2 % (c) The GRASP/AQUA Project, Glasgow University, 1993-1996
4 \section[MkIface]{Print an interface for a module}
13 #include "HsVersions.h"
15 import IO ( Handle, hPutStr, openFile,
16 hClose, hPutStrLn, IOMode(..) )
19 import RdrHsSyn ( RdrName(..) )
20 import RnHsSyn ( RenamedHsModule )
21 import BasicTypes ( Fixity(..), FixityDirection(..), NewOrData(..), IfaceFlavour(..),
25 import RnEnv ( availName, ifaceFlavour )
27 import TcInstUtil ( InstInfo(..) )
28 import WorkWrap ( getWorkerIdAndCons )
31 import Id ( idType, dataConRawArgTys, dataConFieldLabels,
32 getIdInfo, getInlinePragma, omitIfaceSigForId,
33 dataConStrictMarks, StrictnessMark(..),
34 IdSet, idSetToList, unionIdSets, unitIdSet, minusIdSet,
35 isEmptyIdSet, elementOfIdSet, emptyIdSet, mkIdSet,
40 import IdInfo ( IdInfo, StrictnessInfo, ArityInfo,
41 arityInfo, ppArityInfo, strictnessInfo, ppStrictnessInfo,
42 bottomIsGuaranteed, workerExists,
44 import PragmaInfo ( PragmaInfo(..) )
45 import CoreSyn ( CoreExpr, CoreBinding, GenCoreExpr, GenCoreBinding(..) )
46 import CoreUnfold ( calcUnfoldingGuidance, UnfoldingGuidance(..), Unfolding )
47 import FreeVars ( addExprFVs )
48 import Name ( isLocallyDefined, isWiredInName, modAndOcc, nameModule, pprOccName,
49 OccName, occNameString, nameOccName, nameString, isExported,
50 Name {-instance NamedThing-}, Provenance, NamedThing(..)
52 import TyCon ( TyCon, getSynTyConDefn, isSynTyCon, isNewTyCon, isAlgTyCon,
53 tyConTheta, tyConTyVars, tyConDataCons
55 import Class ( Class, classBigSig )
56 import FieldLabel ( fieldLabelName, fieldLabelType )
57 import Type ( mkSigmaTy, splitSigmaTy, mkDictTy,
58 mkTyVarTys, Type, ThetaType
61 import PprEnv -- not sure how much...
63 import PprCore ( pprIfaceUnfolding )
65 import Bag ( bagToList, isEmptyBag )
66 import Maybes ( catMaybes, maybeToBool )
67 import FiniteMap ( emptyFM, addToFM, addToFM_C, lookupFM, fmToList, eltsFM, FiniteMap )
68 import UniqFM ( UniqFM, lookupUFM, listToUFM )
69 import Util ( sortLt, zipWithEqual, zipWith3Equal, mapAccumL )
73 We have a function @startIface@ to open the output file and put
74 (something like) ``interface Foo'' in it. It gives back a handle
75 for subsequent additions to the interface file.
77 We then have one-function-per-block-of-interface-stuff, e.g.,
78 @ifaceExportList@ produces the @__exports__@ section; it appends
79 to the handle provided by @startIface@.
83 -> IO (Maybe Handle) -- Nothing <=> don't do an interface
85 ifaceMain :: Maybe Handle
90 ifaceDecls :: Maybe Handle
93 -> [Id] -- Ids used at code-gen time; they have better pragma info!
