X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Frename%2FRnIfaces.lhs;h=e3aa3a42911a190a02d3a8b19f7ed92fa2f6786a;hb=7d71bf0b4e294a7cb62037aedd087519ead9ade8;hp=797e1804a003d39e8f69277a0c388b7ec473eee1;hpb=5dd916543a04bd22de43c242cb0a0c14aafc90f3;p=ghc-hetmet.git diff --git a/ghc/compiler/rename/RnIfaces.lhs b/ghc/compiler/rename/RnIfaces.lhs index 797e180..e3aa3a4 100644 --- a/ghc/compiler/rename/RnIfaces.lhs +++ b/ghc/compiler/rename/RnIfaces.lhs @@ -1,18 +1,12 @@ % % (c) The GRASP/AQUA Project, Glasgow University, 1992-1998 -% -\section[RnIfaces]{Cacheing and Renaming of Interfaces} +section +\%[RnIfaces]{Cacheing and Renaming of Interfaces} \begin{code} module RnIfaces - ( - getInterfaceExports, - recordLocalSlurps, - mkImportInfo, - - slurpImpDecls, closeDecls, - - RecompileRequired, outOfDate, upToDate, recompileRequired + ( slurpImpDecls, importSupportingDecls, + RecompileRequired, outOfDate, upToDate, checkVersions ) where @@ -20,188 +14,40 @@ where import CmdLineOpts ( opt_IgnoreIfacePragmas, opt_NoPruneDecls ) import HscTypes -import HsSyn ( HsDecl(..), Sig(..), TyClDecl(..), ConDecl(..), ConDetails(..), +import HsSyn ( HsDecl(..), Sig(..), TyClDecl(..), ConDecl(..), HsConDetails(..), InstDecl(..), HsType(..), hsTyVarNames, getBangType ) -import HsImpExp ( ImportDecl(..) ) import RdrHsSyn ( RdrNameTyClDecl, RdrNameInstDecl, RdrNameRuleDecl ) import RnHsSyn ( RenamedHsDecl, RenamedTyClDecl, extractHsTyNames, extractHsCtxtTyNames, - tyClDeclFVs, ruleDeclFVs, instDeclFVs - ) -import RnHiFiles ( tryLoadInterface, loadHomeInterface, loadInterface, - loadOrphanModules + tyClDeclFVs, ruleDeclFVs, impDeclFVs ) +import RnHiFiles ( loadInterface, loadHomeInterface, loadOrphanModules ) +import RnNames ( mkModDeps ) import RnSource ( rnTyClDecl, rnInstDecl, rnIfaceRuleDecl ) -import RnEnv -import RnMonad -import Id ( idType ) -import Type ( namesOfType ) -import TyCon ( isSynTyCon, getSynTyConDefn ) -import Name ( Name {-instance NamedThing-}, nameOccName, - nameModule, isLocalName, nameUnique, - NamedThing(..) - ) -import Name ( elemNameEnv, delFromNameEnv ) -import Module ( Module, ModuleEnv, - moduleName, isModuleInThisPackage, - ModuleName, WhereFrom(..), - emptyModuleEnv, - extendModuleEnv_C, foldModuleEnv, lookupModuleEnv, - elemModuleSet, extendModuleSet - ) +import TcEnv ( getInGlobalScope, tcLookupGlobal_maybe ) +import TcRnMonad +import Id ( idType, idName, globalIdDetails ) +import IdInfo ( GlobalIdDetails(..) ) +import TcType ( tyClsNamesOfType, classNamesOfTheta ) +import FieldLabel ( fieldLabelTyCon ) +import DataCon ( dataConTyCon, dataConWrapId ) +import TyCon ( visibleDataCons, isSynTyCon, getSynTyConDefn, tyConClass_maybe, tyConName ) +import Class ( className, classSCTheta ) +import Name ( Name {-instance NamedThing-}, isWiredInName, nameIsLocalOrFrom, + nameModule, NamedThing(..) ) +import NameEnv ( delFromNameEnv, lookupNameEnv ) import NameSet -import PrelInfo ( wiredInThingEnv, fractionalClassKeys ) -import TysWiredIn ( doubleTyCon ) -import Maybes ( orElse ) -import FiniteMap +import Module ( Module, isHomeModule ) +import PrelNames ( hasKey, fractionalClassKey, numClassKey, + integerTyConName, doubleTyConName ) import Outputable import Bag -import Util ( sortLt ) +import Maybe( fromJust ) \end{code} %********************************************************* -%* * -\subsection{Getting what a module exports} -%* * -%********************************************************* - -@getInterfaceExports@ is called only for directly-imported modules. - -\begin{code} -getInterfaceExports :: ModuleName -> WhereFrom -> RnMG (Module, [(ModuleName,Avails)]) -getInterfaceExports mod_name from - = loadInterface doc_str mod_name from `thenRn` \ iface -> - returnRn (mi_module iface, mi_exports iface) - where - doc_str = sep [ppr mod_name, ptext SLIT("is directly imported")] -\end{code} - - -%********************************************************* -%* * -\subsection{Keeping track of what we've slurped, and version numbers} -%* * -%********************************************************* - -mkImportInof figures out what the ``usage information'' for this -moudule is; that is, what it must record in its interface file as the -things it uses. - -We produce a line for every module B below the module, A, currently being -compiled: - import B ; -to record the fact that A does import B indireclty. This is used to decide -to look to look for B.hi rather than B.hi-boot when compiling a module that -imports A. This line says that A imports B, but uses nothing in it. -So we'll get an early bale-out when compiling A if B's version changes. - -\begin{code} -mkImportInfo :: ModuleName -- Name of this module - -> [ImportDecl n] -- The import decls - -> RnMG [ImportVersion Name] - -mkImportInfo this_mod imports - = getIfacesRn `thenRn` \ ifaces -> - getHomeIfaceTableRn `thenRn` \ hit -> - let - (imp_pkg_mods, imp_home_names) = iVSlurp ifaces - pit = iPIT ifaces - - import_all_mods :: [ModuleName] - -- Modules where we imported all the names - -- (apart from hiding some, perhaps) - import_all_mods = [ m | ImportDecl m _ _ _ imp_list _ <- imports, - import_all imp_list ] - where - import_all (Just (False, _)) = False -- Imports are specified explicitly - import_all other = True -- Everything is imported - - -- mv_map groups together all the things imported and used - -- from a particular module in this package - -- We