%
-% (c) The GRASP/AQUA Project, Glasgow University, 1992-1996
+% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
%
\section[RnIfaces]{Cacheing and Renaming of Interfaces}
\begin{code}
-#include "HsVersions.h"
-
-module RnIfaces (
+module RnIfaces
+ (
getInterfaceExports,
- getImportedInstDecls,
- getSpecialInstModules,
- getDecl, getWiredInDecl,
- getImportVersions,
-
- checkUpToDate,
+ recordLocalSlurps,
+ mkImportInfo,
- getDeclBinders,
- mkSearchPath
- ) where
+ slurpImpDecls, closeDecls,
-IMP_Ubiq()
+ RecompileRequired, outOfDate, upToDate, recompileRequired
+ )
+where
+#include "HsVersions.h"
-import HsSyn ( HsDecl(..), TyDecl(..), ClassDecl(..), HsTyVar, Bind, HsExpr, Sig(..),
- HsBinds(..), MonoBinds, DefaultDecl, ConDecl(..), HsType, BangType, IfaceSig(..),
- FixityDecl(..), Fixity, Fake, InPat, InstDecl(..), SYN_IE(Version), HsIdInfo
+import CmdLineOpts ( DynFlags, opt_NoPruneDecls, opt_NoPruneTyDecls, opt_IgnoreIfacePragmas )
+import HscTypes
+import HsSyn ( HsDecl(..), Sig(..), TyClDecl(..), ConDecl(..), ConDetails(..),
+ InstDecl(..), HsType(..), hsTyVarNames, getBangType
)
-import HsPragmas ( noGenPragmas )
-import RdrHsSyn ( SYN_IE(RdrNameHsDecl), SYN_IE(RdrNameInstDecl),
- RdrName, rdrNameOcc
+import HsImpExp ( ImportDecl(..) )
+import RdrHsSyn ( RdrNameHsDecl, RdrNameTyClDecl, RdrNameInstDecl )
+import RnHsSyn ( RenamedHsDecl, extractHsTyNames, extractHsCtxtTyNames, tyClDeclFVs )
+import RnHiFiles ( tryLoadInterface, loadHomeInterface, loadInterface,
+ loadOrphanModules
)
-import RnEnv ( newGlobalName, lookupRn, addImplicitOccsRn, availNames )
-import RnSource ( rnHsType )
+import RnSource ( rnTyClDecl, rnDecl )
+import RnEnv
import RnMonad
-import ParseIface ( parseIface )
-
-import ErrUtils ( SYN_IE(Error), SYN_IE(Warning) )
-import FiniteMap ( FiniteMap, emptyFM, unitFM, lookupFM, addToFM, addListToFM, fmToList )
-import Name ( Name {-instance NamedThing-}, Provenance, OccName(..),
- modAndOcc, occNameString, moduleString, pprModule,
- NameSet(..), emptyNameSet, unionNameSets, nameSetToList,
- minusNameSet, mkNameSet,
- isWiredInName, maybeWiredInTyConName, maybeWiredInIdName
- )
-import Id ( GenId, Id(..), idType, dataConTyCon, isDataCon )
-import TyCon ( TyCon, tyConDataCons, isSynTyCon, getSynTyConDefn )
+import Id ( idType )
import Type ( namesOfType )
-import TyVar ( GenTyVar )
-import SrcLoc ( mkIfaceSrcLoc )
-import PrelMods ( gHC__ )
+import TyCon ( isSynTyCon, getSynTyConDefn )
+import Name ( Name {-instance NamedThing-}, nameOccName,
+ nameModule, isLocallyDefined, nameUnique,
+ NamedThing(..),
+ elemNameEnv
+ )
+import Module ( Module, ModuleEnv,
+ moduleName, isModuleInThisPackage,
+ ModuleName, WhereFrom(..),
+ emptyModuleEnv, lookupModuleEnvByName,
+ extendModuleEnv_C, lookupWithDefaultModuleEnv
+ )
+import NameSet
+import PrelInfo ( wiredInThingEnv, fractionalClassKeys )
+import TysWiredIn ( doubleTyCon )
+import Maybes ( orElse )
+import FiniteMap
+import Outputable
import Bag
-import Maybes ( MaybeErr(..), expectJust, maybeToBool )
-import ListSetOps ( unionLists )
-import Pretty
-import PprStyle ( PprStyle(..) )
-import Util ( pprPanic )
+
+import List ( nub )
\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
+ = getHomeIfaceTableRn `thenRn` \ hit ->
+ case lookupModuleEnvByName hit mod_name of {
+ Just mi -> returnRn (mi_module mi, mi_exports mi) ;
+ Nothing ->
+
+ loadInterface doc_str mod_name from `thenRn` \ ifaces ->
+ case lookupModuleEnvByName (iPIT ifaces) mod_name of
+ Just mi -> returnRn (mi_module mi, mi_exports mi) ;
+ -- loadInterface always puts something in the map
+ -- even if it's a fake
+ Nothing -> pprPanic "getInterfaceExports" (ppr mod_name)
+ }
+ where
+ doc_str = sep [ppr mod_name, ptext SLIT("is directly imported")]
+\end{code}
+
%*********************************************************
%* *
-\subsection{Loading a new interface file}
+\subsection{Instance declarations are handled specially}
%* *
%*********************************************************
\begin{code}
-loadInterface :: Pretty -> Module -> RnMG Ifaces
-loadInterface doc_str load_mod
- = getIfacesRn `thenRn` \ ifaces ->
+getImportedInstDecls :: NameSet -> RnMG [(Module,RdrNameHsDecl)]
+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 ->
let
- Ifaces this_mod mod_vers_map export_env_map vers_map decls_map inst_map inst_mods = ifaces
+ orphan_mods =
+ [mod | (mod, (True, _, False)) <- fmToList (iImpModInfo ifaces)]
in
- -- CHECK WHETHER WE HAVE IT ALREADY
- if maybeToBool (lookupFM export_env_map load_mod)
- then
- returnRn ifaces -- Already in the cache; don't re-read it
- else
+ loadOrphanModules orphan_mods `thenRn_`
- -- READ THE MODULE IN
- findAndReadIface doc_str load_mod `thenRn` \ read_result ->
- case read_result of {
- -- Check for not found
- Nothing -> -- Not found, so add an empty export env to the Ifaces map
- -- so that we don't look again
- let
- new_export_env_map = addToFM export_env_map load_mod ([],[])
- new_ifaces = Ifaces this_mod mod_vers_map
- new_export_env_map
- vers_map decls_map inst_map inst_mods
- in
- setIfacesRn new_ifaces `thenRn_`
- failWithRn new_ifaces (noIfaceErr load_mod) ;
-
- -- Found and parsed!