94 -> [CoreBinding] -- In dependency order, later depend on earlier
97 endIface :: Maybe Handle -> IO ()
102 = case opt_ProduceHi of
103 Nothing -> return Nothing -- not producing any .hi file
105 if_hdl <- openFile fn WriteMode
106 hPutStrLn if_hdl ("_interface_ "++ _UNPK_ mod ++ ' ':show (PROJECTVERSION :: Int))
109 endIface Nothing = return ()
110 endIface (Just if_hdl) = hPutStr if_hdl "\n" >> hClose if_hdl
115 ifaceMain Nothing iface_stuff = return ()
116 ifaceMain (Just if_hdl)
117 (import_usages, ExportEnv avails fixities, instance_modules)
119 ifaceInstanceModules if_hdl instance_modules >>
120 ifaceUsages if_hdl import_usages >>
121 ifaceExports if_hdl avails >>
122 ifaceFixities if_hdl fixities >>
125 ifaceDecls Nothing tycons classes inst_info final_ids simplified = return ()
126 ifaceDecls (Just hdl)
130 | null_decls = return ()
131 -- You could have a module with just (re-)exports/instances in it
133 = ifaceInstances hdl inst_infos >>= \ needed_ids ->
134 hPutStr hdl "_declarations_\n" >>
135 ifaceClasses hdl classes >>
136 ifaceTyCons hdl tycons >>
137 ifaceBinds hdl needed_ids final_ids binds >>
140 null_decls = null binds &&
143 isEmptyBag inst_infos
147 ifaceUsages if_hdl import_usages
148 = hPutStr if_hdl "_usages_\n" >>
149 hPutCol if_hdl upp_uses (sortLt lt_imp_vers import_usages)
151 upp_uses (m, hif, mv, whats_imported)
152 = hsep [pprModule m, pp_hif hif, int mv, ptext SLIT("::"),
153 upp_import_versions whats_imported
156 -- Importing the whole module is indicated by an empty list
157 upp_import_versions Everything = empty
159 -- For imported versions we do print the version number
160 upp_import_versions (Specifically nvs)
161 = hsep [ hsep [ppr_unqual_name n, int v] | (n,v) <- sort_versions nvs ]
163 ifaceInstanceModules if_hdl [] = return ()
164 ifaceInstanceModules if_hdl imods
165 = hPutStr if_hdl "_instance_modules_\n" >>
166 printForIface if_hdl (hsep (map ptext (sortLt (<) imods))) >>
169 ifaceExports if_hdl [] = return ()
170 ifaceExports if_hdl avails
171 = hPutStr if_hdl "_exports_\n" >>
172 hPutCol if_hdl do_one_module (fmToList export_fm)
174 -- Sort them into groups by module
175 export_fm :: FiniteMap Module [AvailInfo]
176 export_fm = foldr insert emptyFM avails
178 insert NotAvailable efm = efm
179 insert avail efm = addToFM_C (++) efm mod [avail]
181 mod = nameModule (availName avail)
183 -- Print one module's worth of stuff
184 do_one_module (mod_name, avails@(avail1:_))
185 = hsep [pp_hif (ifaceFlavour (availName avail1)),
187 hsep (map upp_avail (sortLt lt_avail avails))
190 -- The "!" indicates that the exported things came from a hi-boot interface
191 pp_hif HiFile = empty
192 pp_hif HiBootFile = char '!'
194 ifaceFixities if_hdl [] = return ()
195 ifaceFixities if_hdl fixities
196 = hPutStr if_hdl "_fixities_\n" >>
197 hPutCol if_hdl upp_fixity fixities
200 %************************************************************************
202 \subsection{Instance declarations}
204 %************************************************************************
208 ifaceInstances :: Handle -> Bag InstInfo -> IO IdSet -- The IdSet is the needed dfuns
209 ifaceInstances if_hdl inst_infos
210 | null togo_insts = return emptyIdSet
211 | otherwise = hPutStr if_hdl "_instances_\n" >>
212 hPutCol if_hdl pp_inst (sortLt lt_inst togo_insts) >>
215 togo_insts = filter is_togo_inst (bagToList inst_infos)
216 needed_ids = mkIdSet [dfun_id | InstInfo _ _ _ _ _ dfun_id _ _ _ <- togo_insts]
217 is_togo_inst (InstInfo _ _ _ _ _ dfun_id _ _ _) = isLocallyDefined dfun_id
220 lt_inst (InstInfo _ _ _ _ _ dfun_id1 _ _ _)
221 (InstInfo _ _ _ _ _ dfun_id2 _ _ _)
222 = getOccName dfun_id1 < getOccName dfun_id2
