2 % (c) The GRASP/AQUA Project, Glasgow University, 1993-2000
5 \section[GHC_Main]{Main driver for Glasgow Haskell compiler}
8 module HscMain ( HscResult(..), hscMain,
10 hscStmt, hscThing, hscModuleContents,
12 initPersistentCompilerState ) where
14 #include "HsVersions.h"
18 import ByteCodeGen ( byteCodeGen )
19 import CoreTidy ( tidyCoreExpr )
20 import CorePrep ( corePrepExpr )
21 import Rename ( renameStmt, renameRdrName, slurpIface )
22 import RdrName ( rdrNameOcc, setRdrNameOcc )
23 import RdrHsSyn ( RdrNameStmt )
24 import OccName ( dataName, tcClsName,
25 occNameSpace, setOccNameSpace )
27 import Id ( Id, idName, setGlobalIdDetails )
28 import IdInfo ( GlobalIdDetails(VanillaGlobal) )
29 import Name ( isLocalName )
30 import NameEnv ( lookupNameEnv )
31 import Module ( lookupModuleEnv )
32 import RdrName ( rdrEnvElts )
33 import PrelNames ( iNTERACTIVE )
34 import StringBuffer ( stringToStringBuffer )
35 import FastString ( mkFastString )
36 import Maybes ( catMaybes )
43 import RdrName ( mkRdrOrig )
45 import IdInfo ( CafInfo(..), CgInfoEnv, CgInfo(..) )
46 import StringBuffer ( hGetStringBuffer, freeStringBuffer )
48 import Lex ( ParseResult(..), ExtFlags(..), mkPState )
49 import SrcLoc ( mkSrcLoc )
50 import Finder ( findModule )
51 import Rename ( checkOldIface, renameModule, closeIfaceDecls )
52 import Rules ( emptyRuleBase )
53 import PrelInfo ( wiredInThingEnv, wiredInThings )
54 import PrelRules ( builtinRules )
55 import PrelNames ( knownKeyNames )
56 import MkIface ( mkFinalIface )
58 import InstEnv ( emptyInstEnv )
60 import Flattening ( flatten, flattenExpr )
62 import CoreUtils ( coreBindsSize )
63 import CoreTidy ( tidyCorePgm )
64 import CorePrep ( corePrepPgm )
66 import CoreToStg ( coreToStg )
67 import SimplStg ( stg2stg )
68 import CodeGen ( codeGen )
69 import CodeOutput ( codeOutput, outputForeignStubs )
71 import Module ( ModuleName, moduleName, mkHomeModule )
73 import DriverState ( v_HCHeader )
74 import ErrUtils ( dumpIfSet_dyn, showPass, printError )
75 import Util ( unJust )
76 import UniqSupply ( mkSplitUniqSupply )
78 import Bag ( consBag, emptyBag )
80 import HscStats ( ppSourceStats )
82 import FiniteMap ( FiniteMap, plusFM, emptyFM, addToFM )
83 import OccName ( OccName )
84 import Name ( Name, nameModule, nameOccName, getName )
85 import NameEnv ( emptyNameEnv, mkNameEnv )
86 import Module ( Module )
88 import IOExts ( newIORef, readIORef, writeIORef,
92 import Maybe ( isJust, fromJust )
95 import MkExternalCore ( emitExternalCore )
99 %************************************************************************
101 \subsection{The main compiler pipeline}
103 %************************************************************************
107 -- compilation failed
108 = HscFail PersistentCompilerState -- updated PCS
109 -- concluded that it wasn't necessary
110 | HscNoRecomp PersistentCompilerState -- updated PCS
111 ModDetails -- new details (HomeSymbolTable additions)
112 ModIface -- new iface (if any compilation was done)
114 | HscRecomp PersistentCompilerState -- updated PCS
115 ModDetails -- new details (HomeSymbolTable additions)
116 ModIface -- new iface (if any compilation was done)
117 Bool -- stub_h exists
118 Bool -- stub_c exists
120 (Maybe ([UnlinkedBCO],ItblEnv)) -- interpreted code, if any
122 (Maybe ()) -- no interpreted code whatsoever
125 -- no errors or warnings; the individual passes
126 -- (parse/rename/typecheck) print messages themselves
132 -> ModuleLocation -- location info
133 -> Bool -- True <=> source unchanged
134 -> Bool -- True <=> have an object file (for msgs only)
135 -> Maybe ModIface -- old interface, if available
136 -> HomeSymbolTable -- for home module ModDetails
