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,
34 cprInfo, ppCprInfo, pprInlinePragInfo,
36 workerExists, workerInfo, ppWorkerInfo
38 import CoreSyn ( CoreExpr, CoreBind, Bind(..), rulesRules, rulesRhsFreeVars )
39 import CoreFVs ( exprSomeFreeVars, ruleSomeLhsFreeVars, ruleSomeFreeVars )
40 import CoreUnfold ( calcUnfoldingGuidance, okToUnfoldInHiFile, couldBeSmallEnoughToInline )
41 import Module ( moduleString, pprModule, pprModuleName )
42 import Name ( isLocallyDefined, isWiredInName, nameRdrName, nameModule,
45 import OccName ( OccName, pprOccName )
46 import TyCon ( TyCon, getSynTyConDefn, isSynTyCon, isNewTyCon, isAlgTyCon,
47 tyConTheta, tyConTyVars, tyConDataCons
49 import Class ( Class, classExtraBigSig )
50 import FieldLabel ( fieldLabelName, fieldLabelType )
51 import Type ( mkSigmaTy, splitSigmaTy, mkDictTy, tidyTopType,
52 deNoteType, classesToPreds,
57 import PprCore ( pprIfaceUnfolding, pprCoreRule )
58 import FunDeps ( pprFundeps )
59 import Rules ( pprProtoCoreRule, ProtoCoreRule(..) )
61 import Bag ( bagToList, isEmptyBag )
62 import Maybes ( catMaybes, maybeToBool )
63 import FiniteMap ( emptyFM, addToFM, addToFM_C, fmToList, FiniteMap )
64 import UniqFM ( lookupUFM, listToUFM )
65 import UniqSet ( uniqSetToList )
66 import Util ( sortLt, mapAccumL )
71 We have a function @startIface@ to open the output file and put
72 (something like) ``interface Foo'' in it. It gives back a handle
73 for subsequent additions to the interface file.
75 We then have one-function-per-block-of-interface-stuff, e.g.,
76 @ifaceExportList@ produces the @__exports__@ section; it appends
77 to the handle provided by @startIface@.
80 startIface :: Module -> InterfaceDetails
81 -> IO (Maybe Handle) -- Nothing <=> don't do an interface
83 ifaceDecls :: Maybe Handle
86 -> [Id] -- Ids used at code-gen time; they have better pragma info!
87 -> [CoreBind] -- In dependency order, later depend on earlier
88 -> [ProtoCoreRule] -- Rules
91 endIface :: Maybe Handle -> IO ()
95 startIface mod (has_orphans, import_usages, ExportEnv avails fixities _)
96 = case opt_ProduceHi of
97 Nothing -> return Nothing ; -- not producing any .hi file
100 if_hdl <- openFile fn WriteMode
101 hPutStr if_hdl ("__interface " ++ moduleString mod)
102 hPutStr if_hdl (' ' : show (opt_HiVersion :: Int) ++ orphan_indicator)
103 hPutStrLn if_hdl " where"
104 ifaceExports if_hdl avails
105 ifaceImports if_hdl import_usages
106 ifaceFixities if_hdl fixities
109 orphan_indicator | has_orphans = " !"
112 endIface Nothing = return ()
113 endIface (Just if_hdl) = hPutStr if_hdl "\n" >> hClose if_hdl
118 ifaceDecls Nothing tycons classes inst_info final_ids simplified rules = return ()
119 ifaceDecls (Just hdl)
123 orphan_rules -- Rules defined locally for an Id that is *not* defined locally
124 | null_decls = return ()
125 -- You could have a module with just (re-)exports/instances in it
127 = ifaceClasses hdl classes >>
128 ifaceInstances hdl inst_infos >>= \ inst_ids ->
129 ifaceTyCons hdl tycons >>
130 ifaceBinds hdl (inst_ids `unionVarSet` orphan_rule_ids)
131 final_ids binds >>= \ emitted_ids ->
132 ifaceRules hdl orphan_rules emitted_ids >>
135 orphan_rule_ids = unionVarSets [ ruleSomeFreeVars interestingId rule
136 | ProtoCoreRule _ _ rule <- orphan_rules]
138 null_decls = null binds &&
141 isEmptyBag inst_infos &&
146 ifaceImports if_hdl import_usages
147 = hPutCol if_hdl upp_uses (sortLt lt_imp_vers import_usages)
149 upp_uses (m, mv, has_orphans, whats_imported)
150 = hsep [ptext SLIT("import"), pprModuleName m,
152 upp_import_versions whats_imported
155 pp_orphan | has_orphans = ptext SLIT("!")
