\begin{code}
module CoreSyn (
- Expr(..), Alt, Bind(..), Arg(..), Note(..),
+ Expr(..), Alt, Bind(..), AltCon(..), Arg, Note(..),
CoreExpr, CoreAlt, CoreBind, CoreArg, CoreBndr,
TaggedExpr, TaggedAlt, TaggedBind, TaggedArg,
- mkLets, mkLams,
+ mkLets, mkLams,
mkApps, mkTyApps, mkValApps, mkVarApps,
- mkLit, mkStringLit, mkStringLitFS, mkConApp, mkPrimApp, mkNote,
- bindNonRec, mkIfThenElse, varToCoreExpr,
+ mkLit, mkIntLitInt, mkIntLit,
+ mkConApp,
+ varToCoreExpr,
- bindersOf, bindersOfBinds, rhssOfBind, rhssOfAlts, isDeadBinder, isTyVar, isId,
+ isTyVar, isId,
+ bindersOf, bindersOfBinds, rhssOfBind, rhssOfAlts,
collectBinders, collectTyBinders, collectValBinders, collectTyAndValBinders,
collectArgs, collectBindersIgnoringNotes,
coreExprCc,
isValArg, isTypeArg, valArgCount, valBndrCount,
- -- Seq stuff
- seqRules, seqExpr, seqExprs,
+ -- Unfoldings
+ Unfolding(..), UnfoldingGuidance(..), -- Both abstract everywhere but in CoreUnfold.lhs
+ noUnfolding, mkOtherCon,
+ unfoldingTemplate, maybeUnfoldingTemplate, otherCons,
+ isValueUnfolding, isEvaldUnfolding, isCheapUnfolding, isCompulsoryUnfolding,
+ hasUnfolding, hasSomeUnfolding, neverUnfold,
- -- Size
- coreBindsSize,
+ -- Seq stuff
+ seqRules, seqExpr, seqExprs, seqUnfolding,
-- Annotated expressions
- AnnExpr, AnnExpr'(..), AnnBind(..), AnnAlt, deAnnotate,
+ AnnExpr, AnnExpr'(..), AnnBind(..), AnnAlt,
+ deAnnotate, deAnnotate', deAnnAlt,
-- Core rules
CoreRules(..), -- Representation needed by friends
CoreRule(..), -- CoreSubst, CoreTidy, CoreFVs, PprCore only
+ IdCoreRule,
RuleName,
- emptyCoreRules, isEmptyCoreRules, rulesRhsFreeVars, rulesRules
+ emptyCoreRules, isEmptyCoreRules, rulesRhsFreeVars, rulesRules,
+ isBuiltinRule
) where
#include "HsVersions.h"
-import TysWiredIn ( boolTy, stringTy, nilDataCon )
-import CostCentre ( CostCentre, isDupdCC, noCostCentre )
-import Var ( Var, Id, TyVar, IdOrTyVar, isTyVar, isId, idType )
-import VarEnv
-import Id ( mkWildId, getIdOccInfo, idInfo )
-import Type ( Type, UsageAnn, mkTyVarTy, isUnLiftedType, seqType )
-import IdInfo ( OccInfo(..), megaSeqIdInfo )
-import Const ( Con(..), DataCon, Literal(MachStr), mkMachInt, PrimOp )
-import TysWiredIn ( trueDataCon, falseDataCon )
-import ThinAir ( unpackCStringId, unpackCString2Id, addr2IntegerId )
+import CostCentre ( CostCentre, noCostCentre )
+import Var ( Var, Id, TyVar, isTyVar, isId )
+import Type ( Type, mkTyVarTy, seqType )
+import Literal ( Literal, mkMachInt )
+import DataCon ( DataCon, dataConId )
import VarSet
import Outputable
\end{code}
data Expr b -- "b" for the type of binders,
= Var Id
- | Con Con [Arg b] -- Guaranteed saturated
- -- The Con can be a DataCon, Literal, PrimOP
- -- but cannot be DEFAULT
+ | Lit Literal
| App (Expr b) (Arg b)
| Lam b (Expr b)
| Let (Bind b) (Expr b)
type Arg b = Expr b -- Can be a Type
-type Alt b = (Con, [b], Expr b)
- -- (DEFAULT, [], rhs) is the default alternative
- -- The Con can be a Literal, DataCon, or DEFAULT, but cannot be PrimOp
+type Alt b = (AltCon, [b], Expr b) -- (DEFAULT, [], rhs) is the default alternative
+
+data AltCon = DataAlt DataCon
+ | LitAlt Literal
+ | DEFAULT
+ deriving (Eq, Ord)
