GlobalIdDetails(..), notGlobalId, -- Not abstract
IdInfo, -- Abstract
- vanillaIdInfo, noCafIdInfo, hasCafIdInfo,
+ vanillaIdInfo, noCafIdInfo,
seqIdInfo, megaSeqIdInfo,
-- Zapping
zapLamInfo, zapDemandInfo,
- shortableIdInfo, copyIdInfo,
-- Arity
ArityInfo,
-- 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,
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
import CoreSyn
-import Type ( Type, usOnce, eqUsage )
+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,
Activation(..)
)
import DataCon ( DataCon )
+import TyCon ( TyCon, FieldLabel )
import ForeignCall ( ForeignCall )
-import FieldLabel ( FieldLabel )
-import Type ( usOnce )
-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
`setWorkerInfo`,
`setLBVarInfo`,
`setOccInfo`,
- `setCgInfo`,
`setCafInfo`,
`setNewStrictnessInfo`,
`setAllStrictnessInfo`,
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
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}
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
megaSeqIdInfo :: IdInfo -> ()
megaSeqIdInfo info
- = seqRules (specInfo info) `seq`
+ = seqSpecInfo (specInfo info) `seq`
seqWorker (workerInfo info) `seq`
-- Omitting this improves runtimes a little, presumably because
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}
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 }
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 }
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,
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}
--
-- 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}
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
%* *
%************************************************************************
-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
| 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@}
%************************************************************************
If the @Id@ is a lambda-bound variable then it may have lambda-bound
-var info. The usage analysis (UsageSP) detects whether the lambda
-binding this var is a ``one-shot'' lambda; that is, whether it is
-applied at most once.
+var info. Sometimes we know whether the lambda binding this var is a
+``one-shot'' lambda; that is, whether it is applied at most once.
This information may be useful in optimisation, as computations may
safely be floated inside such a lambda without risk of duplicating
work.
\begin{code}
-data LBVarInfo
- = NoLBVarInfo
-
- | LBVarInfo Type -- The lambda that binds this Id has this usage
- -- annotation (i.e., if ==usOnce, then the
- -- lambda is applied at most once).
- -- The annotation's kind must be `$'
- -- HACK ALERT! placing this info here is a short-term hack,
- -- but it minimises changes to the rest of the compiler.
- -- Hack agreed by SLPJ/KSW 1999-04.
+data LBVarInfo = NoLBVarInfo
+ | IsOneShotLambda -- The lambda is applied at most once).
seqLBVar l = l `seq` ()
\end{code}
\begin{code}
-hasNoLBVarInfo NoLBVarInfo = True
-hasNoLBVarInfo other = False
+hasNoLBVarInfo NoLBVarInfo = True
+hasNoLBVarInfo IsOneShotLambda = False
noLBVarInfo = NoLBVarInfo
--- not safe to print or parse LBVarInfo because it is not really a
--- property of the definition, but a property of the context.
pprLBVarInfo NoLBVarInfo = empty
-pprLBVarInfo (LBVarInfo u) | u `eqUsage` usOnce
- = ptext SLIT("OneShot")
- | otherwise
- = empty
+pprLBVarInfo IsOneShotLambda = ptext SLIT("OneShot")
instance Outputable LBVarInfo where
ppr = pprLBVarInfo
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)
| 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}