%
-% (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 (
- cacheInterface,
- readInterface,
- rnInterfaces,
- finalIfaceInfo,
- IfaceCache(..),
- VersionInfo(..),
- ParsedIface(..)
- ) where
+ getInterfaceExports,
+ getImportedInstDecls,
+ getSpecialInstModules, getDeferredDataDecls,
+ importDecl, recordSlurp,
+ getImportVersions, getSlurpedNames, getRnStats, getImportedFixities,
-import PreludeGlaST ( returnPrimIO, thenPrimIO,
- readVar, writeVar, MutableVar(..) )
+ checkUpToDate, loadHomeInterface,
-import Ubiq
+ getDeclBinders,
+ mkSearchPath
+ ) where
-import HsSyn
-import RdrHsSyn
-import RnHsSyn
+#include "HsVersions.h"
+import CmdLineOpts ( opt_PruneTyDecls, opt_PruneInstDecls,
+ opt_D_show_rn_imports, opt_IgnoreIfacePragmas
+ )
+import HsSyn ( HsDecl(..), TyClDecl(..), InstDecl(..), IfaceSig(..),
+ HsType(..), ConDecl(..), IE(..), ConDetails(..), Sig(..),
+ FixitySig(..),
+ hsDeclName, countTyClDecls, isDataDecl, nonFixitySigs
+ )
+import BasicTypes ( Version, NewOrData(..), IfaceFlavour(..) )
+import RdrHsSyn ( RdrNameHsDecl, RdrNameInstDecl, RdrNameTyClDecl,
+ RdrName(..), rdrNameOcc
+ )
+import RnEnv ( newImportedGlobalName, addImplicitOccsRn, pprAvail,
+ availName, availNames, addAvailToNameSet, ifaceFlavour
+ )
+import RnSource ( rnHsSigType )
import RnMonad
-import RnUtils ( RnEnv(..) )
+import RnHsSyn ( RenamedHsDecl )
+import ParseIface ( parseIface, IfaceStuff(..) )
+
+import FiniteMap ( FiniteMap, sizeFM, emptyFM, delFromFM,
+ lookupFM, addToFM, addToFM_C, addListToFM,
+ fmToList
+ )
+import Name ( Name {-instance NamedThing-}, OccName,
+ nameModule, moduleString, pprModule, isLocallyDefined,
+ isWiredInName, maybeWiredInTyConName, pprModule,
+ maybeWiredInIdName, nameUnique, NamedThing(..)
+ )
+import NameSet
+import Id ( idType, isDataConId_maybe )
+import DataCon ( dataConTyCon, dataConType )
+import TyCon ( TyCon, tyConDataCons, isSynTyCon, getSynTyConDefn )
+import Type ( namesOfType )
+import Var ( Id )
+import SrcLoc ( mkSrcLoc, SrcLoc )
+import PrelMods ( pREL_GHC )
+import PrelInfo ( cCallishTyKeys, thinAirModules )
+import Bag
+import Maybes ( MaybeErr(..), maybeToBool )
+import ListSetOps ( unionLists )
+import Outputable
+import Unique ( Unique )
+import StringBuffer ( StringBuffer, hGetStringBuffer )
+import FastString ( mkFastString )
+import Outputable
+
+import IO ( isDoesNotExistError )
+import List ( nub )
+
+\end{code}
+
+
+
+%*********************************************************
+%* *
+\subsection{Statistics}
+%* *
+%*********************************************************
+
+\begin{code}
+getRnStats :: [RenamedHsDecl] -> RnMG SDoc
+getRnStats all_decls
+ = getIfacesRn `thenRn` \ ifaces ->
+ let
+ n_mods = sizeFM (iModMap ifaces)
+
+ decls_imported = filter is_imported_decl all_decls
+
+ decls_read = [decl | (_, avail, decl, True) <- nameEnvElts (iDecls ifaces),
+ -- Data, newtype, and class decls are in the decls_fm
+ -- under multiple names; the tycon/class, and each
+ -- constructor/class op too.
