X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2FbasicTypes%2FIdInfo.lhs;h=d53bf5627d99638a48f0f07e57eb846b4e0dc65a;hb=28a464a75e14cece5db40f2765a29348273ff2d2;hp=7555cc2874a7d9e3b480ac1975c0e064cf75e294;hpb=957bf3756ffd56f5329a2aabe1022d6f996dd641;p=ghc-hetmet.git diff --git a/ghc/compiler/basicTypes/IdInfo.lhs b/ghc/compiler/basicTypes/IdInfo.lhs index 7555cc2..d53bf56 100644 --- a/ghc/compiler/basicTypes/IdInfo.lhs +++ b/ghc/compiler/basicTypes/IdInfo.lhs @@ -11,12 +11,11 @@ module IdInfo ( GlobalIdDetails(..), notGlobalId, -- Not abstract IdInfo, -- Abstract - vanillaIdInfo, noCafIdInfo, hasCafIdInfo, + vanillaIdInfo, noCafIdInfo, seqIdInfo, megaSeqIdInfo, -- Zapping zapLamInfo, zapDemandInfo, - shortableIdInfo, copyIdInfo, -- Arity ArityInfo, @@ -26,12 +25,14 @@ module IdInfo ( -- New demand and strictness info newStrictnessInfo, setNewStrictnessInfo, newDemandInfo, setNewDemandInfo, pprNewStrictness, + setAllStrictnessInfo, +#ifdef OLD_STRICTNESS -- Strictness; imported from Demand StrictnessInfo(..), mkStrictnessInfo, noStrictnessInfo, ppStrictnessInfo,isBottomingStrictness, - setAllStrictnessInfo, +#endif -- Worker WorkerInfo(..), workerExists, wrapperArity, workerId, @@ -62,15 +63,11 @@ module IdInfo ( occInfo, setOccInfo, -- Specialisation - specInfo, setSpecInfo, - - -- CG info - CgInfo(..), cgInfo, setCgInfo, pprCgInfo, - cgCafInfo, vanillaCgInfo, - CgInfoEnv, lookupCgInfo, + SpecInfo(..), specInfo, setSpecInfo, isEmptySpecInfo, + specInfoFreeVars, specInfoRules, seqSpecInfo, -- CAF info - CafInfo(..), ppCafInfo, setCafInfo, mayHaveCafRefs, + CafInfo(..), cafInfo, ppCafInfo, setCafInfo, mayHaveCafRefs, -- Lambda-bound variable info LBVarInfo(..), lbvarInfo, setLBVarInfo, noLBVarInfo, hasNoLBVarInfo @@ -80,11 +77,10 @@ module IdInfo ( import CoreSyn -import Type ( Type ) +import Class ( Class ) import PrimOp ( PrimOp ) -import NameEnv ( NameEnv, lookupNameEnv ) -import Name ( Name ) import Var ( Id ) +import VarSet ( VarSet, emptyVarSet, seqVarSet ) import BasicTypes ( OccInfo(..), isFragileOcc, isDeadOcc, seqOccInfo, isLoopBreaker, InsideLam, insideLam, notInsideLam, OneBranch, oneBranch, notOneBranch, @@ -92,14 +88,16 @@ import BasicTypes ( OccInfo(..), isFragileOcc, isDeadOcc, seqOccInfo, isLoopBrea Activation(..) ) import DataCon ( DataCon ) +import TyCon ( TyCon, FieldLabel ) import ForeignCall ( ForeignCall ) -import FieldLabel ( FieldLabel ) -import Demand hiding( Demand, seqDemand ) -import qualified Demand import NewDemand import Outputable import Maybe ( isJust ) + #ifdef OLD_STRICTNESS +import Name ( Name ) +import Demand hiding( Demand, seqDemand ) +import qualified Demand import Util ( listLengthCmp ) import List ( replicate ) #endif @@ -112,7 +110,6 @@ infixl 1 `setSpecInfo`, `setWorkerInfo`, `setLBVarInfo`, `setOccInfo`, - `setCgInfo`, `setCafInfo`, `setNewStrictnessInfo`, `setAllStrictnessInfo`, @@ -234,13 +231,21 @@ an IdInfo.hi-boot, but no Id.hi-boot, and GlobalIdDetails is imported data GlobalIdDetails = VanillaGlobal -- Imported from elsewhere, a default method Id. - | RecordSelId FieldLabel -- The Id for a record selector - | DataConId DataCon -- The Id for a data constructor *worker* + | RecordSelId -- The Id for a record selector + { sel_tycon :: TyCon + , sel_label :: FieldLabel + , sel_naughty :: Bool -- True <=> naughty + } -- See Note [Naughty record selectors] + -- with MkId.mkRecordSelectorId + + | DataConWorkId DataCon -- The Id for a data constructor *worker* | DataConWrapId DataCon -- The Id for a data constructor *wrapper* -- [the only reasons we need to know is so that - -- a) we can