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 TidyPgm ( 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 ( isInternalName )
30 import NameEnv ( lookupNameEnv )
31 import Module ( lookupModuleEnv )
32 import RdrName ( rdrEnvElts )
33 import PrelNames ( iNTERACTIVE )
34 import StringBuffer ( stringToStringBuffer )
35 import Maybes ( catMaybes )
42 import RdrName ( mkRdrOrig )
44 import IdInfo ( CafInfo(..), CgInfoEnv, CgInfo(..) )
45 import StringBuffer ( hGetStringBuffer, freeStringBuffer )
47 import Lex ( ParseResult(..), ExtFlags(..), mkPState )
48 import SrcLoc ( mkSrcLoc )
49 import Finder ( findModule )
50 import Rename ( checkOldIface, renameModule, closeIfaceDecls )
51 import Rules ( emptyRuleBase )
52 import PrelInfo ( wiredInThingEnv, wiredInThings )
53 import PrelRules ( builtinRules )
54 import PrelNames ( knownKeyNames, gHC_PRIM_Name )
55 import MkIface ( mkFinalIface )
57 import InstEnv ( emptyInstEnv )
59 import Flattening ( flatten, flattenExpr )
61 import CoreUtils ( coreBindsSize )
62 import TidyPgm ( tidyCorePgm )
63 import CorePrep ( corePrepPgm )
65 import CoreToStg ( coreToStg )
66 import SimplStg ( stg2stg )
67 import CodeGen ( codeGen )
68 import CodeOutput ( codeOutput, outputForeignStubs )
70 import Module ( ModuleName, moduleName, mkHomeModule )
72 import DriverState ( v_HCHeader )
73 import ErrUtils ( dumpIfSet_dyn, showPass, printError )
74 import Util ( unJust )
75 import UniqSupply ( mkSplitUniqSupply )
77 import Bag ( consBag, emptyBag )
79 import HscStats ( ppSourceStats )
81 import FiniteMap ( FiniteMap, plusFM, emptyFM, addToFM )
82 import OccName ( OccName )
83 import Name ( Name, nameModule, nameOccName, getName )
84 import NameEnv ( emptyNameEnv, mkNameEnv )
85 import Module ( Module )
87 import IOExts ( newIORef, readIORef, writeIORef,
91 import Maybe ( isJust, fromJust )
94 import MkExternalCore ( emitExternalCore )
96 import ParserCoreUtils
101 %************************************************************************
103 \subsection{The main compiler pipeline}
105 %************************************************************************
109 -- compilation failed
110 = HscFail PersistentCompilerState -- updated PCS
111 -- concluded that it wasn't necessary
112 | HscNoRecomp PersistentCompilerState -- updated PCS
113 ModDetails -- new details (HomeSymbolTable additions)
114 ModIface -- new iface (if any compilation was done)
116 | HscRecomp PersistentCompilerState -- updated PCS
117 ModDetails -- new details (HomeSymbolTable additions)
118 ModIface -- new iface (if any compilation was done)
119 Bool -- stub_h exists
120 Bool -- stub_c exists
122 (Maybe ([UnlinkedBCO],ItblEnv)) -- interpreted code, if any
124 (Maybe ()) -- no interpreted code whatsoever
127 -- no errors or warnings; the individual passes
128 -- (parse/rename/typecheck) print messages themselves
134 -> ModuleLocation -- location info
135 -> Bool -- True <=> source unchanged
136 -> Bool -- True <=> have an object file (for msgs only)
137 -> Maybe ModIface -- old interface, if available
138 -> HomeSymbolTable -- for home module ModDetails
140 -> PersistentCompilerState -- IN: persistent compiler state
143 hscMain ghci_mode dflags mod location source_unchanged have_object
144 maybe_old_iface hst hit pcs
145 = {-# SCC "hscMain" #-}
147 showPass dflags ("Checking old interface for hs = "
148 ++ show (ml_hs_file location)
