X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;ds=sidebyside;f=ghc%2Fcompiler%2Ftypecheck%2FTcDeriv.lhs;h=54a8e720d500d80f37a3caaa2d3f7c4754e20648;hb=a5ded1f8e90fd3dfc0cb05767923bcb0dd7392af;hp=4d21acebb185d2d30aac9dff3d04f38f326b99f9;hpb=861e836ed0cc1aa45932ecb3470967964440a0ef;p=ghc-hetmet.git diff --git a/ghc/compiler/typecheck/TcDeriv.lhs b/ghc/compiler/typecheck/TcDeriv.lhs index 4d21ace..54a8e72 100644 --- a/ghc/compiler/typecheck/TcDeriv.lhs +++ b/ghc/compiler/typecheck/TcDeriv.lhs @@ -10,49 +10,48 @@ module TcDeriv ( tcDeriving ) where #include "HsVersions.h" -import HsSyn ( HsBinds(..), MonoBinds(..), collectMonoBinders ) +import HsSyn ( HsBinds(..), MonoBinds(..), TyClDecl(..), + collectLocatedMonoBinders ) import RdrHsSyn ( RdrNameMonoBinds ) -import RnHsSyn ( RenamedHsBinds ) -import CmdLineOpts ( opt_D_dump_deriv ) +import RnHsSyn ( RenamedHsBinds, RenamedMonoBinds, RenamedTyClDecl ) +import CmdLineOpts ( DynFlag(..), DynFlags ) import TcMonad -import TcEnv ( InstEnv, getEnvTyCons, tcSetInstEnv, newDFunName ) +import TcEnv ( tcSetInstEnv, newDFunName, InstInfo(..), pprInstInfo, + tcLookupClass, tcLookupTyCon + ) import TcGenDeriv -- Deriv stuff -import TcInstUtil ( InstInfo(..), buildInstanceEnv ) +import InstEnv ( InstEnv, simpleDFunClassTyCon, extendInstEnv ) import TcSimplify ( tcSimplifyThetas ) import RnBinds ( rnMethodBinds, rnTopMonoBinds ) import RnEnv ( bindLocatedLocalsRn ) -import RnMonad ( RnNameSupply, - renameSourceCode, thenRn, mapRn, returnRn ) +import RnMonad ( renameDerivedCode, thenRn, mapRn, returnRn ) +import HscTypes ( DFunId, PersistentRenamerState ) -import Bag ( Bag, emptyBag, unionBags, listToBag ) +import BasicTypes ( Fixity ) import Class ( classKey, Class ) -import ErrUtils ( dumpIfSet, Message ) +import ErrUtils ( dumpIfSet_dyn, Message ) import MkId ( mkDictFunId ) -import Id ( mkVanillaId ) import DataCon ( dataConArgTys, isNullaryDataCon, isExistentialDataCon ) import PrelInfo ( needsDataDeclCtxtClassKeys ) import Maybes ( maybeToBool, catMaybes ) import Module ( Module ) -import Name ( isLocallyDefined, getSrcLoc, NamedThing(..) ) +import Name ( Name, getSrcLoc ) import RdrName ( RdrName ) -import RnMonad ( FixityEnv ) -import TyCon ( tyConTyVars, tyConDataCons, tyConDerivings, +import TyCon ( tyConTyVars, tyConDataCons, tyConTheta, maybeTyConSingleCon, isDataTyCon, - isEnumerationTyCon, isAlgTyCon, TyCon - ) -import Type ( TauType, mkTyVarTys, mkTyConApp, - mkSigmaTy, mkDictTy, isUnboxedType, - splitAlgTyConApp, classesToPreds + isEnumerationTyCon, TyCon ) -import TysWiredIn ( voidTy ) +import TcType ( ThetaType, mkTyVarTys, mkTyConApp, + isUnLiftedType, mkClassPred ) import Var ( TyVar ) import PrelNames -import Bag ( bagToList ) -import Util ( zipWithEqual, sortLt, removeDups, assoc, thenCmp ) +import Util ( zipWithEqual, sortLt ) +import ListSetOps ( removeDups, assoc ) import Outputable +import List ( nub ) \end{code} %************************************************************************ @@ -140,13 +139,11 @@ this by simplifying the RHS to a form in which So, here are the synonyms for the ``equation'' structures: \begin{code} -type DerivEqn = (Class, TyCon, [TyVar], DerivRhs) - -- The tyvars