2 % (c) The GRASP/AQUA Project, Glasgow University, 1993-2000
4 \section[GHC_Main]{Main driver for Glasgow Haskell compiler}
7 module HscMain ( HscResult(..), hscMain,
11 initPersistentCompilerState ) where
13 #include "HsVersions.h"
16 import RdrHsSyn ( RdrNameStmt )
17 import Rename ( renameStmt )
18 import ByteCodeGen ( byteCodeGen )
19 import Id ( Id, idName, setGlobalIdDetails )
20 import IdInfo ( GlobalIdDetails(VanillaGlobal) )
21 import HscTypes ( InteractiveContext(..), TyThing(..) )
22 import PrelNames ( iINTERACTIVE )
23 import CoreTidy ( tidyCoreExpr )
24 import StringBuffer ( stringToStringBuffer )
30 import IdInfo ( CafInfo(..), CgInfoEnv, CgInfo(..) )
31 import StringBuffer ( hGetStringBuffer, freeStringBuffer )
33 import Lex ( PState(..), ParseResult(..) )
34 import SrcLoc ( mkSrcLoc )
35 import Rename ( checkOldIface, renameModule, closeIfaceDecls )
36 import Rules ( emptyRuleBase )
37 import PrelInfo ( wiredInThingEnv, wiredInThings )
38 import PrelNames ( vanillaSyntaxMap, knownKeyNames )
39 import MkIface ( completeIface, writeIface, pprIface )
41 import InstEnv ( emptyInstEnv )
44 import CoreUtils ( coreBindsSize )
45 import CoreTidy ( tidyCorePgm )
46 import CorePrep ( corePrepPgm )
48 import CoreToStg ( coreToStg )
49 import SimplStg ( stg2stg )
50 import CodeGen ( codeGen )
51 import CodeOutput ( codeOutput )
53 import Module ( ModuleName, moduleName, mkHomeModule,
56 import ErrUtils ( dumpIfSet_dyn, showPass, printError )
57 import Util ( unJust )
58 import UniqSupply ( mkSplitUniqSupply )
60 import Bag ( emptyBag )
63 import CmStaticInfo ( GhciMode(..) )
64 import HscStats ( ppSourceStats )
66 import FiniteMap ( FiniteMap, plusFM, emptyFM, addToFM )
67 import OccName ( OccName )
68 import Name ( Name, nameModule, nameOccName, getName, isGlobalName )
69 import NameEnv ( emptyNameEnv, mkNameEnv )
70 import Module ( Module, lookupModuleEnvByName )
71 import Maybes ( orElse )
73 import IOExts ( newIORef, readIORef, writeIORef, unsafePerformIO )
76 import Maybe ( isJust )
81 %************************************************************************
83 \subsection{The main compiler pipeline}
85 %************************************************************************
90 = HscFail PersistentCompilerState -- updated PCS
91 -- concluded that it wasn't necessary
92 | HscNoRecomp PersistentCompilerState -- updated PCS
93 ModDetails -- new details (HomeSymbolTable additions)
94 ModIface -- new iface (if any compilation was done)
96 | HscRecomp PersistentCompilerState -- updated PCS
97 ModDetails -- new details (HomeSymbolTable additions)
98 ModIface -- new iface (if any compilation was done)
99 (Maybe String) -- generated stub_h filename (in TMPDIR)
100 (Maybe String) -- generated stub_c filename (in TMPDIR)
101 (Maybe ([UnlinkedBCO],ItblEnv)) -- interpreted code, if any
104 -- no errors or warnings; the individual passes
105 -- (parse/rename/typecheck) print messages themselves
111 -> ModuleLocation -- location info
112 -> Bool -- source unchanged?
