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 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.]
186 #include "HsVersions.h"
219 import PackageConfig hiding ( Version )
221 import BasicTypes hiding ( SuccessFlag(..) )
223 import Util hiding ( eqListBy )
236 %************************************************************************
238 \subsection{Completing an interface}
240 %************************************************************************
244 -> Maybe ModIface -- The old interface, if we have it
245 -> ModDetails -- The trimmed, tidied interface
246 -> ModGuts -- Usages, deprecations, etc
247 -> IO (ModIface, -- The new one, complete with decls and versions
248 Bool) -- True <=> there was an old Iface, and the new one
249 -- is identical, so no need to write it
251 mkIface hsc_env maybe_old_iface mod_details
252 ModGuts{ mg_module = this_mod,
254 mg_used_names = used_names,
256 mg_dir_imps = dir_imp_mods,
257 mg_rdr_env = rdr_env,
258 mg_fix_env = fix_env,
259 mg_deprecs = deprecs,
260 mg_hpc_info = hpc_info }
261 = mkIface_ hsc_env maybe_old_iface
262 this_mod is_boot used_names deps rdr_env
263 fix_env deprecs hpc_info dir_imp_mods mod_details
265 -- | make an interface from the results of typechecking only. Useful
266 -- for non-optimising compilation, or where we aren't generating any
267 -- object code at all ('HscNothing').
269 -> Maybe ModIface -- The old interface, if we have it
270 -> ModDetails -- gotten from mkBootModDetails, probably
271 -> TcGblEnv -- Usages, deprecations, etc
274 mkIfaceTc hsc_env maybe_old_iface mod_details
275 tc_result@TcGblEnv{ tcg_mod = this_mod,
277 tcg_imports = imports,
278 tcg_rdr_env = rdr_env,
279 tcg_fix_env = fix_env,
280 tcg_deprecs = deprecs,
281 tcg_hpc = other_hpc_info
284 used_names <- mkUsedNames tc_result
285 deps <- mkDependencies tc_result
286 let hpc_info = emptyHpcInfo other_hpc_info
287 mkIface_ hsc_env maybe_old_iface
288 this_mod (isHsBoot hsc_src) used_names deps rdr_env
289 fix_env deprecs hpc_info (imp_mods imports) mod_details
292 mkUsedNames :: TcGblEnv -> IO NameSet
294 TcGblEnv{ tcg_inst_uses = dfun_uses_var,
298 dfun_uses <- readIORef dfun_uses_var -- What dfuns are used
299 return (allUses dus `unionNameSets` dfun_uses)
301 mkDependencies :: TcGblEnv -> IO Dependencies
303 TcGblEnv{ tcg_mod = mod,
304 tcg_imports = imports,
308 th_used <- readIORef th_var -- Whether TH is used
310 dep_mods = eltsUFM (delFromUFM (imp_dep_mods imports) (moduleName mod))
311 -- M.hi-boot can be in the imp_dep_mods, but we must remove
312 -- it before recording the modules on which this one depends!
313 -- (We want to retain M.hi-boot in imp_dep_mods so that
314 -- loadHiBootInterface can see if M's direct imports depend
315 -- on M.hi-boot, and hence that we should do the hi-boot consistency
318 dir_imp_mods = imp_mods imports
320 -- Modules don't compare lexicographically usually,
321 -- but we want them to do so here.
322 le_mod :: Module -> Module -> Bool
323 le_mod m1 m2 = moduleNameFS (moduleName m1)
324 <= moduleNameFS (moduleName m2)
326 le_dep_mod :: (ModuleName, IsBootInterface)
327 -> (ModuleName, IsBootInterface) -> Bool
328 le_dep_mod (m1,_) (m2,_) = moduleNameFS m1 <= moduleNameFS m2
331 pkgs | th_used = insertList thPackageId (imp_dep_pkgs imports)
332 | otherwise = imp_dep_pkgs imports
334 return Deps { dep_mods = sortLe le_dep_mod dep_mods,
335 dep_pkgs = sortLe (<=) pkgs,
336 dep_orphs = sortLe le_mod (imp_orphs imports),
337 dep_finsts = sortLe le_mod (imp_finsts imports) }
338 -- sort to get into canonical order
341 mkIface_ hsc_env maybe_old_iface
342 this_mod is_boot used_names deps rdr_env fix_env src_deprecs hpc_info
344 ModDetails{ md_insts = insts,
345 md_fam_insts = fam_insts,
347 md_vect_info = vect_info,
349 md_exports = exports }
350 -- NB: notice that mkIface does not look at the bindings
351 -- only at the TypeEnv. The previous Tidy phase has
352 -- put exactly the info into the TypeEnv that we want
353 -- to expose in the interface
355 = do {eps <- hscEPS hsc_env
357 ; usages <- mkUsageInfo hsc_env dir_imp_mods (dep_mods deps) used_names
359 ; let { entities = typeEnvElts type_env ;
360 decls = [ tyThingToIfaceDecl entity
361 | entity <- entities,
362 let name = getName entity,
363 not (isImplicitTyThing entity),
364 -- No implicit Ids and class tycons in the interface file
365 not (isWiredInName name),
366 -- Nor wired-in things; the compiler knows about them anyhow
367 nameIsLocalOrFrom this_mod name ]
368 -- Sigh: see Note [Root-main Id] in TcRnDriver
370 ; fixities = [(occ,fix) | FixItem occ fix <- nameEnvElts fix_env]
371 ; deprecs = src_deprecs
372 ; iface_rules = map (coreRuleToIfaceRule this_mod) rules
373 ; iface_insts = map instanceToIfaceInst insts
374 ; iface_fam_insts = map famInstToIfaceFamInst fam_insts
375 ; iface_vect_info = flattenVectInfo vect_info
377 ; intermediate_iface = ModIface {
378 mi_module = this_mod,
382 mi_exports = mkIfaceExports exports,
384 -- Sort these lexicographically, so that
385 -- the result is stable across compilations
386 mi_insts = sortLe le_inst iface_insts,
387 mi_fam_insts= sortLe le_fam_inst iface_fam_insts,
388 mi_rules = sortLe le_rule iface_rules,
390 mi_vect_info = iface_vect_info,
392 mi_fixities = fixities,
393 mi_deprecs = deprecs,
394 mi_globals = Just rdr_env,
396 -- Left out deliberately: filled in by addVersionInfo
397 mi_mod_vers = initialVersion,
398 mi_exp_vers = initialVersion,
399 mi_rule_vers = initialVersion,
400 mi_orphan = False, -- Always set by addVersionInfo, but
401 -- it's a strict field, so we can't omit it.
