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,
12 initPersistentCompilerState ) where
14 #include "HsVersions.h"
17 import ByteCodeGen ( byteCodeGen )
18 import CoreTidy ( tidyCoreExpr )
19 import CorePrep ( corePrepExpr )
20 import SrcLoc ( noSrcLoc )
21 import Rename ( renameStmt )
22 import RdrName ( mkUnqual )
23 import RdrHsSyn ( RdrNameStmt )
24 import OccName ( dataName )
26 import Id ( Id, idName, setGlobalIdDetails )
27 import IdInfo ( GlobalIdDetails(VanillaGlobal) )
28 import HscTypes ( InteractiveContext(..) )
29 import PrelNames ( iNTERACTIVE )
30 import StringBuffer ( stringToStringBuffer )
31 import FastString ( mkFastString )
37 import IdInfo ( CafInfo(..), CgInfoEnv, CgInfo(..) )
38 import StringBuffer ( hGetStringBuffer, freeStringBuffer )
40 import Lex ( PState(..), ParseResult(..) )
41 import SrcLoc ( mkSrcLoc )
42 import Finder ( findModule )
43 import Rename ( checkOldIface, renameModule, closeIfaceDecls )
44 import Rules ( emptyRuleBase )
45 import PrelInfo ( wiredInThingEnv, wiredInThings )
46 import PrelNames ( knownKeyNames )
47 import MkIface ( mkFinalIface )
49 import InstEnv ( emptyInstEnv )
52 import CoreUtils ( coreBindsSize )
53 import CoreTidy ( tidyCorePgm )
54 import CorePrep ( corePrepPgm )
56 import CoreToStg ( coreToStg )
57 import SimplStg ( stg2stg )
58 import CodeGen ( codeGen )
59 import CodeOutput ( codeOutput )
61 import Module ( ModuleName, moduleName, mkHomeModule,
64 import ErrUtils ( dumpIfSet_dyn, showPass, printError )
65 import Util ( unJust )
66 import UniqSupply ( mkSplitUniqSupply )
68 import Bag ( emptyBag )
71 import HscStats ( ppSourceStats )
73 import FiniteMap ( FiniteMap, plusFM, emptyFM, addToFM )
74 import OccName ( OccName )
75 import Name ( Name, nameModule, nameOccName, getName, isGlobalName )
76 import NameEnv ( emptyNameEnv, mkNameEnv )
77 import Module ( Module )
79 import IOExts ( newIORef, readIORef, writeIORef, unsafePerformIO )
82 import Maybe ( isJust, fromJust )
85 import MkExternalCore ( emitExternalCore )
89 %************************************************************************
91 \subsection{The main compiler pipeline}
93 %************************************************************************
98 = HscFail PersistentCompilerState -- updated PCS
99 -- concluded that it wasn't necessary
100 | HscNoRecomp PersistentCompilerState -- updated PCS
101 ModDetails -- new details (HomeSymbolTable additions)
102 ModIface -- new iface (if any compilation was done)
104 | HscRecomp PersistentCompilerState -- updated PCS
105 ModDetails -- new details (HomeSymbolTable additions)
106 ModIface -- new iface (if any compilation was done)
107 Bool -- stub_h exists
108 Bool -- stub_c exists
110 (Maybe ([UnlinkedBCO],ItblEnv)) -- interpreted code, if any
112 (Maybe ()) -- no interpreted code whatsoever
115 -- no errors or warnings; the individual passes
116 -- (parse/rename/typecheck) print messages themselves
122 -> ModuleLocation -- location info
123 -> Bool -- True <=> source unchanged
124 -> Bool -- True <=> have an object file (for msgs only)
125 -> Maybe ModIface -- old interface, if available
126 -> HomeSymbolTable -- for home module ModDetails
128 -> PersistentCompilerState -- IN: persistent compiler state
131 hscMain ghci_mode dflags mod location source_unchanged have_object
132 maybe_old_iface hst hit pcs
134 showPass dflags ("Checking old interface for hs = "
135 ++ show (ml_hs_file location)
136 ++ ", hspp = " ++ show (ml_hspp_file location));
138 (pcs_ch, errs_found, (recomp_reqd, maybe_checked_iface))
139 <- _scc_ "checkOldIface"
140 checkOldIface ghci_mode dflags hit hst pcs (ml_hi_file location)
141 source_unchanged maybe_old_iface;
