2 % (c) The GRASP/AQUA Project, Glasgow University, 1993-1998
4 \section[MkIface]{Print an interface for a module}
8 startIface, endIface, ifaceDecls
11 #include "HsVersions.h"
13 import IO ( Handle, hPutStr, openFile,
14 hClose, hPutStrLn, IOMode(..) )
17 import BasicTypes ( Fixity(..), FixityDirection(..), NewOrData(..) )
19 import RnEnv ( availName )
21 import TcInstUtil ( InstInfo(..) )
24 import Id ( Id, idType, idInfo, omitIfaceSigForId, isUserExportedId,
29 import DataCon ( StrictnessMark(..), dataConSig, dataConFieldLabels, dataConStrictMarks )
30 import IdInfo ( IdInfo, StrictnessInfo(..), ArityInfo, InlinePragInfo(..), inlinePragInfo,
31 arityInfo, ppArityInfo, arityLowerBound,
32 strictnessInfo, ppStrictnessInfo, isBottomingStrictness,
33 cafInfo, ppCafInfo, specInfo,
35 workerExists, workerInfo, ppWorkerInfo
37 import CoreSyn ( CoreExpr, CoreBind, Bind(..), rulesRules, rulesRhsFreeVars )
38 import CoreFVs ( exprSomeFreeVars, ruleSomeLhsFreeVars, ruleSomeFreeVars )
39 import CoreUnfold ( calcUnfoldingGuidance, okToUnfoldInHiFile, couldBeSmallEnoughToInline )
40 import Module ( moduleString, pprModule, pprModuleName )
41 import Name ( isLocallyDefined, isWiredInName, nameRdrName, nameModule,
44 import OccName ( OccName, pprOccName )
45 import TyCon ( TyCon, getSynTyConDefn, isSynTyCon, isNewTyCon, isAlgTyCon,
46 tyConTheta, tyConTyVars, tyConDataCons
48 import Class ( Class, classBigSig )
49 import FieldLabel ( fieldLabelName, fieldLabelType )
50 import Type ( mkSigmaTy, splitSigmaTy, mkDictTy, tidyTopType, deNoteType,
55 import PprCore ( pprIfaceUnfolding, pprCoreRule )
56 import Rules ( pprProtoCoreRule, ProtoCoreRule(..) )
58 import Bag ( bagToList, isEmptyBag )
59 import Maybes ( catMaybes, maybeToBool )
60 import FiniteMap ( emptyFM, addToFM, addToFM_C, fmToList, FiniteMap )
61 import UniqFM ( lookupUFM, listToUFM )
62 import UniqSet ( uniqSetToList )
63 import Util ( sortLt, mapAccumL )
68 We have a function @startIface@ to open the output file and put
69 (something like) ``interface Foo'' in it. It gives back a handle
70 for subsequent additions to the interface file.
72 We then have one-function-per-block-of-interface-stuff, e.g.,
73 @ifaceExportList@ produces the @__exports__@ section; it appends
74 to the handle provided by @startIface@.
77 startIface :: Module -> InterfaceDetails
78 -> IO (Maybe Handle) -- Nothing <=> don't do an interface
80 ifaceDecls :: Maybe Handle
83 -> [Id] -- Ids used at code-gen time; they have better pragma info!
84 -> [CoreBind] -- In dependency order, later depend on earlier
85 -> [ProtoCoreRule] -- Rules
88 endIface :: Maybe Handle -> IO ()
92 startIface mod (has_orphans, import_usages, ExportEnv avails fixities)
93 = case opt_ProduceHi of
94 Nothing -> return Nothing ; -- not producing any .hi file
97 if_hdl <- openFile fn WriteMode
98 hPutStr if_hdl ("__interface " ++ moduleString mod)
99 hPutStr if_hdl (' ' : show (opt_HiVersion :: Int) ++ orphan_indicator)
100 hPutStrLn if_hdl " where"
101 ifaceExports if_hdl avails
102 ifaceImports if_hdl import_usages
103 ifaceFixities if_hdl fixities
106 orphan_indicator | has_orphans = " !"