402 mi_finsts = False, -- Ditto
403 mi_decls = deliberatelyOmitted "decls",
404 mi_ver_fn = deliberatelyOmitted "ver_fn",
405 mi_hpc = isHpcUsed hpc_info,
407 -- And build the cached values
408 mi_dep_fn = mkIfaceDepCache deprecs,
409 mi_fix_fn = mkIfaceFixCache fixities }
411 -- Add version information
412 ; ext_ver_fn = mkParentVerFun hsc_env eps
413 ; (new_iface, no_change_at_all, pp_diffs, pp_orphs)
414 = {-# SCC "versioninfo" #-}
415 addVersionInfo ext_ver_fn maybe_old_iface
416 intermediate_iface decls
420 ; when (isJust pp_orphs && dopt Opt_WarnOrphans dflags)
421 (printDump (expectJust "mkIface" pp_orphs))
422 ; when (dopt Opt_D_dump_hi_diffs dflags) (printDump pp_diffs)
423 ; dumpIfSet_dyn dflags Opt_D_dump_hi "FINAL INTERFACE"
424 (pprModIface new_iface)
426 -- bug #1617: on reload we weren't updating the PrintUnqualified
427 -- correctly. This stems from the fact that the interface had
428 -- not changed, so addVersionInfo returns the old ModIface
429 -- with the old GlobalRdrEnv (mi_globals).
430 ; let final_iface = new_iface{ mi_globals = Just rdr_env }
432 ; return (final_iface, no_change_at_all) }
434 r1 `le_rule` r2 = ifRuleName r1 <= ifRuleName r2
435 i1 `le_inst` i2 = ifDFun i1 `le_occ` ifDFun i2
436 i1 `le_fam_inst` i2 = ifFamInstTcName i1 `le_occ` ifFamInstTcName i2
438 le_occ :: Name -> Name -> Bool
439 -- Compare lexicographically by OccName, *not* by unique, because
440 -- the latter is not stable across compilations
441 le_occ n1 n2 = nameOccName n1 <= nameOccName n2
443 dflags = hsc_dflags hsc_env
444 deliberatelyOmitted x = panic ("Deliberately omitted: " ++ x)
445 ifFamInstTcName = ifaceTyConName . ifFamInstTyCon
447 flattenVectInfo (VectInfo { vectInfoVar = vVar
448 , vectInfoTyCon = vTyCon
451 ifaceVectInfoVar = [ Var.varName v
452 | (v, _) <- varEnvElts vVar],
453 ifaceVectInfoTyCon = [ tyConName t
454 | (t, t_v) <- nameEnvElts vTyCon
456 ifaceVectInfoTyConReuse = [ tyConName t
457 | (t, t_v) <- nameEnvElts vTyCon
461 -----------------------------
462 writeIfaceFile :: DynFlags -> ModLocation -> ModIface -> IO ()
463 writeIfaceFile dflags location new_iface
464 = do createDirectoryHierarchy (directoryOf hi_file_path)
465 writeBinIface dflags hi_file_path new_iface
466 where hi_file_path = ml_hi_file location
469 -- -----------------------------------------------------------------------------
470 -- Look up parents and versions of Names
472 -- This is like a global version of the mi_ver_fn field in each ModIface.
473 -- Given a Name, it finds the ModIface, and then uses mi_ver_fn to get
474 -- the parent and version info.
477 :: HscEnv -- needed to look up versions
478 -> ExternalPackageState -- ditto
479 -> (Name -> (OccName,Version))
480 mkParentVerFun hsc_env eps
483 mod = nameModule name
484 occ = nameOccName name
485 iface = lookupIfaceByModule (hsc_dflags hsc_env) hpt pit mod `orElse`
486 pprPanic "lookupVers2" (ppr mod <+> ppr occ)
488 mi_ver_fn iface occ `orElse`
489 pprPanic "lookupVers1" (ppr mod <+> ppr occ)
491 hpt = hsc_HPT hsc_env
494 -----------------------------------------------------------------------------
495 -- Compute version numbers for local decls
498 :: (Name -> (OccName,Version)) -- lookup parents and versions of names
499 -> Maybe ModIface -- The old interface, read from M.hi
500 -> ModIface -- The new interface (lacking decls)
501 -> [IfaceDecl] -- The new decls
502 -> (ModIface, -- Updated interface
503 Bool, -- True <=> no changes at all; no need to write Iface
505 Maybe SDoc) -- Warnings about orphans
507 addVersionInfo ver_fn Nothing new_iface new_decls
508 -- No old interface, so definitely write a new one!
509 = (new_iface { mi_orphan = not (null orph_insts && null orph_rules)
510 , mi_finsts = not . null $ mi_fam_insts new_iface
511 , mi_decls = [(initialVersion, decl) | decl <- new_decls]
512 , mi_ver_fn = mkIfaceVerCache (zip (repeat initialVersion)
516 ptext SLIT("No old interface file"),
517 pprOrphans orph_insts orph_rules)
519 orph_insts = filter (isNothing . ifInstOrph) (mi_insts new_iface)
520 orph_rules = filter (isNothing . ifRuleOrph) (mi_rules new_iface)
522 addVersionInfo ver_fn (Just old_iface@(ModIface {
523 mi_mod_vers = old_mod_vers,
524 mi_exp_vers = old_exp_vers,
525 mi_rule_vers = old_rule_vers,
526 mi_decls = old_decls,
527 mi_ver_fn = old_decl_vers,
528 mi_fix_fn = old_fixities }))
529 new_iface@(ModIface { mi_fix_fn = new_fixities })
532 = (old_iface, True, ptext SLIT("Interface file unchanged"), pp_orphs)
534 = (final_iface, False, vcat [ptext SLIT("Interface file has changed"),
535 nest 2 pp_diffs], pp_orphs)
537 final_iface = new_iface {
538 mi_mod_vers = bump_unless no_output_change old_mod_vers,
539 mi_exp_vers = bump_unless no_export_change old_exp_vers,
540 mi_rule_vers = bump_unless no_rule_change old_rule_vers,
541 mi_orphan = not (null new_orph_rules && null new_orph_insts),
542 mi_finsts = not . null $ mi_fam_insts new_iface,
543 mi_decls = decls_w_vers,
544 mi_ver_fn = mkIfaceVerCache decls_w_vers }
546 decls_w_vers = [(add_vers decl, decl) | decl <- new_decls]
549 (old_non_orph_insts, old_orph_insts) =
550 mkOrphMap ifInstOrph (mi_insts old_iface)
551 (new_non_orph_insts, new_orph_insts) =
552 mkOrphMap ifInstOrph (mi_insts new_iface)
553 old_fam_insts = mi_fam_insts old_iface
554 new_fam_insts = mi_fam_insts new_iface
555 same_insts occ = eqMaybeBy (eqListBy eqIfInst)
556 (lookupOccEnv old_non_orph_insts occ)
557 (lookupOccEnv new_non_orph_insts occ)
559 (old_non_orph_rules, old_orph_rules) =
560 mkOrphMap ifRuleOrph (mi_rules old_iface)
561 (new_non_orph_rules, new_orph_rules) =
562 mkOrphMap ifRuleOrph (mi_rules new_iface)
563 same_rules occ = eqMaybeBy (eqListBy eqIfRule)
564 (lookupOccEnv old_non_orph_rules occ)
565 (lookupOccEnv new_non_orph_rules occ)
567 -- Computing what changed
568 no_output_change = no_decl_change && no_rule_change &&
569 no_export_change && no_deprec_change
570 no_export_change = mi_exports new_iface == mi_exports old_iface
572 no_decl_change = isEmptyOccSet changed_occs
573 no_rule_change = not (changedWrtNames changed_occs (eqListBy eqIfRule old_orph_rules new_orph_rules)
574 || changedWrtNames changed_occs (eqListBy eqIfInst old_orph_insts new_orph_insts)
575 || changedWrtNames changed_occs (eqListBy eqIfFamInst old_fam_insts new_fam_insts))
576 no_deprec_change = mi_deprecs new_iface == mi_deprecs old_iface
578 -- If the usages havn't changed either, we don't need to write the interface file
579 no_other_changes = mi_usages new_iface == mi_usages old_iface &&
580 mi_deps new_iface == mi_deps old_iface &&
581 mi_hpc new_iface == mi_hpc old_iface
582 no_change_at_all = no_output_change && no_other_changes
584 pp_diffs = vcat [pp_change no_export_change "Export list"
585 (ppr old_exp_vers <+> arrow <+> ppr (mi_exp_vers final_iface)),
586 pp_change no_rule_change "Rules"
587 (ppr old_rule_vers <+> arrow <+> ppr (mi_rule_vers final_iface)),
588 pp_change no_deprec_change "Deprecations" empty,
589 pp_change no_other_changes "Usages" empty,
591 pp_change True what info = empty
592 pp_change False what info = text what <+> ptext SLIT("changed") <+> info
595 old_decl_env = mkOccEnv [(ifName decl, decl) | (_,decl) <- old_decls]
596 same_fixity n = bool (old_fixities n == new_fixities n)
599 -- Adding version info
600 new_version = bumpVersion old_mod_vers
601 -- Start from the old module version, not from
602 -- zero so that if you remove f, and then add
603 -- it again, you don't thereby reduce f's
606 add_vers decl | occ `elemOccSet` changed_occs = new_version
607 | otherwise = snd (expectJust "add_vers" (old_decl_vers occ))
608 -- If it's unchanged, there jolly well
609 where -- should be an old version number
613 -- Deciding which declarations have changed
615 -- For each local decl, the IfaceEq gives the list of things that
616 -- must be unchanged for the declaration as a whole to be unchanged.
