\begin{code}
module IdInfo (
- -- * The GlobalIdDetails type
- GlobalIdDetails(..), notGlobalId, -- Not abstract
+ -- * The IdDetails type
+ IdDetails(..), pprIdDetails,
-- * The IdInfo type
IdInfo, -- Abstract
cprInfoFromNewStrictness,
#endif
- -- ** The WorkerInfo type
- WorkerInfo(..),
- workerExists, wrapperArity, workerId,
- workerInfo, setWorkerInfo, ppWorkerInfo,
-
-- ** Unfolding Info
unfoldingInfo, setUnfoldingInfo, setUnfoldingInfoLazily,
TickBoxOp(..), TickBoxId,
) where
-import {-# SOURCE #-} CoreSyn ( CoreRule, setRuleIdName, seqRules, Unfolding, noUnfolding )
+import CoreSyn ( CoreRule, setRuleIdName, seqRules, Unfolding, noUnfolding )
import Class
import PrimOp
import Name
-import Var
import VarSet
import BasicTypes
import DataCon
`setArityInfo`,
`setInlinePragInfo`,
`setUnfoldingInfo`,
- `setWorkerInfo`,
`setLBVarInfo`,
`setOccInfo`,
`setCafInfo`,
seqNewStrictnessInfo (Just ty) = seqStrictSig ty
pprNewStrictness :: Maybe StrictSig -> SDoc
-pprNewStrictness Nothing = empty
-pprNewStrictness (Just sig) = ftext (fsLit "Str:") <+> ppr sig
+pprNewStrictness Nothing = empty
+pprNewStrictness (Just sig) = ppr sig
#ifdef OLD_STRICTNESS
oldStrictnessFromNew :: StrictSig -> Demand.StrictnessInfo
%************************************************************************
%* *
-\subsection{GlobalIdDetails}
+ IdDetails
%* *
%************************************************************************
-This type is here (rather than in Id.lhs) mainly because there's
-an IdInfo.hi-boot, but no Id.hi-boot, and GlobalIdDetails is imported
-(recursively) by Var.lhs.
-
\begin{code}
--- | Information pertaining to global 'Id's. See "Var#globalvslocal" for the distinction
--- between global and local in this context
-data GlobalIdDetails
- = VanillaGlobal -- ^ The 'Id' is imported from elsewhere or is a default method 'Id'
+-- | The 'IdDetails' of an 'Id' give stable, and necessary,
+-- information about the Id.
+data IdDetails
+ = VanillaId
-- | The 'Id' for a record selector
- | RecordSelId
+ | RecSelId
{ sel_tycon :: TyCon -- ^ For a data type family, this is the /instance/ 'TyCon'
-- not the family 'TyCon'
- , sel_label :: FieldLabel
, sel_naughty :: Bool -- True <=> a "naughty" selector which can't actually exist, for example @x@ in:
- --
- -- > data T = forall a. MkT { x :: a }
- }
- -- See Note [Naughty record selectors]
- -- with MkId.mkRecordSelectorId
+ -- data T = forall a. MkT { x :: a }
+ } -- See Note [Naughty record selectors] in TcTyClsDecls
| DataConWorkId DataCon -- ^ The 'Id' is for a data constructor /worker/
| DataConWrapId DataCon -- ^ The 'Id' is for a data constructor /wrapper/
-- b) when desugaring a RecordCon we can get
-- from the Id back to the data con]
- | ClassOpId Class -- ^ The 'Id' is an operation of a class
+ | ClassOpId Class -- ^ The 'Id' is an superclass selector or class operation of a class
| PrimOpId PrimOp -- ^ The 'Id' is for a primitive operator
| FCallId ForeignCall -- ^ The 'Id' is for a foreign call
| TickBoxOpId TickBoxOp -- ^ The 'Id' is for a HPC tick box (both traditional and binary)
- | NotGlobalId -- ^ Used as a convenient extra return value from 'globalIdDetails'
-
--- | An entirely unhelpful 'GlobalIdDetails'
-notGlobalId :: GlobalIdDetails
-notGlobalId = NotGlobalId
-
-instance Outputable GlobalIdDetails where
- ppr NotGlobalId = ptext (sLit "[***NotGlobalId***]")
- ppr VanillaGlobal = ptext (sLit "[GlobalId]")
- 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 (TickBoxOpId _) = ptext (sLit "[TickBoxOp]")
- ppr (RecordSelId {}) = ptext (sLit "[RecSel]")
+ | DFunId Bool -- ^ A dictionary function.