bind all the variables in the RHS - -- NEW: it's convenient to re-use InstInfo - -- We'll "panic" out some fields... - -type DerivRhs = [(Class, [TauType])] -- Same as a ThetaType! +type DerivEqn = (Name, Class, TyCon, [TyVar], DerivRhs) + -- The Name is the name for the DFun we'll build + -- The tyvars bind all the variables in the RHS +type DerivRhs = ThetaType type DerivSoln = DerivRhs \end{code} @@ -182,27 +179,28 @@ context to the instance decl. The "offending classes" are %************************************************************************ \begin{code} -tcDeriving :: Module -- name of module under scrutiny - -> FixityEnv -- for the deriving code (Show/Read.) - -> RnNameSupply -- for "renaming" bits of generated code - -> Bag InstInfo -- What we already know about instances - -> TcM s (Bag InstInfo, -- The generated "instance decls". - RenamedHsBinds) -- Extra generated bindings +tcDeriving :: PersistentRenamerState + -> Module -- name of module under scrutiny + -> InstEnv -- What we already know about instances + -> (Name -> Maybe Fixity) -- used in deriving Show and Read + -> [RenamedTyClDecl] -- All type constructors + -> TcM ([InstInfo], -- The generated "instance decls". + RenamedHsBinds) -- Extra generated bindings -tcDeriving mod fixs rn_name_supply inst_decl_infos_in - = recoverTc (returnTc (emptyBag, EmptyBinds)) $ +tcDeriving prs mod inst_env_in get_fixity tycl_decls + = recoverTc (returnTc ([], EmptyBinds)) $ -- Fish the "deriving"-related information out of the TcEnv -- and make the necessary "equations". - makeDerivEqns `thenTc` \ eqns -> + makeDerivEqns tycl_decls `thenTc` \ eqns -> if null eqns then - returnTc (emptyBag, EmptyBinds) + returnTc ([], EmptyBinds) else -- Take the equation list and solve it, to deliver a list of -- solutions, a.k.a. the contexts for the instance decls -- required for the corresponding equations. - solveDerivEqns inst_decl_infos_in eqns `thenTc` \ new_inst_infos -> + solveDerivEqns inst_env_in eqns `thenTc` \ new_dfuns -> -- Now augment the InstInfos, adding in the rather boring -- actual-code-to-do-the-methods binds. We may also need to @@ -210,53 +208,47 @@ tcDeriving mod fixs rn_name_supply inst_decl_infos_in -- "con2tag" and/or "tag2con" functions. We do these -- separately. - gen_taggery_Names new_inst_infos `thenTc` \ nm_alist_etc -> - + gen_taggery_Names new_dfuns `thenTc` \ nm_alist_etc -> + tcGetEnv `thenNF_Tc` \ env -> + getDOptsTc `thenTc` \ dflags -> let extra_mbind_list = map gen_tag_n_con_monobind nm_alist_etc extra_mbinds = foldr AndMonoBinds EmptyMonoBinds extra_mbind_list - method_binds_s = map (gen_bind fixs) new_inst_infos - mbinders = bagToList (collectMonoBinders extra_mbinds) + method_binds_s = map (gen_bind get_fixity) new_dfuns + mbinders = collectLocatedMonoBinders extra_mbinds -- Rename to get RenamedBinds. -- The only tricky bit is that the extra_binds must scope over the -- method bindings for the instances. (rn_method_binds_s, rn_extra_binds) - = renameSourceCode mod rn_name_supply ( + = renameDerivedCode dflags mod prs ( bindLocatedLocalsRn (ptext (SLIT("deriving"))) mbinders $ \ _ -> rnTopMonoBinds extra_mbinds [] `thenRn` \ (rn_extra_binds, _) -> mapRn rn_meths