data Bind b = NonRec b (Expr b)
| Rec [(b, (Expr b))]
| InlineMe -- Instructs simplifer to treat the enclosed expression
-- as very small, and inline it at its call sites
-
- | TermUsg -- A term-level usage annotation
- UsageAnn -- (should not be a variable except during UsageSP inference)
\end{code}
\begin{code}
data CoreRules
= Rules [CoreRule]
- IdOrTyVarSet -- Locally-defined free vars of RHSs
+ VarSet -- Locally-defined free vars of RHSs
+
+emptyCoreRules :: CoreRules
+emptyCoreRules = Rules [] emptyVarSet
+
+isEmptyCoreRules :: CoreRules -> Bool
+isEmptyCoreRules (Rules rs _) = null rs
+rulesRhsFreeVars :: CoreRules -> VarSet
+rulesRhsFreeVars (Rules _ fvs) = fvs
+
+rulesRules :: CoreRules -> [CoreRule]
+rulesRules (Rules rules _) = rules
+\end{code}
+
+\begin{code}
type RuleName = FAST_STRING
+type IdCoreRule = (Id,CoreRule) -- Rules don't have their leading Id inside them
data CoreRule
= Rule RuleName
-- and suchlike. It has no free variables.
([CoreExpr] -> Maybe (RuleName, CoreExpr))
-emptyCoreRules :: CoreRules
-emptyCoreRules = Rules [] emptyVarSet
+isBuiltinRule (BuiltinRule _) = True
+isBuiltinRule _ = False
+\end{code}
-isEmptyCoreRules :: CoreRules -> Bool
-isEmptyCoreRules (Rules rs _) = null rs
-rulesRhsFreeVars :: CoreRules -> IdOrTyVarSet
-rulesRhsFreeVars (Rules _ fvs) = fvs
+%************************************************************************
+%* *
+\subsection{@Unfolding@ type}
+%* *
+%************************************************************************
-rulesRules :: CoreRules -> [CoreRule]
-rulesRules (Rules rules _) = rules
+The @Unfolding@ type is declared here to avoid numerous loops, but it
+should be abstract everywhere except in CoreUnfold.lhs
+
+\begin{code}
+data Unfolding
+ = NoUnfolding
+
+ | OtherCon [AltCon] -- It ain't one of these
+ -- (OtherCon xs) also indicates that something has been evaluated
+ -- and hence there's no point in re-evaluating it.
+ -- OtherCon [] is used even for non-data-type values
+ -- to indicated evaluated-ness. Notably:
+ -- data C = C !(Int -> Int)
+ -- case x of { C f -> ... }
+ -- Here, f gets an OtherCon [] unfolding.
+
+ | CompulsoryUnfolding CoreExpr -- There is no "original" definition,
+ -- so you'd better unfold.
+
+ | CoreUnfolding -- An unfolding with redundant cached information
+ CoreExpr -- Template; binder-info is correct
+ Bool -- True <=> top level binding
+ Bool -- exprIsValue template (cached); it is ok to discard a `seq` on
+ -- this variable
+ Bool -- True <=> doesn't waste (much) work to expand inside an inlining
+ -- Basically it's exprIsCheap
+ UnfoldingGuidance -- Tells about the *size* of the template.
+
+
+data UnfoldingGuidance
+ = UnfoldNever
+ | UnfoldIfGoodArgs Int -- and "n" value args
+
+ [Int] -- Discount if the argument is evaluated.
+ -- (i.e., a simplification will definitely
+ -- be possible). One elt of the list per *value* arg.
+
+ Int -- The "size" of the unfolding; to be elaborated
+ -- later. ToDo
+
+ Int -- Scrutinee discount: the discount to substract if the thing is in
+ -- a context (case (thing args) of ...),
+ -- (where there are the right number of arguments.)