158 -- Importing the whole module is indicated by an empty list
159 upp_import_versions Everything = empty
161 -- For imported versions we do print the version number
162 upp_import_versions (Specifically nvs)
163 = dcolon <+> hsep [ hsep [ppr_unqual_name n, int v] | (n,v) <- sort_versions nvs ]
165 ifaceModuleDeps if_hdl [] = return ()
166 ifaceModuleDeps if_hdl mod_deps
168 lines = map ppr_mod_dep mod_deps
169 ppr_mod_dep (mod, contains_orphans)
170 | contains_orphans = pprModuleName mod <+> ptext SLIT("!")
171 | otherwise = pprModuleName mod
173 printForIface if_hdl (ptext SLIT("__depends") <+> vcat lines <> ptext SLIT(" ;")) >>
176 ifaceExports if_hdl [] = return ()
177 ifaceExports if_hdl avails
178 = hPutCol if_hdl do_one_module (fmToList export_fm)
180 -- Sort them into groups by module
181 export_fm :: FiniteMap Module [AvailInfo]
182 export_fm = foldr insert emptyFM avails
184 insert avail efm = addToFM_C (++) efm mod [avail]
186 mod = nameModule (availName avail)
188 -- Print one module's worth of stuff
189 do_one_module :: (Module, [AvailInfo]) -> SDoc
190 do_one_module (mod_name, avails@(avail1:_))
191 = ptext SLIT("__export ") <>
192 hsep [pprModule mod_name,
193 hsep (map upp_avail (sortLt lt_avail avails))
196 ifaceFixities if_hdl [] = return ()
197 ifaceFixities if_hdl fixities
198 = hPutCol if_hdl upp_fixity fixities
200 ifaceRules if_hdl rules emitted
201 | null orphan_rule_pretties && null local_id_pretties
204 = do printForIface if_hdl (vcat [
205 ptext SLIT("{-## __R"),
207 vcat orphan_rule_pretties,
209 vcat local_id_pretties,
216 orphan_rule_pretties = [ pprCoreRule (Just fn) rule
217 | ProtoCoreRule _ fn rule <- rules
219 local_id_pretties = [ pprCoreRule (Just fn) rule
220 | fn <- varSetElems emitted,
221 rule <- rulesRules (getIdSpecialisation fn),
222 all (`elemVarSet` emitted) (varSetElems (ruleSomeLhsFreeVars interestingId rule))
223 -- Spit out a rule only if all its lhs free vars are eemitted
227 %************************************************************************
229 \subsection{Instance declarations}
231 %************************************************************************
235 ifaceInstances :: Handle -> Bag InstInfo -> IO IdSet -- The IdSet is the needed dfuns
236 ifaceInstances if_hdl inst_infos
237 | null togo_insts = return emptyVarSet
238 | otherwise = hPutCol if_hdl pp_inst (sortLt lt_inst togo_insts) >>
241 togo_insts = filter is_togo_inst (bagToList inst_infos)
242 needed_ids = mkVarSet [dfun_id | InstInfo _ _ _ _ dfun_id _ _ _ <- togo_insts]
243 is_togo_inst (InstInfo _ _ _ _ dfun_id _ _ _) = isLocallyDefined dfun_id
246 lt_inst (InstInfo _ _ _ _ dfun_id1 _ _ _)
247 (InstInfo _ _ _ _ dfun_id2 _ _ _)
248 = getOccName dfun_id1 < getOccName dfun_id2
249 -- The dfuns are assigned names df1, df2, etc, in order of original textual
250 -- occurrence, and this makes as good a sort order as any
253 pp_inst (InstInfo clas tvs tys theta dfun_id _ _ _)
255 -- The deNoteType is very important. It removes all type
256 -- synonyms from the instance type in interface files.