method_binds_s `thenRn` \ rn_method_binds_s -> returnRn (rn_method_binds_s, rn_extra_binds) ) + + new_inst_infos = zipWith gen_inst_info new_dfuns rn_method_binds_s in - mapNF_Tc gen_inst_info (new_inst_infos `zip` rn_method_binds_s) `thenNF_Tc` \ really_new_inst_infos -> - ioToTc (dumpIfSet opt_D_dump_deriv "Derived instances" - (ddump_deriving really_new_inst_infos rn_extra_binds)) `thenTc_` + ioToTc (dumpIfSet_dyn dflags Opt_D_dump_deriv "Derived instances" + (ddump_deriving new_inst_infos rn_extra_binds)) `thenTc_` - returnTc (listToBag really_new_inst_infos, rn_extra_binds) + returnTc (new_inst_infos, rn_extra_binds) where ddump_deriving :: [InstInfo] -> RenamedHsBinds -> SDoc ddump_deriving inst_infos extra_binds - = vcat (map pp_info inst_infos) $$ ppr extra_binds + = vcat (map pprInstInfo inst_infos) $$ ppr extra_binds where - pp_info (InstInfo clas tvs [ty] inst_decl_theta _ mbinds _ _) - = ppr (mkSigmaTy tvs inst_decl_theta' (mkDictTy clas [ty])) - $$ - ppr mbinds - where inst_decl_theta' = classesToPreds inst_decl_theta - - -- Paste the dfun id and method binds into the InstInfo - gen_inst_info (InstInfo clas tyvars tys@(ty:_) inst_decl_theta _ _ locn _, meth_binds) - = newDFunName mod clas tys locn `thenNF_Tc` \ dfun_name -> - let - dfun_id = mkDictFunId dfun_name clas tyvars tys inst_decl_theta - in - returnNF_Tc (InstInfo clas tyvars tys inst_decl_theta - dfun_id meth_binds locn []) - rn_meths meths = rnMethodBinds meths `thenRn` \ (meths', _) -> returnRn meths' + -- Make a Real dfun instead of the dummy one we have so far + gen_inst_info :: DFunId -> RenamedMonoBinds -> InstInfo + gen_inst_info dfun binds + = InstInfo { iDFunId = dfun, + iBinds = binds, iPrags = [] } + + rn_meths meths = rnMethodBinds [] meths `thenRn` \ (meths', _) -> returnRn meths' -- Ignore the free vars returned \end{code} @@ -283,69 +275,57 @@ or} has just one data constructor (e.g., tuples). all those. \begin{code} -makeDerivEqns :: TcM s [DerivEqn] - -makeDerivEqns - = tcGetEnv `thenNF_Tc` \ env -> - let - local_data_tycons = filter (\tc -> isLocallyDefined tc && isAlgTyCon tc) - (getEnvTyCons env) +makeDerivEqns :: [RenamedTyClDecl] -> TcM [DerivEqn] - think_about_deriving = need_deriving local_data_tycons - (derive_these, _) = removeDups cmp_deriv think_about_deriving - in - if null local_data_tycons then - returnTc [] -- Bale out now - else - mapTc mk_eqn derive_these `thenTc` \ maybe_eqns -> +makeDerivEqns tycl_decls + = mapTc mk_eqn derive_these `thenTc` \ maybe_eqns -> returnTc (catMaybes maybe_eqns) where ------------------------------------------------------------------ - need_deriving :: [TyCon] -> [(Class, TyCon)] - -- find the tycons that have `deriving' clauses; - - need_deriving tycons_to_consider - = foldr (\ tycon acc -> [(clas,tycon) | clas <- tyConDerivings tycon] ++ acc) - [] - tycons_to_consider + derive_these :: [(Name, Name)] + -- Find the (Class,TyCon) pairs that must be `derived' + -- NB: only source-language decls have deriving, no imported ones do + derive_these = [ (clas,tycon) + | TyData {tcdName = tycon, tcdDerivs = Just classes} <- tycl_decls, + clas <- nub classes ] ------------------------------------------------------------------ - cmp_deriv :: (Class, TyCon) -> (Class, TyCon) -> Ordering - cmp_deriv (c1, t1) (c2, t2) - = (c1 `compare` c2) `thenCmp` (t1 `compare` t2) - - ------------------------------------------------------------------ - mk_eqn :: (Class, TyCon) -> NF_TcM s (Maybe DerivEqn) + mk_eqn :: (Name, Name) -> NF_TcM (Maybe DerivEqn) -- we swizzle the tyvars and datacons out of the tycon -- to make the rest of the equation - mk_eqn (clas, tycon) - = case chk_out clas tycon of - Just err -> addErrTc err `thenNF_Tc_` - returnNF_Tc Nothing - Nothing -> returnNF_Tc (Just (clas, tycon, tyvars, constraints)) - where - clas_key = classKey clas - tyvars = tyConTyVars tycon -- ToDo: Do we need new tyvars ??? - tyvar_tys = mkTyVarTys tyvars - data_cons = tyConDataCons tycon - - constraints = extra_constraints ++ concat (map mk_constraints data_cons) - - -- "extra_constraints": see notes above about contexts on data decls - extra_constraints - | offensive_class = tyConTheta tycon - | otherwise = [] - where + mk_eqn (clas_name, tycon_name) + = tcLookupClass clas_name `thenNF_Tc` \ clas -> + tcLookupTyCon tycon_name `thenNF_Tc` \ tycon -> + let + clas_key = classKey clas + tyvars = tyConTyVars tycon + tyvar_tys = mkTyVarTys tyvars + ty = mkTyConApp tycon tyvar_tys + data_cons = tyConDataCons tycon + locn = getSrcLoc tycon + constraints = extra_constraints ++ concat (map mk_constraints data_cons) + + -- "extra_constraints": see notes above about contexts on data decls + extra_constraints + | offensive_class = tyConTheta tycon + | otherwise = [] + offensive_class = clas_key `elem` needsDataDeclCtxtClassKeys + + mk_constraints data_con + = [ mkClassPred clas [arg_ty] + | arg_ty <- dataConArgTys data_con tyvar_tys, + not (isUnLiftedType arg_ty) -- No constraints for unlifted types? + ] + in + case chk_out clas tycon of + Just err -> addErrTc err `thenNF_Tc_` + returnNF_Tc Nothing + Nothing -> newDFunName clas [ty] locn `thenNF_Tc` \ dfun_name -> + returnNF_Tc (Just (dfun_name, clas, tycon, tyvars, constraints)) + - mk_constraints data_con - = [ (clas, [arg_ty]) - | arg_ty <- instd_arg_tys, - not (isUnboxedType arg_ty) -- No constraints for unboxed types? - ] - where - instd_arg_tys = dataConArgTys data_con tyvar_tys ------------------------------------------------------------------ chk_out :: Class -> TyCon -> Maybe Message @@ -387,12 +367,12 @@ ordered by sorting on type varible, tv, (major key) and then class, k, \end{itemize} \begin{code} -solveDerivEqns :: Bag InstInfo +solveDerivEqns :: InstEnv -> [DerivEqn] - -> TcM s [InstInfo] -- Solns in same order as eqns. - -- This bunch is Absolutely minimal... + -> TcM [DFunId] -- Solns in same order as eqns. + -- This bunch is Absolutely minimal... -solveDerivEqns inst_decl_infos_in orig_eqns +solveDerivEqns inst_env_in orig_eqns = iterateDeriv initial_solutions where -- The initial solutions for the equations claim that each @@ -406,11 +386,12 @@ solveDerivEqns inst_decl_infos_in orig_eqns -- compares it with the current one; finishes if they are the -- same, otherwise recurses with the new solutions. -- It fails if any iteration fails - iterateDeriv :: [DerivSoln] ->TcM s [InstInfo] + iterateDeriv :: [DerivSoln] ->TcM [DFunId] iterateDeriv