use a finite map because we want the domain - mv_map :: ModuleEnv [Name] - mv_map = foldNameSet add_mv emptyModuleEnv imp_home_names - add_mv name mv_map = extendModuleEnv_C add_item mv_map mod [name] - where - mod = nameModule name - add_item names _ = name:names - - -- In our usage list we record - -- a) Specifically: Detailed version info for imports from modules in this package - -- Gotten from iVSlurp plus import_all_mods - -- - -- b) Everything: Just the module version for imports from modules in other packages - -- Gotten from iVSlurp plus import_all_mods - -- - -- c) NothingAtAll: The name only of modules, Baz, in this package that are 'below' us, - -- but which we didn't need at all (this is needed only to decide whether - -- to open Baz.hi or Baz.hi-boot higher up the tree). - -- This happens when a module, Foo, that we explicitly imported has - -- 'import Baz' in its interface file, recording that Baz is below - -- Foo in the module dependency hierarchy. We want to propagate this info. - -- These modules are in a combination of HIT/PIT and iImpModInfo - -- - -- d) NothingAtAll: The name only of all orphan modules we know of (this is needed - -- so that anyone who imports us can find the orphan modules) - -- These modules are in a combination of HIT/PIT and iImpModInfo - - import_info0 = foldModuleEnv mk_imp_info [] pit - import_info1 = foldModuleEnv mk_imp_info import_info0 hit - import_info = [ (mod_name, orphans, is_boot, NothingAtAll) - | (mod_name, (orphans, is_boot)) <- fmToList (iImpModInfo ifaces) ] ++ - import_info1 - - mk_imp_info :: ModIface -> [ImportVersion Name] -> [ImportVersion Name] - mk_imp_info iface so_far - - | Just ns <- lookupModuleEnv mv_map mod -- Case (a) - = go_for_it (Specifically mod_vers maybe_export_vers - (mk_import_items ns) rules_vers) - - | mod `elemModuleSet` imp_pkg_mods -- Case (b) - = go_for_it (Everything mod_vers) - - | import_all_mod -- Case (a) and (b); the import-all part - = if is_home_pkg_mod then - go_for_it (Specifically mod_vers (Just export_vers) [] rules_vers) - else - go_for_it (Everything mod_vers) - - | is_home_pkg_mod || has_orphans -- Case (c) or (d) - = go_for_it NothingAtAll - - | otherwise = so_far - where - go_for_it exports = (mod_name, has_orphans, mi_boot iface, exports) : so_far - - mod = mi_module iface - mod_name = moduleName mod - is_home_pkg_mod = isModuleInThisPackage mod - version_info = mi_version iface - version_env = vers_decls version_info - mod_vers = vers_module version_info - rules_vers = vers_rules version_info - export_vers = vers_exports version_info - import_all_mod = mod_name `elem` import_all_mods - has_orphans = mi_orphan iface - - -- The sort is to put them into canonical order - mk_import_items ns = [(n,v) | n <- sortLt lt_occ ns, - let v = lookupNameEnv version_env n `orElse` - pprPanic "mk_whats_imported" (ppr n) - ] - where - lt_occ n1 n2 = nameOccName n1 < nameOccName n2 - - maybe_export_vers | import_all_mod = Just (vers_exports version_info) - | otherwise = Nothing - in - returnRn import_info -\end{code} - -%********************************************************* %* * \subsection{Slurping declarations} %* * @@ -209,149 +55,247 @@ mkImportInfo this_mod imports \begin{code} ------------------------------------------------------- +slurpImpDecls :: FreeVars -> TcRn m [RenamedHsDecl] slurpImpDecls source_fvs - = traceRn (text "slurpImp" <+> fsep (map ppr (nameSetToList source_fvs))) `thenRn_` + = traceRn (text "slurpImp" <+> fsep (map ppr (nameSetToList source_fvs))) `thenM_` - -- The current slurped-set records all local things - getSlurped `thenRn` \ source_binders -> - slurpSourceRefs source_binders source_fvs `thenRn` \ (decls, needed) -> + -- Slurp in things which might be 'gates' for instance + -- declarations, plus the instance declarations themselves + slurpSourceRefs source_fvs `thenM` \ (gate_decls, bndrs) -> -- Then get everything else - closeDecls decls needed + let + needed = foldr (plusFV . impDeclFVs) emptyFVs gate_decls + in + import_supporting_decls (gate_decls, bndrs) needed ------------------------------------------------------- -slurpSourceRefs :: NameSet -- Variables defined in source - -> FreeVars -- Variables referenced in source - -> RnMG ([RenamedHsDecl], - FreeVars) -- Un-satisfied needs --- The declaration (and hence home module) of each gate has --- already been loaded - -slurpSourceRefs source_binders source_fvs - = go_outer [] -- Accumulating decls - emptyFVs -- Unsatisfied needs - emptyFVs -- Accumulating gates +slurpSourceRefs :: FreeVars -- Variables referenced in source + -> TcRn m ([RenamedHsDecl], -- Needed declarations + NameSet) -- Names bound by those declarations +-- Slurp imported declarations needed directly by the source code; +-- and some of the ones they need. The goal is to find all the 'gates' +-- for instance declarations. + +slurpSourceRefs source_fvs + = go_outer [] emptyFVs -- Accumulating decls (nameSetToList source_fvs) -- Things whose defn hasn't been loaded yet where -- The outer loop repeatedly slurps the decls for the current gates -- and the instance decls -- The outer loop is needed because consider - - go_outer decls fvs all_gates [] - = returnRn (decls, fvs) - - go_outer decls fvs all_gates refs -- refs are not necessarily slurped yet - = traceRn (text "go_outer" <+> ppr refs) `thenRn_` - foldlRn go_inner (decls, fvs, emptyFVs) refs `thenRn` \ (decls1, fvs1, gates1) -> - getImportedInstDecls (all_gates `plusFV` gates1) `thenRn` \ inst_decls -> - rnIfaceInstDecls decls1 fvs1 gates1 inst_decls `thenRn` \ (decls2, fvs2, gates2) -> - go_outer decls2 fvs2 (all_gates `plusFV` gates2) - (nameSetToList (gates2 `minusNameSet` all_gates)) - -- Knock out the all_gates because even if we don't slurp any new - -- decls we can get some apparently-new gates from wired-in names - - go_inner (decls, fvs, gates) wanted_name - = importDecl wanted_name `thenRn` \ import_result -> + -- instance Foo a => Baz (Maybe a) where ... + -- It may be that Baz and Maybe are used in the source module, + -- but not Foo; so we need to chase Foo too. + -- + -- We also need to follow superclass refs. In particular, 'chasing Foo' must + -- include actually getting in Foo's class decl + -- class Wib a => Foo a where .. + -- so that its superclasses are discovered. The point is that Wib is a gate too. + -- We do this for tycons too, so that we look through type synonyms. + + go_outer decls bndrs [] = returnM (decls, bndrs) + + go_outer decls bndrs refs -- 'refs' are not necessarily slurped yet + = traceRn (text "go_outer" <+> ppr refs) `thenM_` + foldlM go_inner (decls, bndrs, emptyFVs) refs `thenM` \ (decls1, bndrs1, gates1) -> + getImportedInstDecls gates1 `thenM` \ (inst_decls, new_gates) -> + rnIfaceDecls rnInstDecl inst_decls `thenM` \ inst_decls' -> + go_outer (map InstD inst_decls' ++ decls1) + bndrs1 + (nameSetToList (new_gates `plusFV` plusFVs (map getInstDeclGates inst_decls'))) + -- NB: we go round again to fetch the decls for any gates of any decls + -- we have loaded. For example, if we mention + -- print :: Show a => a -> String + -- then we must load the decl for Show before stopping, to ensure + -- that instances from its home module are available + + go_inner (decls, bndrs, gates) wanted_name + = importDecl bndrs wanted_name `thenM` \ import_result -> case import_result of - AlreadySlurped -> returnRn (decls, fvs, gates) - InTypeEnv ty_thing -> returnRn (decls, fvs, gates `plusFV` getWiredInGates ty_thing) - - HereItIs decl -> rnIfaceTyClDecl decl `thenRn` \ (new_decl, fvs1) -> - returnRn (TyClD new_decl : decls, - fvs1 `plusFV` fvs, - gates `plusFV` getGates source_fvs new_decl) + AlreadySlurped -> returnM (decls, bndrs, gates) + + InTypeEnv ty_thing + -> returnM (decls, + bndrs `addOneFV` wanted_name, -- Avoid repeated calls to getWiredInGates + gates `plusFV` getWiredInGates ty_thing) + + HereItIs decl new_bndrs + -> rnIfaceDecl rnTyClDecl decl `thenM` \ new_decl -> + returnM (TyClD new_decl : decls, + bndrs `plusFV` new_bndrs, + gates `plusFV` getGates source_fvs new_decl) \end{code} - \begin{code} ------------------------------------------------------- --- closeDecls keeps going until the free-var set is empty -closeDecls decls needed - | not (isEmptyFVs needed) - = slurpDecls decls needed `thenRn` \ (decls1, needed1) -> - closeDecls decls1 needed1 - - | otherwise - = getImportedRules `thenRn` \ rule_decls -> +-- import_supporting_decls keeps going until the free-var set is empty +importSupportingDecls needed + = import_supporting_decls ([], emptyNameSet) needed + +import_supporting_decls + :: ([RenamedHsDecl], NameSet) -- Some imported decls, with their binders + -> FreeVars -- Remaining un-slurped names + -> TcRn m [RenamedHsDecl] +import_supporting_decls decls needed + = slurpIfaceDecls decls needed `thenM` \ (decls1, bndrs1) -> + getImportedRules bndrs1 `thenM` \ rule_decls -> case rule_decls of - [] -> returnRn decls -- No new rules, so we are done - other -> rnIfaceDecls rnIfaceRuleDecl rule_decls `thenRn` \ rule_decls' -> + [] -> returnM decls1 -- No new rules, so we are done + other -> rnIfaceDecls rnIfaceRuleDecl rule_decls `thenM` \ rule_decls' -> let - rule_fvs = plusFVs (map ruleDeclFVs rule_decls') + rule_fvs = plusFVs (map ruleDeclFVs rule_decls') + decls2 = decls1 ++ map RuleD rule_decls' in - traceRn (text "closeRules" <+> ppr rule_decls' $$ fsep (map ppr (nameSetToList rule_fvs))) `thenRn_` - closeDecls (map RuleD rule_decls' ++ decls) rule_fvs + traceRn (text "closeRules" <+> ppr rule_decls' $$ + fsep (map ppr (nameSetToList rule_fvs))) `thenM_` + import_supporting_decls (decls2, bndrs1) rule_fvs - ------------------------------------------------------- --- Augment decls with any decls needed by needed. --- Return also free vars of the new decls (only) -slurpDecls decls needed - = go decls emptyFVs (nameSetToList needed) +-- Augment decls with any decls needed by needed, +-- and so on transitively +slurpIfaceDecls :: ([RenamedHsDecl], NameSet) -- Already slurped + -> FreeVars -- Still needed + -> TcRn m ([RenamedHsDecl], NameSet) +slurpIfaceDecls (decls, bndrs) needed + = slurp decls bndrs (nameSetToList needed) where - go decls fvs [] = returnRn (decls, fvs) - go decls fvs (ref:refs) = slurpDecl decls fvs ref `thenRn` \ (decls1, fvs1) -> - go decls1 fvs1 refs + slurp decls bndrs [] = returnM (decls, bndrs) + slurp decls bndrs (n:ns) + = importDecl bndrs n `thenM` \ import_result -> + case import_result of + HereItIs decl new_bndrs -- Found a declaration... rename it + -> rnIfaceDecl rnTyClDecl decl `thenM` \ new_decl -> + slurp (TyClD new_decl : decls) + (bndrs `plusFV` new_bndrs) + (nameSetToList (tyClDeclFVs new_decl) ++ ns) + + + other -> -- No declaration... (wired in thing, or deferred, + -- or already slurped) + slurp decls (bndrs `addOneFV` n) ns ------------------------------------------------------- -slurpDecl decls fvs wanted_name - = importDecl wanted_name `thenRn` \ import_result -> - case import_result of - -- Found a declaration... rename it - HereItIs decl -> rnIfaceTyClDecl decl `thenRn` \ (new_decl, fvs1) -> - returnRn (TyClD new_decl:decls, fvs1 `plusFV` fvs) +rnIfaceDecls rn decls = mappM (rnIfaceDecl rn) decls +rnIfaceDecl rn (mod, decl) = initRn (InterfaceMode mod) (rn decl) +\end{code} - -- No declaration... (wired in thing, or deferred, or already slurped) - other -> returnRn (decls, fvs) +\begin{code} + -- Tiresomely, we must get the "main" name for the + -- thing, because that's what VSlurp contains, and what + -- is recorded in the usage information +get_main_name (AClass cl) = className cl +get_main_name (ADataCon dc) = tyConName (dataConTyCon dc) +get_main_name (ATyCon tc) + | Just clas <- tyConClass_maybe tc = get_main_name (AClass clas) + | otherwise = tyConName tc +get_main_name (AnId id) + = case globalIdDetails id of + DataConWorkId dc -> get_main_name (ATyCon (dataConTyCon dc)) + DataConWrapId dc -> get_main_name (ATyCon (dataConTyCon dc)) + RecordSelId lbl -> get_main_name (ATyCon (fieldLabelTyCon lbl)) + GenericOpId tc -> get_main_name (ATyCon tc) + ClassOpId cl -> className cl + other -> idName id + + +recordUsage :: Name -> TcRn m () +-- Record that the Name has been used, for +-- later generation of usage info in the interface file +recordUsage name = updUsages (upd_usg name) + +upd_usg name usages + | isHomeModule mod = addOneToNameSet usages name + | otherwise = usages + where + mod = nameModule name +\end{code} -------------------------------------------------------- -rnIfaceDecls rn decls = mapRn (rnIfaceDecl rn) decls -rnIfaceDecl rn (mod, decl) = initIfaceRnMS mod (rn decl) -rnIfaceInstDecls decls fvs gates inst_decls - = rnIfaceDecls rnInstDecl inst_decls `thenRn` \ inst_decls' -> - returnRn (map InstD inst_decls' ++ decls, - fvs `plusFV` plusFVs (map instDeclFVs inst_decls'), - gates `plusFV` plusFVs (map getInstDeclGates inst_decls')) +%********************************************************* +%* * +\subsection{Getting in a declaration} +%* * +%********************************************************* -rnIfaceTyClDecl (mod, decl) = initIfaceRnMS mod (rnTyClDecl decl) `thenRn` \ decl' -> - returnRn (decl', tyClDeclFVs decl') -\end{code} +\begin{code} +importDecl :: NameSet -> Name -> TcRn m ImportDeclResult +data ImportDeclResult + = AlreadySlurped + | InTypeEnv TyThing + | HereItIs (Module, RdrNameTyClDecl) NameSet + -- The NameSet is the bunch of names bound by this decl + +importDecl already_slurped name + = -- STEP 0: Check if it's from this module + -- Doing this catches a common case quickly + getModule `thenM` \ this_mod -> + if nameIsLocalOrFrom this_mod name then + -- Variables defined on the GHCi command line (e.g. let x = 3) + -- are Internal names (which don't have a Module) + returnM AlreadySlurped + else -\begin{code} -getSlurped - = getIfacesRn `thenRn` \ ifaces -> - returnRn (iSlurp ifaces) - -recordSlurp ifaces@(Ifaces { iDecls = (decls_map, n_slurped), - iSlurp = slurped_names, - iVSlurp = (imp_mods, imp_names) }) - avail - = ASSERT2( not (isLocalName (availName avail)), ppr avail ) - ifaces { iDecls = (decls_map', n_slurped+1), - iSlurp = new_slurped_names, - iVSlurp = new_vslurp } - where - decls_map' = foldl delFromNameEnv decls_map (availNames avail) - main_name = availName avail - mod = nameModule main_name - new_slurped_names = addAvailToNameSet slurped_names avail - new_vslurp | isModuleInThisPackage mod = (imp_mods, addOneToNameSet imp_names main_name) - | otherwise = (extendModuleSet imp_mods mod, imp_names) - -recordLocalSlurps local_avails - = getIfacesRn `thenRn` \ ifaces -> + -- STEP 1: Check if we've slurped it in while compiling this module + if name `elemNameSet` already_slurped then + returnM AlreadySlurped + else + + -- STEP 2: Check if it's already in the type environment + tcLookupGlobal_maybe name `thenM` \ maybe_thing -> + case maybe_thing of { + + Just ty_thing + | isWiredInName name + -> -- When we find a wired-in name we must load its home + -- module so that we find any instance decls lurking therein + loadHomeInterface wi_doc name `thenM_` + returnM (InTypeEnv ty_thing) + + | otherwise + -> -- We have slurp something that's already in the type environment, + -- that was not slurped in an earlier compilation. + -- Must still record it in the Usages info, because that's used to + -- generate usage information + + traceRn (text "not wired in" <+> ppr name) `thenM_` + recordUsage (get_main_name ty_thing) `thenM_` + returnM (InTypeEnv ty_thing) ; + + Nothing -> + + -- STEP 4: OK, we have to slurp it in from an interface file + -- First load the interface file + traceRn nd_doc `thenM_` + loadHomeInterface nd_doc name `thenM_` + + -- STEP 4: Get the declaration out + getEps `thenM` \ eps -> let - new_slurped_names = foldl addAvailToNameSet (iSlurp ifaces) local_avails + (decls_map, n_slurped) = eps_decls eps in - setIfacesRn (ifaces { iSlurp = new_slurped_names }) -\end{code} + case lookupNameEnv decls_map name of + Just (avail,_,decl) -> setEps eps' `thenM_` + recordUsage (availName avail) `thenM_` + returnM (HereItIs decl (mkFVs avail_names)) + where + avail_names = availNames avail + new_decls_map = foldl delFromNameEnv decls_map avail_names + eps' = eps { eps_decls = (new_decls_map, n_slurped+1) } + + Nothing -> addErr (getDeclErr name) `thenM_` + returnM AlreadySlurped + } + where + wi_doc = ptext SLIT("need home module for wired in thing") <+> ppr name + nd_doc = ptext SLIT("need decl for") <+> ppr name +\end{code} %********************************************************* @@ -376,7 +320,11 @@ Each has its set of 'gates': {C, T1, T2} in the above example. More precisely, the gates of a module are the types and classes that are mentioned in: - a) the source code + a) the source code [Note: in fact these don't seem + to be treated as gates, perhaps + because no imported instance decl + can mention them; mutter mutter + recursive modules.] b) the type of an Id that's mentioned in the source code [includes constructors and selectors] c) the RHS of a type synonym that is a gate @@ -385,18 +333,35 @@ that are mentioned in: We slurp in an instance decl from the gated instance pool iff - all its gates are either in the gates of the module, - or are a previously-loaded class. + all its gates are either in the gates of the module, + or the gates of a previously-loaded module The latter constraint is because there might have been an instance decl slurped in during an earlier compilation, like this: instance Foo a => Baz (Maybe a) where ... -In the module being compiled we might need (Baz (Maybe T)), where T -is defined in this module, and hence we need (Foo T). So @Foo@ becomes -a gate. But there's no way to 'see' that, so we simply treat all -previously-loaded classes as gates. +In the module being compiled we might need (Baz (Maybe T)), where T is +defined in this module, and hence we need the instance for (Foo T). +So @Foo@ becomes a gate. But there's no way to 'see' that. More +generally, types might be involved as well: + + instance Foo2 S a => Baz2 a where ... + +Now we must treat S as a gate too, as well as Foo2. So the solution +we adopt is: + + we simply treat the gates of all previously-loaded + modules as gates of this one + +So the gates are remembered across invocations of the renamer in the +PersistentRenamerState. This gloss mainly affects ghc --make and ghc +--interactive. + +(We used to use the persistent type environment for this purpose, +but it has too much. For a start, it contains all tuple types, +because they are in the wired-in type env!) + Consructors and class operations ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ @@ -421,51 +386,44 @@ vars of the source program, and extracts from the decl the gate names. \begin{code} getGates :: FreeVars -- Things mentioned in the source program + -- Used for the cunning "constructors and + -- class ops" story described 10 lines above. -> RenamedTyClDecl -> FreeVars getGates source_fvs decl = get_gates (\n -> n `elemNameSet` source_fvs) decl -get_gates is_used (IfaceSig _ ty _ _) - = extractHsTyNames ty +get_gates is_used (ForeignType {tcdName = tycon}) = unitNameSet tycon +get_gates is_used (IfaceSig {tcdType = ty}) = extractHsTyNames ty -get_gates is_used (ClassDecl ctxt cls tvs _ sigs _ _ _ ) - = (delListFromNameSet (foldr (plusFV . get) (extractHsCtxtTyNames ctxt) sigs) - (hsTyVarNames tvs) - `addOneToNameSet` cls) - `plusFV` maybe_double +get_gates is_used (ClassDecl { tcdCtxt = ctxt, tcdName = cls, tcdTyVars = tvs, tcdSigs = sigs}) + = (super_cls_and_sigs `addOneToNameSet` cls) `unionNameSets` + implicitClassGates cls where + super_cls_and_sigs = delListFromNameSet (foldr (plusFV . get) (extractHsCtxtTyNames ctxt) sigs) + (hsTyVarNames tvs) get (ClassOpSig n _ ty _) | is_used n = extractHsTyNames ty | otherwise = emptyFVs - -- If we load any numeric class that doesn't have - -- Int as an instance, add Double to the gates. - -- This takes account of the fact that Double might be needed for - -- defaulting, but we don't want to load Double (and all its baggage) - -- if the more exotic classes aren't used at all. - maybe_double | nameUnique cls `elem` fractionalClassKeys - = unitFV (getName doubleTyCon) - | otherwise - = emptyFVs - -get_gates is_used (TySynonym tycon tvs ty _) +get_gates is_used (TySynonym {tcdTyVars = tvs, tcdSynRhs = ty}) = delListFromNameSet (extractHsTyNames ty) (hsTyVarNames tvs) -- A type synonym type constructor isn't a "gate" for instance decls -get_gates is_used (TyData _ ctxt tycon tvs cons _ _ _ _ _) - = delListFromNameSet (foldr (plusFV . get) (extractHsCtxtTyNames ctxt) cons) +get_gates is_used (TyData {tcdCtxt = ctxt, tcdName = tycon, tcdTyVars = tvs, tcdCons = cons}) + = delListFromNameSet (foldr (plusFV . get) (extractHsCtxtTyNames ctxt) + (visibleDataCons cons)) (hsTyVarNames tvs) `addOneToNameSet` tycon where - get (ConDecl n _ tvs ctxt details _) + get (ConDecl n tvs ctxt details _) | is_used n -- If the constructor is method, get fvs from all its fields = delListFromNameSet (get_details details `plusFV` extractHsCtxtTyNames ctxt) (hsTyVarNames tvs) - get (ConDecl n _ tvs ctxt (RecCon fields) _) + get (ConDecl n tvs ctxt (RecCon fields) _) -- Even if the constructor isn't mentioned, the fields -- might be, as selectors. They can't mention existentially -- bound tyvars (typechecker checks for that) so no need for @@ -474,14 +432,30 @@ get_gates is_used (TyData _ ctxt tycon tvs cons _ _ _ _ _) get other_con = emptyFVs - get_details (VanillaCon tys) = plusFVs (map get_bang tys) + get_details (PrefixCon tys) = plusFVs (map get_bang tys) get_details (InfixCon t1 t2) = get_bang t1 `plusFV` get_bang