+
+noUnfolding = NoUnfolding
+mkOtherCon = OtherCon
+
+seqUnfolding :: Unfolding -> ()
+seqUnfolding (CoreUnfolding e top b1 b2 g)
+ = seqExpr e `seq` top `seq` b1 `seq` b2 `seq` seqGuidance g
+seqUnfolding other = ()
+
+seqGuidance (UnfoldIfGoodArgs n ns a b) = n `seq` sum ns `seq` a `seq` b `seq` ()
+seqGuidance other = ()
+\end{code}
+
+\begin{code}
+unfoldingTemplate :: Unfolding -> CoreExpr
+unfoldingTemplate (CoreUnfolding expr _ _ _ _) = expr
+unfoldingTemplate (CompulsoryUnfolding expr) = expr
+unfoldingTemplate other = panic "getUnfoldingTemplate"
+
+maybeUnfoldingTemplate :: Unfolding -> Maybe CoreExpr
+maybeUnfoldingTemplate (CoreUnfolding expr _ _ _ _) = Just expr
+maybeUnfoldingTemplate (CompulsoryUnfolding expr) = Just expr
+maybeUnfoldingTemplate other = Nothing
+
+otherCons :: Unfolding -> [AltCon]
+otherCons (OtherCon cons) = cons
+otherCons other = []
+
+isValueUnfolding :: Unfolding -> Bool
+ -- Returns False for OtherCon
+isValueUnfolding (CoreUnfolding _ _ is_evald _ _) = is_evald
+isValueUnfolding other = False
+
+isEvaldUnfolding :: Unfolding -> Bool
+ -- Returns True for OtherCon
+isEvaldUnfolding (OtherCon _) = True
+isEvaldUnfolding (CoreUnfolding _ _ is_evald _ _) = is_evald
+isEvaldUnfolding other = False
+
+isCheapUnfolding :: Unfolding -> Bool
+isCheapUnfolding (CoreUnfolding _ _ _ is_cheap _) = is_cheap
+isCheapUnfolding other = False
+
+isCompulsoryUnfolding :: Unfolding -> Bool
+isCompulsoryUnfolding (CompulsoryUnfolding _) = True
+isCompulsoryUnfolding other = False
+
+hasUnfolding :: Unfolding -> Bool
+hasUnfolding (CoreUnfolding _ _ _ _ _) = True
+hasUnfolding (CompulsoryUnfolding _) = True
+hasUnfolding other = False
+
+hasSomeUnfolding :: Unfolding -> Bool
+hasSomeUnfolding NoUnfolding = False
+hasSomeUnfolding other = True
+
+neverUnfold :: Unfolding -> Bool
+neverUnfold NoUnfolding = True
+neverUnfold (OtherCon _) = True
+neverUnfold (CoreUnfolding _ _ _ _ UnfoldNever) = True
+neverUnfold other = False
+\end{code}
+
+
+%************************************************************************
+%* *
+\subsection{The main data type}
+%* *
+%************************************************************************
+
+\begin{code}
+-- The Ord is needed for the FiniteMap used in the lookForConstructor
+-- in SimplEnv. If you declared that lookForConstructor *ignores*
+-- constructor-applications with LitArg args, then you could get
+-- rid of this Ord.
+
+instance Outputable AltCon where
+ ppr (DataAlt dc) = ppr dc
+ ppr (LitAlt lit) = ppr lit
+ ppr DEFAULT = ptext SLIT("__DEFAULT")
+
+instance Show AltCon where
+ showsPrec p con = showsPrecSDoc p (ppr con)
\end{code}
The common case
\begin{code}
-type CoreBndr = IdOrTyVar
+type CoreBndr = Var
type CoreExpr = Expr CoreBndr
type CoreArg = Arg CoreBndr
type CoreBind = Bind CoreBndr
type CoreAlt = Alt CoreBndr
-type CoreNote = Note
\end{code}
Binders are ``tagged'' with a \tr{t}:
mkApps :: Expr b -> [Arg b] -> Expr b
mkTyApps :: Expr b -> [Type] -> Expr b
mkValApps :: Expr b -> [Expr b] -> Expr b
-mkVarApps :: CoreExpr -> [IdOrTyVar] -> CoreExpr
+mkVarApps :: Expr b -> [Var] -> Expr b
mkApps f args = foldl App f args
mkTyApps f args = foldl (\ e a -> App e (Type a)) f args
mkVarApps f vars = foldl (\ e a -> App e (varToCoreExpr a)) f vars
mkLit :: Literal -> Expr b
-mkStringLit :: String -> Expr b
-mkStringLitFS :: FAST_STRING -> Expr b
