%
-% (c) The GRASP/AQUA Project, Glasgow University, 1993-1996
+% (c) The GRASP/AQUA Project, Glasgow University, 1993-1998
%
%************************************************************************
%* *
%************************************************************************
We could either use this, or parameterise @GenCoreExpr@ on @Types@ and
-@TyVars@ as well. Currently trying the former.
+@TyVars@ as well. Currently trying the former... MEGA SIGH.
\begin{code}
-#include "HsVersions.h"
-
module HsCore (
- UnfoldingCoreExpr(..), UnfoldingCoreAlts(..),
- UnfoldingCoreDefault(..), UnfoldingCoreBinding(..),
- UnfoldingCoreAtom(..), UfId(..), UnfoldingType(..),
- UnfoldingPrimOp(..), UfCostCentre(..)
+ UfExpr(..), UfAlt, UfBinder(..), UfNote(..),
+ UfBinding(..), UfConAlt(..),
+ HsIdInfo(..), pprHsIdInfo,
+
+ eq_ufExpr, eq_ufBinders, pprUfExpr, pprHsIdInfo,
+
+ toUfExpr, toUfBndr, ufBinderName
) where
-IMP_Ubiq()
+#include "HsVersions.h"
-- friends:
-import HsTypes ( MonoType, PolyType )
-import PrimOp ( PrimOp, tagOf_PrimOp )
+import HsTypes ( HsType, pprParendHsType, pprHsTyVarBndr, toHsType,
+ HsTupCon(..), EqHsEnv, hsTupParens,
+ emptyEqHsEnv, extendEqHsEnv, eqListBy,
+ eq_hsType, eq_hsVars
+ )
-- others:
-import Literal ( Literal )
-import Outputable ( Outputable(..) )
-import Pretty
-import Util ( panic )
+import Id ( idArity, idType, isDataConId_maybe, isFCallId_maybe )
+import Var ( varType, isId )
+import IdInfo ( InlinePragInfo, pprInlinePragInfo, ppStrictnessInfo )
+import Name ( Name, NamedThing(..), getName, toRdrName )
+import RdrName ( RdrName, rdrNameOcc )
+import OccName ( isTvOcc )
+import CoreSyn
+import CostCentre ( pprCostCentreCore )
+import Demand ( StrictnessInfo )
+import Literal ( Literal, maybeLitLit )
+import ForeignCall ( ForeignCall )
+import DataCon ( dataConTyCon, dataConSourceArity )
+import TyCon ( isTupleTyCon, tupleTyConBoxity )
+import Type ( Kind )
+import BasicTypes ( Arity )
+import FiniteMap ( lookupFM )
+import CostCentre
+import Outputable
\end{code}
%************************************************************************
%************************************************************************
\begin{code}
-data UnfoldingCoreExpr name
- = UfVar (UfId name)
+data UfExpr name
+ = UfVar name
+ | UfType (HsType name)
+ | UfTuple (HsTupCon name) [UfExpr name] -- Type arguments omitted
+ | UfLam (UfBinder name) (UfExpr name)
+ | UfApp (UfExpr name) (UfExpr name)
+ | UfCase (UfExpr name) name [UfAlt name]
+ | UfLet (UfBinding name) (UfExpr name)
+ | UfNote (UfNote name) (UfExpr name)
| UfLit Literal
- | UfCon name -- must be a "BoringUfId"...