- Just (ParsedIface _ mod_vers usages exports rd_inst_mods fixs decls insts) ->
-
- -- LOAD IT INTO Ifaces
- mapRn loadExport exports `thenRn` \ avails_s ->
- foldlRn (loadDecl load_mod) (decls_map,vers_map) decls `thenRn` \ (new_decls_map, new_vers_map) ->
- foldlRn (loadInstDecl load_mod) inst_map insts `thenRn` \ new_insts_map ->
+ -- 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 ->
let
- export_env = (concat avails_s, fixs)
-
- -- Exclude this module from the "special-inst" modules
- new_inst_mods = inst_mods `unionLists` (filter (/= this_mod) rd_inst_mods)
-
- new_ifaces = Ifaces this_mod
- (addToFM mod_vers_map load_mod mod_vers)
- (addToFM export_env_map load_mod export_env)
- new_vers_map
- new_decls_map
- new_insts_map
- new_inst_mods
+ (decls, new_insts) = selectGated gates (iInsts ifaces)
in
- setIfacesRn new_ifaces `thenRn_`
- returnRn new_ifaces
- }
+ setIfacesRn (ifaces { iInsts = new_insts }) `thenRn_`
-loadExport :: ExportItem -> RnMG [AvailInfo]
-loadExport (mod, entities)
- = mapRn load_entity entities
+ traceRn (sep [text "getImportedInstDecls:",
+ nest 4 (fsep (map ppr gate_list)),
+ text "Slurped" <+> int (length decls) <+> text "instance declarations",
+ nest 4 (vcat (map ppr_brief_inst_decl decls))]) `thenRn_`
+ returnRn decls
where
- new_name occ = newGlobalName mod occ
-
- load_entity (occ, occs)
- = new_name occ `thenRn` \ name ->
- mapRn new_name occs `thenRn` \ names ->
- returnRn (Avail name names)
-
-loadVersion :: Module -> VersionMap -> (OccName,Version) -> RnMG VersionMap
-loadVersion mod vers_map (occ, version)
- = newGlobalName mod occ `thenRn` \ name ->
- returnRn (addToFM vers_map name version)
-
-
-loadDecl :: Module -> (DeclsMap, VersionMap)
- -> (Version, RdrNameHsDecl)
- -> RnMG (DeclsMap, VersionMap)
-loadDecl mod (decls_map, vers_map) (version, decl)
- = getDeclBinders new_implicit_name decl `thenRn` \ avail@(Avail name _) ->
- returnRn (addListToFM decls_map
- [(name,(avail,decl)) | name <- availNames avail],
- addToFM vers_map name version
- )
+ gate_list = nameSetToList gates
+
+ppr_brief_inst_decl (mod, InstD (InstDecl inst_ty _ _ _ _))
+ = case inst_ty of
+ HsForAllTy _ _ tau -> ppr tau
+ other -> ppr inst_ty
+
+getImportedRules :: RnMG [(Module,RdrNameHsDecl)]
+getImportedRules
+ | opt_IgnoreIfacePragmas = returnRn []
+ | otherwise
+ = getIfacesRn `thenRn` \ ifaces ->
+ let
+ gates = iSlurp ifaces -- Anything at all that's been slurped
+ rules = iRules ifaces
+ (decls, new_rules) = selectGated gates rules
+ in
+ if null decls then
+ returnRn []
+ else
+ setIfacesRn (ifaces { iRules = new_rules }) `thenRn_`
+ traceRn (sep [text "getImportedRules:",
+ text "Slurped" <+> int (length decls) <+> text "rules"]) `thenRn_`
+ returnRn decls
+
+selectGated gates decl_bag
+ -- Select only those decls whose gates are *all* in 'gates'
+#ifdef DEBUG
+ | opt_NoPruneDecls -- Just to try the effect of not gating at all
+ = (foldrBag (\ (_,d) ds -> d:ds) [] decl_bag, emptyBag) -- Grab them all
+
+ | otherwise
+#endif
+ = foldrBag select ([], emptyBag) decl_bag
where
- new_implicit_name rdr_name loc = newGlobalName mod (rdrNameOcc rdr_name)
+ select (reqd, decl) (yes, no)
+ | isEmptyNameSet (reqd `minusNameSet` gates) = (decl:yes, no)
+ | otherwise = (yes, (reqd,decl) `consBag` no)
+\end{code}
+
+
+%*********************************************************
+%* *
+\subsection{Keeping track of what we've slurped, and version numbers}
+%* *
+%*********************************************************
+
+getImportVersions 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. It records:
+
+\begin{itemize}
+\item (a) anything reachable from its body code
+\item (b) any module exported with a @module Foo@
+\item (c) anything reachable from an exported item
+\end{itemize}
+
+Why (b)? Because if @Foo@ changes then this module's export list
+will change, so we must recompile this module at least as far as
+making a new interface file --- but in practice that means complete
+recompilation.
+
+Why (c)? Consider this:
+\begin{verbatim}
+ module A( f, g ) where | module B( f ) where
+ import B( f ) | f = h 3
+ g = ... | h = ...
+\end{verbatim}
+
+Here, @B.f@ isn't used in A. Should we nevertheless record @B.f@ in
+@A@'s usages? Our idea is that we aren't going to touch A.hi if it is
+*identical* to what it was before. If anything about @B.f@ changes
+than anyone who imports @A@ should be recompiled in case they use
+@B.f@ (they'll get an early exit if they don't). So, if anything
+about @B.f@ changes we'd better make sure that something in A.hi
+changes, and the convenient way to do that is to record the version
+number @B.f@ in A.hi in the usage list. If B.f changes that'll force a
+complete recompiation of A, which is overkill but it's the only way to
+write a new, slightly different, A.hi.
+
+But the example is tricker. Even if @B.f@ doesn't change at all,
+@B.h@ may do so, and this change may not be reflected in @f@'s version
+number. But with -O, a module that imports A must be recompiled if
+@B.h@ changes! So A must record a dependency on @B.h@. So we treat
+the occurrence of @B.f@ in the export list *just as if* it were in the
+code of A, and thereby haul in all the stuff reachable from it.
+
+[NB: If B was compiled with -O, but A isn't, we should really *still*
+haul in all the unfoldings for B, in case the module that imports A *is*
+compiled with -O. I think this is the case.]
+
+Even if B is used at all we get a usage line for B
+ import B <n> :: ... ;
+in A.hi, to record the fact that A does import B. 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.
