2 % (c) The GRASP/AQUA Project, Glasgow University, 1993-2000
5 \section[GHC_Main]{Main driver for Glasgow Haskell compiler}
10 hscMain, newHscEnv, hscCmmFile,
14 hscStmt, hscTcExpr, hscKcType,
15 hscGetInfo, GetInfoResult,
20 #include "HsVersions.h"
23 import HsSyn ( Stmt(..), LHsExpr )
24 import IfaceSyn ( IfaceDecl, IfaceInst )
25 import Module ( Module )
26 import CodeOutput ( outputForeignStubs )
27 import ByteCodeGen ( byteCodeGen, coreExprToBCOs )
28 import Linker ( HValue, linkExpr )
29 import TidyPgm ( tidyCoreExpr )
30 import CorePrep ( corePrepExpr )
31 import Flattening ( flattenExpr )
32 import TcRnDriver ( tcRnStmt, tcRnExpr, tcRnGetInfo, GetInfoResult, tcRnType )
33 import RdrName ( rdrNameOcc )
34 import OccName ( occNameUserString )
36 import PrelNames ( iNTERACTIVE )
38 import CoreLint ( lintUnfolding )
39 import DsMeta ( templateHaskellNames )
40 import BasicTypes ( Fixity )
41 import SrcLoc ( SrcLoc, noSrcLoc )
45 import Module ( emptyModuleEnv )
46 import RdrName ( GlobalRdrEnv, RdrName )
47 import HsSyn ( HsModule, LHsBinds, LStmt, LHsType, HsGroup )
48 import SrcLoc ( Located(..) )
49 import StringBuffer ( hGetStringBuffer, stringToStringBuffer )
51 import Lexer ( P(..), ParseResult(..), mkPState )
52 import SrcLoc ( mkSrcLoc )
53 import TcRnDriver ( tcRnModule, tcRnExtCore )
54 import TcIface ( typecheckIface )
55 import TcRnMonad ( initIfaceCheck, TcGblEnv(..) )
56 import IfaceEnv ( initNameCache )
57 import LoadIface ( ifaceStats, initExternalPackageState )
58 import PrelInfo ( wiredInThings, basicKnownKeyNames )
59 import MkIface ( checkOldIface, mkIface )
61 import Flattening ( flatten )
63 import TidyPgm ( tidyCorePgm )
64 import CorePrep ( corePrepPgm )
65 import CoreToStg ( coreToStg )
66 import Name ( Name, NamedThing(..) )
67 import SimplStg ( stg2stg )
68 import CodeGen ( codeGen )
69 import CmmParse ( parseCmmFile )
70 import CodeOutput ( codeOutput )
73 import DriverPhases ( HscSource(..) )
75 import UniqSupply ( mkSplitUniqSupply )
78 import HscStats ( ppSourceStats )
80 import MkExternalCore ( emitExternalCore )
82 import ParserCoreUtils
84 import Maybes ( expectJust )
85 import StringBuffer ( StringBuffer )
86 import Bag ( unitBag, emptyBag )
89 import Maybe ( isJust )
91 import DATA_IOREF ( newIORef, readIORef )
95 %************************************************************************
99 %************************************************************************
102 newHscEnv :: DynFlags -> IO HscEnv
104 = do { eps_var <- newIORef initExternalPackageState
105 ; us <- mkSplitUniqSupply 'r'
106 ; nc_var <- newIORef (initNameCache us knownKeyNames)
107 ; fc_var <- newIORef emptyModuleEnv
108 ; return (HscEnv { hsc_dflags = dflags,
111 hsc_IC = emptyInteractiveContext,
112 hsc_HPT = emptyHomePackageTable,
115 hsc_FC = fc_var } ) }
118 knownKeyNames :: [Name] -- Put here to avoid loops involving DsMeta,
119 -- where templateHaskellNames are defined
120 knownKeyNames = map getName wiredInThings
121 ++ basicKnownKeyNames
123 ++ templateHaskellNames
128 %************************************************************************