617 eq_info :: [(OccName, IfaceEq)]
618 eq_info = map check_eq new_decls
620 | Just old_decl <- lookupOccEnv old_decl_env occ
621 = (occ, new_decl `eqIfDecl` old_decl &&& eq_indirects new_decl)
622 | otherwise {- No corresponding old decl -}
625 occ = ifName new_decl
627 eq_indirects :: IfaceDecl -> IfaceEq
628 -- When seeing if two decls are the same, remember to
629 -- check whether any relevant fixity or rules have changed
630 eq_indirects (IfaceId {ifName = occ}) = eq_ind_occ occ
631 eq_indirects (IfaceClass {ifName = cls_occ, ifSigs = sigs})
632 = same_insts cls_occ &&&
633 eq_ind_occs [op | IfaceClassOp op _ _ <- sigs]
634 eq_indirects (IfaceData {ifName = tc_occ, ifCons = cons})
635 = same_insts tc_occ &&& same_fixity tc_occ &&& -- The TyCon can have a fixity too
636 eq_ind_occs (map ifConOcc (visibleIfConDecls cons))
637 eq_indirects other = Equal -- Synonyms and foreign declarations
639 eq_ind_occ :: OccName -> IfaceEq -- For class ops and Ids; check fixity and rules
640 eq_ind_occ occ = same_fixity occ &&& same_rules occ
641 eq_ind_occs = foldr ((&&&) . eq_ind_occ) Equal
643 -- The Occs of declarations that changed.
644 changed_occs :: OccSet
645 changed_occs = computeChangedOccs ver_fn (mi_module new_iface)
646 (mi_usages old_iface) eq_info
650 pp_decl_diffs :: SDoc -- Nothing => no changes
652 | isEmptyOccSet changed_occs = empty
654 = vcat [ptext SLIT("Changed occs:") <+> ppr (occSetElts changed_occs),
655 ptext SLIT("Version change for these decls:"),
656 nest 2 (vcat (map show_change new_decls))]
658 eq_env = mkOccEnv eq_info
660 | not (occ `elemOccSet` changed_occs) = empty
662 = vcat [ppr occ <+> ppr (old_decl_vers occ) <+> arrow <+> ppr new_version,
665 occ = ifName new_decl
666 why = case lookupOccEnv eq_env occ of
667 Just (EqBut names) -> sep [ppr occ <> colon, ptext SLIT("Free vars (only) changed:") <> ppr names,
668 nest 2 (braces (fsep (map ppr (occSetElts
669 (occs `intersectOccSet` changed_occs)))))]
670 where occs = mkOccSet (map nameOccName (nameSetToList names))
672 | Just old_decl <- lookupOccEnv old_decl_env occ
673 -> vcat [ptext SLIT("Old:") <+> ppr old_decl,
674 ptext SLIT("New:") <+> ppr new_decl]
676 -> ppr occ <+> ptext SLIT("only in new interface")
677 other -> pprPanic "MkIface.show_change" (ppr occ)
679 pp_orphs = pprOrphans new_orph_insts new_orph_rules
682 pprOrphans insts rules
683 | null insts && null rules = Nothing
686 if null insts then empty else
687 hang (ptext SLIT("Warning: orphan instances:"))
688 2 (vcat (map ppr insts)),
689 if null rules then empty else
690 hang (ptext SLIT("Warning: orphan rules:"))
691 2 (vcat (map ppr rules))
695 :: (Name -> (OccName,Version)) -- get parents and versions
696 -> Module -- This module
697 -> [Usage] -- Usages from old iface
698 -> [(OccName, IfaceEq)] -- decl names, equality conditions
699 -> OccSet -- set of things that have changed
700 computeChangedOccs ver_fn this_module old_usages eq_info
701 = foldl add_changes emptyOccSet (stronglyConnComp edges)
704 -- return True if an external name has changed
705 name_changed :: Name -> Bool
707 | Just ents <- lookupUFM usg_modmap (moduleName mod),
708 Just v <- lookupUFM ents parent_occ
710 | modulePackageId mod == this_pkg
711 = WARN(True, ptext SLIT("computeChangedOccs") <+> ppr nm) True
712 -- should really be a panic, see #1959. The problem is that the usages doesn't
713 -- contain all the names that might be referred to by unfoldings. So as a
714 -- conservative workaround we just assume these names have changed.
