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 )
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 TcRnTypes ( TcGblEnv(..) )
55 import TcIface ( typecheckIface )
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
140 | HscChecked (Located (HsModule RdrName)) (Maybe (LHsBinds Id, GlobalRdrEnv))
142 -- Concluded that it wasn't necessary
143 | HscNoRecomp ModDetails -- new details (HomeSymbolTable additions)
144 ModIface -- new iface (if any compilation was done)
147 | HscRecomp ModDetails -- new details (HomeSymbolTable additions)
148 ModIface -- new iface (if any compilation was done)
149 Bool -- stub_h exists
150 Bool -- stub_c exists
151 (Maybe CompiledByteCode)
154 -- What to do when we have compiler error or warning messages
155 type MessageAction = Messages -> IO ()
157 -- no errors or warnings; the individual passes
158 -- (parse/rename/typecheck) print messages themselves
162 -> MessageAction -- What to do with errors/warnings
164 -> Bool -- True <=> source unchanged
165 -> Bool -- True <=> have an object file (for msgs only)
166 -> Maybe ModIface -- Old interface, if available
169 hscMain hsc_env msg_act mod_summary
170 source_unchanged have_object maybe_old_iface
172 (recomp_reqd, maybe_checked_iface) <-
173 {-# SCC "checkOldIface" #-}
174 checkOldIface hsc_env mod_summary
175 source_unchanged maybe_old_iface;
177 let no_old_iface = not (isJust maybe_checked_iface)
178 what_next | recomp_reqd || no_old_iface = hscRecomp
179 | otherwise = hscNoRecomp
181 ; what_next hsc_env msg_act mod_summary have_object
186 ------------------------------
187 -- hscNoRecomp definitely expects to have the old interface available
188 hscNoRecomp hsc_env msg_act mod_summary
189 have_object (Just old_iface)
190 | isOneShot (ghcMode (hsc_dflags hsc_env))
192 compilationProgressMsg (hsc_dflags hsc_env) $
193 "compilation IS NOT required";
194 dumpIfaceStats hsc_env ;
196 let { bomb = panic "hscNoRecomp:OneShot" };
197 return (HscNoRecomp bomb bomb)
200 = do { compilationProgressMsg (hsc_dflags hsc_env) $
201 ("Skipping " ++ showModMsg have_object mod_summary)
203 ; new_details <- {-# SCC "tcRnIface" #-}
204 typecheckIface hsc_env old_iface ;
205 ; dumpIfaceStats hsc_env
207 ; return (HscNoRecomp new_details old_iface)
210 ------------------------------
211 hscRecomp hsc_env msg_act mod_summary
212 have_object maybe_checked_iface
213 = case ms_hsc_src mod_summary of
215 front_res <- hscFileFrontEnd hsc_env msg_act mod_summary
216 hscBackEnd hsc_env mod_summary maybe_checked_iface front_res
219 front_res <- hscFileFrontEnd hsc_env msg_act mod_summary
220 hscBootBackEnd hsc_env mod_summary maybe_checked_iface front_res
223 front_res <- hscCoreFrontEnd hsc_env msg_act mod_summary
224 hscBackEnd hsc_env mod_summary maybe_checked_iface front_res
226 hscCoreFrontEnd hsc_env msg_act mod_summary = do {
230 ; inp <- readFile (expectJust "hscCoreFrontEnd" (ms_hspp_file mod_summary))