109 endIface Nothing = return ()
110 endIface (Just if_hdl) = hPutStr if_hdl "\n" >> hClose if_hdl
115 ifaceDecls Nothing tycons classes inst_info final_ids simplified rules = return ()
116 ifaceDecls (Just hdl)
120 orphan_rules -- Rules defined locally for an Id that is *not* defined locally
121 | null_decls = return ()
122 -- You could have a module with just (re-)exports/instances in it
124 = ifaceClasses hdl classes >>
125 ifaceInstances hdl inst_infos >>= \ inst_ids ->
126 ifaceTyCons hdl tycons >>
127 ifaceBinds hdl (inst_ids `unionVarSet` orphan_rule_ids)
128 final_ids binds >>= \ emitted_ids ->
129 ifaceRules hdl orphan_rules emitted_ids >>
132 orphan_rule_ids = unionVarSets [ ruleSomeFreeVars interestingId rule
133 | ProtoCoreRule _ _ rule <- orphan_rules]
135 null_decls = null binds &&
138 isEmptyBag inst_infos &&
143 ifaceImports if_hdl import_usages
144 = hPutCol if_hdl upp_uses (sortLt lt_imp_vers import_usages)
146 upp_uses (m, mv, has_orphans, whats_imported)
147 = hsep [ptext SLIT("import"), pprModuleName m,
149 upp_import_versions whats_imported
152 pp_orphan | has_orphans = ptext SLIT("!")
155 -- Importing the whole module is indicated by an empty list
156 upp_import_versions Everything = empty
158 -- For imported versions we do print the version number
159 upp_import_versions (Specifically nvs)
160 = dcolon <+> hsep [ hsep [ppr_unqual_name n, int v] | (n,v) <- sort_versions nvs ]
162 ifaceModuleDeps if_hdl [] = return ()
163 ifaceModuleDeps if_hdl mod_deps
165 lines = map ppr_mod_dep mod_deps
166 ppr_mod_dep (mod, contains_orphans)
167 | contains_orphans = pprModuleName mod <+> ptext SLIT("!")
168 | otherwise = pprModuleName mod
170 printForIface if_hdl (ptext SLIT("__depends") <+> vcat lines <> ptext SLIT(" ;")) >>
173 ifaceExports if_hdl [] = return ()
174 ifaceExports if_hdl avails
175 = hPutCol if_hdl do_one_module (fmToList export_fm)
177 -- Sort them into groups by module
178 export_fm :: FiniteMap Module [AvailInfo]
179 export_fm = foldr insert emptyFM avails
181 insert avail efm = addToFM_C (++) efm mod [avail]
183 mod = nameModule (availName avail)
185 -- Print one module's worth of stuff
186 do_one_module :: (Module, [AvailInfo]) -> SDoc
187 do_one_module (mod_name, avails@(avail1:_))
188 = ptext SLIT("__export ") <>
189 hsep [pprModule mod_name,
190 hsep (map upp_avail (sortLt lt_avail avails))
193 ifaceFixities if_hdl [] = return ()
194 ifaceFixities if_hdl fixities
195 = hPutCol if_hdl upp_fixity fixities
197 ifaceRules if_hdl rules emitted
198 | null orphan_rule_pretties && null local_id_pretties
201 = do printForIface if_hdl (vcat [
202 ptext SLIT("{-## __R"),
204 vcat orphan_rule_pretties,
206 vcat local_id_pretties,
213 orphan_rule_pretties = [ pprCoreRule (Just fn) rule <+> semi
214 | ProtoCoreRule _ fn rule <- rules
216 local_id_pretties = [ pprCoreRule (Just fn) rule <+> semi