715 | otherwise = False -- must be in another package
718 (parent_occ, new_version) = ver_fn nm
720 this_pkg = modulePackageId this_module
722 -- Turn the usages from the old ModIface into a mapping
723 usg_modmap = listToUFM [ (usg_name usg, listToUFM (usg_entities usg))
724 | usg <- old_usages ]
726 get_local_eq_info :: GenIfaceEq NameSet -> GenIfaceEq OccSet
727 get_local_eq_info Equal = Equal
728 get_local_eq_info NotEqual = NotEqual
729 get_local_eq_info (EqBut ns) = foldNameSet f Equal ns
730 where f name eq | nameModule name == this_module =
731 EqBut (unitOccSet (nameOccName name)) `and_occifeq` eq
732 | name_changed name = NotEqual
735 local_eq_infos = mapSnd get_local_eq_info eq_info
737 edges :: [((OccName, OccIfaceEq), Unique, [Unique])]
738 edges = [ (node, getUnique occ, map getUnique occs)
739 | node@(occ, iface_eq) <- local_eq_infos
740 , let occs = case iface_eq of
741 EqBut occ_set -> occSetElts occ_set
744 -- Changes in declarations
745 add_changes :: OccSet -> SCC (OccName, OccIfaceEq) -> OccSet
746 add_changes so_far (AcyclicSCC (occ, iface_eq))
747 | changedWrt so_far iface_eq -- This one has changed
748 = extendOccSet so_far occ
749 add_changes so_far (CyclicSCC pairs)
750 | changedWrt so_far (foldr1 and_occifeq iface_eqs)
751 -- One of this group has changed
752 = extendOccSetList so_far occs
753 where (occs, iface_eqs) = unzip pairs
754 add_changes so_far other = so_far
756 type OccIfaceEq = GenIfaceEq OccSet
758 changedWrt :: OccSet -> OccIfaceEq -> Bool
759 changedWrt so_far Equal = False
760 changedWrt so_far NotEqual = True
761 changedWrt so_far (EqBut kids) = so_far `intersectsOccSet` kids
763 changedWrtNames :: OccSet -> IfaceEq -> Bool
764 changedWrtNames so_far Equal = False
765 changedWrtNames so_far NotEqual = True
766 changedWrtNames so_far (EqBut kids) =
767 so_far `intersectsOccSet` mkOccSet (map nameOccName (nameSetToList kids))
769 and_occifeq :: OccIfaceEq -> OccIfaceEq -> OccIfaceEq
770 Equal `and_occifeq` x = x
771 NotEqual `and_occifeq` x = NotEqual
772 EqBut nms `and_occifeq` Equal = EqBut nms
773 EqBut nms `and_occifeq` NotEqual = NotEqual
774 EqBut nms1 `and_occifeq` EqBut nms2 = EqBut (nms1 `unionOccSets` nms2)
776 ----------------------
777 -- mkOrphMap partitions instance decls or rules into
778 -- (a) an OccEnv for ones that are not orphans,
779 -- mapping the local OccName to a list of its decls
780 -- (b) a list of orphan decls
781 mkOrphMap :: (decl -> Maybe OccName) -- (Just occ) for a non-orphan decl, keyed by occ
782 -- Nothing for an orphan decl
783 -> [decl] -- Sorted into canonical order
784 -> (OccEnv [decl], -- Non-orphan decls associated with their key;
785 -- each sublist in canonical order
786 [decl]) -- Orphan decls; in canonical order
787 mkOrphMap get_key decls
788 = foldl go (emptyOccEnv, []) decls
790 go (non_orphs, orphs) d
791 | Just occ <- get_key d
792 = (extendOccEnv_C (\ ds _ -> d:ds) non_orphs occ [d], orphs)
793 | otherwise = (non_orphs, d:orphs)
795 ----------------------
796 bump_unless :: Bool -> Version -> Version
797 bump_unless True v = v -- True <=> no change
798 bump_unless False v = bumpVersion v
802 %*********************************************************
804 \subsection{Keeping track of what we've slurped, and version numbers}
806 %*********************************************************
810 mkUsageInfo :: HscEnv
811 -> ModuleEnv (Module, [(ModuleName, Bool, SrcSpan)])
812 -> [(ModuleName, IsBootInterface)]
813 -> NameSet -> IO [Usage]
814 mkUsageInfo hsc_env dir_imp_mods dep_mods used_names
815 = do { eps <- hscEPS hsc_env
816 ; let usages = mk_usage_info (eps_PIT eps) hsc_env
817 dir_imp_mods dep_mods used_names
818 ; usages `seqList` return usages }
819 -- seq the list of Usages returned: occasionally these
820 -- don't get evaluated for a while and we can end up hanging on to
821 -- the entire collection of Ifaces.
823 mk_usage_info :: PackageIfaceTable
825 -> ModuleEnv (Module, [(ModuleName, Bool, SrcSpan)])
826 -> [(ModuleName, IsBootInterface)]
829 mk_usage_info pit hsc_env dir_imp_mods dep_mods used_names
830 = mapCatMaybes mkUsage dep_mods
831 -- ToDo: do we need to sort into canonical order?
833 hpt = hsc_HPT hsc_env
834 dflags = hsc_dflags hsc_env
836 -- ent_map groups together all the things imported and used
837 -- from a particular module in this package
838 ent_map :: ModuleEnv [OccName]
839 ent_map = foldNameSet add_mv emptyModuleEnv used_names
841 | isWiredInName name = mv_map -- ignore wired-in names
843 = case nameModule_maybe name of
844 Nothing -> mv_map -- ignore internal names
845 Just mod -> extendModuleEnv_C add_item mv_map mod [occ]
847 occ = nameOccName name
848 add_item occs _ = occ:occs
850 depend_on_exports mod = case lookupModuleEnv dir_imp_mods mod of
851 Just (_, xs) -> any (\(_, no_imp, _) -> not no_imp) xs
854 -- We want to create a Usage for a home module if
855 -- a) we used something from; has something in used_names
856 -- b) we imported all of it, even if we used nothing from it
857 -- (need to recompile if its export list changes: export_vers)
858 -- c) is a home-package orphan or family-instance module (need to
859 -- recompile if its instance decls change: rules_vers)
860 mkUsage :: (ModuleName, IsBootInterface) -> Maybe Usage
861 mkUsage (mod_name, _)
862 | isNothing maybe_iface -- We can't depend on it if we didn't
863 || (null used_occs -- load its interface.
864 && isNothing export_vers
867 = Nothing -- Record no usage info
870 = Just (Usage { usg_name = mod_name,
872 usg_exports = export_vers,
873 usg_entities = fmToList ent_vers,
874 usg_rules = rules_vers })
876 maybe_iface = lookupIfaceByModule dflags hpt pit mod
877 -- In one-shot mode, the interfaces for home-package
878 -- modules accumulate in the PIT not HPT. Sigh.
880 mod = mkModule (thisPackage dflags) mod_name
882 Just iface = maybe_iface
883 orphan_mod = mi_orphan iface
884 finsts_mod = mi_finsts iface
885 version_env = mi_ver_fn iface
886 mod_vers = mi_mod_vers iface
887 rules_vers = mi_rule_vers iface
888 export_vers | depend_on_exports mod = Just (mi_exp_vers iface)
889 | otherwise = Nothing
891 used_occs = lookupModuleEnv ent_map mod `orElse` []
893 -- Making a FiniteMap here ensures that (a) we remove duplicates
894 -- when we have usages on several subordinates of a single parent,
895 -- and (b) that the usages emerge in a canonical order, which
896 -- is why we use FiniteMap rather than OccEnv: FiniteMap works
897 -- using Ord on the OccNames, which is a lexicographic ordering.