149 ++ ", hspp = " ++ show (ml_hspp_file location));
151 (pcs_ch, errs_found, (recomp_reqd, maybe_checked_iface))
152 <- _scc_ "checkOldIface"
153 checkOldIface ghci_mode dflags hit hst pcs mod (ml_hi_file location)
154 source_unchanged maybe_old_iface;
157 return (HscFail pcs_ch)
160 let no_old_iface = not (isJust maybe_checked_iface)
161 what_next | recomp_reqd || no_old_iface = hscRecomp
162 | otherwise = hscNoRecomp
164 what_next ghci_mode dflags have_object mod location
165 maybe_checked_iface hst hit pcs_ch
169 -- we definitely expect to have the old interface available
170 hscNoRecomp ghci_mode dflags have_object
171 mod location (Just old_iface) hst hit pcs_ch
172 | ghci_mode == OneShot
174 when (verbosity dflags > 0) $
175 hPutStrLn stderr "compilation IS NOT required";
176 let { bomb = panic "hscNoRecomp:OneShot" };
177 return (HscNoRecomp pcs_ch bomb bomb)
181 when (verbosity dflags >= 1) $
182 hPutStrLn stderr ("Skipping " ++
183 showModMsg have_object mod location);
186 (pcs_cl, closure_errs, cl_hs_decls)
187 <- closeIfaceDecls dflags hit hst pcs_ch old_iface ;
189 return (HscFail pcs_cl)
194 <- typecheckIface dflags pcs_cl hst old_iface cl_hs_decls;
196 case maybe_tc_result of {
197 Nothing -> return (HscFail pcs_cl);
198 Just (pcs_tc, new_details) ->
200 return (HscNoRecomp pcs_tc new_details old_iface)
203 hscRecomp ghci_mode dflags have_object
204 mod location maybe_checked_iface hst hit pcs_ch
206 -- what target are we shooting for?
207 ; let toInterp = dopt_HscLang dflags == HscInterpreted
208 ; let toNothing = dopt_HscLang dflags == HscNothing
210 ; when (ghci_mode /= OneShot && verbosity dflags >= 1) $
211 hPutStrLn stderr ("Compiling " ++
212 showModMsg (not toInterp) mod location);
217 ; maybe_parsed <- myParseModule dflags
218 (unJust "hscRecomp:hspp" (ml_hspp_file location))
219 ; case maybe_parsed of {
220 Nothing -> return (HscFail pcs_ch);
221 Just rdr_module -> do {
222 ; let this_mod = mkHomeModule (hsModuleName rdr_module)
227 ; (pcs_rn, print_unqual, maybe_rn_result)
229 renameModule dflags ghci_mode hit hst pcs_ch this_mod rdr_module
230 ; case maybe_rn_result of {
231 Nothing -> return (HscFail pcs_ch);
232 Just (dont_discard, new_iface, rn_result) -> do {
239 typecheckModule dflags pcs_rn hst print_unqual rn_result
240 ; case maybe_tc_result of {
241 Nothing -> return (HscFail pcs_ch);
242 Just (pcs_tc, tc_result) -> do {
247 ; (ds_details, foreign_stuff)
249 deSugar dflags pcs_tc hst this_mod print_unqual tc_result
255 <- _scc_ "Flattening"
256 flatten dflags pcs_tc hst ds_details
259 <- _scc_ "pcs_middle"
260 if ghci_mode == OneShot
261 then do init_pcs <- initPersistentCompilerState
262 init_prs <- initPersistentRenamerState
264 rules = pcs_rules pcs_tc
265 orig_tc = prsOrig (pcs_PRS pcs_tc)
266 new_prs = init_prs{ prsOrig=orig_tc }
268 orig_tc `seq` rules `seq` new_prs `seq`
269 return init_pcs{ pcs_PRS = new_prs,
273 -- alive at this point:
284 core2core dflags pcs_middle hst dont_discard flat_details
289 ; cg_info_ref <- newIORef Nothing ;
290 ; let cg_info :: CgInfoEnv
291 cg_info = unsafePerformIO $ do {
292 maybe_cg_env <- readIORef cg_info_ref ;
294 Just env -> return env
295 Nothing -> do { printError "Urk! Looked at CgInfo too early!";
296 return emptyNameEnv } }
297 -- cg_info_ref will be filled in just after restOfCodeGeneration
298 -- Meanwhile, tidyCorePgm is careful not to look at cg_info!