113 -> Maybe ModIface -- old interface, if available
114 -> HomeSymbolTable -- for home module ModDetails
116 -> PersistentCompilerState -- IN: persistent compiler state
119 hscMain ghci_mode dflags mod location source_unchanged maybe_old_iface hst hit pcs
121 showPass dflags ("Checking old interface for hs = "
122 ++ show (ml_hs_file location)
123 ++ ", hspp = " ++ show (ml_hspp_file location));
125 (pcs_ch, errs_found, (recomp_reqd, maybe_checked_iface))
126 <- checkOldIface ghci_mode dflags hit hst pcs
127 (unJust "hscMain" (ml_hi_file location))
128 source_unchanged maybe_old_iface;
131 return (HscFail pcs_ch)
134 let no_old_iface = not (isJust maybe_checked_iface)
135 what_next | recomp_reqd || no_old_iface = hscRecomp
136 | otherwise = hscNoRecomp
138 what_next ghci_mode dflags mod location maybe_checked_iface
143 -- we definitely expect to have the old interface available
144 hscNoRecomp ghci_mode dflags mod location (Just old_iface) hst hit pcs_ch
145 | ghci_mode == OneShot
147 hPutStrLn stderr "compilation IS NOT required";
148 let { bomb = panic "hscNoRecomp:OneShot" };
149 return (HscNoRecomp pcs_ch bomb bomb)
153 when (verbosity dflags >= 1) $
154 hPutStrLn stderr ("Skipping " ++ compMsg mod location);
157 (pcs_cl, closure_errs, cl_hs_decls)
158 <- closeIfaceDecls dflags hit hst pcs_ch old_iface ;
160 return (HscFail pcs_cl)
165 <- typecheckIface dflags pcs_cl hst old_iface (vanillaSyntaxMap, cl_hs_decls);
167 case maybe_tc_result of {
168 Nothing -> return (HscFail pcs_cl);
169 Just (pcs_tc, new_details) ->
171 return (HscNoRecomp pcs_tc new_details old_iface)
174 compMsg mod location =
175 mod_str ++ take (12 - length mod_str) (repeat ' ')
176 ++ " (" ++ unJust "hscRecomp" (ml_hs_file location) ++ ")"
177 where mod_str = moduleUserString mod
180 hscRecomp ghci_mode dflags mod location maybe_checked_iface hst hit pcs_ch
182 ; when (verbosity dflags >= 1) $
183 hPutStrLn stderr ("Compiling " ++ compMsg mod location);
185 -- what target are we shooting for?
186 ; let toInterp = dopt_HscLang dflags == HscInterpreted
191 ; maybe_parsed <- myParseModule dflags
192 (unJust "hscRecomp:hspp" (ml_hspp_file location))
193 ; case maybe_parsed of {
194 Nothing -> return (HscFail pcs_ch);
195 Just rdr_module -> do {
196 ; let this_mod = mkHomeModule (hsModuleName rdr_module)
201 ; (pcs_rn, print_unqualified, maybe_rn_result)
203 renameModule dflags hit hst pcs_ch this_mod rdr_module
204 ; case maybe_rn_result of {
205 Nothing -> return (HscFail pcs_ch{-was: pcs_rn-});
206 Just (is_exported, new_iface, rn_hs_decls) -> do {
208 -- In interactive mode, we don't want to discard any top-level entities at
209 -- all (eg. do not inline them away during simplification), and retain them
210 -- all in the TypeEnv so they are available from the command line.
212 -- isGlobalName separates the user-defined top-level names from those
213 -- introduced by the type checker.
214 ; let dont_discard | ghci_mode == Interactive = isGlobalName
215 | otherwise = is_exported
221 <- _scc_ "TypeCheck" typecheckModule dflags pcs_rn hst new_iface
222 print_unqualified rn_hs_decls
223 ; case maybe_tc_result of {
224 Nothing -> return (HscFail pcs_ch{-was: pcs_rn-});
225 Just (pcs_tc, tc_result) -> do {
230 ; (ds_details, foreign_stuff)
232 deSugar dflags pcs_tc hst this_mod print_unqualified tc_result
239 core2core dflags pcs_tc hst dont_discard ds_details
244 ; cg_info_ref <- newIORef Nothing ;
245 ; let cg_info :: CgInfoEnv
246 cg_info = unsafePerformIO $ do {
247 maybe_cg_env <- readIORef cg_info_ref ;
249 Just env -> return env
250 Nothing -> do { printError "Urk! Looked at CgInfo too early!";
251 return emptyNameEnv } }
252 -- cg_info_ref will be filled in just after restOfCodeGeneration
253 -- Meanwhile, tidyCorePgm is careful not to look at cg_info!
