2 % (c) The University of Glasgow 2006
3 % (c) The GRASP/AQUA Project, Glasgow University, 1993-1998
8 -- The above warning supression flag is a temporary kludge.
9 -- While working on this module you are encouraged to remove it and fix
10 -- any warnings in the module. See
11 -- http://hackage.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#Warnings
17 mkIface, -- Build a ModIface from a ModGuts,
18 -- including computing version information
22 writeIfaceFile, -- Write the interface file
24 checkOldIface, -- See if recompilation is required, by
25 -- comparing version information
27 tyThingToIfaceDecl -- Converting things to their Iface equivalents
31 -----------------------------------------------
32 MkIface.lhs deals with versioning
33 -----------------------------------------------
35 Here's the version-related info in an interface file
37 module Foo 8 -- module-version
38 3 -- export-list-version
40 Usages: -- Version info for what this compilation of Foo imported
41 Baz 3 -- Module version
42 [4] -- The export-list version if Foo depended on it
43 (g,2) -- Function and its version
44 (T,1) -- Type and its version
46 <version> f :: Int -> Int {- Unfolding: \x -> Wib.t[2] x -}
47 -- The [2] says that f's unfolding
48 -- mentions verison 2 of Wib.t
50 -----------------------------------------------
52 -----------------------------------------------
55 * In the mi_usages information in an interface, we record the
56 version number of each free variable of the module
58 * In mkIface, we compute the version number of each exported thing A.f
59 by comparing its A.f's info with its new info, and bumping its
60 version number if it differs. If A.f mentions B.g, and B.g's version
61 number has changed, then we count A.f as having changed too.
63 * In checkOldIface we compare the mi_usages for the module with
64 the actual version info for all each thing recorded in mi_usages
69 We count A.f as changing if its fixity changes
73 If a rule changes, we want to recompile any module that might be
74 affected by that rule. For non-orphan rules, this is relatively easy.
75 If module M defines f, and a rule for f, just arrange that the version
76 number for M.f changes if any of the rules for M.f change. Any module
77 that does not depend on M.f can't be affected by the rule-change
80 Orphan rules (ones whose 'head function' is not defined in M) are
81 harder. Here's what we do.
83 * We have a per-module orphan-rule version number which changes if
84 any orphan rule changes. (It's unaffected by non-orphan rules.)
86 * We record usage info for any orphan module 'below' this one,
87 giving the orphan-rule version number. We recompile if this
90 The net effect is that if an orphan rule changes, we recompile every
91 module above it. That's very conservative, but it's devilishly hard
92 to know what it might affect, so we just have to be conservative.
96 In an iface file we have
98 instance Eq a => Eq [a] = dfun29
101 We have a version number for dfun29, covering its unfolding
102 etc. Suppose we are compiling a module M that imports A only
103 indirectly. If typechecking M uses this instance decl, we record the
104 dependency on A.dfun29 as if it were a free variable of the module
105 (via the tcg_inst_usages accumulator). That means that A will appear
106 in M's usage list. If the shape of the instance declaration changes,
107 then so will dfun29's version, triggering a recompilation.
109 Adding an instance declaration, or changing an instance decl that is
110 not currently used, is more tricky. (This really only makes a
111 difference when we have overlapping instance decls, because then the
112 new instance decl might kick in to override the old one.) We handle
113 this in a very similar way that we handle rules above.
115 * For non-orphan instance decls, identify one locally-defined tycon/class
116 mentioned in the decl. Treat the instance decl as part of the defn of that
117 tycon/class, so that if the shape of the instance decl changes, so does the
118 tycon/class; that in turn will force recompilation of anything that uses
121 * For orphan instance decls, act the same way as for orphan rules.
122 Indeed, we use the same global orphan-rule version number.
126 mkUsageInfo figures out what the ``usage information'' for this
127 moudule is; that is, what it must record in its interface file as the
130 We produce a line for every module B below the module, A, currently being
133 to record the fact that A does import B indirectly. This is used to decide
134 to look for B.hi rather than B.hi-boot when compiling a module that
135 imports A. This line says that A imports B, but uses nothing in it.
136 So we'll get an early bale-out when compiling A if B's version changes.
138 The usage information records:
141 \item (a) anything reachable from its body code
142 \item (b) any module exported with a @module Foo@
143 \item (c) anything reachable from an exported item
146 Why (b)? Because if @Foo@ changes then this module's export list
147 will change, so we must recompile this module at least as far as
148 making a new interface file --- but in practice that means complete
151 Why (c)? Consider this:
153 module A( f, g ) where | module B( f ) where
154 import B( f ) | f = h 3
158 Here, @B.f@ isn't used in A. Should we nevertheless record @B.f@ in
159 @A@'s usages? Our idea is that we aren't going to touch A.hi if it is
160 *identical* to what it was before. If anything about @B.f@ changes
161 than anyone who imports @A@ should be recompiled in case they use
162 @B.f@ (they'll get an early exit if they don't). So, if anything
163 about @B.f@ changes we'd better make sure that something in A.hi
164 changes, and the convenient way to do that is to record the version
165 number @B.f@ in A.hi in the usage list. If B.f changes that'll force a
166 complete recompiation of A, which is overkill but it's the only way to
167 write a new, slightly different, A.hi.
169 But the example is tricker. Even if @B.f@ doesn't change at all,
170 @B.h@ may do so, and this change may not be reflected in @f@'s version
171 number. But with -O, a module that imports A must be recompiled if
172 @B.h@ changes! So A must record a dependency on @B.h@. So we treat
173 the occurrence of @B.f@ in the export list *just as if* it were in the
174 code of A, and thereby haul in all the stuff reachable from it.
176 *** Conclusion: if A mentions B.f in its export list,
177 behave just as if A mentioned B.f in its source code,
178 and slurp in B.f and all its transitive closure ***
180 [NB: If B was compiled with -O, but A isn't, we should really *still*
181 haul in all the unfoldings for B, in case the module that imports A *is*
182 compiled with -O. I think this is the case.]
184 SimonM [30/11/2007]: I believe the above is all out of date; the
185 current implementation doesn't do it this way. Instead, when any of
186 the dependencies of a declaration changes, the version of the
187 declaration itself changes.
190 #include "HsVersions.h"
223 import PackageConfig hiding ( Version )
225 import BasicTypes hiding ( SuccessFlag(..) )
227 import Util hiding ( eqListBy )
240 %************************************************************************
242 \subsection{Completing an interface}
244 %************************************************************************
248 -> Maybe ModIface -- The old interface, if we have it
249 -> ModDetails -- The trimmed, tidied interface
250 -> ModGuts -- Usages, deprecations, etc
251 -> IO (ModIface, -- The new one, complete with decls and versions
252 Bool) -- True <=> there was an old Iface, and the new one
253 -- is identical, so no need to write it
255 mkIface hsc_env maybe_old_iface mod_details
256 ModGuts{ mg_module = this_mod,
258 mg_used_names = used_names,
260 mg_dir_imps = dir_imp_mods,
261 mg_rdr_env = rdr_env,
262 mg_fix_env = fix_env,
263 mg_deprecs = deprecs,
264 mg_hpc_info = hpc_info }
265 = mkIface_ hsc_env maybe_old_iface
266 this_mod is_boot used_names deps rdr_env
267 fix_env deprecs hpc_info dir_imp_mods mod_details
269 -- | make an interface from the results of typechecking only. Useful
270 -- for non-optimising compilation, or where we aren't generating any
271 -- object code at all ('HscNothing').
