%
-% (c) The GRASP/AQUA Project, Glasgow University, 1992-1996
+% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
%
\section[CoreSyn]{A data type for the Haskell compiler midsection}
\begin{code}
-#include "HsVersions.h"
-
module CoreSyn (
- GenCoreBinding(..), GenCoreExpr(..),
- GenCoreArg(..), GenCoreBinder(..), GenCoreCaseAlts(..),
- GenCoreCaseDefault(..),
-
- bindersOf, pairsFromCoreBinds, rhssOfBind,
-
- mkGenApp, mkValApp, mkTyApp, mkUseApp,
- mkApp, mkCon, mkPrim,
- mkValLam, mkTyLam, mkUseLam,
- mkLam,
- collectBinders, isValBinder, notValBinder,
-
- collectArgs, isValArg, notValArg, numValArgs,
-
- mkCoLetAny, mkCoLetNoUnboxed, mkCoLetUnboxedToCase,
- mkCoLetsAny, mkCoLetsNoUnboxed, mkCoLetsUnboxedToCase,
- mkCoLetrecAny, mkCoLetrecNoUnboxed,
-
- rhssOfAlts,
-
- -- Common type instantiation...
- CoreBinding(..),
- CoreExpr(..),
- CoreBinder(..),
- CoreArg(..),
- CoreCaseAlts(..),
- CoreCaseDefault(..),
-
- -- And not-so-common type instantiations...
- TaggedCoreBinding(..),
- TaggedCoreExpr(..),
- TaggedCoreBinder(..),
- TaggedCoreArg(..),
- TaggedCoreCaseAlts(..),
- TaggedCoreCaseDefault(..),
-
- SimplifiableCoreBinding(..),
- SimplifiableCoreExpr(..),
- SimplifiableCoreBinder(..),
- SimplifiableCoreArg(..),
- SimplifiableCoreCaseAlts(..),
- SimplifiableCoreCaseDefault(..)
-
- -- and to make the interface self-sufficient ...
+ Expr(..), Alt, Bind(..), Arg(..), Note(..),
+ CoreExpr, CoreAlt, CoreBind, CoreArg, CoreBndr,
+ TaggedExpr, TaggedAlt, TaggedBind, TaggedArg,
- ) where
+ mkLets, mkLetBinds, mkLams,
+ mkApps, mkTyApps, mkValApps,
+ mkLit, mkStringLit, mkConApp, mkPrimApp, mkNote, mkNilExpr,
+ bindNonRec, mkIfThenElse, varToCoreExpr,
-import Ubiq{-uitous-}
+ bindersOf, rhssOfBind, rhssOfAlts, isDeadBinder, isTyVar, isId,
+ collectBinders, collectTyBinders, collectValBinders, collectTyAndValBinders,
+ collectArgs,
+ coreExprCc,
--- ToDo:rm:
---import PprCore ( GenCoreExpr{-instance-} )
---import PprStyle ( PprStyle(..) )
+ isValArg, isTypeArg, valArgCount,
-import CostCentre ( showCostCentre, CostCentre )
-import Id ( idType, GenId{-instance Eq-} )
-import Type ( isUnboxedType )
-import Usage ( UVar(..) )
-import Util ( panic, assertPanic {-pprTrace:ToDo:rm-} )
+ -- Annotated expressions
+ AnnExpr, AnnExpr'(..), AnnBind(..), AnnAlt, deAnnotate
+ ) where
+
+#include "HsVersions.h"
+
+import TysWiredIn ( boolTy, stringTy, nilDataCon )
+import CostCentre ( CostCentre, isDupdCC, noCostCentre )
+import Var ( Var, Id, TyVar, IdOrTyVar, isTyVar, isId, idType )
+import Id ( mkWildId, getInlinePragma )
+import Type ( Type, mkTyVarTy, isUnLiftedType )
+import IdInfo ( InlinePragInfo(..) )
+import Const ( Con(..), DataCon, Literal(NoRepStr), PrimOp )
+import TysWiredIn ( trueDataCon, falseDataCon )
+import Outputable
\end{code}
%************************************************************************
%* *
-\subsection[CoreTopBinding_and_CoreBinding]{@CoreTopBinding@ and @GenCoreBinding@}
+\subsection{The main data types}
%* *
%************************************************************************
-Core programs, bindings, expressions, etc., are parameterised with
-respect to the information kept about binding and bound occurrences of
-variables, called {\em binders} and {\em val_occ tyvar uvars}, respectively. [I
-don't really like the pair of names; I prefer {\em binder} and {\em
-bounder}. Or {\em binder} and {\em var}.]
