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
141 (Located (HsModule RdrName))
142 (Maybe (LHsBinds Id, GlobalRdrEnv, ModDetails))
144 -- Concluded that it wasn't necessary
145 | HscNoRecomp ModDetails -- new details (HomeSymbolTable additions)
146 ModIface -- new iface (if any compilation was done)
149 | HscRecomp ModDetails -- new details (HomeSymbolTable additions)
150 ModIface -- new iface (if any compilation was done)
151 Bool -- stub_h exists
152 Bool -- stub_c exists
153 (Maybe CompiledByteCode)
156 -- What to do when we have compiler error or warning messages
157 type MessageAction = Messages -> IO ()
159 -- no errors or warnings; the individual passes
160 -- (parse/rename/typecheck) print messages themselves
164 -> MessageAction -- What to do with errors/warnings
166 -> Bool -- True <=> source unchanged
167 -> Bool -- True <=> have an object file (for msgs only)
168 -> Maybe ModIface -- Old interface, if available
169 -> Maybe (Int, Int) -- Just (i,n) <=> module i of n (for msgs)
172 hscMain hsc_env msg_act mod_summary
173 source_unchanged have_object maybe_old_iface
176 (recomp_reqd, maybe_checked_iface) <-
177 {-# SCC "checkOldIface" #-}
178 checkOldIface hsc_env mod_summary
179 source_unchanged maybe_old_iface;
181 let no_old_iface = not (isJust maybe_checked_iface)
182 what_next | recomp_reqd || no_old_iface = hscRecomp
183 | otherwise = hscNoRecomp
185 ; what_next hsc_env msg_act mod_summary have_object
191 ------------------------------
192 -- hscNoRecomp definitely expects to have the old interface available
193 hscNoRecomp hsc_env msg_act mod_summary
194 have_object (Just old_iface)
196 | isOneShot (ghcMode (hsc_dflags hsc_env))
198 compilationProgressMsg (hsc_dflags hsc_env) $
199 "compilation IS NOT required";
200 dumpIfaceStats hsc_env ;
202 let { bomb = panic "hscNoRecomp:OneShot" };
203 return (HscNoRecomp bomb bomb)
206 = do { compilationProgressMsg (hsc_dflags hsc_env) $
207 (showModuleIndex mb_mod_index ++
208 "Skipping " ++ showModMsg have_object mod_summary)
210 ; new_details <- {-# SCC "tcRnIface" #-}
211 typecheckIface hsc_env old_iface ;
212 ; dumpIfaceStats hsc_env
214 ; return (HscNoRecomp new_details old_iface)
217 ------------------------------
218 hscRecomp hsc_env msg_act mod_summary
219 have_object maybe_checked_iface
221 = case ms_hsc_src mod_summary of
223 front_res <- hscFileFrontEnd hsc_env msg_act mod_summary mb_mod_index
224 hscBackEnd hsc_env mod_summary maybe_checked_iface front_res
227 front_res <- hscFileFrontEnd hsc_env msg_act mod_summary mb_mod_index
228 hscBootBackEnd hsc_env mod_summary maybe_checked_iface front_res
231 front_res <- hscCoreFrontEnd hsc_env msg_act mod_summary
232 hscBackEnd hsc_env mod_summary maybe_checked_iface front_res
234 hscCoreFrontEnd hsc_env msg_act mod_summary = do {
238 ; inp <- readFile (expectJust "hscCoreFrontEnd" (ms_hspp_file mod_summary))