+ -- True <=> the class has only one method, so may be
+ -- implemented with a newtype, so it might be bad
+ -- to be strict on this dictionary
+
+
+instance Outputable IdDetails where
+ ppr = pprIdDetails
+
+pprIdDetails :: IdDetails -> SDoc
+pprIdDetails VanillaId = empty
+pprIdDetails other = brackets (pp other)
+ where
+ pp VanillaId = panic "pprIdDetails"
+ pp (DataConWorkId _) = ptext (sLit "DataCon")
+ pp (DataConWrapId _) = ptext (sLit "DataConWrapper")
+ pp (ClassOpId {}) = ptext (sLit "ClassOp")
+ pp (PrimOpId _) = ptext (sLit "PrimOp")
+ pp (FCallId _) = ptext (sLit "ForeignCall")
+ pp (TickBoxOpId _) = ptext (sLit "TickBoxOp")
+ pp (DFunId b) = ptext (sLit "DFunId") <>
+ ppWhen b (ptext (sLit "(newtype)"))
+ pp (RecSelId { sel_naughty = is_naughty })
+ = brackets $ ptext (sLit "RecSel")
+ <> ppWhen is_naughty (ptext (sLit "(naughty)"))
\end{code}
= IdInfo {
arityInfo :: !ArityInfo, -- ^ 'Id' arity
specInfo :: SpecInfo, -- ^ Specialisations of the 'Id's function which exist
+ -- See Note [Specialisations and RULES in IdInfo]
#ifdef OLD_STRICTNESS
cprInfo :: CprInfo, -- ^ If the 'Id's function always constructs a product result
demandInfo :: Demand.Demand, -- ^ Whether or not the 'Id' is definitely demanded
strictnessInfo :: StrictnessInfo, -- ^ 'Id' 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'.
- -- However, when the module is imported by others, the
- -- '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, -- ^ The 'Id's unfolding
cafInfo :: CafInfo, -- ^ 'Id' CAF info
lbvarInfo :: LBVarInfo, -- ^ Info about a lambda-bound variable, if the 'Id' is one
- inlinePragInfo :: InlinePragInfo, -- ^ Any inline pragma atached to the 'Id'
+ inlinePragInfo :: InlinePragma, -- ^ Any inline pragma atached to the 'Id'
occInfo :: OccInfo, -- ^ How the 'Id' occurs in the program
newStrictnessInfo :: Maybe StrictSig, -- ^ Id strictness information. Reason for Maybe:
megaSeqIdInfo :: IdInfo -> ()
megaSeqIdInfo info
= seqSpecInfo (specInfo info) `seq`
- seqWorker (workerInfo info) `seq`
-- Omitting this improves runtimes a little, presumably because
-- some unfoldings are not calculated at all
Setters
\begin{code}
-setWorkerInfo :: IdInfo -> WorkerInfo -> IdInfo
-setWorkerInfo info wk = wk `seq` info { workerInfo = wk }
setSpecInfo :: IdInfo -> SpecInfo -> IdInfo
setSpecInfo info sp = sp `seq` info { specInfo = sp }
-setInlinePragInfo :: IdInfo -> InlinePragInfo -> IdInfo
+setInlinePragInfo :: IdInfo -> InlinePragma -> IdInfo
setInlinePragInfo info pr = pr `seq` info { inlinePragInfo = pr }
setOccInfo :: IdInfo -> OccInfo -> IdInfo
setOccInfo info oc = oc `seq` info { occInfo = oc }
strictnessInfo = NoStrictnessInfo,
#endif
specInfo = emptySpecInfo,
- workerInfo = NoWorker,
unfoldingInfo = noUnfolding,
lbvarInfo = NoLBVarInfo,
- inlinePragInfo = AlwaysActive,
+ inlinePragInfo = defaultInlinePragma,
occInfo = NoOccInfo,
newDemandInfo = Nothing,
newStrictnessInfo = Nothing
--
-- The default 'InlinePragInfo' is 'AlwaysActive', so the info serves
-- entirely as a way to inhibit inlining until we want it
-type InlinePragInfo = Activation
+type InlinePragInfo = InlinePragma
\end{code}
%* *
%************************************************************************
+Note [Specialisations and RULES in IdInfo]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Generally speaking, a GlobalIdshas an *empty* SpecInfo. All their
+RULES are contained in the globally-built rule-base. In principle,
+one could attach the to M.f the RULES for M.f that are defined in M.