130 The main compiler pipeline
132 %************************************************************************
136 -- Compilation failed
139 -- In IDE mode: we just do the static/dynamic checks
141 (Located (HsModule RdrName)) -- parsed
142 (Maybe (HsGroup Name)) -- renamed
143 (Maybe (LHsBinds Id, GlobalRdrEnv, ModDetails)) -- typechecked
145 -- Concluded that it wasn't necessary
146 | HscNoRecomp ModDetails -- new details (HomeSymbolTable additions)
147 ModIface -- new iface (if any compilation was done)
150 | HscRecomp ModDetails -- new details (HomeSymbolTable additions)
151 ModIface -- new iface (if any compilation was done)
152 Bool -- stub_h exists
153 Bool -- stub_c exists
154 (Maybe CompiledByteCode)
157 -- What to do when we have compiler error or warning messages
158 type MessageAction = Messages -> IO ()
160 -- no errors or warnings; the individual passes
161 -- (parse/rename/typecheck) print messages themselves
165 -> MessageAction -- What to do with errors/warnings
167 -> Bool -- True <=> source unchanged
168 -> Bool -- True <=> have an object file (for msgs only)
169 -> Maybe ModIface -- Old interface, if available
170 -> Maybe (Int, Int) -- Just (i,n) <=> module i of n (for msgs)
173 hscMain hsc_env msg_act mod_summary
174 source_unchanged have_object maybe_old_iface
177 (recomp_reqd, maybe_checked_iface) <-
178 {-# SCC "checkOldIface" #-}
179 checkOldIface hsc_env mod_summary
180 source_unchanged maybe_old_iface;
182 let no_old_iface = not (isJust maybe_checked_iface)
183 what_next | recomp_reqd || no_old_iface = hscRecomp
184 | otherwise = hscNoRecomp
186 ; what_next hsc_env msg_act mod_summary have_object
192 ------------------------------
193 -- hscNoRecomp definitely expects to have the old interface available
194 hscNoRecomp hsc_env msg_act mod_summary
195 have_object (Just old_iface)
197 | isOneShot (ghcMode (hsc_dflags hsc_env))
199 compilationProgressMsg (hsc_dflags hsc_env) $
200 "compilation IS NOT required";
201 dumpIfaceStats hsc_env ;
203 let { bomb = panic "hscNoRecomp:OneShot" };
204 return (HscNoRecomp bomb bomb)
207 = do { compilationProgressMsg (hsc_dflags hsc_env) $
208 (showModuleIndex mb_mod_index ++
209 "Skipping " ++ showModMsg have_object mod_summary)
211 ; new_details <- {-# SCC "tcRnIface" #-}
212 initIfaceCheck hsc_env $
213 typecheckIface old_iface ;
214 ; dumpIfaceStats hsc_env
216 ; return (HscNoRecomp new_details old_iface)
219 ------------------------------
220 hscRecomp hsc_env msg_act mod_summary
221 have_object maybe_checked_iface
223 = case ms_hsc_src mod_summary of
225 front_res <- hscFileFrontEnd hsc_env msg_act mod_summary mb_mod_index
226 hscBackEnd hsc_env mod_summary maybe_checked_iface front_res
229 front_res <- hscFileFrontEnd hsc_env msg_act mod_summary mb_mod_index
230 hscBootBackEnd hsc_env mod_summary maybe_checked_iface front_res
233 front_res <- hscCoreFrontEnd hsc_env msg_act mod_summary
234 hscBackEnd hsc_env mod_summary maybe_checked_iface front_res
236 hscCoreFrontEnd hsc_env msg_act mod_summary = do {
240 ; inp <- readFile (expectJust "hscCoreFrontEnd" (ms_hspp_file mod_summary))