257 -- That in turn makes sure that when reading in instance decls
258 -- from interface files that the 'gating' mechanism works properly.
259 -- Otherwise you could have
260 -- type Tibble = T Int
261 -- instance Foo Tibble where ...
262 -- and this instance decl wouldn't get imported into a module
263 -- that mentioned T but not Tibble.
264 forall_ty = mkSigmaTy tvs (classesToPreds theta)
265 (deNoteType (mkDictTy clas tys))
266 renumbered_ty = tidyTopType forall_ty
268 hcat [ptext SLIT("instance "), pprType renumbered_ty,
269 ptext SLIT(" = "), ppr_unqual_name dfun_id, semi]
273 %************************************************************************
275 \subsection{Printing values}
277 %************************************************************************
280 ifaceId :: (Id -> IdInfo) -- This function "knows" the extra info added
281 -- by the STG passes. Sigh
283 -> IdSet -- Set of Ids that are needed by earlier interface
284 -- file emissions. If the Id isn't in this set, and isn't
285 -- exported, there's no need to emit anything
286 -> Bool -- True <=> recursive, so don't print unfolding
288 -> CoreExpr -- The Id's right hand side
289 -> Maybe (SDoc, IdSet) -- The emitted stuff, plus any *extra* needed Ids
291 ifaceId get_idinfo needed_ids is_rec id rhs
292 | not (id `elemVarSet` needed_ids || -- Needed [no id in needed_ids has omitIfaceSigForId]
293 (isUserExportedId id && not (omitIfaceSigForId id))) -- or exported and not to be omitted
294 = Nothing -- Well, that was easy!
296 ifaceId get_idinfo needed_ids is_rec id rhs
297 = ASSERT2( arity_matches_strictness, ppr id )
298 Just (hsep [sig_pretty, prag_pretty, char ';'], new_needed_ids)
300 core_idinfo = idInfo id
301 stg_idinfo = get_idinfo id
303 ty_pretty = pprType (idType id)
304 sig_pretty = hsep [ppr (getOccName id), dcolon, ty_pretty]
307 | opt_OmitInterfacePragmas = empty
308 | otherwise = hsep [ptext SLIT("{-##"),
317 ------------ Arity --------------
318 arity_info = arityInfo stg_idinfo
319 arity_pretty = ppArityInfo arity_info
321 ------------ Caf Info --------------
322 caf_pretty = ppCafInfo (cafInfo stg_idinfo)
324 ------------ CPR Info --------------
325 cpr_pretty = ppCprInfo (cprInfo core_idinfo)
327 ------------ Strictness --------------
328 strict_info = strictnessInfo core_idinfo
329 bottoming_fn = isBottomingStrictness strict_info
330 strict_pretty = ppStrictnessInfo strict_info
332 ------------ Worker --------------
333 work_info = workerInfo core_idinfo
334 has_worker = workerExists work_info
335 wrkr_pretty = ppWorkerInfo work_info
336 Just work_id = work_info
339 ------------ Occ info --------------
340 loop_breaker = case occInfo core_idinfo of
341 IAmALoopBreaker -> True
344 ------------ Unfolding --------------
345 inline_pragma = inlinePragInfo core_idinfo
346 dont_inline = case inline_pragma of
347 IMustNotBeINLINEd False Nothing -> True -- Unconditional NOINLINE