+These data types are the heart of the compiler
-A @GenCoreBinding@ is either a single non-recursive binding of a
-``binder'' to an expression, or a mutually-recursive blob of same.
\begin{code}
-data GenCoreBinding val_bdr val_occ tyvar uvar
- = NonRec val_bdr (GenCoreExpr val_bdr val_occ tyvar uvar)
- | Rec [(val_bdr, GenCoreExpr val_bdr val_occ tyvar uvar)]
+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
+ | App (Expr b) (Arg b)
+ | Lam b (Expr b)
+ | Let (Bind b) (Expr b)
+ | Case (Expr b) b [Alt b] -- Binder gets bound to value of scrutinee
+ -- DEFAULT case must be last, if it occurs at all
+ | Note Note (Expr b)
+ | Type Type -- This should only show up at the top
+ -- level of an Arg
+
+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
+
+data Bind b = NonRec b (Expr b)
+ | Rec [(b, (Expr b))]
+
+data Note
+ = SCC CostCentre
+
+ | Coerce
+ Type -- The to-type: type of whole coerce expression
+ Type -- The from-type: type of enclosed expression
+
+ | InlineCall -- Instructs simplifier to inline
+ -- the enclosed call
\end{code}
-\begin{code}
-bindersOf :: GenCoreBinding val_bdr val_occ tyvar uvar -> [val_bdr]
-
-pairsFromCoreBinds ::
- [GenCoreBinding val_bdr val_occ tyvar uvar] ->
- [(val_bdr, GenCoreExpr val_bdr val_occ tyvar uvar)]
-
-rhssOfBind :: GenCoreBinding val_bdr val_occ tyvar uvar -> [GenCoreExpr val_bdr val_occ tyvar uvar]
-
-bindersOf (NonRec binder _) = [binder]
-bindersOf (Rec pairs) = [binder | (binder, _) <- pairs]
-
-pairsFromCoreBinds [] = []
-pairsFromCoreBinds ((NonRec b e) : bs) = (b,e) : pairsFromCoreBinds bs
-pairsFromCoreBinds ((Rec pairs) : bs) = pairs ++ pairsFromCoreBinds bs
-
-rhssOfBind (NonRec _ rhs) = [rhs]
-rhssOfBind (Rec pairs) = [rhs | (_,rhs) <- pairs]
-\end{code}
%************************************************************************
%* *
-\subsection[GenCoreExpr]{Core expressions: @GenCoreExpr@}
+\subsection{Useful synonyms}
%* *
%************************************************************************
-@GenCoreExpr@ is the heart of the ``core'' data types; it is
-(more-or-less) boiled-down second-order polymorphic lambda calculus.
-For types in the core world, we just keep using @Types@.
-\begin{code}
-data GenCoreExpr val_bdr val_occ tyvar uvar
- = Var val_occ
- | Lit Literal -- literal constants
-\end{code}
-
-@Cons@ and @Prims@ are saturated constructor and primitive-op
-applications (see the comment). Note: @Con@s are only set up by the
-simplifier (and by the desugarer when it knows what it's doing). The
-desugarer sets up constructors as applications of global @Vars@s.
+The common case
\begin{code}
- | Con Id [GenCoreArg val_occ tyvar uvar]
- -- Saturated constructor application:
- -- The constructor is a function of the form:
- -- /\ a1 -> ... /\ am -> \ b1 -> ... \ bn ->
- -- <expr> where "/\" is a type lambda and "\" the
- -- regular kind; there will be "m" Types and
- -- "n" bindees in the Con args.