255 ; (pcs_simpl, tidy_details)
256 <- tidyCorePgm dflags this_mod pcs_tc cg_info simpl_details
259 -- PREPARE FOR CODE GENERATION
261 -- Do saturation and convert to A-normal form
262 ; prepd_details <- corePrepPgm dflags tidy_details
265 -- CONVERT TO STG and COMPLETE CODE GENERATION
268 ModDetails{md_binds=binds, md_types=env_tc} = prepd_details
270 local_tycons = typeEnvTyCons env_tc
271 local_classes = typeEnvClasses env_tc
273 imported_module_names = map ideclName (hsModuleImports rdr_module)
274 imported_modules = map mod_name_to_Module imported_module_names
276 (h_code,c_code,fe_binders) = foreign_stuff
278 pit = pcs_PIT pcs_simpl
280 mod_name_to_Module :: ModuleName -> Module
281 mod_name_to_Module nm
282 = let str_mi = lookupModuleEnvByName hit nm `orElse`
283 lookupModuleEnvByName pit nm `orElse`
284 pprPanic "mod_name_to_Module: no hst or pst mapping for"
288 ; (maybe_stub_h_filename, maybe_stub_c_filename,
289 maybe_bcos, final_iface )
292 ----------------- Generate byte code ------------------
293 (bcos,itbl_env) <- byteCodeGen dflags binds
294 local_tycons local_classes
296 -- Fill in the code-gen info
297 writeIORef cg_info_ref (Just emptyNameEnv)
299 ------------------ BUILD THE NEW ModIface ------------
300 final_iface <- _scc_ "MkFinalIface"
301 mkFinalIface ghci_mode dflags location
302 maybe_checked_iface new_iface tidy_details
304 return ( Nothing, Nothing,
305 Just (bcos,itbl_env), final_iface )
308 ----------------- Convert to STG ------------------
309 (stg_binds, cost_centre_info, stg_back_end_info)
311 myCoreToStg dflags this_mod binds
313 -- Fill in the code-gen info for the earlier tidyCorePgm
314 writeIORef cg_info_ref (Just stg_back_end_info)
316 ------------------ BUILD THE NEW ModIface ------------
317 final_iface <- _scc_ "MkFinalIface"
318 mkFinalIface ghci_mode dflags location
319 maybe_checked_iface new_iface tidy_details
321 ------------------ Code generation ------------------
322 abstractC <- _scc_ "CodeGen"
323 codeGen dflags this_mod imported_modules
324 cost_centre_info fe_binders
325 local_tycons stg_binds
327 ------------------ Code output -----------------------
328 (maybe_stub_h_name, maybe_stub_c_name)
329 <- codeOutput dflags this_mod local_tycons
331 c_code h_code abstractC
333 return ( maybe_stub_h_name, maybe_stub_c_name,
334 Nothing, final_iface )
336 ; let final_details = tidy_details {md_binds = []}
339 -- and the answer is ...