898 ent_vers :: FiniteMap OccName Version
899 ent_vers = listToFM (map lookup_occ used_occs)
902 case version_env occ of
903 Nothing -> pprTrace "hmm, strange" (ppr mod <+> ppr occ) $
904 (occ, initialVersion) -- does this ever happen?
905 Just (parent, version) -> (parent, version)
909 mkIfaceExports :: [AvailInfo]
910 -> [(Module, [GenAvailInfo OccName])]
911 -- Group by module and sort by occurrence
912 -- This keeps the list in canonical order
913 mkIfaceExports exports
914 = [ (mod, eltsFM avails)
915 | (mod, avails) <- fmToList groupFM
918 -- Group by the module where the exported entities are defined
919 -- (which may not be the same for all Names in an Avail)
920 -- Deliberately use FiniteMap rather than UniqFM so we
921 -- get a canonical ordering
922 groupFM :: ModuleEnv (FiniteMap FastString (GenAvailInfo OccName))
923 groupFM = foldl add emptyModuleEnv exports
925 add_one :: ModuleEnv (FiniteMap FastString (GenAvailInfo OccName))
926 -> Module -> GenAvailInfo OccName
927 -> ModuleEnv (FiniteMap FastString (GenAvailInfo OccName))
928 add_one env mod avail
929 = extendModuleEnv_C plusFM env mod
930 (unitFM (occNameFS (availName avail)) avail)
932 -- NB: we should not get T(X) and T(Y) in the export list
933 -- else the plusFM will simply discard one! They
934 -- should have been combined by now.
936 = add_one env (nameModule n) (Avail (nameOccName n))
938 add env (AvailTC tc ns)
939 = foldl add_for_mod env mods
941 tc_occ = nameOccName tc
942 mods = nub (map nameModule ns)
943 -- Usually just one, but see Note [Original module]
946 = add_one env mod (AvailTC tc_occ (sort names_from_mod))
947 -- NB. sort the children, we need a canonical order
949 names_from_mod = [nameOccName n | n <- ns, nameModule n == mod]
952 Note [Orignal module]
953 ~~~~~~~~~~~~~~~~~~~~~
955 module X where { data family T }
956 module Y( T(..) ) where { import X; data instance T Int = MkT Int }
957 The exported Avail from Y will look like
960 - only MkT is brought into scope by the data instance;
961 - but the parent (used for grouping and naming in T(..) exports) is X.T
962 - and in this case we export X.T too
964 In the result of MkIfaceExports, the names are grouped by defining module,
965 so we may need to split up a single Avail into multiple ones.
968 %************************************************************************
970 Load the old interface file for this module (unless
971 we have it aleady), and check whether it is up to date
974 %************************************************************************
977 checkOldIface :: HscEnv
979 -> Bool -- Source unchanged
980 -> Maybe ModIface -- Old interface from compilation manager, if any
981 -> IO (RecompileRequired, Maybe ModIface)
983 checkOldIface hsc_env mod_summary source_unchanged maybe_iface
984 = do { showPass (hsc_dflags hsc_env)
985 ("Checking old interface for " ++
986 showSDoc (ppr (ms_mod mod_summary))) ;
988 ; initIfaceCheck hsc_env $
989 check_old_iface hsc_env mod_summary source_unchanged maybe_iface
992 check_old_iface hsc_env mod_summary source_unchanged maybe_iface
993 = do -- CHECK WHETHER THE SOURCE HAS CHANGED
994 { ifM (not source_unchanged)
995 (traceHiDiffs (nest 4 (text "Source file changed or recompilation check turned off")))
997 -- If the source has changed and we're in interactive mode, avoid reading
998 -- an interface; just return the one we might have been supplied with.
999 ; let dflags = hsc_dflags hsc_env
1000 ; if not (isObjectTarget (hscTarget dflags)) && not source_unchanged then
1001 return (outOfDate, maybe_iface)
1003 case maybe_iface of {
1004 Just old_iface -> do -- Use the one we already have
1005 { traceIf (text "We already have the old interface for" <+> ppr (ms_mod mod_summary))
1006 ; recomp <- checkVersions hsc_env source_unchanged mod_summary old_iface
1007 ; return (recomp, Just old_iface) }
1011 -- Try and read the old interface for the current module
1012 -- from the .hi file left from the last time we compiled it
1013 { let iface_path = msHiFilePath mod_summary
1014 ; read_result <- readIface (ms_mod mod_summary) iface_path False
1015 ; case read_result of {
1016 Failed err -> do -- Old interface file not found, or garbled; give up
1017 { traceIf (text "FYI: cannot read old interface file:"
1019 ; return (outOfDate, Nothing) }
1021 ; Succeeded iface -> do
1023 -- We have got the old iface; check its versions
1024 { traceIf (text "Read the interface file" <+> text iface_path)
1025 ; recomp <- checkVersions hsc_env source_unchanged mod_summary iface
1026 ; returnM (recomp, Just iface)
1031 @recompileRequired@ is called from the HscMain. It checks whether
1032 a recompilation is required. It needs access to the persistent state,
1033 finder, etc, because it may have to load lots of interface files to
1034 check their versions.
1037 type RecompileRequired = Bool
1038 upToDate = False -- Recompile not required
1039 outOfDate = True -- Recompile required
1041 checkVersions :: HscEnv
1042 -> Bool -- True <=> source unchanged
1044 -> ModIface -- Old interface
1045 -> IfG RecompileRequired
1046 checkVersions hsc_env source_unchanged mod_summary iface
1047 | not source_unchanged
1050 = do { traceHiDiffs (text "Considering whether compilation is required for" <+>
1051 ppr (mi_module iface) <> colon)
1053 ; recomp <- checkDependencies hsc_env mod_summary iface
1054 ; if recomp then return outOfDate else do {
1056 -- Source code unchanged and no errors yet... carry on
1058 -- First put the dependent-module info, read from the old interface, into the envt,
1059 -- so that when we look for interfaces we look for the right one (.hi or .hi-boot)
1061 -- It's just temporary because either the usage check will succeed
1062 -- (in which case we are done with this module) or it'll fail (in which
1063 -- case we'll compile the module from scratch anyhow).
1065 -- We do this regardless of compilation mode, although in --make mode
1066 -- all the dependent modules should be in the HPT already, so it's
1068 updateEps_ $ \eps -> eps { eps_is_boot = mod_deps }
1070 ; let this_pkg = thisPackage (hsc_dflags hsc_env)
1071 ; checkList [checkModUsage this_pkg u | u <- mi_usages iface]
1074 -- This is a bit of a hack really
1075 mod_deps :: ModuleNameEnv (ModuleName, IsBootInterface)
1076 mod_deps = mkModDeps (dep_mods (mi_deps iface))
1079 -- If the direct imports of this module are resolved to targets that
1080 -- are not among the dependencies of the previous interface file,
1081 -- then we definitely need to recompile. This catches cases like
1082 -- - an exposed package has been upgraded
1083 -- - we are compiling with different package flags
1084 -- - a home module that was shadowing a package module has been removed
1085 -- - a new home module has been added that shadows a package module
1088 -- Returns True if recompilation is required.