-loadInstDecl :: Module -> Bag IfaceInst -> RdrNameInstDecl -> RnMG (Bag IfaceInst)
-loadInstDecl mod_name insts decl@(InstDecl inst_ty binds uprags dfun_name src_loc)
- = initRnMS emptyRnEnv mod_name InterfaceMode $
+\begin{code}
+mkImportInfo :: ModuleName -- Name of this module
+ -> [ImportDecl n] -- The import decls
+ -> RnMG [ImportVersion Name]
- -- Find out what type constructors and classes are mentioned in the
- -- instance declaration. We have to be a bit clever.
+mkImportInfo this_mod imports
+ = getIfacesRn `thenRn` \ ifaces ->
+ getHomeIfaceTableRn `thenRn` \ hit ->
+ let
+ import_all_mods :: [ModuleName]
+ -- Modules where we imported all the names
+ -- (apart from hiding some, perhaps)
+ import_all_mods = nub [ m | ImportDecl m _ _ _ imp_list _ <- imports,
+ import_all imp_list ]
+
+ import_all (Just (False, _)) = False -- Imports are specified explicitly
+ import_all other = True -- Everything is imported
+
+ mod_map = iImpModInfo ifaces
+ imp_names = iVSlurp ifaces
+ pit = iPIT ifaces
+
+ -- mv_map groups together all the things imported from a particular module.
+ mv_map :: ModuleEnv [Name]
+ mv_map = foldr add_mv emptyModuleEnv imp_names
+
+ add_mv name mv_map = addItem mv_map (nameModule name) name
+
+ -- Build the result list by adding info for each module.
+ -- For (a) a library module, we don't record it at all unless it contains orphans
+ -- (We must never lose track of orphans.)
+ --
+ -- (b) a source-imported module, don't record the dependency at all
+ --
+ -- (b) may seem a bit strange. The idea is that the usages in a .hi file records
+ -- *all* the module's dependencies other than the loop-breakers. We use
+ -- this info in findAndReadInterface to decide whether to look for a .hi file or
+ -- a .hi-boot file.
--
- -- We want to rename the type so that we can find what
- -- (free) type constructors are inside it. But we must *not* thereby
- -- put new occurrences into the global pool because otherwise we'll force
- -- them all to be loaded. We kill two birds with ones stone by renaming
- -- with a fresh occurrence pool.
- findOccurrencesRn (rnHsType inst_ty) `thenRn` \ ty_names ->
-
- returnRn ((ty_names, mod_name, decl) `consBag` insts)
+ -- This means we won't track version changes, or orphans, from .hi-boot files.
+ -- The former is potentially rather bad news. It could be fixed by recording
+ -- whether something is a boot file along with the usage info for it, but
+ -- I can't be bothered just now.
+
+ mk_imp_info mod_name (has_orphans, is_boot, opened) so_far
+ | mod_name == this_mod -- Check if M appears in the set of modules 'below' M
+ -- This seems like a convenient place to check
+ = WARN( not is_boot, ptext SLIT("Wierd:") <+> ppr this_mod <+>
+ ptext SLIT("imports itself (perhaps indirectly)") )
+ so_far
+
+ | not opened -- We didn't even open the interface
+ = -- 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
+ -- information. The Nothing says that we didn't even open the interface
+ -- file but we must still propagate the dependency info.
+ -- The module in question must be a local module (in the same package)
+ go_for_it NothingAtAll
+
+
+ | is_lib_module && not has_orphans
+ = so_far
+
+ | is_lib_module -- Record the module version only
+ = go_for_it (Everything module_vers)
+
+ | otherwise
+ = go_for_it whats_imported
+
+ where
+ go_for_it exports = (mod_name, has_orphans, is_boot, exports) : so_far
+ mod_iface = lookupTableByModName hit pit mod_name `orElse` panic "mkImportInfo"
+ mod = mi_module mod_iface
+ is_lib_module = not (isModuleInThisPackage mod)
+ version_info = mi_version mod_iface
+ version_env = vers_decls version_info
+ module_vers = vers_module version_info
+
+ whats_imported = Specifically module_vers
+ export_vers import_items
+ (vers_rules version_info)
+
+ import_items = [(n,v) | n <- lookupWithDefaultModuleEnv mv_map [] mod,
+ let v = lookupNameEnv version_env n `orElse`
+ pprPanic "mk_whats_imported" (ppr n)
+ ]
+ export_vers | moduleName mod `elem` import_all_mods
+ = Just (vers_exports version_info)
+ | otherwise
+ = Nothing
+
+ import_info = foldFM mk_imp_info [] mod_map
+ in
+ traceRn (text "Modules in Ifaces: " <+> fsep (map ppr (keysFM mod_map))) `thenRn_`
+ returnRn import_info
+
+
+addItem :: ModuleEnv [a] -> Module -> a -> ModuleEnv [a]
+addItem fm mod x = extendModuleEnv_C add_item fm mod [x]
+ where
+ add_item xs _ = x:xs
\end{code}
+%*********************************************************
+%* *
+\subsection{Slurping declarations}
+%* *
+%*********************************************************
+
+\begin{code}
+-------------------------------------------------------
+slurpImpDecls source_fvs
+ = traceRn (text "slurpImp" <+> fsep (map ppr (nameSetToList source_fvs))) `thenRn_`
+
+ -- The current slurped-set records all local things
+ getSlurped `thenRn` \ source_binders ->
+ slurpSourceRefs source_binders source_fvs `thenRn` \ (decls, needed) ->
+
+ -- Then get everything else
+ closeDecls decls needed `thenRn` \ decls1 ->
+
+ -- Finally, get any deferred data type decls
+ slurpDeferredDecls decls1 `thenRn` \ final_decls ->
+
+ returnRn final_decls
+
+
+-------------------------------------------------------
+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
+ (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
+ -- 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 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 ->
+ rnInstDecls 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 ->
+ case import_result of
+ AlreadySlurped -> returnRn (decls, fvs, gates)
+ WiredIn -> returnRn (decls, fvs, gates `plusFV` getWiredInGates wanted_name)
+ Deferred -> returnRn (decls, fvs, gates `addOneFV` wanted_name) -- It's a type constructor
+
+ HereItIs decl -> rnIfaceTyClDecl decl `thenRn` \ (new_decl, fvs1) ->
+ returnRn (TyClD new_decl : decls,
+ fvs1 `plusFV` fvs,
+ gates `plusFV` getGates source_fvs new_decl)
+
+rnInstDecls decls fvs gates []
+ = returnRn (decls, fvs, gates)
+rnInstDecls decls fvs gates (d:ds)
+ = rnIfaceDecl d `thenRn` \ (new_decl, fvs1) ->
+ rnInstDecls (new_decl:decls)
+ (fvs1 `plusFV` fvs)
+ (gates `plusFV` getInstDeclGates new_decl)
+ ds
+\end{code}