340 ; return (HscRecomp pcs_simpl
343 maybe_stub_h_filename maybe_stub_c_filename
349 mkFinalIface ghci_mode dflags location
350 maybe_old_iface new_iface new_details
351 = case completeIface maybe_old_iface new_iface new_details of
353 (new_iface, Nothing) -- no change in the interfacfe
354 -> do when (dopt Opt_D_dump_hi_diffs dflags)
355 (printDump (text "INTERFACE UNCHANGED"))
356 dumpIfSet_dyn dflags Opt_D_dump_hi
357 "UNCHANGED FINAL INTERFACE" (pprIface new_iface)
360 (new_iface, Just sdoc_diffs)
361 -> do dumpIfSet_dyn dflags Opt_D_dump_hi_diffs "INTERFACE HAS CHANGED"
363 dumpIfSet_dyn dflags Opt_D_dump_hi "NEW FINAL INTERFACE"
366 -- Write the interface file, if not in interactive mode
367 when (ghci_mode /= Interactive)
368 (writeIface (unJust "hscRecomp:hi" (ml_hi_file location))
373 myParseModule dflags src_filename
374 = do -------------------------- Parser ----------------
375 showPass dflags "Parser"
378 buf <- hGetStringBuffer True{-expand tabs-} src_filename
380 let glaexts | dopt Opt_GlasgowExts dflags = 1#
383 case parseModule buf PState{ bol = 0#, atbol = 1#,
384 context = [], glasgow_exts = glaexts,
385 loc = mkSrcLoc (_PK_ src_filename) 1 } of {
387 PFailed err -> do { hPutStrLn stderr (showSDoc err);
388 freeStringBuffer buf;
391 POk _ rdr_module@(HsModule mod_name _ _ _ _ _ _) -> do {
393 dumpIfSet_dyn dflags Opt_D_dump_parsed "Parser" (ppr rdr_module) ;
395 dumpIfSet_dyn dflags Opt_D_source_stats "Source Statistics"
396 (ppSourceStats False rdr_module) ;
398 return (Just rdr_module)
399 -- ToDo: free the string buffer later.
403 myCoreToStg dflags this_mod tidy_binds
405 () <- coreBindsSize tidy_binds `seq` return ()
406 -- TEMP: the above call zaps some space usage allocated by the
407 -- simplifier, which for reasons I don't understand, persists
408 -- thoroughout code generation
410 stg_binds <- _scc_ "Core2Stg" coreToStg dflags tidy_binds
412 (stg_binds2, cost_centre_info)
413 <- _scc_ "Core2Stg" stg2stg dflags this_mod stg_binds
415 let env_rhs :: CgInfoEnv
416 env_rhs = mkNameEnv [ (idName bndr, CgInfo (stgRhsArity rhs) caf_info)
417 | (bind,_) <- stg_binds2,
419 | stgBindHasCafRefs bind = MayHaveCafRefs
420 | otherwise = NoCafRefs,
421 (bndr,rhs) <- stgBindPairs bind ]
423 return (stg_binds2, cost_centre_info, env_rhs)
425 stgBindPairs (StgNonRec _ b r) = [(b,r)]
426 stgBindPairs (StgRec _ prs) = prs
430 %************************************************************************
432 \subsection{Compiling a do-statement}
434 %************************************************************************
442 -> PersistentCompilerState -- IN: persistent compiler state
443 -> InteractiveContext -- Context for compiling
444 -> String -- The statement
445 -> Bool -- just treat it as an expression
446 -> IO ( PersistentCompilerState,
452 When the UnlinkedBCOExpr is linked you get an HValue of type
454 When you run it you get a list of HValues that should be
455 the same length as the list of names; add them to the ClosureEnv.
457 A naked expression returns a singleton Name [it].
459 What you type The IO [HValue] that hscStmt returns
460 ------------- ------------------------------------
461 let pat = expr ==> let pat = expr in return [coerce HVal x, coerce HVal y, ...]
464 pat <- expr ==> expr >>= \ pat -> return [coerce HVal x, coerce HVal y, ...]