- [UnfoldingType name]
- [UnfoldingCoreAtom name]
- | UfPrim (UnfoldingPrimOp name)
- [UnfoldingType name]
- [UnfoldingCoreAtom name]
- | UfLam (UfBinder name)
- (UnfoldingCoreExpr name)
- | UfApp (UnfoldingCoreExpr name)
- (UnfoldingCoreAtom name)
- | UfCase (UnfoldingCoreExpr name)
- (UnfoldingCoreAlts name)
- | UfLet (UnfoldingCoreBinding name)
- (UnfoldingCoreExpr name)
- | UfSCC (UfCostCentre name)
- (UnfoldingCoreExpr name)
-
-data UnfoldingPrimOp name
- = UfCCallOp FAST_STRING -- callee
- Bool -- True <=> casm, rather than ccall
- Bool -- True <=> might cause GC
- [UnfoldingType name] -- arg types, incl state token
- -- (which will be first)
- (UnfoldingType name) -- return type
- | UfOtherOp PrimOp
-
-data UnfoldingCoreAlts name
- = UfCoAlgAlts [(name, [UfBinder name], UnfoldingCoreExpr name)]
- (UnfoldingCoreDefault name)
- | UfCoPrimAlts [(Literal, UnfoldingCoreExpr name)]
- (UnfoldingCoreDefault name)
-
-data UnfoldingCoreDefault name
- = UfCoNoDefault
- | UfCoBindDefault (UfBinder name)
- (UnfoldingCoreExpr name)
-
-data UnfoldingCoreBinding name
- = UfCoNonRec (UfBinder name)
- (UnfoldingCoreExpr name)
- | UfCoRec [(UfBinder name, UnfoldingCoreExpr name)]
-
-data UnfoldingCoreAtom name
- = UfCoVarAtom (UfId name)
- | UfCoLitAtom Literal
-
-data UfCostCentre name
- = UfPreludeDictsCC
- Bool -- True <=> is dupd
- | UfAllDictsCC FAST_STRING -- module and group
- FAST_STRING
- Bool -- True <=> is dupd
- | UfUserCC FAST_STRING
- FAST_STRING FAST_STRING -- module and group
- Bool -- True <=> is dupd
- Bool -- True <=> is CAF
- | UfAutoCC (UfId name)
- FAST_STRING FAST_STRING -- module and group
- Bool Bool -- as above
- | UfDictCC (UfId name)
- FAST_STRING FAST_STRING -- module and group
- Bool Bool -- as above
-
-type UfBinder name = (name, UnfoldingType name)
-
-data UfId name
- = BoringUfId name
- | SuperDictSelUfId name name -- class and superclass
- | ClassOpUfId name name -- class and class op
- | DictFunUfId name -- class and type
- (UnfoldingType name)
- | ConstMethodUfId name name -- class, class op, and type
- (UnfoldingType name)
- | DefaultMethodUfId name name -- class and class op
- | SpecUfId (UfId name) -- its unspecialised "parent"
- [Maybe (MonoType name)]
- | WorkerUfId (UfId name) -- its non-working "parent"
- -- more to come?
-
-type UnfoldingType name = PolyType name
+ | UfLitLit FAST_STRING (HsType name)
+ | UfFCall ForeignCall (HsType name)
+
+data UfNote name = UfSCC CostCentre
+ | UfCoerce (HsType name)
+ | UfInlineCall
+ | UfInlineMe
+
+type UfAlt name = (UfConAlt name, [name], UfExpr name)
+
+data UfConAlt name = UfDefault
+ | UfDataAlt name
+ | UfTupleAlt (HsTupCon name)
+ | UfLitAlt Literal
+ | UfLitLitAlt FAST_STRING (HsType name)
+
+data UfBinding name
+ = UfNonRec (UfBinder name)
+ (UfExpr name)
+ | UfRec [(UfBinder name, UfExpr name)]
+
+data UfBinder name
+ = UfValBinder name (HsType name)
+ | UfTyBinder name Kind
+
+ufBinderName :: UfBinder name -> name
+ufBinderName (UfValBinder n _) = n
+ufBinderName (UfTyBinder n _) = n
\end{code}
+
%************************************************************************
%* *
-\subsection[HsCore-print]{Printing Core unfoldings}
+\subsection{Converting from Core to UfCore}
%* *
%************************************************************************
