2 % (c) The University of Glasgow, 2002
4 % The Compilation Manager
7 {-# OPTIONS -fvia-C #-}
11 CmState, emptyCmState, -- abstract
13 cmInit, -- :: GhciMode -> IO CmState
15 cmDepAnal, -- :: CmState -> DynFlags -> [FilePath] -> IO ModuleGraph
17 cmLoadModules, -- :: CmState -> DynFlags -> ModuleGraph
18 -- -> IO (CmState, [String])
20 cmUnload, -- :: CmState -> DynFlags -> IO CmState
23 cmModuleIsInterpreted, -- :: CmState -> String -> IO Bool
25 cmSetContext, -- :: CmState -> DynFlags -> [String] -> [String] -> IO CmState
26 cmGetContext, -- :: CmState -> IO ([String],[String])
28 cmInfoThing, -- :: CmState -> DynFlags -> String
29 -- -> IO (CmState, [(TyThing,Fixity)])
31 cmBrowseModule, -- :: CmState -> IO [TyThing]
34 cmRunStmt, -- :: CmState -> DynFlags -> String
35 -- -> IO (CmState, CmRunResult)
37 cmTypeOfExpr, -- :: CmState -> DynFlags -> String
38 -- -> IO (CmState, Maybe String)
40 cmTypeOfName, -- :: CmState -> Name -> IO (Maybe String)
43 cmCompileExpr, -- :: CmState -> DynFlags -> String
44 -- -> IO (CmState, Maybe HValue)
46 cmGetModuleGraph, -- :: CmState -> ModuleGraph
47 cmGetLinkables, -- :: CmState -> [Linkable]
49 cmGetBindings, -- :: CmState -> [TyThing]
50 cmGetPrintUnqual, -- :: CmState -> PrintUnqualified
58 #include "HsVersions.h"
66 import DriverState ( v_Output_file )
71 import HscMain ( initPersistentCompilerState, hscThing,
74 import HscMain ( initPersistentCompilerState )
77 import Name ( Name, NamedThing(..), nameRdrName, nameModule,
78 isHomePackageName, isGlobalName )
80 import Rename ( mkGlobalContext )
81 import RdrName ( emptyRdrEnv )
85 import Unique ( Uniquable )
86 import Digraph ( SCC(..), stronglyConnComp, flattenSCC, flattenSCCs )
87 import ErrUtils ( showPass )
88 import SysTools ( cleanTempFilesExcept )
92 import CmdLineOpts ( DynFlags(..), getDynFlags )
97 import RdrName ( lookupRdrEnv )
98 import Id ( idType, idName )
99 import Type ( tidyType )
100 import VarEnv ( emptyTidyEnv )
101 import BasicTypes ( Fixity, defaultFixity )
102 import Interpreter ( HValue )
103 import HscMain ( hscStmt )
104 import PrelGHC ( unsafeCoerce# )
108 import Exception ( Exception, try )
112 import Exception ( throwDyn )
115 import Directory ( getModificationTime, doesFileExist )
124 -- Persistent state for the entire system
127 hst :: HomeSymbolTable, -- home symbol table
128 hit :: HomeIfaceTable, -- home interface table
129 ui :: UnlinkedImage, -- the unlinked images
130 mg :: ModuleGraph, -- the module graph
131 gmode :: GhciMode, -- NEVER CHANGES
132 ic :: InteractiveContext, -- command-line binding info
134 pcs :: PersistentCompilerState, -- compile's persistent state
135 pls :: PersistentLinkerState -- link's persistent state
138 emptyCmState :: GhciMode -> IO CmState
140 = do pcs <- initPersistentCompilerState
142 return (CmState { hst = emptySymbolTable,
143 hit = emptyIfaceTable,
147 ic = emptyInteractiveContext,
151 emptyInteractiveContext
152 = InteractiveContext { ic_toplev_scope = [],
154 ic_rn_gbl_env = emptyRdrEnv,
155 ic_print_unqual = alwaysQualify,
156 ic_rn_local_env = emptyRdrEnv,
157 ic_type_env = emptyTypeEnv }
160 type UnlinkedImage = [Linkable] -- the unlinked images (should be a set, really)
161 emptyUI :: UnlinkedImage
164 type ModuleGraph = [ModSummary] -- the module graph, topologically sorted
165 emptyMG :: ModuleGraph
168 -----------------------------------------------------------------------------
169 -- Produce an initial CmState.
171 cmInit :: GhciMode -> IO CmState
172 cmInit mode = emptyCmState mode
174 -----------------------------------------------------------------------------
175 -- Grab information from the CmState
177 cmGetModuleGraph = mg
180 cmGetBindings cmstate = nameEnvElts (ic_type_env (ic cmstate))
181 cmGetPrintUnqual cmstate = ic_print_unqual (ic cmstate)
183 -----------------------------------------------------------------------------
184 -- Setting the context doesn't throw away any bindings; the bindings
185 -- we've built up in the InteractiveContext simply move to the new
186 -- module. They always shadow anything in scope in the current context.