suppress printing a definition in the interface file - -- b) when typechecking a pattern we can get from the - -- Id back to the data con] + -- a) to support isImplicitId + -- b) when desugaring a RecordCon we can get + -- from the Id back to the data con] + + | ClassOpId Class -- An operation of a class | PrimOpId PrimOp -- The Id for a primitive operator | FCallId ForeignCall -- The Id for a foreign call @@ -252,11 +257,12 @@ notGlobalId = NotGlobalId instance Outputable GlobalIdDetails where ppr NotGlobalId = ptext SLIT("[***NotGlobalId***]") ppr VanillaGlobal = ptext SLIT("[GlobalId]") - ppr (DataConId _) = ptext SLIT("[DataCon]") + ppr (DataConWorkId _) = ptext SLIT("[DataCon]") ppr (DataConWrapId _) = ptext SLIT("[DataConWrapper]") + ppr (ClassOpId _) = ptext SLIT("[ClassOp]") ppr (PrimOpId _) = ptext SLIT("[PrimOp]") ppr (FCallId _) = ptext SLIT("[ForeignCall]") - ppr (RecordSelId _) = ptext SLIT("[RecSel]") + ppr (RecordSelId {}) = ptext SLIT("[RecSel]") \end{code} @@ -283,15 +289,22 @@ case. KSW 1999-04). data IdInfo = IdInfo { arityInfo :: !ArityInfo, -- Its arity - specInfo :: CoreRules, -- Specialisations of this function which exist + specInfo :: SpecInfo, -- Specialisations of this function which exist #ifdef OLD_STRICTNESS cprInfo :: CprInfo, -- Function always constructs a product result demandInfo :: Demand.Demand, -- Whether or not it is definitely demanded strictnessInfo :: StrictnessInfo, -- Strictness properties #endif workerInfo :: WorkerInfo, -- Pointer to Worker Function + -- Within one module this is irrelevant; the + -- inlining of a worker is handled via the Unfolding + -- WorkerInfo is used *only* to indicate the form of + -- the RHS, so that interface files don't actually + -- need to contain the RHS; it can be derived from + -- the strictness info + unfoldingInfo :: Unfolding, -- Its unfolding - cgInfo :: CgInfo, -- Code generator info (arity, CAF info) + cafInfo :: CafInfo, -- CAF info lbvarInfo :: LBVarInfo, -- Info about a lambda-bound variable inlinePragInfo :: InlinePragInfo, -- Inline pragma occInfo :: OccInfo, -- How it occurs @@ -311,7 +324,7 @@ seqIdInfo (IdInfo {}) = () megaSeqIdInfo :: IdInfo -> () megaSeqIdInfo info - = seqRules (specInfo info) `seq` + = seqSpecInfo (specInfo info) `seq` seqWorker (workerInfo info) `seq` -- Omitting this improves runtimes a little, presumably because @@ -327,10 +340,8 @@ megaSeqIdInfo info seqCpr (cprInfo info) `seq` #endif --- CgInfo is involved in a loop, so we have to be careful not to seq it --- too early. --- seqCg (cgInfo info) `seq` - seqLBVar (lbvarInfo info) `seq` + seqCaf (cafInfo info) `seq` + seqLBVar (lbvarInfo info) `seq` seqOccInfo (occInfo info) \end{code} @@ -351,19 +362,6 @@ setUnfoldingInfoLazily info uf -- Lazy variant to avoid looking at the info { unfoldingInfo = uf } -- (In this case the demand-zapping is redundant.) setUnfoldingInfo info uf - | isEvaldUnfolding uf - -- If the unfolding is a value, the demand info may - -- go pear-shaped, so we nuke it. Example: - -- let x = (a,b) in - -- case x of (p,q) -> h p q x - -- Here x is certainly demanded. But after we've nuked - -- the case, we'll get just - -- let x = (a,b) in h a b x - -- and now x is not demanded (I'm assuming h is lazy) - -- This really happens. The solution here is a bit ad hoc... - = info { unfoldingInfo = uf, newDemandInfo = Nothing } - - | otherwise -- We do *not* seq on the unfolding info, For some reason, doing so -- actually increases residency significantly. = info { unfoldingInfo = uf } @@ -373,8 +371,8 @@ setDemandInfo info dd = info { demandInfo = dd } setCprInfo info