273 -> Maybe ModIface -- The old interface, if we have it
274 -> ModDetails -- gotten from mkBootModDetails, probably
275 -> TcGblEnv -- Usages, deprecations, etc
278 mkIfaceTc hsc_env maybe_old_iface mod_details
279 tc_result@TcGblEnv{ tcg_mod = this_mod,
281 tcg_imports = imports,
282 tcg_rdr_env = rdr_env,
283 tcg_fix_env = fix_env,
284 tcg_deprecs = deprecs,
285 tcg_hpc = other_hpc_info
288 used_names <- mkUsedNames tc_result
289 deps <- mkDependencies tc_result
290 let hpc_info = emptyHpcInfo other_hpc_info
291 mkIface_ hsc_env maybe_old_iface
292 this_mod (isHsBoot hsc_src) used_names deps rdr_env
293 fix_env deprecs hpc_info (imp_mods imports) mod_details
296 mkUsedNames :: TcGblEnv -> IO NameSet
298 TcGblEnv{ tcg_inst_uses = dfun_uses_var,
302 dfun_uses <- readIORef dfun_uses_var -- What dfuns are used
303 return (allUses dus `unionNameSets` dfun_uses)
305 mkDependencies :: TcGblEnv -> IO Dependencies
307 TcGblEnv{ tcg_mod = mod,
308 tcg_imports = imports,
312 th_used <- readIORef th_var -- Whether TH is used
314 dep_mods = eltsUFM (delFromUFM (imp_dep_mods imports) (moduleName mod))
315 -- M.hi-boot can be in the imp_dep_mods, but we must remove
316 -- it before recording the modules on which this one depends!
317 -- (We want to retain M.hi-boot in imp_dep_mods so that
318 -- loadHiBootInterface can see if M's direct imports depend
319 -- on M.hi-boot, and hence that we should do the hi-boot consistency
322 dir_imp_mods = imp_mods imports
324 -- Modules don't compare lexicographically usually,
325 -- but we want them to do so here.
326 le_mod :: Module -> Module -> Bool
327 le_mod m1 m2 = moduleNameFS (moduleName m1)
328 <= moduleNameFS (moduleName m2)
330 le_dep_mod :: (ModuleName, IsBootInterface)
331 -> (ModuleName, IsBootInterface) -> Bool
332 le_dep_mod (m1,_) (m2,_) = moduleNameFS m1 <= moduleNameFS m2
335 pkgs | th_used = insertList thPackageId (imp_dep_pkgs imports)
336 | otherwise = imp_dep_pkgs imports
338 return Deps { dep_mods = sortLe le_dep_mod dep_mods,
339 dep_pkgs = sortLe (<=) pkgs,
340 dep_orphs = sortLe le_mod (imp_orphs imports),
341 dep_finsts = sortLe le_mod (imp_finsts imports) }
342 -- sort to get into canonical order
345 mkIface_ hsc_env maybe_old_iface
346 this_mod is_boot used_names deps rdr_env fix_env src_deprecs hpc_info
348 ModDetails{ md_insts = insts,
349 md_fam_insts = fam_insts,
351 md_vect_info = vect_info,
353 md_exports = exports }
354 -- NB: notice that mkIface does not look at the bindings
355 -- only at the TypeEnv. The previous Tidy phase has
356 -- put exactly the info into the TypeEnv that we want
357 -- to expose in the interface
359 = do {eps <- hscEPS hsc_env
361 ; usages <- mkUsageInfo hsc_env dir_imp_mods (dep_mods deps) used_names
363 ; let { entities = typeEnvElts type_env ;
364 decls = [ tyThingToIfaceDecl entity
365 | entity <- entities,
366 let name = getName entity,
367 not (isImplicitTyThing entity),
368 -- No implicit Ids and class tycons in the interface file
369 not (isWiredInName name),
370 -- Nor wired-in things; the compiler knows about them anyhow
371 nameIsLocalOrFrom this_mod name ]
372 -- Sigh: see Note [Root-main Id] in TcRnDriver
374 ; fixities = [(occ,fix) | FixItem occ fix <- nameEnvElts fix_env]
375 ; deprecs = src_deprecs
376 ; iface_rules = map (coreRuleToIfaceRule this_mod) rules
377 ; iface_insts = map instanceToIfaceInst insts
378 ; iface_fam_insts = map famInstToIfaceFamInst fam_insts
379 ; iface_vect_info = flattenVectInfo vect_info
381 ; intermediate_iface = ModIface {
382 mi_module = this_mod,
386 mi_exports = mkIfaceExports exports,
388 -- Sort these lexicographically, so that
389 -- the result is stable across compilations
390 mi_insts = sortLe le_inst iface_insts,
391 mi_fam_insts= sortLe le_fam_inst iface_fam_insts,
392 mi_rules = sortLe le_rule iface_rules,
394 mi_vect_info = iface_vect_info,
396 mi_fixities = fixities,
397 mi_deprecs = deprecs,
398 mi_globals = Just rdr_env,
400 -- Left out deliberately: filled in by addVersionInfo
401 mi_mod_vers = initialVersion,
402 mi_exp_vers = initialVersion,
403 mi_rule_vers = initialVersion,
404 mi_orphan = False, -- Always set by addVersionInfo, but
405 -- it's a strict field, so we can't omit it.
406 mi_finsts = False, -- Ditto
407 mi_decls = deliberatelyOmitted "decls",
408 mi_ver_fn = deliberatelyOmitted "ver_fn",
409 mi_hpc = isHpcUsed hpc_info,
411 -- And build the cached values
412 mi_dep_fn = mkIfaceDepCache deprecs,
413 mi_fix_fn = mkIfaceFixCache fixities }
415 -- Add version information
416 ; ext_ver_fn = mkParentVerFun hsc_env eps
417 ; (new_iface, no_change_at_all, pp_diffs, pp_orphs)
418 = {-# SCC "versioninfo" #-}
419 addVersionInfo ext_ver_fn maybe_old_iface
420 intermediate_iface decls
424 ; when (isJust pp_orphs && dopt Opt_WarnOrphans dflags)
425 (printDump (expectJust "mkIface" pp_orphs))
426 ; when (dopt Opt_D_dump_hi_diffs dflags) (printDump pp_diffs)
427 ; dumpIfSet_dyn dflags Opt_D_dump_hi "FINAL INTERFACE"
428 (pprModIface new_iface)
430 -- bug #1617: on reload we weren't updating the PrintUnqualified
431 -- correctly. This stems from the fact that the interface had
432 -- not changed, so addVersionInfo returns the old ModIface
433 -- with the old GlobalRdrEnv (mi_globals).
434 ; let final_iface = new_iface{ mi_globals = Just rdr_env }
436 ; return (final_iface, no_change_at_all) }
438 r1 `le_rule` r2 = ifRuleName r1 <= ifRuleName r2
439 i1 `le_inst` i2 = ifDFun i1 `le_occ` ifDFun i2
440 i1 `le_fam_inst` i2 = ifFamInstTcName i1 `le_occ` ifFamInstTcName i2
442 le_occ :: Name -> Name -> Bool
443 -- Compare lexicographically by OccName, *not* by unique, because
444 -- the latter is not stable across compilations
445 le_occ n1 n2 = nameOccName n1 <= nameOccName n2
447 dflags = hsc_dflags hsc_env
448 deliberatelyOmitted x = panic ("Deliberately omitted: " ++ x)
449 ifFamInstTcName = ifaceTyConName . ifFamInstTyCon
451 flattenVectInfo (VectInfo { vectInfoVar = vVar
452 , vectInfoTyCon = vTyCon
455 ifaceVectInfoVar = [ Var.varName v
456 | (v, _) <- varEnvElts vVar],
457 ifaceVectInfoTyCon = [ tyConName t
458 | (t, t_v) <- nameEnvElts vTyCon
460 ifaceVectInfoTyConReuse = [ tyConName t
461 | (t, t_v) <- nameEnvElts vTyCon
465 -----------------------------
466 writeIfaceFile :: DynFlags -> ModLocation -> ModIface -> IO ()
467 writeIfaceFile dflags location new_iface
468 = do createDirectoryHierarchy (directoryOf hi_file_path)
469 writeBinIface dflags hi_file_path new_iface
470 where hi_file_path = ml_hi_file location
473 -- -----------------------------------------------------------------------------
474 -- Look up parents and versions of Names
476 -- This is like a global version of the mi_ver_fn field in each ModIface.