-%********************************************************
-%* *
-\subsection{Loading usage information}
-%* *
-%********************************************************
\begin{code}
-checkUpToDate :: Module -> RnMG Bool -- True <=> no need to recompile
-checkUpToDate mod_name
- = findAndReadIface doc_str mod_name `thenRn` \ read_result ->
- case read_result of
- Nothing -> -- Old interface file not found, so we'd better bale out
- traceRn (ppSep [ppStr "Didnt find old iface", pprModule PprDebug mod_name]) `thenRn_`
- returnRn False
-
- Just (ParsedIface _ _ usages _ _ _ _ _)
- -> -- Found it, so now check it
- checkModUsage usages
+-------------------------------------------------------
+-- 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 ->
+ case rule_decls of
+ [] -> returnRn decls -- No new rules, so we are done
+ other -> rnIfaceDecls decls emptyFVs rule_decls `thenRn` \ (decls1, needed1) ->
+ closeDecls decls1 needed1
+
+
+-------------------------------------------------------
+-- 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)
where
- -- Only look in current directory, with suffix .hi
- doc_str = ppSep [ppStr "Need usage info from", pprModule PprDebug mod_name]
+ go decls fvs [] = returnRn (decls, fvs)
+ go decls fvs (ref:refs) = slurpDecl decls fvs ref `thenRn` \ (decls1, fvs1) ->
+ go decls1 fvs1 refs
+
+-------------------------------------------------------
+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)
+
+ -- No declaration... (wired in thing, or deferred, or already slurped)
+ other -> returnRn (decls, fvs)
+
+
+-------------------------------------------------------
+rnIfaceDecls :: [RenamedHsDecl] -> FreeVars
+ -> [(Module, RdrNameHsDecl)]
+ -> RnM d ([RenamedHsDecl], FreeVars)
+rnIfaceDecls decls fvs [] = returnRn (decls, fvs)
+rnIfaceDecls decls fvs (d:ds) = rnIfaceDecl d `thenRn` \ (new_decl, fvs1) ->
+ rnIfaceDecls (new_decl:decls) (fvs1 `plusFV` fvs) ds
+
+rnIfaceDecl (mod, decl) = initIfaceRnMS mod (rnDecl decl)
+rnIfaceTyClDecl (mod, decl) = initIfaceRnMS mod (rnTyClDecl decl) `thenRn` \ decl' ->
+ returnRn (decl', tyClDeclFVs decl')
+\end{code}
-checkModUsage [] = returnRn True -- Yes! Everything is up to date!
+\begin{code}
+getSlurped
+ = getIfacesRn `thenRn` \ ifaces ->
+ returnRn (iSlurp ifaces)
+
+recordSlurp ifaces@(Ifaces { iSlurp = slurped_names, iVSlurp = imp_names })
+ avail
+ = let
+ new_slurped_names = addAvailToNameSet slurped_names avail
+ new_imp_names = availName avail : imp_names
+ in
+ ifaces { iSlurp = new_slurped_names, iVSlurp = new_imp_names }
-checkModUsage ((mod, old_mod_vers, old_local_vers) : rest)
- = loadInterface doc_str mod `thenRn` \ ifaces ->
+recordLocalSlurps local_avails
+ = getIfacesRn `thenRn` \ ifaces ->
let
- Ifaces _ mod_vers_map _ new_vers_map _ _ _ = ifaces
- maybe_new_mod_vers = lookupFM mod_vers_map mod
- Just new_mod_vers = maybe_new_mod_vers
+ new_slurped_names = foldl addAvailToNameSet (iSlurp ifaces) local_avails
in
- -- If we can't find a version number for the old module then
- -- bale out saying things aren't up to date
- if not (maybeToBool maybe_new_mod_vers) then
- returnRn False
- else
-
- -- If the module version hasn't changed, just move on
- if new_mod_vers == old_mod_vers then
- traceRn (ppSep [ppStr "Module version unchanged:", pprModule PprDebug mod]) `thenRn_`
- checkModUsage rest
- else
- traceRn (ppSep [ppStr "Module version has changed:", pprModule PprDebug mod]) `thenRn_`
+ setIfacesRn (ifaces { iSlurp = new_slurped_names })
+\end{code}
- -- New module version, so check entities inside
- checkEntityUsage mod new_vers_map old_local_vers `thenRn` \ up_to_date ->
- if up_to_date then
- traceRn (ppStr "...but the bits I use havn't.") `thenRn_`
- checkModUsage rest -- This one's ok, so check the rest
- else
- returnRn False -- This one failed, so just bail out now
- where
- doc_str = ppSep [ppStr "need version info for", pprModule PprDebug mod]
-checkEntityUsage mod new_vers_map []
- = returnRn True -- Yes! All up to date!
+%*********************************************************
+%* *
+\subsection{Deferred declarations}
+%* *
+%*********************************************************
-checkEntityUsage mod new_vers_map ((occ_name,old_vers) : rest)
- = newGlobalName mod occ_name `thenRn` \ name ->
- case lookupFM new_vers_map name of
+The idea of deferred declarations is this. Suppose we have a function
+ f :: T -> Int
+ data T = T1 A | T2 B
+ data A = A1 X | A2 Y
+ data B = B1 P | B2 Q
+Then we don't want to load T and all its constructors, and all
+the types those constructors refer to, and all the types *those*
+constructors refer to, and so on. That might mean loading many more
+interface files than is really necessary. So we 'defer' loading T.
+
+But f might be strict, and the calling convention for evaluating
+values of type T depends on how many constructors T has, so
+we do need to load T, but not the full details of the type T.
+So we load the full decl for T, but only skeleton decls for A and B:
+ f :: T -> Int
+ data T = {- 2 constructors -}
+
+Whether all this is worth it is moot.
- Nothing -> -- We used it before, but it ain't there now
- traceRn (ppSep [ppStr "...and this no longer exported:", ppr PprDebug name]) `thenRn_`
- returnRn False
-
- Just new_vers -> -- It's there, but is it up to date?
- if new_vers == old_vers then
- -- Up to date, so check the rest
- checkEntityUsage mod new_vers_map rest
- else
- traceRn (ppSep [ppStr "...and this is out of date:", ppr PprDebug name]) `thenRn_`
- returnRn False -- Out of date, so bale out
+\begin{code}
+slurpDeferredDecls :: [RenamedHsDecl] -> RnMG [RenamedHsDecl]
+slurpDeferredDecls decls = returnRn decls
+
+{- OMIT FOR NOW
+slurpDeferredDecls :: [RenamedHsDecl] -> RnMG [RenamedHsDecl]
+slurpDeferredDecls decls
+ = getDeferredDecls `thenRn` \ def_decls ->
+ rnIfaceDecls decls emptyFVs (map stripDecl def_decls) `thenRn` \ (decls1, fvs) ->
+ ASSERT( isEmptyFVs fvs )
+ returnRn decls1
+
+stripDecl (mod, TyClD (TyData dt _ tc tvs _ nconstrs _ loc name1 name2))
+ = (mod, TyClD (TyData dt [] tc tvs [] nconstrs Nothing loc
+ name1 name2))
+ -- Nuke the context and constructors
+ -- But retain the *number* of constructors!