217 | fn <- varSetElems emitted,
218 rule <- rulesRules (getIdSpecialisation fn),
219 all (`elemVarSet` emitted) (varSetElems (ruleSomeLhsFreeVars interestingId rule))
220 -- Spit out a rule only if all its lhs free vars are eemitted
224 %************************************************************************
226 \subsection{Instance declarations}
228 %************************************************************************
232 ifaceInstances :: Handle -> Bag InstInfo -> IO IdSet -- The IdSet is the needed dfuns
233 ifaceInstances if_hdl inst_infos
234 | null togo_insts = return emptyVarSet
235 | otherwise = hPutCol if_hdl pp_inst (sortLt lt_inst togo_insts) >>
238 togo_insts = filter is_togo_inst (bagToList inst_infos)
239 needed_ids = mkVarSet [dfun_id | InstInfo _ _ _ _ dfun_id _ _ _ <- togo_insts]
240 is_togo_inst (InstInfo _ _ _ _ dfun_id _ _ _) = isLocallyDefined dfun_id
243 lt_inst (InstInfo _ _ _ _ dfun_id1 _ _ _)
244 (InstInfo _ _ _ _ dfun_id2 _ _ _)
245 = getOccName dfun_id1 < getOccName dfun_id2
246 -- The dfuns are assigned names df1, df2, etc, in order of original textual
247 -- occurrence, and this makes as good a sort order as any
250 pp_inst (InstInfo clas tvs tys theta dfun_id _ _ _)
252 -- The deNoteType is very important. It removes all type
253 -- synonyms from the instance type in interface files.
254 -- That in turn makes sure that when reading in instance decls
255 -- from interface files that the 'gating' mechanism works properly.
256 -- Otherwise you could have
257 -- type Tibble = T Int
258 -- instance Foo Tibble where ...
259 -- and this instance decl wouldn't get imported into a module
260 -- that mentioned T but not Tibble.
261 forall_ty = mkSigmaTy tvs theta (deNoteType (mkDictTy clas tys))
262 renumbered_ty = tidyTopType forall_ty
264 hcat [ptext SLIT("instance "), pprType renumbered_ty,
265 ptext SLIT(" = "), ppr_unqual_name dfun_id, semi]
269 %************************************************************************
271 \subsection{Printing values}
273 %************************************************************************
276 ifaceId :: (Id -> IdInfo) -- This function "knows" the extra info added
277 -- by the STG passes. Sigh
279 -> IdSet -- Set of Ids that are needed by earlier interface
280 -- file emissions. If the Id isn't in this set, and isn't
281 -- exported, there's no need to emit anything
282 -> Bool -- True <=> recursive, so don't print unfolding
284 -> CoreExpr -- The Id's right hand side
285 -> Maybe (SDoc, IdSet) -- The emitted stuff, plus any *extra* needed Ids
287 ifaceId get_idinfo needed_ids is_rec id rhs
288 | not (id `elemVarSet` needed_ids || -- Needed [no id in needed_ids has omitIfaceSigForId]
289 (isUserExportedId id && not (omitIfaceSigForId id))) -- or exported and not to be omitted
290 = Nothing -- Well, that was easy!