t2 get_details (RecCon fields) = plusFVs [get_bang t | (_, t) <- fields] - get_field (fs,t) | any is_used fs = get_bang t - | otherwise = emptyFVs + get_field (f,t) | is_used f = get_bang t + | otherwise = emptyFVs get_bang bty = extractHsTyNames (getBangType bty) + +implicitClassGates :: Name -> FreeVars +implicitClassGates cls + -- If we load class Num, add Integer to the free gates + -- This takes account of the fact that Integer might be needed for + -- defaulting, but we don't want to load Integer (and all its baggage) + -- if there's no numeric stuff needed. + -- Similarly for class Fractional and Double + -- + -- NB: adding T to the gates will force T to be loaded + -- + -- NB: If we load (say) Floating, we'll end up loading Fractional too, + -- since Fractional is a superclass of Floating + | cls `hasKey` numClassKey = unitFV integerTyConName + | cls `hasKey` fractionalClassKey = unitFV doubleTyConName + | otherwise = emptyFVs \end{code} @getWiredInGates@ is just like @getGates@, but it sees a previously-loaded @@ -492,81 +466,96 @@ getWiredInGates :: TyThing -> FreeVars -- The TyThing is one that we already have in our type environment, either -- a) because the TyCon or Id is wired in, or -- b) from a previous compile +-- -- Either way, we might have instance decls in the (persistent) collection -- of parsed-but-not-slurped instance decls that should be slurped in. -- This might be the first module that mentions both the type and the class -- for that instance decl, even though both the type and the class were -- mentioned in other modules, and hence are in the type environment -getWiredInGates (AnId the_id) = namesOfType (idType the_id) -getWiredInGates (AClass cl) = emptyFVs -- The superclasses must also be previously - -- loaded, and hence are automatically gates +getWiredInGates (AClass cl) + = unitFV (getName cl) `plusFV` mkFVs super_classes + where + super_classes = classNamesOfTheta (classSCTheta cl) + +getWiredInGates (AnId the_id) = tyClsNamesOfType (idType the_id) +getWiredInGates (ADataCon dc) = tyClsNamesOfType (idType (dataConWrapId dc)) + -- Should include classes in the 'stupid context' of the data con? getWiredInGates (ATyCon tc) - | isSynTyCon tc = delListFromNameSet (namesOfType ty) (map getName tyvars) + | isSynTyCon tc = tyClsNamesOfType ty | otherwise = unitFV (getName tc) where - (tyvars,ty) = getSynTyConDefn tc + (_,ty) = getSynTyConDefn tc getInstDeclGates (InstDecl inst_ty _ _ _ _) = extractHsTyNames inst_ty \end{code} \begin{code} -getImportedInstDecls :: NameSet -> RnMG [(Module,RdrNameInstDecl)] +getImportedInstDecls :: NameSet -> TcRn m ([(Module,RdrNameInstDecl)], NameSet) + -- Returns the gates that are new since last time getImportedInstDecls gates = -- First, load any orphan-instance modules that aren't aready loaded -- Orphan-instance modules are recorded in the module dependecnies - getIfacesRn `thenRn` \ ifaces -> + getImports `thenM` \ imports -> + getEps `thenM` \ eps -> let - orphan_mods = - [mod | (mod, (True, _)) <- fmToList (iImpModInfo ifaces)] + old_gates = eps_inst_gates eps + new_gates = gates `minusNameSet` old_gates + all_gates = new_gates `unionNameSets` old_gates + orphan_mods = imp_orphs imports in - loadOrphanModules orphan_mods `thenRn_` + loadOrphanModules orphan_mods `thenM_` -- Now we're ready to grab the instance declarations -- Find the un-gated ones and return them, - -- removing them from the bag kept in Ifaces - getIfacesRn `thenRn` \ ifaces -> - getTypeEnvRn `thenRn` \ lookup -> + -- removing them from the bag kept in EPS + -- Don't foget to get the EPS a second time... + -- loadOrphanModules may have side-effected it! + getEps `thenM` \ eps -> let - (decls, new_insts) = selectGated gates lookup (iInsts ifaces) + available n = n `elemNameSet` all_gates + (decls, new_insts) = selectGated available (eps_insts eps) in - setIfacesRn (ifaces { iInsts = new_insts }) `thenRn_` + setEps (eps { eps_insts = new_insts, + eps_inst_gates = all_gates }) `thenM_` traceRn (sep [text "getImportedInstDecls:", - nest 4 (fsep (map ppr gate_list)), + nest 4 (fsep (map ppr (nameSetToList gates))), + nest 4 (fsep (map ppr (nameSetToList all_gates))), + nest 4 (fsep (map ppr (nameSetToList new_gates))), text "Slurped" <+> int (length decls) <+> text "instance declarations", - nest 4 (vcat (map ppr_brief_inst_decl decls))]) `thenRn_` - returnRn decls - where - gate_list = nameSetToList gates + nest 4 (vcat (map ppr_brief_inst_decl decls))]) `thenM_` + returnM (decls, new_gates) ppr_brief_inst_decl (mod, InstDecl inst_ty _ _ _ _) = case inst_ty of HsForAllTy _ _ tau -> ppr tau other -> ppr inst_ty -getImportedRules :: RnMG [(Module,RdrNameRuleDecl)] -getImportedRules - | opt_IgnoreIfacePragmas = returnRn [] +getImportedRules :: NameSet -- Slurped already + -> TcRn m [(Module,RdrNameRuleDecl)] +getImportedRules slurped + | opt_IgnoreIfacePragmas = returnM [] | otherwise - = getIfacesRn `thenRn` \ ifaces -> - getTypeEnvRn `thenRn` \ lookup -> - let - gates = iSlurp ifaces -- Anything at all that's been slurped - rules = iRules ifaces - (decls, new_rules) = selectGated gates lookup rules + = getEps `thenM` \ eps -> + getInGlobalScope `thenM` \ in_type_env -> + let -- Slurp rules for anything that is slurped, + -- either now, or previously + available n = n `elemNameSet` slurped || in_type_env n + (decls, new_rules) = selectGated available (eps_rules eps) in if