300 ; (pcs_simpl, tidy_details)
302 tidyCorePgm dflags this_mod pcs_middle cg_info simpl_details
304 ; pcs_final <- if ghci_mode == OneShot then initPersistentCompilerState
305 else return pcs_simpl
307 -- alive at this point:
311 ; emitExternalCore dflags new_iface tidy_details
313 ; let final_details = tidy_details {md_binds = []}
314 ; final_details `seq` return ()
317 -- PREPARE FOR CODE GENERATION
319 -- Do saturation and convert to A-normal form
320 ; prepd_details <- _scc_ "CorePrep"
321 corePrepPgm dflags tidy_details
324 -- CONVERT TO STG and COMPLETE CODE GENERATION
327 ModDetails{md_binds=binds, md_types=env_tc} = prepd_details
329 local_tycons = typeEnvTyCons env_tc
330 local_classes = typeEnvClasses env_tc
332 imported_module_names =
333 filter (/= gHC_PRIM_Name) $
334 map ideclName (hsModuleImports rdr_module)
335 -- eek! doesn't this keep rdr_module live until code generation?
338 mod_name_to_Module nm
339 = do m <- findModule nm ; return (fst (fromJust m))
341 (h_code, c_code, headers, fe_binders) = foreign_stuff
343 -- turn the list of headers requested in foreign import
344 -- declarations into a string suitable for emission into generated
349 . map (\fname -> "#include \"" ++ _UNPK_ fname ++ "\"")
353 -- ...and add the string to the headers requested via command line
356 ; fhdrs <- readIORef v_HCHeader
357 ; writeIORef v_HCHeader (fhdrs ++ foreign_headers)
359 ; imported_modules <- mapM mod_name_to_Module imported_module_names
361 ; (stub_h_exists, stub_c_exists, maybe_bcos, final_iface )
365 ----------------- Generate byte code ------------------
366 (bcos,itbl_env) <- byteCodeGen dflags binds
367 local_tycons local_classes
369 -- Fill in the code-gen info
370 writeIORef cg_info_ref (Just emptyNameEnv)
372 ------------------ BUILD THE NEW ModIface ------------
373 final_iface <- _scc_ "MkFinalIface"
374 mkFinalIface ghci_mode dflags location
375 maybe_checked_iface new_iface tidy_details
377 ------------------ Create f-x-dynamic C-side stuff ---
378 (istub_h_exists, istub_c_exists)
379 <- outputForeignStubs dflags c_code h_code
381 return ( istub_h_exists, istub_c_exists,
382 Just (bcos,itbl_env), final_iface )
384 then error "GHC not compiled with interpreter"
388 ----------------- Convert to STG ------------------
389 (stg_binds, cost_centre_info, stg_back_end_info)
391 myCoreToStg dflags this_mod binds
393 -- Fill in the code-gen info for the earlier tidyCorePgm
394 writeIORef cg_info_ref (Just stg_back_end_info)
396 ------------------ BUILD THE NEW ModIface ------------
397 final_iface <- _scc_ "MkFinalIface"
398 mkFinalIface ghci_mode dflags location
399 maybe_checked_iface new_iface tidy_details
402 return (False, False, Nothing, final_iface)
404 ------------------ Code generation ------------------
405 abstractC <- _scc_ "CodeGen"
406 codeGen dflags this_mod imported_modules
407 cost_centre_info fe_binders
408 local_tycons stg_binds
410 ------------------ Code output -----------------------
411 (stub_h_exists, stub_c_exists)
412 <- codeOutput dflags this_mod [] --local_tycons
414 c_code h_code abstractC
416 return (stub_h_exists, stub_c_exists, Nothing, final_iface)
418 -- and the answer is ...