231 ; case parseCore inp 1 of
232 FailP s -> putMsg s{-ToDo: wrong-} >> return Nothing
233 OkP rdr_module -> do {
236 -- RENAME and TYPECHECK
238 ; (tc_msgs, maybe_tc_result) <- {-# SCC "TypeCheck" #-}
239 tcRnExtCore hsc_env rdr_module
241 ; case maybe_tc_result of
242 Nothing -> return Nothing
243 Just mod_guts -> return (Just mod_guts) -- No desugaring to do!
247 hscFileFrontEnd hsc_env msg_act mod_summary = do {
249 -- DISPLAY PROGRESS MESSAGE
251 let one_shot = isOneShot (ghcMode (hsc_dflags hsc_env))
252 ; let dflags = hsc_dflags hsc_env
253 ; let toInterp = hscTarget dflags == HscInterpreted
254 ; when (not one_shot) $
255 compilationProgressMsg dflags $
256 ("Compiling " ++ showModMsg (not toInterp) mod_summary)
261 ; let hspp_file = expectJust "hscFileFrontEnd" (ms_hspp_file mod_summary)
262 hspp_buf = ms_hspp_buf mod_summary
264 ; maybe_parsed <- myParseModule (hsc_dflags hsc_env) hspp_file hspp_buf
266 ; case maybe_parsed of {
267 Left err -> do { msg_act (unitBag err, emptyBag)
269 Right rdr_module -> do {
272 -- RENAME and TYPECHECK
274 (tc_msgs, maybe_tc_result)
275 <- {-# SCC "Typecheck-Rename" #-}
276 tcRnModule hsc_env (ms_hsc_src mod_summary) rdr_module
279 ; case maybe_tc_result of {
280 Nothing -> return Nothing ;
281 Just tc_result -> do {
286 ; (warns, maybe_ds_result) <- {-# SCC "DeSugar" #-}
287 deSugar hsc_env tc_result
288 ; msg_act (warns, emptyBag)
289 ; case maybe_ds_result of
290 Nothing -> return Nothing
291 Just ds_result -> return (Just ds_result)
294 ------------------------------
296 hscFileCheck :: HscEnv -> MessageAction -> ModSummary -> IO HscResult
297 hscFileCheck hsc_env msg_act mod_summary = do {
301 ; let hspp_file = expectJust "hscFileFrontEnd" (ms_hspp_file mod_summary)
302 hspp_buf = ms_hspp_buf mod_summary
304 ; maybe_parsed <- myParseModule (hsc_dflags hsc_env) hspp_file hspp_buf
306 ; case maybe_parsed of {
307 Left err -> do { msg_act (unitBag err, emptyBag)
309 Right rdr_module -> do {
312 -- RENAME and TYPECHECK
314 (tc_msgs, maybe_tc_result)
315 <- _scc_ "Typecheck-Rename"
316 tcRnModule hsc_env (ms_hsc_src mod_summary) rdr_module
319 ; case maybe_tc_result of {
320 Nothing -> return (HscChecked rdr_module Nothing);
321 Just tc_result -> return (HscChecked rdr_module
322 (Just (tcg_binds tc_result,
323 tcg_rdr_env tc_result)))
326 ------------------------------
327 hscBootBackEnd :: HscEnv -> ModSummary -> Maybe ModIface -> Maybe ModGuts -> IO HscResult
328 -- For hs-boot files, there's no code generation to do
330 hscBootBackEnd hsc_env mod_summary maybe_checked_iface Nothing
332 hscBootBackEnd hsc_env mod_summary maybe_checked_iface (Just ds_result)
333 = do { final_iface <- {-# SCC "MkFinalIface" #-}
334 mkIface hsc_env (ms_location mod_summary)
335 maybe_checked_iface ds_result
337 ; let { final_details = ModDetails { md_types = mg_types ds_result,
338 md_insts = mg_insts ds_result,
339 md_rules = mg_rules ds_result } }
340 -- And the answer is ...
341 ; dumpIfaceStats hsc_env
343 ; return (HscRecomp final_details
348 ------------------------------
349 hscBackEnd :: HscEnv -> ModSummary -> Maybe ModIface -> Maybe ModGuts -> IO HscResult
351 hscBackEnd hsc_env mod_summary maybe_checked_iface Nothing
354 hscBackEnd hsc_env mod_summary maybe_checked_iface (Just ds_result)
356 -- ; seqList imported_modules (return ())
358 let one_shot = isOneShot (ghcMode dflags)
359 dflags = hsc_dflags hsc_env
364 ; flat_result <- {-# SCC "Flattening" #-}
365 flatten hsc_env ds_result
368 {- TEMP: need to review space-leak fixing here
369 NB: even the code generator can force one of the
370 thunks for constructor arguments, for newtypes in particular
372 ; let -- Rule-base accumulated from imported packages
373 pkg_rule_base = eps_rule_base (hsc_EPS hsc_env)
375 -- In one-shot mode, ZAP the external package state at
376 -- this point, because we aren't going to need it from
377 -- now on. We keep the name cache, however, because
378 -- tidyCore needs it.