+But we don't do that for instance declarations and so we just treat
+them all uniformly.
+
+The EXCEPTION is PrimOpIds, which do have rules in their IdInfo. That is
+jsut for convenience really.
+
+However, LocalIds may have non-empty SpecInfo. We treat them
+differently because:
+ a) they might be nested, in which case a global table won't work
+ b) the RULE might mention free variables, which we use to keep things alive
+
+In TidyPgm, when the LocalId becomes a GlobalId, its RULES are stripped off
+and put in the global list.
+
\begin{code}
-- | Records the specializations of this 'Id' that we know about
-- in the form of rewrite 'CoreRule's that target them
%************************************************************************
%* *
-\subsection[worker-IdInfo]{Worker info about an @Id@}
-%* *
-%************************************************************************
-
-There might not be a worker, even for a strict function, because:
-(a) the function might be small enough to inline, so no need
- for w/w split
-(b) the strictness info might be "SSS" or something, so no w/w split.
-
-Sometimes the arity of a wrapper changes from the original arity from
-which it was generated, so we always emit the "original" arity into
-the interface file, as part of the worker info.
-
-How can this happen? Sometimes we get
- f = coerce t (\x y -> $wf x y)
-at the moment of w/w split; but the eta reducer turns it into
- f = coerce t $wf
-which is perfectly fine except that the exposed arity so far as
-the code generator is concerned (zero) differs from the arity
-when we did the split (2).
-
-All this arises because we use 'arity' to mean "exactly how many
-top level lambdas are there" in interface files; but during the
-compilation of this module it means "how many things can I apply
-this to".
-
-\begin{code}
-
--- | If this Id has a worker then we store a reference to it. Worker
--- functions are generated by the worker/wrapper pass, using information
--- information from strictness analysis.
-data WorkerInfo = NoWorker -- ^ No known worker function
- | HasWorker Id Arity -- ^ The 'Arity' is the arity of the /wrapper/ at the moment of the
- -- worker/wrapper split, which may be different from the current 'Id' 'Aritiy'
-
-seqWorker :: WorkerInfo -> ()
-seqWorker (HasWorker id a) = id `seq` a `seq` ()
-seqWorker NoWorker = ()
-
-ppWorkerInfo :: WorkerInfo -> SDoc
-ppWorkerInfo NoWorker = empty
-ppWorkerInfo (HasWorker wk_id _) = ptext (sLit "Worker") <+> ppr wk_id
-
-workerExists :: WorkerInfo -> Bool
-workerExists NoWorker = False
-workerExists (HasWorker _ _) = True
-
--- | The 'Id' of the worker function if it exists, or a panic otherwise
-workerId :: WorkerInfo -> Id
-workerId (HasWorker id _) = id
-workerId NoWorker = panic "workerId: NoWorker"
-
--- | The 'Arity' of the worker function at the time of the split if it exists, or a panic otherwise
-wrapperArity :: WorkerInfo -> Arity
-wrapperArity (HasWorker _ a) = a
-wrapperArity NoWorker = panic "wrapperArity: NoWorker"
-\end{code}
-
-
-%************************************************************************
-%* *
\subsection[CG-IdInfo]{Code generator-related information}
%* *
%************************************************************************
| NoCafRefs -- ^ A function or static constructor
-- that refers to no CAFs.
+ deriving (Eq, Ord)
-- | Assumes that the 'Id' has CAF references: definitely safe
vanillaCafInfo :: CafInfo
seqCaf :: CafInfo -> ()
seqCaf c = c `seq` ()
+instance Outputable CafInfo where
+ ppr = ppCafInfo
+
ppCafInfo :: CafInfo -> SDoc
ppCafInfo NoCafRefs = ptext (sLit "NoCafRefs")
ppCafInfo MayHaveCafRefs = empty
| ReturnsCPR -- ^ Yes, this function returns a constructed product
-- Implicitly, this means "after the function has been applied
- -- to all its arguments", so the worker/wrapper builder in
+ -- to all its arguments", so the worker\/wrapper builder in
-- WwLib.mkWWcpr checks that that it is indeed saturated before
-- making use of the CPR info
-- ^ Zap info that depends on free variables
zapFragileInfo info
= Just (info `setSpecInfo` emptySpecInfo
- `setWorkerInfo` NoWorker
`setUnfoldingInfo` noUnfolding
`setOccInfo` if isFragileOcc occ then NoOccInfo else occ)
where