223 -- The dfuns are assigned names df1, df2, etc, in order of original textual
224 -- occurrence, and this makes as good a sort order as any
227 pp_inst (InstInfo clas tvs tys theta _ dfun_id _ _ _)
229 forall_ty = mkSigmaTy tvs theta (mkDictTy clas tys)
230 renumbered_ty = nmbrGlobalType forall_ty
232 hcat [ptext SLIT("instance "), pprType renumbered_ty,
233 ptext SLIT(" = "), ppr_unqual_name dfun_id, semi]
237 %************************************************************************
239 \subsection{Printing values}
241 %************************************************************************
244 ifaceId :: (Id -> IdInfo) -- This function "knows" the extra info added
245 -- by the STG passes. Sigh
247 -> IdSet -- Set of Ids that are needed by earlier interface
248 -- file emissions. If the Id isn't in this set, and isn't
249 -- exported, there's no need to emit anything
250 -> Bool -- True <=> recursive, so don't print unfolding
252 -> CoreExpr -- The Id's right hand side
253 -> Maybe (SDoc, IdSet) -- The emitted stuff, plus a possibly-augmented set of needed Ids
255 ifaceId get_idinfo needed_ids is_rec id rhs
256 | not (id `elementOfIdSet` needed_ids || -- Needed [no id in needed_ids has omitIfaceSigForId]
257 (isExported id && not (omitIfaceSigForId id))) -- or exported and not to be omitted
258 = Nothing -- Well, that was easy!
260 ifaceId get_idinfo needed_ids is_rec id rhs
261 = Just (hsep [sig_pretty, pp_double_semi, prag_pretty], new_needed_ids)
263 pp_double_semi = ptext SLIT(";;")
264 idinfo = get_idinfo id
265 inline_pragma = getInlinePragma id
267 ty_pretty = pprType (nmbrGlobalType (idType id))
268 sig_pretty = hcat [ppr (getOccName id), ptext SLIT(" _:_ "), ty_pretty]
271 | opt_OmitInterfacePragmas = empty
272 | otherwise = hsep [arity_pretty, strict_pretty, unfold_pretty, pp_double_semi]
274 ------------ Arity --------------
275 arity_pretty = ppArityInfo (arityInfo idinfo)
277 ------------ Strictness --------------
278 strict_info = strictnessInfo idinfo
279 has_worker = workerExists strict_info
280 strict_pretty = ppStrictnessInfo strict_info <+> wrkr_pretty
282 wrkr_pretty | not has_worker = empty
283 | null con_list = pprId work_id
284 | otherwise = pprId work_id <+>
285 braces (hsep (map (pprId) con_list))
287 (work_id, wrapper_cons) = getWorkerIdAndCons id rhs
288 con_list = idSetToList wrapper_cons
290 ------------ Unfolding --------------
291 unfold_pretty | show_unfold = hsep [ptext unfold_herald, pprIfaceUnfolding rhs]
294 unfold_herald = case inline_pragma of
295 IMustBeINLINEd -> SLIT("_U_")
296 IWantToBeINLINEd -> SLIT("_U_")
299 show_unfold = not implicit_unfolding && -- Not unnecessary
300 not dodgy_unfolding -- Not dangerous
302 implicit_unfolding = has_worker ||
303 bottomIsGuaranteed strict_info
305 dodgy_unfolding = case guidance of -- True <=> too big to show, or the Inline pragma
306 UnfoldNever -> True -- says it shouldn't be inlined
309 guidance = calcUnfoldingGuidance inline_pragma
310 opt_InterfaceUnfoldThreshold
314 ------------ Extra free Ids --------------
315 new_needed_ids = (needed_ids `minusIdSet` unitIdSet id) `unionIdSets`
318 extra_ids | opt_OmitInterfacePragmas = emptyIdSet
319 | otherwise = worker_ids `unionIdSets`
322 worker_ids | has_worker = unitIdSet work_id
323 | otherwise = emptyIdSet
325 unfold_ids | show_unfold = free_vars
326 | otherwise = emptyIdSet
328 (_,free_vars) = addExprFVs interesting emptyIdSet rhs
329 interesting bound id = isLocallyDefined id &&
330 not (id `elementOfIdSet` bound) &&
331 not (omitIfaceSigForId id)
336 -> IdSet -- These Ids are needed already
337 -> [Id] -- Ids used at code-gen time; they have better pragma info!