477 -- Given a Name, it finds the ModIface, and then uses mi_ver_fn to get
478 -- the parent and version info.
481 :: HscEnv -- needed to look up versions
482 -> ExternalPackageState -- ditto
483 -> (Name -> (OccName,Version))
484 mkParentVerFun hsc_env eps
487 mod = nameModule name
488 occ = nameOccName name
489 iface = lookupIfaceByModule (hsc_dflags hsc_env) hpt pit mod `orElse`
490 pprPanic "lookupVers2" (ppr mod <+> ppr occ)
492 mi_ver_fn iface occ `orElse`
493 pprPanic "lookupVers1" (ppr mod <+> ppr occ)
495 hpt = hsc_HPT hsc_env
498 -----------------------------------------------------------------------------
499 -- Compute version numbers for local decls
502 :: (Name -> (OccName,Version)) -- lookup parents and versions of names
503 -> Maybe ModIface -- The old interface, read from M.hi
504 -> ModIface -- The new interface (lacking decls)
505 -> [IfaceDecl] -- The new decls
506 -> (ModIface, -- Updated interface
507 Bool, -- True <=> no changes at all; no need to write Iface
509 Maybe SDoc) -- Warnings about orphans
511 addVersionInfo ver_fn Nothing new_iface new_decls
512 -- No old interface, so definitely write a new one!
513 = (new_iface { mi_orphan = not (null orph_insts && null orph_rules)
514 , mi_finsts = not . null $ mi_fam_insts new_iface
515 , mi_decls = [(initialVersion, decl) | decl <- new_decls]
516 , mi_ver_fn = mkIfaceVerCache (zip (repeat initialVersion)
520 ptext SLIT("No old interface file"),
521 pprOrphans orph_insts orph_rules)
523 orph_insts = filter (isNothing . ifInstOrph) (mi_insts new_iface)
524 orph_rules = filter (isNothing . ifRuleOrph) (mi_rules new_iface)
526 addVersionInfo ver_fn (Just old_iface@(ModIface {
527 mi_mod_vers = old_mod_vers,
528 mi_exp_vers = old_exp_vers,
529 mi_rule_vers = old_rule_vers,
530 mi_decls = old_decls,
531 mi_ver_fn = old_decl_vers,
532 mi_fix_fn = old_fixities }))
533 new_iface@(ModIface { mi_fix_fn = new_fixities })
536 = (old_iface, True, ptext SLIT("Interface file unchanged"), pp_orphs)
538 = (final_iface, False, vcat [ptext SLIT("Interface file has changed"),
539 nest 2 pp_diffs], pp_orphs)
541 final_iface = new_iface {
542 mi_mod_vers = bump_unless no_output_change old_mod_vers,
543 mi_exp_vers = bump_unless no_export_change old_exp_vers,
544 mi_rule_vers = bump_unless no_rule_change old_rule_vers,
545 mi_orphan = not (null new_orph_rules && null new_orph_insts),
546 mi_finsts = not . null $ mi_fam_insts new_iface,
547 mi_decls = decls_w_vers,
548 mi_ver_fn = mkIfaceVerCache decls_w_vers }
550 decls_w_vers = [(add_vers decl, decl) | decl <- new_decls]
553 (old_non_orph_insts, old_orph_insts) =
554 mkOrphMap ifInstOrph (mi_insts old_iface)
555 (new_non_orph_insts, new_orph_insts) =
556 mkOrphMap ifInstOrph (mi_insts new_iface)
557 old_fam_insts = mi_fam_insts old_iface
558 new_fam_insts = mi_fam_insts new_iface
559 same_insts occ = eqMaybeBy (eqListBy eqIfInst)
560 (lookupOccEnv old_non_orph_insts occ)
561 (lookupOccEnv new_non_orph_insts occ)
563 (old_non_orph_rules, old_orph_rules) =
564 mkOrphMap ifRuleOrph (mi_rules old_iface)
565 (new_non_orph_rules, new_orph_rules) =
566 mkOrphMap ifRuleOrph (mi_rules new_iface)
567 same_rules occ = eqMaybeBy (eqListBy eqIfRule)
568 (lookupOccEnv old_non_orph_rules occ)
569 (lookupOccEnv new_non_orph_rules occ)
571 -- Computing what changed
572 no_output_change = no_decl_change && no_rule_change &&
573 no_export_change && no_deprec_change
574 no_export_change = mi_exports new_iface == mi_exports old_iface
576 no_decl_change = isEmptyOccSet changed_occs
577 no_rule_change = not (changedWrtNames changed_occs (eqListBy eqIfRule old_orph_rules new_orph_rules)
578 || changedWrtNames changed_occs (eqListBy eqIfInst old_orph_insts new_orph_insts)
579 || changedWrtNames changed_occs (eqListBy eqIfFamInst old_fam_insts new_fam_insts))
580 no_deprec_change = mi_deprecs new_iface == mi_deprecs old_iface
582 -- If the usages havn't changed either, we don't need to write the interface file
583 no_other_changes = mi_usages new_iface == mi_usages old_iface &&
584 mi_deps new_iface == mi_deps old_iface &&
585 mi_hpc new_iface == mi_hpc old_iface
586 no_change_at_all = no_output_change && no_other_changes
588 pp_diffs = vcat [pp_change no_export_change "Export list"
589 (ppr old_exp_vers <+> arrow <+> ppr (mi_exp_vers final_iface)),
590 pp_change no_rule_change "Rules"
591 (ppr old_rule_vers <+> arrow <+> ppr (mi_rule_vers final_iface)),
592 pp_change no_deprec_change "Deprecations" empty,
593 pp_change no_other_changes "Usages" empty,
595 pp_change True what info = empty
596 pp_change False what info = text what <+> ptext SLIT("changed") <+> info
599 old_decl_env = mkOccEnv [(ifName decl, decl) | (_,decl) <- old_decls]
600 same_fixity n = bool (old_fixities n == new_fixities n)
603 -- Adding version info
604 new_version = bumpVersion old_mod_vers
605 -- Start from the old module version, not from
606 -- zero so that if you remove f, and then add
607 -- it again, you don't thereby reduce f's
610 add_vers decl | occ `elemOccSet` changed_occs = new_version
611 | otherwise = snd (expectJust "add_vers" (old_decl_vers occ))
612 -- If it's unchanged, there jolly well
613 where -- should be an old version number
617 -- Deciding which declarations have changed
619 -- For each local decl, the IfaceEq gives the list of things that
620 -- must be unchanged for the declaration as a whole to be unchanged.
621 eq_info :: [(OccName, IfaceEq)]
622 eq_info = map check_eq new_decls
624 | Just old_decl <- lookupOccEnv old_decl_env occ
625 = (occ, new_decl `eqIfDecl` old_decl &&& eq_indirects new_decl)
626 | otherwise {- No corresponding old decl -}
629 occ = ifName new_decl
631 eq_indirects :: IfaceDecl -> IfaceEq
632 -- When seeing if two decls are the same, remember to
633 -- check whether any relevant fixity or rules have changed
634 eq_indirects (IfaceId {ifName = occ}) = eq_ind_occ occ
635 eq_indirects (IfaceClass {ifName = cls_occ, ifSigs = sigs})
636 = same_insts cls_occ &&&
637 eq_ind_occs [op | IfaceClassOp op _ _ <- sigs]
638 eq_indirects (IfaceData {ifName = tc_occ, ifCons = cons})
639 = same_insts tc_occ &&& same_fixity tc_occ &&& -- The TyCon can have a fixity too
640 eq_ind_occs (map ifConOcc (visibleIfConDecls cons))
641 eq_indirects other = Equal -- Synonyms and foreign declarations
643 eq_ind_occ :: OccName -> IfaceEq -- For class ops and Ids; check fixity and rules
644 eq_ind_occ occ = same_fixity occ &&& same_rules occ
645 eq_ind_occs = foldr ((&&&) . eq_ind_occ) Equal
647 -- The Occs of declarations that changed.
