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
133 (unJust "hscMain" (ml_hi_file location))
134 source_unchanged maybe_old_iface;
137 return (HscFail pcs_ch)
140 let no_old_iface = not (isJust maybe_checked_iface)
141 what_next | recomp_reqd || no_old_iface = hscRecomp
142 | otherwise = hscNoRecomp
144 what_next ghci_mode dflags have_object mod location
145 maybe_checked_iface hst hit pcs_ch
149 -- we definitely expect to have the old interface available
150 hscNoRecomp ghci_mode dflags have_object
151 mod location (Just old_iface) hst hit pcs_ch
152 | ghci_mode == OneShot
154 hPutStrLn stderr "compilation IS NOT required";
155 let { bomb = panic "hscNoRecomp:OneShot" };
156 return (HscNoRecomp pcs_ch bomb bomb)
160 when (verbosity dflags >= 1) $
161 hPutStrLn stderr ("Skipping " ++
162 compMsg have_object mod location);
165 (pcs_cl, closure_errs, cl_hs_decls)
166 <- closeIfaceDecls dflags hit hst pcs_ch old_iface ;
168 return (HscFail pcs_cl)
173 <- typecheckIface dflags pcs_cl hst old_iface (vanillaSyntaxMap, cl_hs_decls);
175 case maybe_tc_result of {
176 Nothing -> return (HscFail pcs_cl);
177 Just (pcs_tc, new_details) ->
179 return (HscNoRecomp pcs_tc new_details old_iface)
182 compMsg use_object mod location =
183 mod_str ++ take (max 0 (16 - length mod_str)) (repeat ' ')
184 ++" ( " ++ unJust "hscRecomp" (ml_hs_file location) ++ ", "
186 then unJust "hscRecomp" (ml_obj_file location)
189 where mod_str = moduleUserString mod
192 hscRecomp ghci_mode dflags have_object
193 mod location maybe_checked_iface hst hit pcs_ch
195 -- what target are we shooting for?
196 ; let toInterp = dopt_HscLang dflags == HscInterpreted
198 ; when (verbosity dflags >= 1) $
199 hPutStrLn stderr ("Compiling " ++
200 compMsg (not toInterp) mod location);
205 ; maybe_parsed <- myParseModule dflags
206 (unJust "hscRecomp:hspp" (ml_hspp_file location))
207 ; case maybe_parsed of {
208 Nothing -> return (HscFail pcs_ch);
209 Just rdr_module -> do {
210 ; let this_mod = mkHomeModule (hsModuleName rdr_module)
215 ; (pcs_rn, print_unqualified, maybe_rn_result)
217 renameModule dflags hit hst pcs_ch this_mod rdr_module
218 ; case maybe_rn_result of {
219 Nothing -> return (HscFail pcs_ch{-was: pcs_rn-});
220 Just (is_exported, new_iface, rn_hs_decls) -> do {
222 -- In interactive mode, we don't want to discard any top-level entities at
223 -- all (eg. do not inline them away during simplification), and retain them
224 -- all in the TypeEnv so they are available from the command line.
226 -- isGlobalName separates the user-defined top-level names from those
227 -- introduced by the type checker.
228 ; let dont_discard | ghci_mode == Interactive = isGlobalName
229 | otherwise = is_exported
235 <- _scc_ "TypeCheck" typecheckModule dflags pcs_rn hst new_iface
236 print_unqualified rn_hs_decls
237 ; case maybe_tc_result of {
238 Nothing -> return (HscFail pcs_ch{-was: pcs_rn-});
239 Just (pcs_tc, tc_result) -> do {
244 ; (ds_details, foreign_stuff)
246 deSugar dflags pcs_tc hst this_mod print_unqualified tc_result
249 <- if ghci_mode == OneShot
250 then do init_pcs <- initPersistentCompilerState
251 init_prs <- initPersistentRenamerState
253 rules = pcs_rules pcs_tc
254 orig_tc = prsOrig (pcs_PRS pcs_tc)
255 new_prs = init_prs{ prsOrig=orig_tc }
257 orig_tc `seq` rules `seq` new_prs `seq`
258 return init_pcs{ pcs_PRS = new_prs,
267 core2core dflags pcs_middle hst dont_discard ds_details
272 ; cg_info_ref <- newIORef Nothing ;
273 ; let cg_info :: CgInfoEnv
274 cg_info = unsafePerformIO $ do {
275 maybe_cg_env <- readIORef cg_info_ref ;
277 Just env -> return env
278 Nothing -> do { printError "Urk! Looked at CgInfo too early!";
279 return emptyNameEnv } }
280 -- cg_info_ref will be filled in just after restOfCodeGeneration
281 -- Meanwhile, tidyCorePgm is careful not to look at cg_info!