null decls then - returnRn [] + returnM [] else - setIfacesRn (ifaces { iRules = new_rules }) `thenRn_` + setEps (eps { eps_rules = new_rules }) `thenM_` traceRn (sep [text "getImportedRules:", - text "Slurped" <+> int (length decls) <+> text "rules"]) `thenRn_` - returnRn decls + text "Slurped" <+> int (length decls) <+> text "rules"]) `thenM_` + returnM decls -selectGated gates lookup (decl_bag, n_slurped) - -- Select only those decls whose gates are *all* in 'gates' - -- or are a class in 'lookup' +selectGated :: (Name->Bool) -> GatedDecls d + -> ([(Module,d)], GatedDecls d) +selectGated available (decl_bag, n_slurped) + -- Select only those decls whose gates are *all* available #ifdef DEBUG | opt_NoPruneDecls -- Just to try the effect of not gating at all = let @@ -579,79 +568,9 @@ selectGated gates lookup (decl_bag, n_slurped) = case foldrBag select ([], emptyBag) decl_bag of (decls, new_bag) -> (decls, (new_bag, n_slurped + length decls)) where - available n = n `elemNameSet` gates - || case lookup n of { Just (AClass c) -> True; other -> False } - - select (reqd, decl) (yes, no) - | all available reqd = (decl:yes, no) - | otherwise = (yes, (reqd,decl) `consBag` no) -\end{code} - - -%********************************************************* -%* * -\subsection{Getting in a declaration} -%* * -%********************************************************* - -\begin{code} -importDecl :: Name -> RnMG ImportDeclResult - -data ImportDeclResult - = AlreadySlurped - | InTypeEnv TyThing - | HereItIs (Module, RdrNameTyClDecl) - -importDecl name - = -- STEP 1: Check if it was loaded before beginning this module - if isLocalName name then - traceRn (text "Already (local)" <+> ppr name) `thenRn_` - returnRn AlreadySlurped - else - - -- STEP 2: Check if we've slurped it in while compiling this module - getIfacesRn `thenRn` \ ifaces -> - if name `elemNameSet` iSlurp ifaces then - returnRn AlreadySlurped - else - - -- STEP 3: Check if it's already in the type environment - getTypeEnvRn `thenRn` \ lookup -> - case lookup name of { - Just ty_thing | name `elemNameEnv` wiredInThingEnv - -> -- When we find a wired-in name we must load its home - -- module so that we find any instance decls lurking therein - loadHomeInterface wi_doc name `thenRn_` - returnRn (InTypeEnv ty_thing) - - | otherwise - -> returnRn (InTypeEnv ty_thing) ; - - Nothing -> - - -- STEP 4: OK, we have to slurp it in from an interface file - -- First load the interface file - traceRn nd_doc `thenRn_` - loadHomeInterface nd_doc name `thenRn_` - getIfacesRn `thenRn` \ ifaces -> - - -- STEP 5: Get the declaration out - let - (decls_map, _) = iDecls ifaces - in - case lookupNameEnv decls_map name of - Just (avail,_,decl) - -> setIfacesRn (recordSlurp ifaces avail) `thenRn_` - returnRn (HereItIs decl) - - Nothing - -> addErrRn (getDeclErr name) `thenRn_` - returnRn AlreadySlurped - } - where - wi_doc = ptext SLIT("need home module for wired in thing") <+> ppr name - nd_doc = ptext SLIT("need decl for") <+> ppr name - + select (gate_fn, decl) (yes, no) + | gate_fn available = (decl:yes, no) + | otherwise = (yes, (gate_fn,decl) `consBag` no) \end{code} @@ -671,118 +590,112 @@ type RecompileRequired = Bool upToDate = False -- Recompile not required outOfDate = True -- Recompile required -recompileRequired :: FilePath -- Only needed for debug msgs - -> Bool -- Source unchanged - -> ModIface -- Old interface - -> RnMG RecompileRequired -recompileRequired iface_path source_unchanged iface - = traceHiDiffsRn (text "Considering whether compilation is required for" <+> text iface_path <> colon) `thenRn_` - - -- CHECK WHETHER THE SOURCE HAS CHANGED - if not source_unchanged then - traceHiDiffsRn (nest 4 (text "Source file changed or recompilation check turned off")) `thenRn_` - returnRn outOfDate - else +checkVersions :: Bool -- True <=> source unchanged + -> ModIface -- Old interface + -> TcRn m RecompileRequired +checkVersions source_unchanged iface + | not source_unchanged + = returnM outOfDate + | otherwise + = traceHiDiffs (text "Considering whether compilation is required for" <+> + ppr (mi_module iface) <> colon) `thenM_` -- Source code unchanged and no errors yet... carry on - checkList [checkModUsage u | u <- mi_usages iface] + -- First put the dependent-module info in the envt, just temporarily, + -- so that when we look for interfaces we look for the right one (.hi or .hi-boot) + -- It's just temporary because either the usage check will succeed + -- (in which case we are done with this module) or it'll fail (in which + -- case we'll compile the module from scratch anyhow). + updGblEnv (\ gbl -> gbl { tcg_imports = mod_deps }) ( + checkList [checkModUsage u | u <- mi_usages iface] + ) + + where + -- This is a bit of a hack really + mod_deps = emptyImportAvails { imp_dep_mods = mkModDeps (dep_mods (mi_deps iface)) } -checkList :: [RnMG RecompileRequired] -> RnMG RecompileRequired -checkList [] = returnRn upToDate -checkList (check:checks) = check `thenRn` \ recompile -> +checkList :: [TcRn m RecompileRequired] -> TcRn m RecompileRequired +checkList [] = returnM upToDate +checkList (check:checks) = check `thenM` \ recompile -> if recompile then - returnRn outOfDate + returnM outOfDate else checkList checks \end{code} \begin{code} -checkModUsage :: ImportVersion Name -> RnMG RecompileRequired +checkModUsage :: Usage Name -> TcRn m RecompileRequired -- Given the usage