648 changed_occs :: OccSet
649 changed_occs = computeChangedOccs ver_fn (mi_module new_iface)
650 (mi_usages old_iface) eq_info
654 pp_decl_diffs :: SDoc -- Nothing => no changes
656 | isEmptyOccSet changed_occs = empty
658 = vcat [ptext SLIT("Changed occs:") <+> ppr (occSetElts changed_occs),
659 ptext SLIT("Version change for these decls:"),
660 nest 2 (vcat (map show_change new_decls))]
662 eq_env = mkOccEnv eq_info
664 | not (occ `elemOccSet` changed_occs) = empty
666 = vcat [ppr occ <+> ppr (old_decl_vers occ) <+> arrow <+> ppr new_version,
669 occ = ifName new_decl
670 why = case lookupOccEnv eq_env occ of
671 Just (EqBut names) -> sep [ppr occ <> colon, ptext SLIT("Free vars (only) changed:") <> ppr names,
672 nest 2 (braces (fsep (map ppr (occSetElts
673 (occs `intersectOccSet` changed_occs)))))]
674 where occs = mkOccSet (map nameOccName (nameSetToList names))
676 | Just old_decl <- lookupOccEnv old_decl_env occ
677 -> vcat [ptext SLIT("Old:") <+> ppr old_decl,
678 ptext SLIT("New:") <+> ppr new_decl]
680 -> ppr occ <+> ptext SLIT("only in new interface")
681 other -> pprPanic "MkIface.show_change" (ppr occ)
683 pp_orphs = pprOrphans new_orph_insts new_orph_rules
686 pprOrphans insts rules
687 | null insts && null rules = Nothing
690 if null insts then empty else
691 hang (ptext SLIT("Warning: orphan instances:"))
692 2 (vcat (map ppr insts)),
693 if null rules then empty else
694 hang (ptext SLIT("Warning: orphan rules:"))
695 2 (vcat (map ppr rules))
699 :: (Name -> (OccName,Version)) -- get parents and versions
700 -> Module -- This module
701 -> [Usage] -- Usages from old iface
702 -> [(OccName, IfaceEq)] -- decl names, equality conditions
703 -> OccSet -- set of things that have changed
704 computeChangedOccs ver_fn this_module old_usages eq_info
705 = foldl add_changes emptyOccSet (stronglyConnComp edges)
708 -- return True if an external name has changed
709 name_changed :: Name -> Bool
711 | Just ents <- lookupUFM usg_modmap (moduleName mod),
712 Just v <- lookupUFM ents parent_occ
714 | modulePackageId mod == this_pkg
715 = WARN(True, ptext SLIT("computeChangedOccs") <+> ppr nm) True
716 -- should really be a panic, see #1959. The problem is that the usages doesn't
717 -- contain all the names that might be referred to by unfoldings. So as a
718 -- conservative workaround we just assume these names have changed.
719 | otherwise = False -- must be in another package
722 (parent_occ, new_version) = ver_fn nm
724 this_pkg = modulePackageId this_module
726 -- Turn the usages from the old ModIface into a mapping
727 usg_modmap = listToUFM [ (usg_name usg, listToUFM (usg_entities usg))
728 | usg <- old_usages ]
730 get_local_eq_info :: GenIfaceEq NameSet -> GenIfaceEq OccSet
731 get_local_eq_info Equal = Equal
732 get_local_eq_info NotEqual = NotEqual
733 get_local_eq_info (EqBut ns) = foldNameSet f Equal ns
734 where f name eq | nameModule name == this_module =
735 EqBut (unitOccSet (nameOccName name)) `and_occifeq` eq
736 | name_changed name = NotEqual
739 local_eq_infos = mapSnd get_local_eq_info eq_info
741 edges :: [((OccName, OccIfaceEq), Unique, [Unique])]
742 edges = [ (node, getUnique occ, map getUnique occs)
743 | node@(occ, iface_eq) <- local_eq_infos
744 , let occs = case iface_eq of
745 EqBut occ_set -> occSetElts occ_set
748 -- Changes in declarations
749 add_changes :: OccSet -> SCC (OccName, OccIfaceEq) -> OccSet
750 add_changes so_far (AcyclicSCC (occ, iface_eq))
751 | changedWrt so_far iface_eq -- This one has changed
752 = extendOccSet so_far occ
753 add_changes so_far (CyclicSCC pairs)
754 | changedWrt so_far (foldr1 and_occifeq iface_eqs)
755 -- One of this group has changed
756 = extendOccSetList so_far occs
757 where (occs, iface_eqs) = unzip pairs
758 add_changes so_far other = so_far
760 type OccIfaceEq = GenIfaceEq OccSet
762 instance Outputable OccIfaceEq where
763 ppr Equal = ptext SLIT("Equal")
764 ppr NotEqual = ptext SLIT("NotEqual")
765 ppr (EqBut occset) = ptext SLIT("EqBut") <+> ppr (occSetElts occset)
767 changedWrt :: OccSet -> OccIfaceEq -> Bool
768 changedWrt so_far Equal = False
769 changedWrt so_far NotEqual = True
770 changedWrt so_far (EqBut kids) = so_far `intersectsOccSet` kids
772 changedWrtNames :: OccSet -> IfaceEq -> Bool
773 changedWrtNames so_far Equal = False
774 changedWrtNames so_far NotEqual = True
775 changedWrtNames so_far (EqBut kids) =
776 so_far `intersectsOccSet` mkOccSet (map nameOccName (nameSetToList kids))
778 and_occifeq :: OccIfaceEq -> OccIfaceEq -> OccIfaceEq
779 Equal `and_occifeq` x = x
780 NotEqual `and_occifeq` x = NotEqual
781 EqBut nms `and_occifeq` Equal = EqBut nms
782 EqBut nms `and_occifeq` NotEqual = NotEqual
783 EqBut nms1 `and_occifeq` EqBut nms2 = EqBut (nms1 `unionOccSets` nms2)
785 ----------------------
786 -- mkOrphMap partitions instance decls or rules into
787 -- (a) an OccEnv for ones that are not orphans,
788 -- mapping the local OccName to a list of its decls
789 -- (b) a list of orphan decls
790 mkOrphMap :: (decl -> Maybe OccName) -- (Just occ) for a non-orphan decl, keyed by occ
791 -- Nothing for an orphan decl
792 -> [decl] -- Sorted into canonical order
793 -> (OccEnv [decl], -- Non-orphan decls associated with their key;
794 -- each sublist in canonical order
795 [decl]) -- Orphan decls; in canonical order
796 mkOrphMap get_key decls
797 = foldl go (emptyOccEnv, []) decls
799 go (non_orphs, orphs) d
800 | Just occ <- get_key d
801 = (extendOccEnv_C (\ ds _ -> d:ds) non_orphs occ [d], orphs)
802 | otherwise = (non_orphs, d:orphs)
804 ----------------------
805 bump_unless :: Bool -> Version -> Version
806 bump_unless True v = v -- True <=> no change
807 bump_unless False v = bumpVersion v
811 %*********************************************************
813 \subsection{Keeping track of what we've slurped, and version numbers}
815 %*********************************************************
819 mkUsageInfo :: HscEnv
820 -> ModuleEnv (Module, [(ModuleName, Bool, SrcSpan)])
821 -> [(ModuleName, IsBootInterface)]
822 -> NameSet -> IO [Usage]
823 mkUsageInfo hsc_env dir_imp_mods dep_mods used_names
824 = do { eps <- hscEPS hsc_env
825 ; let usages = mk_usage_info (eps_PIT eps) hsc_env
826 dir_imp_mods dep_mods used_names
827 ; usages `seqList` return usages }
828 -- seq the list of Usages returned: occasionally these
829 -- don't get evaluated for a while and we can end up hanging on to
830 -- the entire collection of Ifaces.