144 return (HscFail pcs_ch)
147 let no_old_iface = not (isJust maybe_checked_iface)
148 what_next | recomp_reqd || no_old_iface = hscRecomp
149 | otherwise = hscNoRecomp
151 what_next ghci_mode dflags have_object mod location
152 maybe_checked_iface hst hit pcs_ch
156 -- we definitely expect to have the old interface available
157 hscNoRecomp ghci_mode dflags have_object
158 mod location (Just old_iface) hst hit pcs_ch
159 | ghci_mode == OneShot
161 hPutStrLn stderr "compilation IS NOT required";
162 let { bomb = panic "hscNoRecomp:OneShot" };
163 return (HscNoRecomp pcs_ch bomb bomb)
167 when (verbosity dflags >= 1) $
168 hPutStrLn stderr ("Skipping " ++
169 compMsg have_object mod location);
172 (pcs_cl, closure_errs, cl_hs_decls)
173 <- closeIfaceDecls dflags hit hst pcs_ch old_iface ;
175 return (HscFail pcs_cl)
180 <- typecheckIface dflags pcs_cl hst old_iface cl_hs_decls;
182 case maybe_tc_result of {
183 Nothing -> return (HscFail pcs_cl);
184 Just (pcs_tc, new_details) ->
186 return (HscNoRecomp pcs_tc new_details old_iface)
189 compMsg use_object mod location =
190 mod_str ++ take (max 0 (16 - length mod_str)) (repeat ' ')
191 ++" ( " ++ unJust "hscRecomp" (ml_hs_file location) ++ ", "
193 then unJust "hscRecomp" (ml_obj_file location)
196 where mod_str = moduleUserString mod
199 hscRecomp ghci_mode dflags have_object
200 mod location maybe_checked_iface hst hit pcs_ch
202 -- what target are we shooting for?
203 ; let toInterp = dopt_HscLang dflags == HscInterpreted
205 ; when (verbosity dflags >= 1) $
206 hPutStrLn stderr ("Compiling " ++
207 compMsg (not toInterp) mod location);
212 ; maybe_parsed <- myParseModule dflags
213 (unJust "hscRecomp:hspp" (ml_hspp_file location))
214 ; case maybe_parsed of {
215 Nothing -> return (HscFail pcs_ch);
216 Just rdr_module -> do {
217 ; let this_mod = mkHomeModule (hsModuleName rdr_module)
222 ; (pcs_rn, print_unqualified, maybe_rn_result)
224 renameModule dflags hit hst pcs_ch this_mod rdr_module
225 ; case maybe_rn_result of {
226 Nothing -> return (HscFail pcs_ch{-was: pcs_rn-});
227 Just (is_exported, new_iface, rn_hs_decls) -> do {
229 -- In interactive mode, we don't want to discard any top-level entities at
230 -- all (eg. do not inline them away during simplification), and retain them
231 -- all in the TypeEnv so they are available from the command line.
233 -- isGlobalName separates the user-defined top-level names from those
234 -- introduced by the type checker.
235 ; let dont_discard | ghci_mode == Interactive = isGlobalName
236 | otherwise = is_exported
242 <- _scc_ "TypeCheck" typecheckModule dflags pcs_rn hst new_iface
243 print_unqualified rn_hs_decls
244 ; case maybe_tc_result of {
245 Nothing -> return (HscFail pcs_ch{-was: pcs_rn-});
246 Just (pcs_tc, tc_result) -> do {
251 ; (ds_details, foreign_stuff)
253 deSugar dflags pcs_tc hst this_mod print_unqualified tc_result
256 <- if ghci_mode == OneShot
257 then do init_pcs <- initPersistentCompilerState
258 init_prs <- initPersistentRenamerState
260 rules = pcs_rules pcs_tc
261 orig_tc = prsOrig (pcs_PRS pcs_tc)
262 new_prs = init_prs{ prsOrig=orig_tc }
264 orig_tc `seq` rules `seq` new_prs `seq`
265 return init_pcs{ pcs_PRS = new_prs,
274 core2core dflags pcs_middle hst dont_discard ds_details
279 ; cg_info_ref <- newIORef Nothing ;
280 ; let cg_info :: CgInfoEnv
281 cg_info = unsafePerformIO $ do {
282 maybe_cg_env <- readIORef cg_info_ref ;
284 Just env -> return env
285 Nothing -> do { printError "Urk! Looked at CgInfo too early!";
286 return emptyNameEnv } }
287 -- cg_info_ref will be filled in just after restOfCodeGeneration
288 -- Meanwhile, tidyCorePgm is careful not to look at cg_info!
