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 Rename ( renameStmt )
21 import RdrHsSyn ( RdrNameStmt )
23 import Id ( Id, idName, setGlobalIdDetails )
24 import IdInfo ( GlobalIdDetails(VanillaGlobal) )
25 import HscTypes ( InteractiveContext(..) )
26 import PrelNames ( iNTERACTIVE )
27 import StringBuffer ( stringToStringBuffer )
33 import IdInfo ( CafInfo(..), CgInfoEnv, CgInfo(..) )
34 import StringBuffer ( hGetStringBuffer, freeStringBuffer )
36 import Lex ( PState(..), ParseResult(..) )
37 import SrcLoc ( mkSrcLoc )
38 import Finder ( findModule )
39 import Rename ( checkOldIface, renameModule, closeIfaceDecls )
40 import Rules ( emptyRuleBase )
41 import PrelInfo ( wiredInThingEnv, wiredInThings )
42 import PrelNames ( vanillaSyntaxMap, knownKeyNames )
43 import MkIface ( mkFinalIface )
45 import InstEnv ( emptyInstEnv )
48 import CoreUtils ( coreBindsSize )
49 import CoreTidy ( tidyCorePgm )
50 import CorePrep ( corePrepPgm )
52 import CoreToStg ( coreToStg )
53 import SimplStg ( stg2stg )
54 import CodeGen ( codeGen )
55 import CodeOutput ( codeOutput )
57 import Module ( ModuleName, moduleName, mkHomeModule,
60 import ErrUtils ( dumpIfSet_dyn, showPass, printError )
61 import Util ( unJust )
62 import UniqSupply ( mkSplitUniqSupply )
64 import Bag ( emptyBag )
67 import CmStaticInfo ( GhciMode(..) )
68 import HscStats ( ppSourceStats )
70 import FiniteMap ( FiniteMap, plusFM, emptyFM, addToFM )
71 import OccName ( OccName )
72 import Name ( Name, nameModule, nameOccName, getName, isGlobalName )
73 import NameEnv ( emptyNameEnv, mkNameEnv )
74 import Module ( Module )
76 import IOExts ( newIORef, readIORef, writeIORef, unsafePerformIO )
79 import Maybe ( isJust, fromJust )
84 %************************************************************************
86 \subsection{The main compiler pipeline}
88 %************************************************************************
93 = HscFail PersistentCompilerState -- updated PCS
94 -- concluded that it wasn't necessary
95 | HscNoRecomp PersistentCompilerState -- updated PCS
96 ModDetails -- new details (HomeSymbolTable additions)
97 ModIface -- new iface (if any compilation was done)
99 | HscRecomp PersistentCompilerState -- updated PCS
100 ModDetails -- new details (HomeSymbolTable additions)
101 ModIface -- new iface (if any compilation was done)
102 Bool -- stub_h exists
103 Bool -- stub_c exists
104 (Maybe ([UnlinkedBCO],ItblEnv)) -- interpreted code, if any
107 -- no errors or warnings; the individual passes
108 -- (parse/rename/typecheck) print messages themselves
114 -> ModuleLocation -- location info
115 -> Bool -- True <=> source unchanged
116 -> Bool -- True <=> have an object file (for msgs only)
117 -> Maybe ModIface -- old interface, if available
118 -> HomeSymbolTable -- for home module ModDetails
120 -> PersistentCompilerState -- IN: persistent compiler state