832 mk_usage_info :: PackageIfaceTable
834 -> ModuleEnv (Module, [(ModuleName, Bool, SrcSpan)])
835 -> [(ModuleName, IsBootInterface)]
838 mk_usage_info pit hsc_env dir_imp_mods dep_mods used_names
839 = mapCatMaybes mkUsage dep_mods
840 -- ToDo: do we need to sort into canonical order?
842 hpt = hsc_HPT hsc_env
843 dflags = hsc_dflags hsc_env
845 -- ent_map groups together all the things imported and used
846 -- from a particular module in this package
847 ent_map :: ModuleEnv [OccName]
848 ent_map = foldNameSet add_mv emptyModuleEnv used_names
850 | isWiredInName name = mv_map -- ignore wired-in names
852 = case nameModule_maybe name of
853 Nothing -> mv_map -- ignore internal names
854 Just mod -> extendModuleEnv_C add_item mv_map mod [occ]
856 occ = nameOccName name
857 add_item occs _ = occ:occs
859 depend_on_exports mod = case lookupModuleEnv dir_imp_mods mod of
860 Just (_, xs) -> any (\(_, no_imp, _) -> not no_imp) xs
863 -- We want to create a Usage for a home module if
864 -- a) we used something from; has something in used_names
865 -- b) we imported all of it, even if we used nothing from it
866 -- (need to recompile if its export list changes: export_vers)
867 -- c) is a home-package orphan or family-instance module (need to
868 -- recompile if its instance decls change: rules_vers)
869 mkUsage :: (ModuleName, IsBootInterface) -> Maybe Usage
870 mkUsage (mod_name, _)
871 | isNothing maybe_iface -- We can't depend on it if we didn't
872 || (null used_occs -- load its interface.
873 && isNothing export_vers
876 = Nothing -- Record no usage info
879 = Just (Usage { usg_name = mod_name,
881 usg_exports = export_vers,
882 usg_entities = fmToList ent_vers,
883 usg_rules = rules_vers })
885 maybe_iface = lookupIfaceByModule dflags hpt pit mod
886 -- In one-shot mode, the interfaces for home-package
887 -- modules accumulate in the PIT not HPT. Sigh.
889 mod = mkModule (thisPackage dflags) mod_name
891 Just iface = maybe_iface
892 orphan_mod = mi_orphan iface
893 finsts_mod = mi_finsts iface
894 version_env = mi_ver_fn iface
895 mod_vers = mi_mod_vers iface
896 rules_vers = mi_rule_vers iface
897 export_vers | depend_on_exports mod = Just (mi_exp_vers iface)
898 | otherwise = Nothing
900 used_occs = lookupModuleEnv ent_map mod `orElse` []
902 -- Making a FiniteMap here ensures that (a) we remove duplicates
903 -- when we have usages on several subordinates of a single parent,
904 -- and (b) that the usages emerge in a canonical order, which
905 -- is why we use FiniteMap rather than OccEnv: FiniteMap works
906 -- using Ord on the OccNames, which is a lexicographic ordering.
907 ent_vers :: FiniteMap OccName Version
908 ent_vers = listToFM (map lookup_occ used_occs)
911 case version_env occ of
912 Nothing -> pprTrace "hmm, strange" (ppr mod <+> ppr occ) $
913 (occ, initialVersion) -- does this ever happen?
914 Just (parent, version) -> (parent, version)
918 mkIfaceExports :: [AvailInfo]
919 -> [(Module, [GenAvailInfo OccName])]
920 -- Group by module and sort by occurrence
921 -- This keeps the list in canonical order
922 mkIfaceExports exports
923 = [ (mod, eltsFM avails)
924 | (mod, avails) <- fmToList groupFM
927 -- Group by the module where the exported entities are defined
928 -- (which may not be the same for all Names in an Avail)
929 -- Deliberately use FiniteMap rather than UniqFM so we
930 -- get a canonical ordering
931 groupFM :: ModuleEnv (FiniteMap FastString (GenAvailInfo OccName))
932 groupFM = foldl add emptyModuleEnv exports
934 add_one :: ModuleEnv (FiniteMap FastString (GenAvailInfo OccName))
935 -> Module -> GenAvailInfo OccName
936 -> ModuleEnv (FiniteMap FastString (GenAvailInfo OccName))
937 add_one env mod avail
938 = extendModuleEnv_C plusFM env mod
939 (unitFM (occNameFS (availName avail)) avail)
941 -- NB: we should not get T(X) and T(Y) in the export list
942 -- else the plusFM will simply discard one! They
943 -- should have been combined by now.
945 = add_one env (nameModule n) (Avail (nameOccName n))
947 add env (AvailTC tc ns)
948 = foldl add_for_mod env mods
950 tc_occ = nameOccName tc
951 mods = nub (map nameModule ns)
952 -- Usually just one, but see Note [Original module]
955 = add_one env mod (AvailTC tc_occ (sort names_from_mod))
956 -- NB. sort the children, we need a canonical order
958 names_from_mod = [nameOccName n | n <- ns, nameModule n == mod]
961 Note [Orignal module]
962 ~~~~~~~~~~~~~~~~~~~~~
964 module X where { data family T }
965 module Y( T(..) ) where { import X; data instance T Int = MkT Int }
966 The exported Avail from Y will look like
969 - only MkT is brought into scope by the data instance;
970 - but the parent (used for grouping and naming in T(..) exports) is X.T
971 - and in this case we export X.T too
973 In the result of MkIfaceExports, the names are grouped by defining module,
974 so we may need to split up a single Avail into multiple ones.
977 %************************************************************************
979 Load the old interface file for this module (unless
980 we have it aleady), and check whether it is up to date
983 %************************************************************************
986 checkOldIface :: HscEnv
988 -> Bool -- Source unchanged
989 -> Maybe ModIface -- Old interface from compilation manager, if any
990 -> IO (RecompileRequired, Maybe ModIface)
992 checkOldIface hsc_env mod_summary source_unchanged maybe_iface
993 = do { showPass (hsc_dflags hsc_env)
994 ("Checking old interface for " ++
995 showSDoc (ppr (ms_mod mod_summary))) ;
997 ; initIfaceCheck hsc_env $
998 check_old_iface hsc_env mod_summary source_unchanged maybe_iface
1001 check_old_iface hsc_env mod_summary source_unchanged maybe_iface
1002 = do -- CHECK WHETHER THE SOURCE HAS CHANGED
1003 { ifM (not source_unchanged)
1004 (traceHiDiffs (nest 4 (text "Source file changed or recompilation check turned off")))
1006 -- If the source has changed and we're in interactive mode, avoid reading
1007 -- an interface; just return the one we might have been supplied with.
1008 ; let dflags = hsc_dflags hsc_env
1009 ; if not (isObjectTarget (hscTarget dflags)) && not source_unchanged then
1010 return (outOfDate, maybe_iface)
1012 case maybe_iface of {
1013 Just old_iface -> do -- Use the one we already have
1014 { traceIf (text "We already have the old interface for" <+> ppr (ms_mod mod_summary))
1015 ; recomp <- checkVersions hsc_env source_unchanged mod_summary old_iface
1016 ; return (recomp, Just old_iface) }
1020 -- Try and read the old interface for the current module
1021 -- from the .hi file left from the last time we compiled it
1022 { let iface_path = msHiFilePath mod_summary
1023 ; read_result <- readIface (ms_mod mod_summary) iface_path False
1024 ; case read_result of {
1025 Failed err -> do -- Old interface file not found, or garbled; give up
1026 { traceIf (text "FYI: cannot read old interface file:"
1028 ; return (outOfDate, Nothing) }
1030 ; Succeeded iface -> do
1032 -- We have got the old iface; check its versions
1033 { traceIf (text "Read the interface file" <+> text iface_path)
1034 ; recomp <- checkVersions hsc_env source_unchanged mod_summary iface
1035 ; returnM (recomp, Just iface)
1040 @recompileRequired@ is called from the HscMain. It checks whether
1041 a recompilation is required. It needs access to the persistent state,
1042 finder, etc, because it may have to load lots of interface files to
1043 check their versions.