239 ; case parseCore inp 1 of
240 FailP s -> putMsg s{-ToDo: wrong-} >> return Nothing
241 OkP rdr_module -> do {
244 -- RENAME and TYPECHECK
246 ; (tc_msgs, maybe_tc_result) <- {-# SCC "TypeCheck" #-}
247 tcRnExtCore hsc_env rdr_module
249 ; case maybe_tc_result of
250 Nothing -> return Nothing
251 Just mod_guts -> return (Just mod_guts) -- No desugaring to do!
255 hscFileFrontEnd hsc_env msg_act mod_summary mb_mod_index = do {
257 -- DISPLAY PROGRESS MESSAGE
259 let one_shot = isOneShot (ghcMode (hsc_dflags hsc_env))
260 ; let dflags = hsc_dflags hsc_env
261 ; let toInterp = hscTarget dflags == HscInterpreted
262 ; when (not one_shot) $
263 compilationProgressMsg dflags $
264 (showModuleIndex mb_mod_index ++
265 "Compiling " ++ showModMsg (not toInterp) mod_summary)
270 ; let hspp_file = expectJust "hscFileFrontEnd" (ms_hspp_file mod_summary)
271 hspp_buf = ms_hspp_buf mod_summary
273 ; maybe_parsed <- myParseModule (hsc_dflags hsc_env) hspp_file hspp_buf
275 ; case maybe_parsed of {
276 Left err -> do { msg_act (unitBag err, emptyBag)
278 Right rdr_module -> do {
281 -- RENAME and TYPECHECK
283 (tc_msgs, maybe_tc_result)
284 <- {-# SCC "Typecheck-Rename" #-}
285 tcRnModule hsc_env (ms_hsc_src mod_summary) rdr_module
288 ; case maybe_tc_result of {
289 Nothing -> return Nothing ;
290 Just tc_result -> do {
295 ; (warns, maybe_ds_result) <- {-# SCC "DeSugar" #-}
296 deSugar hsc_env tc_result
297 ; msg_act (warns, emptyBag)
298 ; case maybe_ds_result of
299 Nothing -> return Nothing
300 Just ds_result -> return (Just ds_result)
303 ------------------------------
305 hscFileCheck :: HscEnv -> MessageAction -> ModSummary -> IO HscResult
306 hscFileCheck hsc_env msg_act mod_summary = do {
310 ; let hspp_file = expectJust "hscFileFrontEnd" (ms_hspp_file mod_summary)
311 hspp_buf = ms_hspp_buf mod_summary
313 ; maybe_parsed <- myParseModule (hsc_dflags hsc_env) hspp_file hspp_buf
315 ; case maybe_parsed of {
316 Left err -> do { msg_act (unitBag err, emptyBag)
318 Right rdr_module -> do {
321 -- RENAME and TYPECHECK
323 (tc_msgs, maybe_tc_result)
324 <- _scc_ "Typecheck-Rename"
325 tcRnModule hsc_env (ms_hsc_src mod_summary) rdr_module
328 ; case maybe_tc_result of {
329 Nothing -> return (HscChecked rdr_module Nothing);
331 let md = ModDetails {
332 md_types = tcg_type_env tc_result,
333 md_exports = tcg_exports tc_result,
334 md_insts = tcg_insts tc_result,
335 md_rules = [panic "no rules"] }
336 -- rules are IdCoreRules, not the
337 -- RuleDecls we get out of the typechecker
338 return (HscChecked rdr_module
339 (Just (tcg_binds tc_result,
340 tcg_rdr_env tc_result,
344 ------------------------------
345 hscBootBackEnd :: HscEnv -> ModSummary -> Maybe ModIface -> Maybe ModGuts -> IO HscResult
346 -- For hs-boot files, there's no code generation to do
348 hscBootBackEnd hsc_env mod_summary maybe_checked_iface Nothing
350 hscBootBackEnd hsc_env mod_summary maybe_checked_iface (Just ds_result)
351 = do { final_iface <- {-# SCC "MkFinalIface" #-}
352 mkIface hsc_env (ms_location mod_summary)
353 maybe_checked_iface ds_result
355 ; let { final_details = ModDetails { md_types = mg_types ds_result,
356 md_exports = mg_exports ds_result,
357 md_insts = mg_insts ds_result,
358 md_rules = mg_rules ds_result } }
359 -- And the answer is ...
360 ; dumpIfaceStats hsc_env
362 ; return (HscRecomp final_details
367 ------------------------------
368 hscBackEnd :: HscEnv -> ModSummary -> Maybe ModIface -> Maybe ModGuts -> IO HscResult
370 hscBackEnd hsc_env mod_summary maybe_checked_iface Nothing
373 hscBackEnd hsc_env mod_summary maybe_checked_iface (Just ds_result)
375 -- ; seqList imported_modules (return ())
377 let one_shot = isOneShot (ghcMode dflags)
378 dflags = hsc_dflags hsc_env
383 ; flat_result <- {-# SCC "Flattening" #-}
384 flatten hsc_env ds_result
387 {- TEMP: need to review space-leak fixing here
388 NB: even the code generator can force one of the
389 thunks for constructor arguments, for newtypes in particular
391 ; let -- Rule-base accumulated from imported packages
392 pkg_rule_base = eps_rule_base (hsc_EPS hsc_env)
394 -- In one-shot mode, ZAP the external package state at
395 -- this point, because we aren't going to need it from
396 -- now on. We keep the name cache, however, because
397 -- tidyCore needs it.