-
- | Prim PrimOp [GenCoreArg val_occ tyvar uvar]
- -- saturated primitive operation;
- -- comment on Cons applies here, too.
+type CoreBndr = IdOrTyVar
+type CoreExpr = Expr CoreBndr
+type CoreArg = Arg CoreBndr
+type CoreBind = Bind CoreBndr
+type CoreAlt = Alt CoreBndr
+type CoreNote = Note
\end{code}
-Ye olde abstraction and application operators.
-\begin{code}
- | Lam (GenCoreBinder val_bdr tyvar uvar)
- (GenCoreExpr val_bdr val_occ tyvar uvar)
-
- | App (GenCoreExpr val_bdr val_occ tyvar uvar)
- (GenCoreArg val_occ tyvar uvar)
-\end{code}
-
-Case expressions (\tr{case <expr> of <List of alternatives>}): there
-are really two flavours masquerading here---those for scrutinising
-{\em algebraic} types and those for {\em primitive} types. Please see
-under @GenCoreCaseAlts@.
-\begin{code}
- | Case (GenCoreExpr val_bdr val_occ tyvar uvar)
- (GenCoreCaseAlts val_bdr val_occ tyvar uvar)
-\end{code}
-
-A Core case expression \tr{case e of v -> ...} implies evaluation of
-\tr{e}; it is not equivalent to \tr{let v = in ...} (as with a Haskell
-\tr{case}).
+Binders are ``tagged'' with a \tr{t}:
-Non-recursive @Lets@ only have one binding; having more than one
-doesn't buy you much, and it is an easy way to mess up variable
-scoping.
\begin{code}
- | Let (GenCoreBinding val_bdr val_occ tyvar uvar)
- (GenCoreExpr val_bdr val_occ tyvar uvar)
- -- both recursive and non-.
- -- The "GenCoreBinding" records that information
-\end{code}
+type Tagged t = (CoreBndr, t)
-For cost centre scc expressions we introduce a new core construct
-@SCC@ so transforming passes have to deal with it explicitly. The
-alternative of using a new PrimativeOp may result in a bad
-transformations of which we are unaware.
-\begin{code}
- | SCC CostCentre -- label of scc
- (GenCoreExpr val_bdr val_occ tyvar uvar) -- scc expression
+type TaggedBind t = Bind (Tagged t)
+type TaggedExpr t = Expr (Tagged t)
+type TaggedArg t = Arg (Tagged t)
+type TaggedAlt t = Alt (Tagged t)
\end{code}
%* *
%************************************************************************
-When making @Lets@, we may want to take evasive action if the thing
-being bound has unboxed type. We have different variants ...
-
-@mkCoLet(s|rec)Any@ let-binds any binding, regardless of type
-@mkCoLet(s|rec)NoUnboxed@ prohibits unboxed bindings
-@mkCoLet(s)UnboxedToCase@ converts an unboxed binding to a case
- (unboxed bindings in a letrec are still prohibited)
-
\begin{code}
-mkCoLetAny :: GenCoreBinding Id Id tyvar uvar
- -> GenCoreExpr Id Id tyvar uvar
- -> GenCoreExpr Id Id tyvar uvar
-mkCoLetsAny :: [GenCoreBinding Id Id tyvar uvar] ->
- GenCoreExpr Id Id tyvar uvar ->
- GenCoreExpr Id Id tyvar uvar
-
-mkCoLetrecAny :: [(val_bdr, GenCoreExpr val_bdr val_occ tyvar uvar)]