+ -- The 'True' selects just the 'main' decl
+ not (isLocallyDefined (availName avail))
+ ]
+
+ (cd_rd, dd_rd, add_rd, nd_rd, and_rd, sd_rd, vd_rd, _) = count_decls decls_read
+ (cd_sp, dd_sp, add_sp, nd_sp, and_sp, sd_sp, vd_sp, id_sp) = count_decls decls_imported
+
+ (unslurped_insts, _) = iDefInsts ifaces
+ inst_decls_unslurped = length (bagToList unslurped_insts)
+ inst_decls_read = id_sp + inst_decls_unslurped
+
+ stats = vcat
+ [int n_mods <> text " interfaces read",
+ hsep [ int cd_sp, text "class decls imported, out of",
+ int cd_rd, text "read"],
+ hsep [ int dd_sp, text "data decls imported (of which", int add_sp,
+ text "abstractly), out of",
+ int dd_rd, text "read"],
+ hsep [ int nd_sp, text "newtype decls imported (of which", int and_sp,
+ text "abstractly), out of",
+ int nd_rd, text "read"],
+ hsep [int sd_sp, text "type synonym decls imported, out of",
+ int sd_rd, text "read"],
+ hsep [int vd_sp, text "value signatures imported, out of",
+ int vd_rd, text "read"],
+ hsep [int id_sp, text "instance decls imported, out of",
+ int inst_decls_read, text "read"]
+ ]
+ in
+ returnRn (hcat [text "Renamer stats: ", stats])
+
+is_imported_decl (DefD _) = False
+is_imported_decl (ValD _) = False
+is_imported_decl decl = not (isLocallyDefined (hsDeclName decl))
+
+count_decls decls
+ = -- pprTrace "count_decls" (ppr decls
+ --
+ -- $$
+ -- text "========="
+ -- $$
+ -- ppr imported_decls
+ -- ) $
+ (class_decls,
+ data_decls, abstract_data_decls,
+ newtype_decls, abstract_newtype_decls,
+ syn_decls,
+ val_decls,
+ inst_decls)
+ where
+ tycl_decls = [d | TyClD d <- decls]
+ (class_decls, data_decls, newtype_decls, syn_decls) = countTyClDecls tycl_decls
+ abstract_data_decls = length [() | TyData DataType _ _ _ [] _ _ _ <- tycl_decls]
+ abstract_newtype_decls = length [() | TyData NewType _ _ _ [] _ _ _ <- tycl_decls]
+
+ val_decls = length [() | SigD _ <- decls]
+ inst_decls = length [() | InstD _ <- decls]
+
+\end{code}
+
+%*********************************************************
+%* *
+\subsection{Loading a new interface file}
+%* *
+%*********************************************************
+
+\begin{code}
+loadHomeInterface :: SDoc -> Name -> RnMG Ifaces
+loadHomeInterface doc_str name
+ = loadInterface doc_str (nameModule name) (ifaceFlavour name)
+
+loadInterface :: SDoc -> Module -> IfaceFlavour -> RnMG Ifaces
+loadInterface doc_str load_mod as_source
+ = getIfacesRn `thenRn` \ ifaces ->
+ let
+ this_mod = iMod ifaces
+ mod_map = iModMap ifaces
+ (insts, tycls_names) = iDefInsts ifaces
+ in
+ -- CHECK WHETHER WE HAVE IT ALREADY
+ case lookupFM mod_map load_mod of {
+ Just (hif, _, _) | hif `as_good_as` as_source
+ -> -- Already in the cache; don't re-read it
+ returnRn ifaces ;
+ other ->
+
+ -- READ THE MODULE IN
+ findAndReadIface doc_str load_mod as_source `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_mod_map = addToFM mod_map load_mod (HiFile, 0, [])
+ new_ifaces = ifaces { iModMap = new_mod_map }
+ in
+ setIfacesRn new_ifaces `thenRn_`
+ failWithRn new_ifaces (noIfaceErr load_mod) ;
+
+ -- Found and parsed!
+ Just (ParsedIface _ mod_vers usages exports rd_inst_mods rd_decls rd_insts) ->
+
+ -- LOAD IT INTO Ifaces
+ -- NB: *first* we do loadDecl, so that the provenance of all the locally-defined
+ --- names is done correctly (notably, whether this is an .hi file or .hi-boot file).
+ -- If we do loadExport first the wrong info gets into the cache (unless we
+ -- explicitly tag each export which seems a bit of a bore)
+ foldlRn (loadDecl load_mod as_source)
+ (iDecls ifaces) rd_decls `thenRn` \ new_decls ->
+ foldlRn (loadFixDecl load_mod as_source)
+ (iFixes ifaces) rd_decls `thenRn` \ new_fixities ->
+ mapRn loadExport exports `thenRn` \ avails_s ->
+ foldlRn (loadInstDecl load_mod) insts rd_insts `thenRn` \ new_insts ->
+ let
+ mod_details = (as_source, mod_vers, concat avails_s)
+
+ -- Exclude this module from the "special-inst" modules
+ new_inst_mods = iInstMods ifaces `unionLists` (filter (/= this_mod) rd_inst_mods)
+
+ new_ifaces = ifaces { iModMap = addToFM mod_map load_mod mod_details,
+ iDecls = new_decls,
+ iFixes = new_fixities,
+ iDefInsts = (new_insts, tycls_names),
+ iInstMods = new_inst_mods }
+ in
+ setIfacesRn new_ifaces `thenRn_`
+ returnRn new_ifaces
+ }}
+
+as_good_as HiFile any = True
+as_good_as any HiBootFile = True
+as_good_as _ _ = False
+
+
+loadExport :: ExportItem -> RnMG [AvailInfo]
+loadExport (mod, hif, entities)
+ = mapRn load_entity entities
+ where
+ new_name occ = newImportedGlobalName mod occ hif
+
+ load_entity (Avail occ)
+ = new_name occ `thenRn` \ name ->
+ returnRn (Avail name)
+ load_entity (AvailTC occ occs)
+ = new_name occ `thenRn` \ name ->
+ mapRn new_name occs `thenRn` \ names ->
+ returnRn (AvailTC name names)
+
+
+loadFixDecl :: Module -> IfaceFlavour -> FixityEnv
+ -> (Version, RdrNameHsDecl)
+ -> RnMG FixityEnv
+loadFixDecl mod as_source fixity_env (version, FixD (FixitySig rdr_name fixity loc))
+ = -- Ignore the version; when the fixity changes the version of
+ -- its 'host' entity changes, so we don't need a separate version
+ -- number for fixities
+ new_implicit_name mod as_source rdr_name `thenRn` \ name ->
+ let
+ new_fixity_env = addToNameEnv fixity_env name (FixitySig name fixity loc)
+ in
+ returnRn new_fixity_env
+
+ -- Ignore the other sorts of decl
+loadFixDecl mod as_source fixity_env other_decl = returnRn fixity_env
+
+loadDecl :: Module -> IfaceFlavour -> DeclsMap
+ -> (Version, RdrNameHsDecl)
+ -> RnMG DeclsMap
+
+loadDecl mod as_source decls_map (version, decl)
+ = getDeclBinders new_name decl `thenRn` \ avail ->
+ getDeclSysBinders new_name decl `thenRn` \ sys_bndrs ->
+ let
+ main_name = availName avail
+ new_decls_map = foldl add_decl decls_map
+ [ (name, (version,avail,decl',name==main_name))
+ | name <- sys_bndrs ++ availNames avail]
+ add_decl decls_map (name, stuff)
+ = WARN( name `elemNameEnv` decls_map, ppr name )
+ addToNameEnv decls_map name stuff
+ in
+ returnRn new_decls_map
+ where
+ new_name rdr_name loc = new_implicit_name mod as_source rdr_name
+ {-
+ If a signature decl is being loaded, and optIgnoreIfacePragmas is on,
+ we toss away unfolding information.