399 | one_shot = pcs_tc{ pcs_EPS = error "pcs_EPS missing" }
402 ; pkg_rule_base `seq` pcs_middle `seq` return ()
405 -- alive at this point:
413 ; simpl_result <- {-# SCC "Core2Core" #-}
414 core2core hsc_env flat_result
419 ; tidy_result <- {-# SCC "CoreTidy" #-}
420 tidyCorePgm hsc_env simpl_result
422 -- Emit external core
423 ; emitExternalCore dflags tidy_result
425 -- Alive at this point:
426 -- tidy_result, pcs_final
430 -- BUILD THE NEW ModIface and ModDetails
431 -- and emit external core if necessary
432 -- This has to happen *after* code gen so that the back-end
433 -- info has been set. Not yet clear if it matters waiting
434 -- until after code output
435 ; new_iface <- {-# SCC "MkFinalIface" #-}
436 mkIface hsc_env (ms_location mod_summary)
437 maybe_checked_iface tidy_result
439 -- Space leak reduction: throw away the new interface if
440 -- we're in one-shot mode; we won't be needing it any
443 if one_shot then return (error "no final iface")
444 else return new_iface
446 -- Build the final ModDetails (except in one-shot mode, where
447 -- we won't need this information after compilation).
449 if one_shot then return (error "no final details")
450 else return $! ModDetails {
451 md_types = mg_types tidy_result,
452 md_exports = mg_exports tidy_result,
453 md_insts = mg_insts tidy_result,
454 md_rules = mg_rules tidy_result }
457 -- CONVERT TO STG and COMPLETE CODE GENERATION
458 ; (stub_h_exists, stub_c_exists, maybe_bcos)
459 <- hscCodeGen dflags tidy_result
461 -- And the answer is ...
462 ; dumpIfaceStats hsc_env
464 ; return (HscRecomp final_details
466 stub_h_exists stub_c_exists
473 ModGuts{ -- This is the last use of the ModGuts in a compilation.
474 -- From now on, we just use the bits we need.
475 mg_module = this_mod,
476 mg_binds = core_binds,
478 mg_dir_imps = dir_imps,
479 mg_foreign = foreign_stubs,
480 mg_deps = dependencies } = do {
483 -- PREPARE FOR CODE GENERATION
484 -- Do saturation and convert to A-normal form
485 prepd_binds <- {-# SCC "CorePrep" #-}
486 corePrepPgm dflags core_binds type_env;
488 case hscTarget dflags of
489 HscNothing -> return (False, False, Nothing)
493 do ----------------- Generate byte code ------------------
494 comp_bc <- byteCodeGen dflags prepd_binds type_env
496 ------------------ Create f-x-dynamic C-side stuff ---
497 (istub_h_exists, istub_c_exists)
498 <- outputForeignStubs dflags foreign_stubs
500 return ( istub_h_exists, istub_c_exists, Just comp_bc )
502 panic "GHC not compiled with interpreter"
507 ----------------- Convert to STG ------------------
508 (stg_binds, cost_centre_info) <- {-# SCC "CoreToStg" #-}
509 myCoreToStg dflags this_mod prepd_binds
511 ------------------ Code generation ------------------
512 abstractC <- {-# SCC "CodeGen" #-}
513 codeGen dflags this_mod type_env foreign_stubs
514 dir_imps cost_centre_info stg_binds
516 ------------------ Code output -----------------------
517 (stub_h_exists, stub_c_exists)
518 <- codeOutput dflags this_mod foreign_stubs
519 dependencies abstractC
521 return (stub_h_exists, stub_c_exists, Nothing)
525 hscCmmFile :: DynFlags -> FilePath -> IO Bool
526 hscCmmFile dflags filename = do
527 maybe_cmm <- parseCmmFile dflags filename
529 Nothing -> return False
531 codeOutput dflags no_mod NoStubs noDependencies [cmm]
534 no_mod = panic "hscCmmFile: no_mod"
537 myParseModule dflags src_filename maybe_src_buf
538 = -------------------------- Parser ----------------
539 showPass dflags "Parser" >>
540 {-# SCC "Parser" #-} do
542 -- sometimes we already have the buffer in memory, perhaps
543 -- because we needed to parse the imports out of it, or get the
545 buf <- case maybe_src_buf of
547 Nothing -> hGetStringBuffer src_filename
549 let loc = mkSrcLoc (mkFastString src_filename) 1 0
551 case unP parseModule (mkPState buf loc dflags) of {
553 PFailed span err -> return (Left (mkPlainErrMsg span err));
555 POk _ rdr_module -> do {
557 dumpIfSet_dyn dflags Opt_D_dump_parsed "Parser" (ppr rdr_module) ;
559 dumpIfSet_dyn dflags Opt_D_source_stats "Source Statistics"
560 (ppSourceStats False rdr_module) ;
562 return (Right rdr_module)
563 -- ToDo: free the string buffer later.