1046 type RecompileRequired = Bool
1047 upToDate = False -- Recompile not required
1048 outOfDate = True -- Recompile required
1050 checkVersions :: HscEnv
1051 -> Bool -- True <=> source unchanged
1053 -> ModIface -- Old interface
1054 -> IfG RecompileRequired
1055 checkVersions hsc_env source_unchanged mod_summary iface
1056 | not source_unchanged
1059 = do { traceHiDiffs (text "Considering whether compilation is required for" <+>
1060 ppr (mi_module iface) <> colon)
1062 ; recomp <- checkDependencies hsc_env mod_summary iface
1063 ; if recomp then return outOfDate else do {
1065 -- Source code unchanged and no errors yet... carry on
1067 -- First put the dependent-module info, read from the old interface, into the envt,
1068 -- so that when we look for interfaces we look for the right one (.hi or .hi-boot)
1070 -- It's just temporary because either the usage check will succeed
1071 -- (in which case we are done with this module) or it'll fail (in which
1072 -- case we'll compile the module from scratch anyhow).
1074 -- We do this regardless of compilation mode, although in --make mode
1075 -- all the dependent modules should be in the HPT already, so it's
1077 updateEps_ $ \eps -> eps { eps_is_boot = mod_deps }
1079 ; let this_pkg = thisPackage (hsc_dflags hsc_env)
1080 ; checkList [checkModUsage this_pkg u | u <- mi_usages iface]
1083 -- This is a bit of a hack really
1084 mod_deps :: ModuleNameEnv (ModuleName, IsBootInterface)
1085 mod_deps = mkModDeps (dep_mods (mi_deps iface))
1088 -- If the direct imports of this module are resolved to targets that
1089 -- are not among the dependencies of the previous interface file,
1090 -- then we definitely need to recompile. This catches cases like
1091 -- - an exposed package has been upgraded
1092 -- - we are compiling with different package flags
1093 -- - a home module that was shadowing a package module has been removed
1094 -- - a new home module has been added that shadows a package module
1097 -- Returns True if recompilation is required.
1098 checkDependencies :: HscEnv -> ModSummary -> ModIface -> IfG RecompileRequired
1099 checkDependencies hsc_env summary iface
1100 = orM (map dep_missing (ms_imps summary ++ ms_srcimps summary))
1102 prev_dep_mods = dep_mods (mi_deps iface)
1103 prev_dep_pkgs = dep_pkgs (mi_deps iface)
1105 this_pkg = thisPackage (hsc_dflags hsc_env)
1107 orM = foldr f (return False)
1108 where f m rest = do b <- m; if b then return True else rest
1110 dep_missing (L _ mod) = do
1111 find_res <- ioToIOEnv $ findImportedModule hsc_env mod Nothing
1115 -> if moduleName mod `notElem` map fst prev_dep_mods
1116 then do traceHiDiffs $
1117 text "imported module " <> quotes (ppr mod) <>
1118 text " not among previous dependencies"
1123 -> if pkg `notElem` prev_dep_pkgs
1124 then do traceHiDiffs $
1125 text "imported module " <> quotes (ppr mod) <>
1126 text " is from package " <> quotes (ppr pkg) <>
1127 text ", which is not among previous dependencies"
1131 where pkg = modulePackageId mod
1132 _otherwise -> return outOfDate
1134 checkModUsage :: PackageId ->Usage -> IfG RecompileRequired
1135 -- Given the usage information extracted from the old
1136 -- M.hi file for the module being compiled, figure out
1137 -- whether M needs to be recompiled.
1139 checkModUsage this_pkg (Usage { usg_name = mod_name, usg_mod = old_mod_vers,
1140 usg_rules = old_rule_vers,
1141 usg_exports = maybe_old_export_vers,
1142 usg_entities = old_decl_vers })
1143 = -- Load the imported interface is possible
1145 doc_str = sep [ptext SLIT("need version info for"), ppr mod_name]
1147 traceHiDiffs (text "Checking usages for module" <+> ppr mod_name) `thenM_`
1150 mod = mkModule this_pkg mod_name
1152 loadInterface doc_str mod ImportBySystem `thenM` \ mb_iface ->
1153 -- Load the interface, but don't complain on failure;
1154 -- Instead, get an Either back which we can test
1157 Failed exn -> (out_of_date (sep [ptext SLIT("Can't find version number for module"),
1159 -- Couldn't find or parse a module mentioned in the
1160 -- old interface file. Don't complain -- it might just be that
1161 -- the current module doesn't need that import and it's been deleted
1165 new_mod_vers = mi_mod_vers iface
1166 new_decl_vers = mi_ver_fn iface
1167 new_export_vers = mi_exp_vers iface
1168 new_rule_vers = mi_rule_vers iface
1171 checkModuleVersion old_mod_vers new_mod_vers `thenM` \ recompile ->
1172 if not recompile then
1176 -- CHECK EXPORT LIST
1177 if checkExportList maybe_old_export_vers new_export_vers then
1178 out_of_date_vers (ptext SLIT(" Export list changed"))
1179 (expectJust "checkModUsage" maybe_old_export_vers)
1184 if old_rule_vers /= new_rule_vers then
1185 out_of_date_vers (ptext SLIT(" Rules changed"))
1186 old_rule_vers new_rule_vers
1189 -- CHECK ITEMS ONE BY ONE
1190 checkList [checkEntityUsage new_decl_vers u | u <- old_decl_vers] `thenM` \ recompile ->
1192 returnM outOfDate -- This one failed, so just bail out now
1194 up_to_date (ptext SLIT(" Great! The bits I use are up to date"))
1197 ------------------------
1198 checkModuleVersion old_mod_vers new_mod_vers
1199 | new_mod_vers == old_mod_vers
1200 = up_to_date (ptext SLIT("Module version unchanged"))
1203 = out_of_date_vers (ptext SLIT(" Module version has changed"))
1204 old_mod_vers new_mod_vers
1206 ------------------------
1207 checkExportList Nothing new_vers = upToDate
1208 checkExportList (Just v) new_vers = v /= new_vers
1210 ------------------------
1211 checkEntityUsage new_vers (name,old_vers)
1212 = case new_vers name of
1214 Nothing -> -- We used it before, but it ain't there now
1215 out_of_date (sep [ptext SLIT("No longer exported:"), ppr name])
