%
+% (c) The University of Glasgow 2006
% (c) The Univserity of Glasgow 1992-2004
%
\begin{code}
module ClosureInfo (
- ClosureInfo, LambdaFormInfo, SMRep, -- all abstract
- StandardFormInfo,
+ ClosureInfo(..), LambdaFormInfo(..), -- would be abstract but
+ StandardFormInfo(..), -- mkCmmInfo looks inside
+ SMRep,
ArgDescr(..), Liveness(..),
C_SRT(..), needsSRT,
mkLFThunk, mkLFReEntrant, mkConLFInfo, mkSelectorLFInfo,
mkApLFInfo, mkLFImported, mkLFArgument, mkLFLetNoEscape,
- mkClosureInfo, mkConInfo,
+ mkClosureInfo, mkConInfo, maybeIsLFCon,
closureSize, closureNonHdrSize,
closureGoodStuffSize, closurePtrsSize,
closureNeedsUpdSpace, closureIsThunk,
closureSingleEntry, closureReEntrant, isConstrClosure_maybe,
closureFunInfo, isStandardFormThunk, isKnownFun,
+ funTag, funTagLFInfo, tagForArity,
enterIdLabel, enterLocalIdLabel, enterReturnPtLabel,
#include "../includes/MachDeps.h"
#include "HsVersions.h"
+--import CgUtils
import StgSyn
-import SMRep -- all of it
+import SMRep
import CLabel
-import Packages ( isDllName )
-import PackageConfig ( PackageId )
-import StaticFlags ( opt_SccProfilingOn, opt_OmitBlackHoling,
- opt_Parallel, opt_DoTickyProfiling )
-import Id ( Id, idType, idArity, idName )
-import DataCon ( DataCon, dataConTyCon, isNullaryRepDataCon, dataConName )
-import Name ( Name, nameUnique, getOccName, getOccString )
-import OccName ( occNameString )
-import Type ( isUnLiftedType, Type, repType, splitTyConApp_maybe )
-import TcType ( tcSplitSigmaTy )
-import TyCon ( isFunTyCon, isAbstractTyCon )
-import BasicTypes ( TopLevelFlag(..), isNotTopLevel, isTopLevel, ipNameName )
+import Packages
+import PackageConfig
+import StaticFlags
+import Id
+import DataCon
+import Name
+import OccName
+import Type
+import TypeRep
+import TcType
+import TyCon
+import BasicTypes
import FastString
import Outputable
import Constants
-
-import TypeRep -- TEMP
\end{code}
data C_SRT = NoC_SRT
| C_SRT !CLabel !WordOff !StgHalfWord {-bitmap or escape-}
+ deriving (Eq)
needsSRT :: C_SRT -> Bool
needsSRT NoC_SRT = False
needsSRT (C_SRT _ _ _) = True
+
+instance Outputable C_SRT where
+ ppr (NoC_SRT) = ptext SLIT("_no_srt_")
+ ppr (C_SRT label off bitmap) = parens (ppr label <> comma <> ppr off <> comma <> text (show bitmap))
\end{code}
%************************************************************************
data ArgDescr
= ArgSpec -- Fits one of the standard patterns
- !Int -- RTS type identifier ARG_P, ARG_N, ...
+ !StgHalfWord -- RTS type identifier ARG_P, ARG_N, ...
| ArgGen -- General case
Liveness -- Details about the arguments
(might_be_a_function thunk_ty)
might_be_a_function :: Type -> Bool
+-- Return False only if we are *sure* it's a data type
+-- Look through newtypes etc as much as poss
might_be_a_function ty
- | Just (tc,_) <- splitTyConApp_maybe (repType ty),
- not (isFunTyCon tc) && not (isAbstractTyCon tc) = False
- -- don't forget to check for abstract types, which might
- -- be functions too.
- | otherwise = True
+ = case splitTyConApp_maybe (repType ty) of
+ Just (tc, _) -> not (isDataTyCon tc)
+ Nothing -> True
\end{code}
@mkConLFInfo@ is similar, for constructors.
mkConLFInfo :: DataCon -> LambdaFormInfo
mkConLFInfo con = LFCon con
+maybeIsLFCon :: LambdaFormInfo -> Maybe DataCon
+maybeIsLFCon (LFCon con) = Just con
+maybeIsLFCon _ = Nothing
+
mkSelectorLFInfo id offset updatable
= LFThunk NotTopLevel False updatable (SelectorThunk offset)
(might_be_a_function (idType id))
ReturnCon con
getCallMethod this_pkg name (LFThunk _ _ updatable std_form_info is_fun) n_args
- | is_fun -- Must always "call" a function-typed
- = SlowCall -- thing, cannot just enter it [in eval/apply, the entry code
+ | is_fun -- *Might* be a function, so we must "call" it (which is always safe)
+ = SlowCall -- We cannot just enter it [in eval/apply, the entry code
-- is the fast-entry code]
+ -- Since is_fun is False, we are *definitely* looking at a data value
| updatable || opt_DoTickyProfiling -- to catch double entry
{- OLD: || opt_SMP
I decided to remove this, because in SMP mode it doesn't matter
if we enter the same thunk multiple times, so the optimisation
of jumping directly to the entry code is still valid. --SDM
-}
- = ASSERT( n_args == 0 ) EnterIt
+ = EnterIt
+ -- We used to have ASSERT( n_args == 0 ), but actually it is
+ -- possible for the optimiser to generate
+ -- let bot :: Int = error Int "urk"
+ -- in (bot `cast` unsafeCoerce Int (Int -> Int)) 3
+ -- This happens as a result of the case-of-error transformation
+ -- So the right thing to do is just to enter the thing
| otherwise -- Jump direct to code for single-entry thunks
= ASSERT( n_args == 0 )
isConstrClosure_maybe _ = Nothing
closureFunInfo :: ClosureInfo -> Maybe (Int, ArgDescr)
-closureFunInfo (ClosureInfo { closureLFInfo = LFReEntrant _ arity _ arg_desc})
- = Just (arity, arg_desc)
-closureFunInfo _
- = Nothing
+closureFunInfo (ClosureInfo { closureLFInfo = lf_info }) = lfFunInfo lf_info
+closureFunInfo _ = Nothing
+
+lfFunInfo :: LambdaFormInfo -> Maybe (Int, ArgDescr)
+lfFunInfo (LFReEntrant _ arity _ arg_desc) = Just (arity, arg_desc)
+lfFunInfo _ = Nothing
+
+funTag :: ClosureInfo -> Int
+funTag (ClosureInfo { closureLFInfo = lf_info }) = funTagLFInfo lf_info
+funTag _ = 0
+
+-- maybe this should do constructor tags too?
+funTagLFInfo :: LambdaFormInfo -> Int
+funTagLFInfo lf
+ -- A function is tagged with its arity
+ | Just (arity,_) <- lfFunInfo lf,
+ Just tag <- tagForArity arity
+ = tag
+
+ -- other closures (and unknown ones) are not tagged
+ | otherwise
+ = 0
+
+tagForArity :: Int -> Maybe Int
+tagForArity i | i <= mAX_PTR_TAG = Just i
+ | otherwise = Nothing
\end{code}
\begin{code}
getPredTyDescription (ClassP cl tys) = getOccString cl
getPredTyDescription (IParam ip ty) = getOccString (ipNameName ip)
\end{code}
-
-