138 -> PersistentCompilerState -- IN: persistent compiler state
141 hscMain ghci_mode dflags mod location source_unchanged have_object
142 maybe_old_iface hst hit pcs
143 = {-# SCC "hscMain" #-}
145 showPass dflags ("Checking old interface for hs = "
146 ++ show (ml_hs_file location)
147 ++ ", hspp = " ++ show (ml_hspp_file location));
149 (pcs_ch, errs_found, (recomp_reqd, maybe_checked_iface))
150 <- _scc_ "checkOldIface"
151 checkOldIface ghci_mode dflags hit hst pcs mod (ml_hi_file location)
152 source_unchanged maybe_old_iface;
155 return (HscFail pcs_ch)
158 let no_old_iface = not (isJust maybe_checked_iface)
159 what_next | recomp_reqd || no_old_iface = hscRecomp
160 | otherwise = hscNoRecomp
162 what_next ghci_mode dflags have_object mod location
163 maybe_checked_iface hst hit pcs_ch
167 -- we definitely expect to have the old interface available
168 hscNoRecomp ghci_mode dflags have_object
169 mod location (Just old_iface) hst hit pcs_ch
170 | ghci_mode == OneShot
172 when (verbosity dflags > 0) $
173 hPutStrLn stderr "compilation IS NOT required";
174 let { bomb = panic "hscNoRecomp:OneShot" };
175 return (HscNoRecomp pcs_ch bomb bomb)
179 when (verbosity dflags >= 1) $
180 hPutStrLn stderr ("Skipping " ++
181 showModMsg have_object mod location);
184 (pcs_cl, closure_errs, cl_hs_decls)
185 <- closeIfaceDecls dflags hit hst pcs_ch old_iface ;
187 return (HscFail pcs_cl)
192 <- typecheckIface dflags pcs_cl hst old_iface cl_hs_decls;
194 case maybe_tc_result of {
195 Nothing -> return (HscFail pcs_cl);
196 Just (pcs_tc, new_details) ->
198 return (HscNoRecomp pcs_tc new_details old_iface)
201 hscRecomp ghci_mode dflags have_object
202 mod location maybe_checked_iface hst hit pcs_ch
204 -- what target are we shooting for?
205 ; let toInterp = dopt_HscLang dflags == HscInterpreted
206 ; let toNothing = dopt_HscLang dflags == HscNothing
208 ; when (ghci_mode /= OneShot && verbosity dflags >= 1) $
209 hPutStrLn stderr ("Compiling " ++
210 showModMsg (not toInterp) mod location);
215 ; maybe_parsed <- myParseModule dflags
216 (unJust "hscRecomp:hspp" (ml_hspp_file location))
217 ; case maybe_parsed of {
218 Nothing -> return (HscFail pcs_ch);
219 Just rdr_module -> do {
220 ; let this_mod = mkHomeModule (hsModuleName rdr_module)
225 ; (pcs_rn, print_unqual, maybe_rn_result)
227 renameModule dflags ghci_mode hit hst pcs_ch this_mod rdr_module
228 ; case maybe_rn_result of {
229 Nothing -> return (HscFail pcs_ch);
230 Just (dont_discard, new_iface, rn_result) -> do {
237 typecheckModule dflags pcs_rn hst print_unqual rn_result
238 ; case maybe_tc_result of {
239 Nothing -> return (HscFail pcs_ch);
240 Just (pcs_tc, tc_result) -> do {
245 ; (ds_details, foreign_stuff)
247 deSugar dflags pcs_tc hst this_mod print_unqual tc_result
253 <- _scc_ "Flattening"
254 flatten dflags pcs_tc hst ds_details
257 <- _scc_ "pcs_middle"
258 if ghci_mode == OneShot
259 then do init_pcs <- initPersistentCompilerState
260 init_prs <- initPersistentRenamerState
262 rules = pcs_rules pcs_tc
263 orig_tc = prsOrig (pcs_PRS pcs_tc)
264 new_prs = init_prs{ prsOrig=orig_tc }
266 orig_tc `seq` rules `seq` new_prs `seq`
267 return init_pcs{ pcs_PRS = new_prs,
271 -- alive at this point:
282 core2core dflags pcs_middle hst dont_discard flat_details
287 ; cg_info_ref <- newIORef Nothing ;
288 ; let cg_info :: CgInfoEnv
289 cg_info = unsafePerformIO $ do {
290 maybe_cg_env <- readIORef cg_info_ref ;
292 Just env -> return env
293 Nothing -> do { printError "Urk! Looked at CgInfo too early!";
294 return emptyNameEnv } }
295 -- cg_info_ref will be filled in just after restOfCodeGeneration
296 -- Meanwhile, tidyCorePgm is careful not to look at cg_info!