current_solns - = checkNoErrsTc (iterateOnce current_solns) `thenTc` \ (new_inst_infos, new_solns) -> + = checkNoErrsTc (iterateOnce current_solns) + `thenTc` \ (new_dfuns, new_solns) -> if (current_solns == new_solns) then - returnTc new_inst_infos + returnTc new_dfuns else iterateDeriv new_solns @@ -418,71 +399,45 @@ solveDerivEqns inst_decl_infos_in orig_eqns iterateOnce current_solns = -- Extend the inst info from the explicit instance decls -- with the current set of solutions, giving a - - add_solns inst_decl_infos_in orig_eqns current_solns - `thenNF_Tc` \ (new_inst_infos, inst_env) -> - + getDOptsTc `thenTc` \ dflags -> + let (new_dfuns, inst_env) = + add_solns dflags inst_env_in orig_eqns current_solns + in -- Simplify each RHS - tcSetInstEnv inst_env ( - listTc [ tcAddErrCtxt (derivCtxt tc) $ + listTc [ tcAddSrcLoc (getSrcLoc tc) $ + tcAddErrCtxt (derivCtxt tc) $ tcSimplifyThetas deriv_rhs - | (_,tc,_,deriv_rhs) <- orig_eqns ] - ) `thenTc` \ next_solns -> + | (_, _,tc,_,deriv_rhs) <- orig_eqns ] + ) `thenTc` \ next_solns -> -- Canonicalise the solutions, so they compare nicely - let canonicalised_next_solns - = [ sortLt (<) next_soln | next_soln <- next_solns ] + let canonicalised_next_solns = [ sortLt (<) next_soln | next_soln <- next_solns ] in - returnTc (new_inst_infos, canonicalised_next_solns) + returnTc (new_dfuns, canonicalised_next_solns) \end{code} \begin{code} -add_solns :: Bag InstInfo -- The global, non-derived ones +add_solns :: DynFlags + -> InstEnv -- The global, non-derived ones -> [DerivEqn] -> [DerivSoln] - -> NF_TcM s ([InstInfo], -- The new, derived ones - InstEnv) + -> ([DFunId], InstEnv) -- the eqns and solns move "in lockstep"; we have the eqns -- because we need the LHS info for addClassInstance. -add_solns inst_infos_in eqns solns - - = discardErrsTc (buildInstanceEnv all_inst_infos) `thenNF_Tc` \ inst_env -> - -- We do the discard-errs so that we don't get repeated error messages - -- about duplicate instances. - -- They'll appear later, when we do the top-level buildInstanceEnv. - - returnNF_Tc (new_inst_infos, inst_env) - where - new_inst_infos = zipWithEqual "add_solns" mk_deriv_inst_info eqns solns - - all_inst_infos = inst_infos_in `unionBags` listToBag new_inst_infos - - mk_deriv_inst_info (clas, tycon, tyvars, _) theta - = InstInfo clas tyvars [mkTyConApp tycon (mkTyVarTys tyvars)] - theta - dummy_dfun_id - (my_panic "binds") (getSrcLoc tycon) - (my_panic "upragmas") - where - dummy_dfun_id - = mkVanillaId (getName tycon) dummy_dfun_ty - -- The name is getSrcLoc'd in an error message - - theta' = classesToPreds theta - dummy_dfun_ty = mkSigmaTy tyvars theta' voidTy - -- All we need from the dfun is its "theta" part, used during - -- equation simplification (tcSimplifyThetas). The final - -- dfun_id will have the superclass dictionaries as arguments too, - -- but that'll be added after the equations are solved. For now, - -- it's enough just to make a dummy dfun with the simple theta part. - -- - -- The part after the theta is dummied here as voidTy; actually it's - -- (C (T a b)), but it doesn't seem worth constructing it. - -- We can't leave it as a panic because to get the theta part we - -- have to run down the