- -> GenCoreExpr val_bdr val_occ tyvar uvar
- -> GenCoreExpr val_bdr val_occ tyvar uvar
-
-mkCoLetrecAny [] body = body
-mkCoLetrecAny binds body = Let (Rec binds) body
-
-mkCoLetsAny [] expr = expr
-mkCoLetsAny binds expr = foldr mkCoLetAny expr binds
-
-mkCoLetAny bind@(Rec binds) body = mkCoLetrecAny binds body
-mkCoLetAny bind@(NonRec binder rhs) body
- = case body of
- Var binder2 | binder == binder2
- -> rhs -- hey, I have the rhs
- other
- -> Let bind body
+mkApps :: Expr b -> [Arg b] -> Expr b
+mkTyApps :: Expr b -> [Type] -> Expr b
+mkValApps :: Expr b -> [Expr b] -> Expr b
+
+mkApps f args = foldl App f args
+mkTyApps f args = foldl (\ e a -> App e (Type a)) f args
+mkValApps f args = foldl (\ e a -> App e a) f args
+
+mkLit :: Literal -> Expr b
+mkStringLit :: String -> Expr b
+mkConApp :: DataCon -> [Arg b] -> Expr b
+mkPrimApp :: PrimOp -> [Arg b] -> Expr b
+
+mkLit lit = Con (Literal lit) []
+mkStringLit str = Con (Literal (NoRepStr (_PK_ str) stringTy)) []
+mkConApp con args = Con (DataCon con) args
+mkPrimApp op args = Con (PrimOp op) args
+
+mkNilExpr :: Type -> CoreExpr
+mkNilExpr ty = Con (DataCon nilDataCon) [Type ty]
+
+varToCoreExpr :: CoreBndr -> CoreExpr
+varToCoreExpr v | isId v = Var v
+ | otherwise = Type (mkTyVarTy v)
\end{code}
\begin{code}
---mkCoLetNoUnboxed ::
--- GenCoreBinding val_bdr val_occ tyvar uvar ->
--- GenCoreExpr val_bdr val_occ tyvar uvar ->
--- GenCoreExpr val_bdr val_occ tyvar uvar
-
-mkCoLetNoUnboxed bind@(Rec binds) body
- = mkCoLetrecNoUnboxed binds body
-mkCoLetNoUnboxed bind@(NonRec binder rhs) body
- = --ASSERT (not (isUnboxedType (idType binder)))
- case body of
- Var binder2 | binder == binder2
- -> rhs -- hey, I have the rhs
- other
- -> Let bind body
-
-mkCoLetsNoUnboxed [] expr = expr
-mkCoLetsNoUnboxed binds expr = foldr mkCoLetNoUnboxed expr binds
-
---mkCoLetrecNoUnboxed :: [(Id, CoreExpr)] -- bindings
--- -> CoreExpr -- body
--- -> CoreExpr -- result
-
-mkCoLetrecNoUnboxed [] body = body
-mkCoLetrecNoUnboxed binds body
- = ASSERT (all is_boxed_bind binds)
- Let (Rec binds) body
- where
- is_boxed_bind (binder, rhs)
- = (not . isUnboxedType . idType) binder
+mkLams :: [b] -> Expr b -> Expr b
+mkLams binders body = foldr Lam body binders
\end{code}
\begin{code}
---mkCoLetUnboxedToCase ::
--- GenCoreBinding val_bdr val_occ tyvar uvar ->
--- GenCoreExpr val_bdr val_occ tyvar uvar ->
--- GenCoreExpr val_bdr val_occ tyvar uvar
-
-mkCoLetUnboxedToCase bind@(Rec binds) body
- = mkCoLetrecNoUnboxed binds body
-mkCoLetUnboxedToCase bind@(NonRec binder rhs) body
- = case body of
- Var binder2 | binder == binder2
- -> rhs -- hey, I have the rhs
- other
- -> if (not (isUnboxedType (idType binder))) then
- Let bind body -- boxed...
- else
- Case rhs -- unboxed...