+
+ Also, if the signature is loaded from a module we're importing from source,
+ we do the same. This is to avoid situations when compiling a pair of mutually
+ recursive modules, peering at unfolding info in the interface file of the other,
+ e.g., you compile A, it looks at B's interface file and may as a result change
+ its interface file. Hence, B is recompiled, maybe changing its interface file,
+ which will the unfolding info used in A to become invalid. Simple way out is to
+ just ignore unfolding info.
+ -}
+ decl' =
+ case decl of
+ SigD (IfaceSig name tp ls loc) | from_hi_boot || opt_IgnoreIfacePragmas ->
+ SigD (IfaceSig name tp [] loc)
+ _ -> decl
+
+ from_hi_boot = case as_source of
+ HiBootFile -> True
+ other -> False
+
+new_implicit_name mod as_source rdr_name
+ = newImportedGlobalName mod (rdrNameOcc rdr_name) as_source
+
+loadInstDecl :: Module
+ -> Bag IfaceInst
+ -> RdrNameInstDecl
+ -> RnMG (Bag IfaceInst)
+loadInstDecl mod_name insts decl@(InstDecl inst_ty binds uprags dfun_name src_loc)
+ =
+ -- Find out what type constructors and classes are "gates" for the
+ -- instance declaration. If all these "gates" are slurped in then
+ -- we should slurp the instance decl too.
+ --
+ -- We *don't* want to count names in the context part as gates, though.
+ -- For example:
+ -- instance Foo a => Baz (T a) where ...
+ --
+ -- Here the gates are Baz and T, but *not* Foo.
+ let
+ munged_inst_ty = case inst_ty of
+ HsForAllTy tvs cxt ty -> HsForAllTy tvs [] ty
+ other -> inst_ty
+ in
+ -- We find the gates by renaming the instance type with in a
+ -- and returning the free variables of the type
+ initRnMS emptyRnEnv mod_name vanillaInterfaceMode (
+ discardOccurrencesRn (rnHsSigType (text "an instance decl") munged_inst_ty)
+ ) `thenRn` \ (_, gate_names) ->
+ returnRn (((mod_name, decl), gate_names) `consBag` insts)
+
+vanillaInterfaceMode = InterfaceMode Compulsory
+\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 HiFile `thenRn` \ read_result ->
+
+ -- CHECK WHETHER WE HAVE IT ALREADY
+ case read_result of
+ Nothing -> -- Old interface file not found, so we'd better bail out
+ traceRn (sep [ptext SLIT("Didnt find old iface"),
+ pprModule mod_name]) `thenRn_`
+ returnRn False
+
+ Just (ParsedIface _ _ usages _ _ _ _)
+ -> -- Found it, so now check it
+ checkModUsage usages
+ where
+ -- Only look in current directory, with suffix .hi
+ doc_str = sep [ptext SLIT("need usage info from"), pprModule mod_name]
+
+checkModUsage [] = returnRn True -- Yes! Everything is up to date!
+
+checkModUsage ((mod, hif, old_mod_vers, whats_imported) : rest)
+ = loadInterface doc_str mod hif `thenRn` \ ifaces ->
+ let
+ maybe_new_mod_vers = lookupFM (iModMap ifaces) mod
+ Just (_, new_mod_vers, _) = maybe_new_mod_vers
+ in
+ -- If we can't find a version number for the old module then
+ -- bail out saying things aren't up to date
+ if not (maybeToBool maybe_new_mod_vers) then
+ traceRn (sep [ptext SLIT("Can't find version number for module"), pprModule mod]) `thenRn_`
+ returnRn False
+ else
+
+ -- If the module version hasn't changed, just move on
+ if new_mod_vers == old_mod_vers then
+ traceRn (sep [ptext SLIT("Module version unchanged:"), pprModule mod]) `thenRn_`
+ checkModUsage rest
+ else
+ traceRn (sep [ptext SLIT("Module version has changed:"), pprModule mod]) `thenRn_`
+
+ -- Module version changed, so check entities inside
+
+ -- If the usage info wants to say "I imported everything from this module"
+ -- it does so by making whats_imported equal to Everything
+ -- In that case, we must recompile
+ case whats_imported of {
+ Everything -> traceRn (ptext SLIT("...and I needed the whole module")) `thenRn_`
+ returnRn False; -- Bale out
+
+ Specifically old_local_vers ->
+
+ -- Non-empty usage list, so check item by item
+ checkEntityUsage mod (iDecls ifaces) old_local_vers `thenRn` \ up_to_date ->
+ if up_to_date then
+ traceRn (ptext SLIT("...but the bits I use haven'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 = sep [ptext SLIT("need version info for"), pprModule mod]
+
+
+checkEntityUsage mod decls []
+ = returnRn True -- Yes! All up to date!
+
+checkEntityUsage mod decls ((occ_name,old_vers) : rest)
+ = newImportedGlobalName mod occ_name HiFile `thenRn` \ name ->
+ case lookupNameEnv decls name of
+
+ Nothing -> -- We used it before, but it ain't there now
+ putDocRn (sep [ptext SLIT("No longer exported:"), ppr name]) `thenRn_`
+ returnRn False
+
+ Just (new_vers,_,_,_) -- It's there, but is it up to date?