information extracted from the old -- M.hi file for the module being compiled, figure out -- whether M needs to be recompiled. -checkModUsage (mod_name, _, _, NothingAtAll) - -- If CurrentModule.hi contains - -- import Foo :: ; - -- then that simply records that Foo lies below CurrentModule in the - -- hierarchy, but CurrentModule doesn't depend in any way on Foo. - -- In this case we don't even want to open Foo's interface. - = up_to_date (ptext SLIT("Nothing used from:") <+> ppr mod_name) - -checkModUsage (mod_name, _, is_boot, whats_imported) +checkModUsage (Usage { usg_name = mod_name, usg_mod = old_mod_vers, + usg_rules = old_rule_vers, + usg_exports = maybe_old_export_vers, + usg_entities = old_decl_vers }) = -- Load the imported interface is possible - -- We use tryLoadInterface, because failure is not an error - -- (might just be that the old .hi file for this module is out of date) - -- We use ImportByUser/ImportByUserSource as the 'from' flag, - -- a) because we need to know whether to load the .hi-boot file - -- b) because loadInterface things matters are amiss if we - -- ImportBySystem an interface it knows nothing about let doc_str = sep [ptext SLIT("need version info for"), ppr mod_name] - from | is_boot = ImportByUserSource - | otherwise = ImportByUser in - tryLoadInterface doc_str mod_name from `thenRn` \ (iface, maybe_err) -> + traceHiDiffs (text "Checking usages for module" <+> ppr mod_name) `thenM_` + + tryM (loadInterface doc_str mod_name ImportBySystem) `thenM` \ mb_iface -> - case maybe_err of { - Just err -> out_of_date (sep [ptext SLIT("Can't find version number for module"), - ppr mod_name]) ; + case mb_iface of { + Left exn -> (out_of_date (sep [ptext SLIT("Can't find version number for module"), + ppr mod_name])); -- Couldn't find or parse a module mentioned in the -- old interface file. Don't complain -- it might just be that -- the current module doesn't need that import and it's been deleted - Nothing -> + Right iface -> let - new_vers = mi_version iface - new_decl_vers = vers_decls new_vers + new_vers = mi_version iface + new_mod_vers = vers_module new_vers + new_decl_vers = vers_decls new_vers + new_export_vers = vers_exports new_vers + new_rule_vers = vers_rules new_vers in - case whats_imported of { -- NothingAtAll dealt with earlier - - Everything old_mod_vers -> checkModuleVersion old_mod_vers new_vers `thenRn` \ recompile -> - if recompile then - out_of_date (ptext SLIT("...and I needed the whole module")) - else - returnRn upToDate ; - - Specifically old_mod_vers maybe_old_export_vers old_decl_vers old_rule_vers -> - -- CHECK MODULE - checkModuleVersion old_mod_vers new_vers `thenRn` \ recompile -> + checkModuleVersion old_mod_vers new_mod_vers `thenM` \ recompile -> if not recompile then - returnRn upToDate + returnM upToDate else -- CHECK EXPORT LIST - if checkExportList maybe_old_export_vers new_vers then - out_of_date (ptext SLIT("Export list changed")) + if checkExportList maybe_old_export_vers new_export_vers then + out_of_date_vers (ptext SLIT(" Export list changed")) + (fromJust maybe_old_export_vers) + new_export_vers else -- CHECK RULES - if old_rule_vers /= vers_rules new_vers then - out_of_date (ptext SLIT("Rules changed")) + if old_rule_vers /= new_rule_vers then + out_of_date_vers (ptext SLIT(" Rules changed")) + old_rule_vers new_rule_vers else -- CHECK ITEMS ONE BY ONE - checkList [checkEntityUsage new_decl_vers u | u <- old_decl_vers] `thenRn` \ recompile -> + checkList [checkEntityUsage new_decl_vers u | u <- old_decl_vers] `thenM` \ recompile -> if recompile then - returnRn outOfDate -- This one failed, so just bail out now + returnM outOfDate -- This one failed, so just bail out now else - up_to_date (ptext SLIT("...but the bits I use haven't.")) + up_to_date (ptext SLIT(" Great! The bits I use are up to date")) - }} + } ------------------------ -checkModuleVersion old_mod_vers new_vers - | vers_module new_vers == old_mod_vers +checkModuleVersion old_mod_vers new_mod_vers + | new_mod_vers == old_mod_vers = up_to_date (ptext SLIT("Module version unchanged")) | otherwise - = out_of_date (ptext SLIT("Module version has changed")) + = out_of_date_vers (ptext SLIT(" Module version has changed")) + old_mod_vers new_mod_vers ------------------------ checkExportList Nothing new_vers = upToDate -checkExportList (Just v) new_vers = v /= vers_exports new_vers +checkExportList (Just v) new_vers = v /= new_vers ------------------------ checkEntityUsage new_vers (name,old_vers) @@ -792,11 +705,15 @@ checkEntityUsage new_vers (name,old_vers) out_of_date (sep [ptext SLIT("No longer exported:"), ppr name]) Just new_vers -- It's there, but is it up to date? - | new_vers == old_vers -> returnRn upToDate - | otherwise -> out_of_date (sep [ptext SLIT("Out of date:"), ppr name]) - -up_to_date msg = traceHiDiffsRn msg `thenRn_` returnRn upToDate -out_of_date msg = traceHiDiffsRn msg `thenRn_` returnRn outOfDate + | new_vers == old_vers -> traceHiDiffs (text " Up to date" <+> ppr name <+> parens (ppr new_vers)) `thenM_` + returnM upToDate + | otherwise -> out_of_date_vers (ptext SLIT(" Out of date:") <+> ppr name) + old_vers new_vers + +up_to_date msg = traceHiDiffs msg `thenM_` returnM upToDate +out_of_date msg = traceHiDiffs msg `thenM_` returnM outOfDate +out_of_date_vers msg old_vers new_vers + = out_of_date (hsep [msg, ppr old_vers, ptext SLIT("->"), ppr new_vers]) \end{code}