- (PrimAlts []
- (BindDefault binder body))
-
-mkCoLetsUnboxedToCase [] expr = expr
-mkCoLetsUnboxedToCase binds expr = foldr mkCoLetUnboxedToCase expr binds
+mkLets :: [Bind b] -> Expr b -> Expr b
+mkLets binds body = foldr Let body binds
+
+mkLetBinds :: [CoreBind] -> CoreExpr -> CoreExpr
+-- mkLetBinds is like mkLets, but it uses bindNonRec to
+-- make a case binding for unlifted things
+mkLetBinds [] body = body
+mkLetBinds (NonRec b r : binds) body = bindNonRec b r (mkLetBinds binds body)
+mkLetBinds (bind : binds) body = Let bind (mkLetBinds binds body)
+
+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
+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}
-%************************************************************************
-%* *
-\subsection{Case alternatives in @GenCoreExpr@}
-%* *
-%************************************************************************
-
-We have different kinds of @case@s, the differences being reflected in
-the kinds of alternatives a case has. We maintain a distinction
-between cases for scrutinising algebraic datatypes, as opposed to
-primitive types. In both cases, we carry around a @TyCon@, as a
-handle with which we can get info about the case (e.g., total number
-of data constructors for this type).
-
-For example:
-\begin{verbatim}
-let# x=e in b
-\end{verbatim}
-becomes
-\begin{verbatim}
-Case e [ BindDefaultAlt x -> b ]
-\end{verbatim}
+mkNote removes redundant coercions, and SCCs where possible
\begin{code}
-data GenCoreCaseAlts val_bdr val_occ tyvar uvar
- = AlgAlts [(Id, -- alts: data constructor,
- [val_bdr], -- constructor's parameters,
- GenCoreExpr val_bdr val_occ tyvar uvar)] -- rhs.
- (GenCoreCaseDefault val_bdr val_occ tyvar uvar)
-
- | PrimAlts [(Literal, -- alts: unboxed literal,
- GenCoreExpr val_bdr val_occ tyvar uvar)] -- rhs.
- (GenCoreCaseDefault val_bdr val_occ tyvar uvar)
-
--- obvious things: if there are no alts in the list, then the default
--- can't be NoDefault.
-
-data GenCoreCaseDefault val_bdr val_occ tyvar uvar
- = NoDefault -- small con family: all
- -- constructor accounted for
- | BindDefault val_bdr -- form: var -> expr;
- (GenCoreExpr val_bdr val_occ tyvar uvar) -- "val_bdr" may or may not
- -- be used in RHS.
-\end{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
-\begin{code}
-rhssOfAlts (AlgAlts alts deflt) = rhssOfDeflt deflt ++ [rhs | (_,_,rhs) <- alts]
-rhssOfAlts (PrimAlts alts deflt) = rhssOfDeflt deflt ++ [rhs | (_,rhs) <- alts]
+mkNote (SCC cc1) expr@(Note (SCC cc2) _)
+ | isDupdCC cc1 -- Discard the outer SCC provided we don't need
+ = expr -- to track its entry count
-rhssOfDeflt NoDefault = []
-rhssOfDeflt (BindDefault _ rhs) = [rhs]
+mkNote note@(SCC cc1) expr@(Lam x e) -- Move _scc_ inside lambda
+ = Lam x (mkNote note e)
+
+-- Slide InlineCall in around the function
+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}
%************************************************************************
%* *
-\subsection{Core binders}
+\subsection{Simple access functions}
%* *
%************************************************************************
\begin{code}
-data GenCoreBinder val_bdr tyvar uvar
- = ValBinder val_bdr
- | TyBinder tyvar
- | UsageBinder uvar
-
-isValBinder (ValBinder _) = True
-isValBinder _ = False
+bindersOf :: Bind b -> [b]
+bindersOf (NonRec binder _) = [binder]
+bindersOf (Rec pairs) = [binder | (binder, _) <- pairs]
-notValBinder = not . isValBinder
-\end{code}
+rhssOfBind :: Bind b -> [Expr b]
+rhssOfBind (NonRec _ rhs) = [rhs]
+rhssOfBind (Rec pairs) = [rhs | (_,rhs) <- pairs]
-Clump Lams together if possible.