+ | new_vers == old_vers
+ -- Up to date, so check the rest
+ -> checkEntityUsage mod decls rest
+
+ | otherwise
+ -- Out of date, so bale out
+ -> putDocRn (sep [ptext SLIT("Out of date:"), ppr name]) `thenRn_`
+ returnRn False
+\end{code}
+
+
+%*********************************************************
+%* *
+\subsection{Getting in a declaration}
+%* *
+%*********************************************************
+
+\begin{code}
+importDecl :: Occurrence -> RnSMode -> RnMG (Maybe RdrNameHsDecl)
+ -- Returns Nothing for a wired-in or already-slurped decl
+
+importDecl (name, loc) mode
+ = checkSlurped name `thenRn` \ already_slurped ->
+ if already_slurped then
+-- traceRn (sep [text "Already slurped:", ppr name]) `thenRn_`
+ returnRn Nothing -- Already dealt with
+ else
+ if isWiredInName name then
+ getWiredInDecl name mode
+ else
+ getIfacesRn `thenRn` \ ifaces ->
+ let
+ mod = nameModule name
+ in
+ if mod == iMod ifaces then -- Don't bring in decls from
+ addWarnRn (importDeclWarn mod name loc) `thenRn_`
+-- pprTrace "importDecl wierdness:" (ppr name) $
+ returnRn Nothing -- the renamed module's own interface file
+ --
+ else
+ getNonWiredInDecl name loc mode
+\end{code}
+
+\begin{code}
+getNonWiredInDecl :: Name -> SrcLoc -> RnSMode -> RnMG (Maybe RdrNameHsDecl)
+getNonWiredInDecl needed_name loc mode
+ = traceRn doc_str `thenRn_`
+ loadHomeInterface doc_str needed_name `thenRn` \ ifaces ->
+ case lookupNameEnv (iDecls ifaces) needed_name of
+
+ -- Special case for data/newtype type declarations
+ Just (version, avail, TyClD tycl_decl, _) | isDataDecl tycl_decl
+ -> getNonWiredDataDecl needed_name version avail tycl_decl `thenRn` \ (avail', maybe_decl) ->
+ recordSlurp (Just version) necessity avail' `thenRn_`
+ returnRn maybe_decl
+
+ Just (version,avail,decl,_)
+ -> recordSlurp (Just version) necessity avail `thenRn_`
+ returnRn (Just decl)
+
+ Nothing -> -- Can happen legitimately for "Optional" occurrences
+ case necessity of {
+ Optional -> addWarnRn (getDeclWarn needed_name loc);
+ other -> addErrRn (getDeclErr needed_name loc)
+ } `thenRn_`
+ returnRn Nothing
+ where
+ necessity = modeToNecessity mode
+ doc_str = sep [ptext SLIT("need decl for"), ppr needed_name, ptext SLIT("needed at"), ppr loc]
+\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,
+
+ * 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.
+
+ * similarly for synonum type constructor
+
+ * if the wired-in name is another wired-in Id, it marks as "occurrences"
+ the free vars of the Id's type.
+
+ * it loads the interface file for the wired-in thing for the
+ sole purpose of making sure that its instance declarations are available
+
+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 mode
+ = initRnMS emptyRnEnv mod_name new_mode
+ get_wired `thenRn` \ avail ->
+ recordSlurp Nothing necessity avail `thenRn_`
+
+ -- Force in the home module in case it has instance decls for
+ -- the thing we are interested in.
+ --
+ -- Mini hack 1: no point for non-tycons/class; 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
+ --
+ -- NB: We *must* look at the availName of the slurped avail,
+ -- not the name passed to getWiredInDecl! Why? Because if a data constructor
+ -- or class op is passed to getWiredInDecl we'll pull in the whole data/class
+ -- decl, and recordSlurp will record that fact. But since the data constructor
+ -- isn't a tycon/class we won't force in the home module. And even if the
+ -- type constructor/class comes along later, loadDecl will say that it's already
+ -- been slurped, so getWiredInDecl won't even be called. Pretty obscure bug, this was.
