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 ByteCodeGen ( byteCodeGen )
17 import CoreTidy ( tidyCoreExpr )
18 import CorePrep ( corePrepExpr )
19 import Rename ( renameStmt )
20 import RdrHsSyn ( RdrNameStmt )
22 import Id ( Id, idName, setGlobalIdDetails )
23 import IdInfo ( GlobalIdDetails(VanillaGlobal) )
24 import HscTypes ( InteractiveContext(..), TyThing(..) )
25 import PrelNames ( iNTERACTIVE )
26 import StringBuffer ( stringToStringBuffer )
32 import IdInfo ( CafInfo(..), CgInfoEnv, CgInfo(..) )
33 import StringBuffer ( hGetStringBuffer, freeStringBuffer )
35 import Lex ( PState(..), ParseResult(..) )
36 import SrcLoc ( mkSrcLoc )
37 import Rename ( checkOldIface, renameModule, closeIfaceDecls )
38 import Rules ( emptyRuleBase )
39 import PrelInfo ( wiredInThingEnv, wiredInThings )
40 import PrelNames ( vanillaSyntaxMap, knownKeyNames )
41 import MkIface ( completeIface, writeIface, pprIface )
43 import InstEnv ( emptyInstEnv )
46 import CoreUtils ( coreBindsSize )
47 import CoreTidy ( tidyCorePgm )
48 import CorePrep ( corePrepPgm )
50 import CoreToStg ( coreToStg )
51 import SimplStg ( stg2stg )
52 import CodeGen ( codeGen )
53 import CodeOutput ( codeOutput )
55 import Module ( ModuleName, moduleName, mkHomeModule,
58 import ErrUtils ( dumpIfSet_dyn, showPass, printError )
59 import Util ( unJust )
60 import UniqSupply ( mkSplitUniqSupply )
62 import Bag ( emptyBag )
65 import CmStaticInfo ( GhciMode(..) )
66 import HscStats ( ppSourceStats )
68 import FiniteMap ( FiniteMap, plusFM, emptyFM, addToFM )
69 import OccName ( OccName )
70 import Name ( Name, nameModule, nameOccName, getName, isGlobalName )
71 import NameEnv ( emptyNameEnv, mkNameEnv )
72 import Module ( Module, lookupModuleEnvByName )
73 import Maybes ( orElse )
75 import IOExts ( newIORef, readIORef, writeIORef, unsafePerformIO )
78 import Maybe ( isJust )
83 %************************************************************************
85 \subsection{The main compiler pipeline}
87 %************************************************************************
92 = HscFail PersistentCompilerState -- updated PCS
93 -- concluded that it wasn't necessary
94 | HscNoRecomp PersistentCompilerState -- updated PCS
95 ModDetails -- new details (HomeSymbolTable additions)
96 ModIface -- new iface (if any compilation was done)
98 | HscRecomp PersistentCompilerState -- updated PCS
99 ModDetails -- new details (HomeSymbolTable additions)
100 ModIface -- new iface (if any compilation was done)
101 (Maybe String) -- generated stub_h filename (in TMPDIR)
102 (Maybe String) -- generated stub_c filename (in TMPDIR)
103 (Maybe ([UnlinkedBCO],ItblEnv)) -- interpreted code, if any
106 -- no errors or warnings; the individual passes
107 -- (parse/rename/typecheck) print messages themselves
113 -> ModuleLocation -- location info
114 -> Bool -- source unchanged?