351 unfold_pretty | show_unfold = ptext SLIT("__U") <> pprInlinePragInfo inline_pragma <+> pprIfaceUnfolding rhs
354 show_unfold = not has_worker && -- Not unnecessary
355 not bottoming_fn && -- Not necessary
358 rhs_is_small && -- Small enough
359 okToUnfoldInHiFile rhs -- No casms etc
361 rhs_is_small = couldBeSmallEnoughToInline (calcUnfoldingGuidance opt_UF_HiFileThreshold rhs)
363 ------------ Specialisations --------------
364 spec_info = specInfo core_idinfo
366 ------------ Extra free Ids --------------
367 new_needed_ids | opt_OmitInterfacePragmas = emptyVarSet
368 | otherwise = worker_ids `unionVarSet`
369 unfold_ids `unionVarSet`
372 worker_ids | has_worker && interestingId work_id = unitVarSet work_id
373 -- Conceivably, the worker might come from
375 | otherwise = emptyVarSet
377 spec_ids = filterVarSet interestingId (rulesRhsFreeVars spec_info)
379 unfold_ids | show_unfold = find_fvs rhs
380 | otherwise = emptyVarSet
382 find_fvs expr = exprSomeFreeVars interestingId expr
384 ------------ Sanity checking --------------
385 -- The arity of a wrapper function should match its strictness,
386 -- or else an importing module will get very confused indeed.
387 -- [later: actually all that is necessary is for strictness to exceed arity]
388 arity_matches_strictness
391 StrictnessInfo ds _ -> length ds >= arityLowerBound arity_info
394 interestingId id = isId id && isLocallyDefined id &&
395 not (omitIfaceSigForId id)
400 -> IdSet -- These Ids are needed already
401 -> [Id] -- Ids used at code-gen time; they have better pragma info!
402 -> [CoreBind] -- In dependency order, later depend on earlier
403 -> IO IdSet -- Set of Ids actually spat out
405 ifaceBinds hdl needed_ids final_ids binds
406 = mapIO (printForIface hdl) (bagToList pretties) >>
410 final_id_map = listToUFM [(id,id) | id <- final_ids]
411 get_idinfo id = case lookupUFM final_id_map id of
412 Just id' -> idInfo id'
413 Nothing -> pprTrace "ifaceBinds not found:" (ppr id) $
416 (pretties, emitted) = go needed_ids (reverse binds) emptyBag emptyVarSet
417 -- Reverse so that later things will
418 -- provoke earlier ones to be emitted
419 go needed [] pretties emitted
420 | not (isEmptyVarSet needed) = pprTrace "ifaceBinds: free vars:"
421 (sep (map ppr (varSetElems needed)))
423 | otherwise = (pretties, emitted)
425 go needed (NonRec id rhs : binds) pretties emitted
426 = case ifaceId get_idinfo needed False id rhs of
427 Nothing -> go needed binds pretties emitted
428 Just (pretty, extras) -> let
429 needed' = (needed `unionVarSet` extras) `delVarSet` id
430 -- 'extras' can include the Id itself via a rule
431 emitted' = emitted `extendVarSet` id
433 go needed' binds (pretty `consBag` pretties) emitted'
435 -- Recursive groups are a bit more of a pain. We may only need one to
436 -- start with, but it may call out the next one, and so on. So we
437 -- have to look for a fixed point.