+ let
+ main_name = availName avail
+ main_is_tc = case avail of { AvailTC _ _ -> True; Avail _ -> False }
+ mod = nameModule main_name
+ doc_str = sep [ptext SLIT("need home module for wired in thing"), ppr name]
+ in
+ (if not main_is_tc || mod == pREL_GHC then
+ returnRn ()
+ else
+ loadHomeInterface doc_str main_name `thenRn_`
+ returnRn ()
+ ) `thenRn_`
+
+ returnRn Nothing -- No declaration to process further
+ where
+ necessity = modeToNecessity mode
+ new_mode = case mode of
+ InterfaceMode _ -> mode
+ SourceMode -> vanillaInterfaceMode
+
+ get_wired | is_tycon -- ... a type constructor
+ = get_wired_tycon the_tycon
+
+ | maybeToBool maybe_data_con -- ... a wired-in data constructor
+ = get_wired_tycon (dataConTyCon data_con)
-import Bag ( emptyBag )
-import ErrUtils ( Error(..), Warning(..) )
-import FiniteMap ( emptyFM, lookupFM, addToFM )
-import Pretty
-import Maybes ( MaybeErr(..) )
-import Util ( panic )
+ | otherwise -- ... a wired-in non data-constructor
+ = get_wired_id the_id
+ mod_name = nameModule 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
+ maybe_data_con = isDataConId_maybe the_id
+ Just data_con = maybe_data_con
+
+
+get_wired_id id
+ = addImplicitOccsRn id_mentions `thenRn_`
+ returnRn (Avail (getName id))
+ where
+ id_mentions = nameSetToList (namesOfType ty)
+ ty = idType id
+
+get_wired_tycon tycon
+ | isSynTyCon tycon
+ = addImplicitOccsRn (nameSetToList mentioned) `thenRn_`
+ returnRn (AvailTC tc_name [tc_name])
+ where
+ tc_name = getName tycon
+ (tyvars,ty) = getSynTyConDefn tycon
+ mentioned = namesOfType ty `minusNameSet` mkNameSet (map getName tyvars)
+
+get_wired_tycon tycon
+ | otherwise -- data or newtype
+ = addImplicitOccsRn (nameSetToList mentioned) `thenRn_`
+ returnRn (AvailTC tycon_name (tycon_name : map getName data_cons))
+ where
+ tycon_name = getName tycon
+ data_cons = tyConDataCons tycon
+ mentioned = foldr (unionNameSets . namesOfType . dataConType) emptyNameSet data_cons
+\end{code}
+
+
+
+%*********************************************************
+%* *
+\subsection{Getting what a module exports}
+%* *
+%*********************************************************
+
+\begin{code}
+getInterfaceExports :: Module -> IfaceFlavour -> RnMG Avails
+getInterfaceExports mod as_source
+ = loadInterface doc_str mod as_source `thenRn` \ ifaces ->
+ case lookupFM (iModMap ifaces) 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 (_, _, avails) -> returnRn avails
+ where
+ doc_str = sep [pprModule mod, ptext SLIT("is directly imported")]
+\end{code}
+
+
+%*********************************************************
+%* *
+\subsection{Data type declarations are handled specially}
+%* *
+%*********************************************************
+
+Data type declarations get special treatment. If we import a data type decl
+with all its constructors, we end up importing all the types mentioned in
+the constructors' signatures, and hence {\em their} data type decls, and so on.
+In effect, we get the transitive closure of data type decls. Worse, this drags
+in tons on instance decls, and their unfoldings, and so on.
+
+If only the type constructor is mentioned, then all this is a waste of time.
+If any of the data constructors are mentioned then we really have to
+drag in the whole declaration.
+
+So when we import the type constructor for a @data@ or @newtype@ decl, we
+put it in the "deferred data/newtype decl" pile in Ifaces. Right at the end
+we slurp these decls, if they havn't already been dragged in by an occurrence
+of a constructor.
+
+\begin{code}
+getNonWiredDataDecl needed_name
+ version
+ avail@(AvailTC tycon_name _)
+ ty_decl@(TyData new_or_data context tycon tyvars condecls derivings pragmas src_loc)
+ | needed_name == tycon_name
+ && opt_PruneTyDecls
+ -- don't prune newtypes, as the code generator may
+ -- want to peer inside a newtype type constructor
+ -- (ClosureInfo.fun_result_ty is the culprit.)
+ && not (new_or_data == NewType)
+ && not (nameUnique needed_name `elem` cCallishTyKeys)
+ -- Hack! Don't prune these tycons whose constructors
+ -- the desugarer must be able to see when desugaring
+ -- a CCall. Ugh!
+
+ = -- Need the type constructor; so put it in the deferred set for now
+ getIfacesRn `thenRn` \ ifaces ->
+ let
+ deferred_data_decls = iDefData ifaces
+ new_ifaces = ifaces {iDefData = new_deferred_data_decls}
+
+ no_constr_ty_decl = TyData new_or_data [] tycon tyvars [] derivings pragmas src_loc
+ new_deferred_data_decls = addToNameEnv deferred_data_decls tycon_name
+ (nameModule tycon_name, no_constr_ty_decl)
+ -- Nota bene: we nuke both the constructors and the context in the deferred decl.
+ -- If we don't nuke the context then renaming the deferred data decls can give
+ -- new unresolved names (for the classes). This could be handled, but there's
+ -- no point. If the data type is completely abstract then we aren't interested
+ -- its context.
+ in
+ setIfacesRn new_ifaces `thenRn_`
+ returnRn (AvailTC tycon_name [tycon_name], Nothing)
+
+ | otherwise
+ = -- Need a data constructor, so delete the data decl from the deferred set if it's there
+ getIfacesRn `thenRn` \ ifaces ->
+ let
+ deferred_data_decls = iDefData ifaces
+ new_ifaces = ifaces {iDefData = new_deferred_data_decls}
+
+ new_deferred_data_decls = delFromNameEnv deferred_data_decls tycon_name
+ in
+ setIfacesRn new_ifaces `thenRn_`
+ returnRn (avail, Just (TyClD ty_decl))
+\end{code}
+
+\begin{code}
+getDeferredDataDecls :: RnMG [(Module, RdrNameTyClDecl)]
+getDeferredDataDecls
+ = getIfacesRn `thenRn` \ ifaces ->
+ let
+ deferred_list = nameEnvElts (iDefData ifaces)
+ trace_msg = hang (text "Slurping abstract data/newtype decls for: ")
+ 4 (ppr (map fst deferred_list))
+ in
+ traceRn trace_msg `thenRn_`
+ returnRn deferred_list
+\end{code}
+
+
+%*********************************************************
+%* *
+\subsection{Instance declarations are handled specially}
+%* *
+%*********************************************************
+
+\begin{code}
+getImportedInstDecls :: RnMG [(Module,RdrNameInstDecl)]
+getImportedInstDecls