567 myCoreToStg dflags this_mod prepd_binds
569 stg_binds <- {-# SCC "Core2Stg" #-}
570 coreToStg dflags prepd_binds
572 (stg_binds2, cost_centre_info) <- {-# SCC "Core2Stg" #-}
573 stg2stg dflags this_mod stg_binds
575 return (stg_binds2, cost_centre_info)
579 %************************************************************************
581 \subsection{Compiling a do-statement}
583 %************************************************************************
585 When the UnlinkedBCOExpr is linked you get an HValue of type
587 When you run it you get a list of HValues that should be
588 the same length as the list of names; add them to the ClosureEnv.
590 A naked expression returns a singleton Name [it].
592 What you type The IO [HValue] that hscStmt returns
593 ------------- ------------------------------------
594 let pat = expr ==> let pat = expr in return [coerce HVal x, coerce HVal y, ...]
597 pat <- expr ==> expr >>= \ pat -> return [coerce HVal x, coerce HVal y, ...]
600 expr (of IO type) ==> expr >>= \ v -> return [v]
601 [NB: result not printed] bindings: [it]
604 expr (of non-IO type,
605 result showable) ==> let v = expr in print v >> return [v]
608 expr (of non-IO type,
609 result not showable) ==> error
613 hscStmt -- Compile a stmt all the way to an HValue, but don't run it
615 -> String -- The statement
616 -> IO (Maybe (HscEnv, [Name], HValue))
619 = do { maybe_stmt <- hscParseStmt (hsc_dflags hsc_env) stmt
620 ; case maybe_stmt of {
621 Nothing -> return Nothing ; -- Parse error
622 Just Nothing -> return Nothing ; -- Empty line
623 Just (Just parsed_stmt) -> do { -- The real stuff
625 -- Rename and typecheck it
626 let icontext = hsc_IC hsc_env
627 ; maybe_tc_result <- tcRnStmt hsc_env icontext parsed_stmt
629 ; case maybe_tc_result of {
630 Nothing -> return Nothing ;
631 Just (new_ic, bound_names, tc_expr) -> do {
633 -- Then desugar, code gen, and link it
634 ; hval <- compileExpr hsc_env iNTERACTIVE
635 (ic_rn_gbl_env new_ic)
639 ; return (Just (hsc_env{ hsc_IC=new_ic }, bound_names, hval))
642 hscTcExpr -- Typecheck an expression (but don't run it)
644 -> String -- The expression
647 hscTcExpr hsc_env expr
648 = do { maybe_stmt <- hscParseStmt (hsc_dflags hsc_env) expr
649 ; let icontext = hsc_IC hsc_env
650 ; case maybe_stmt of {
651 Nothing -> return Nothing ; -- Parse error
652 Just (Just (L _ (ExprStmt expr _ _)))
653 -> tcRnExpr hsc_env icontext expr ;
654 Just other -> do { errorMsg ("not an expression: `" ++ expr ++ "'") ;
658 hscKcType -- Find the kind of a type
660 -> String -- The type
663 hscKcType hsc_env str
664 = do { maybe_type <- hscParseType (hsc_dflags hsc_env) str
665 ; let icontext = hsc_IC hsc_env
666 ; case maybe_type of {
667 Just ty -> tcRnType hsc_env icontext ty ;
668 Just other -> do { errorMsg ("not an type: `" ++ str ++ "'") ;
670 Nothing -> return Nothing } }
675 hscParseStmt :: DynFlags -> String -> IO (Maybe (Maybe (LStmt RdrName)))
676 hscParseStmt = hscParseThing parseStmt
678 hscParseType :: DynFlags -> String -> IO (Maybe (LHsType RdrName))
679 hscParseType = hscParseThing parseType
681 hscParseIdentifier :: DynFlags -> String -> IO (Maybe (Located RdrName))