241 ; case parseCore inp 1 of
242 FailP s -> putMsg s{-ToDo: wrong-} >> return Nothing
243 OkP rdr_module -> do {
246 -- RENAME and TYPECHECK
248 ; (tc_msgs, maybe_tc_result) <- {-# SCC "TypeCheck" #-}
249 tcRnExtCore hsc_env rdr_module
251 ; case maybe_tc_result of
252 Nothing -> return Nothing
253 Just mod_guts -> return (Just mod_guts) -- No desugaring to do!
257 hscFileFrontEnd hsc_env msg_act mod_summary mb_mod_index = do {
259 -- DISPLAY PROGRESS MESSAGE
261 let one_shot = isOneShot (ghcMode (hsc_dflags hsc_env))
262 ; let dflags = hsc_dflags hsc_env
263 ; let toInterp = hscTarget dflags == HscInterpreted
264 ; when (not one_shot) $
265 compilationProgressMsg dflags $
266 (showModuleIndex mb_mod_index ++
267 "Compiling " ++ showModMsg (not toInterp) mod_summary)
272 ; let hspp_file = expectJust "hscFileFrontEnd" (ms_hspp_file mod_summary)
273 hspp_buf = ms_hspp_buf mod_summary
275 ; maybe_parsed <- myParseModule (hsc_dflags hsc_env) hspp_file hspp_buf
277 ; case maybe_parsed of {
278 Left err -> do { msg_act (unitBag err, emptyBag)
280 Right rdr_module -> do {
283 -- RENAME and TYPECHECK
285 (tc_msgs, maybe_tc_result)
286 <- {-# SCC "Typecheck-Rename" #-}
287 tcRnModule hsc_env (ms_hsc_src mod_summary) False rdr_module
290 ; case maybe_tc_result of {
291 Nothing -> return Nothing ;
292 Just tc_result -> do {
297 ; (warns, maybe_ds_result) <- {-# SCC "DeSugar" #-}
298 deSugar hsc_env tc_result
299 ; msg_act (warns, emptyBag)
300 ; case maybe_ds_result of
301 Nothing -> return Nothing
302 Just ds_result -> return (Just ds_result)
305 ------------------------------
307 hscFileCheck :: HscEnv -> MessageAction -> ModSummary -> IO HscResult
308 hscFileCheck hsc_env msg_act mod_summary = do {
312 ; let hspp_file = expectJust "hscFileFrontEnd" (ms_hspp_file mod_summary)
313 hspp_buf = ms_hspp_buf mod_summary
315 ; maybe_parsed <- myParseModule (hsc_dflags hsc_env) hspp_file hspp_buf
317 ; case maybe_parsed of {
318 Left err -> do { msg_act (unitBag err, emptyBag)
320 Right rdr_module -> do {
323 -- RENAME and TYPECHECK
325 (tc_msgs, maybe_tc_result)
326 <- _scc_ "Typecheck-Rename"
327 tcRnModule hsc_env (ms_hsc_src mod_summary)
328 True{-save renamed syntax-}
332 ; case maybe_tc_result of {
333 Nothing -> return (HscChecked rdr_module Nothing Nothing);
335 let md = ModDetails {
336 md_types = tcg_type_env tc_result,
337 md_exports = tcg_exports tc_result,
338 md_insts = tcg_insts tc_result,
339 md_rules = [panic "no rules"] }
340 -- rules are IdCoreRules, not the
341 -- RuleDecls we get out of the typechecker
342 return (HscChecked rdr_module
343 (tcg_rn_decls tc_result)
344 (Just (tcg_binds tc_result,
345 tcg_rdr_env tc_result,
349 ------------------------------
350 hscBootBackEnd :: HscEnv -> ModSummary -> Maybe ModIface -> Maybe ModGuts -> IO HscResult
351 -- For hs-boot files, there's no code generation to do
353 hscBootBackEnd hsc_env mod_summary maybe_checked_iface Nothing
355 hscBootBackEnd hsc_env mod_summary maybe_checked_iface (Just ds_result)
356 = do { final_iface <- {-# SCC "MkFinalIface" #-}
357 mkIface hsc_env (ms_location mod_summary)
358 maybe_checked_iface ds_result
360 ; let { final_details = ModDetails { md_types = mg_types ds_result,
361 md_exports = mg_exports ds_result,
362 md_insts = mg_insts ds_result,
363 md_rules = mg_rules ds_result } }
364 -- And the answer is ...
365 ; dumpIfaceStats hsc_env
367 ; return (HscRecomp final_details
372 ------------------------------
373 hscBackEnd :: HscEnv -> ModSummary -> Maybe ModIface -> Maybe ModGuts -> IO HscResult
375 hscBackEnd hsc_env mod_summary maybe_checked_iface Nothing
378 hscBackEnd hsc_env mod_summary maybe_checked_iface (Just ds_result)
380 -- ; seqList imported_modules (return ())
382 let one_shot = isOneShot (ghcMode dflags)
383 dflags = hsc_dflags hsc_env
388 ; flat_result <- {-# SCC "Flattening" #-}
389 flatten hsc_env ds_result
392 {- TEMP: need to review space-leak fixing here
393 NB: even the code generator can force one of the
394 thunks for constructor arguments, for newtypes in particular
396 ; let -- Rule-base accumulated from imported packages
397 pkg_rule_base = eps_rule_base (hsc_EPS hsc_env)
399 -- In one-shot mode, ZAP the external package state at
400 -- this point, because we aren't going to need it from
401 -- now on. We keep the name cache, however, because
402 -- tidyCore needs it.