419 ; return (HscRecomp pcs_final
422 stub_h_exists stub_c_exists
426 myParseModule dflags src_filename
427 = do -------------------------- Parser ----------------
428 showPass dflags "Parser"
430 if dopt_HscLang dflags == HscCore
432 inp <- readFile src_filename
433 case parseCore inp 1 of
434 OkP m -> return (Just m)
435 FailP s -> hPutStrLn stderr s >> return Nothing
437 buf <- hGetStringBuffer src_filename
439 let exts = ExtFlags {glasgowExtsEF = dopt Opt_GlasgowExts dflags,
440 parrEF = dopt Opt_PArr dflags}
441 loc = mkSrcLoc (_PK_ src_filename) 1
443 case parseModule buf (mkPState loc exts) of {
445 PFailed err -> do { hPutStrLn stderr (showSDoc err);
446 freeStringBuffer buf;
449 POk _ rdr_module@(HsModule mod_name _ _ _ _ _ _) -> do {
451 dumpIfSet_dyn dflags Opt_D_dump_parsed "Parser" (ppr rdr_module) ;
453 dumpIfSet_dyn dflags Opt_D_source_stats "Source Statistics"
454 (ppSourceStats False rdr_module) ;
456 return (Just rdr_module)
457 -- ToDo: free the string buffer later.
461 myCoreToStg dflags this_mod tidy_binds
463 () <- coreBindsSize tidy_binds `seq` return ()
464 -- TEMP: the above call zaps some space usage allocated by the
465 -- simplifier, which for reasons I don't understand, persists
466 -- thoroughout code generation -- JRS
468 -- This is still necessary. -- SDM (10 Dec 2001)
470 stg_binds <- _scc_ "Core2Stg"
471 coreToStg dflags tidy_binds
473 (stg_binds2, cost_centre_info) <- _scc_ "Core2Stg"
474 stg2stg dflags this_mod stg_binds
476 let env_rhs :: CgInfoEnv
477 env_rhs = mkNameEnv [ caf_info `seq` (idName bndr, CgInfo caf_info)
478 | (bind,_) <- stg_binds2,
480 | stgBindHasCafRefs bind = MayHaveCafRefs
481 | otherwise = NoCafRefs,
482 bndr <- stgBinders bind ]
484 return (stg_binds2, cost_centre_info, env_rhs)
488 %************************************************************************
490 \subsection{Compiling a do-statement}
492 %************************************************************************
500 -> PersistentCompilerState -- IN: persistent compiler state
501 -> InteractiveContext -- Context for compiling
502 -> String -- The statement
503 -> Bool -- just treat it as an expression
504 -> IO ( PersistentCompilerState,
510 When the UnlinkedBCOExpr is linked you get an HValue of type
512 When you run it you get a list of HValues that should be
513 the same length as the list of names; add them to the ClosureEnv.
515 A naked expression returns a singleton Name [it].
517 What you type The IO [HValue] that hscStmt returns
518 ------------- ------------------------------------
519 let pat = expr ==> let pat = expr in return [coerce HVal x, coerce HVal y, ...]
522 pat <- expr ==> expr >>= \ pat -> return [coerce HVal x, coerce HVal y, ...]