\begin{code}
-instance Outputable name => Outputable (UnfoldingCoreExpr name) where
- ppr sty (UfVar v) = pprUfId sty v
- ppr sty (UfLit l) = ppr sty l
+toUfExpr :: CoreExpr -> UfExpr Name
+toUfExpr (Var v) = toUfVar v
+toUfExpr (Lit l) = case maybeLitLit l of
+ Just (s,ty) -> UfLitLit s (toHsType ty)
+ Nothing -> UfLit l
+toUfExpr (Type ty) = UfType (toHsType ty)
+toUfExpr (Lam x b) = UfLam (toUfBndr x) (toUfExpr b)
+toUfExpr (App f a) = toUfApp f [a]
+toUfExpr (Case s x as) = UfCase (toUfExpr s) (getName x) (map toUfAlt as)
+toUfExpr (Let b e) = UfLet (toUfBind b) (toUfExpr e)
+toUfExpr (Note n e) = UfNote (toUfNote n) (toUfExpr e)
+
+---------------------
+toUfNote (SCC cc) = UfSCC cc
+toUfNote (Coerce t1 _) = UfCoerce (toHsType t1)
+toUfNote InlineCall = UfInlineCall
+toUfNote InlineMe = UfInlineMe
+
+---------------------
+toUfBind (NonRec b r) = UfNonRec (toUfBndr b) (toUfExpr r)
+toUfBind (Rec prs) = UfRec [(toUfBndr b, toUfExpr r) | (b,r) <- prs]
+
+---------------------
+toUfAlt (c,bs,r) = (toUfCon c, map getName bs, toUfExpr r)
+
+---------------------
+toUfCon (DataAlt dc) | isTupleTyCon tc = UfTupleAlt (mk_hs_tup_con tc dc)
+ | otherwise = UfDataAlt (getName dc)
+ where
+ tc = dataConTyCon dc
+
+toUfCon (LitAlt l) = case maybeLitLit l of
+ Just (s,ty) -> UfLitLitAlt s (toHsType ty)
+ Nothing -> UfLitAlt l
+toUfCon DEFAULT = UfDefault
+
+---------------------
+mk_hs_tup_con tc dc = HsTupCon (getName dc) (tupleTyConBoxity tc) (dataConSourceArity dc)
+
+---------------------
+toUfBndr x | isId x = UfValBinder (getName x) (toHsType (varType x))
+ | otherwise = UfTyBinder (getName x) (varType x)
+
+---------------------
+toUfApp (App f a) as = toUfApp f (a:as)
+toUfApp (Var v) as
+ = case isDataConId_maybe v of
+ -- We convert the *worker* for tuples into UfTuples
+ Just dc | isTupleTyCon tc && saturated
+ -> UfTuple (mk_hs_tup_con tc dc) tup_args
+ where
+ val_args = dropWhile isTypeArg as
+ saturated = length val_args == idArity v
+ tup_args = map toUfExpr val_args
+ tc = dataConTyCon dc
+ ;
+
+ other -> mkUfApps (toUfVar v) as
- ppr sty (UfCon c tys as)
- = ppCat [ppStr "(UfCon", ppr sty c, ppr sty tys, ppr sty as, ppStr ")"]
- ppr sty (UfPrim o tys as)
- = ppCat [ppStr "(UfPrim", ppr sty o, ppr sty tys, ppr sty as, ppStr ")"]
+toUfApp e as = mkUfApps (toUfExpr e) as
- ppr sty (UfLam bs body)
- = ppCat [ppChar '\\', ppr sty bs, ppStr "->", ppr sty body]
+mkUfApps = foldl (\f a -> UfApp f (toUfExpr a))
+
+---------------------
+toUfVar v = case isFCallId_maybe v of
+ -- Foreign calls have special syntax
+ Just fcall -> UfFCall fcall (toHsType (idType v))
+ other -> UfVar (getName v)
+\end{code}
- ppr sty (UfApp fun arg)
- = ppCat [ppStr "(UfApp", ppr sty fun, ppr sty arg, ppStr ")"]
- ppr sty (UfCase scrut alts)
- = ppCat [ppStr "case", ppr sty scrut, ppStr "of {", pp_alts alts, ppStr "}"]
+%************************************************************************
+%* *
+\subsection[HsCore-print]{Printing Core unfoldings}
+%* *
+%************************************************************************
+
+\begin{code}
+instance (NamedThing name, Outputable name) => Outputable (UfExpr name) where
+ ppr e = pprUfExpr noParens e
+
+
+-- Small-hack alert: this instance allows us to do a getOccName on RdrNames.