1089 checkDependencies :: HscEnv -> ModSummary -> ModIface -> IfG RecompileRequired
1090 checkDependencies hsc_env summary iface
1091 = orM (map dep_missing (ms_imps summary ++ ms_srcimps summary))
1093 prev_dep_mods = dep_mods (mi_deps iface)
1094 prev_dep_pkgs = dep_pkgs (mi_deps iface)
1096 this_pkg = thisPackage (hsc_dflags hsc_env)
1098 orM = foldr f (return False)
1099 where f m rest = do b <- m; if b then return True else rest
1101 dep_missing (L _ mod) = do
1102 find_res <- ioToIOEnv $ findImportedModule hsc_env mod Nothing
1106 -> if moduleName mod `notElem` map fst prev_dep_mods
1107 then do traceHiDiffs $
1108 text "imported module " <> quotes (ppr mod) <>
1109 text " not among previous dependencies"
1114 -> if pkg `notElem` prev_dep_pkgs
1115 then do traceHiDiffs $
1116 text "imported module " <> quotes (ppr mod) <>
1117 text " is from package " <> quotes (ppr pkg) <>
1118 text ", which is not among previous dependencies"
1122 where pkg = modulePackageId mod
1123 _otherwise -> return outOfDate
1125 checkModUsage :: PackageId ->Usage -> IfG RecompileRequired
1126 -- Given the usage information extracted from the old
1127 -- M.hi file for the module being compiled, figure out
1128 -- whether M needs to be recompiled.
1130 checkModUsage this_pkg (Usage { usg_name = mod_name, usg_mod = old_mod_vers,
1131 usg_rules = old_rule_vers,
1132 usg_exports = maybe_old_export_vers,
1133 usg_entities = old_decl_vers })
1134 = -- Load the imported interface is possible
1136 doc_str = sep [ptext SLIT("need version info for"), ppr mod_name]
1138 traceHiDiffs (text "Checking usages for module" <+> ppr mod_name) `thenM_`
1141 mod = mkModule this_pkg mod_name
1143 loadInterface doc_str mod ImportBySystem `thenM` \ mb_iface ->
1144 -- Load the interface, but don't complain on failure;
1145 -- Instead, get an Either back which we can test
1148 Failed exn -> (out_of_date (sep [ptext SLIT("Can't find version number for module"),
1150 -- Couldn't find or parse a module mentioned in the
1151 -- old interface file. Don't complain -- it might just be that
1152 -- the current module doesn't need that import and it's been deleted
1156 new_mod_vers = mi_mod_vers iface
1157 new_decl_vers = mi_ver_fn iface
1158 new_export_vers = mi_exp_vers iface
1159 new_rule_vers = mi_rule_vers iface
1162 checkModuleVersion old_mod_vers new_mod_vers `thenM` \ recompile ->
1163 if not recompile then
1167 -- CHECK EXPORT LIST
1168 if checkExportList maybe_old_export_vers new_export_vers then
1169 out_of_date_vers (ptext SLIT(" Export list changed"))
1170 (expectJust "checkModUsage" maybe_old_export_vers)
1175 if old_rule_vers /= new_rule_vers then
1176 out_of_date_vers (ptext SLIT(" Rules changed"))
1177 old_rule_vers new_rule_vers
1180 -- CHECK ITEMS ONE BY ONE
1181 checkList [checkEntityUsage new_decl_vers u | u <- old_decl_vers] `thenM` \ recompile ->
1183 returnM outOfDate -- This one failed, so just bail out now
1185 up_to_date (ptext SLIT(" Great! The bits I use are up to date"))
1188 ------------------------
1189 checkModuleVersion old_mod_vers new_mod_vers
1190 | new_mod_vers == old_mod_vers
1191 = up_to_date (ptext SLIT("Module version unchanged"))
1194 = out_of_date_vers (ptext SLIT(" Module version has changed"))
1195 old_mod_vers new_mod_vers
1197 ------------------------
1198 checkExportList Nothing new_vers = upToDate
1199 checkExportList (Just v) new_vers = v /= new_vers
1201 ------------------------
1202 checkEntityUsage new_vers (name,old_vers)
1203 = case new_vers name of
1205 Nothing -> -- We used it before, but it ain't there now
1206 out_of_date (sep [ptext SLIT("No longer exported:"), ppr name])
1208 Just (_, new_vers) -- It's there, but is it up to date?
1209 | new_vers == old_vers -> traceHiDiffs (text " Up to date" <+> ppr name <+> parens (ppr new_vers)) `thenM_`
1211 | otherwise -> out_of_date_vers (ptext SLIT(" Out of date:") <+> ppr name)
1214 up_to_date msg = traceHiDiffs msg `thenM_` returnM upToDate
1215 out_of_date msg = traceHiDiffs msg `thenM_` returnM outOfDate
1216 out_of_date_vers msg old_vers new_vers
1217 = out_of_date (hsep [msg, ppr old_vers, ptext SLIT("->"), ppr new_vers])
1219 ----------------------
1220 checkList :: [IfG RecompileRequired] -> IfG RecompileRequired
1221 -- This helper is used in two places
1222 checkList [] = returnM upToDate
1223 checkList (check:checks) = check `thenM` \ recompile ->
1230 %************************************************************************
1232 Converting things to their Iface equivalents
1234 %************************************************************************
1237 tyThingToIfaceDecl :: TyThing -> IfaceDecl
1238 -- Assumption: the thing is already tidied, so that locally-bound names
1239 -- (lambdas, for-alls) already have non-clashing OccNames
1240 -- Reason: Iface stuff uses OccNames, and the conversion here does
1241 -- not do tidying on the way
1242 tyThingToIfaceDecl (AnId id)
1243 = IfaceId { ifName = getOccName id,
1244 ifType = toIfaceType (idType id),
1247 info = case toIfaceIdInfo (idInfo id) of
1249 items -> HasInfo items
1251 tyThingToIfaceDecl (AClass clas)
1252 = IfaceClass { ifCtxt = toIfaceContext sc_theta,
1253 ifName = getOccName clas,
1254 ifTyVars = toIfaceTvBndrs clas_tyvars,
1255 ifFDs = map toIfaceFD clas_fds,
1256 ifATs = map (tyThingToIfaceDecl . ATyCon) clas_ats,