467 expr (of IO type) ==> expr >>= \ v -> return [v]
468 [NB: result not printed] bindings: [it]
471 expr (of non-IO type,
472 result showable) ==> let v = expr in print v >> return [v]
475 expr (of non-IO type,
476 result not showable) ==> error
479 hscStmt dflags hst hit pcs0 icontext stmt just_expr
483 ic_type_env = type_env,
484 ic_module = scope_mod } = icontext
486 do { maybe_stmt <- hscParseStmt dflags stmt
488 Nothing -> return (pcs0, Nothing)
489 Just parsed_stmt -> do {
491 let { notExprStmt (ExprStmt _ _) = False;
495 if (just_expr && notExprStmt parsed_stmt)
496 then do hPutStrLn stderr ("not an expression: `" ++ stmt ++ "'")
497 return (pcs0, Nothing)
501 (pcs1, print_unqual, maybe_renamed_stmt)
502 <- renameStmt dflags hit hst pcs0 scope_mod
503 iNTERACTIVE rn_env parsed_stmt
505 ; case maybe_renamed_stmt of
506 Nothing -> return (pcs0, Nothing)
507 Just (bound_names, rn_stmt) -> do {
512 then case rn_stmt of { (syn, ExprStmt e _, decls) ->
513 typecheckExpr dflags pcs1 hst type_env
514 print_unqual iNTERACTIVE (syn,e,decls) }
515 else typecheckStmt dflags pcs1 hst type_env
516 print_unqual iNTERACTIVE bound_names rn_stmt
518 ; case maybe_tc_return of
519 Nothing -> return (pcs0, Nothing)
520 Just (pcs2, tc_expr, bound_ids, ty) -> do {
523 ds_expr <- deSugarExpr dflags pcs2 hst iNTERACTIVE print_unqual tc_expr
526 ; simpl_expr <- simplifyExpr dflags pcs2 hst ds_expr
528 -- Tidy it (temporary, until coreSat does cloning)
529 ; tidy_expr <- tidyCoreExpr simpl_expr
532 ; sat_expr <- coreSatExpr dflags tidy_expr
535 ; bcos <- coreExprToBCOs dflags sat_expr
538 -- Make all the bound ids "global" ids, now that
539 -- they're notionally top-level bindings. This is
540 -- important: otherwise when we come to compile an expression
541 -- using these ids later, the byte code generator will consider
542 -- the occurrences to be free rather than global.
543 global_bound_ids = map globaliseId bound_ids;
544 globaliseId id = setGlobalIdDetails id VanillaGlobal
546 ; return (pcs2, Just (global_bound_ids, ty, bcos))
550 hscParseStmt :: DynFlags -> String -> IO (Maybe RdrNameStmt)
551 hscParseStmt dflags str
552 = do -------------------------- Parser ----------------
553 showPass dflags "Parser"
556 buf <- stringToStringBuffer str
558 let glaexts | dopt Opt_GlasgowExts dflags = 1#
561 case parseStmt buf PState{ bol = 0#, atbol = 1#,
562 context = [], glasgow_exts = glaexts,
563 loc = mkSrcLoc SLIT("<no file>") 0 } of {
565 PFailed err -> do { hPutStrLn stderr (showSDoc err);
566 -- Not yet implemented in <4.11 freeStringBuffer buf;
569 -- no stmt: the line consisted of just space or comments
570 POk _ Nothing -> return Nothing;
572 POk _ (Just rdr_stmt) -> do {
574 --ToDo: can't free the string buffer until we've finished this
575 -- compilation sweep and all the identifiers have gone away.
576 --freeStringBuffer buf;
577 dumpIfSet_dyn dflags Opt_D_dump_parsed "Parser" (ppr rdr_stmt);
578 return (Just rdr_stmt)
583 %************************************************************************
585 \subsection{Initial persistent state}
587 %************************************************************************
590 initPersistentCompilerState :: IO PersistentCompilerState
591 initPersistentCompilerState
592 = do prs <- initPersistentRenamerState
594 PCS { pcs_PIT = emptyIfaceTable,
595 pcs_PTE = wiredInThingEnv,
596 pcs_insts = emptyInstEnv,
597 pcs_rules = emptyRuleBase,
602 initPersistentRenamerState :: IO PersistentRenamerState
603 = do us <- mkSplitUniqSupply 'r'
605 PRS { prsOrig = NameSupply { nsUniqs = us,
606 nsNames = initOrigNames,
608 prsDecls = (emptyNameEnv, 0),
609 prsInsts = (emptyBag, 0),
610 prsRules = (emptyBag, 0),
615 initOrigNames :: FiniteMap (ModuleName,OccName) Name
617 = grab knownKeyNames `plusFM` grab (map getName wiredInThings)
619 grab names = foldl add emptyFM names
621 = addToFM env (moduleName (nameModule name), nameOccName name) name
624 initRules :: PackageRuleBase
625 initRules = emptyRuleBase
627 foldl add emptyVarEnv builtinRules
630 = extendRuleBase env name rule