+ -- Also the tvs will have kinds on them.
+-}
\end{code}
%*********************************************************
-%* *
-\subsection{Getting in a declaration}
-%* *
+%* *
+\subsection{Extracting the `gates'}
+%* *
%*********************************************************
-\begin{code}
-getDecl :: Name -> RnMG (AvailInfo, RdrNameHsDecl)
-getDecl name
- = traceRn doc_str `thenRn_`
- loadInterface doc_str mod `thenRn` \ (Ifaces _ _ _ _ decls_map _ _) ->
- case lookupFM decls_map name of
+When we import a declaration like
+\begin{verbatim}
+ data T = T1 Wibble | T2 Wobble
+\end{verbatim}
+we don't want to treat @Wibble@ and @Wobble@ as gates
+{\em unless} @T1@, @T2@ respectively are mentioned by the user program.
+If only @T@ is mentioned
+we want only @T@ to be a gate;
+that way we don't suck in useless instance
+decls for (say) @Eq Wibble@, when they can't possibly be useful.
- Just avail_w_decl -> returnRn avail_w_decl
+@getGates@ takes a newly imported (and renamed) decl, and the free
+vars of the source program, and extracts from the decl the gate names.
- Nothing -> -- Can happen legitimately for "Optional" occurrences
- returnRn (NotAvailable, ValD EmptyBinds)
+\begin{code}
+getGates source_fvs (IfaceSig _ ty _ _)
+ = extractHsTyNames ty
+
+getGates source_fvs (ClassDecl ctxt cls tvs _ sigs _ _ _ )
+ = (delListFromNameSet (foldr (plusFV . get) (extractHsCtxtTyNames ctxt) sigs)
+ (hsTyVarNames tvs)
+ `addOneToNameSet` cls)
+ `plusFV` maybe_double
where
- (mod,_) = modAndOcc name
- doc_str = ppSep [ppStr "Need decl for", ppr PprDebug name]
-\end{code}
+ get (ClassOpSig n _ ty _)
+ | n `elemNameSet` source_fvs = 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
+
+getGates source_fvs (TySynonym tycon tvs ty _)
+ = delListFromNameSet (extractHsTyNames ty)
+ (hsTyVarNames tvs)
+ -- A type synonym type constructor isn't a "gate" for instance decls
+
+getGates source_fvs (TyData _ ctxt tycon tvs cons _ _ _ _ _)
+ = delListFromNameSet (foldr (plusFV . get) (extractHsCtxtTyNames ctxt) cons)
+ (hsTyVarNames tvs)
+ `addOneToNameSet` tycon
+ where
+ get (ConDecl n _ tvs ctxt details _)
+ | n `elemNameSet` source_fvs
+ -- 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) _)
+ -- 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
+ -- the deleteListFromNameSet part
+ = foldr (plusFV . get_field) emptyFVs fields
+
+ get other_con = emptyFVs
-@getWiredInDecl@ maps a wired-in @Name@ to what it makes available.
-It behaves exactly as if the wired in decl were actually in an interface file.
-Specifically,
- * if the wired-in name is a data type constructor or a data constructor,
- it brings in the type constructor and all the data constructors; and
- marks as "occurrences" any free vars of the data con.
+ get_details (VanillaCon 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]
- * similarly for synonum type constructor
+ get_field (fs,t) | any (`elemNameSet` source_fvs) fs = get_bang t
+ | otherwise = emptyFVs
- * if the wired-in name is another wired-in Id, it marks as "occurrences"
- the free vars of the Id's type.
+ get_bang bty = extractHsTyNames (getBangType bty)
+\end{code}
- * it loads the interface file for the wired-in thing for the
- sole purpose of making sure that its instance declarations are available
+@getWiredInGates@ is just like @getGates@, but it sees a wired-in @Name@
+rather than a declaration.
-All this is necessary so that we know all types that are "in play", so
-that we know just what instances to bring into scope.
-
\begin{code}
-getWiredInDecl :: Name -> RnMG AvailInfo
-getWiredInDecl name
- = -- Force in the home module in case it has instance decls for
- -- the thing we are interested in
- (if not is_tycon || mod == gHC__ then
- returnRn () -- Mini hack 1: no point for non-tycons; and if we
- -- do this we find PrelNum trying to import PackedString,
- -- because PrelBase's .hi file mentions PackedString.unpackString
- -- But PackedString.hi isn't built by that point!
- --
- -- Mini hack 2; GHC is guaranteed not to have
- -- instance decls, so it's a waste of time
- -- to read it
- else
- loadInterface doc_str mod `thenRn_`
- returnRn ()
- ) `thenRn_`
-
- if is_tycon then
- get_wired_tycon the_tycon
- else -- Must be a wired-in-Id
- if (isDataCon the_id) then -- ... a wired-in data constructor
- get_wired_tycon (dataConTyCon the_id)
- else -- ... a wired-in non data-constructor
- get_wired_id the_id
- where
- doc_str = ppSep [ppStr "Need home module for wired in thing", ppr PprDebug name]
- (mod,_) = modAndOcc name
- maybe_wired_in_tycon = maybeWiredInTyConName name
- is_tycon = maybeToBool maybe_wired_in_tycon
- maybe_wired_in_id = maybeWiredInIdName name
- Just the_tycon = maybe_wired_in_tycon
- Just the_id = maybe_wired_in_id
-
-get_wired_id id
- = addImplicitOccsRn (nameSetToList id_mentioned) `thenRn_`
- returnRn (Avail (getName id) [])
- where
- id_mentioned = namesOfType (idType id)
+getWiredInGates :: Name -> FreeVars
+getWiredInGates name -- No classes are wired in
+ = case lookupNameEnv wiredInThingEnv name of
+ Just (AnId the_id) -> getWiredInGates_s (namesOfType (idType the_id))
+
+ Just (ATyCon tc)
+ | isSynTyCon tc
+ -> getWiredInGates_s (delListFromNameSet (namesOfType ty) (map getName tyvars))
+ where
+ (tyvars,ty) = getSynTyConDefn tc
-get_wired_tycon tycon
- | isSynTyCon tycon
- = addImplicitOccsRn (nameSetToList mentioned) `thenRn_`
- returnRn (Avail (getName tycon) [])
- where
- (tyvars,ty) = getSynTyConDefn tycon
- mentioned = namesOfType ty `minusNameSet` mkNameSet (map getName tyvars)
+ other -> unitFV name
-get_wired_tycon tycon
- | otherwise -- data or newtype
- = addImplicitOccsRn (nameSetToList mentioned) `thenRn_`
- returnRn (Avail (getName tycon) (map getName data_cons))
- where
- data_cons = tyConDataCons tycon
- mentioned = foldr (unionNameSets . namesOfType . idType) emptyNameSet data_cons
+getWiredInGates_s names = foldr (plusFV . getWiredInGates) emptyFVs (nameSetToList names)
+\end{code}
+
+\begin{code}
+getInstDeclGates (InstD (InstDecl inst_ty _ _ _ _)) = extractHsTyNames inst_ty
+getInstDeclGates other = emptyFVs
\end{code}
%*********************************************************
%* *
-\subsection{Getting other stuff}
+\subsection{Getting in a declaration}
%* *
%*********************************************************
\begin{code}
-getInterfaceExports :: Module -> RnMG (Avails, [(OccName,Fixity)])
-getInterfaceExports mod
- = loadInterface doc_str mod `thenRn` \ (Ifaces _ _ export_envs _ _ _ _) ->
- case lookupFM export_envs mod of
- Nothing -> -- Not there; it must be that the interface file wasn't found;
- -- the error will have been reported already.