1257 ifSigs = map toIfaceClassOp op_stuff,
1258 ifRec = boolToRecFlag (isRecursiveTyCon tycon) }
1260 (clas_tyvars, clas_fds, sc_theta, _, clas_ats, op_stuff)
1261 = classExtraBigSig clas
1262 tycon = classTyCon clas
1264 toIfaceClassOp (sel_id, def_meth)
1265 = ASSERT(sel_tyvars == clas_tyvars)
1266 IfaceClassOp (getOccName sel_id) def_meth (toIfaceType op_ty)
1268 -- Be careful when splitting the type, because of things
1269 -- like class Foo a where
1270 -- op :: (?x :: String) => a -> a
1271 -- and class Baz a where
1272 -- op :: (Ord a) => a -> a
1273 (sel_tyvars, rho_ty) = splitForAllTys (idType sel_id)
1274 op_ty = funResultTy rho_ty
1276 toIfaceFD (tvs1, tvs2) = (map getFS tvs1, map getFS tvs2)
1278 tyThingToIfaceDecl (ATyCon tycon)
1280 = IfaceSyn { ifName = getOccName tycon,
1281 ifTyVars = toIfaceTvBndrs tyvars,
1282 ifOpenSyn = syn_isOpen,
1283 ifSynRhs = toIfaceType syn_tyki,
1284 ifFamInst = famInstToIface (tyConFamInst_maybe tycon)
1288 = IfaceData { ifName = getOccName tycon,
1289 ifTyVars = toIfaceTvBndrs tyvars,
1290 ifCtxt = toIfaceContext (tyConStupidTheta tycon),
1291 ifCons = ifaceConDecls (algTyConRhs tycon),
1292 ifRec = boolToRecFlag (isRecursiveTyCon tycon),
1293 ifGadtSyntax = isGadtSyntaxTyCon tycon,
1294 ifGeneric = tyConHasGenerics tycon,
1295 ifFamInst = famInstToIface (tyConFamInst_maybe tycon)}
1297 | isForeignTyCon tycon
1298 = IfaceForeign { ifName = getOccName tycon,
1299 ifExtName = tyConExtName tycon }
1301 | otherwise = pprPanic "toIfaceDecl" (ppr tycon)
1303 tyvars = tyConTyVars tycon
1304 (syn_isOpen, syn_tyki) = case synTyConRhs tycon of
1305 OpenSynTyCon ki _ -> (True , ki)
1306 SynonymTyCon ty -> (False, ty)
1308 ifaceConDecls (NewTyCon { data_con = con }) =
1309 IfNewTyCon (ifaceConDecl con)
1310 ifaceConDecls (DataTyCon { data_cons = cons }) =
1311 IfDataTyCon (map ifaceConDecl cons)
1312 ifaceConDecls OpenTyCon {} = IfOpenDataTyCon
1313 ifaceConDecls AbstractTyCon = IfAbstractTyCon
1314 -- The last case happens when a TyCon has been trimmed during tidying
1315 -- Furthermore, tyThingToIfaceDecl is also used
1316 -- in TcRnDriver for GHCi, when browsing a module, in which case the
1317 -- AbstractTyCon case is perfectly sensible.
1319 ifaceConDecl data_con
1320 = IfCon { ifConOcc = getOccName (dataConName data_con),
1321 ifConInfix = dataConIsInfix data_con,
1322 ifConUnivTvs = toIfaceTvBndrs (dataConUnivTyVars data_con),
1323 ifConExTvs = toIfaceTvBndrs (dataConExTyVars data_con),
1324 ifConEqSpec = to_eq_spec (dataConEqSpec data_con),
1325 ifConCtxt = toIfaceContext (dataConEqTheta data_con ++ dataConDictTheta data_con),
1326 ifConArgTys = map toIfaceType (dataConOrigArgTys data_con),
1327 ifConFields = map getOccName
1328 (dataConFieldLabels data_con),
1329 ifConStricts = dataConStrictMarks data_con }
1331 to_eq_spec spec = [(getOccName tv, toIfaceType ty) | (tv,ty) <- spec]
1333 famInstToIface Nothing = Nothing
1334 famInstToIface (Just (famTyCon, instTys)) =
1335 Just (toIfaceTyCon famTyCon, map toIfaceType instTys)
1337 tyThingToIfaceDecl (ADataCon dc)
1338 = pprPanic "toIfaceDecl" (ppr dc) -- Should be trimmed out earlier
1341 getFS x = occNameFS (getOccName x)
1343 --------------------------
1344 instanceToIfaceInst :: Instance -> IfaceInst
1345 instanceToIfaceInst ispec@(Instance { is_dfun = dfun_id, is_flag = oflag,
1346 is_cls = cls_name, is_tcs = mb_tcs })
1347 = ASSERT( cls_name == className cls )
1348 IfaceInst { ifDFun = dfun_name,
1350 ifInstCls = cls_name,
1351 ifInstTys = map do_rough mb_tcs,
1354 do_rough Nothing = Nothing
1355 do_rough (Just n) = Just (toIfaceTyCon_name n)
1357 dfun_name = idName dfun_id
1358 mod = nameModule dfun_name
1359 is_local name = nameIsLocalOrFrom mod name
1361 -- Compute orphanhood. See Note [Orphans] in IfaceSyn
1362 (_, _, cls, tys) = tcSplitDFunTy (idType dfun_id)
1363 -- Slightly awkward: we need the Class to get the fundeps
1364 (tvs, fds) = classTvsFds cls
1365 arg_names = [filterNameSet is_local (tyClsNamesOfType ty) | ty <- tys]
1366 orph | is_local cls_name = Just (nameOccName cls_name)
1367 | all isJust mb_ns = head mb_ns
1368 | otherwise = Nothing
1370 mb_ns :: [Maybe OccName] -- One for each fundep; a locally-defined name
1371 -- that is not in the "determined" arguments
1372 mb_ns | null fds = [choose_one arg_names]
1373 | otherwise = map do_one fds
1374 do_one (ltvs,rtvs) = choose_one [ns | (tv,ns) <- tvs `zip` arg_names
1375 , not (tv `elem` rtvs)]
1377 choose_one :: [NameSet] -> Maybe OccName
1378 choose_one nss = case nameSetToList (unionManyNameSets nss) of
1380 (n:ns) -> Just (nameOccName n)
1382 --------------------------
1383 famInstToIfaceFamInst :: FamInst -> IfaceFamInst
1384 famInstToIfaceFamInst fi@(FamInst { fi_tycon = tycon,
1385 fi_fam = fam, fi_tcs = mb_tcs })
1386 = IfaceFamInst { ifFamInstTyCon = toIfaceTyCon tycon
1387 , ifFamInstFam = fam
1388 , ifFamInstTys = map do_rough mb_tcs }
1390 do_rough Nothing = Nothing
1391 do_rough (Just n) = Just (toIfaceTyCon_name n)
1393 --------------------------
1394 toIfaceLetBndr id = IfLetBndr (occNameFS (getOccName id))
1395 (toIfaceType (idType id))
1398 -- Stripped-down version of tcIfaceIdInfo
1399 -- Change this if you want to export more IdInfo for
1400 -- non-top-level Ids. Don't forget to change
1401 -- CoreTidy.tidyLetBndr too!