115 -> Maybe ModIface -- old interface, if available
116 -> HomeSymbolTable -- for home module ModDetails
118 -> PersistentCompilerState -- IN: persistent compiler state
121 hscMain ghci_mode dflags mod location source_unchanged maybe_old_iface hst hit pcs
123 showPass dflags ("Checking old interface for hs = "
124 ++ show (ml_hs_file location)
125 ++ ", hspp = " ++ show (ml_hspp_file location));
127 (pcs_ch, errs_found, (recomp_reqd, maybe_checked_iface))
128 <- checkOldIface ghci_mode dflags hit hst pcs
129 (unJust "hscMain" (ml_hi_file location))
130 source_unchanged maybe_old_iface;
133 return (HscFail pcs_ch)
136 let no_old_iface = not (isJust maybe_checked_iface)
137 what_next | recomp_reqd || no_old_iface = hscRecomp
138 | otherwise = hscNoRecomp
140 what_next ghci_mode dflags mod location maybe_checked_iface
145 -- we definitely expect to have the old interface available
146 hscNoRecomp ghci_mode dflags mod location (Just old_iface) hst hit pcs_ch
147 | ghci_mode == OneShot
149 hPutStrLn stderr "compilation IS NOT required";
150 let { bomb = panic "hscNoRecomp:OneShot" };
151 return (HscNoRecomp pcs_ch bomb bomb)
155 when (verbosity dflags >= 1) $
156 hPutStrLn stderr ("Skipping " ++ compMsg mod location);
159 (pcs_cl, closure_errs, cl_hs_decls)
160 <- closeIfaceDecls dflags hit hst pcs_ch old_iface ;
162 return (HscFail pcs_cl)
167 <- typecheckIface dflags pcs_cl hst old_iface (vanillaSyntaxMap, cl_hs_decls);
169 case maybe_tc_result of {
170 Nothing -> return (HscFail pcs_cl);
171 Just (pcs_tc, new_details) ->
173 return (HscNoRecomp pcs_tc new_details old_iface)
176 compMsg mod location =
177 mod_str ++ take (max 0 (16 - length mod_str)) (repeat ' ')
178 ++ " (" ++ unJust "hscRecomp" (ml_hs_file location) ++ ")"
179 where mod_str = moduleUserString mod
182 hscRecomp ghci_mode dflags mod location maybe_checked_iface hst hit pcs_ch
184 ; when (verbosity dflags >= 1) $
185 hPutStrLn stderr ("Compiling " ++ compMsg mod location);
187 -- what target are we shooting for?
188 ; let toInterp = dopt_HscLang dflags == HscInterpreted
193 ; maybe_parsed <- myParseModule dflags
194 (unJust "hscRecomp:hspp" (ml_hspp_file location))
195 ; case maybe_parsed of {
196 Nothing -> return (HscFail pcs_ch);
197 Just rdr_module -> do {
198 ; let this_mod = mkHomeModule (hsModuleName rdr_module)
203 ; (pcs_rn, print_unqualified, maybe_rn_result)
205 renameModule dflags hit hst pcs_ch this_mod rdr_module
206 ; case maybe_rn_result of {
207 Nothing -> return (HscFail pcs_ch{-was: pcs_rn-});
208 Just (is_exported, new_iface, rn_hs_decls) -> do {
210 -- In interactive mode, we don't want to discard any top-level entities at
211 -- all (eg. do not inline them away during simplification), and retain them
212 -- all in the TypeEnv so they are available from the command line.
214 -- isGlobalName separates the user-defined top-level names from those
215 -- introduced by the type checker.
216 ; let dont_discard | ghci_mode == Interactive = isGlobalName
217 | otherwise = is_exported
223 <- _scc_ "TypeCheck" typecheckModule dflags pcs_rn hst new_iface
224 print_unqualified rn_hs_decls
225 ; case maybe_tc_result of {
226 Nothing -> return (HscFail pcs_ch{-was: pcs_rn-});
227 Just (pcs_tc, tc_result) -> do {
232 ; (ds_details, foreign_stuff)
234 deSugar dflags pcs_tc hst this_mod print_unqualified tc_result
241 core2core dflags pcs_tc hst dont_discard ds_details
246 ; cg_info_ref <- newIORef Nothing ;
247 ; let cg_info :: CgInfoEnv
248 cg_info = unsafePerformIO $ do {
249 maybe_cg_env <- readIORef cg_info_ref ;
251 Just env -> return env
252 Nothing -> do { printError "Urk! Looked at CgInfo too early!";
253 return emptyNameEnv } }
254 -- cg_info_ref will be filled in just after restOfCodeGeneration
255 -- Meanwhile, tidyCorePgm is careful not to look at cg_info!