380 | one_shot = pcs_tc{ pcs_EPS = error "pcs_EPS missing" }
383 ; pkg_rule_base `seq` pcs_middle `seq` return ()
386 -- alive at this point:
394 ; simpl_result <- {-# SCC "Core2Core" #-}
395 core2core hsc_env flat_result
400 ; tidy_result <- {-# SCC "CoreTidy" #-}
401 tidyCorePgm hsc_env simpl_result
403 -- Emit external core
404 ; emitExternalCore dflags tidy_result
406 -- Alive at this point:
407 -- tidy_result, pcs_final
411 -- BUILD THE NEW ModIface and ModDetails
412 -- and emit external core if necessary
413 -- This has to happen *after* code gen so that the back-end
414 -- info has been set. Not yet clear if it matters waiting
415 -- until after code output
416 ; new_iface <- {-# SCC "MkFinalIface" #-}
417 mkIface hsc_env (ms_location mod_summary)
418 maybe_checked_iface tidy_result
420 -- Space leak reduction: throw away the new interface if
421 -- we're in one-shot mode; we won't be needing it any
424 if one_shot then return (error "no final iface")
425 else return new_iface
427 -- Build the final ModDetails (except in one-shot mode, where
428 -- we won't need this information after compilation).
430 if one_shot then return (error "no final details")
431 else return $! ModDetails {
432 md_types = mg_types tidy_result,
433 md_insts = mg_insts tidy_result,
434 md_rules = mg_rules tidy_result }
437 -- CONVERT TO STG and COMPLETE CODE GENERATION
438 ; (stub_h_exists, stub_c_exists, maybe_bcos)
439 <- hscCodeGen dflags tidy_result
441 -- And the answer is ...
442 ; dumpIfaceStats hsc_env
444 ; return (HscRecomp final_details
446 stub_h_exists stub_c_exists
453 ModGuts{ -- This is the last use of the ModGuts in a compilation.
454 -- From now on, we just use the bits we need.
455 mg_module = this_mod,
456 mg_binds = core_binds,
458 mg_dir_imps = dir_imps,
459 mg_foreign = foreign_stubs,
460 mg_deps = dependencies } = do {
463 -- PREPARE FOR CODE GENERATION
464 -- Do saturation and convert to A-normal form
465 prepd_binds <- {-# SCC "CorePrep" #-}
466 corePrepPgm dflags core_binds type_env;
468 case hscTarget dflags of
469 HscNothing -> return (False, False, Nothing)
473 do ----------------- Generate byte code ------------------
474 comp_bc <- byteCodeGen dflags prepd_binds type_env
476 ------------------ Create f-x-dynamic C-side stuff ---
477 (istub_h_exists, istub_c_exists)
478 <- outputForeignStubs dflags foreign_stubs
480 return ( istub_h_exists, istub_c_exists, Just comp_bc )
482 panic "GHC not compiled with interpreter"
487 ----------------- Convert to STG ------------------
488 (stg_binds, cost_centre_info) <- {-# SCC "CoreToStg" #-}
489 myCoreToStg dflags this_mod prepd_binds
491 ------------------ Code generation ------------------
492 abstractC <- {-# SCC "CodeGen" #-}
493 codeGen dflags this_mod type_env foreign_stubs
494 dir_imps cost_centre_info stg_binds
496 ------------------ Code output -----------------------
497 (stub_h_exists, stub_c_exists)
498 <- codeOutput dflags this_mod foreign_stubs
499 dependencies abstractC
501 return (stub_h_exists, stub_c_exists, Nothing)
505 hscCmmFile :: DynFlags -> FilePath -> IO Bool
506 hscCmmFile dflags filename = do
507 maybe_cmm <- parseCmmFile dflags filename
509 Nothing -> return False
511 codeOutput dflags no_mod NoStubs noDependencies [cmm]
514 no_mod = panic "hscCmmFile: no_mod"
517 myParseModule dflags src_filename maybe_src_buf
518 = -------------------------- Parser ----------------
519 showPass dflags "Parser" >>
520 {-# SCC "Parser" #-} do
522 -- sometimes we already have the buffer in memory, perhaps
523 -- because we needed to parse the imports out of it, or get the
525 buf <- case maybe_src_buf of
527 Nothing -> hGetStringBuffer src_filename
529 let loc = mkSrcLoc (mkFastString src_filename) 1 0
531 case unP parseModule (mkPState buf loc dflags) of {
533 PFailed span err -> return (Left (mkPlainErrMsg span err));
535 POk _ rdr_module -> do {
537 dumpIfSet_dyn dflags Opt_D_dump_parsed "Parser" (ppr rdr_module) ;
539 dumpIfSet_dyn dflags Opt_D_source_stats "Source Statistics"
540 (ppSourceStats False rdr_module) ;
542 return (Right rdr_module)
543 -- ToDo: free the string buffer later.