290 ; (pcs_simpl, tidy_details)
292 tidyCorePgm dflags this_mod pcs_middle cg_info simpl_details
294 ; pcs_final <- if ghci_mode == OneShot then initPersistentCompilerState
295 else return pcs_simpl
297 -- alive at this point:
301 ; emitExternalCore dflags new_iface tidy_details
303 -- PREPARE FOR CODE GENERATION
305 -- Do saturation and convert to A-normal form
306 ; prepd_details <- _scc_ "CorePrep" corePrepPgm dflags tidy_details
309 -- CONVERT TO STG and COMPLETE CODE GENERATION
312 ModDetails{md_binds=binds, md_types=env_tc} = prepd_details
314 local_tycons = typeEnvTyCons env_tc
315 local_classes = typeEnvClasses env_tc
317 imported_module_names = map ideclName (hsModuleImports rdr_module)
319 mod_name_to_Module nm
320 = do m <- findModule nm ; return (fst (fromJust m))
322 (h_code,c_code,fe_binders) = foreign_stuff
324 ; imported_modules <- mapM mod_name_to_Module imported_module_names
326 ; (stub_h_exists, stub_c_exists, maybe_bcos, final_iface )
330 ----------------- Generate byte code ------------------
331 (bcos,itbl_env) <- byteCodeGen dflags binds
332 local_tycons local_classes
334 -- Fill in the code-gen info
335 writeIORef cg_info_ref (Just emptyNameEnv)
337 ------------------ BUILD THE NEW ModIface ------------
338 final_iface <- _scc_ "MkFinalIface"
339 mkFinalIface ghci_mode dflags location
340 maybe_checked_iface new_iface tidy_details
342 return ( False, False, Just (bcos,itbl_env), final_iface )
344 then error "GHC not compiled with interpreter"
348 ----------------- Convert to STG ------------------
349 (stg_binds, cost_centre_info, stg_back_end_info)
351 myCoreToStg dflags this_mod binds
353 -- Fill in the code-gen info for the earlier tidyCorePgm
354 writeIORef cg_info_ref (Just stg_back_end_info)
356 ------------------ BUILD THE NEW ModIface ------------
357 final_iface <- _scc_ "MkFinalIface"
358 mkFinalIface ghci_mode dflags location
359 maybe_checked_iface new_iface tidy_details
361 ------------------ Code generation ------------------
362 abstractC <- _scc_ "CodeGen"
363 codeGen dflags this_mod imported_modules
364 cost_centre_info fe_binders
365 local_tycons stg_binds
367 ------------------ Code output -----------------------
368 (stub_h_exists, stub_c_exists)
369 <- codeOutput dflags this_mod local_tycons
371 c_code h_code abstractC
373 return (stub_h_exists, stub_c_exists, Nothing, final_iface)
375 ; let final_details = tidy_details {md_binds = []}
378 -- and the answer is ...