189 :: CmState -> DynFlags
190 -> [String] -- take the top-level scopes of these modules
191 -> [String] -- and the just the exports from these
193 cmSetContext cmstate dflags toplevs exports = do
194 let CmState{ hit=hit, hst=hst, pcs=pcs, ic=old_ic } = cmstate
196 toplev_mods <- mapM (getTopLevModule hit) (map mkModuleName toplevs)
197 export_mods <- mapM (moduleNameToModule hit) (map mkModuleName exports)
199 (new_pcs, print_unqual, maybe_env)
200 <- mkGlobalContext dflags hit hst pcs toplev_mods export_mods
203 Nothing -> return cmstate
204 Just env -> return cmstate{ pcs = new_pcs,
205 ic = old_ic{ ic_toplev_scope = toplev_mods,
206 ic_exports = export_mods,
208 ic_print_unqual = print_unqual } }
210 getTopLevModule hit mn =
211 case lookupModuleEnvByName hit mn of
213 | Just _ <- mi_globals iface -> return (mi_module iface)
214 _other -> throwDyn (CmdLineError (
215 "cannot enter the top-level scope of a compiled module (module `" ++
216 moduleNameUserString mn ++ "')"))
218 moduleNameToModule :: HomeIfaceTable -> ModuleName -> IO Module
219 moduleNameToModule hit mn = do
220 case lookupModuleEnvByName hit mn of
221 Just iface -> return (mi_module iface)
222 _not_a_home_module -> do
223 maybe_stuff <- findModule mn
225 Nothing -> throwDyn (CmdLineError ("can't find module `"
226 ++ moduleNameUserString mn ++ "'"))
227 Just (m,_) -> return m
229 cmGetContext :: CmState -> IO ([String],[String])
230 cmGetContext CmState{ic=ic} =
231 return (map moduleUserString (ic_toplev_scope ic),
232 map moduleUserString (ic_exports ic))
234 cmModuleIsInterpreted :: CmState -> String -> IO Bool
235 cmModuleIsInterpreted cmstate str
236 = case lookupModuleEnvByName (hit cmstate) (mkModuleName str) of
237 Just iface -> return (not (isNothing (mi_globals iface)))
238 _not_a_home_module -> return False
240 -----------------------------------------------------------------------------
241 -- cmInfoThing: convert a String to a TyThing
243 -- A string may refer to more than one TyThing (eg. a constructor,
244 -- and type constructor), so we return a list of all the possible TyThings.
247 cmInfoThing :: CmState -> DynFlags -> String -> IO (CmState, [(TyThing,Fixity)])
248 cmInfoThing cmstate dflags id
249 = do (new_pcs, things) <- hscThing dflags hst hit pcs icontext id
250 let pairs = map (\x -> (x, getFixity new_pcs (getName x))) things
251 return (cmstate{ pcs=new_pcs }, pairs)
253 CmState{ hst=hst, hit=hit, pcs=pcs, pls=pls, ic=icontext } = cmstate
255 getFixity :: PersistentCompilerState -> Name -> Fixity
258 Just iface <- lookupModuleEnv iface_table (nameModule name),
259 Just fixity <- lookupNameEnv (mi_fixities iface) name
263 where iface_table | isHomePackageName name = hit
264 | otherwise = pcs_PIT pcs
267 -- ---------------------------------------------------------------------------
268 -- cmBrowseModule: get all the TyThings defined in a module
271 cmBrowseModule :: CmState -> DynFlags -> String -> Bool
272 -> IO (CmState, [TyThing])
273 cmBrowseModule cmstate dflags str exports_only = do
274 let mn = mkModuleName str
275 mod <- moduleNameToModule hit mn
276 (pcs1, maybe_ty_things)
277 <- hscModuleContents dflags hst hit pcs mod exports_only
278 case maybe_ty_things of
279 Nothing -> return (cmstate{pcs=pcs1}, [])
280 Just ty_things -> return (cmstate{pcs=pcs1}, ty_things)
282 CmState{ hst=hst, hit=hit, pcs=pcs, pls=pls, ic=icontext } = cmstate
285 -----------------------------------------------------------------------------
286 -- cmRunStmt: Run a statement/expr.
290 = CmRunOk [Name] -- names bound by this evaluation
292 | CmRunException Exception -- statement raised an exception
294 cmRunStmt :: CmState -> DynFlags -> String -> IO (CmState, CmRunResult)
295 cmRunStmt cmstate@CmState{ hst=hst, hit=hit, pcs=pcs, pls=pls, ic=icontext }
298 let InteractiveContext {
299 ic_rn_local_env = rn_env,
300 ic_type_env = type_env } = icontext
302 (new_pcs, maybe_stuff)
303 <- hscStmt dflags hst hit pcs icontext expr False{-stmt-}
306 Nothing -> return (cmstate{ pcs=new_pcs }, CmRunFailed)
307 Just (ids, _, bcos) -> do
309 -- update the interactive context
311 names = map idName ids
313 -- these names have just been shadowed
314 shadowed = [ n | r <- map nameRdrName names,
315 Just n <- [lookupRdrEnv rn_env r] ]
317 new_rn_env = extendLocalRdrEnv rn_env names
319 -- remove any shadowed bindings from the type_env
320 filtered_type_env = delListFromNameEnv type_env shadowed
322 new_type_env = extendNameEnvList filtered_type_env
323 [ (getName id, AnId id) | id <- ids]
325 new_ic = icontext { ic_rn_local_env = new_rn_env,
326 ic_type_env = new_type_env }
329 hval <- linkExpr pls bcos
332 let thing_to_run = unsafeCoerce# hval :: IO [HValue]
333 either_hvals <- sandboxIO thing_to_run
336 -> do hPutStrLn stderr ("unknown failure, code " ++ show err)
337 return ( cmstate{ pcs=new_pcs, ic=new_ic }, CmRunFailed )
342 return ( cmstate{ pcs=new_pcs, ic=new_ic },
345 -- Get the newly bound things, and bind them.
346 -- Don't forget to delete any shadowed bindings from the
347 -- closure_env, lest we end up with a space leak.
348 pls <- delListFromClosureEnv pls shadowed
349 new_pls <- addListToClosureEnv pls (zip names hvals)
351 return (cmstate{ pcs=new_pcs, pls=new_pls, ic=new_ic },
355 -- We run the statement in a "sandbox" to protect the rest of the
356 -- system from anything the expression might do. For now, this
357 -- consists of just wrapping it in an exception handler, but see below
358 -- for another version.