404 | one_shot = pcs_tc{ pcs_EPS = error "pcs_EPS missing" }
407 ; pkg_rule_base `seq` pcs_middle `seq` return ()
410 -- alive at this point:
418 ; simpl_result <- {-# SCC "Core2Core" #-}
419 core2core hsc_env flat_result
424 ; tidy_result <- {-# SCC "CoreTidy" #-}
425 tidyCorePgm hsc_env simpl_result
427 -- Emit external core
428 ; emitExternalCore dflags tidy_result
430 -- Alive at this point:
431 -- tidy_result, pcs_final
435 -- BUILD THE NEW ModIface and ModDetails
436 -- and emit external core if necessary
437 -- This has to happen *after* code gen so that the back-end
438 -- info has been set. Not yet clear if it matters waiting
439 -- until after code output
440 ; new_iface <- {-# SCC "MkFinalIface" #-}
441 mkIface hsc_env (ms_location mod_summary)
442 maybe_checked_iface tidy_result
444 -- Space leak reduction: throw away the new interface if
445 -- we're in one-shot mode; we won't be needing it any
448 if one_shot then return (error "no final iface")
449 else return new_iface
451 -- Build the final ModDetails (except in one-shot mode, where
452 -- we won't need this information after compilation).
454 if one_shot then return (error "no final details")
455 else return $! ModDetails {
456 md_types = mg_types tidy_result,
457 md_exports = mg_exports tidy_result,
458 md_insts = mg_insts tidy_result,
459 md_rules = mg_rules tidy_result }
462 -- CONVERT TO STG and COMPLETE CODE GENERATION
463 ; (stub_h_exists, stub_c_exists, maybe_bcos)
464 <- hscCodeGen dflags tidy_result
466 -- And the answer is ...
467 ; dumpIfaceStats hsc_env
469 ; return (HscRecomp final_details
471 stub_h_exists stub_c_exists
478 ModGuts{ -- This is the last use of the ModGuts in a compilation.
479 -- From now on, we just use the bits we need.
480 mg_module = this_mod,
481 mg_binds = core_binds,
483 mg_dir_imps = dir_imps,
484 mg_foreign = foreign_stubs,
485 mg_deps = dependencies } = do {
488 -- PREPARE FOR CODE GENERATION
489 -- Do saturation and convert to A-normal form
490 prepd_binds <- {-# SCC "CorePrep" #-}
491 corePrepPgm dflags core_binds type_env;
493 case hscTarget dflags of
494 HscNothing -> return (False, False, Nothing)
498 do ----------------- Generate byte code ------------------
499 comp_bc <- byteCodeGen dflags prepd_binds type_env
501 ------------------ Create f-x-dynamic C-side stuff ---
502 (istub_h_exists, istub_c_exists)
503 <- outputForeignStubs dflags foreign_stubs
505 return ( istub_h_exists, istub_c_exists, Just comp_bc )
507 panic "GHC not compiled with interpreter"
512 ----------------- Convert to STG ------------------
513 (stg_binds, cost_centre_info) <- {-# SCC "CoreToStg" #-}
514 myCoreToStg dflags this_mod prepd_binds
516 ------------------ Code generation ------------------
517 abstractC <- {-# SCC "CodeGen" #-}
518 codeGen dflags this_mod type_env foreign_stubs
519 dir_imps cost_centre_info stg_binds
521 ------------------ Code output -----------------------
522 (stub_h_exists, stub_c_exists)
523 <- codeOutput dflags this_mod foreign_stubs
524 dependencies abstractC
526 return (stub_h_exists, stub_c_exists, Nothing)
530 hscCmmFile :: DynFlags -> FilePath -> IO Bool
531 hscCmmFile dflags filename = do
532 maybe_cmm <- parseCmmFile dflags filename
534 Nothing -> return False
536 codeOutput dflags no_mod NoStubs noDependencies [cmm]
539 no_mod = panic "hscCmmFile: no_mod"
542 myParseModule dflags src_filename maybe_src_buf
543 = -------------------------- Parser ----------------
544 showPass dflags "Parser" >>
545 {-# SCC "Parser" #-} do
547 -- sometimes we already have the buffer in memory, perhaps
548 -- because we needed to parse the imports out of it, or get the
550 buf <- case maybe_src_buf of
552 Nothing -> hGetStringBuffer src_filename
554 let loc = mkSrcLoc (mkFastString src_filename) 1 0
556 case unP parseModule (mkPState buf loc dflags) of {
558 PFailed span err -> return (Left (mkPlainErrMsg span err));
560 POk _ rdr_module -> do {
562 dumpIfSet_dyn dflags Opt_D_dump_parsed "Parser" (ppr rdr_module) ;
564 dumpIfSet_dyn dflags Opt_D_source_stats "Source Statistics"
565 (ppSourceStats False rdr_module) ;
567 return (Right rdr_module)
568 -- ToDo: free the string buffer later.