292 ifaceId get_idinfo needed_ids is_rec id rhs
293 = ASSERT2( arity_matches_strictness, ppr id )
294 Just (hsep [sig_pretty, prag_pretty, char ';'], new_needed_ids)
296 core_idinfo = idInfo id
297 stg_idinfo = get_idinfo id
299 ty_pretty = pprType (idType id)
300 sig_pretty = hsep [ppr (getOccName id), dcolon, ty_pretty]
303 | opt_OmitInterfacePragmas = empty
304 | otherwise = hsep [ptext SLIT("{-##"),
313 ------------ Arity --------------
314 arity_info = arityInfo stg_idinfo
315 arity_pretty = ppArityInfo arity_info
317 ------------ Caf Info --------------
318 caf_pretty = ppCafInfo (cafInfo stg_idinfo)
320 ------------ CPR Info --------------
321 cpr_pretty = ppCprInfo (cprInfo core_idinfo)
323 ------------ Strictness --------------
324 strict_info = strictnessInfo core_idinfo
325 bottoming_fn = isBottomingStrictness strict_info
326 strict_pretty = ppStrictnessInfo strict_info
328 ------------ Worker --------------
329 work_info = workerInfo core_idinfo
330 has_worker = workerExists work_info
331 wrkr_pretty = ppWorkerInfo work_info
332 Just work_id = work_info
335 ------------ Unfolding --------------
336 inline_pragma = inlinePragInfo core_idinfo
337 dont_inline = case inline_pragma of
338 IMustNotBeINLINEd -> True
339 IAmALoopBreaker -> True
342 unfold_pretty | show_unfold = ptext SLIT("__U") <+> pprIfaceUnfolding rhs
345 show_unfold = not has_worker && -- Not unnecessary
346 not bottoming_fn && -- Not necessary
348 rhs_is_small && -- Small enough
349 okToUnfoldInHiFile rhs -- No casms etc
351 rhs_is_small = couldBeSmallEnoughToInline (calcUnfoldingGuidance opt_UF_HiFileThreshold rhs)
353 ------------ Specialisations --------------
354 spec_info = specInfo core_idinfo
356 ------------ Extra free Ids --------------
357 new_needed_ids | opt_OmitInterfacePragmas = emptyVarSet
358 | otherwise = worker_ids `unionVarSet`
359 unfold_ids `unionVarSet`
362 worker_ids | has_worker && interestingId work_id = unitVarSet work_id
363 -- Conceivably, the worker might come from
365 | otherwise = emptyVarSet
367 spec_ids = filterVarSet interestingId (rulesRhsFreeVars spec_info)
369 unfold_ids | show_unfold = find_fvs rhs
370 | otherwise = emptyVarSet
372 find_fvs expr = exprSomeFreeVars interestingId expr
374 ------------ Sanity checking --------------
375 -- The arity of a wrapper function should match its strictness,
376 -- or else an importing module will get very confused indeed.
377 arity_matches_strictness
380 StrictnessInfo ds _ -> length ds == arityLowerBound arity_info
383 interestingId id = isId id && isLocallyDefined id &&
384 not (omitIfaceSigForId id)
389 -> IdSet -- These Ids are needed already
390 -> [Id] -- Ids used at code-gen time; they have better pragma info!
391 -> [CoreBind] -- In dependency order, later depend on earlier
392 -> IO IdSet -- Set of Ids actually spat out
394 ifaceBinds hdl needed_ids final_ids binds
395 = mapIO (printForIface hdl) (bagToList pretties) >>
399 final_id_map = listToUFM [(id,id) | id <- final_ids]
400 get_idinfo id = case lookupUFM final_id_map id of
401 Just id' -> idInfo id'
402 Nothing -> pprTrace "ifaceBinds not found:" (ppr id) $
405 (pretties, emitted) = go needed_ids (reverse binds) emptyBag emptyVarSet
406 -- Reverse so that later things will
407 -- provoke earlier ones to be emitted
408 go needed [] pretties emitted
409 | not (isEmptyVarSet needed) = pprTrace "ifaceBinds: free vars:"
410 (sep (map ppr (varSetElems needed)))
412 | otherwise = (pretties, emitted)
414 go needed (NonRec id rhs : binds) pretties emitted
415 = case ifaceId get_idinfo needed False id rhs of
416 Nothing -> go needed binds pretties emitted
417 Just (pretty, extras) -> let
418 needed' = (needed `unionVarSet` extras) `delVarSet` id
419 -- 'extras' can include the Id itself via a rule
420 emitted' = emitted `extendVarSet` id
422 go needed' binds (pretty `consBag` pretties) emitted'
424 -- Recursive groups are a bit more of a pain. We may only need one to
425 -- start with, but it may call out the next one, and so on. So we
426 -- have to look for a fixed point.