257 ; (pcs_simpl, tidy_details)
258 <- tidyCorePgm dflags this_mod pcs_tc cg_info simpl_details
261 -- PREPARE FOR CODE GENERATION
263 -- Do saturation and convert to A-normal form
264 ; prepd_details <- corePrepPgm dflags tidy_details
267 -- CONVERT TO STG and COMPLETE CODE GENERATION
270 ModDetails{md_binds=binds, md_types=env_tc} = prepd_details
272 local_tycons = typeEnvTyCons env_tc
273 local_classes = typeEnvClasses env_tc
275 imported_module_names = map ideclName (hsModuleImports rdr_module)
276 imported_modules = map mod_name_to_Module imported_module_names
278 (h_code,c_code,fe_binders) = foreign_stuff
280 pit = pcs_PIT pcs_simpl
282 mod_name_to_Module :: ModuleName -> Module
283 mod_name_to_Module nm
284 = let str_mi = lookupModuleEnvByName hit nm `orElse`
285 lookupModuleEnvByName pit nm `orElse`
286 pprPanic "mod_name_to_Module: no hst or pst mapping for"
290 ; (maybe_stub_h_filename, maybe_stub_c_filename,
291 maybe_bcos, final_iface )
294 ----------------- Generate byte code ------------------
295 (bcos,itbl_env) <- byteCodeGen dflags binds
296 local_tycons local_classes
298 -- Fill in the code-gen info
299 writeIORef cg_info_ref (Just emptyNameEnv)
301 ------------------ BUILD THE NEW ModIface ------------
302 final_iface <- _scc_ "MkFinalIface"
303 mkFinalIface ghci_mode dflags location
304 maybe_checked_iface new_iface tidy_details
306 return ( Nothing, Nothing,
307 Just (bcos,itbl_env), final_iface )
310 ----------------- Convert to STG ------------------
311 (stg_binds, cost_centre_info, stg_back_end_info)
313 myCoreToStg dflags this_mod binds
315 -- Fill in the code-gen info for the earlier tidyCorePgm
316 writeIORef cg_info_ref (Just stg_back_end_info)
318 ------------------ BUILD THE NEW ModIface ------------
319 final_iface <- _scc_ "MkFinalIface"
320 mkFinalIface ghci_mode dflags location
321 maybe_checked_iface new_iface tidy_details
323 ------------------ Code generation ------------------
324 abstractC <- _scc_ "CodeGen"
325 codeGen dflags this_mod imported_modules
326 cost_centre_info fe_binders
327 local_tycons stg_binds
329 ------------------ Code output -----------------------
330 (maybe_stub_h_name, maybe_stub_c_name)
331 <- codeOutput dflags this_mod local_tycons
333 c_code h_code abstractC
335 return ( maybe_stub_h_name, maybe_stub_c_name,
336 Nothing, final_iface )
338 ; let final_details = tidy_details {md_binds = []}
341 -- and the answer is ...