+rhssOfAlts :: [Alt b] -> [Expr b]
+rhssOfAlts alts = [e | (_,_,e) <- alts]
-\begin{code}
-mkValLam :: [val_bdr]
- -> GenCoreExpr val_bdr val_occ tyvar uvar
- -> GenCoreExpr val_bdr val_occ tyvar uvar
-mkTyLam :: [tyvar]
- -> GenCoreExpr val_bdr val_occ tyvar uvar
- -> GenCoreExpr val_bdr val_occ tyvar uvar
-mkUseLam :: [uvar]
- -> GenCoreExpr val_bdr val_occ tyvar uvar
- -> GenCoreExpr val_bdr val_occ tyvar uvar
-
-mkValLam binders body = foldr (Lam . ValBinder) body binders
-mkTyLam binders body = foldr (Lam . TyBinder) body binders
-mkUseLam binders body = foldr (Lam . UsageBinder) body binders
-
-mkLam :: [tyvar] -> [val_bdr] -- ToDo: could add a [uvar] arg...
- -> GenCoreExpr val_bdr val_occ tyvar uvar
- -> GenCoreExpr val_bdr val_occ tyvar uvar
-
-mkLam tyvars valvars body
- = mkTyLam tyvars (mkValLam valvars body)
+isDeadBinder :: CoreBndr -> Bool
+isDeadBinder bndr | isId bndr = case getInlinePragma bndr of
+ IAmDead -> True
+ other -> False
+ | otherwise = False -- TyVars count as not dead
\end{code}
We often want to strip off leading lambdas before getting down to
business. @collectBinders@ is your friend.
-We expect (by convention) usage-, type-, and value- lambdas in that
+We expect (by convention) type-, and value- lambdas in that
order.
\begin{code}
-collectBinders ::
- GenCoreExpr val_bdr val_occ tyvar uvar ->
- ([uvar], [tyvar], [val_bdr], GenCoreExpr val_bdr val_occ tyvar uvar)
+collectBinders :: Expr b -> ([b], Expr b)
+collectTyBinders :: CoreExpr -> ([TyVar], CoreExpr)
+collectValBinders :: CoreExpr -> ([Id], CoreExpr)
+collectTyAndValBinders :: CoreExpr -> ([TyVar], [Id], CoreExpr)
-collectBinders expr
- = usages expr []
+collectTyAndValBinders expr
+ = (tvs, ids, body)
where
- usages (Lam (UsageBinder u) body) uacc = usages body (u:uacc)
- usages other uacc
- = case (tyvars other []) of { (tacc, vacc, expr) ->
- (reverse uacc, tacc, vacc, expr) }
-
- tyvars (Lam (TyBinder t) body) tacc = tyvars body (t:tacc)
- tyvars other tacc
- = ASSERT(not (usage_lambda other))
- case (valvars other []) of { (vacc, expr) ->
- (reverse tacc, vacc, expr) }
-
- valvars (Lam (ValBinder v) body) vacc = valvars body (v:vacc)
- valvars other vacc
- = ASSERT(not (usage_lambda other))
- ASSERT(not (tyvar_lambda other))
- (reverse vacc, other)
-
- ---------------------------------------
- usage_lambda (Lam (UsageBinder _) _) = True
- usage_lambda _ = False
-
- tyvar_lambda (Lam (TyBinder _) _) = True
- tyvar_lambda _ = False
-\end{code}
+ (tvs, body1) = collectTyBinders expr
+ (ids, body) = collectValBinders body1
-%************************************************************************
-%* *
-\subsection{Core arguments (atoms)}
-%* *
-%************************************************************************
+collectBinders expr
+ = go [] expr
+ where
+ go tvs (Lam b e) = go (b:tvs) e
+ go tvs e = (reverse tvs, e)
-\begin{code}
-data GenCoreArg val_occ tyvar uvar
- = LitArg Literal
- | VarArg val_occ
- | TyArg (GenType tyvar uvar)
- | UsageArg (GenUsage uvar)
-\end{code}
+collectTyBinders expr
+ = go [] expr
+ where
+ go tvs (Lam b e) | isTyVar b = go (b:tvs) e
+ go tvs e = (reverse tvs, e)