572 myCoreToStg dflags this_mod prepd_binds
574 stg_binds <- {-# SCC "Core2Stg" #-}
575 coreToStg dflags prepd_binds
577 (stg_binds2, cost_centre_info) <- {-# SCC "Core2Stg" #-}
578 stg2stg dflags this_mod stg_binds
580 return (stg_binds2, cost_centre_info)
584 %************************************************************************
586 \subsection{Compiling a do-statement}
588 %************************************************************************
590 When the UnlinkedBCOExpr is linked you get an HValue of type
592 When you run it you get a list of HValues that should be
593 the same length as the list of names; add them to the ClosureEnv.
595 A naked expression returns a singleton Name [it].
597 What you type The IO [HValue] that hscStmt returns
598 ------------- ------------------------------------
599 let pat = expr ==> let pat = expr in return [coerce HVal x, coerce HVal y, ...]
602 pat <- expr ==> expr >>= \ pat -> return [coerce HVal x, coerce HVal y, ...]
605 expr (of IO type) ==> expr >>= \ v -> return [v]
606 [NB: result not printed] bindings: [it]
609 expr (of non-IO type,
610 result showable) ==> let v = expr in print v >> return [v]
613 expr (of non-IO type,
614 result not showable) ==> error
618 hscStmt -- Compile a stmt all the way to an HValue, but don't run it
620 -> String -- The statement
621 -> IO (Maybe (HscEnv, [Name], HValue))
624 = do { maybe_stmt <- hscParseStmt (hsc_dflags hsc_env) stmt
625 ; case maybe_stmt of {
626 Nothing -> return Nothing ; -- Parse error
627 Just Nothing -> return Nothing ; -- Empty line
628 Just (Just parsed_stmt) -> do { -- The real stuff
630 -- Rename and typecheck it
631 let icontext = hsc_IC hsc_env
632 ; maybe_tc_result <- tcRnStmt hsc_env icontext parsed_stmt
634 ; case maybe_tc_result of {
635 Nothing -> return Nothing ;
636 Just (new_ic, bound_names, tc_expr) -> do {
638 -- Then desugar, code gen, and link it
639 ; hval <- compileExpr hsc_env iNTERACTIVE
640 (ic_rn_gbl_env new_ic)
644 ; return (Just (hsc_env{ hsc_IC=new_ic }, bound_names, hval))
647 hscTcExpr -- Typecheck an expression (but don't run it)
649 -> String -- The expression
652 hscTcExpr hsc_env expr
653 = do { maybe_stmt <- hscParseStmt (hsc_dflags hsc_env) expr
654 ; let icontext = hsc_IC hsc_env
655 ; case maybe_stmt of {
656 Nothing -> return Nothing ; -- Parse error
657 Just (Just (L _ (ExprStmt expr _ _)))
658 -> tcRnExpr hsc_env icontext expr ;
659 Just other -> do { errorMsg ("not an expression: `" ++ expr ++ "'") ;
663 hscKcType -- Find the kind of a type
665 -> String -- The type
668 hscKcType hsc_env str
669 = do { maybe_type <- hscParseType (hsc_dflags hsc_env) str
670 ; let icontext = hsc_IC hsc_env
671 ; case maybe_type of {
672 Just ty -> tcRnType hsc_env icontext ty ;
673 Just other -> do { errorMsg ("not an type: `" ++ str ++ "'") ;
675 Nothing -> return Nothing } }
680 hscParseStmt :: DynFlags -> String -> IO (Maybe (Maybe (LStmt RdrName)))
681 hscParseStmt = hscParseThing parseStmt
683 hscParseType :: DynFlags -> String -> IO (Maybe (LHsType RdrName))
684 hscParseType = hscParseThing parseType
686 hscParseIdentifier :: DynFlags -> String -> IO (Maybe (Located RdrName))