338 -> [CoreBinding] -- In dependency order, later depend on earlier
341 ifaceBinds hdl needed_ids final_ids binds
342 = mapIO (printForIface hdl) pretties >>
345 final_id_map = listToUFM [(id,id) | id <- final_ids]
346 get_idinfo id = case lookupUFM final_id_map id of
347 Just id' -> getIdInfo id'
348 Nothing -> pprTrace "ifaceBinds not found:" (ppr id) $
351 pretties = go needed_ids (reverse binds) -- Reverse so that later things will
352 -- provoke earlier ones to be emitted
353 go needed [] = if not (isEmptyIdSet needed) then
354 pprTrace "ifaceBinds: free vars:"
355 (sep (map ppr (idSetToList needed))) $
360 go needed (NonRec id rhs : binds)
361 = case ifaceId get_idinfo needed False id rhs of
362 Nothing -> go needed binds
363 Just (pretty, needed') -> pretty : go needed' binds
365 -- Recursive groups are a bit more of a pain. We may only need one to
366 -- start with, but it may call out the next one, and so on. So we
367 -- have to look for a fixed point.
368 go needed (Rec pairs : binds)
369 = pretties ++ go needed'' binds
371 (needed', pretties) = go_rec needed pairs
372 needed'' = needed' `minusIdSet` mkIdSet (map fst pairs)
373 -- Later ones may spuriously cause earlier ones to be "needed" again
375 go_rec :: IdSet -> [(Id,CoreExpr)] -> (IdSet, [SDoc])
377 | null pretties = (needed, [])
378 | otherwise = (final_needed, more_pretties ++ pretties)
380 reduced_pairs = [pair | (pair,Nothing) <- pairs `zip` maybes]
381 pretties = catMaybes maybes
382 (needed', maybes) = mapAccumL do_one needed pairs
383 (final_needed, more_pretties) = go_rec needed' reduced_pairs
385 do_one needed (id,rhs) = case ifaceId get_idinfo needed True id rhs of
386 Nothing -> (needed, Nothing)
387 Just (pretty, needed') -> (needed', Just pretty)
391 %************************************************************************
393 \subsection{Random small things}
395 %************************************************************************
398 ifaceTyCons hdl tycons = hPutCol hdl upp_tycon (sortLt (<) (filter (for_iface_name . getName) tycons ))
399 ifaceClasses hdl classes = hPutCol hdl upp_class (sortLt (<) (filter (for_iface_name . getName) classes))
401 for_iface_name name = isLocallyDefined name &&
402 not (isWiredInName name)
404 upp_tycon tycon = ifaceTyCon tycon
405 upp_class clas = ifaceClass clas
410 ifaceTyCon :: TyCon -> SDoc
413 = hsep [ ptext SLIT("type"),
415 pprTyVarBndrs tyvars,
421 (tyvars, ty) = getSynTyConDefn tycon
425 = hsep [ ptext keyword,
426 ppr_decl_context (tyConTheta tycon),
428 pprTyVarBndrs (tyConTyVars tycon),
430 hsep (punctuate (ptext SLIT(" | ")) (map ppr_con (tyConDataCons tycon))),
434 keyword | isNewTyCon tycon = SLIT("newtype")
435 | otherwise = SLIT("data")
440 hsep (map ppr_arg_ty (strict_marks `zip` arg_tys))
445 braces $ hsep $ punctuate comma (map ppr_field (strict_marks `zip` field_labels))
448 field_labels = dataConFieldLabels data_con
449 arg_tys = dataConRawArgTys data_con
450 strict_marks = dataConStrictMarks data_con
451 name = getName data_con
453 ppr_arg_ty (strict_mark, ty) = ppr_strict_mark strict_mark <> pprParendType ty
455 ppr_strict_mark NotMarkedStrict = empty
456 ppr_strict_mark MarkedStrict = ptext SLIT("! ")
457 -- The extra space helps the lexical analyser that lexes