1217 Just (_, new_vers) -- It's there, but is it up to date?
1218 | new_vers == old_vers -> traceHiDiffs (text " Up to date" <+> ppr name <+> parens (ppr new_vers)) `thenM_`
1220 | otherwise -> out_of_date_vers (ptext SLIT(" Out of date:") <+> ppr name)
1223 up_to_date msg = traceHiDiffs msg `thenM_` returnM upToDate
1224 out_of_date msg = traceHiDiffs msg `thenM_` returnM outOfDate
1225 out_of_date_vers msg old_vers new_vers
1226 = out_of_date (hsep [msg, ppr old_vers, ptext SLIT("->"), ppr new_vers])
1228 ----------------------
1229 checkList :: [IfG RecompileRequired] -> IfG RecompileRequired
1230 -- This helper is used in two places
1231 checkList [] = returnM upToDate
1232 checkList (check:checks) = check `thenM` \ recompile ->
1239 %************************************************************************
1241 Converting things to their Iface equivalents
1243 %************************************************************************
1246 tyThingToIfaceDecl :: TyThing -> IfaceDecl
1247 -- Assumption: the thing is already tidied, so that locally-bound names
1248 -- (lambdas, for-alls) already have non-clashing OccNames
1249 -- Reason: Iface stuff uses OccNames, and the conversion here does
1250 -- not do tidying on the way
1251 tyThingToIfaceDecl (AnId id)
1252 = IfaceId { ifName = getOccName id,
1253 ifType = toIfaceType (idType id),
1256 info = case toIfaceIdInfo (idInfo id) of
1258 items -> HasInfo items
1260 tyThingToIfaceDecl (AClass clas)
1261 = IfaceClass { ifCtxt = toIfaceContext sc_theta,
1262 ifName = getOccName clas,
1263 ifTyVars = toIfaceTvBndrs clas_tyvars,
1264 ifFDs = map toIfaceFD clas_fds,
1265 ifATs = map (tyThingToIfaceDecl . ATyCon) clas_ats,
1266 ifSigs = map toIfaceClassOp op_stuff,
1267 ifRec = boolToRecFlag (isRecursiveTyCon tycon) }
1269 (clas_tyvars, clas_fds, sc_theta, _, clas_ats, op_stuff)
1270 = classExtraBigSig clas
1271 tycon = classTyCon clas
1273 toIfaceClassOp (sel_id, def_meth)
1274 = ASSERT(sel_tyvars == clas_tyvars)
1275 IfaceClassOp (getOccName sel_id) def_meth (toIfaceType op_ty)
1277 -- Be careful when splitting the type, because of things
1278 -- like class Foo a where
1279 -- op :: (?x :: String) => a -> a
1280 -- and class Baz a where
1281 -- op :: (Ord a) => a -> a
1282 (sel_tyvars, rho_ty) = splitForAllTys (idType sel_id)
1283 op_ty = funResultTy rho_ty
1285 toIfaceFD (tvs1, tvs2) = (map getFS tvs1, map getFS tvs2)
1287 tyThingToIfaceDecl (ATyCon tycon)
1289 = IfaceSyn { ifName = getOccName tycon,
1290 ifTyVars = toIfaceTvBndrs tyvars,
1291 ifOpenSyn = syn_isOpen,
1292 ifSynRhs = toIfaceType syn_tyki,
1293 ifFamInst = famInstToIface (tyConFamInst_maybe tycon)
1297 = IfaceData { ifName = getOccName tycon,
1298 ifTyVars = toIfaceTvBndrs tyvars,
1299 ifCtxt = toIfaceContext (tyConStupidTheta tycon),
1300 ifCons = ifaceConDecls (algTyConRhs tycon),
1301 ifRec = boolToRecFlag (isRecursiveTyCon tycon),
1302 ifGadtSyntax = isGadtSyntaxTyCon tycon,
1303 ifGeneric = tyConHasGenerics tycon,
1304 ifFamInst = famInstToIface (tyConFamInst_maybe tycon)}
1306 | isForeignTyCon tycon
1307 = IfaceForeign { ifName = getOccName tycon,
1308 ifExtName = tyConExtName tycon }
1310 | otherwise = pprPanic "toIfaceDecl" (ppr tycon)
1312 tyvars = tyConTyVars tycon
1313 (syn_isOpen, syn_tyki) = case synTyConRhs tycon of
1314 OpenSynTyCon ki _ -> (True , ki)
1315 SynonymTyCon ty -> (False, ty)
1317 ifaceConDecls (NewTyCon { data_con = con }) =
1318 IfNewTyCon (ifaceConDecl con)
1319 ifaceConDecls (DataTyCon { data_cons = cons }) =
1320 IfDataTyCon (map ifaceConDecl cons)
1321 ifaceConDecls OpenTyCon {} = IfOpenDataTyCon
1322 ifaceConDecls AbstractTyCon = IfAbstractTyCon
1323 -- The last case happens when a TyCon has been trimmed during tidying
1324 -- Furthermore, tyThingToIfaceDecl is also used
1325 -- in TcRnDriver for GHCi, when browsing a module, in which case the
1326 -- AbstractTyCon case is perfectly sensible.
1328 ifaceConDecl data_con
1329 = IfCon { ifConOcc = getOccName (dataConName data_con),
1330 ifConInfix = dataConIsInfix data_con,
1331 ifConUnivTvs = toIfaceTvBndrs (dataConUnivTyVars data_con),
1332 ifConExTvs = toIfaceTvBndrs (dataConExTyVars data_con),
1333 ifConEqSpec = to_eq_spec (dataConEqSpec data_con),
1334 ifConCtxt = toIfaceContext (dataConEqTheta data_con ++ dataConDictTheta data_con),
1335 ifConArgTys = map toIfaceType (dataConOrigArgTys data_con),
1336 ifConFields = map getOccName
1337 (dataConFieldLabels data_con),
1338 ifConStricts = dataConStrictMarks data_con }
1340 to_eq_spec spec = [(getOccName tv, toIfaceType ty) | (tv,ty) <- spec]
1342 famInstToIface Nothing = Nothing
1343 famInstToIface (Just (famTyCon, instTys)) =
1344 Just (toIfaceTyCon famTyCon, map toIfaceType instTys)
1346 tyThingToIfaceDecl (ADataCon dc)
1347 = pprPanic "toIfaceDecl" (ppr dc) -- Should be trimmed out earlier
1350 getFS x = occNameFS (getOccName x)
1352 --------------------------
1353 instanceToIfaceInst :: Instance -> IfaceInst
1354 instanceToIfaceInst ispec@(Instance { is_dfun = dfun_id, is_flag = oflag,
1355 is_cls = cls_name, is_tcs = mb_tcs })
1356 = ASSERT( cls_name == className cls )
1357 IfaceInst { ifDFun = dfun_name,
1359 ifInstCls = cls_name,
1360 ifInstTys = map do_rough mb_tcs,
1363 do_rough Nothing = Nothing
1364 do_rough (Just n) = Just (toIfaceTyCon_name n)
1366 dfun_name = idName dfun_id
1367 mod = nameModule dfun_name
1368 is_local name = nameIsLocalOrFrom mod name
1370 -- Compute orphanhood. See Note [Orphans] in IfaceSyn
1371 (_, _, cls, tys) = tcSplitDFunTy (idType dfun_id)
1372 -- Slightly awkward: we need the Class to get the fundeps
1373 (tvs, fds) = classTvsFds cls
1374 arg_names = [filterNameSet is_local (tyClsNamesOfType ty) | ty <- tys]
1375 orph | is_local cls_name = Just (nameOccName cls_name)
1376 | all isJust mb_ns = head mb_ns
1377 | otherwise = Nothing
1379 mb_ns :: [Maybe OccName] -- One for each fundep; a locally-defined name
1380 -- that is not in the "determined" arguments
1381 mb_ns | null fds = [choose_one arg_names]
1382 | otherwise = map do_one fds
1383 do_one (ltvs,rtvs) = choose_one [ns | (tv,ns) <- tvs `zip` arg_names
1384 , not (tv `elem` rtvs)]
1386 choose_one :: [NameSet] -> Maybe OccName
1387 choose_one nss = case nameSetToList (unionManyNameSets nss) of
1389 (n:ns) -> Just (nameOccName n)
1391 --------------------------
1392 famInstToIfaceFamInst :: FamInst -> IfaceFamInst
1393 famInstToIfaceFamInst fi@(FamInst { fi_tycon = tycon,
1394 fi_fam = fam, fi_tcs = mb_tcs })
1395 = IfaceFamInst { ifFamInstTyCon = toIfaceTyCon tycon
1396 , ifFamInstFam = fam
1397 , ifFamInstTys = map do_rough mb_tcs }
1399 do_rough Nothing = Nothing
1400 do_rough (Just n) = Just (toIfaceTyCon_name n)
1402 --------------------------
1403 toIfaceLetBndr id = IfLetBndr (occNameFS (getOccName id))
1404 (toIfaceType (idType id))
1407 -- Stripped-down version of tcIfaceIdInfo
1408 -- Change this if you want to export more IdInfo for
1409 -- non-top-level Ids. Don't forget to change
1410 -- CoreTidy.tidyLetBndr too!