360 sandboxIO :: IO a -> IO (Either Int (Either Exception a))
362 r <- Exception.try thing
366 -- This version of sandboxIO runs the expression in a completely new
367 -- RTS main thread. It is disabled for now because ^C exceptions
368 -- won't be delivered to the new thread, instead they'll be delivered
369 -- to the (blocked) GHCi main thread.
371 sandboxIO :: IO a -> IO (Either Int (Either Exception a))
373 st_thing <- newStablePtr (Exception.try thing)
374 alloca $ \ p_st_result -> do
375 stat <- rts_evalStableIO st_thing p_st_result
376 freeStablePtr st_thing
378 then do st_result <- peek p_st_result
379 result <- deRefStablePtr st_result
380 freeStablePtr st_result
381 return (Right result)
383 return (Left (fromIntegral stat))
385 foreign import "rts_evalStableIO" {- safe -}
386 rts_evalStableIO :: StablePtr (IO a) -> Ptr (StablePtr a) -> IO CInt
387 -- more informative than the C type!
391 -----------------------------------------------------------------------------
392 -- cmTypeOfExpr: returns a string representing the type of an expression
395 cmTypeOfExpr :: CmState -> DynFlags -> String -> IO (CmState, Maybe String)
396 cmTypeOfExpr cmstate dflags expr
397 = do (new_pcs, maybe_stuff)
398 <- hscStmt dflags hst hit pcs ic expr True{-just an expr-}
400 let new_cmstate = cmstate{pcs = new_pcs}
403 Nothing -> return (new_cmstate, Nothing)
404 Just (_, ty, _) -> return (new_cmstate, Just str)
406 str = showSDocForUser unqual (ppr tidy_ty)
407 unqual = ic_print_unqual ic
408 tidy_ty = tidyType emptyTidyEnv ty
410 CmState{ hst=hst, hit=hit, pcs=pcs, ic=ic } = cmstate
413 -----------------------------------------------------------------------------
414 -- cmTypeOfName: returns a string representing the type of a name.
417 cmTypeOfName :: CmState -> Name -> IO (Maybe String)
418 cmTypeOfName CmState{ hit=hit, pcs=pcs, ic=ic } name
419 = case lookupNameEnv (ic_type_env ic) name of
420 Nothing -> return Nothing
421 Just (AnId id) -> return (Just str)
423 unqual = ic_print_unqual ic
424 ty = tidyType emptyTidyEnv (idType id)
425 str = showSDocForUser unqual (ppr ty)
427 _ -> panic "cmTypeOfName"
430 -----------------------------------------------------------------------------
431 -- cmCompileExpr: compile an expression and deliver an HValue
434 cmCompileExpr :: CmState -> DynFlags -> String -> IO (CmState, Maybe HValue)
435 cmCompileExpr cmstate dflags expr
437 let InteractiveContext {
438 ic_rn_local_env = rn_env,
439 ic_type_env = type_env } = icontext
441 (new_pcs, maybe_stuff)
442 <- hscStmt dflags hst hit pcs icontext
443 ("let __cmCompileExpr = "++expr) False{-stmt-}
446 Nothing -> return (cmstate{ pcs=new_pcs }, Nothing)
447 Just (ids, _, bcos) -> do
450 hval <- linkExpr pls bcos
453 let thing_to_run = unsafeCoerce# hval :: IO [HValue]
454 hvals <- thing_to_run
457 ([id],[hv]) -> return (cmstate{ pcs=new_pcs }, Just hv)
458 _ -> panic "cmCompileExpr"
461 CmState{ hst=hst, hit=hit, pcs=pcs, pls=pls, ic=icontext } = cmstate
464 -----------------------------------------------------------------------------
465 -- Unload the compilation manager's state: everything it knows about the
466 -- current collection of modules in the Home package.
468 cmUnload :: CmState -> DynFlags -> IO CmState
469 cmUnload state@CmState{ gmode=mode, pls=pls, pcs=pcs } dflags
470 = do -- Throw away the old home dir cache
473 -- Unload everything the linker knows about
474 new_pls <- CmLink.unload mode dflags [] pls
476 -- Start with a fresh CmState, but keep the PersistentCompilerState
477 new_state <- cmInit mode
478 return new_state{ pcs=pcs, pls=new_pls }
481 -----------------------------------------------------------------------------
482 -- Trace dependency graph
484 -- This is a seperate pass so that the caller can back off and keep
485 -- the current state if the downsweep fails.
487 cmDepAnal :: CmState -> DynFlags -> [FilePath] -> IO ModuleGraph
488 cmDepAnal cmstate dflags rootnames
489 = do showPass dflags "Chasing dependencies"
490 when (verbosity dflags >= 1 && gmode cmstate == Batch) $
491 hPutStrLn stderr (showSDoc (hcat [
492 text progName, text ": chasing modules from: ",
493 hcat (punctuate comma (map text rootnames))]))
494 downsweep rootnames (mg cmstate)
496 -----------------------------------------------------------------------------
497 -- The real business of the compilation manager: given a system state and
498 -- a module name, try and bring the module up to date, probably changing
499 -- the system state at the same time.
501 cmLoadModules :: CmState
504 -> IO (CmState, -- new state
505 Bool, -- was successful
506 [String]) -- list of modules loaded
508 cmLoadModules cmstate1 dflags mg2unsorted
509 = do -- version 1's are the original, before downsweep
510 let pls1 = pls cmstate1
511 let pcs1 = pcs cmstate1
512 let hst1 = hst cmstate1
513 let hit1 = hit cmstate1
514 -- similarly, ui1 is the (complete) set of linkables from
515 -- the previous pass, if any.