379 ; return (HscRecomp pcs_final
382 stub_h_exists stub_c_exists
386 myParseModule dflags src_filename
387 = do -------------------------- Parser ----------------
388 showPass dflags "Parser"
391 buf <- hGetStringBuffer True{-expand tabs-} src_filename
393 let glaexts | dopt Opt_GlasgowExts dflags = 1#
396 case parseModule buf PState{ bol = 0#, atbol = 1#,
397 context = [], glasgow_exts = glaexts,
398 loc = mkSrcLoc (_PK_ src_filename) 1 } of {
400 PFailed err -> do { hPutStrLn stderr (showSDoc err);
401 freeStringBuffer buf;
404 POk _ rdr_module@(HsModule mod_name _ _ _ _ _ _) -> do {
406 dumpIfSet_dyn dflags Opt_D_dump_parsed "Parser" (ppr rdr_module) ;
408 dumpIfSet_dyn dflags Opt_D_source_stats "Source Statistics"
409 (ppSourceStats False rdr_module) ;
411 return (Just rdr_module)
412 -- ToDo: free the string buffer later.
416 myCoreToStg dflags this_mod tidy_binds
418 () <- coreBindsSize tidy_binds `seq` return ()
419 -- TEMP: the above call zaps some space usage allocated by the
420 -- simplifier, which for reasons I don't understand, persists
421 -- thoroughout code generation
423 stg_binds <- _scc_ "Core2Stg" coreToStg dflags tidy_binds
425 (stg_binds2, cost_centre_info)
426 <- _scc_ "Core2Stg" stg2stg dflags this_mod stg_binds
428 let env_rhs :: CgInfoEnv
429 env_rhs = mkNameEnv [ (idName bndr, CgInfo (stgRhsArity rhs) caf_info)
430 | (bind,_) <- stg_binds2,
432 | stgBindHasCafRefs bind = MayHaveCafRefs
433 | otherwise = NoCafRefs,
434 (bndr,rhs) <- stgBindPairs bind ]
436 return (stg_binds2, cost_centre_info, env_rhs)
438 stgBindPairs (StgNonRec _ b r) = [(b,r)]
439 stgBindPairs (StgRec _ prs) = prs
445 %************************************************************************
447 \subsection{Compiling a do-statement}
449 %************************************************************************
457 -> PersistentCompilerState -- IN: persistent compiler state
458 -> InteractiveContext -- Context for compiling
459 -> String -- The statement
460 -> Bool -- just treat it as an expression
461 -> IO ( PersistentCompilerState,
467 When the UnlinkedBCOExpr is linked you get an HValue of type
469 When you run it you get a list of HValues that should be
470 the same length as the list of names; add them to the ClosureEnv.
472 A naked expression returns a singleton Name [it].
474 What you type The IO [HValue] that hscStmt returns
475 ------------- ------------------------------------
476 let pat = expr ==> let pat = expr in return [coerce HVal x, coerce HVal y, ...]
479 pat <- expr ==> expr >>= \ pat -> return [coerce HVal x, coerce HVal y, ...]
482 expr (of IO type) ==> expr >>= \ v -> return [v]
483 [NB: result not printed] bindings: [it]
486 expr (of non-IO type,
487 result showable) ==> let v = expr in print v >> return [v]
490 expr (of non-IO type,
491 result not showable) ==> error
494 hscStmt dflags hst hit pcs0 icontext stmt just_expr
498 ic_type_env = type_env,
499 ic_module = scope_mod } = icontext
501 do { maybe_stmt <- hscParseStmt dflags stmt
503 Nothing -> return (pcs0, Nothing)
504 Just parsed_stmt -> do {
506 let { notExprStmt (ExprStmt _ _ _) = False;
510 if (just_expr && notExprStmt parsed_stmt)
511 then do hPutStrLn stderr ("not an expression: `" ++ stmt ++ "'")
512 return (pcs0, Nothing)
516 (pcs1, print_unqual, maybe_renamed_stmt)
517 <- renameStmt dflags hit hst pcs0 scope_mod
518 iNTERACTIVE rn_env parsed_stmt
520 ; case maybe_renamed_stmt of
521 Nothing -> return (pcs0, Nothing)
522 Just (bound_names, rn_stmt) -> do {
527 then case rn_stmt of { (ExprStmt e _ _, decls) ->
528 typecheckExpr dflags pcs1 hst type_env
529 print_unqual iNTERACTIVE (e,decls) }
530 else typecheckStmt dflags pcs1 hst type_env
531 print_unqual iNTERACTIVE bound_names rn_stmt
533 ; case maybe_tc_return of
534 Nothing -> return (pcs0, Nothing)
535 Just (pcs2, tc_expr, bound_ids, ty) -> do {
538 ds_expr <- deSugarExpr dflags pcs2 hst iNTERACTIVE print_unqual tc_expr
541 ; simpl_expr <- simplifyExpr dflags pcs2 hst ds_expr
543 -- Tidy it (temporary, until coreSat does cloning)
544 ; tidy_expr <- tidyCoreExpr simpl_expr
546 -- Prepare for codegen
547 ; prepd_expr <- corePrepExpr dflags tidy_expr
550 ; bcos <- coreExprToBCOs dflags prepd_expr
553 -- Make all the bound ids "global" ids, now that
554 -- they're notionally top-level bindings. This is
555 -- important: otherwise when we come to compile an expression
556 -- using these ids later, the byte code generator will consider
557 -- the occurrences to be free rather than global.