+ = -- First load any special-instance modules that aren't aready loaded
+ getSpecialInstModules `thenRn` \ inst_mods ->
+ mapRn load_it inst_mods `thenRn_`
+
+ -- 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
+ (insts, tycls_names) = iDefInsts ifaces
+
+ -- An instance decl is ungated if all its gates have been slurped
+ select_ungated :: IfaceInst -- A gated inst decl
+
+ -> ([(Module, RdrNameInstDecl)], [IfaceInst]) -- Accumulator
+
+ -> ([(Module, RdrNameInstDecl)], -- The ungated ones
+ [IfaceInst]) -- Still gated, but with
+ -- depeleted gates
+ select_ungated (decl,gates) (ungated_decls, gated_decls)
+ | isEmptyNameSet remaining_gates
+ = (decl : ungated_decls, gated_decls)
+ | otherwise
+ = (ungated_decls, (decl, remaining_gates) : gated_decls)
+ where
+ remaining_gates = gates `minusNameSet` tycls_names
+
+ (un_gated_insts, still_gated_insts) = foldrBag select_ungated ([], []) insts
+
+ new_ifaces = ifaces {iDefInsts = (listToBag still_gated_insts, tycls_names)}
+ -- NB: don't throw away tycls_names;
+ -- we may comre across more instance decls
+ in
+ traceRn (sep [text "getInstDecls:", fsep (map ppr (nameSetToList tycls_names))]) `thenRn_`
+ setIfacesRn new_ifaces `thenRn_`
+ returnRn un_gated_insts
+ where
+ load_it mod = loadInterface (doc_str mod) mod HiFile
+ doc_str mod = sep [pprModule mod, ptext SLIT("is a special-instance module")]
+
+
+getSpecialInstModules :: RnMG [Module]
+getSpecialInstModules
+ = getIfacesRn `thenRn` \ ifaces ->
+ returnRn (iInstMods ifaces)
+
+getImportedFixities :: RnMG FixityEnv
+getImportedFixities
+ = getIfacesRn `thenRn` \ ifaces ->
+ returnRn (iFixes ifaces)
+\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:
+ - anything reachable from its body code
+ - any module exported with a "module Foo".
+
+Why the latter? 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.
+
+What about this?
+ module A( f, g ) where module B( f ) where
+ import B( f ) f = h 3
+ g = ... h = ...
+
+Should we record B.f in A's usages? In fact we don't. Certainly, if
+anything about B.f changes than anyone who imports A should be recompiled;
+they'll get an early exit if they don't use B.f. However, 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. So there are two things going on when compiling module A:
+
+1. Are A.o and A.hi correct? Then we can bale out early.
+2. Should modules that import A be recompiled?
+
+For (1) it is slightly harmful to record B.f in A's usages, because a change in
+B.f's version will provoke full recompilation of A, producing an identical A.o,
+and A.hi differing only in its usage-version of B.f (which isn't used by any importer).
+
+For (2), because of the tricky B.h question above, we ensure that A.hi is touched
+(even if identical to its previous version) if A's recompilation was triggered by
+an imported .hi file date change. Given that, there's no need to record B.f in
+A's usages.
+
+On the other hand, if A exports "module B" then we *do* count module B among
+A's usages, because we must recompile A to ensure that A.hi changes appropriately.
+
+\begin{code}
+getImportVersions :: Module -- Name of this module
+ -> Maybe [IE any] -- Export list for this module
+ -> RnMG (VersionInfo Name) -- Version info for these names
+
+getImportVersions this_mod exports
+ = getIfacesRn `thenRn` \ ifaces ->
+ let
+ mod_map = iModMap ifaces
+ imp_names = iVSlurp ifaces
+
+ -- mv_map groups together all the things imported from a particular module.
+ mv_map, mv_map_mod :: FiniteMap Module (WhatsImported Name)
+
+ mv_map_mod = foldl add_mod emptyFM export_mods
+ -- mv_map_mod records all the modules that have a "module M"
+ -- in this module's export list with an "Everything"
+
+ mv_map = foldl add_mv mv_map_mod imp_names
+ -- mv_map adds the version numbers of things exported individually
+
+ mk_version_info (mod, local_versions)
+ = case lookupFM mod_map mod of
+ Just (hif, version, _) -> (mod, hif, version, local_versions)
+ in
+ returnRn (map mk_version_info (fmToList mv_map))
+ where
+ export_mods = case exports of
+ Nothing -> []
+ Just es -> [mod | IEModuleContents mod <- es, mod /= this_mod]
+
+ add_mv mv_map v@(name, version)
+ = addToFM_C add_item mv_map mod (Specifically [v])
+ where
+ mod = nameModule name
+
+ add_item Everything _ = Everything
+ add_item (Specifically xs) _ = Specifically (v:xs)
+
+ add_mod mv_map mod = addToFM mv_map mod Everything
+\end{code}
+
+\begin{code}
+checkSlurped name
+ = getIfacesRn `thenRn` \ ifaces ->
+ returnRn (name `elemNameSet` iSlurp ifaces)
+
+getSlurpedNames :: RnMG NameSet
+getSlurpedNames
+ = getIfacesRn `thenRn` \ ifaces ->
+ returnRn (iSlurp ifaces)
+
+recordSlurp maybe_version necessity avail
+ = {- traceRn (hsep [text "Record slurp:", pprAvail avail,
+ -- NB PprForDebug prints export flag, which is too
+ -- strict; it's a knot-tied thing in RnNames
+ case necessity of {Compulsory -> text "comp"; Optional -> text "opt" } ]) `thenRn_`
+ -}
+ getIfacesRn `thenRn` \ ifaces ->
+ let
+ Ifaces { iSlurp = slurped_names,
+ iVSlurp = imp_names,
+ iDefInsts = (insts, tycls_names) } = ifaces
+
+ new_slurped_names = addAvailToNameSet slurped_names avail
+
+ new_imp_names = case maybe_version of
+ Just version -> (availName avail, version) : imp_names
+ Nothing -> imp_names
+
+ -- Add to the names that will let in instance declarations;
+ -- but only (a) if it's a type/class
+ -- (b) if it's compulsory (unless the test flag opt_PruneInstDecls is off)
+ new_tycls_names = case avail of
+ AvailTC tc _ | not opt_PruneInstDecls ||
+ case necessity of {Optional -> False; Compulsory -> True }
+ -> tycls_names `addOneToNameSet` tc
+ otherwise -> tycls_names
+
+ new_ifaces = ifaces { iSlurp = new_slurped_names,
+ iVSlurp = new_imp_names,
+ iDefInsts = (insts, new_tycls_names) }
+ in
+ setIfacesRn new_ifaces
\end{code}
+%*********************************************************
+%* *
+\subsection{Getting binders out of a declaration}
+%* *
+%*********************************************************
+
+@getDeclBinders@ returns the names for a @RdrNameHsDecl@.