123 hscMain ghci_mode dflags mod location source_unchanged have_object
124 maybe_old_iface hst hit pcs
126 showPass dflags ("Checking old interface for hs = "
127 ++ show (ml_hs_file location)
128 ++ ", hspp = " ++ show (ml_hspp_file location));
130 (pcs_ch, errs_found, (recomp_reqd, maybe_checked_iface))
131 <- _scc_ "checkOldIface"
132 checkOldIface ghci_mode dflags hit hst pcs (ml_hi_file location)
133 source_unchanged maybe_old_iface;
136 return (HscFail pcs_ch)
139 let no_old_iface = not (isJust maybe_checked_iface)
140 what_next | recomp_reqd || no_old_iface = hscRecomp
141 | otherwise = hscNoRecomp
143 what_next ghci_mode dflags have_object mod location
144 maybe_checked_iface hst hit pcs_ch
148 -- we definitely expect to have the old interface available
149 hscNoRecomp ghci_mode dflags have_object
150 mod location (Just old_iface) hst hit pcs_ch
151 | ghci_mode == OneShot
153 hPutStrLn stderr "compilation IS NOT required";
154 let { bomb = panic "hscNoRecomp:OneShot" };
155 return (HscNoRecomp pcs_ch bomb bomb)
159 when (verbosity dflags >= 1) $
160 hPutStrLn stderr ("Skipping " ++
161 compMsg have_object mod location);
164 (pcs_cl, closure_errs, cl_hs_decls)
165 <- closeIfaceDecls dflags hit hst pcs_ch old_iface ;
167 return (HscFail pcs_cl)
172 <- typecheckIface dflags pcs_cl hst old_iface (vanillaSyntaxMap, cl_hs_decls);
174 case maybe_tc_result of {
175 Nothing -> return (HscFail pcs_cl);
176 Just (pcs_tc, new_details) ->
178 return (HscNoRecomp pcs_tc new_details old_iface)
181 compMsg use_object mod location =
182 mod_str ++ take (max 0 (16 - length mod_str)) (repeat ' ')
183 ++" ( " ++ unJust "hscRecomp" (ml_hs_file location) ++ ", "
185 then unJust "hscRecomp" (ml_obj_file location)
188 where mod_str = moduleUserString mod
191 hscRecomp ghci_mode dflags have_object
192 mod location maybe_checked_iface hst hit pcs_ch
194 -- what target are we shooting for?
195 ; let toInterp = dopt_HscLang dflags == HscInterpreted
197 ; when (verbosity dflags >= 1) $
198 hPutStrLn stderr ("Compiling " ++
199 compMsg (not toInterp) mod location);
204 ; maybe_parsed <- myParseModule dflags
205 (unJust "hscRecomp:hspp" (ml_hspp_file location))
206 ; case maybe_parsed of {
207 Nothing -> return (HscFail pcs_ch);
208 Just rdr_module -> do {
209 ; let this_mod = mkHomeModule (hsModuleName rdr_module)
214 ; (pcs_rn, print_unqualified, maybe_rn_result)
216 renameModule dflags hit hst pcs_ch this_mod rdr_module
217 ; case maybe_rn_result of {
218 Nothing -> return (HscFail pcs_ch{-was: pcs_rn-});
219 Just (is_exported, new_iface, rn_hs_decls) -> do {
221 -- In interactive mode, we don't want to discard any top-level entities at
222 -- all (eg. do not inline them away during simplification), and retain them
223 -- all in the TypeEnv so they are available from the command line.
225 -- isGlobalName separates the user-defined top-level names from those
226 -- introduced by the type checker.