427 go needed (Rec pairs : binds) pretties emitted
428 = go needed' binds pretties' emitted'
430 (new_pretties, new_emitted, extras) = go_rec needed pairs
431 pretties' = new_pretties `unionBags` pretties
432 needed' = (needed `unionVarSet` extras) `minusVarSet` mkVarSet (map fst pairs)
433 emitted' = emitted `unionVarSet` new_emitted
435 go_rec :: IdSet -> [(Id,CoreExpr)] -> (Bag SDoc, IdSet, IdSet)
437 | null pretties = (emptyBag, emptyVarSet, emptyVarSet)
438 | otherwise = (more_pretties `unionBags` listToBag pretties,
439 more_emitted `unionVarSet` mkVarSet emitted,
440 more_extras `unionVarSet` extras)
442 maybes = map do_one pairs
443 emitted = [id | ((id,_), Just _) <- pairs `zip` maybes]
444 reduced_pairs = [pair | (pair, Nothing) <- pairs `zip` maybes]
445 (pretties, extras_s) = unzip (catMaybes maybes)
446 extras = unionVarSets extras_s
447 (more_pretties, more_emitted, more_extras) = go_rec extras reduced_pairs
449 do_one (id,rhs) = ifaceId get_idinfo needed True id rhs
453 %************************************************************************
455 \subsection{Random small things}
457 %************************************************************************
460 ifaceTyCons hdl tycons = hPutCol hdl upp_tycon (sortLt (<) (filter (for_iface_name . getName) tycons ))
461 ifaceClasses hdl classes = hPutCol hdl upp_class (sortLt (<) (filter (for_iface_name . getName) classes))
463 for_iface_name name = isLocallyDefined name &&
464 not (isWiredInName name)
466 upp_tycon tycon = ifaceTyCon tycon
467 upp_class clas = ifaceClass clas
472 ifaceTyCon :: TyCon -> SDoc
475 = hsep [ ptext SLIT("type"),
477 pprTyVarBndrs tyvars,
483 (tyvars, ty) = getSynTyConDefn tycon
487 = hsep [ ptext keyword,
488 ppr_decl_context (tyConTheta tycon),
490 pprTyVarBndrs (tyConTyVars tycon),
492 hsep (punctuate (ptext SLIT(" | ")) (map ppr_con (tyConDataCons tycon))),
496 keyword | isNewTyCon tycon = SLIT("newtype")
497 | otherwise = SLIT("data")
499 tyvars = tyConTyVars tycon
503 = ASSERT( tycon == tycon1 && tyvars == tyvars1 )
504 hsep [ ppr_ex ex_tyvars ex_theta,
506 hsep (map ppr_arg_ty (strict_marks `zip` arg_tys))
510 = hsep [ ppr_ex ex_tyvars ex_theta,
512 braces $ hsep $ punctuate comma (map ppr_field (strict_marks `zip` field_labels))
515 (tyvars1, theta1, ex_tyvars, ex_theta, arg_tys, tycon1) = dataConSig data_con
516 field_labels = dataConFieldLabels data_con
517 strict_marks = dataConStrictMarks data_con
518 name = getName data_con
520 ppr_ex [] ex_theta = ASSERT( null ex_theta ) empty
521 ppr_ex ex_tvs ex_theta = ptext SLIT("__forall") <+> brackets (pprTyVarBndrs ex_tvs)
522 <+> pprIfaceTheta ex_theta <+> ptext SLIT("=>")
524 ppr_arg_ty (strict_mark, ty) = ppr_strict_mark strict_mark <> pprParendType ty
526 ppr_strict_mark NotMarkedStrict = empty
527 ppr_strict_mark (MarkedUnboxed _ _) = ptext SLIT("! ! ")
528 ppr_strict_mark MarkedStrict = ptext SLIT("! ")
530 ppr_field (strict_mark, field_label)
531 = hsep [ ppr (fieldLabelName field_label),
533 ppr_strict_mark strict_mark <> pprParendType (fieldLabelType field_label)