+It's used for both source code (from @availsFromDecl@) and interface files
+(from @loadDecl@).
+
+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 IfaceCache = MutableVar _RealWorld (FiniteMap Module ParsedIface,
- FiniteMap Module FAST_STRING)
+getDeclBinders :: (RdrName -> SrcLoc -> RnMG Name) -- New-name function
+ -> RdrNameHsDecl
+ -> RnMG AvailInfo
+
+getDeclBinders new_name (TyClD (TyData _ _ tycon _ condecls _ _ src_loc))
+ = new_name tycon src_loc `thenRn` \ tycon_name ->
+ getConFieldNames new_name condecls `thenRn` \ sub_names ->
+ returnRn (AvailTC tycon_name (tycon_name : nub sub_names))
+ -- The "nub" is because getConFieldNames can legitimately return duplicates,
+ -- when a record declaration has the same field in multiple constructors
+
+getDeclBinders new_name (TyClD (TySynonym tycon _ _ src_loc))
+ = new_name tycon src_loc `thenRn` \ tycon_name ->
+ returnRn (AvailTC tycon_name [tycon_name])
+
+getDeclBinders new_name (TyClD (ClassDecl _ cname _ sigs _ _ tname dname src_loc))
+ = new_name cname src_loc `thenRn` \ class_name ->
-data ParsedIface = ParsedIface
+ -- Record the names for the class ops
+ let
+ -- ignoring fixity declarations
+ nonfix_sigs = nonFixitySigs sigs
+ in
+ mapRn (getClassOpNames new_name) nonfix_sigs `thenRn` \ sub_names ->
+ returnRn (AvailTC class_name (class_name : sub_names))
-cacheInterface :: IfaceCache -> Module
- -> PrimIO (MaybeErr ParsedIface Error)
+getDeclBinders new_name (SigD (IfaceSig var ty prags src_loc))
+ = new_name var src_loc `thenRn` \ var_name ->
+ returnRn (Avail var_name)
-cacheInterface iface_var mod
- = readVar iface_var `thenPrimIO` \ (iface_fm, file_fm) ->
- case lookupFM iface_fm mod of
- Just iface -> returnPrimIO (Succeeded iface)
- Nothing ->
- case lookupFM file_fm mod of
- Nothing -> returnPrimIO (Failed (noIfaceErr mod))
- Just file ->
- readInterface file mod `thenPrimIO` \ read_iface ->
- case read_iface of
- Failed err -> returnPrimIO (Failed err)
- Succeeded iface ->
- let
- iface_fm' = addToFM iface_fm mod iface
- in
- writeVar iface_var (iface_fm', file_fm) `thenPrimIO` \ _ ->
- returnPrimIO (Succeeded iface)
+getDeclBinders new_name (FixD _) = returnRn NotAvailable
+getDeclBinders new_name (ForD _) = returnRn NotAvailable
+getDeclBinders new_name (DefD _) = returnRn NotAvailable
+getDeclBinders new_name (InstD _) = returnRn NotAvailable
+
+----------------
+getConFieldNames new_name (ConDecl con _ _ (RecCon 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)
+
+getConFieldNames new_name (ConDecl con _ _ condecl src_loc : rest)
+ = new_name con src_loc `thenRn` \ n ->
+ (case condecl of
+ NewCon _ (Just f) ->
+ new_name f src_loc `thenRn` \ new_f ->
+ returnRn [n,new_f]
+ _ -> returnRn [n]) `thenRn` \ nn ->
+ getConFieldNames new_name rest `thenRn` \ ns ->
+ returnRn (nn ++ ns)
+
+getConFieldNames new_name [] = returnRn []
+
+getClassOpNames new_name (ClassOpSig op _ _ src_loc) = new_name op src_loc
+\end{code}
+@getDeclSysBinders@ gets the implicit binders introduced by a decl.
+A the moment that's just the tycon and datacon that come with a class decl.
+They aren'te returned by getDeclBinders because they aren't in scope;
+but they should be put into the DeclsMap of this module.