type! - - my_panic str = panic "add_soln" -- pprPanic ("add_soln:"++str) (hsep [char ':', ppr clas, ppr tycon]) +add_solns dflags inst_env_in eqns solns + = (new_dfuns, inst_env) + where + new_dfuns = zipWithEqual "add_solns" mk_deriv_dfun eqns solns + (inst_env, _) = extendInstEnv dflags inst_env_in new_dfuns + -- Ignore the errors about duplicate instances. + -- We don't want repeated error messages + -- They'll appear later, when we do the top-level extendInstEnvs + + mk_deriv_dfun (dfun_name, clas, tycon, tyvars, _) theta + = mkDictFunId dfun_name clas tyvars + [mkTyConApp tycon (mkTyVarTys tyvars)] + theta \end{code} %************************************************************************ @@ -551,11 +506,10 @@ the renamer. What a great hack! -- Generate the method bindings for the required instance -- (paired with class name, as we need that when generating dict -- names.) -gen_bind :: FixityEnv -> InstInfo -> RdrNameMonoBinds -gen_bind fixities (InstInfo clas _ [ty] _ _ _ _ _) - | not from_here = EmptyMonoBinds - | clas `hasKey` showClassKey = gen_Show_binds fixities tycon - | clas `hasKey` readClassKey = gen_Read_binds fixities tycon +gen_bind :: (Name -> Maybe Fixity) -> DFunId -> RdrNameMonoBinds +gen_bind get_fixity dfun + | clas `hasKey` showClassKey = gen_Show_binds get_fixity tycon + | clas `hasKey` readClassKey = gen_Read_binds get_fixity tycon | otherwise = assoc "gen_bind:bad derived class" [(eqClassKey, gen_Eq_binds) @@ -567,8 +521,7 @@ gen_bind fixities (InstInfo clas _ [ty] _ _ _ _ _) (classKey clas) tycon where - from_here = isLocallyDefined tycon - (tycon,_,_) = splitAlgTyConApp ty + (clas, tycon) = simpleDFunClassTyCon dfun \end{code} @@ -583,7 +536,7 @@ data Foo ... = ... con2tag_Foo :: Foo ... -> Int# tag2con_Foo :: Int -> Foo ... -- easier if Int, not Int# -maxtag_Foo :: Int -- ditto (NB: not unboxed) +maxtag_Foo :: Int -- ditto (NB: not unlifted) We have a @con2tag@ function for a tycon if: @@ -605,21 +558,17 @@ We're deriving @Enum@, or @Ix@ (enum type only???) If we have a @tag2con@ function, we also generate a @maxtag@ constant. \begin{code} -gen_taggery_Names :: [InstInfo] - -> TcM s [(RdrName, -- for an assoc list - TyCon, -- related tycon - TagThingWanted)] - -gen_taggery_Names inst_infos - = --pprTrace "gen_taggery:\n" (vcat [hsep [ppr c, ppr t] | (c,t) <- all_CTs]) $ - foldlTc do_con2tag [] tycons_of_interest `thenTc` \ names_so_far -> +gen_taggery_Names :: [DFunId] + -> TcM [(RdrName, -- for an assoc list + TyCon, -- related tycon + TagThingWanted)] + +gen_taggery_Names dfuns + = foldlTc do_con2tag [] tycons_of_interest `thenTc` \ names_so_far -> foldlTc do_tag2con names_so_far tycons_of_interest where - all_CTs = [ (c, get_tycon ty) | (InstInfo c _ [ty] _ _ _ _ _) <- inst_infos ] - - get_tycon ty = case splitAlgTyConApp ty of { (tc, _, _) -> tc } - - all_tycons = map snd all_CTs + all_CTs = map simpleDFunClassTyCon dfuns + all_tycons = map snd all_CTs (tycons_of_interest, _) = removeDups compare all_tycons do_con2tag acc_Names tycon @@ -654,7 +603,6 @@ gen_taggery_Names inst_infos is_in_eqns clas_key tycon ((c,t):cts) = (clas_key == classKey c && tycon == t) || is_in_eqns clas_key tycon cts - \end{code} \begin{code}