516 let ui1 = ui cmstate1
518 let ghci_mode = gmode cmstate1 -- this never changes
520 -- Do the downsweep to reestablish the module graph
521 let verb = verbosity dflags
523 -- Find out if we have a Main module
525 = any ((=="Main").moduleNameUserString.modSummaryName)
528 let mg2unsorted_names = map modSummaryName mg2unsorted
530 -- reachable_from follows source as well as normal imports
531 let reachable_from :: ModuleName -> [ModuleName]
532 reachable_from = downwards_closure_of_module mg2unsorted
534 -- should be cycle free; ignores 'import source's
535 let mg2 = topological_sort False mg2unsorted
536 -- ... whereas this takes them into account. Used for
537 -- backing out partially complete cycles following a failed
538 -- upsweep, and for removing from hst/hit all the modules
539 -- not in strict downwards closure, during calls to compile.
540 let mg2_with_srcimps = topological_sort True mg2unsorted
542 -- Sort out which linkables we wish to keep in the unlinked image.
543 -- See getValidLinkables below for details.
544 (valid_old_linkables, new_linkables)
545 <- getValidLinkables ui1 mg2unsorted_names mg2_with_srcimps
547 -- putStrLn (showSDoc (vcat [ppr valid_old_linkables, ppr new_linkables]))
549 -- uniq of ModuleName is the same as Module, fortunately...
550 let hit2 = delListFromUFM hit1 (map linkableModName new_linkables)
552 -- When (verb >= 2) $
553 -- putStrLn (showSDoc (text "Valid linkables:"
554 -- <+> ppr valid_linkables))
556 -- Figure out a stable set of modules which can be retained
557 -- the top level envs, to avoid upsweeping them. Goes to a
558 -- bit of trouble to avoid upsweeping module cycles.
560 -- Construct a set S of stable modules like this:
561 -- Travel upwards, over the sccified graph. For each scc
562 -- of modules ms, add ms to S only if:
563 -- 1. All home imports of ms are either in ms or S
564 -- 2. A valid old linkable exists for each module in ms
566 stable_mods <- preUpsweep valid_old_linkables
567 mg2unsorted_names [] mg2_with_srcimps
570 = concatMap (findInSummaries mg2unsorted) stable_mods
573 = filter (\m -> linkableModName m `elem` stable_mods)
577 putStrLn (showSDoc (text "Stable modules:"
578 <+> sep (map (text.moduleNameUserString) stable_mods)))
580 -- unload any modules which are going to be re-linked this
582 pls2 <- CmLink.unload ghci_mode dflags stable_linkables pls1
584 -- we can now glom together our linkable sets
585 let valid_linkables = valid_old_linkables ++ new_linkables
587 -- We could at this point detect cycles which aren't broken by
588 -- a source-import, and complain immediately, but it seems better
589 -- to let upsweep_mods do this, so at least some useful work gets
590 -- done before the upsweep is abandoned.
592 = filter (\scc -> any (`notElem` stable_mods)
593 (map modSummaryName (flattenSCC scc)))
596 --hPutStrLn stderr "after tsort:\n"
597 --hPutStrLn stderr (showSDoc (vcat (map ppr mg2)))
599 -- Because we don't take into account source imports when doing
600 -- the topological sort, there shouldn't be any cycles in mg2.
601 -- If there is, we complain and give up -- the user needs to
602 -- break the cycle using a boot file.
604 -- Now do the upsweep, calling compile for each module in
605 -- turn. Final result is version 3 of everything.
607 let threaded2 = CmThreaded pcs1 hst1 hit2
609 -- clean up between compilations
610 let cleanup = cleanTempFilesExcept verb
611 (ppFilesFromSummaries (flattenSCCs upsweep_these))
613 (upsweep_complete_success, threaded3, modsUpswept, newLis)
614 <- upsweep_mods ghci_mode dflags valid_linkables reachable_from
615 threaded2 cleanup upsweep_these
617 let ui3 = add_to_ui valid_linkables newLis
618 let (CmThreaded pcs3 hst3 hit3) = threaded3
620 -- At this point, modsUpswept and newLis should have the same
621 -- length, so there is one new (or old) linkable for each
622 -- mod which was processed (passed to compile).
624 -- Make modsDone be the summaries for each home module now
625 -- available; this should equal the domains of hst3 and hit3.
626 -- (NOT STRICTLY TRUE if an interactive session was started
627 -- with some object on disk ???)
628 -- Get in in a roughly top .. bottom order (hence reverse).
630 let modsDone = reverse modsUpswept ++ stable_summaries
632 -- Try and do linking in some form, depending on whether the
633 -- upsweep was completely or only partially successful.
635 if upsweep_complete_success
638 -- Easy; just relink it all.
639 do when (verb >= 2) $
640 hPutStrLn stderr "Upsweep completely successful."
642 -- clean up after ourselves
643 cleanTempFilesExcept verb (ppFilesFromSummaries modsDone)
645 -- issue a warning for the confusing case where the user said '-o foo'
646 -- but we're not going to do any linking.
647 ofile <- readIORef v_Output_file
648 when (ghci_mode == Batch && isJust ofile && not a_root_is_Main
650 hPutStrLn stderr "Warning: output was redirected with -o, but no output will be generated\nbecause there is no Main module."
652 -- link everything together
653 linkresult <- link ghci_mode dflags a_root_is_Main ui3 pls2
655 cmLoadFinish True linkresult
656 hst3 hit3 ui3 modsDone ghci_mode pcs3
659 -- Tricky. We need to back out the effects of compiling any
660 -- half-done cycles, both so as to clean up the top level envs
661 -- and to avoid telling the interactive linker to link them.
662 do when (verb >= 2) $
663 hPutStrLn stderr "Upsweep partially successful."