458 -- interface files; it doesn't make the rigid operator/identifier
459 -- distinction, so "!a" is a valid identifier so far as it is concerned
461 ppr_field (strict_mark, field_label)
462 = hsep [ ppr (fieldLabelName field_label),
464 ppr_strict_mark strict_mark <> pprParendType (fieldLabelType field_label)
468 = pprPanic "pprIfaceTyDecl" (ppr tycon)
471 = hsep [ptext SLIT("class"),
472 ppr_decl_context sc_theta,
473 ppr clas, -- Print the name
474 pprTyVarBndrs clas_tyvars,
479 (clas_tyvars, sc_theta, _, sel_ids, defms) = classBigSig clas
481 pp_ops | null sel_ids = empty
482 | otherwise = hsep [ptext SLIT("where"),
483 braces (hsep (punctuate semi (zipWith ppr_classop sel_ids defms)))
486 ppr_classop sel_id maybe_defm
487 = ASSERT( sel_tyvars == clas_tyvars)
488 hsep [ppr (getOccName sel_id),
489 if maybeToBool maybe_defm then equals else empty,
494 (sel_tyvars, _, op_ty) = splitSigmaTy (idType sel_id)
496 ppr_decl_context :: ThetaType -> SDoc
497 ppr_decl_context [] = empty
498 ppr_decl_context theta
499 = braces (hsep (punctuate comma (map (ppr_dict) theta)))
503 ppr_dict (clas,tys) = ppr clas <+> hsep (map pprParendType tys)
506 %************************************************************************
508 \subsection{Random small things}
510 %************************************************************************
512 When printing export lists, we print like this:
514 AvailTC C [C, x, y] C(x,y)
515 AvailTC C [x, y] C!(x,y) -- Exporting x, y but not C
518 upp_avail NotAvailable = empty
519 upp_avail (Avail name) = upp_occname (getOccName name)
520 upp_avail (AvailTC name []) = empty
521 upp_avail (AvailTC name ns) = hcat [upp_occname (getOccName name), bang, upp_export ns']
523 bang | name `elem` ns = empty
524 | otherwise = char '|'
525 ns' = filter (/= name) ns
527 upp_export [] = empty
528 upp_export names = parens (hsep (map (upp_occname . getOccName) names))
530 upp_fixity (occ, fixity) = hcat [ppr fixity, space, upp_occname occ, semi]
532 ppr_unqual_name :: NamedThing a => a -> SDoc -- Just its occurrence name
533 ppr_unqual_name name = upp_occname (getOccName name)
535 upp_occname :: OccName -> SDoc
536 upp_occname occ = ptext (occNameString occ)
540 %************************************************************************
542 \subsection{Comparisons
544 %************************************************************************
547 The various sorts above simply prevent unnecessary "wobbling" when
548 things change that don't have to. We therefore compare lexically, not
552 lt_avail :: AvailInfo -> AvailInfo -> Bool
554 a1 `lt_avail` a2 = availName a1 `lt_name` availName a2
556 lt_name :: Name -> Name -> Bool
557 n1 `lt_name` n2 = modAndOcc n1 < modAndOcc n2
559 lt_lexical :: NamedThing a => a -> a -> Bool
560 lt_lexical a1 a2 = getName a1 `lt_name` getName a2
562 lt_imp_vers :: ImportVersion a -> ImportVersion a -> Bool
563 lt_imp_vers (m1,_,_,_) (m2,_,_,_) = m1 < m2
565 sort_versions vs = sortLt lt_vers vs
567 lt_vers :: LocalVersion Name -> LocalVersion Name -> Bool
568 lt_vers (n1,v1) (n2,v2) = n1 `lt_name` n2
577 hPutCol hdl fmt xs = mapIO (printForIface hdl . fmt) xs
579 mapIO :: (a -> IO b) -> [a] -> IO ()
580 mapIO f [] = return ()
581 mapIO f (x:xs) = f x >> mapIO f xs