298 ; (pcs_simpl, tidy_details)
300 tidyCorePgm dflags this_mod pcs_middle cg_info simpl_details
302 ; pcs_final <- if ghci_mode == OneShot then initPersistentCompilerState
303 else return pcs_simpl
305 -- alive at this point:
309 ; emitExternalCore dflags new_iface tidy_details
311 ; let final_details = tidy_details {md_binds = []}
312 ; final_details `seq` return ()
315 -- PREPARE FOR CODE GENERATION
317 -- Do saturation and convert to A-normal form
318 ; prepd_details <- _scc_ "CorePrep"
319 corePrepPgm dflags tidy_details
322 -- CONVERT TO STG and COMPLETE CODE GENERATION
325 ModDetails{md_binds=binds, md_types=env_tc} = prepd_details
327 local_tycons = typeEnvTyCons env_tc
328 local_classes = typeEnvClasses env_tc
330 imported_module_names = map ideclName (hsModuleImports rdr_module)
332 mod_name_to_Module nm
333 = do m <- findModule nm ; return (fst (fromJust m))
335 (h_code, c_code, headers, fe_binders) = foreign_stuff
337 -- turn the list of headers requested in foreign import
338 -- declarations into a string suitable for emission into generated
343 . map (\fname -> "#include \"" ++ _UNPK_ fname ++ "\"")
347 -- ...and add the string to the headers requested via command line
350 ; fhdrs <- readIORef v_HCHeader
351 ; writeIORef v_HCHeader (fhdrs ++ foreign_headers)
353 ; imported_modules <- mapM mod_name_to_Module imported_module_names
355 ; (stub_h_exists, stub_c_exists, maybe_bcos, final_iface )
359 ----------------- Generate byte code ------------------
360 (bcos,itbl_env) <- byteCodeGen dflags binds
361 local_tycons local_classes
363 -- Fill in the code-gen info
364 writeIORef cg_info_ref (Just emptyNameEnv)
366 ------------------ BUILD THE NEW ModIface ------------
367 final_iface <- _scc_ "MkFinalIface"
368 mkFinalIface ghci_mode dflags location
369 maybe_checked_iface new_iface tidy_details
371 ------------------ Create f-x-dynamic C-side stuff ---
372 (istub_h_exists, istub_c_exists)
373 <- outputForeignStubs dflags c_code h_code
375 return ( istub_h_exists, istub_c_exists,
376 Just (bcos,itbl_env), final_iface )
378 then error "GHC not compiled with interpreter"
382 ----------------- Convert to STG ------------------
383 (stg_binds, cost_centre_info, stg_back_end_info)
385 myCoreToStg dflags this_mod binds
387 -- Fill in the code-gen info for the earlier tidyCorePgm
388 writeIORef cg_info_ref (Just stg_back_end_info)
390 ------------------ BUILD THE NEW ModIface ------------
391 final_iface <- _scc_ "MkFinalIface"
392 mkFinalIface ghci_mode dflags location
393 maybe_checked_iface new_iface tidy_details
396 return (False, False, Nothing, final_iface)
398 ------------------ Code generation ------------------
399 abstractC <- _scc_ "CodeGen"
400 codeGen dflags this_mod imported_modules
401 cost_centre_info fe_binders
402 local_tycons stg_binds
404 ------------------ Code output -----------------------
405 (stub_h_exists, stub_c_exists)
406 <- codeOutput dflags this_mod [] --local_tycons
408 c_code h_code abstractC
410 return (stub_h_exists, stub_c_exists, Nothing, final_iface)
412 -- and the answer is ...