- -- (Actually loadInterface should put the empty export env in there
- -- anyway, but this does no harm.)
- returnRn ([],[])
-
- Just stuff -> returnRn stuff
- where
- doc_str = ppSep [pprModule PprDebug mod, ppStr "is directly imported"]
+importDecl :: Name -> RnMG ImportDeclResult
+
+data ImportDeclResult
+ = AlreadySlurped
+ | WiredIn
+ | Deferred
+ | HereItIs (Module, RdrNameTyClDecl)
+
+importDecl name
+ = -- Check if it was loaded before beginning this module
+ checkAlreadyAvailable name `thenRn` \ done ->
+ if done then
+ returnRn AlreadySlurped
+ else
+ -- Check if we slurped it in while compiling this module
+ getIfacesRn `thenRn` \ ifaces ->
+ if name `elemNameSet` iSlurp ifaces then
+ returnRn AlreadySlurped
+ else
+
+ -- Don't slurp in decls from this module's own interface file
+ -- (Indeed, this shouldn't happen.)
+ if isLocallyDefined name then
+ addWarnRn (importDeclWarn name) `thenRn_`
+ returnRn AlreadySlurped
+ else
-getImportedInstDecls :: RnMG [IfaceInst]
-getImportedInstDecls
- = -- First load any special-instance modules that aren't aready loaded
- getSpecialInstModules `thenRn` \ inst_mods ->
- mapRn load_it inst_mods `thenRn_`
+ -- When we find a wired-in name we must load its home
+ -- module so that we find any instance decls lurking therein
+ if name `elemNameEnv` wiredInThingEnv then
+ loadHomeInterface doc name `thenRn_`
+ returnRn WiredIn
- -- Now we're ready to grab the instance declarations
- getIfacesRn `thenRn` \ ifaces ->
- let
- Ifaces _ _ _ _ _ insts _ = ifaces
- in
- returnRn (bagToList insts)
+ else getNonWiredInDecl name
where
- load_it mod = loadInterface (doc_str mod) mod
- doc_str mod = ppSep [pprModule PprDebug mod, ppStr "is a special-instance module"]
+ doc = ptext SLIT("need home module for wired in thing") <+> ppr name
+
+getNonWiredInDecl :: Name -> RnMG ImportDeclResult
+getNonWiredInDecl needed_name
+ = traceRn doc_str `thenRn_`
+ loadHomeInterface doc_str needed_name `thenRn` \ ifaces ->
+ case lookupNameEnv (iDecls ifaces) needed_name of
+
+{- OMIT DEFERRED STUFF FOR NOW, TILL GHCI WORKS
+ Just (version, avail, is_tycon_name, decl@(_, TyClD (TyData DataType _ _ _ _ ncons _ _ _ _)))
+ -- This case deals with deferred import of algebraic data types
+
+ | not opt_NoPruneTyDecls
+
+ && (opt_IgnoreIfacePragmas || ncons > 1)
+ -- We only defer if imported interface pragmas are ingored
+ -- or if it's not a product type.
+ -- Sole reason: The wrapper for a strict function may need to look
+ -- inside its arg, and hence need to see its arg type's constructors.
+
+ && not (getUnique tycon_name `elem` cCallishTyKeys)
+ -- Never defer ccall types; we have to unbox them,
+ -- and importing them does no harm
+
+
+ -> -- OK, so we're importing a deferrable data type
+ if needed_name == tycon_name
+ -- The needed_name is the TyCon of a data type decl
+ -- Record that it's slurped, put it in the deferred set
+ -- and don't return a declaration at all
+ setIfacesRn (recordSlurp (ifaces {iDeferred = iDeferred ifaces
+ `addOneToNameSet` tycon_name})
+ version (AvailTC needed_name [needed_name])) `thenRn_`
+ returnRn Deferred
+
+ else
+ -- The needed name is a constructor of a data type decl,
+ -- getting a constructor, so remove the TyCon from the deferred set
+ -- (if it's there) and return the full declaration
+ setIfacesRn (recordSlurp (ifaces {iDeferred = iDeferred ifaces
+ `delFromNameSet` tycon_name})
+ version avail) `thenRn_`
+ returnRn (HereItIs decl)
+ where
+ tycon_name = availName avail
+-}
-getSpecialInstModules :: RnMG [Module]
-getSpecialInstModules
- = getIfacesRn `thenRn` \ ifaces ->
- let
- Ifaces _ _ _ _ _ _ inst_mods = ifaces
- in
- returnRn inst_mods
-\end{code}
+ Just (avail,_,decl)
+ -> setIfacesRn (recordSlurp ifaces avail) `thenRn_`
+ returnRn (HereItIs decl)
-\begin{code}
-getImportVersions :: [AvailInfo] -- Imported avails
- -> RnMG (VersionInfo Name) -- Version info for these names
+ Nothing
+ -> addErrRn (getDeclErr needed_name) `thenRn_`
+ returnRn AlreadySlurped
+ where
+ doc_str = ptext SLIT("need decl for") <+> ppr needed_name
-getImportVersions imported_avails
- = getIfacesRn `thenRn` \ ifaces ->
+{- OMIT FOR NOW
+getDeferredDecls :: RnMG [(Module, RdrNameHsDecl)]
+getDeferredDecls
+ = getIfacesRn `thenRn` \ ifaces ->
let
- Ifaces _ mod_versions_map _ version_map _ _ _ = ifaces
-
- -- import_versions is harder: we have to group together all the things imported
- -- from a particular module. We do this with yet another finite map
-
- mv_map :: FiniteMap Module [LocalVersion Name]
- mv_map = foldl add_mv emptyFM imported_avails
- add_mv mv_map (Avail name _)
- | isWiredInName name = mv_map -- Don't record versions for wired-in names
- | otherwise = case lookupFM mv_map mod of
- Just versions -> addToFM mv_map mod ((name,version):versions)
- Nothing -> addToFM mv_map mod [(name,version)]
- where
- (mod,_) = modAndOcc name
- version = case lookupFM version_map name of
- Just v -> v
- Nothing -> pprPanic "getVersionInfo:" (ppr PprDebug name)
-
- import_versions = [ (mod, expectJust "import_versions" (lookupFM mod_versions_map mod), local_versions)
- | (mod, local_versions) <- fmToList mv_map
- ]
-
- -- Question: should we filter the builtins out of import_versions?