666 = map modSummaryName modsDone
667 let mods_to_zap_names
668 = findPartiallyCompletedCycles modsDone_names
671 = filter ((`notElem` mods_to_zap_names).modSummaryName)
674 let (hst4, hit4, ui4)
675 = retainInTopLevelEnvs (map modSummaryName mods_to_keep)
678 -- clean up after ourselves
679 cleanTempFilesExcept verb (ppFilesFromSummaries mods_to_keep)
681 -- link everything together
682 linkresult <- link ghci_mode dflags False ui4 pls2
684 cmLoadFinish False linkresult
685 hst4 hit4 ui4 mods_to_keep ghci_mode pcs3
688 -- Finish up after a cmLoad.
690 -- If the link failed, unload everything and return.
691 cmLoadFinish ok (LinkFailed pls) hst hit ui mods ghci_mode pcs = do
692 dflags <- getDynFlags
693 new_pls <- CmLink.unload ghci_mode dflags [] pls
694 new_state <- cmInit ghci_mode
695 return (new_state{ pcs=pcs, pls=new_pls }, False, [])
697 -- Empty the interactive context and set the module context to the topmost
698 -- newly loaded module, or the Prelude if none were loaded.
699 cmLoadFinish ok (LinkOK pls) hst hit ui mods ghci_mode pcs
700 = do let new_cmstate = CmState{ hst=hst, hit=hit, ui=ui, mg=mods,
701 gmode=ghci_mode, pcs=pcs, pls=pls,
702 ic = emptyInteractiveContext }
703 mods_loaded = map (moduleNameUserString.modSummaryName) mods
705 return (new_cmstate, ok, mods_loaded)
707 -- used to fish out the preprocess output files for the purposes
709 ppFilesFromSummaries summaries
710 = [ fn | Just fn <- map toPpFile summaries ]
713 | hspp /= ml_hs_file loc = hspp
714 | otherwise = Nothing
716 loc = ms_location sum
717 hspp = ml_hspp_file loc
720 -----------------------------------------------------------------------------
723 -- For each module (or SCC of modules), we take:
725 -- - an on-disk linkable, if this is the first time around and one
728 -- - the old linkable, otherwise (and if one is available).
730 -- and we throw away the linkable if it is older than the source
731 -- file. We ignore the on-disk linkables unless all of the dependents
732 -- of this SCC also have on-disk linkables.
734 -- If a module has a valid linkable, then it may be STABLE (see below),
735 -- and it is classified as SOURCE UNCHANGED for the purposes of calling
738 -- ToDo: this pass could be merged with the preUpsweep.
741 :: [Linkable] -- old linkables
742 -> [ModuleName] -- all home modules
743 -> [SCC ModSummary] -- all modules in the program, dependency order
744 -> IO ( [Linkable], -- still-valid linkables
745 [Linkable] -- new linkables we just found
748 getValidLinkables old_linkables all_home_mods module_graph = do
749 ls <- foldM (getValidLinkablesSCC old_linkables all_home_mods)
751 return (partition_it ls [] [])
753 partition_it [] valid new = (valid,new)
754 partition_it ((l,b):ls) valid new
755 | b = partition_it ls valid (l:new)
756 | otherwise = partition_it ls (l:valid) new
759 getValidLinkablesSCC old_linkables all_home_mods new_linkables scc0
761 scc = flattenSCC scc0
762 scc_names = map modSummaryName scc
763 home_module m = m `elem` all_home_mods && m `notElem` scc_names
764 scc_allhomeimps = nub (filter home_module (concatMap ms_imps scc))
765 -- NB. ms_imps, not ms_allimps above. We don't want to
766 -- force a module's SOURCE imports to be already compiled for
767 -- its object linkable to be valid.
770 case findModuleLinkable_maybe (map fst new_linkables) m of
772 Just l -> isObjectLinkable l
774 objects_allowed = all has_object scc_allhomeimps
778 <- foldM (getValidLinkable old_linkables objects_allowed) [] scc
780 -- since an scc can contain only all objects or no objects at all,
781 -- we have to check whether we got all objects or not, and re-do
782 -- the linkable check if not.
785 && not (all isObjectLinkable (map fst new_linkables'))
786 then foldM (getValidLinkable old_linkables False) [] scc
787 else return new_linkables'
789 return (new_linkables ++ new_linkables')
792 getValidLinkable :: [Linkable] -> Bool -> [(Linkable,Bool)] -> ModSummary
793 -> IO [(Linkable,Bool)]
794 -- True <=> linkable is new
795 getValidLinkable old_linkables objects_allowed new_linkables summary
796 = do let mod_name = modSummaryName summary
799 <- if (not objects_allowed)
802 else case ml_obj_file (ms_location summary) of
803 Just obj_fn -> maybe_getFileLinkable mod_name obj_fn
804 Nothing -> return Nothing
806 let old_linkable = findModuleLinkable_maybe old_linkables mod_name
809 case (old_linkable, maybe_disk_linkable) of
810 (Nothing, Nothing) -> []
812 -- new object linkable just appeared
813 (Nothing, Just l) -> up_to_date l True
816 | isObjectLinkable l -> []
817 -- object linkable disappeared! In case we need to
818 -- relink the module, disregard the old linkable and
819 -- just interpret the module from now on.
820 | otherwise -> up_to_date l False
821 -- old byte code linkable
824 | not (isObjectLinkable l) -> up_to_date l False
825 -- if the previous linkable was interpreted, then we
826 -- ignore a newly compiled version, because the version
827 -- numbers in the interface file will be out-of-sync with
828 -- our internal ones.
829 | linkableTime l' > linkableTime l -> up_to_date l' True
830 | linkableTime l' == linkableTime l -> up_to_date l False
832 -- on-disk linkable has been replaced by an older one!