525 expr (of IO type) ==> expr >>= \ v -> return [v]
526 [NB: result not printed] bindings: [it]
529 expr (of non-IO type,
530 result showable) ==> let v = expr in print v >> return [v]
533 expr (of non-IO type,
534 result not showable) ==> error
537 hscStmt dflags hst hit pcs0 icontext stmt just_expr
538 = do { maybe_stmt <- hscParseStmt dflags stmt
540 Nothing -> return (pcs0, Nothing)
541 Just parsed_stmt -> do {
543 let { notExprStmt (ExprStmt _ _ _) = False;
547 if (just_expr && notExprStmt parsed_stmt)
548 then do hPutStrLn stderr ("not an expression: `" ++ stmt ++ "'")
549 return (pcs0, Nothing)
553 (pcs1, print_unqual, maybe_renamed_stmt)
554 <- renameStmt dflags hit hst pcs0 icontext parsed_stmt
556 ; case maybe_renamed_stmt of
557 Nothing -> return (pcs0, Nothing)
558 Just (bound_names, rn_stmt) -> do {
563 then case rn_stmt of { (ExprStmt e _ _, decls) ->
564 typecheckExpr dflags pcs1 hst (ic_type_env icontext)
565 print_unqual iNTERACTIVE (e,decls) }
566 else typecheckStmt dflags pcs1 hst (ic_type_env icontext)
567 print_unqual iNTERACTIVE bound_names rn_stmt
569 ; case maybe_tc_return of
570 Nothing -> return (pcs0, Nothing)
571 Just (pcs2, tc_expr, bound_ids, ty) -> do {
574 ds_expr <- deSugarExpr dflags pcs2 hst iNTERACTIVE print_unqual tc_expr
577 ; flat_expr <- flattenExpr dflags pcs2 hst ds_expr
580 ; simpl_expr <- simplifyExpr dflags pcs2 hst flat_expr
582 -- Tidy it (temporary, until coreSat does cloning)
583 ; tidy_expr <- tidyCoreExpr simpl_expr
585 -- Prepare for codegen
586 ; prepd_expr <- corePrepExpr dflags tidy_expr
589 ; bcos <- coreExprToBCOs dflags prepd_expr
592 -- Make all the bound ids "global" ids, now that
593 -- they're notionally top-level bindings. This is
594 -- important: otherwise when we come to compile an expression
595 -- using these ids later, the byte code generator will consider
596 -- the occurrences to be free rather than global.
597 global_bound_ids = map globaliseId bound_ids;
598 globaliseId id = setGlobalIdDetails id VanillaGlobal
600 ; return (pcs2, Just (global_bound_ids, ty, bcos))
604 hscParseStmt :: DynFlags -> String -> IO (Maybe RdrNameStmt)
605 hscParseStmt dflags str
606 = do -------------------------- Parser ----------------
607 showPass dflags "Parser"
610 buf <- stringToStringBuffer str
612 let exts = ExtFlags {glasgowExtsEF = dopt Opt_GlasgowExts dflags,
613 parrEF = dopt Opt_PArr dflags}
614 loc = mkSrcLoc SLIT("<interactive>") 1
616 case parseStmt buf (mkPState loc exts) of {
618 PFailed err -> do { hPutStrLn stderr (showSDoc err);
619 -- Not yet implemented in <4.11 freeStringBuffer buf;
622 -- no stmt: the line consisted of just space or comments
623 POk _ Nothing -> return Nothing;
625 POk _ (Just rdr_stmt) -> do {
627 --ToDo: can't free the string buffer until we've finished this
628 -- compilation sweep and all the identifiers have gone away.
629 --freeStringBuffer buf;
630 dumpIfSet_dyn dflags Opt_D_dump_parsed "Parser" (ppr rdr_stmt);
631 return (Just rdr_stmt)
636 %************************************************************************
638 \subsection{Getting information about an identifer}
640 %************************************************************************
644 hscThing -- like hscStmt, but deals with a single identifier
648 -> PersistentCompilerState -- IN: persistent compiler state
649 -> InteractiveContext -- Context for compiling
650 -> String -- The identifier
651 -> IO ( PersistentCompilerState,
654 hscThing dflags hst hit pcs0 ic str
655 = do maybe_rdr_name <- myParseIdentifier dflags str
656 case maybe_rdr_name of {
657 Nothing -> return (pcs0, []);
660 -- if the identifier is a constructor (begins with an
661 -- upper-case letter), then we need to consider both
662 -- constructor and type class identifiers.