342 ; return (HscRecomp pcs_simpl
345 maybe_stub_h_filename maybe_stub_c_filename
351 mkFinalIface ghci_mode dflags location
352 maybe_old_iface new_iface new_details
353 = case completeIface maybe_old_iface new_iface new_details of
355 (new_iface, Nothing) -- no change in the interfacfe
356 -> do when (dopt Opt_D_dump_hi_diffs dflags)
357 (printDump (text "INTERFACE UNCHANGED"))
358 dumpIfSet_dyn dflags Opt_D_dump_hi
359 "UNCHANGED FINAL INTERFACE" (pprIface new_iface)
362 (new_iface, Just sdoc_diffs)
363 -> do dumpIfSet_dyn dflags Opt_D_dump_hi_diffs "INTERFACE HAS CHANGED"
365 dumpIfSet_dyn dflags Opt_D_dump_hi "NEW FINAL INTERFACE"
368 -- Write the interface file, if not in interactive mode
369 when (ghci_mode /= Interactive)
370 (writeIface (unJust "hscRecomp:hi" (ml_hi_file location))
375 myParseModule dflags src_filename
376 = do -------------------------- Parser ----------------
377 showPass dflags "Parser"
380 buf <- hGetStringBuffer True{-expand tabs-} src_filename
382 let glaexts | dopt Opt_GlasgowExts dflags = 1#
385 case parseModule buf PState{ bol = 0#, atbol = 1#,
386 context = [], glasgow_exts = glaexts,
387 loc = mkSrcLoc (_PK_ src_filename) 1 } of {
389 PFailed err -> do { hPutStrLn stderr (showSDoc err);
390 freeStringBuffer buf;
393 POk _ rdr_module@(HsModule mod_name _ _ _ _ _ _) -> do {
395 dumpIfSet_dyn dflags Opt_D_dump_parsed "Parser" (ppr rdr_module) ;
397 dumpIfSet_dyn dflags Opt_D_source_stats "Source Statistics"
398 (ppSourceStats False rdr_module) ;
400 return (Just rdr_module)
401 -- ToDo: free the string buffer later.
405 myCoreToStg dflags this_mod tidy_binds
407 () <- coreBindsSize tidy_binds `seq` return ()
408 -- TEMP: the above call zaps some space usage allocated by the
409 -- simplifier, which for reasons I don't understand, persists
410 -- thoroughout code generation
412 stg_binds <- _scc_ "Core2Stg" coreToStg dflags tidy_binds
414 (stg_binds2, cost_centre_info)
415 <- _scc_ "Core2Stg" stg2stg dflags this_mod stg_binds
417 let env_rhs :: CgInfoEnv
418 env_rhs = mkNameEnv [ (idName bndr, CgInfo (stgRhsArity rhs) caf_info)
419 | (bind,_) <- stg_binds2,
421 | stgBindHasCafRefs bind = MayHaveCafRefs
422 | otherwise = NoCafRefs,
423 (bndr,rhs) <- stgBindPairs bind ]
425 return (stg_binds2, cost_centre_info, env_rhs)
427 stgBindPairs (StgNonRec _ b r) = [(b,r)]
428 stgBindPairs (StgRec _ prs) = prs
432 %************************************************************************
434 \subsection{Compiling a do-statement}
436 %************************************************************************
444 -> PersistentCompilerState -- IN: persistent compiler state
445 -> InteractiveContext -- Context for compiling
446 -> String -- The statement
447 -> Bool -- just treat it as an expression
448 -> IO ( PersistentCompilerState,
454 When the UnlinkedBCOExpr is linked you get an HValue of type
456 When you run it you get a list of HValues that should be
457 the same length as the list of names; add them to the ClosureEnv.
459 A naked expression returns a singleton Name [it].
461 What you type The IO [HValue] that hscStmt returns
462 ------------- ------------------------------------
463 let pat = expr ==> let pat = expr in return [coerce HVal x, coerce HVal y, ...]
466 pat <- expr ==> expr >>= \ pat -> return [coerce HVal x, coerce HVal y, ...]