+-- Important because we want to pretty-print UfExprs, and we have to
+-- print an '@' before tyvar-binders in a case alternative.
+instance NamedThing RdrName where
+ getOccName n = rdrNameOcc n
+ getName n = pprPanic "instance NamedThing RdrName" (ppr n)
+
+noParens :: SDoc -> SDoc
+noParens pp = pp
+
+pprUfExpr :: (NamedThing name, Outputable name) => (SDoc -> SDoc) -> UfExpr name -> SDoc
+ -- The function adds parens in context that need
+ -- an atomic value (e.g. function args)
+
+pprUfExpr add_par (UfVar v) = ppr v
+pprUfExpr add_par (UfLit l) = ppr l
+pprUfExpr add_par (UfLitLit l ty) = add_par (hsep [ptext SLIT("__litlit"), pprHsString l, pprParendHsType ty])
+pprUfExpr add_par (UfFCall cc ty) = braces (ppr cc <+> ppr ty)
+pprUfExpr add_par (UfType ty) = char '@' <+> pprParendHsType ty
+
+pprUfExpr add_par e@(UfLam _ _) = add_par (char '\\' <+> hsep (map ppr bndrs)
+ <+> ptext SLIT("->") <+> pprUfExpr noParens body)
+ where (bndrs,body) = collectUfBndrs e
+pprUfExpr add_par app@(UfApp _ _) = add_par (pprUfApp app)
+pprUfExpr add_par (UfTuple c as) = hsTupParens c (interpp'SP as)
+
+pprUfExpr add_par (UfCase scrut bndr alts)
+ = add_par (hsep [ptext SLIT("case"), pprUfExpr noParens scrut, ptext SLIT("of"), ppr bndr,
+ braces (hsep (map pp_alt alts))])
where
- pp_alts (UfCoAlgAlts alts deflt)
- = ppCat [ppInterleave ppSemi (map pp_alt alts), pp_deflt deflt]
- where
- pp_alt (c,bs,rhs) = ppCat [ppr sty c, ppr sty bs, ppStr "->", ppr sty rhs]
- pp_alts (UfCoPrimAlts alts deflt)
- = ppCat [ppInterleave ppSemi (map pp_alt alts), pp_deflt deflt]
- where
- pp_alt (l,rhs) = ppCat [ppr sty l, ppStr "->", ppr sty rhs]
+ pp_alt (UfTupleAlt tup_con, bs, rhs) = hsTupParens tup_con (interpp'SP bs) <+> ppr_rhs rhs
+ pp_alt (c, bs, rhs) = ppr c <+> hsep (map pp_bndr bs) <+> ppr_rhs rhs
+
+ ppr_rhs rhs = ptext SLIT("->") <+> pprUfExpr noParens rhs <> semi
- pp_deflt UfCoNoDefault = ppNil
- pp_deflt (UfCoBindDefault b rhs) = ppCat [ppr sty b, ppStr "->", ppr sty rhs]
+ -- This use of getOccName is the sole reason for the NamedThing in pprUfExpr's type
+ pp_bndr v | isTvOcc (getOccName v) = char '@' <+> ppr v
+ | otherwise = ppr v
- ppr sty (UfLet (UfCoNonRec b rhs) body)
- = ppCat [ppStr "let", ppr sty b, ppEquals, ppr sty rhs, ppStr "in", ppr sty body]
- ppr sty (UfLet (UfCoRec pairs) body)
- = ppCat [ppStr "letrec {", ppInterleave ppSemi (map pp_pair pairs), ppStr "} in", ppr sty body]
+pprUfExpr add_par (UfLet (UfNonRec b rhs) body)
+ = add_par (hsep [ptext SLIT("let"),
+ braces (ppr b <+> equals <+> pprUfExpr noParens rhs),
+ ptext SLIT("in"), pprUfExpr noParens body])
+
+pprUfExpr add_par (UfLet (UfRec pairs) body)
