed subTtypesNP (nonPtrs clos) + subTermsNP = map (uncurry Prim) (zip subTtypesNP unboxeds) + subTerms = reOrderTerms subTermsP subTermsNP subTtypes + resType <- liftM mkTyVarTy (newVar k) + baseType <- instScheme (dataConRepType dc) + let myType = mkFunTys (map (fromMaybe undefined . termType) + subTerms) + resType + addConstraint baseType myType + return (Term resType dc a subTerms) +-- The otherwise case: can be a Thunk,AP,PAP,etc. + otherwise -> do + x <- liftM mkTyVarTy (newVar k) + return (Suspension ctype (Just x) a Nothing) + +-- 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 + extractSubterm (I# i#) ptrs ty = case ptrs of + (Array _ _ ptrs#) -> case indexArray# ptrs# i# of + (# e #) -> go (typeKind ty) e + +-- This is used to put together pointed and nonpointed subterms in the +-- correct order. + reOrderTerms _ _ [] = [] + reOrderTerms pointed unpointed (ty:tys) + | isPointed ty = head pointed : reOrderTerms (tail pointed) unpointed tys + | otherwise = head unpointed : reOrderTerms pointed (tail unpointed) tys + +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 -> mapM zonkTcType ty >>= \ty -> + return (Suspension ct ty v b)} + +{- +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 +-} + +-------------------------------------------------------------------- +-- The DataConEnv is used to store the addresses of datacons loaded +-- via the dynamic linker +-------------------------------------------------------------------- + +type DataConEnv = AddressEnv StgInfoTable + +-- Note that this AddressEnv and DataConEnv I wrote trying to follow +-- conventions in ghc, but probably they make no sense. Should +-- probably be replaced by a plain Data.Map + +newtype AddressEnv a = AE {outAE::[(Ptr a, Name)]} + +emptyAddressEnv = AE [] + +extendAddressEnvList :: AddressEnv a -> [(Ptr a, Name)] -> AddressEnv a +extendAddressEnvList' :: AddressEnv a -> [(Ptr a, Name)] -> AddressEnv a +elemAddressEnv :: Ptr a -> AddressEnv a -> Bool +delFromAddressEnv :: AddressEnv a -> Ptr a -> AddressEnv a +nullAddressEnv :: AddressEnv a -> Bool +lookupAddressEnv :: AddressEnv a -> Ptr a -> Maybe Name + +extendAddressEnvList (AE env) = AE . nub . (++ env) +extendAddressEnvList' (AE env) = AE . (++ env) +elemAddressEnv ptr (AE env) = ptr `elem` fst (unzip env) +delFromAddressEnv (AE env) ptr = AE [(ptr', n) | (ptr', n) <- env, ptr' /= ptr] +nullAddressEnv = null . outAE +lookupAddressEnv (AE env) = flip lookup env + +instance Outputable (AddressEnv a) where + ppr (AE ae) = vcat [text (show ptr) <> comma <> ppr a | (ptr,a) <- ae] + + diff --git a/compiler/main/GHC.hs b/compiler/main/GHC.hs index eabcafc..bd772fb 100644 --- a/compiler/main/GHC.hs +++ b/compiler/main/GHC.hs @@ -81,6 +81,8 @@ module GHC ( showModule, compileExpr, HValue, dynCompileExpr, lookupName, + + obtainTerm, #endif -- * Abstract syntax elements @@ -174,9 +176,6 @@ module GHC ( #include "HsVersions.h" #ifdef GHCI -import qualified Linker -import Data.Dynamic ( Dynamic ) -import Linker ( HValue, extendLinkEnv ) import TcRnDriver ( tcRnLookupRdrName, tcRnGetInfo, tcRnLookupName, getModuleExports ) import RdrName ( plusGlobalRdrEnv, Provenance(..), @@ -186,7 +185,25 @@ import HscMain ( hscParseIdentifier, hscStmt, hscTcExpr, hscKcType ) import Name ( nameOccName ) import Type ( tidyType ) import VarEnv ( emptyTidyEnv ) -import GHC.Exts ( unsafeCoerce# ) +import GHC.Exts ( unsafeCoerce# ) + +-- For breakpoints +import Breakpoints ( SiteNumber, Coord, nullBkptHandler, + BkptHandler(..), BkptLocation, noDbgSites ) +import Linker ( initDynLinker ) +import PrelNames ( breakpointJumpName, breakpointCondJumpName, + breakpointAutoJumpName ) + +import GHC.Exts ( Int(..), Ptr(..), int2Addr#, indexArray# ) +import GHC.Base ( Opaque(..) ) +import Foreign.StablePtr( deRefStablePtr, castPtrToStablePtr ) +import Foreign ( unsafePerformIO ) +import Data.Maybe ( fromMaybe) +import qualified Linker + +import Data.Dynamic ( Dynamic ) +import RtClosureInspect ( cvObtainTerm, Term ) +import Linker ( HValue, getHValue, extendLinkEnv ) #endif import Packages ( initPackages ) @@ -204,7 +221,7 @@ import Id ( Id, idType, isImplicitId, isDeadBinder, isPrimOpId, isFCallId, isClassOpId_maybe, isDataConWorkId, idDataCon, isBottomingId ) -import Var ( TyVar ) +import Var ( TyVar, varName ) import TysPrim ( alphaTyVars ) import TyCon ( TyCon, isClassTyCon, isSynTyCon, isNewTyCon, isPrimTyCon, isFunTyCon, isOpenTyCon, tyConArity, @@ -259,6 +276,7 @@ import System.Exit ( exitWith, ExitCode(..) ) import System.Time ( ClockTime ) import Control.Exception as Exception hiding (handle) import Data.IORef +import Data.Traversable ( traverse ) import System.IO import System.IO.Error ( isDoesNotExistError ) import Prelude hiding (init) @@ -2176,4 +2194,8 @@ showModule s mod_summary = withSession s $ \hsc_env -> do where obj_linkable = isObjectLinkable (expectJust "showModule" (hm_linkable mod_info)) +obtainTerm :: Session -> Bool -> Id -> IO (Maybe Term) +obtainTerm sess force id = withSession sess $ \hsc_env -> + getHValue (varName id) >>= traverse (cvObtainTerm hsc_env force Nothing) + #endif /* GHCI */ diff --git a/compiler/typecheck/TcRnDriver.lhs b/compiler/typecheck/TcRnDriver.lhs index 144d0d0..a93133d 100644 --- a/compiler/typecheck/TcRnDriver.lhs +++ b/compiler/typecheck/TcRnDriver.lhs @@ -12,6 +12,7 @@ module TcRnDriver ( tcRnLookupName, tcRnGetInfo, getModuleExports, + tcRnRecoverDataCon, #endif tcRnModule, tcTopSrcDecls, @@ -71,6 +72,8 @@ import HscTypes import Outputable #ifdef GHCI +import Linker +import DataCon import TcHsType import TcMType import TcMatches @@ -306,7 +309,7 @@ tcRnExtCore hsc_env (HsExtCore this_mod decls src_binds) mg_fix_env = emptyFixityEnv, mg_deprecs = NoDeprecs, mg_foreign = NoStubs, - mg_hpc_info = noHpcInfo + mg_hpc_info = noHpcInfo } } ; tcCoreDump mod_guts ; @@ -1136,6 +1139,12 @@ lookup_rdr_name rdr_name = do { return good_names } +tcRnRecoverDataCon :: HscEnv -> a -> IO (Maybe DataCon) +tcRnRecoverDataCon hsc_env a + = initTcPrintErrors hsc_env iNTERACTIVE $ + setInteractiveContext hsc_env (hsc_IC hsc_env) $ + do name <- recoverDataCon a + tcLookupDataCon name tcRnLookupName :: HscEnv -> Name -> IO (Maybe TyThing) tcRnLookupName hsc_env name @@ -1171,7 +1180,6 @@ tcRnGetInfo hsc_env name ispecs <- lookupInsts (icPrintUnqual ictxt) thing return (thing, fixity, ispecs) - lookupInsts :: PrintUnqualified -> TyThing -> TcM [Instance] -- Filter the instances by the ones whose tycons (or clases resp) -- are in scope unqualified. Otherwise we list a whole lot too many! diff --git a/compiler/typecheck/TcRnDriver.lhs-boot b/compiler/typecheck/TcRnDriver.lhs-boot new file mode 100644 index 0000000..0de156b --- /dev/null +++ b/compiler/typecheck/TcRnDriver.lhs-boot @@ -0,0 +1,5 @@ +>module TcRnDriver where +>import HscTypes +>import DataCon +> +>tcRnRecoverDataCon :: HscEnv -> a -> IO (Maybe DataCon) \ No newline at end of file -- 1.7.10.4