413 ; return (HscRecomp pcs_final
416 stub_h_exists stub_c_exists
420 myParseModule dflags src_filename
421 = do -------------------------- Parser ----------------
422 showPass dflags "Parser"
425 buf <- hGetStringBuffer True{-expand tabs-} src_filename
427 let exts = ExtFlags {glasgowExtsEF = dopt Opt_GlasgowExts dflags,
428 parrEF = dopt Opt_PArr dflags}
429 loc = mkSrcLoc (_PK_ src_filename) 1
431 case parseModule buf (mkPState loc exts) of {
433 PFailed err -> do { hPutStrLn stderr (showSDoc err);
434 freeStringBuffer buf;
437 POk _ rdr_module@(HsModule mod_name _ _ _ _ _ _) -> do {
439 dumpIfSet_dyn dflags Opt_D_dump_parsed "Parser" (ppr rdr_module) ;
441 dumpIfSet_dyn dflags Opt_D_source_stats "Source Statistics"
442 (ppSourceStats False rdr_module) ;
444 return (Just rdr_module)
445 -- ToDo: free the string buffer later.
449 myCoreToStg dflags this_mod tidy_binds
451 () <- coreBindsSize tidy_binds `seq` return ()
452 -- TEMP: the above call zaps some space usage allocated by the
453 -- simplifier, which for reasons I don't understand, persists
454 -- thoroughout code generation -- JRS
456 -- This is still necessary. -- SDM (10 Dec 2001)
458 stg_binds <- _scc_ "Core2Stg"
459 coreToStg dflags tidy_binds
461 (stg_binds2, cost_centre_info) <- _scc_ "Core2Stg"
462 stg2stg dflags this_mod stg_binds
464 let env_rhs :: CgInfoEnv
465 env_rhs = mkNameEnv [ caf_info `seq` (idName bndr, CgInfo caf_info)
466 | (bind,_) <- stg_binds2,
468 | stgBindHasCafRefs bind = MayHaveCafRefs
469 | otherwise = NoCafRefs,
470 bndr <- stgBinders bind ]
472 return (stg_binds2, cost_centre_info, env_rhs)
476 %************************************************************************
478 \subsection{Compiling a do-statement}
480 %************************************************************************
488 -> PersistentCompilerState -- IN: persistent compiler state
489 -> InteractiveContext -- Context for compiling
490 -> String -- The statement
491 -> Bool -- just treat it as an expression
492 -> IO ( PersistentCompilerState,
498 When the UnlinkedBCOExpr is linked you get an HValue of type
500 When you run it you get a list of HValues that should be
501 the same length as the list of names; add them to the ClosureEnv.
503 A naked expression returns a singleton Name [it].
505 What you type The IO [HValue] that hscStmt returns
506 ------------- ------------------------------------
507 let pat = expr ==> let pat = expr in return [coerce HVal x, coerce HVal y, ...]
510 pat <- expr ==> expr >>= \ pat -> return [coerce HVal x, coerce HVal y, ...]