-General and specific forms:
-\begin{code}
-mkGenApp :: GenCoreExpr val_bdr val_occ tyvar uvar
- -> [GenCoreArg val_occ tyvar uvar]
- -> GenCoreExpr val_bdr val_occ tyvar uvar
-mkTyApp :: GenCoreExpr val_bdr val_occ tyvar uvar
- -> [GenType tyvar uvar]
- -> GenCoreExpr val_bdr val_occ tyvar uvar
-mkUseApp :: GenCoreExpr val_bdr val_occ tyvar uvar
- -> [GenUsage uvar]
- -> GenCoreExpr val_bdr val_occ tyvar uvar
-mkValApp :: GenCoreExpr val_bdr val_occ tyvar uvar
- -> [GenCoreArg val_occ tyvar uvar] -- but we ASSERT they are LitArg or VarArg
- -> GenCoreExpr val_bdr val_occ tyvar uvar
-
-mkGenApp f args = foldl App f args
-mkTyApp f args = foldl (\ e a -> App e (TyArg a)) f args
-mkUseApp f args = foldl (\ e a -> App e (UsageArg a)) f args
-mkValApp f args = foldl (\ e a -> App e (is_Lit_or_Var a)) f args
-
-#ifndef DEBUG
-is_Lit_or_Var a = a
-#else
-is_Lit_or_Var a
- = if isValArg a then a else panic "CoreSyn.mkValApps:not LitArg or VarArg"
-#endif
-
-isValArg (LitArg _) = True -- often used for sanity-checking
-isValArg (VarArg _) = True
-isValArg _ = False
-
-notValArg = not . isValArg -- exists only because it's a common use of isValArg
-
-numValArgs as = length [ a | a <- as, isValArg a ] -- again, convenience
+collectValBinders expr
+ = go [] expr
+ where
+ go ids (Lam b e) | isId b = go (b:ids) e
+ go ids body = (reverse ids, body)
\end{code}
-\begin{code}
-mkApp fun = mk_thing (mkGenApp fun)
-mkCon con = mk_thing (Con con)
-mkPrim op = mk_thing (Prim op)
-
-mk_thing thing uses tys vals
- = thing (map UsageArg uses ++ map TyArg tys ++ map is_Lit_or_Var vals)
-\end{code}
@collectArgs@ takes an application expression, returning the function
and the arguments to which it is applied.
\begin{code}
-collectArgs :: GenCoreExpr val_bdr val_occ tyvar uvar
- -> (GenCoreExpr val_bdr val_occ tyvar uvar,
- [GenUsage uvar],
- [GenType tyvar uvar],
- [GenCoreArg val_occ tyvar uvar]{-ValArgs-})
-
+collectArgs :: Expr b -> (Expr b, [Arg b])
collectArgs expr
- = usages expr []
+ = go expr []
where
- usages (App fun (UsageArg u)) uacc = usages fun (u:uacc)
- usages fun uacc
- = case (tyvars fun []) of { (expr, tacc, vacc) ->
- (expr, uacc, tacc, vacc) }
-
- tyvars (App fun (TyArg t)) tacc = tyvars fun (t:tacc)
- tyvars fun tacc
- = ASSERT(not (usage_app fun))
- case (valvars fun []) of { (expr, vacc) ->
- (expr, tacc, vacc) }
-
- valvars (App fun v) vacc | isValArg v = valvars fun (v:vacc)
- valvars fun vacc
- = --ASSERT(not (usage_app fun))
- --ASSERT(not (ty_app fun))
- (if (usage_app fun || ty_app fun) then trace "CoreSyn:valvars" {-(ppr PprDebug fun)-} else id) $
- (fun, vacc)
-
- ---------------------------------------
- usage_app (App _ (UsageArg _)) = True
- usage_app _ = False
-
- ty_app (App _ (TyArg _)) = True
- ty_app _ = False
+ go (App f a) as = go f (a:as)
+ go e as = (e, as)
\end{code}
-%************************************************************************
-%* *
-\subsection{The main @Core*@ instantiation of the @GenCore*@ types}
-%* *
-%************************************************************************
+coreExprCc gets the cost centre enclosing an expression, if any.