438 go needed (Rec pairs : binds) pretties emitted
439 = go needed' binds pretties' emitted'
441 (new_pretties, new_emitted, extras) = go_rec needed pairs
442 pretties' = new_pretties `unionBags` pretties
443 needed' = (needed `unionVarSet` extras) `minusVarSet` mkVarSet (map fst pairs)
444 emitted' = emitted `unionVarSet` new_emitted
446 go_rec :: IdSet -> [(Id,CoreExpr)] -> (Bag SDoc, IdSet, IdSet)
448 | null pretties = (emptyBag, emptyVarSet, emptyVarSet)
449 | otherwise = (more_pretties `unionBags` listToBag pretties,
450 more_emitted `unionVarSet` mkVarSet emitted,
451 more_extras `unionVarSet` extras)
453 maybes = map do_one pairs
454 emitted = [id | ((id,_), Just _) <- pairs `zip` maybes]
455 reduced_pairs = [pair | (pair, Nothing) <- pairs `zip` maybes]
456 (pretties, extras_s) = unzip (catMaybes maybes)
457 extras = unionVarSets extras_s
458 (more_pretties, more_emitted, more_extras) = go_rec extras reduced_pairs
460 do_one (id,rhs) = ifaceId get_idinfo needed True id rhs
464 %************************************************************************
466 \subsection{Random small things}
468 %************************************************************************
471 ifaceTyCons hdl tycons = hPutCol hdl upp_tycon (sortLt (<) (filter (for_iface_name . getName) tycons))
472 ifaceClasses hdl classes = hPutCol hdl upp_class (sortLt (<) (filter (for_iface_name . getName) classes))
474 for_iface_name name = isLocallyDefined name &&
475 not (isWiredInName name)
477 upp_tycon tycon = ifaceTyCon tycon
478 upp_class clas = ifaceClass clas
483 ifaceTyCon :: TyCon -> SDoc
486 = hsep [ ptext SLIT("type"),
488 pprTyVarBndrs tyvars,
494 (tyvars, ty) = getSynTyConDefn tycon
498 = hsep [ ptext keyword,
499 ppr_decl_class_context (tyConTheta tycon),
501 pprTyVarBndrs (tyConTyVars tycon),
503 hsep (punctuate (ptext SLIT(" | ")) (map ppr_con (tyConDataCons tycon))),
507 keyword | isNewTyCon tycon = SLIT("newtype")
508 | otherwise = SLIT("data")
510 tyvars = tyConTyVars tycon
514 = ASSERT( tycon == tycon1 && tyvars == tyvars1 )
515 hsep [ ppr_ex ex_tyvars ex_theta,
517 hsep (map ppr_arg_ty (strict_marks `zip` arg_tys))
521 = hsep [ ppr_ex ex_tyvars ex_theta,
523 braces $ hsep $ punctuate comma (map ppr_field (strict_marks `zip` field_labels))
526 (tyvars1, theta1, ex_tyvars, ex_theta, arg_tys, tycon1) = dataConSig data_con
527 field_labels = dataConFieldLabels data_con
528 strict_marks = dataConStrictMarks data_con
529 name = getName data_con
531 ppr_ex [] ex_theta = ASSERT( null ex_theta ) empty
532 ppr_ex ex_tvs ex_theta = ptext SLIT("__forall") <+> brackets (pprTyVarBndrs ex_tvs)
533 <+> pprIfaceClasses ex_theta <+> ptext SLIT("=>")
535 ppr_arg_ty (strict_mark, ty) = ppr_strict_mark strict_mark <> pprParendType ty
537 ppr_strict_mark NotMarkedStrict = empty
538 ppr_strict_mark (MarkedUnboxed _ _) = ptext SLIT("! ! ")
539 ppr_strict_mark MarkedStrict = ptext SLIT("! ")
541 ppr_field (strict_mark, field_label)
542 = hsep [ ppr (fieldLabelName field_label),
544 ppr_strict_mark strict_mark <> pprParendType (fieldLabelType field_label)
548 = pprPanic "pprIfaceTyDecl" (ppr tycon)
551 = hsep [ptext SLIT("class"),
552 ppr_decl_class_context sc_theta,
553 ppr clas, -- Print the name
554 pprTyVarBndrs clas_tyvars,