+ decls_map = iDecls ifaces
+ deferred_names = nameSetToList (iDeferred ifaces)
+ get_abstract_decl n = case lookupNameEnv decls_map n of
+ Just (_, _, _, decl) -> decl
in
- returnRn import_versions
+ traceRn (sep [text "getDeferredDecls", nest 4 (fsep (map ppr deferred_names))]) `thenRn_`
+ returnRn (map get_abstract_decl deferred_names)
+-}
\end{code}
-%*********************************************************
+@getWiredInDecl@ maps a wired-in @Name@ to what it makes available.
+It behaves exactly as if the wired in decl were actually in an interface file.
+Specifically,
+\begin{itemize}
+\item if the wired-in name is a data type constructor or a data constructor,
+ it brings in the type constructor and all the data constructors; and
+ marks as ``occurrences'' any free vars of the data con.
+
+\item similarly for synonum type constructor
+
+\item if the wired-in name is another wired-in Id, it marks as ``occurrences''
+ the free vars of the Id's type.
+
+\item it loads the interface file for the wired-in thing for the
+ sole purpose of making sure that its instance declarations are available
+\end{itemize}
+All this is necessary so that we know all types that are ``in play'', so
+that we know just what instances to bring into scope.
+
+
+%********************************************************
%* *
-\subsection{Getting binders out of a declaration}
+\subsection{Checking usage information}
%* *
-%*********************************************************
+%********************************************************
-@getDeclBinders@ returns the names for a @RdrNameHsDecl@.
-It's used for both source code (from @availsFromDecl@) and interface files
-(from @loadDecl@).
+@recompileRequired@ is called from the HscMain. It checks whether
+a recompilation is required. It needs access to the persistent state,
+finder, etc, because it may have to load lots of interface files to
+check their versions.
-It doesn't deal with source-code specific things: ValD, DefD. They
-are handled by the sourc-code specific stuff in RnNames.
+\begin{code}
+type RecompileRequired = Bool
+upToDate = False -- Recompile not required
+outOfDate = True -- Recompile required
+
+recompileRequired :: Module
+ -> Bool -- Source unchanged
+ -> Maybe ModIface -- Old interface, if any
+ -> RnMG RecompileRequired
+recompileRequired mod source_unchanged maybe_iface
+ = traceRn (text "Considering whether compilation is required for" <+> ppr mod <> colon) `thenRn_`
+
+ -- CHECK WHETHER THE SOURCE HAS CHANGED
+ if not source_unchanged then
+ traceRn (nest 4 (text "Source file changed or recompilation check turned off")) `thenRn_`
+ returnRn outOfDate
+ else
+ -- CHECK WHETHER WE HAVE AN OLD IFACE
+ case maybe_iface of
+ Nothing -> traceRn (nest 4 (ptext SLIT("No old interface file"))) `thenRn_`
+ returnRn outOfDate ;
+
+ Just iface -> -- Source code unchanged and no errors yet... carry on
+ checkList [checkModUsage u | u <- mi_usages iface]
+
+checkList :: [RnMG RecompileRequired] -> RnMG RecompileRequired
+checkList [] = returnRn upToDate
+checkList (check:checks) = check `thenRn` \ recompile ->
+ if recompile then
+ returnRn outOfDate
+ else
+ checkList checks
+\end{code}
+
\begin{code}
-getDeclBinders :: (RdrName -> SrcLoc -> RnMG Name) -- New-name function
- -> RdrNameHsDecl
- -> RnMG AvailInfo
-
-getDeclBinders new_name (TyD (TyData _ tycon _ condecls _ _ src_loc))
- = new_name tycon src_loc `thenRn` \ tycon_name ->
- getConFieldNames new_name condecls `thenRn` \ sub_names ->
- returnRn (Avail tycon_name sub_names)
-
-getDeclBinders new_name (TyD (TyNew _ tycon _ (NewConDecl con _ con_loc) _ _ src_loc))
- = new_name tycon src_loc `thenRn` \ tycon_name ->
- new_name con src_loc `thenRn` \ con_name ->
- returnRn (Avail tycon_name [con_name])
-
-getDeclBinders new_name (TyD (TySynonym tycon _ _ src_loc))
- = new_name tycon src_loc `thenRn` \ tycon_name ->
- returnRn (Avail tycon_name [])
-
-getDeclBinders new_name (ClD (ClassDecl _ cname _ sigs _ _ src_loc))
- = new_name cname src_loc `thenRn` \ class_name ->
- mapRn (getClassOpNames new_name) sigs `thenRn` \ sub_names ->
- returnRn (Avail class_name sub_names)
-
-getDeclBinders new_name (SigD (IfaceSig var ty prags src_loc))
- = new_name var src_loc `thenRn` \ var_name ->
- returnRn (Avail var_name [])
-
-getDeclBinders new_name (DefD _) = returnRn NotAvailable
-getDeclBinders new_name (InstD _) = returnRn NotAvailable
-
-----------------
-getConFieldNames new_name (ConDecl con _ src_loc : rest)
- = new_name con src_loc `thenRn` \ n ->
- getConFieldNames new_name rest `thenRn` \ ns ->
- returnRn (n:ns)
-
-getConFieldNames new_name (NewConDecl con _ src_loc : rest)
- = new_name con src_loc `thenRn` \ n ->
- getConFieldNames new_name rest `thenRn` \ ns ->
- returnRn (n:ns)
-
-getConFieldNames new_name (ConOpDecl _ con _ src_loc : rest)
- = new_name con src_loc `thenRn` \ n ->
- getConFieldNames new_name rest `thenRn` \ ns ->
- returnRn (n:ns)
-
-getConFieldNames new_name (RecConDecl con fielddecls src_loc : rest)
- = mapRn (\n -> new_name n src_loc) (con:fields) `thenRn` \ cfs ->
- getConFieldNames new_name rest `thenRn` \ ns ->
- returnRn (cfs ++ ns)
- where
- fields = concat (map fst fielddecls)