+ = add_par (hsep [ptext SLIT("__letrec"), braces (hsep (map pp_pair pairs)),
+ ptext SLIT("in"), pprUfExpr noParens body])
where
- pp_pair (b,rhs) = ppCat [ppr sty b, ppEquals, ppr sty rhs]
-
- ppr sty (UfSCC uf_cc body)
- = ppCat [ppStr "_scc_ <cost-centre[ToDo]>", ppr sty body]
-
-instance Outputable name => Outputable (UnfoldingPrimOp name) where
- ppr sty (UfCCallOp str is_casm can_gc arg_tys result_ty)
- = let
- before = ppStr (if is_casm then "_casm_ ``" else "_ccall_ ")
- after = if is_casm then ppStr "'' " else ppSP
- in
- ppBesides [before, ppPStr str, after,
- ppLbrack, ppr sty arg_tys, ppRbrack, ppSP, ppr sty result_ty]
- ppr sty (UfOtherOp op)
- = ppr sty op
-
-instance Outputable name => Outputable (UnfoldingCoreAtom name) where
- ppr sty (UfCoVarAtom v) = pprUfId sty v
- ppr sty (UfCoLitAtom l) = ppr sty l
-
-pprUfId sty (BoringUfId v) = ppr sty v
-pprUfId sty (SuperDictSelUfId c sc)
- = ppBesides [ppStr "({-superdict-}", ppr sty c, ppSP, ppr sty sc, ppStr ")"]
-pprUfId sty (ClassOpUfId c op)
- = ppBesides [ppStr "({-method-}", ppr sty c, ppSP, ppr sty op, ppStr ")"]
-pprUfId sty (DictFunUfId c ty)
- = ppBesides [ppStr "({-dfun-}", ppr sty c, ppSP, ppr sty ty, ppStr ")"]
-pprUfId sty (ConstMethodUfId c op ty)
- = ppBesides [ppStr "({-constm-}", ppr sty c, ppSP, ppr sty op, ppSP, ppr sty ty, ppStr ")"]
-pprUfId sty (DefaultMethodUfId c ty)
- = ppBesides [ppStr "({-defm-}", ppr sty c, ppSP, ppr sty ty, ppStr ")"]
-
-pprUfId sty (SpecUfId unspec ty_maybes)
- = ppBesides [ppStr "({-spec-} ", pprUfId sty unspec,
- ppInterleave ppSP (map pp_ty_maybe ty_maybes), ppStr ")"]
+ pp_pair (b,rhs) = ppr b <+> equals <+> pprUfExpr noParens rhs <> semi
+
+pprUfExpr add_par (UfNote note body) = add_par (ppr note <+> pprUfExpr parens body)
+
+pprUfApp (UfApp fun arg) = pprUfApp fun <+> pprUfExpr parens arg
+pprUfApp fun = pprUfExpr parens fun
+
+collectUfBndrs :: UfExpr name -> ([UfBinder name], UfExpr name)
+collectUfBndrs expr
+ = go [] expr
where
- pp_ty_maybe Nothing = ppStr "_N_"
- pp_ty_maybe (Just t) = ppr sty t
+ go bs (UfLam b e) = go (b:bs) e
+ go bs e = (reverse bs, e)
+
+instance Outputable name => Outputable (UfNote name) where
+ ppr (UfSCC cc) = pprCostCentreCore cc
+ ppr (UfCoerce ty) = ptext SLIT("__coerce") <+> pprParendHsType ty
+ ppr UfInlineCall = ptext SLIT("__inline_call")
+ ppr UfInlineMe = ptext SLIT("__inline_me")
+
+instance Outputable name => Outputable (UfConAlt name) where
+ ppr UfDefault = text "__DEFAULT"
+ ppr (UfLitAlt l) = ppr l
+ ppr (UfLitLitAlt l ty) = parens (hsep [ptext SLIT("__litlit"), pprHsString l, pprParendHsType ty])
+ ppr (UfDataAlt d) = ppr d
+
+instance Outputable name => Outputable (UfBinder name) where