682 hscParseIdentifier = hscParseThing parseIdentifier
684 hscParseThing :: Outputable thing
686 -> DynFlags -> String
688 -- Nothing => Parse error (message already printed)
690 hscParseThing parser dflags str
691 = showPass dflags "Parser" >>
692 {-# SCC "Parser" #-} do
694 buf <- stringToStringBuffer str
696 let loc = mkSrcLoc FSLIT("<interactive>") 1 0
698 case unP parser (mkPState buf loc dflags) of {
700 PFailed span err -> do { printError span err;
705 --ToDo: can't free the string buffer until we've finished this
706 -- compilation sweep and all the identifiers have gone away.
707 dumpIfSet_dyn dflags Opt_D_dump_parsed "Parser" (ppr thing);
712 %************************************************************************
714 \subsection{Getting information about an identifer}
716 %************************************************************************
720 hscGetInfo -- like hscStmt, but deals with a single identifier
722 -> String -- The identifier
723 -> IO [GetInfoResult]
725 hscGetInfo hsc_env str
726 = do maybe_rdr_name <- hscParseIdentifier (hsc_dflags hsc_env) str
727 case maybe_rdr_name of {
728 Nothing -> return [];
729 Just (L _ rdr_name) -> do
731 maybe_tc_result <- tcRnGetInfo hsc_env (hsc_IC hsc_env) rdr_name
733 case maybe_tc_result of
735 Just things -> return things
740 %************************************************************************
742 Desugar, simplify, convert to bytecode, and link an expression
744 %************************************************************************
748 compileExpr :: HscEnv
749 -> Module -> GlobalRdrEnv -> TypeEnv
753 compileExpr hsc_env this_mod rdr_env type_env tc_expr
754 = do { let { dflags = hsc_dflags hsc_env ;
755 lint_on = dopt Opt_DoCoreLinting dflags }
758 ; ds_expr <- deSugarExpr hsc_env this_mod rdr_env type_env tc_expr
761 ; flat_expr <- flattenExpr hsc_env ds_expr
764 ; simpl_expr <- simplifyExpr dflags flat_expr
766 -- Tidy it (temporary, until coreSat does cloning)
767 ; tidy_expr <- tidyCoreExpr simpl_expr
769 -- Prepare for codegen
770 ; prepd_expr <- corePrepExpr dflags tidy_expr
773 -- ToDo: improve SrcLoc
775 case lintUnfolding noSrcLoc [] prepd_expr of
776 Just err -> pprPanic "compileExpr" err
782 ; bcos <- coreExprToBCOs dflags prepd_expr
785 ; hval <- linkExpr hsc_env bcos
793 %************************************************************************
795 Statistics on reading interfaces
797 %************************************************************************
800 dumpIfaceStats :: HscEnv -> IO ()
801 dumpIfaceStats hsc_env
802 = do { eps <- readIORef (hsc_EPS hsc_env)
803 ; dumpIfSet (dump_if_trace || dump_rn_stats)
804 "Interface statistics"
807 dflags = hsc_dflags hsc_env
808 dump_rn_stats = dopt Opt_D_dump_rn_stats dflags
809 dump_if_trace = dopt Opt_D_dump_if_trace dflags
812 %************************************************************************
814 Progress Messages: Module i of n
816 %************************************************************************
819 showModuleIndex Nothing = ""
820 showModuleIndex (Just (i,n)) = "[" ++ padded ++ " of " ++ n_str ++ "] "
824 padded = replicate (length n_str - length i_str) ' ' ++ i_str