560 (clas_tyvars, clas_fds, sc_theta, _, op_stuff) = classExtraBigSig clas
562 pp_ops | null op_stuff = empty
563 | otherwise = hsep [ptext SLIT("where"),
564 braces (hsep (punctuate semi (map ppr_classop op_stuff)))
567 ppr_classop (sel_id, dm_id, explicit_dm)
568 = ASSERT( sel_tyvars == clas_tyvars)
569 hsep [ppr (getOccName sel_id),
570 if explicit_dm then equals else empty,
575 (sel_tyvars, _, op_ty) = splitSigmaTy (idType sel_id)
577 ppr_decl_context :: ThetaType -> SDoc
578 ppr_decl_context [] = empty
579 ppr_decl_context theta = pprIfaceTheta theta <+> ptext SLIT(" =>")
581 ppr_decl_class_context :: [(Class,[Type])] -> SDoc
582 ppr_decl_class_context [] = empty
583 ppr_decl_class_context ctxt = pprIfaceClasses ctxt <+> ptext SLIT(" =>")
585 pprIfaceTheta :: ThetaType -> SDoc -- Use braces rather than parens in interface files
586 pprIfaceTheta [] = empty
587 pprIfaceTheta theta = braces (hsep (punctuate comma [pprPred p | p <- theta]))
589 pprIfaceClasses :: [(Class,[Type])] -> SDoc
590 pprIfaceClasses [] = empty
591 pprIfaceClasses theta = braces (hsep (punctuate comma [pprConstraint c tys | (c,tys) <- theta]))
594 %************************************************************************
596 \subsection{Random small things}
598 %************************************************************************
600 When printing export lists, we print like this:
602 AvailTC C [C, x, y] C(x,y)
603 AvailTC C [x, y] C!(x,y) -- Exporting x, y but not C
606 upp_avail :: AvailInfo -> SDoc
607 upp_avail (Avail name) = pprOccName (getOccName name)
608 upp_avail (AvailTC name []) = empty
609 upp_avail (AvailTC name ns) = hcat [pprOccName (getOccName name), bang, upp_export ns']
611 bang | name `elem` ns = empty
612 | otherwise = char '|'
613 ns' = filter (/= name) ns
615 upp_export :: [Name] -> SDoc
616 upp_export [] = empty
617 upp_export names = braces (hsep (map (pprOccName . getOccName) names))
619 upp_fixity :: (Name, Fixity) -> SDoc
620 upp_fixity (name, fixity) = hsep [ptext SLIT("0"), ppr fixity, ppr name, semi]
621 -- Dummy version number!
623 ppr_unqual_name :: NamedThing a => a -> SDoc -- Just its occurrence name
624 ppr_unqual_name name = pprOccName (getOccName name)
628 %************************************************************************
630 \subsection{Comparisons}
632 %************************************************************************
635 The various sorts above simply prevent unnecessary "wobbling" when
636 things change that don't have to. We therefore compare lexically, not
640 lt_avail :: AvailInfo -> AvailInfo -> Bool
642 a1 `lt_avail` a2 = availName a1 `lt_name` availName a2
644 lt_name :: Name -> Name -> Bool
645 n1 `lt_name` n2 = nameRdrName n1 < nameRdrName n2
647 lt_lexical :: NamedThing a => a -> a -> Bool
648 lt_lexical a1 a2 = getName a1 `lt_name` getName a2
650 lt_imp_vers :: ImportVersion a -> ImportVersion a -> Bool
651 lt_imp_vers (m1,_,_,_) (m2,_,_,_) = m1 < m2
653 sort_versions vs = sortLt lt_vers vs
655 lt_vers :: LocalVersion Name -> LocalVersion Name -> Bool
656 lt_vers (n1,v1) (n2,v2) = n1 `lt_name` n2
665 hPutCol hdl fmt xs = mapIO (printForIface hdl . fmt) xs
667 mapIO :: (a -> IO b) -> [a] -> IO ()
668 mapIO f [] = return ()
669 mapIO f (x:xs) = f x >> mapIO f xs