664 | occNameSpace occ == dataName = [ rdr_name, tccls_name ]
665 | otherwise = [ rdr_name ]
667 occ = rdrNameOcc rdr_name
668 tccls_occ = setOccNameSpace occ tcClsName
669 tccls_name = setRdrNameOcc rdr_name tccls_occ
671 (pcs, unqual, maybe_rn_result) <-
672 renameRdrName dflags hit hst pcs0 ic rdr_names
674 case maybe_rn_result of {
675 Nothing -> return (pcs, []);
676 Just (names, decls) -> do {
678 maybe_pcs <- typecheckExtraDecls dflags pcs hst unqual
682 Nothing -> return (pcs, []);
685 | isInternalName n = lookupNameEnv (ic_type_env ic) n
686 | otherwise = lookupType hst (pcs_PTE pcs) n
688 maybe_ty_things = map do_lookup names
690 return (pcs, catMaybes maybe_ty_things) }
693 myParseIdentifier dflags str
694 = do buf <- stringToStringBuffer str
696 let exts = ExtFlags {glasgowExtsEF = dopt Opt_GlasgowExts dflags,
697 parrEF = dopt Opt_PArr dflags}
698 loc = mkSrcLoc SLIT("<interactive>") 1
700 case parseIdentifier buf (mkPState loc exts) of
702 PFailed err -> do { hPutStrLn stderr (showSDoc err);
703 freeStringBuffer buf;
706 POk _ rdr_name -> do { --should, but can't: freeStringBuffer buf;
707 return (Just rdr_name) }
711 %************************************************************************
713 \subsection{Find all the things defined in a module}
715 %************************************************************************
723 -> PersistentCompilerState -- IN: persistent compiler state
724 -> Module -- module to inspect
725 -> Bool -- grab just the exports, or the whole toplev
726 -> IO (PersistentCompilerState, Maybe [TyThing])
728 hscModuleContents dflags hst hit pcs0 mod exports_only = do {
730 -- slurp the interface if necessary
731 (pcs1, print_unqual, maybe_rn_stuff)
732 <- slurpIface dflags hit hst pcs0 mod;
734 case maybe_rn_stuff of {
735 Nothing -> return (pcs0, Nothing);
736 Just (names, rn_decls) -> do {
738 -- Typecheck the declarations
740 typecheckExtraDecls dflags pcs1 hst print_unqual iNTERACTIVE rn_decls;
743 Nothing -> return (pcs1, Nothing);
747 | exports_only = names
749 let { iface = fromJust (lookupModuleEnv hit mod);
750 env = fromJust (mi_globals iface);
751 range = rdrEnvElts env;
753 -- grab all the things from the global env that are locally def'd
754 nub [ n | elts <- range, GRE n LocalDef _ <- elts ];
758 ty_things = map (fromJust . lookupType hst pte) all_names;
762 return (pcs2, Just ty_things)
767 %************************************************************************
769 \subsection{Initial persistent state}
771 %************************************************************************
774 initPersistentCompilerState :: IO PersistentCompilerState
775 initPersistentCompilerState
776 = do prs <- initPersistentRenamerState
778 PCS { pcs_PIT = emptyIfaceTable,
779 pcs_PTE = wiredInThingEnv,
780 pcs_insts = emptyInstEnv,
781 pcs_rules = emptyRuleBase,
786 initPersistentRenamerState :: IO PersistentRenamerState
787 = do us <- mkSplitUniqSupply 'r'
789 PRS { prsOrig = NameSupply { nsUniqs = us,
790 nsNames = initOrigNames,
792 prsDecls = (emptyNameEnv, 0),
793 prsInsts = (emptyBag, 0),
794 prsRules = foldr add_rule (emptyBag, 0) builtinRules,
799 add_rule (name,rule) (rules, n_rules)
800 = (gated_decl `consBag` rules, n_rules+1)
802 gated_decl = (gate_fn, (mod, IfaceRuleOut rdr_name rule))
803 mod = nameModule name
804 rdr_name = mkRdrOrig (moduleName mod) (nameOccName name)
805 gate_fn vis_fn = vis_fn name -- Load the rule whenever name is visible
807 initOrigNames :: FiniteMap (ModuleName,OccName) Name
809 = grab knownKeyNames `plusFM` grab (map getName wiredInThings)
811 grab names = foldl add emptyFM names
813 = addToFM env (moduleName (nameModule name), nameOccName name) name