+checkModUsage :: ImportVersion Name -> RnMG 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, _, _, whats_imported)
+ = tryLoadInterface doc_str mod_name ImportBySystem `thenRn` \ (ifaces, maybe_err) ->
+ case maybe_err of {
+ Just err -> 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 ->
+
+ getHomeIfaceTableRn `thenRn` \ hit ->
+ let
+ mod_details = lookupTableByModName hit (iPIT ifaces) mod_name
+ `orElse` panic "checkModUsage"
+ new_vers = mi_version mod_details
+ new_decl_vers = vers_decls new_vers
+ in
+ case whats_imported of { -- NothingAtAll dealt with earlier
-getConFieldNames new_name [] = returnRn []
+ 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 ;
-getClassOpNames new_name (ClassOpSig op _ _ src_loc) = new_name op src_loc
-\end{code}
+ Specifically old_mod_vers maybe_old_export_vers old_decl_vers old_rule_vers ->
+ -- CHECK MODULE
+ checkModuleVersion old_mod_vers new_vers `thenRn` \ recompile ->
+ if not recompile then
+ returnRn upToDate
+ else
+
+ -- CHECK EXPORT LIST
+ if checkExportList maybe_old_export_vers new_vers then
+ out_of_date (ptext SLIT("Export list changed"))
+ else
-%*********************************************************
-%* *
-\subsection{Reading an interface file}
-%* *
-%*********************************************************
+ -- CHECK RULES
+ if old_rule_vers /= vers_rules new_vers then
+ out_of_date (ptext SLIT("Rules changed"))
+ else
-\begin{code}
-findAndReadIface :: Pretty -> Module -> RnMG (Maybe ParsedIface)
- -- Nothing <=> file not found, or unreadable, or illegible
- -- Just x <=> successfully found and parsed
-findAndReadIface doc_str mod
- = traceRn trace_msg `thenRn_`
- getSearchPathRn `thenRn` \ dirs ->
- try dirs dirs
+ -- CHECK ITEMS ONE BY ONE
+ checkList [checkEntityUsage new_decl_vers u | u <- old_decl_vers] `thenRn` \ recompile ->
+ if recompile then
+ returnRn outOfDate -- This one failed, so just bail out now
+ else
+ up_to_date (ptext SLIT("...but the bits I use haven't."))
+
+ }}
where
- trace_msg = ppHang (ppBesides [ppStr "Reading interface for ",
- pprModule PprDebug mod, ppSemi])
- 4 (ppBesides [ppStr "reason: ", doc_str])
-
- try all_dirs [] = traceRn (ppStr "...failed") `thenRn_`
- returnRn Nothing
-
- try all_dirs (dir:dirs)
- = readIface file_path `thenRn` \ read_result ->
- case read_result of
- Nothing -> try all_dirs dirs
- Just iface -> traceRn (ppStr "...done") `thenRn_`
- returnRn (Just iface)
- where
- file_path = dir ++ "/" ++ moduleString mod ++ ".hi"
-\end{code}
+ doc_str = sep [ptext SLIT("need version info for"), ppr mod_name]
-@readIface@ trys just one file.
+------------------------
+checkModuleVersion old_mod_vers new_vers
+ | vers_module new_vers == old_mod_vers
+ = up_to_date (ptext SLIT("Module version unchanged"))
-\begin{code}
-readIface :: String -> RnMG (Maybe ParsedIface)
- -- Nothing <=> file not found, or unreadable, or illegible
- -- Just x <=> successfully found and parsed
-readIface file_path
- = ioToRnMG (readFile file_path) `thenRn` \ read_result ->
- case read_result of
- Right contents -> case parseIface contents of
- Failed err -> failWithRn Nothing err
- Succeeded iface -> returnRn (Just iface)
+ | otherwise
+ = out_of_date (ptext SLIT("Module version has changed"))
- Left (NoSuchThing _) -> returnRn Nothing
+------------------------
+checkExportList Nothing new_vers = upToDate
+checkExportList (Just v) new_vers = v /= vers_exports new_vers
- Left err -> failWithRn Nothing
- (cannaeReadFile file_path err)
+------------------------
+checkEntityUsage new_vers (name,old_vers)
+ = case lookupNameEnv new_vers name of
-\end{code}
-
-mkSearchPath takes a string consisting of a colon-separated list of directories, and turns it into
-a list of directories. For example:
+ Nothing -> -- We used it before, but it ain't there now
+ out_of_date (sep [ptext SLIT("No longer exported:"), ppr name])
- mkSearchPath "foo:.:baz" = ["foo", ".", "baz"]
+ 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])
-\begin{code}
-mkSearchPath :: Maybe String -> SearchPath
-mkSearchPath Nothing = ["."]
-mkSearchPath (Just s)
- = go s
- where
- go "" = []
- go s = first : go (drop 1 rest)
- where
- (first,rest) = span (/= ':') s
+up_to_date msg = traceRn msg `thenRn_` returnRn upToDate
+out_of_date msg = traceRn msg `thenRn_` returnRn outOfDate
\end{code}
+
%*********************************************************
-%* *
+%* *
\subsection{Errors}
-%* *
+%* *
%*********************************************************
\begin{code}
-noIfaceErr mod sty
- = ppBesides [ppStr "Could not find interface for ", ppQuote (pprModule sty mod)]
--- , ppStr " in"]) 4 (ppAboves (map ppStr dirs))
-
-cannaeReadFile file err sty
- = ppBesides [ppPStr SLIT("Failed in reading file: "), ppStr file, ppStr "; error=", ppStr (show err)]
+getDeclErr name
+ = vcat [ptext SLIT("Failed to find interface decl for") <+> quotes (ppr name),
+ ptext SLIT("from module") <+> quotes (ppr (nameModule name))
+ ]
+
+importDeclWarn name
+ = sep [ptext SLIT(
+ "Compiler tried to import decl from interface file with same name as module."),
+ ptext SLIT(
+ "(possible cause: module name clashes with interface file already in scope.)")
+ ] $$
+ hsep [ptext SLIT("name:"), quotes (ppr name)]
\end{code}
projects / ghc-hetmet.git / blobdiff