283 ; (pcs_simpl, tidy_details)
285 tidyCorePgm dflags this_mod pcs_middle cg_info simpl_details
287 ; pcs_final <- if ghci_mode == OneShot then initPersistentCompilerState
288 else return pcs_simpl
290 -- alive at this point:
295 -- PREPARE FOR CODE GENERATION
297 -- Do saturation and convert to A-normal form
298 ; prepd_details <- _scc_ "CorePrep" corePrepPgm dflags tidy_details
301 -- CONVERT TO STG and COMPLETE CODE GENERATION
304 ModDetails{md_binds=binds, md_types=env_tc} = prepd_details
306 local_tycons = typeEnvTyCons env_tc
307 local_classes = typeEnvClasses env_tc
309 imported_module_names = map ideclName (hsModuleImports rdr_module)
311 mod_name_to_Module nm
312 = do m <- findModule nm ; return (fst (fromJust m))
314 (h_code,c_code,fe_binders) = foreign_stuff
316 ; imported_modules <- mapM mod_name_to_Module imported_module_names
318 ; (stub_h_exists, stub_c_exists, maybe_bcos, final_iface )
321 ----------------- Generate byte code ------------------
322 (bcos,itbl_env) <- byteCodeGen dflags binds
323 local_tycons local_classes
325 -- Fill in the code-gen info
326 writeIORef cg_info_ref (Just emptyNameEnv)
328 ------------------ BUILD THE NEW ModIface ------------
329 final_iface <- _scc_ "MkFinalIface"
330 mkFinalIface ghci_mode dflags location
331 maybe_checked_iface new_iface tidy_details
333 return ( False, False, Just (bcos,itbl_env), final_iface )
336 ----------------- Convert to STG ------------------
337 (stg_binds, cost_centre_info, stg_back_end_info)
339 myCoreToStg dflags this_mod binds
341 -- Fill in the code-gen info for the earlier tidyCorePgm
342 writeIORef cg_info_ref (Just stg_back_end_info)
344 ------------------ BUILD THE NEW ModIface ------------
345 final_iface <- _scc_ "MkFinalIface"
346 mkFinalIface ghci_mode dflags location
347 maybe_checked_iface new_iface tidy_details
349 ------------------ Code generation ------------------
350 abstractC <- _scc_ "CodeGen"
351 codeGen dflags this_mod imported_modules
352 cost_centre_info fe_binders
353 local_tycons stg_binds
355 ------------------ Code output -----------------------
356 (stub_h_exists, stub_c_exists)
357 <- codeOutput dflags this_mod local_tycons
359 c_code h_code abstractC
361 return (stub_h_exists, stub_c_exists, Nothing, final_iface)
363 ; let final_details = tidy_details {md_binds = []}
366 -- and the answer is ...
367 ; return (HscRecomp pcs_final
370 stub_h_exists stub_c_exists
374 myParseModule dflags src_filename
375 = do -------------------------- Parser ----------------
376 showPass dflags "Parser"
379 buf <- hGetStringBuffer True{-expand tabs-} src_filename
381 let glaexts | dopt Opt_GlasgowExts dflags = 1#
384 case parseModule buf PState{ bol = 0#, atbol = 1#,
385 context = [], glasgow_exts = glaexts,
386 loc = mkSrcLoc (_PK_ src_filename) 1 } of {
388 PFailed err -> do { hPutStrLn stderr (showSDoc err);
389 freeStringBuffer buf;
392 POk _ rdr_module@(HsModule mod_name _ _ _ _ _ _) -> do {
394 dumpIfSet_dyn dflags Opt_D_dump_parsed "Parser" (ppr rdr_module) ;
396 dumpIfSet_dyn dflags Opt_D_source_stats "Source Statistics"
397 (ppSourceStats False rdr_module) ;
399 return (Just rdr_module)
400 -- ToDo: free the string buffer later.
404 myCoreToStg dflags this_mod tidy_binds
406 () <- coreBindsSize tidy_binds `seq` return ()
407 -- TEMP: the above call zaps some space usage allocated by the
408 -- simplifier, which for reasons I don't understand, persists
409 -- thoroughout code generation
411 stg_binds <- _scc_ "Core2Stg" coreToStg dflags tidy_binds
413 (stg_binds2, cost_centre_info)
414 <- _scc_ "Core2Stg" stg2stg dflags this_mod stg_binds
416 let env_rhs :: CgInfoEnv
417 env_rhs = mkNameEnv [ (idName bndr, CgInfo (stgRhsArity rhs) caf_info)
418 | (bind,_) <- stg_binds2,
420 | stgBindHasCafRefs bind = MayHaveCafRefs
421 | otherwise = NoCafRefs,
422 (bndr,rhs) <- stgBindPairs bind ]
424 return (stg_binds2, cost_centre_info, env_rhs)
426 stgBindPairs (StgNonRec _ b r) = [(b,r)]
427 stgBindPairs (StgRec _ prs) = prs
431 %************************************************************************
433 \subsection{Compiling a do-statement}
435 %************************************************************************
443 -> PersistentCompilerState -- IN: persistent compiler state
444 -> InteractiveContext -- Context for compiling
445 -> String -- The statement
446 -> Bool -- just treat it as an expression
447 -> IO ( PersistentCompilerState,
453 When the UnlinkedBCOExpr is linked you get an HValue of type
455 When you run it you get a list of HValues that should be
456 the same length as the list of names; add them to the ClosureEnv.