513 expr (of IO type) ==> expr >>= \ v -> return [v]
514 [NB: result not printed] bindings: [it]
517 expr (of non-IO type,
518 result showable) ==> let v = expr in print v >> return [v]
521 expr (of non-IO type,
522 result not showable) ==> error
525 hscStmt dflags hst hit pcs0 icontext stmt just_expr
526 = do { maybe_stmt <- hscParseStmt dflags stmt
528 Nothing -> return (pcs0, Nothing)
529 Just parsed_stmt -> do {
531 let { notExprStmt (ExprStmt _ _ _) = False;
535 if (just_expr && notExprStmt parsed_stmt)
536 then do hPutStrLn stderr ("not an expression: `" ++ stmt ++ "'")
537 return (pcs0, Nothing)
541 (pcs1, print_unqual, maybe_renamed_stmt)
542 <- renameStmt dflags hit hst pcs0 icontext parsed_stmt
544 ; case maybe_renamed_stmt of
545 Nothing -> return (pcs0, Nothing)
546 Just (bound_names, rn_stmt) -> do {
551 then case rn_stmt of { (ExprStmt e _ _, decls) ->
552 typecheckExpr dflags pcs1 hst (ic_type_env icontext)
553 print_unqual iNTERACTIVE (e,decls) }
554 else typecheckStmt dflags pcs1 hst (ic_type_env icontext)
555 print_unqual iNTERACTIVE bound_names rn_stmt
557 ; case maybe_tc_return of
558 Nothing -> return (pcs0, Nothing)
559 Just (pcs2, tc_expr, bound_ids, ty) -> do {
562 ds_expr <- deSugarExpr dflags pcs2 hst iNTERACTIVE print_unqual tc_expr
565 ; flat_expr <- flattenExpr dflags pcs2 hst ds_expr
568 ; simpl_expr <- simplifyExpr dflags pcs2 hst flat_expr
570 -- Tidy it (temporary, until coreSat does cloning)
571 ; tidy_expr <- tidyCoreExpr simpl_expr
573 -- Prepare for codegen
574 ; prepd_expr <- corePrepExpr dflags tidy_expr
577 ; bcos <- coreExprToBCOs dflags prepd_expr
580 -- Make all the bound ids "global" ids, now that
581 -- they're notionally top-level bindings. This is
582 -- important: otherwise when we come to compile an expression
583 -- using these ids later, the byte code generator will consider
584 -- the occurrences to be free rather than global.
585 global_bound_ids = map globaliseId bound_ids;
586 globaliseId id = setGlobalIdDetails id VanillaGlobal
588 ; return (pcs2, Just (global_bound_ids, ty, bcos))
592 hscParseStmt :: DynFlags -> String -> IO (Maybe RdrNameStmt)
593 hscParseStmt dflags str
594 = do -------------------------- Parser ----------------
595 showPass dflags "Parser"
598 buf <- stringToStringBuffer str
600 let exts = ExtFlags {glasgowExtsEF = dopt Opt_GlasgowExts dflags,
601 parrEF = dopt Opt_PArr dflags}
602 loc = mkSrcLoc SLIT("<interactive>") 1
604 case parseStmt buf (mkPState loc exts) of {
606 PFailed err -> do { hPutStrLn stderr (showSDoc err);
607 -- Not yet implemented in <4.11 freeStringBuffer buf;
610 -- no stmt: the line consisted of just space or comments
611 POk _ Nothing -> return Nothing;
613 POk _ (Just rdr_stmt) -> do {
615 --ToDo: can't free the string buffer until we've finished this
616 -- compilation sweep and all the identifiers have gone away.
617 --freeStringBuffer buf;
618 dumpIfSet_dyn dflags Opt_D_dump_parsed "Parser" (ppr rdr_stmt);
619 return (Just rdr_stmt)
624 %************************************************************************
626 \subsection{Getting information about an identifer}
628 %************************************************************************
632 hscThing -- like hscStmt, but deals with a single identifier
636 -> PersistentCompilerState -- IN: persistent compiler state
637 -> InteractiveContext -- Context for compiling
638 -> String -- The identifier
639 -> IO ( PersistentCompilerState,
642 hscThing dflags hst hit pcs0 ic str
643 = do maybe_rdr_name <- myParseIdentifier dflags str
644 case maybe_rdr_name of {
645 Nothing -> return (pcs0, []);
648 -- if the identifier is a constructor (begins with an
649 -- upper-case letter), then we need to consider both
650 -- constructor and type class identifiers.