537 = pprPanic "pprIfaceTyDecl" (ppr tycon)
540 = hsep [ptext SLIT("class"),
541 ppr_decl_context sc_theta,
542 ppr clas, -- Print the name
543 pprTyVarBndrs clas_tyvars,
548 (clas_tyvars, sc_theta, _, sel_ids, defms) = classBigSig clas
550 pp_ops | null sel_ids = empty
551 | otherwise = hsep [ptext SLIT("where"),
552 braces (hsep (punctuate semi (zipWith ppr_classop sel_ids defms)))
555 ppr_classop sel_id maybe_defm
556 = ASSERT( sel_tyvars == clas_tyvars)
557 hsep [ppr (getOccName sel_id),
558 if maybeToBool maybe_defm then equals else empty,
563 (sel_tyvars, _, op_ty) = splitSigmaTy (idType sel_id)
565 ppr_decl_context :: ThetaType -> SDoc
566 ppr_decl_context [] = empty
567 ppr_decl_context theta = pprIfaceTheta theta <+> ptext SLIT(" =>")
569 pprIfaceTheta :: ThetaType -> SDoc -- Use braces rather than parens in interface files
570 pprIfaceTheta [] = empty
571 pprIfaceTheta theta = braces (hsep (punctuate comma [pprConstraint c tys | (c,tys) <- theta]))
574 %************************************************************************
576 \subsection{Random small things}
578 %************************************************************************
580 When printing export lists, we print like this:
582 AvailTC C [C, x, y] C(x,y)
583 AvailTC C [x, y] C!(x,y) -- Exporting x, y but not C
586 upp_avail :: AvailInfo -> SDoc
587 upp_avail (Avail name) = pprOccName (getOccName name)
588 upp_avail (AvailTC name []) = empty
589 upp_avail (AvailTC name ns) = hcat [pprOccName (getOccName name), bang, upp_export ns']
591 bang | name `elem` ns = empty
592 | otherwise = char '|'
593 ns' = filter (/= name) ns
595 upp_export :: [Name] -> SDoc
596 upp_export [] = empty
597 upp_export names = braces (hsep (map (pprOccName . getOccName) names))
599 upp_fixity :: (Name, Fixity) -> SDoc
600 upp_fixity (name, fixity) = hsep [ptext SLIT("0"), ppr fixity, ppr name, semi]
601 -- Dummy version number!
603 ppr_unqual_name :: NamedThing a => a -> SDoc -- Just its occurrence name
604 ppr_unqual_name name = pprOccName (getOccName name)
608 %************************************************************************
610 \subsection{Comparisons}
612 %************************************************************************
615 The various sorts above simply prevent unnecessary "wobbling" when
616 things change that don't have to. We therefore compare lexically, not
620 lt_avail :: AvailInfo -> AvailInfo -> Bool
622 a1 `lt_avail` a2 = availName a1 `lt_name` availName a2
624 lt_name :: Name -> Name -> Bool
625 n1 `lt_name` n2 = nameRdrName n1 < nameRdrName n2
627 lt_lexical :: NamedThing a => a -> a -> Bool
628 lt_lexical a1 a2 = getName a1 `lt_name` getName a2
630 lt_imp_vers :: ImportVersion a -> ImportVersion a -> Bool
631 lt_imp_vers (m1,_,_,_) (m2,_,_,_) = m1 < m2
633 sort_versions vs = sortLt lt_vers vs
635 lt_vers :: LocalVersion Name -> LocalVersion Name -> Bool
636 lt_vers (n1,v1) (n2,v2) = n1 `lt_name` n2
645 hPutCol hdl fmt xs = mapIO (printForIface hdl . fmt) xs
647 mapIO :: (a -> IO b) -> [a] -> IO ()
648 mapIO f [] = return ()
649 mapIO f (x:xs) = f x >> mapIO f xs