687 hscParseIdentifier = hscParseThing parseIdentifier
689 hscParseThing :: Outputable thing
691 -> DynFlags -> String
693 -- Nothing => Parse error (message already printed)
695 hscParseThing parser dflags str
696 = showPass dflags "Parser" >>
697 {-# SCC "Parser" #-} do
699 buf <- stringToStringBuffer str
701 let loc = mkSrcLoc FSLIT("<interactive>") 1 0
703 case unP parser (mkPState buf loc dflags) of {
705 PFailed span err -> do { printError span err;
710 --ToDo: can't free the string buffer until we've finished this
711 -- compilation sweep and all the identifiers have gone away.
712 dumpIfSet_dyn dflags Opt_D_dump_parsed "Parser" (ppr thing);
717 %************************************************************************
719 \subsection{Getting information about an identifer}
721 %************************************************************************
725 hscGetInfo -- like hscStmt, but deals with a single identifier
727 -> String -- The identifier
728 -> IO [GetInfoResult]
730 hscGetInfo hsc_env str
731 = do maybe_rdr_name <- hscParseIdentifier (hsc_dflags hsc_env) str
732 case maybe_rdr_name of {
733 Nothing -> return [];
734 Just (L _ rdr_name) -> do
736 maybe_tc_result <- tcRnGetInfo hsc_env (hsc_IC hsc_env) rdr_name
738 case maybe_tc_result of
740 Just things -> return things
745 %************************************************************************
747 Desugar, simplify, convert to bytecode, and link an expression
749 %************************************************************************
753 compileExpr :: HscEnv
754 -> Module -> GlobalRdrEnv -> TypeEnv
758 compileExpr hsc_env this_mod rdr_env type_env tc_expr
759 = do { let { dflags = hsc_dflags hsc_env ;
760 lint_on = dopt Opt_DoCoreLinting dflags }
763 ; ds_expr <- deSugarExpr hsc_env this_mod rdr_env type_env tc_expr
766 ; flat_expr <- flattenExpr hsc_env ds_expr
769 ; simpl_expr <- simplifyExpr dflags flat_expr
771 -- Tidy it (temporary, until coreSat does cloning)
772 ; tidy_expr <- tidyCoreExpr simpl_expr
774 -- Prepare for codegen
775 ; prepd_expr <- corePrepExpr dflags tidy_expr
778 -- ToDo: improve SrcLoc
780 case lintUnfolding noSrcLoc [] prepd_expr of
781 Just err -> pprPanic "compileExpr" err
787 ; bcos <- coreExprToBCOs dflags prepd_expr
790 ; hval <- linkExpr hsc_env bcos
798 %************************************************************************
800 Statistics on reading interfaces
802 %************************************************************************
805 dumpIfaceStats :: HscEnv -> IO ()
806 dumpIfaceStats hsc_env
807 = do { eps <- readIORef (hsc_EPS hsc_env)
808 ; dumpIfSet (dump_if_trace || dump_rn_stats)
809 "Interface statistics"
812 dflags = hsc_dflags hsc_env
813 dump_rn_stats = dopt Opt_D_dump_rn_stats dflags
814 dump_if_trace = dopt Opt_D_dump_if_trace dflags
817 %************************************************************************
819 Progress Messages: Module i of n
821 %************************************************************************
824 showModuleIndex Nothing = ""
825 showModuleIndex (Just (i,n)) = "[" ++ padded ++ " of " ++ n_str ++ "] "
829 padded = replicate (length n_str - length i_str) ' ' ++ i_str