833 -- again, disregard the previous one.
836 | linkableTime l < ms_hs_date summary = []
837 | otherwise = [(l,b)]
838 -- why '<' rather than '<=' above? If the filesystem stores
839 -- times to the nearset second, we may occasionally find that
840 -- the object & source have the same modification time,
841 -- especially if the source was automatically generated
842 -- and compiled. Using >= is slightly unsafe, but it matches
845 return (new_linkables' ++ new_linkables)
848 maybe_getFileLinkable :: ModuleName -> FilePath -> IO (Maybe Linkable)
849 maybe_getFileLinkable mod obj_fn
850 = do obj_exist <- doesFileExist obj_fn
854 do let stub_fn = case splitFilename3 obj_fn of
855 (dir, base, ext) -> dir ++ "/" ++ base ++ ".stub_o"
856 stub_exist <- doesFileExist stub_fn
857 obj_time <- getModificationTime obj_fn
859 then return (Just (LM obj_time mod [DotO obj_fn, DotO stub_fn]))
860 else return (Just (LM obj_time mod [DotO obj_fn]))
863 -----------------------------------------------------------------------------
864 -- Do a pre-upsweep without use of "compile", to establish a
865 -- (downward-closed) set of stable modules for which we won't call compile.
868 -- * has a valid linkable (see getValidLinkables above)
869 -- * depends only on stable modules
870 -- * has an interface in the HIT (interactive mode only)
872 preUpsweep :: [Linkable] -- new valid linkables
873 -> [ModuleName] -- names of all mods encountered in downsweep
874 -> [ModuleName] -- accumulating stable modules
875 -> [SCC ModSummary] -- scc-ified mod graph, including src imps
876 -> IO [ModuleName] -- stable modules
878 preUpsweep valid_lis all_home_mods stable [] = return stable
879 preUpsweep valid_lis all_home_mods stable (scc0:sccs)
880 = do let scc = flattenSCC scc0
881 scc_allhomeimps :: [ModuleName]
883 = nub (filter (`elem` all_home_mods) (concatMap ms_allimps scc))
884 all_imports_in_scc_or_stable
885 = all in_stable_or_scc scc_allhomeimps
887 = map modSummaryName scc
889 = m `elem` scc_names || m `elem` stable
891 -- now we check for valid linkables: each module in the SCC must
892 -- have a valid linkable (see getValidLinkables above).
893 has_valid_linkable new_summary
894 = isJust (findModuleLinkable_maybe valid_lis modname)
895 where modname = modSummaryName new_summary
897 scc_is_stable = all_imports_in_scc_or_stable
898 && all has_valid_linkable scc
901 then preUpsweep valid_lis all_home_mods (scc_names++stable) sccs
902 else preUpsweep valid_lis all_home_mods stable sccs
905 -- Helper for preUpsweep. Assuming that new_summary's imports are all
906 -- stable (in the sense of preUpsweep), determine if new_summary is itself
907 -- stable, and, if so, in batch mode, return its linkable.
908 findInSummaries :: [ModSummary] -> ModuleName -> [ModSummary]
909 findInSummaries old_summaries mod_name
910 = [s | s <- old_summaries, modSummaryName s == mod_name]
912 findModInSummaries :: [ModSummary] -> Module -> Maybe ModSummary
913 findModInSummaries old_summaries mod
914 = case [s | s <- old_summaries, ms_mod s == mod] of
918 -- Return (names of) all those in modsDone who are part of a cycle
919 -- as defined by theGraph.
920 findPartiallyCompletedCycles :: [ModuleName] -> [SCC ModSummary] -> [ModuleName]
921 findPartiallyCompletedCycles modsDone theGraph
925 chew ((AcyclicSCC v):rest) = chew rest -- acyclic? not interesting.
926 chew ((CyclicSCC vs):rest)
927 = let names_in_this_cycle = nub (map modSummaryName vs)
929 = nub ([done | done <- modsDone,
930 done `elem` names_in_this_cycle])
931 chewed_rest = chew rest
933 if not (null mods_in_this_cycle)
934 && length mods_in_this_cycle < length names_in_this_cycle
935 then mods_in_this_cycle ++ chewed_rest
939 -- Add the given (LM-form) Linkables to the UI, overwriting previous
940 -- versions if they exist.
941 add_to_ui :: UnlinkedImage -> [Linkable] -> UnlinkedImage
943 = filter (not_in lis) ui ++ lis
945 not_in :: [Linkable] -> Linkable -> Bool
947 = all (\l -> linkableModName l /= mod) lis
948 where mod = linkableModName li
951 data CmThreaded -- stuff threaded through individual module compilations
952 = CmThreaded PersistentCompilerState HomeSymbolTable HomeIfaceTable
955 -- Compile multiple modules, stopping as soon as an error appears.
956 -- There better had not be any cyclic groups here -- we check for them.
957 upsweep_mods :: GhciMode
959 -> UnlinkedImage -- valid linkables
960 -> (ModuleName -> [ModuleName]) -- to construct downward closures
961 -> CmThreaded -- PCS & HST & HIT
962 -> IO () -- how to clean up unwanted tmp files
963 -> [SCC ModSummary] -- mods to do (the worklist)
964 -- ...... RETURNING ......