558 global_bound_ids = map globaliseId bound_ids;
559 globaliseId id = setGlobalIdDetails id VanillaGlobal
561 ; return (pcs2, Just (global_bound_ids, ty, bcos))
565 hscThing -- like hscStmt, but deals with a single identifier
569 -> PersistentCompilerState -- IN: persistent compiler state
570 -> InteractiveContext -- Context for compiling
571 -> String -- The identifier
572 -> IO ( PersistentCompilerState,
574 hscThing dflags hst hit pcs0 icontext id
578 ic_type_env = type_env,
579 ic_module = scope_mod } = icontext
580 fname = mkFastString id
581 rn = mkUnqual dataName fname -- need to guess correct namespace
582 stmt = ResultStmt (HsVar rn) noSrcLoc
584 do { (pcs, err, maybe_stmt) <- renameStmt dflags hit hst pcs0 scope_mod scope_mod rn_env stmt
586 Nothing -> return (pcs, Nothing)
587 Just (n:ns, _) -> return (pcs, lookupType hst type_env n)
590 hscParseStmt :: DynFlags -> String -> IO (Maybe RdrNameStmt)
591 hscParseStmt dflags str
592 = do -------------------------- Parser ----------------
593 showPass dflags "Parser"
596 buf <- stringToStringBuffer str
598 let glaexts | dopt Opt_GlasgowExts dflags = 1#
601 case parseStmt buf PState{ bol = 0#, atbol = 1#,
602 context = [], glasgow_exts = glaexts,
603 loc = mkSrcLoc SLIT("<no file>") 0 } of {
605 PFailed err -> do { hPutStrLn stderr (showSDoc err);
606 -- Not yet implemented in <4.11 freeStringBuffer buf;
609 -- no stmt: the line consisted of just space or comments
610 POk _ Nothing -> return Nothing;
612 POk _ (Just rdr_stmt) -> do {
614 --ToDo: can't free the string buffer until we've finished this
615 -- compilation sweep and all the identifiers have gone away.
616 --freeStringBuffer buf;
617 dumpIfSet_dyn dflags Opt_D_dump_parsed "Parser" (ppr rdr_stmt);
618 return (Just rdr_stmt)
623 %************************************************************************
625 \subsection{Initial persistent state}
627 %************************************************************************
630 initPersistentCompilerState :: IO PersistentCompilerState
631 initPersistentCompilerState
632 = do prs <- initPersistentRenamerState
634 PCS { pcs_PIT = emptyIfaceTable,
635 pcs_PTE = wiredInThingEnv,
636 pcs_insts = emptyInstEnv,
637 pcs_rules = emptyRuleBase,
642 initPersistentRenamerState :: IO PersistentRenamerState
643 = do us <- mkSplitUniqSupply 'r'
645 PRS { prsOrig = NameSupply { nsUniqs = us,
646 nsNames = initOrigNames,
648 prsDecls = (emptyNameEnv, 0),
649 prsInsts = (emptyBag, 0),
650 prsRules = (emptyBag, 0),
655 initOrigNames :: FiniteMap (ModuleName,OccName) Name
657 = grab knownKeyNames `plusFM` grab (map getName wiredInThings)
659 grab names = foldl add emptyFM names
661 = addToFM env (moduleName (nameModule name), nameOccName name) name