547 myCoreToStg dflags this_mod prepd_binds
549 stg_binds <- {-# SCC "Core2Stg" #-}
550 coreToStg dflags prepd_binds
552 (stg_binds2, cost_centre_info) <- {-# SCC "Core2Stg" #-}
553 stg2stg dflags this_mod stg_binds
555 return (stg_binds2, cost_centre_info)
559 %************************************************************************
561 \subsection{Compiling a do-statement}
563 %************************************************************************
565 When the UnlinkedBCOExpr is linked you get an HValue of type
567 When you run it you get a list of HValues that should be
568 the same length as the list of names; add them to the ClosureEnv.
570 A naked expression returns a singleton Name [it].
572 What you type The IO [HValue] that hscStmt returns
573 ------------- ------------------------------------
574 let pat = expr ==> let pat = expr in return [coerce HVal x, coerce HVal y, ...]
577 pat <- expr ==> expr >>= \ pat -> return [coerce HVal x, coerce HVal y, ...]
580 expr (of IO type) ==> expr >>= \ v -> return [v]
581 [NB: result not printed] bindings: [it]
584 expr (of non-IO type,
585 result showable) ==> let v = expr in print v >> return [v]
588 expr (of non-IO type,
589 result not showable) ==> error
593 hscStmt -- Compile a stmt all the way to an HValue, but don't run it
595 -> String -- The statement
596 -> IO (Maybe (HscEnv, [Name], HValue))
599 = do { maybe_stmt <- hscParseStmt (hsc_dflags hsc_env) stmt
600 ; case maybe_stmt of {
601 Nothing -> return Nothing ; -- Parse error
602 Just Nothing -> return Nothing ; -- Empty line
603 Just (Just parsed_stmt) -> do { -- The real stuff
605 -- Rename and typecheck it
606 let icontext = hsc_IC hsc_env
607 ; maybe_tc_result <- tcRnStmt hsc_env icontext parsed_stmt
609 ; case maybe_tc_result of {
610 Nothing -> return Nothing ;
611 Just (new_ic, bound_names, tc_expr) -> do {
613 -- Then desugar, code gen, and link it
614 ; hval <- compileExpr hsc_env iNTERACTIVE
615 (ic_rn_gbl_env new_ic)
619 ; return (Just (hsc_env{ hsc_IC=new_ic }, bound_names, hval))
622 hscTcExpr -- Typecheck an expression (but don't run it)
624 -> String -- The expression
627 hscTcExpr hsc_env expr
628 = do { maybe_stmt <- hscParseStmt (hsc_dflags hsc_env) expr
629 ; let icontext = hsc_IC hsc_env
630 ; case maybe_stmt of {
631 Nothing -> return Nothing ; -- Parse error
632 Just (Just (L _ (ExprStmt expr _ _)))
633 -> tcRnExpr hsc_env icontext expr ;
634 Just other -> do { errorMsg ("not an expression: `" ++ expr ++ "'") ;
638 hscKcType -- Find the kind of a type
640 -> String -- The type
643 hscKcType hsc_env str
644 = do { maybe_type <- hscParseType (hsc_dflags hsc_env) str
645 ; let icontext = hsc_IC hsc_env
646 ; case maybe_type of {
647 Just ty -> tcRnType hsc_env icontext ty ;
648 Just other -> do { errorMsg ("not an type: `" ++ str ++ "'") ;
650 Nothing -> return Nothing } }
655 hscParseStmt :: DynFlags -> String -> IO (Maybe (Maybe (LStmt RdrName)))
656 hscParseStmt = hscParseThing parseStmt
