X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;ds=sidebyside;f=ghc%2Fcompiler%2Ftypecheck%2FTcDeriv.lhs;h=86084ab89af5884ed759c79b4e31ac9aa49ac470;hb=486c94ae36e36c341cf607a8bda3241ba90bf538;hp=80d6b10c2c99ae6b39dde285c52c1bf264b1bb42;hpb=f1080bc82f87317ffa59cffef08b322d7354bb29;p=ghc-hetmet.git diff --git a/ghc/compiler/typecheck/TcDeriv.lhs b/ghc/compiler/typecheck/TcDeriv.lhs index 80d6b10..86084ab 100644 --- a/ghc/compiler/typecheck/TcDeriv.lhs +++ b/ghc/compiler/typecheck/TcDeriv.lhs @@ -10,50 +10,48 @@ module TcDeriv ( tcDeriving ) where #include "HsVersions.h" -import HsSyn ( HsBinds(..), MonoBinds(..), collectLocatedMonoBinders ) +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(..), pprInstInfo, simpleDFunClassTyCon, extendInstEnv ) +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 Type ( TauType, ThetaType, PredType, mkTyVarTys, mkTyConApp, + isUnLiftedType, mkClassPred ) import Var ( TyVar ) import PrelNames -import Bag ( bagToList ) -import Util ( zipWithEqual, sortLt, thenCmp ) +import Util ( zipWithEqual, sortLt ) import ListSetOps ( removeDups, assoc ) import Outputable +import List ( nub ) \end{code} %************************************************************************ @@ -145,8 +143,7 @@ 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 = [(Class, [TauType])] -- Same as a ThetaType! - +type DerivRhs = ThetaType type DerivSoln = DerivRhs \end{code} @@ -185,15 +182,17 @@ context to the instance decl. The "offending classes" are 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 prs mod inst_env_in local_tycons +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 local_tycons `thenTc` \ eqns -> + makeDerivEqns tycl_decls `thenTc` \ eqns -> if null eqns then returnTc ([], EmptyBinds) else @@ -212,27 +211,29 @@ tcDeriving prs mod inst_env_in local_tycons 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 (tcGST env)) new_dfuns + 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 prs ( + = 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_dfuns `zip` rn_method_binds_s) `thenNF_Tc` \ new_inst_infos -> - ioToTc (dumpIfSet opt_D_dump_deriv "Derived instances" - (ddump_deriving 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 (new_inst_infos, rn_extra_binds) where @@ -242,15 +243,10 @@ tcDeriving prs mod inst_env_in local_tycons where -- Make a Real dfun instead of the dummy one we have so far - gen_inst_info (dfun, binds) - = InstInfo { iLocal = True, - iClass = clas, iTyVars = tyvars, - iTys = tys, iTheta = theta, - iDFunId = dfun, iBinds = binds, - iLoc = getSrcLoc dfun, iPrags = [] } - where - (tyvars, theta, tau) = splitSigmaTy dfun - (clas, tys) = splitDictTy tau + 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 @@ -279,66 +275,57 @@ or} has just one data constructor (e.g., tuples). all those. \begin{code} -makeDerivEqns :: Module -> [TyCon] -> TcM [DerivEqn] +makeDerivEqns :: [RenamedTyClDecl] -> TcM [DerivEqn] -makeDerivEqns this_mod local_tycons - = let - think_about_deriving = need_deriving local_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 (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_` + 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 this_mod clas tys locn `thenNF_Tc` \ dfun_name -> + Nothing -> newDFunName clas [ty] locn `thenNF_Tc` \ dfun_name -> returnNF_Tc (Just (dfun_name, 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 - offensive_class = clas_key `elem` needsDataDeclCtxtClassKeys - 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 @@ -401,7 +388,8 @@ solveDerivEqns inst_env_in orig_eqns -- It fails if any iteration fails iterateDeriv :: [DerivSoln] ->TcM [DFunId] iterateDeriv current_solns - = checkNoErrsTc (iterateOnce current_solns) `thenTc` \ (new_dfuns, new_solns) -> + = checkNoErrsTc (iterateOnce current_solns) + `thenTc` \ (new_dfuns, new_solns) -> if (current_solns == new_solns) then returnTc new_dfuns else @@ -411,15 +399,17 @@ solveDerivEqns inst_env_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_env_in orig_eqns current_solns `thenNF_Tc` \ (new_dfuns, 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 -> + ) `thenTc` \ next_solns -> -- Canonicalise the solutions, so they compare nicely let canonicalised_next_solns = [ sortLt (<) next_soln | next_soln <- next_solns ] @@ -428,23 +418,26 @@ solveDerivEqns inst_env_in orig_eqns \end{code} \begin{code} -add_solns :: InstEnv -- The global, non-derived ones +add_solns :: DynFlags + -> InstEnv -- The global, non-derived ones -> [DerivEqn] -> [DerivSoln] -> ([DFunId], InstEnv) -- the eqns and solns move "in lockstep"; we have the eqns -- because we need the LHS info for addClassInstance. -add_solns inst_env_in eqns solns +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 inst_env_in + 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 + mk_deriv_dfun (dfun_name, clas, tycon, tyvars, _) theta + = mkDictFunId dfun_name clas tyvars + [mkTyConApp tycon (mkTyVarTys tyvars)] + theta \end{code} %************************************************************************ @@ -513,11 +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 :: GlobalSymbolTable -> DFunId -> RdrNameMonoBinds -gen_bind fixities inst - | not (isLocallyDefined tycon) = 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) @@ -544,7 +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: @@ -575,7 +567,7 @@ 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 = map simplDFunClassTyCon dfuns + all_CTs = map simpleDFunClassTyCon dfuns all_tycons = map snd all_CTs (tycons_of_interest, _) = removeDups compare all_tycons @@ -611,7 +603,6 @@ gen_taggery_Names dfuns 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}