cp = info { cprInfo = cp } #endif -setArityInfo info ar = info { arityInfo = ar } -setCgInfo info cg = info { cgInfo = cg } +setArityInfo info ar = info { arityInfo = ar } +setCafInfo info caf = info { cafInfo = caf } setLBVarInfo info lb = {-lb `seq`-} info { lbvarInfo = lb } @@ -387,14 +385,14 @@ setNewStrictnessInfo info dd = dd `seq` info { newStrictnessInfo = dd } vanillaIdInfo :: IdInfo vanillaIdInfo = IdInfo { - cgInfo = noCgInfo, + cafInfo = vanillaCafInfo, arityInfo = unknownArity, #ifdef OLD_STRICTNESS cprInfo = NoCPRInfo, demandInfo = wwLazy, strictnessInfo = NoStrictnessInfo, #endif - specInfo = emptyCoreRules, + specInfo = emptySpecInfo, workerInfo = NoWorker, unfoldingInfo = noUnfolding, lbvarInfo = NoLBVarInfo, @@ -404,11 +402,8 @@ vanillaIdInfo newStrictnessInfo = Nothing } -hasCafIdInfo = vanillaIdInfo `setCgInfo` CgInfo MayHaveCafRefs -noCafIdInfo = vanillaIdInfo `setCgInfo` CgInfo NoCafRefs +noCafIdInfo = vanillaIdInfo `setCafInfo` NoCafRefs -- Used for built-in type Ids in MkId. - -- These must have a valid CgInfo set, so you can't - -- use vanillaIdInfo! \end{code} @@ -452,6 +447,36 @@ type InlinePragInfo = Activation -- -- If there was an INLINE pragma, then as a separate matter, the -- RHS will have been made to look small with a CoreSyn Inline Note + + -- The default InlinePragInfo is AlwaysActive, so the info serves + -- entirely as a way to inhibit inlining until we want it +\end{code} + + +%************************************************************************ +%* * + SpecInfo +%* * +%************************************************************************ + +\begin{code} +-- CoreRules is used only in an idSpecialisation (move to IdInfo?) +data SpecInfo + = SpecInfo [CoreRule] VarSet -- Locally-defined free vars of RHSs + +emptySpecInfo :: SpecInfo +emptySpecInfo = SpecInfo [] emptyVarSet + +isEmptySpecInfo :: SpecInfo -> Bool +isEmptySpecInfo (SpecInfo rs _) = null rs + +specInfoFreeVars :: SpecInfo -> VarSet +specInfoFreeVars (SpecInfo _ fvs) = fvs + +specInfoRules :: SpecInfo -> [CoreRule] +specInfoRules (SpecInfo rules _) = rules + +seqSpecInfo (SpecInfo rules fvs) = seqRules rules `seq` seqVarSet fvs \end{code} @@ -492,14 +517,14 @@ this to". data WorkerInfo = NoWorker | HasWorker Id Arity -- The Arity is the arity of the *wrapper* at the moment of the - -- w/w split. See comments in MkIface.ifaceId, with the 'Worker' code. + -- w/w split. See notes above. seqWorker :: WorkerInfo -> () seqWorker (HasWorker id a) = id `seq` a `seq` () seqWorker NoWorker = () ppWorkerInfo NoWorker = empty -ppWorkerInfo (HasWorker wk_id _) = ptext SLIT("__P") <+> ppr wk_id +ppWorkerInfo (HasWorker wk_id _) = ptext SLIT("Worker") <+> ppr wk_id workerExists :: WorkerInfo -> Bool workerExists NoWorker = False @@ -519,31 +544,7 @@ wrapperArity (HasWorker _ a) = a %* * %************************************************************************ -CgInfo encapsulates calling-convention information produced by the code -generator. It is pasted into the IdInfo of each emitted Id by CoreTidy, -but only as a thunk --- the information is only actually produced further -downstream, by the code generator. - \begin{code} -#ifndef OLD_STRICTNESS -newtype CgInfo = CgInfo CafInfo -- We are back to only having CafRefs in CgInfo -noCgInfo = panic "NoCgInfo!" -#else -data CgInfo = CgInfo CafInfo - | NoCgInfo -- In debug mode we don't want a black hole here - -- See Id.idCgInfo - -- noCgInfo is used for local Ids, which shouldn't need any CgInfo -noCgInfo = NoCgInfo -#endif - -cgCafInfo (CgInfo caf_info) = caf_info - -setCafInfo info caf_info = info `setCgInfo` CgInfo caf_info - -seqCg c = c `seq` () -- fields are strict anyhow - -vanillaCgInfo = CgInfo MayHaveCafRefs -- Definitely safe - -- CafInfo is used to build Static Reference Tables (see simplStg/SRT.lhs). data CafInfo @@ -555,30 +556,17 @@ data CafInfo | NoCafRefs -- A function or static constructor -- that refers to no CAFs. +vanillaCafInfo = MayHaveCafRefs -- Definitely safe + mayHaveCafRefs MayHaveCafRefs = True mayHaveCafRefs _ = False seqCaf c = c `seq` () -pprCgInfo (CgInfo caf_info) = ppCafInfo caf_info - -ppArity 0 = empty -ppArity n = hsep [ptext SLIT("__A"), int n] - -ppCafInfo NoCafRefs = ptext SLIT("__C") +ppCafInfo NoCafRefs = ptext SLIT("NoCafRefs") ppCafInfo MayHaveCafRefs = empty \end{code} -\begin{code} -type CgInfoEnv = NameEnv CgInfo - -lookupCgInfo :: NameEnv CgInfo -> Name -> CgInfo -lookupCgInfo env n = case lookupNameEnv env n of - Just info -> info - Nothing -> pprTrace "Urk! Not in CgInfo env" (ppr n) vanillaCgInfo -\end{code} - - %************************************************************************ %* * \subsection[cpr-IdInfo]{Constructed Product Result info about an @Id@} @@ -691,12 +679,12 @@ zapLamInfo info@(IdInfo {occInfo = occ, newDemandInfo = demand}) where -- The "unsafe" occ info is the ones that say I'm not in a lambda -- because that might not be true for an unsaturated lambda - is_safe_occ (OneOcc in_lam once) = in_lam - is_safe_occ other = True + is_safe_occ (OneOcc in_lam _ _) = in_lam + is_safe_occ other = True safe_occ = case occ of - OneOcc _ once -> OneOcc insideLam once - other -> occ + OneOcc _ once int_cxt -> OneOcc insideLam once int_cxt + other -> occ is_safe_dmd Nothing = True is_safe_dmd (Just dmd) = not (isStrictDmd dmd) @@ -709,70 +697,3 @@ zapDemandInfo info@(IdInfo {newDemandInfo = dmd}) | otherwise = Nothing \end{code} - -copyIdInfo is used when shorting out a top-level binding - f_local = BIG - f = f_local -where f is exported. We are going to swizzle it around to - f = BIG - f_local = f - -BUT (a) we must be careful about messing up rules - (b) we must ensure f's IdInfo ends up right - -(a) Messing up the rules -~~~~~~~~~~~~~~~~~~~~ -The example that went bad on me was this one: - - iterate :: (a -> a) -> a -> [a] - iterate = iterateList - - iterateFB c f x = x `c` iterateFB c f (f x) - iterateList f x = x : iterateList f (f x) - - {-# RULES - "iterate" forall f x. iterate f x = build (\c _n -> iterateFB c f x) - "iterateFB" iterateFB (:) = iterateList - #-} - -This got shorted out to: - - iterateList :: (a -> a) -> a -> [a] - iterateList = iterate - - iterateFB c f x = x `c` iterateFB c f (f x) - iterate f x = x : iterate f (f x) - - {-# RULES - "iterate" forall f x. iterate f x = build (\c _n -> iterateFB c f x) - "iterateFB" iterateFB (:) = iterate - #-} - -And now we get an infinite loop in the rule system - iterate f x -> build (\cn -> iterateFB c f x) - -> iterateFB (:) f x - -> iterate f x - -Tiresome solution: don't do shorting out if f has rewrite rules. -Hence shortableIdInfo. - -(b) Keeping the IdInfo right -~~~~~~~~~~~~~~~~~~~~~~~~ -We want to move strictness/worker info from f_local to f, but keep the rest. -Hence copyIdInfo. - -\begin{code} -shortableIdInfo :: IdInfo -> Bool -shortableIdInfo info = isEmptyCoreRules (specInfo info) - -copyIdInfo :: IdInfo -- f_local - -> IdInfo -- f (the exported one) - -> IdInfo -- New info for f -copyIdInfo f_local f = f { newStrictnessInfo = newStrictnessInfo f_local, -#ifdef OLD_STRICTNESS - strictnessInfo = strictnessInfo f_local, - cprInfo = cprInfo f_local, -#endif - workerInfo = workerInfo f_local - } -\end{code}