+It looks inside lambdas because (scc "foo" \x.e) = \x.scc "foo" e
\begin{code}
-type CoreBinding = GenCoreBinding Id Id TyVar UVar
-type CoreExpr = GenCoreExpr Id Id TyVar UVar
-type CoreBinder = GenCoreBinder Id TyVar UVar
-type CoreArg = GenCoreArg Id TyVar UVar
-
-type CoreCaseAlts = GenCoreCaseAlts Id Id TyVar UVar
-type CoreCaseDefault = GenCoreCaseDefault Id Id TyVar UVar
+coreExprCc :: Expr b -> CostCentre
+coreExprCc (Note (SCC cc) e) = cc
+coreExprCc (Note other_note e) = coreExprCc e
+coreExprCc (Lam _ e) = coreExprCc e
+coreExprCc other = noCostCentre
\end{code}
+
%************************************************************************
%* *
-\subsection{The @TaggedCore*@ instantiation of the @GenCore*@ types}
+\subsection{Predicates}
%* *
%************************************************************************
-Binders are ``tagged'' with a \tr{t}:
\begin{code}
-type Tagged t = (Id, t)
+isValArg (Type _) = False
+isValArg other = True
-type TaggedCoreBinding t = GenCoreBinding (Tagged t) Id TyVar UVar
-type TaggedCoreExpr t = GenCoreExpr (Tagged t) Id TyVar UVar
-type TaggedCoreBinder t = GenCoreBinder (Tagged t) TyVar UVar
-type TaggedCoreArg t = GenCoreArg Id TyVar UVar
+isTypeArg (Type _) = True
+isTypeArg other = False
-type TaggedCoreCaseAlts t = GenCoreCaseAlts (Tagged t) Id TyVar UVar
-type TaggedCoreCaseDefault t = GenCoreCaseDefault (Tagged t) Id TyVar UVar
+valArgCount :: [Arg b] -> Int
+valArgCount [] = 0
+valArgCount (Type _ : args) = valArgCount args
+valArgCount (other : args) = 1 + valArgCount args
\end{code}
+
%************************************************************************
%* *
-\subsection{The @SimplifiableCore*@ instantiation of the @GenCore*@ types}
+\subsection{Annotated core; annotation at every node in the tree}
%* *
%************************************************************************
-Binders are tagged with @BinderInfo@:
\begin{code}
-type Simplifiable = (Id, BinderInfo)
+type AnnExpr bndr annot = (annot, AnnExpr' bndr annot)
+
+data AnnExpr' bndr annot
+ = AnnVar Id
+ | AnnCon Con [AnnExpr bndr annot]
+ | AnnLam bndr (AnnExpr bndr annot)
+ | AnnApp (AnnExpr bndr annot) (AnnExpr bndr annot)
+ | AnnCase (AnnExpr bndr annot) bndr [AnnAlt bndr annot]
+ | AnnLet (AnnBind bndr annot) (AnnExpr bndr annot)
+ | AnnNote Note (AnnExpr bndr annot)
+ | AnnType Type
+
+type AnnAlt bndr annot = (Con, [bndr], AnnExpr bndr annot)
+
+data AnnBind bndr annot
+ = AnnNonRec bndr (AnnExpr bndr annot)
+ | AnnRec [(bndr, AnnExpr bndr annot)]
+\end{code}
+
+\begin{code}
+deAnnotate :: AnnExpr bndr annot -> Expr bndr
+
+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)
-type SimplifiableCoreBinding = GenCoreBinding Simplifiable Id TyVar UVar
-type SimplifiableCoreExpr = GenCoreExpr Simplifiable Id TyVar UVar
-type SimplifiableCoreBinder = GenCoreBinder Simplifiable TyVar UVar
-type SimplifiableCoreArg = GenCoreArg Id TyVar UVar
+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]
-type SimplifiableCoreCaseAlts = GenCoreCaseAlts Simplifiable Id TyVar UVar
-type SimplifiableCoreCaseDefault = GenCoreCaseDefault Simplifiable Id TyVar UVar
+deAnnotate (_, AnnCase scrut v alts)
+ = Case (deAnnotate scrut) v (map deAnnAlt alts)
+ where
+ deAnnAlt (con,args,rhs) = (con,args,deAnnotate rhs)
\end{code}
+