227 ; let dont_discard | ghci_mode == Interactive = isGlobalName
228 | otherwise = is_exported
234 <- _scc_ "TypeCheck" typecheckModule dflags pcs_rn hst new_iface
235 print_unqualified rn_hs_decls
236 ; case maybe_tc_result of {
237 Nothing -> return (HscFail pcs_ch{-was: pcs_rn-});
238 Just (pcs_tc, tc_result) -> do {
243 ; (ds_details, foreign_stuff)
245 deSugar dflags pcs_tc hst this_mod print_unqualified tc_result
248 <- if ghci_mode == OneShot
249 then do init_pcs <- initPersistentCompilerState
250 init_prs <- initPersistentRenamerState
252 rules = pcs_rules pcs_tc
253 orig_tc = prsOrig (pcs_PRS pcs_tc)
254 new_prs = init_prs{ prsOrig=orig_tc }
256 orig_tc `seq` rules `seq` new_prs `seq`
257 return init_pcs{ pcs_PRS = new_prs,
266 core2core dflags pcs_middle hst dont_discard ds_details
271 ; cg_info_ref <- newIORef Nothing ;
272 ; let cg_info :: CgInfoEnv
273 cg_info = unsafePerformIO $ do {
274 maybe_cg_env <- readIORef cg_info_ref ;
276 Just env -> return env
277 Nothing -> do { printError "Urk! Looked at CgInfo too early!";
278 return emptyNameEnv } }
279 -- cg_info_ref will be filled in just after restOfCodeGeneration
280 -- Meanwhile, tidyCorePgm is careful not to look at cg_info!
282 ; (pcs_simpl, tidy_details)
284 tidyCorePgm dflags this_mod pcs_middle cg_info simpl_details
286 ; pcs_final <- if ghci_mode == OneShot then initPersistentCompilerState
287 else return pcs_simpl
289 -- alive at this point:
294 -- PREPARE FOR CODE GENERATION
296 -- Do saturation and convert to A-normal form
297 ; prepd_details <- _scc_ "CorePrep" corePrepPgm dflags tidy_details
300 -- CONVERT TO STG and COMPLETE CODE GENERATION
303 ModDetails{md_binds=binds, md_types=env_tc} = prepd_details
305 local_tycons = typeEnvTyCons env_tc
306 local_classes = typeEnvClasses env_tc
308 imported_module_names = map ideclName (hsModuleImports rdr_module)
310 mod_name_to_Module nm
311 = do m <- findModule nm ; return (fst (fromJust m))
313 (h_code,c_code,fe_binders) = foreign_stuff
315 ; imported_modules <- mapM mod_name_to_Module imported_module_names
317 ; (stub_h_exists, stub_c_exists, maybe_bcos, final_iface )
320 ----------------- Generate byte code ------------------
321 (bcos,itbl_env) <- byteCodeGen dflags binds
322 local_tycons local_classes
324 -- Fill in the code-gen info
325 writeIORef cg_info_ref (Just emptyNameEnv)
327 ------------------ BUILD THE NEW ModIface ------------
328 final_iface <- _scc_ "MkFinalIface"
329 mkFinalIface ghci_mode dflags location
330 maybe_checked_iface new_iface tidy_details
332 return ( False, False, Just (bcos,itbl_env), final_iface )
335 ----------------- Convert to STG ------------------
336 (stg_binds, cost_centre_info, stg_back_end_info)
338 myCoreToStg dflags this_mod binds
340 -- Fill in the code-gen info for the earlier tidyCorePgm
341 writeIORef cg_info_ref (Just stg_back_end_info)
343 ------------------ BUILD THE NEW ModIface ------------
344 final_iface <- _scc_ "MkFinalIface"
345 mkFinalIface ghci_mode dflags location
346 maybe_checked_iface new_iface tidy_details
348 ------------------ Code generation ------------------
349 abstractC <- _scc_ "CodeGen"
350 codeGen dflags this_mod imported_modules
351 cost_centre_info fe_binders
352 local_tycons stg_binds
354 ------------------ Code output -----------------------
355 (stub_h_exists, stub_c_exists)
356 <- codeOutput dflags this_mod local_tycons
358 c_code h_code abstractC
360 return (stub_h_exists, stub_c_exists, Nothing, final_iface)
362 ; let final_details = tidy_details {md_binds = []}
365 -- and the answer is ...
366 ; return (HscRecomp pcs_final
369 stub_h_exists stub_c_exists
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
531 -- Prepare for codegen
532 ; prepd_expr <- corePrepExpr dflags tidy_expr
535 ; bcos <- coreExprToBCOs dflags prepd_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