965 -> IO (Bool{-complete success?-},
967 [ModSummary], -- mods which succeeded
968 [Linkable]) -- new linkables
970 upsweep_mods ghci_mode dflags oldUI reachable_from threaded cleanup
972 = return (True, threaded, [], [])
974 upsweep_mods ghci_mode dflags oldUI reachable_from threaded cleanup
976 = do hPutStrLn stderr ("Module imports form a cycle for modules:\n\t" ++
977 unwords (map (moduleNameUserString.modSummaryName) ms))
978 return (False, threaded, [], [])
980 upsweep_mods ghci_mode dflags oldUI reachable_from threaded cleanup
981 ((AcyclicSCC mod):mods)
982 = do --case threaded of
983 -- CmThreaded pcsz hstz hitz
984 -- -> putStrLn ("UPSWEEP_MOD: hit = " ++ show (map (moduleNameUserString.moduleName.mi_module) (eltsUFM hitz)))
986 (threaded1, maybe_linkable)
987 <- upsweep_mod ghci_mode dflags oldUI threaded mod
988 (reachable_from (modSummaryName mod))
990 -- remove unwanted tmp files between compilations
993 case maybe_linkable of
995 -> -- No errors; do the rest
996 do (restOK, threaded2, modOKs, linkables)
997 <- upsweep_mods ghci_mode dflags oldUI reachable_from
998 threaded1 cleanup mods
999 return (restOK, threaded2, mod:modOKs, linkable:linkables)
1000 Nothing -- we got a compilation error; give up now
1001 -> return (False, threaded1, [], [])
1004 -- Compile a single module. Always produce a Linkable for it if
1005 -- successful. If no compilation happened, return the old Linkable.
1006 upsweep_mod :: GhciMode
1012 -> IO (CmThreaded, Maybe Linkable)
1014 upsweep_mod ghci_mode dflags oldUI threaded1 summary1 reachable_inc_me
1016 let mod_name = modSummaryName summary1
1018 let (CmThreaded pcs1 hst1 hit1) = threaded1
1019 let old_iface = lookupUFM hit1 mod_name
1021 let maybe_old_linkable = findModuleLinkable_maybe oldUI mod_name
1023 source_unchanged = isJust maybe_old_linkable
1025 reachable_only = filter (/= (modSummaryName summary1))
1028 -- in interactive mode, all home modules below us *must* have an
1029 -- interface in the HIT. We never demand-load home interfaces in
1030 -- interactive mode.
1031 (hst1_strictDC, hit1_strictDC, [])
1032 = ASSERT(ghci_mode == Batch ||
1033 all (`elemUFM` hit1) reachable_only)
1034 retainInTopLevelEnvs reachable_only (hst1,hit1,[])
1037 = unJust "upsweep_mod:old_linkable" maybe_old_linkable
1040 | Just l <- maybe_old_linkable, isObjectLinkable l = True
1043 compresult <- compile ghci_mode summary1 source_unchanged
1044 have_object old_iface hst1_strictDC hit1_strictDC pcs1
1048 -- Compilation "succeeded", and may or may not have returned a new
1049 -- linkable (depending on whether compilation was actually performed
1051 CompOK pcs2 new_details new_iface maybe_new_linkable
1052 -> do let hst2 = addToUFM hst1 mod_name new_details
1053 hit2 = addToUFM hit1 mod_name new_iface
1054 threaded2 = CmThreaded pcs2 hst2 hit2
1056 return (threaded2, if isJust maybe_new_linkable
1057 then maybe_new_linkable
1058 else Just old_linkable)
1060 -- Compilation failed. compile may still have updated
1063 -> do let threaded2 = CmThreaded pcs2 hst1 hit1
1064 return (threaded2, Nothing)
1066 -- Filter modules in the top level envs (HST, HIT, UI).
1067 retainInTopLevelEnvs :: [ModuleName]
1068 -> (HomeSymbolTable, HomeIfaceTable, UnlinkedImage)
1069 -> (HomeSymbolTable, HomeIfaceTable, UnlinkedImage)
1070 retainInTopLevelEnvs keep_these (hst, hit, ui)
1071 = (retainInUFM hst keep_these,
1072 retainInUFM hit keep_these,
1073 filterModuleLinkables (`elem` keep_these) ui
1076 retainInUFM :: Uniquable key => UniqFM elt -> [key] -> UniqFM elt
1077 retainInUFM ufm keys_to_keep
1078 = listToUFM (concatMap (maybeLookupUFM ufm) keys_to_keep)
1079 maybeLookupUFM ufm u
1080 = case lookupUFM ufm u of Nothing -> []; Just val -> [(u, val)]
1082 -- Needed to clean up HIT and HST so that we don't get duplicates in inst env
1083 downwards_closure_of_module :: [ModSummary] -> ModuleName -> [ModuleName]
1084 downwards_closure_of_module summaries root
1085 = let toEdge :: ModSummary -> (ModuleName,[ModuleName])
1086 toEdge summ = (modSummaryName summ,
1087 filter (`elem` all_mods) (ms_allimps summ))
1089 all_mods = map modSummaryName summaries
1091 res = simple_transitive_closure (map toEdge summaries) [root]
1093 -- trace (showSDoc (text "DC of mod" <+> ppr root
1094 -- <+> text "=" <+> ppr res)) $
1097 -- Calculate transitive closures from a set of roots given an adjacency list
1098 simple_transitive_closure :: Eq a => [(a,[a])] -> [a] -> [a]
1099 simple_transitive_closure graph set
1100 = let set2 = nub (concatMap dsts set ++ set)
1101 dsts node = fromMaybe [] (lookup node graph)
1103 if length set == length set2
1105 else simple_transitive_closure graph set2
1108 -- Calculate SCCs of the module graph, with or without taking into
1109 -- account source imports.