+mkIntLit :: Integer -> Expr b
+mkIntLitInt :: Int -> Expr b
mkConApp :: DataCon -> [Arg b] -> Expr b
-mkPrimApp :: PrimOp -> [Arg b] -> Expr b
+mkLets :: [Bind b] -> Expr b -> Expr b
+mkLams :: [b] -> Expr b -> Expr b
-mkLit lit = Con (Literal lit) []
-mkConApp con args = Con (DataCon con) args
-mkPrimApp op args = Con (PrimOp op) args
+mkLit lit = Lit lit
+mkConApp con args = mkApps (Var (dataConId con)) args
-mkStringLit str = mkStringLitFS (_PK_ str)
-
-mkStringLitFS str
- | any is_NUL (_UNPK_ str)
- = -- Must cater for NULs in literal string
- mkApps (Var unpackCString2Id)
- [mkLit (MachStr str),
- mkLit (mkMachInt (toInteger (_LENGTH_ str)))]
+mkLams binders body = foldr Lam body binders
+mkLets binds body = foldr Let body binds
- | otherwise
- = -- No NULs in the string
- App (Var unpackCStringId) (mkLit (MachStr str))
+mkIntLit n = Lit (mkMachInt n)
+mkIntLitInt n = Lit (mkMachInt (toInteger n))
- where
- is_NUL c = c == '\0'
-
-varToCoreExpr :: CoreBndr -> CoreExpr
+varToCoreExpr :: CoreBndr -> Expr b
varToCoreExpr v | isId v = Var v
| otherwise = Type (mkTyVarTy v)
\end{code}
-\begin{code}
-mkLams :: [b] -> Expr b -> Expr b
-mkLams binders body = foldr Lam body binders
-\end{code}
-
-\begin{code}
-mkLets :: [Bind b] -> Expr b -> Expr b
-mkLets binds body = foldr Let body binds
-
-bindNonRec :: Id -> CoreExpr -> CoreExpr -> CoreExpr
--- (bindNonRec x r b) produces either
--- let x = r in b
--- or
--- case r of x { _DEFAULT_ -> b }
---
--- depending on whether x is unlifted or not
--- It's used by the desugarer to avoid building bindings
--- that give Core Lint a heart attack. Actually the simplifier
--- deals with them perfectly well.
-bindNonRec bndr rhs body
- | isUnLiftedType (idType bndr) = Case rhs bndr [(DEFAULT,[],body)]
- | otherwise = Let (NonRec bndr rhs) body
-
-mkIfThenElse :: CoreExpr -> CoreExpr -> CoreExpr -> CoreExpr
-mkIfThenElse guard then_expr else_expr
- = Case guard (mkWildId boolTy)
- [ (DataCon trueDataCon, [], then_expr),
- (DataCon falseDataCon, [], else_expr) ]
-\end{code}
-
-mkNote removes redundant coercions, and SCCs where possible
-
-\begin{code}
-mkNote :: Note -> Expr b -> Expr b
-mkNote (Coerce to_ty1 from_ty1) (Note (Coerce to_ty2 from_ty2) expr)
- = ASSERT( from_ty1 == to_ty2 )
- mkNote (Coerce to_ty1 from_ty2) expr
-
-mkNote (SCC cc1) expr@(Note (SCC cc2) _)
- | isDupdCC cc1 -- Discard the outer SCC provided we don't need
- = expr -- to track its entry count
-
-mkNote note@(SCC cc1) expr@(Lam x e) -- Move _scc_ inside lambda
- = Lam x (mkNote note e)
-
--- Drop trivial InlineMe's
-mkNote InlineMe expr@(Con _ _) = expr
-mkNote InlineMe expr@(Var v) = expr
-
--- Slide InlineCall in around the function
--- No longer necessary I think (SLPJ Apr 99)
--- mkNote InlineCall (App f a) = App (mkNote InlineCall f) a
--- mkNote InlineCall (Var v) = Note InlineCall (Var v)
--- mkNote InlineCall expr = expr
-
-mkNote note expr = Note note expr
-\end{code}
%************************************************************************
%* *
rhssOfAlts :: [Alt b] -> [Expr b]
rhssOfAlts alts = [e | (_,_,e) <- alts]
-isDeadBinder :: CoreBndr -> Bool
-isDeadBinder bndr | isId bndr = case getIdOccInfo bndr of
- IAmDead -> True
- other -> False
- | otherwise = False -- TyVars count as not dead
-
flattenBinds :: [Bind b] -> [(b, Expr b)] -- Get all the lhs/rhs pairs
flattenBinds (NonRec b r : binds) = (b,r) : flattenBinds binds