-readInterface :: FAST_STRING -> Module
- -> PrimIO (MaybeErr ParsedIface Error)
+\begin{code}
+getDeclSysBinders new_name (TyClD (ClassDecl _ cname _ sigs _ _ tname dname src_loc))
+ = new_name dname src_loc `thenRn` \ datacon_name ->
+ new_name tname src_loc `thenRn` \ tycon_name ->
+ returnRn [tycon_name, datacon_name]
-readInterface file mod = panic "readInterface"
+getDeclSysBinders new_name other_decl
+ = returnRn []
\end{code}
+%*********************************************************
+%* *
+\subsection{Reading an interface file}
+%* *
+%*********************************************************
\begin{code}
-rnInterfaces ::
- IfaceCache -- iface cache
- -> RnEnv -- original name env
- -> UniqSupply
- -> RenamedHsModule -- module to extend with iface decls
- -> [RnName] -- imported names required
- -> PrimIO (RenamedHsModule, -- extended module
- ImplicitEnv, -- implicit names required
- Bag Error,
- Bag Warning)
+findAndReadIface :: SDoc -> Module
+ -> IfaceFlavour
+ -> RnMG (Maybe ParsedIface)
+ -- Nothing <=> file not found, or unreadable, or illegible
+ -- Just x <=> successfully found and parsed
+findAndReadIface doc_str mod_name as_source
+ = traceRn trace_msg `thenRn_`
+ -- we keep two maps for interface files,
+ -- one for 'normal' ones, the other for .hi-boot files,
+ -- hence the need to signal which kind we're interested.
+ getModuleHiMap as_source `thenRn` \ himap ->
+ case (lookupFM himap (moduleString mod_name)) of
+ -- Found the file
+ Just fpath -> readIface fpath
+ -- Hack alert! When compiling PrelBase we have to load the
+ -- decls for packCString# and friends; they are 'thin-air' Ids
+ -- (see PrelInfo.lhs). So if we don't find the HiFile we quietly
+ -- look for a .hi-boot file instead, and use that
+ Nothing | thinAirLoop mod_name as_source
+ -> findAndReadIface doc_str mod_name HiBootFile
+ | otherwise
+ -> traceRn (ptext SLIT("...failed")) `thenRn_`
+ returnRn Nothing
+ where
+ thinAirLoop mod_name HiFile = mod_name `elem` thinAirModules
+ thinAirLoop mod_name hif = False
-rnInterfaces iface_var occ_env us rn_module todo
- = returnPrimIO (rn_module, (emptyFM, emptyFM), emptyBag, emptyBag)
+ trace_msg = sep [hsep [ptext SLIT("Reading"),
+ case as_source of { HiBootFile -> ptext SLIT("[boot]"); other -> empty},
+ ptext SLIT("interface for"),
+ pprModule mod_name <> semi],
+ nest 4 (ptext SLIT("reason:") <+> doc_str)]
\end{code}
+@readIface@ tries just the one file.
\begin{code}
-finalIfaceInfo ::
- IfaceCache -- iface cache
- -> [RnName] -- all imported names required
- -> [Module] -- directly imported modules
- -> PrimIO (VersionInfo, -- info about version numbers
- [Module]) -- special instance modules
+readIface :: String -> RnMG (Maybe ParsedIface)
+ -- Nothing <=> file not found, or unreadable, or illegible
+ -- Just x <=> successfully found and parsed
+readIface file_path
+ = ioToRnMG (hGetStringBuffer file_path) `thenRn` \ read_result ->
+ case read_result of
+ Right contents ->
+ case parseIface contents (mkSrcLoc (mkFastString file_path) 1) of
+ Failed err -> failWithRn Nothing err
+ Succeeded (PIface iface) ->
+ if opt_D_show_rn_imports then
+ putDocRn (hcat[ptext SLIT("Read "), text file_path]) `thenRn_`
+ returnRn (Just iface)
+ else
+ returnRn (Just iface)
+
+ Left err ->
+ if isDoesNotExistError err then
+ returnRn Nothing
+ else
+ failWithRn Nothing (cannaeReadFile file_path err)
+\end{code}
-type VersionInfo = [(Module, Version, [(FAST_STRING, Version)])]
+%*********************************************************
+%* *
+\subsection{Utils}
+%* *
+%*********************************************************
-finalIfaceInfo iface_var imps_reqd imp_mods
- = returnPrimIO ([], [])
+@mkSearchPath@ takes a string consisting of a colon-separated list
+of directories and corresponding suffixes, and turns it into a list
+of (directory, suffix) pairs. For example:
+
+\begin{verbatim}
+ mkSearchPath "foo%.hi:.%.p_hi:baz%.mc_hi"
+ = [("foo",".hi"),( ".", ".p_hi"), ("baz",".mc_hi")]
+\begin{verbatim}
+
+\begin{code}
+mkSearchPath :: Maybe String -> SearchPath
+mkSearchPath Nothing = [(".",".hi")]
+mkSearchPath (Just s)
+ = go s
+ where
+ go "" = []
+ go s =
+ case span (/= '%') s of
+ (dir,'%':rs) ->
+ case span (/= ':') rs of
+ (hisuf,_:rest) -> (dir,hisuf):go rest
+ (hisuf,[]) -> [(dir,hisuf)]
\end{code}
+%*********************************************************
+%* *
+\subsection{Errors}
+%* *
+%*********************************************************
\begin{code}
-noIfaceErr mod sty
- = ppCat [ppStr "Could not find interface for", ppPStr mod]
+noIfaceErr filename
+ = hcat [ptext SLIT("Could not find valid interface file "),
+ quotes (pprModule filename)]
+
+cannaeReadFile file err
+ = hcat [ptext SLIT("Failed in reading file: "),
+ text file,
+ ptext SLIT("; error="),
+ text (show err)]
+
+getDeclErr name loc
+ = sep [ptext SLIT("Failed to find interface decl for") <+> quotes (ppr name),
+ ptext SLIT("needed at") <+> ppr loc]
+
+getDeclWarn name loc
+ = sep [ptext SLIT("Failed to find (optional) interface decl for") <+> quotes (ppr name),
+ ptext SLIT("desired at") <+> ppr loc]
+
+importDeclWarn mod name loc
+ = 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("Interface:"), quotes (pprModule mod), comma, ptext SLIT("name:"), quotes (ppr name),
+ comma, ptext SLIT("desired at:"), ppr loc
+ ]
+
\end{code}