1412 -- See Note [IdInfo on nested let-bindings] in IfaceSyn
1414 inline_prag = inlinePragInfo id_info
1415 prag_info | isAlwaysActive inline_prag = NoInfo
1416 | otherwise = HasInfo [HsInline inline_prag]
1418 --------------------------
1419 toIfaceIdInfo :: IdInfo -> [IfaceInfoItem]
1420 toIfaceIdInfo id_info
1421 = catMaybes [arity_hsinfo, caf_hsinfo, strict_hsinfo,
1422 inline_hsinfo, wrkr_hsinfo, unfold_hsinfo]
1424 ------------ Arity --------------
1425 arity_info = arityInfo id_info
1426 arity_hsinfo | arity_info == 0 = Nothing
1427 | otherwise = Just (HsArity arity_info)
1429 ------------ Caf Info --------------
1430 caf_info = cafInfo id_info
1431 caf_hsinfo = case caf_info of
1432 NoCafRefs -> Just HsNoCafRefs
1435 ------------ Strictness --------------
1436 -- No point in explicitly exporting TopSig
1437 strict_hsinfo = case newStrictnessInfo id_info of
1438 Just sig | not (isTopSig sig) -> Just (HsStrictness sig)
1441 ------------ Worker --------------
1442 work_info = workerInfo id_info
1443 has_worker = workerExists work_info
1444 wrkr_hsinfo = case work_info of
1445 HasWorker work_id wrap_arity ->
1446 Just (HsWorker ((idName work_id)) wrap_arity)
1449 ------------ Unfolding --------------
1450 -- The unfolding is redundant if there is a worker
1451 unfold_info = unfoldingInfo id_info
1452 rhs = unfoldingTemplate unfold_info
1453 no_unfolding = neverUnfold unfold_info
1454 -- The CoreTidy phase retains unfolding info iff
1455 -- we want to expose the unfolding, taking into account
1456 -- unconditional NOINLINE, etc. See TidyPgm.addExternal
1457 unfold_hsinfo | no_unfolding = Nothing
1458 | has_worker = Nothing -- Unfolding is implicit
1459 | otherwise = Just (HsUnfold (toIfaceExpr rhs))
1461 ------------ Inline prag --------------
1462 inline_prag = inlinePragInfo id_info
1463 inline_hsinfo | isAlwaysActive inline_prag = Nothing
1464 | no_unfolding && not has_worker = Nothing
1465 -- If the iface file give no unfolding info, we
1466 -- don't need to say when inlining is OK!
1467 | otherwise = Just (HsInline inline_prag)
1469 --------------------------
1470 coreRuleToIfaceRule :: Module -> CoreRule -> IfaceRule
1471 coreRuleToIfaceRule mod (BuiltinRule { ru_fn = fn})
1472 = pprTrace "toHsRule: builtin" (ppr fn) $
1475 coreRuleToIfaceRule mod (Rule { ru_name = name, ru_fn = fn,
1476 ru_act = act, ru_bndrs = bndrs,
1477 ru_args = args, ru_rhs = rhs })
1478 = IfaceRule { ifRuleName = name, ifActivation = act,
1479 ifRuleBndrs = map toIfaceBndr bndrs,
1481 ifRuleArgs = map do_arg args,
1482 ifRuleRhs = toIfaceExpr rhs,
1485 -- For type args we must remove synonyms from the outermost
1486 -- level. Reason: so that when we read it back in we'll
1487 -- construct the same ru_rough field as we have right now;
1489 do_arg (Type ty) = IfaceType (toIfaceType (deNoteType ty))
1490 do_arg arg = toIfaceExpr arg
1492 -- Compute orphanhood. See Note [Orphans] in IfaceSyn
1493 -- A rule is an orphan only if none of the variables
1494 -- mentioned on its left-hand side are locally defined
1495 lhs_names = fn : nameSetToList (exprsFreeNames args)
1496 -- No need to delete bndrs, because
1497 -- exprsFreeNames finds only External names
1499 orph = case filter (nameIsLocalOrFrom mod) lhs_names of
1500 (n:ns) -> Just (nameOccName n)
1503 bogusIfaceRule :: Name -> IfaceRule
1504 bogusIfaceRule id_name
1505 = IfaceRule { ifRuleName = FSLIT("bogus"), ifActivation = NeverActive,
1506 ifRuleBndrs = [], ifRuleHead = id_name, ifRuleArgs = [],
1507 ifRuleRhs = IfaceExt id_name, ifRuleOrph = Nothing }
1509 ---------------------
1510 toIfaceExpr :: CoreExpr -> IfaceExpr
1511 toIfaceExpr (Var v) = toIfaceVar v
1512 toIfaceExpr (Lit l) = IfaceLit l
1513 toIfaceExpr (Type ty) = IfaceType (toIfaceType ty)
1514 toIfaceExpr (Lam x b) = IfaceLam (toIfaceBndr x) (toIfaceExpr b)
1515 toIfaceExpr (App f a) = toIfaceApp f [a]
1516 toIfaceExpr (Case s x ty as) = IfaceCase (toIfaceExpr s) (getFS x) (toIfaceType ty) (map toIfaceAlt as)
1517 toIfaceExpr (Let b e) = IfaceLet (toIfaceBind b) (toIfaceExpr e)
1518 toIfaceExpr (Cast e co) = IfaceCast (toIfaceExpr e) (toIfaceType co)
1519 toIfaceExpr (Note n e) = IfaceNote (toIfaceNote n) (toIfaceExpr e)
1521 ---------------------
1522 toIfaceNote (SCC cc) = IfaceSCC cc
1523 toIfaceNote InlineMe = IfaceInlineMe
1524 toIfaceNote (CoreNote s) = IfaceCoreNote s
1526 ---------------------
1527 toIfaceBind (NonRec b r) = IfaceNonRec (toIfaceLetBndr b) (toIfaceExpr r)
1528 toIfaceBind (Rec prs) = IfaceRec [(toIfaceLetBndr b, toIfaceExpr r) | (b,r) <- prs]
1530 ---------------------
1531 toIfaceAlt (c,bs,r) = (toIfaceCon c, map getFS bs, toIfaceExpr r)
1533 ---------------------
1534 toIfaceCon (DataAlt dc) | isTupleTyCon tc = IfaceTupleAlt (tupleTyConBoxity tc)
1535 | otherwise = IfaceDataAlt (getName dc)
1537 tc = dataConTyCon dc
1539 toIfaceCon (LitAlt l) = IfaceLitAlt l
1540 toIfaceCon DEFAULT = IfaceDefault
1542 ---------------------
1543 toIfaceApp (App f a) as = toIfaceApp f (a:as)
1544 toIfaceApp (Var v) as
1545 = case isDataConWorkId_maybe v of
1546 -- We convert the *worker* for tuples into IfaceTuples
1547 Just dc | isTupleTyCon tc && saturated
1548 -> IfaceTuple (tupleTyConBoxity tc) tup_args
1550 val_args = dropWhile isTypeArg as
1551 saturated = val_args `lengthIs` idArity v
1552 tup_args = map toIfaceExpr val_args
1553 tc = dataConTyCon dc
1555 other -> mkIfaceApps (toIfaceVar v) as
1557 toIfaceApp e as = mkIfaceApps (toIfaceExpr e) as
1559 mkIfaceApps f as = foldl (\f a -> IfaceApp f (toIfaceExpr a)) f as
1561 ---------------------
1562 toIfaceVar :: Id -> IfaceExpr
1564 | Just fcall <- isFCallId_maybe v = IfaceFCall fcall (toIfaceType (idType v))
1565 -- Foreign calls have special syntax
1566 | isExternalName name = IfaceExt name
1567 | Just (TickBox m ix) <- isTickBoxOp_maybe v
1569 | otherwise = IfaceLcl (getFS name)