469 expr (of IO type) ==> expr >>= \ v -> return [v]
470 [NB: result not printed] bindings: [it]
473 expr (of non-IO type,
474 result showable) ==> let v = expr in print v >> return [v]
477 expr (of non-IO type,
478 result not showable) ==> error
481 hscStmt dflags hst hit pcs0 icontext stmt just_expr
485 ic_type_env = type_env,
486 ic_module = scope_mod } = icontext
488 do { maybe_stmt <- hscParseStmt dflags stmt
490 Nothing -> return (pcs0, Nothing)
491 Just parsed_stmt -> do {
493 let { notExprStmt (ExprStmt _ _) = False;
497 if (just_expr && notExprStmt parsed_stmt)
498 then do hPutStrLn stderr ("not an expression: `" ++ stmt ++ "'")
499 return (pcs0, Nothing)
503 (pcs1, print_unqual, maybe_renamed_stmt)
504 <- renameStmt dflags hit hst pcs0 scope_mod
505 iNTERACTIVE rn_env parsed_stmt
507 ; case maybe_renamed_stmt of
508 Nothing -> return (pcs0, Nothing)
509 Just (bound_names, rn_stmt) -> do {
514 then case rn_stmt of { (syn, ExprStmt e _, decls) ->
515 typecheckExpr dflags pcs1 hst type_env
516 print_unqual iNTERACTIVE (syn,e,decls) }
517 else typecheckStmt dflags pcs1 hst type_env
518 print_unqual iNTERACTIVE bound_names rn_stmt
520 ; case maybe_tc_return of
521 Nothing -> return (pcs0, Nothing)
522 Just (pcs2, tc_expr, bound_ids, ty) -> do {
525 ds_expr <- deSugarExpr dflags pcs2 hst iNTERACTIVE print_unqual tc_expr
528 ; simpl_expr <- simplifyExpr dflags pcs2 hst ds_expr
530 -- Tidy it (temporary, until coreSat does cloning)
531 ; tidy_expr <- tidyCoreExpr simpl_expr
533 -- Prepare for codegen
534 ; prepd_expr <- corePrepExpr dflags tidy_expr
537 ; bcos <- coreExprToBCOs dflags prepd_expr
540 -- Make all the bound ids "global" ids, now that
541 -- they're notionally top-level bindings. This is
542 -- important: otherwise when we come to compile an expression
543 -- using these ids later, the byte code generator will consider
544 -- the occurrences to be free rather than global.
545 global_bound_ids = map globaliseId bound_ids;
546 globaliseId id = setGlobalIdDetails id VanillaGlobal
548 ; return (pcs2, Just (global_bound_ids, ty, bcos))
552 hscParseStmt :: DynFlags -> String -> IO (Maybe RdrNameStmt)
553 hscParseStmt dflags str
554 = do -------------------------- Parser ----------------
555 showPass dflags "Parser"
558 buf <- stringToStringBuffer str
560 let glaexts | dopt Opt_GlasgowExts dflags = 1#
563 case parseStmt buf PState{ bol = 0#, atbol = 1#,
564 context = [], glasgow_exts = glaexts,
565 loc = mkSrcLoc SLIT("<no file>") 0 } of {
567 PFailed err -> do { hPutStrLn stderr (showSDoc err);
568 -- Not yet implemented in <4.11 freeStringBuffer buf;
571 -- no stmt: the line consisted of just space or comments
572 POk _ Nothing -> return Nothing;
574 POk _ (Just rdr_stmt) -> do {
576 --ToDo: can't free the string buffer until we've finished this
577 -- compilation sweep and all the identifiers have gone away.
578 --freeStringBuffer buf;
579 dumpIfSet_dyn dflags Opt_D_dump_parsed "Parser" (ppr rdr_stmt);
580 return (Just rdr_stmt)
585 %************************************************************************
587 \subsection{Initial persistent state}
589 %************************************************************************
592 initPersistentCompilerState :: IO PersistentCompilerState
593 initPersistentCompilerState
594 = do prs <- initPersistentRenamerState
596 PCS { pcs_PIT = emptyIfaceTable,
597 pcs_PTE = wiredInThingEnv,
598 pcs_insts = emptyInstEnv,
599 pcs_rules = emptyRuleBase,
604 initPersistentRenamerState :: IO PersistentRenamerState
605 = do us <- mkSplitUniqSupply 'r'
607 PRS { prsOrig = NameSupply { nsUniqs = us,
608 nsNames = initOrigNames,
610 prsDecls = (emptyNameEnv, 0),
611 prsInsts = (emptyBag, 0),
612 prsRules = (emptyBag, 0),
617 initOrigNames :: FiniteMap (ModuleName,OccName) Name
619 = grab knownKeyNames `plusFM` grab (map getName wiredInThings)
621 grab names = foldl add emptyFM names
623 = addToFM env (moduleName (nameModule name), nameOccName name) name
626 initRules :: PackageRuleBase
627 initRules = emptyRuleBase
629 foldl add emptyVarEnv builtinRules
632 = extendRuleBase env name rule