1403 -- See Note [IdInfo on nested let-bindings] in IfaceSyn
1405 inline_prag = inlinePragInfo id_info
1406 prag_info | isAlwaysActive inline_prag = NoInfo
1407 | otherwise = HasInfo [HsInline inline_prag]
1409 --------------------------
1410 toIfaceIdInfo :: IdInfo -> [IfaceInfoItem]
1411 toIfaceIdInfo id_info
1412 = catMaybes [arity_hsinfo, caf_hsinfo, strict_hsinfo,
1413 inline_hsinfo, wrkr_hsinfo, unfold_hsinfo]
1415 ------------ Arity --------------
1416 arity_info = arityInfo id_info
1417 arity_hsinfo | arity_info == 0 = Nothing
1418 | otherwise = Just (HsArity arity_info)
1420 ------------ Caf Info --------------
1421 caf_info = cafInfo id_info
1422 caf_hsinfo = case caf_info of
1423 NoCafRefs -> Just HsNoCafRefs
1426 ------------ Strictness --------------
1427 -- No point in explicitly exporting TopSig
1428 strict_hsinfo = case newStrictnessInfo id_info of
1429 Just sig | not (isTopSig sig) -> Just (HsStrictness sig)
1432 ------------ Worker --------------
1433 work_info = workerInfo id_info
1434 has_worker = workerExists work_info
1435 wrkr_hsinfo = case work_info of
1436 HasWorker work_id wrap_arity ->
1437 Just (HsWorker ((idName work_id)) wrap_arity)
1440 ------------ Unfolding --------------
1441 -- The unfolding is redundant if there is a worker
1442 unfold_info = unfoldingInfo id_info
1443 rhs = unfoldingTemplate unfold_info
1444 no_unfolding = neverUnfold unfold_info
1445 -- The CoreTidy phase retains unfolding info iff
1446 -- we want to expose the unfolding, taking into account
1447 -- unconditional NOINLINE, etc. See TidyPgm.addExternal
1448 unfold_hsinfo | no_unfolding = Nothing
1449 | has_worker = Nothing -- Unfolding is implicit
1450 | otherwise = Just (HsUnfold (toIfaceExpr rhs))
1452 ------------ Inline prag --------------
1453 inline_prag = inlinePragInfo id_info
1454 inline_hsinfo | isAlwaysActive inline_prag = Nothing
1455 | no_unfolding && not has_worker = Nothing
1456 -- If the iface file give no unfolding info, we
1457 -- don't need to say when inlining is OK!
1458 | otherwise = Just (HsInline inline_prag)
1460 --------------------------
1461 coreRuleToIfaceRule :: Module -> CoreRule -> IfaceRule
1462 coreRuleToIfaceRule mod (BuiltinRule { ru_fn = fn})
1463 = pprTrace "toHsRule: builtin" (ppr fn) $
1466 coreRuleToIfaceRule mod (Rule { ru_name = name, ru_fn = fn,
1467 ru_act = act, ru_bndrs = bndrs,
1468 ru_args = args, ru_rhs = rhs })
1469 = IfaceRule { ifRuleName = name, ifActivation = act,
1470 ifRuleBndrs = map toIfaceBndr bndrs,
1472 ifRuleArgs = map do_arg args,
1473 ifRuleRhs = toIfaceExpr rhs,
1476 -- For type args we must remove synonyms from the outermost
1477 -- level. Reason: so that when we read it back in we'll
1478 -- construct the same ru_rough field as we have right now;
1480 do_arg (Type ty) = IfaceType (toIfaceType (deNoteType ty))
1481 do_arg arg = toIfaceExpr arg
1483 -- Compute orphanhood. See Note [Orphans] in IfaceSyn
1484 -- A rule is an orphan only if none of the variables
1485 -- mentioned on its left-hand side are locally defined
1486 lhs_names = fn : nameSetToList (exprsFreeNames args)
1487 -- No need to delete bndrs, because
1488 -- exprsFreeNames finds only External names
1490 orph = case filter (nameIsLocalOrFrom mod) lhs_names of
1491 (n:ns) -> Just (nameOccName n)
1494 bogusIfaceRule :: Name -> IfaceRule
1495 bogusIfaceRule id_name
1496 = IfaceRule { ifRuleName = FSLIT("bogus"), ifActivation = NeverActive,
1497 ifRuleBndrs = [], ifRuleHead = id_name, ifRuleArgs = [],
1498 ifRuleRhs = IfaceExt id_name, ifRuleOrph = Nothing }
1500 ---------------------
1501 toIfaceExpr :: CoreExpr -> IfaceExpr
1502 toIfaceExpr (Var v) = toIfaceVar v
1503 toIfaceExpr (Lit l) = IfaceLit l
1504 toIfaceExpr (Type ty) = IfaceType (toIfaceType ty)
1505 toIfaceExpr (Lam x b) = IfaceLam (toIfaceBndr x) (toIfaceExpr b)
1506 toIfaceExpr (App f a) = toIfaceApp f [a]
1507 toIfaceExpr (Case s x ty as) = IfaceCase (toIfaceExpr s) (getFS x) (toIfaceType ty) (map toIfaceAlt as)
1508 toIfaceExpr (Let b e) = IfaceLet (toIfaceBind b) (toIfaceExpr e)
1509 toIfaceExpr (Cast e co) = IfaceCast (toIfaceExpr e) (toIfaceType co)
1510 toIfaceExpr (Note n e) = IfaceNote (toIfaceNote n) (toIfaceExpr e)
1512 ---------------------
1513 toIfaceNote (SCC cc) = IfaceSCC cc
1514 toIfaceNote InlineMe = IfaceInlineMe
1515 toIfaceNote (CoreNote s) = IfaceCoreNote s
1517 ---------------------
1518 toIfaceBind (NonRec b r) = IfaceNonRec (toIfaceLetBndr b) (toIfaceExpr r)
1519 toIfaceBind (Rec prs) = IfaceRec [(toIfaceLetBndr b, toIfaceExpr r) | (b,r) <- prs]
1521 ---------------------
1522 toIfaceAlt (c,bs,r) = (toIfaceCon c, map getFS bs, toIfaceExpr r)
1524 ---------------------
1525 toIfaceCon (DataAlt dc) | isTupleTyCon tc = IfaceTupleAlt (tupleTyConBoxity tc)
1526 | otherwise = IfaceDataAlt (getName dc)
1528 tc = dataConTyCon dc
1530 toIfaceCon (LitAlt l) = IfaceLitAlt l
1531 toIfaceCon DEFAULT = IfaceDefault
1533 ---------------------
1534 toIfaceApp (App f a) as = toIfaceApp f (a:as)
1535 toIfaceApp (Var v) as
1536 = case isDataConWorkId_maybe v of
1537 -- We convert the *worker* for tuples into IfaceTuples
1538 Just dc | isTupleTyCon tc && saturated
1539 -> IfaceTuple (tupleTyConBoxity tc) tup_args
1541 val_args = dropWhile isTypeArg as
1542 saturated = val_args `lengthIs` idArity v
1543 tup_args = map toIfaceExpr val_args
1544 tc = dataConTyCon dc
1546 other -> mkIfaceApps (toIfaceVar v) as
1548 toIfaceApp e as = mkIfaceApps (toIfaceExpr e) as
1550 mkIfaceApps f as = foldl (\f a -> IfaceApp f (toIfaceExpr a)) f as
1552 ---------------------
1553 toIfaceVar :: Id -> IfaceExpr
1555 | Just fcall <- isFCallId_maybe v = IfaceFCall fcall (toIfaceType (idType v))
1556 -- Foreign calls have special syntax
1557 | isExternalName name = IfaceExt name
1558 | Just (TickBox m ix) <- isTickBoxOp_maybe v
1560 | otherwise = IfaceLcl (getFS name)