652 | occNameSpace occ == dataName = [ rdr_name, tccls_name ]
653 | otherwise = [ rdr_name ]
655 occ = rdrNameOcc rdr_name
656 tccls_occ = setOccNameSpace occ tcClsName
657 tccls_name = setRdrNameOcc rdr_name tccls_occ
659 (pcs, unqual, maybe_rn_result) <-
660 renameRdrName dflags hit hst pcs0 ic rdr_names
662 case maybe_rn_result of {
663 Nothing -> return (pcs, []);
664 Just (names, decls) -> do {
666 maybe_pcs <- typecheckExtraDecls dflags pcs hst unqual
670 Nothing -> return (pcs, []);
673 | isLocalName n = lookupNameEnv (ic_type_env ic) n
674 | otherwise = lookupType hst (pcs_PTE pcs) n
676 maybe_ty_things = map do_lookup names
678 return (pcs, catMaybes maybe_ty_things) }
681 myParseIdentifier dflags str
682 = do buf <- stringToStringBuffer str
684 let exts = ExtFlags {glasgowExtsEF = dopt Opt_GlasgowExts dflags,
685 parrEF = dopt Opt_PArr dflags}
686 loc = mkSrcLoc SLIT("<interactive>") 1
688 case parseIdentifier buf (mkPState loc exts) of
690 PFailed err -> do { hPutStrLn stderr (showSDoc err);
691 freeStringBuffer buf;
694 POk _ rdr_name -> do { --should, but can't: freeStringBuffer buf;
695 return (Just rdr_name) }
699 %************************************************************************
701 \subsection{Find all the things defined in a module}
703 %************************************************************************
711 -> PersistentCompilerState -- IN: persistent compiler state
712 -> Module -- module to inspect
713 -> Bool -- grab just the exports, or the whole toplev
714 -> IO (PersistentCompilerState, Maybe [TyThing])
716 hscModuleContents dflags hst hit pcs0 mod exports_only = do {
718 -- slurp the interface if necessary
719 (pcs1, print_unqual, maybe_rn_stuff)
720 <- slurpIface dflags hit hst pcs0 mod;
722 case maybe_rn_stuff of {
723 Nothing -> return (pcs0, Nothing);
724 Just (names, rn_decls) -> do {
726 -- Typecheck the declarations
728 typecheckExtraDecls dflags pcs1 hst print_unqual iNTERACTIVE rn_decls;
731 Nothing -> return (pcs1, Nothing);
735 | exports_only = names
737 let { iface = fromJust (lookupModuleEnv hit mod);
738 env = fromJust (mi_globals iface);
739 range = rdrEnvElts env;
741 -- grab all the things from the global env that are locally def'd
742 nub [ n | elts <- range, GRE n LocalDef _ <- elts ];
746 ty_things = map (fromJust . lookupType hst pte) all_names;
750 return (pcs2, Just ty_things)
755 %************************************************************************
757 \subsection{Initial persistent state}
759 %************************************************************************
762 initPersistentCompilerState :: IO PersistentCompilerState
763 initPersistentCompilerState
764 = do prs <- initPersistentRenamerState
766 PCS { pcs_PIT = emptyIfaceTable,
767 pcs_PTE = wiredInThingEnv,
768 pcs_insts = emptyInstEnv,
769 pcs_rules = emptyRuleBase,
774 initPersistentRenamerState :: IO PersistentRenamerState
775 = do us <- mkSplitUniqSupply 'r'
777 PRS { prsOrig = NameSupply { nsUniqs = us,
778 nsNames = initOrigNames,
780 prsDecls = (emptyNameEnv, 0),
781 prsInsts = (emptyBag, 0),
782 prsRules = foldr add_rule (emptyBag, 0) builtinRules,
787 add_rule (name,rule) (rules, n_rules)
788 = (gated_decl `consBag` rules, n_rules+1)
790 gated_decl = (gate_fn, (mod, IfaceRuleOut rdr_name rule))
791 mod = nameModule name
792 rdr_name = mkRdrOrig (moduleName mod) (nameOccName name)
793 gate_fn vis_fn = vis_fn name -- Load the rule whenever name is visible
795 initOrigNames :: FiniteMap (ModuleName,OccName) Name
797 = grab knownKeyNames `plusFM` grab (map getName wiredInThings)
799 grab names = foldl add emptyFM names
801 = addToFM env (moduleName (nameModule name), nameOccName name) name