658 hscParseType :: DynFlags -> String -> IO (Maybe (LHsType RdrName))
659 hscParseType = hscParseThing parseType
661 hscParseIdentifier :: DynFlags -> String -> IO (Maybe (Located RdrName))
662 hscParseIdentifier = hscParseThing parseIdentifier
664 hscParseThing :: Outputable thing
666 -> DynFlags -> String
668 -- Nothing => Parse error (message already printed)
670 hscParseThing parser dflags str
671 = showPass dflags "Parser" >>
672 {-# SCC "Parser" #-} do
674 buf <- stringToStringBuffer str
676 let loc = mkSrcLoc FSLIT("<interactive>") 1 0
678 case unP parser (mkPState buf loc dflags) of {
680 PFailed span err -> do { printError span err;
685 --ToDo: can't free the string buffer until we've finished this
686 -- compilation sweep and all the identifiers have gone away.
687 dumpIfSet_dyn dflags Opt_D_dump_parsed "Parser" (ppr thing);
692 %************************************************************************
694 \subsection{Getting information about an identifer}
696 %************************************************************************
700 hscGetInfo -- like hscStmt, but deals with a single identifier
702 -> String -- The identifier
703 -> IO [GetInfoResult]
705 hscGetInfo hsc_env str
706 = do maybe_rdr_name <- hscParseIdentifier (hsc_dflags hsc_env) str
707 case maybe_rdr_name of {
708 Nothing -> return [];
709 Just (L _ rdr_name) -> do
711 maybe_tc_result <- tcRnGetInfo hsc_env (hsc_IC hsc_env) rdr_name
713 case maybe_tc_result of
715 Just things -> return things
720 %************************************************************************
722 Desugar, simplify, convert to bytecode, and link an expression
724 %************************************************************************
728 compileExpr :: HscEnv
729 -> Module -> GlobalRdrEnv -> TypeEnv
733 compileExpr hsc_env this_mod rdr_env type_env tc_expr
734 = do { let { dflags = hsc_dflags hsc_env ;
735 lint_on = dopt Opt_DoCoreLinting dflags }
738 ; ds_expr <- deSugarExpr hsc_env this_mod rdr_env type_env tc_expr
741 ; flat_expr <- flattenExpr hsc_env ds_expr
744 ; simpl_expr <- simplifyExpr dflags flat_expr
746 -- Tidy it (temporary, until coreSat does cloning)
747 ; tidy_expr <- tidyCoreExpr simpl_expr
749 -- Prepare for codegen
750 ; prepd_expr <- corePrepExpr dflags tidy_expr
753 -- ToDo: improve SrcLoc
755 case lintUnfolding noSrcLoc [] prepd_expr of
756 Just err -> pprPanic "compileExpr" err
762 ; bcos <- coreExprToBCOs dflags prepd_expr
765 ; hval <- linkExpr hsc_env bcos
773 %************************************************************************
775 Statistics on reading interfaces
777 %************************************************************************
780 dumpIfaceStats :: HscEnv -> IO ()
781 dumpIfaceStats hsc_env
782 = do { eps <- readIORef (hsc_EPS hsc_env)
783 ; dumpIfSet (dump_if_trace || dump_rn_stats)
784 "Interface statistics"
787 dflags = hsc_dflags hsc_env
788 dump_rn_stats = dopt Opt_D_dump_rn_stats dflags
789 dump_if_trace = dopt Opt_D_dump_if_trace dflags