1110 topological_sort :: Bool -> [ModSummary] -> [SCC ModSummary]
1111 topological_sort include_source_imports summaries
1113 toEdge :: ModSummary -> (ModSummary,ModuleName,[ModuleName])
1115 = (summ, modSummaryName summ,
1116 (if include_source_imports
1117 then ms_srcimps summ else []) ++ ms_imps summ)
1119 mash_edge :: (ModSummary,ModuleName,[ModuleName]) -> (ModSummary,Int,[Int])
1120 mash_edge (summ, m, m_imports)
1121 = case lookup m key_map of
1122 Nothing -> panic "reverse_topological_sort"
1123 Just mk -> (summ, mk,
1124 -- ignore imports not from the home package
1125 catMaybes (map (flip lookup key_map) m_imports))
1127 edges = map toEdge summaries
1128 key_map = zip [nm | (s,nm,imps) <- edges] [1 ..] :: [(ModuleName,Int)]
1129 scc_input = map mash_edge edges
1130 sccs = stronglyConnComp scc_input
1135 -----------------------------------------------------------------------------
1136 -- Downsweep (dependency analysis)
1138 -- Chase downwards from the specified root set, returning summaries
1139 -- for all home modules encountered. Only follow source-import
1142 -- We pass in the previous collection of summaries, which is used as a
1143 -- cache to avoid recalculating a module summary if the source is
1146 downsweep :: [FilePath] -> [ModSummary] -> IO [ModSummary]
1147 downsweep roots old_summaries
1148 = do rootSummaries <- mapM getRootSummary roots
1150 <- loop (concat (map ms_imps rootSummaries))
1151 (mkModuleEnv [ (mod, s) | s <- rootSummaries,
1152 let mod = ms_mod s, isHomeModule mod
1154 return all_summaries
1156 getRootSummary :: FilePath -> IO ModSummary
1158 | haskellish_src_file file
1159 = do exists <- doesFileExist file
1160 if exists then summariseFile file else do
1161 throwDyn (CmdLineError ("can't find file `" ++ file ++ "'"))
1163 = do exists <- doesFileExist hs_file
1164 if exists then summariseFile hs_file else do
1165 exists <- doesFileExist lhs_file
1166 if exists then summariseFile lhs_file else do
1167 let mod_name = mkModuleName file
1168 maybe_summary <- getSummary mod_name
1169 case maybe_summary of
1170 Nothing -> packageModErr mod_name
1173 hs_file = file ++ ".hs"
1174 lhs_file = file ++ ".lhs"
1176 getSummary :: ModuleName -> IO (Maybe ModSummary)
1178 = do found <- findModule nm
1180 Just (mod, location) -> do
1181 let old_summary = findModInSummaries old_summaries mod
1182 summarise mod location old_summary
1184 Nothing -> throwDyn (CmdLineError
1185 ("can't find module `"
1186 ++ showSDoc (ppr nm) ++ "'"))
1188 -- loop invariant: env doesn't contain package modules
1189 loop :: [ModuleName] -> ModuleEnv ModSummary -> IO [ModSummary]
1190 loop [] env = return (moduleEnvElts env)
1192 = do -- imports for modules we don't already have
1193 let needed_imps = nub (filter (not . (`elemUFM` env)) imps)
1196 needed_summaries <- mapM getSummary needed_imps
1198 -- get just the "home" modules
1199 let new_home_summaries = [ s | Just s <- needed_summaries ]
1201 -- loop, checking the new imports
1202 let new_imps = concat (map ms_imps new_home_summaries)
1203 loop new_imps (extendModuleEnvList env
1204 [ (ms_mod s, s) | s <- new_home_summaries ])
1206 -----------------------------------------------------------------------------
1207 -- Summarising modules
1209 -- We have two types of summarisation:
1211 -- * Summarise a file. This is used for the root module(s) passed to
1212 -- cmLoadModules. The file is read, and used to determine the root
1213 -- module name. The module name may differ from the filename.
1215 -- * Summarise a module. We are given a module name, and must provide
1216 -- a summary. The finder is used to locate the file in which the module
1219 summariseFile :: FilePath -> IO ModSummary
1221 = do hspp_fn <- preprocess file
1222 (srcimps,imps,mod_name) <- getImportsFromFile hspp_fn
1224 let (path, basename, _ext) = splitFilename3 file
1227 <- mkHomeModuleLocn mod_name (path ++ '/':basename) file
1230 <- case ml_hs_file location of
1231 Nothing -> noHsFileErr mod_name
1232 Just src_fn -> getModificationTime src_fn
1234 return (ModSummary mod
1235 location{ml_hspp_file=Just hspp_fn}
1236 srcimps imps src_timestamp)
1238 -- Summarise a module, and pick up source and timestamp.
1239 summarise :: Module -> ModuleLocation -> Maybe ModSummary
1240 -> IO (Maybe ModSummary)
1241 summarise mod location old_summary
1242 | not (isHomeModule mod) = return Nothing
1244 = do let hs_fn = unJust "summarise" (ml_hs_file location)
1246 case ml_hs_file location of {
1247 Nothing -> noHsFileErr mod;
1250 src_timestamp <- getModificationTime src_fn
1252 -- return the cached summary if the source didn't change
1253 case old_summary of {
1254 Just s | ms_hs_date s == src_timestamp -> return (Just s);
1257 hspp_fn <- preprocess hs_fn
1258 (srcimps,imps,mod_name) <- getImportsFromFile hspp_fn
1260 when (mod_name /= moduleName mod) $
1261 throwDyn (ProgramError
1262 (showSDoc (text hs_fn
1263 <> text ": file name does not match module name"
1264 <+> quotes (ppr (moduleName mod)))))
1266 return (Just (ModSummary mod location{ml_hspp_file=Just hspp_fn}
1267 srcimps imps src_timestamp))
1273 = throwDyn (CmdLineError (showSDoc (text "no source file for module" <+> quotes (ppr mod))))
1276 = throwDyn (CmdLineError (showSDoc (text "module" <+>
1277 quotes (ppr mod) <+>
1278 text "is a package module")))