+ ppr (UfValBinder name ty) = hsep [ppr name, dcolon, pprParendHsType ty]
+ ppr (UfTyBinder name kind) = char '@' <+> pprHsTyVarBndr name kind
+\end{code}
+
-pprUfId sty (WorkerUfId unwrkr)
- = ppBesides [ppStr "({-wrkr-}", pprUfId sty unwrkr, ppStr ")"]
+%************************************************************************
+%* *
+\subsection[HsCore-print]{Equality, for interface file checking
+%* *
+%************************************************************************
+
+ ----------------------------------------
+ HACK ALERT
+ ----------------------------------------
+
+Whe comparing UfExprs, we compare names by converting to RdrNames and comparing
+those. Reason: this is used when comparing ufoldings in interface files, and the
+uniques can differ. Converting to RdrNames makes it more like comparing the file
+contents directly. But this is bad: version numbers can change when only alpha-conversion
+has happened.
+
+ The hack shows up in eq_ufVar
+ There are corresponding getOccName calls in MkIface.diffDecls
+
+ ----------------------------------------
+ END OF HACK ALERT
+ ----------------------------------------
+
+
+\begin{code}
+instance (NamedThing name, Ord name) => Eq (UfExpr name) where
+ (==) a b = eq_ufExpr emptyEqHsEnv a b
+
+-----------------
+eq_ufBinder env (UfValBinder n1 t1) (UfValBinder n2 t2) k
+ = eq_hsType env t1 t2 && k (extendEqHsEnv env n1 n2)
+eq_ufBinder env (UfTyBinder n1 k1) (UfTyBinder n2 k2) k
+ = k1==k2 && k (extendEqHsEnv env n1 n2)
+eq_ufBinder _ _ _ _ = False
+
+-----------------
+eq_ufBinders env [] [] k = k env
+eq_ufBinders env (b1:bs1) (b2:bs2) k = eq_ufBinder env b1 b2 (\env -> eq_ufBinders env bs1 bs2 k)
+eq_ufBinders env _ _ _ = False
+
+-----------------
+eq_ufVar :: (NamedThing name, Ord name) => EqHsEnv name -> name -> name -> Bool
+-- Compare *Rdr* names. A real hack to avoid gratuitous
+-- differences when comparing interface files
+eq_ufVar env n1 n2 = case lookupFM env n1 of
+ Just n1 -> toRdrName n1 == toRdrName n2
+ Nothing -> toRdrName n1 == toRdrName n2
+
+
+-----------------
+eq_ufExpr :: (NamedThing name, Ord name) => EqHsEnv name -> UfExpr name -> UfExpr name -> Bool
+eq_ufExpr env (UfVar v1) (UfVar v2) = eq_ufVar env v1 v2
+eq_ufExpr env (UfLit l1) (UfLit l2) = l1 == l2
+eq_ufExpr env (UfLitLit l1 ty1) (UfLitLit l2 ty2) = l1==l2 && eq_hsType env ty1 ty2
+eq_ufExpr env (UfFCall c1 ty1) (UfFCall c2 ty2) = c1==c2 && eq_hsType env ty1 ty2
+eq_ufExpr env (UfType ty1) (UfType ty2) = eq_hsType env ty1 ty2
+eq_ufExpr env (UfTuple n1 as1) (UfTuple n2 as2) = n1==n2 && eqListBy (eq_ufExpr env) as1 as2
+eq_ufExpr env (UfLam b1 body1) (UfLam b2 body2) = eq_ufBinder env b1 b2 (\env -> eq_ufExpr env body1 body2)