flattenBinds (Rec prs1 : binds) = prs1 ++ flattenBinds binds
\end{code}
+
%************************************************************************
%* *
\subsection{Predicates}
\begin{code}
seqExpr :: CoreExpr -> ()
seqExpr (Var v) = v `seq` ()
-seqExpr (Con c as) = seqExprs as
+seqExpr (Lit lit) = lit `seq` ()
seqExpr (App f a) = seqExpr f `seq` seqExpr a
seqExpr (Lam b e) = seqBndr b `seq` seqExpr e
seqExpr (Let b e) = seqBind b `seq` seqExpr e
seq_rules (BuiltinRule _ : rules) = seq_rules rules
\end{code}
-\begin{code}
-coreBindsSize :: [CoreBind] -> Int
-coreBindsSize bs = foldr ((+) . bindSize) 0 bs
-
-exprSize :: CoreExpr -> Int
- -- A measure of the size of the expressions
- -- It also forces the expression pretty drastically as a side effect
-exprSize (Var v) = varSize v
-exprSize (Con c as) = c `seq` exprsSize as
-exprSize (App f a) = exprSize f + exprSize a
-exprSize (Lam b e) = varSize b + exprSize e
-exprSize (Let b e) = bindSize b + exprSize e
-exprSize (Case e b as) = exprSize e + varSize b + foldr ((+) . altSize) 0 as
-exprSize (Note n e) = exprSize e
-exprSize (Type t) = seqType t `seq` 1
-
-exprsSize = foldr ((+) . exprSize) 0
-
-varSize :: IdOrTyVar -> Int
-varSize b | isTyVar b = 1
- | otherwise = seqType (idType b) `seq`
- megaSeqIdInfo (idInfo b) `seq`
- 1
-
-varsSize = foldr ((+) . varSize) 0
-
-bindSize (NonRec b e) = varSize b + exprSize e
-bindSize (Rec prs) = foldr ((+) . pairSize) 0 prs
-
-pairSize (b,e) = varSize b + exprSize e
-
-altSize (c,bs,e) = c `seq` varsSize bs + exprSize e
-\end{code}
%************************************************************************
data AnnExpr' bndr annot
= AnnVar Id
- | AnnCon Con [AnnExpr bndr annot]
+ | AnnLit Literal
| AnnLam bndr (AnnExpr bndr annot)
| AnnApp (AnnExpr bndr annot) (AnnExpr bndr annot)
| AnnCase (AnnExpr bndr annot) bndr [AnnAlt bndr annot]
| AnnNote Note (AnnExpr bndr annot)
| AnnType Type
-type AnnAlt bndr annot = (Con, [bndr], AnnExpr bndr annot)
+type AnnAlt bndr annot = (AltCon, [bndr], AnnExpr bndr annot)
data AnnBind bndr annot
= AnnNonRec bndr (AnnExpr bndr annot)
\begin{code}
deAnnotate :: AnnExpr bndr annot -> Expr bndr
+deAnnotate (_, e) = deAnnotate' e
-deAnnotate (_, AnnType t) = Type t
-deAnnotate (_, AnnVar v) = Var v
-deAnnotate (_, AnnCon con args) = Con con (map deAnnotate args)
-deAnnotate (_, AnnLam binder body)= Lam binder (deAnnotate body)
-deAnnotate (_, AnnApp fun arg) = App (deAnnotate fun) (deAnnotate arg)
-deAnnotate (_, AnnNote note body) = Note note (deAnnotate body)
+deAnnotate' (AnnType t) = Type t
+deAnnotate' (AnnVar v) = Var v
+deAnnotate' (AnnLit lit) = Lit lit
+deAnnotate' (AnnLam binder body) = Lam binder (deAnnotate body)
+deAnnotate' (AnnApp fun arg) = App (deAnnotate fun) (deAnnotate arg)
+deAnnotate' (AnnNote note body) = Note note (deAnnotate body)
-deAnnotate (_, AnnLet bind body)
+deAnnotate' (AnnLet bind body)
= Let (deAnnBind bind) (deAnnotate body)
where
deAnnBind (AnnNonRec var rhs) = NonRec var (deAnnotate rhs)
deAnnBind (AnnRec pairs) = Rec [(v,deAnnotate rhs) | (v,rhs) <- pairs]
-deAnnotate (_, AnnCase scrut v alts)
+deAnnotate' (AnnCase scrut v alts)
= Case (deAnnotate scrut) v (map deAnnAlt alts)
- where
- deAnnAlt (con,args,rhs) = (con,args,deAnnotate rhs)
+
+deAnnAlt :: AnnAlt bndr annot -> Alt bndr
+deAnnAlt (con,args,rhs) = (con,args,deAnnotate rhs)
\end{code}
projects / ghc-hetmet.git / blobdiff