458 A naked expression returns a singleton Name [it].
460 What you type The IO [HValue] that hscStmt returns
461 ------------- ------------------------------------
462 let pat = expr ==> let pat = expr in return [coerce HVal x, coerce HVal y, ...]
465 pat <- expr ==> expr >>= \ pat -> return [coerce HVal x, coerce HVal y, ...]
468 expr (of IO type) ==> expr >>= \ v -> return [v]
469 [NB: result not printed] bindings: [it]
472 expr (of non-IO type,
473 result showable) ==> let v = expr in print v >> return [v]
476 expr (of non-IO type,
477 result not showable) ==> error
480 hscStmt dflags hst hit pcs0 icontext stmt just_expr
484 ic_type_env = type_env,
485 ic_module = scope_mod } = icontext
487 do { maybe_stmt <- hscParseStmt dflags stmt
489 Nothing -> return (pcs0, Nothing)
490 Just parsed_stmt -> do {
492 let { notExprStmt (ExprStmt _ _) = False;
496 if (just_expr && notExprStmt parsed_stmt)
497 then do hPutStrLn stderr ("not an expression: `" ++ stmt ++ "'")
498 return (pcs0, Nothing)
502 (pcs1, print_unqual, maybe_renamed_stmt)
503 <- renameStmt dflags hit hst pcs0 scope_mod
504 iNTERACTIVE rn_env parsed_stmt
506 ; case maybe_renamed_stmt of
507 Nothing -> return (pcs0, Nothing)
508 Just (bound_names, rn_stmt) -> do {
513 then case rn_stmt of { (syn, ExprStmt e _, decls) ->
514 typecheckExpr dflags pcs1 hst type_env
515 print_unqual iNTERACTIVE (syn,e,decls) }
516 else typecheckStmt dflags pcs1 hst type_env
517 print_unqual iNTERACTIVE bound_names rn_stmt
519 ; case maybe_tc_return of
520 Nothing -> return (pcs0, Nothing)
521 Just (pcs2, tc_expr, bound_ids, ty) -> do {
524 ds_expr <- deSugarExpr dflags pcs2 hst iNTERACTIVE print_unqual tc_expr
527 ; simpl_expr <- simplifyExpr dflags pcs2 hst ds_expr
529 -- Tidy it (temporary, until coreSat does cloning)
530 ; tidy_expr <- tidyCoreExpr simpl_expr
532 -- Prepare for codegen
533 ; prepd_expr <- corePrepExpr dflags tidy_expr
536 ; bcos <- coreExprToBCOs dflags prepd_expr
539 -- Make all the bound ids "global" ids, now that
540 -- they're notionally top-level bindings. This is
541 -- important: otherwise when we come to compile an expression
542 -- using these ids later, the byte code generator will consider
543 -- the occurrences to be free rather than global.
544 global_bound_ids = map globaliseId bound_ids;
545 globaliseId id = setGlobalIdDetails id VanillaGlobal
547 ; return (pcs2, Just (global_bound_ids, ty, bcos))
551 hscParseStmt :: DynFlags -> String -> IO (Maybe RdrNameStmt)
552 hscParseStmt dflags str
553 = do -------------------------- Parser ----------------
554 showPass dflags "Parser"
557 buf <- stringToStringBuffer str
559 let glaexts | dopt Opt_GlasgowExts dflags = 1#
562 case parseStmt buf PState{ bol = 0#, atbol = 1#,
563 context = [], glasgow_exts = glaexts,
564 loc = mkSrcLoc SLIT("<no file>") 0 } of {
566 PFailed err -> do { hPutStrLn stderr (showSDoc err);
567 -- Not yet implemented in <4.11 freeStringBuffer buf;
570 -- no stmt: the line consisted of just space or comments
571 POk _ Nothing -> return Nothing;
573 POk _ (Just rdr_stmt) -> do {
575 --ToDo: can't free the string buffer until we've finished this
576 -- compilation sweep and all the identifiers have gone away.
577 --freeStringBuffer buf;
578 dumpIfSet_dyn dflags Opt_D_dump_parsed "Parser" (ppr rdr_stmt);
579 return (Just rdr_stmt)
584 %************************************************************************
586 \subsection{Initial persistent state}
588 %************************************************************************
591 initPersistentCompilerState :: IO PersistentCompilerState
592 initPersistentCompilerState
593 = do prs <- initPersistentRenamerState
595 PCS { pcs_PIT = emptyIfaceTable,
596 pcs_PTE = wiredInThingEnv,
597 pcs_insts = emptyInstEnv,
598 pcs_rules = emptyRuleBase,
603 initPersistentRenamerState :: IO PersistentRenamerState
604 = do us <- mkSplitUniqSupply 'r'
606 PRS { prsOrig = NameSupply { nsUniqs = us,
607 nsNames = initOrigNames,
609 prsDecls = (emptyNameEnv, 0),
610 prsInsts = (emptyBag, 0),
611 prsRules = (emptyBag, 0),
616 initOrigNames :: FiniteMap (ModuleName,OccName) Name
618 = grab knownKeyNames `plusFM` grab (map getName wiredInThings)
620 grab names = foldl add emptyFM names
622 = addToFM env (moduleName (nameModule name), nameOccName name) name