+eq_ufExpr env (UfApp f1 a1) (UfApp f2 a2) = eq_ufExpr env f1 f2 && eq_ufExpr env a1 a2
+
+eq_ufExpr env (UfCase s1 b1 as1) (UfCase s2 b2 as2)
+ = eq_ufExpr env s1 s2 &&
+ eqListBy (eq_ufAlt (extendEqHsEnv env b1 b2)) as1 as2
+ where
+ eq_ufAlt env (c1,bs1,r1) (c2,bs2,r2)
+ = eq_ufConAlt env c1 c2 && eq_hsVars env bs1 bs2 (\env -> eq_ufExpr env r1 r2)
+
+eq_ufExpr env (UfLet (UfNonRec b1 r1) x1) (UfLet (UfNonRec b2 r2) x2)
+ = eq_ufExpr env r1 r2 && eq_ufBinder env b1 b2 (\env -> eq_ufExpr env x1 x2)
+
+eq_ufExpr env (UfLet (UfRec as1) x1) (UfLet (UfRec as2) x2)
+ = eq_ufBinders env bs1 bs2 (\env -> eqListBy (eq_ufExpr env) rs1 rs2 && eq_ufExpr env x1 x2)
+ where
+ (bs1,rs1) = unzip as1
+ (bs2,rs2) = unzip as2
+
+eq_ufExpr env (UfNote n1 r1) (UfNote n2 r2)
+ = eq_ufNote n1 n2 && eq_ufExpr env r1 r2
+ where
+ eq_ufNote (UfSCC c1) (UfSCC c2) = c1==c2
+ eq_ufNote (UfCoerce t1) (UfCoerce t2) = eq_hsType env t1 t2
+ eq_ufNote UfInlineCall UfInlineCall = True
+ eq_ufNote UfInlineMe UfInlineMe = True
+ eq_ufNote _ _ = False
+
+eq_ufExpr env _ _ = False
+
+-----------------
+eq_ufConAlt env UfDefault UfDefault = True
+eq_ufConAlt env (UfDataAlt n1) (UfDataAlt n2) = n1==n2
+eq_ufConAlt env (UfTupleAlt c1) (UfTupleAlt c2) = c1==c2
+eq_ufConAlt env (UfLitAlt l1) (UfLitAlt l2) = l1==l2
+eq_ufConAlt env (UfLitLitAlt s1 t1) (UfLitLitAlt s2 t2) = s1==s2 && eq_hsType env t1 t2
+eq_ufConAlt env _ _ = False
+\end{code}
+
+
+%************************************************************************
+%* *
+\subsection{Rules in interface files}
+%* *
+%************************************************************************
+
+\begin{code}
+pprHsIdInfo :: (NamedThing n, Outputable n) => [HsIdInfo n] -> SDoc
+pprHsIdInfo [] = empty
+pprHsIdInfo info = ptext SLIT("{-##") <+> hsep (map ppr_hs_info info) <+> ptext SLIT("##-}")
+
+data HsIdInfo name
+ = HsArity Arity
+ | HsStrictness StrictnessInfo
+ | HsUnfold InlinePragInfo (UfExpr name)
+ | HsNoCafRefs
+ | HsCprInfo
+ | HsWorker name Arity -- Worker, if any see IdInfo.WorkerInfo
+ -- for why we want arity here.
+ deriving( Eq )
+-- NB: Specialisations and rules come in separately and are
+-- only later attached to the Id. Partial reason: some are orphans.
+
+ppr_hs_info (HsUnfold prag unf) = ptext SLIT("__U") <> pprInlinePragInfo prag <+> parens (pprUfExpr noParens unf)
+ppr_hs_info (HsArity arity) = ptext SLIT("__A") <+> int arity
+ppr_hs_info (HsStrictness str) = ptext SLIT("__S") <+> ppStrictnessInfo str
+ppr_hs_info HsNoCafRefs = ptext SLIT("__C")
+ppr_hs_info HsCprInfo = ptext SLIT("__M")
+ppr_hs_info (HsWorker w a) = ptext SLIT("__P") <+> ppr w <+> int a
\end{code}