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
171 hscMain hsc_env msg_act mod_summary
172 source_unchanged have_object maybe_old_iface
174 (recomp_reqd, maybe_checked_iface) <-
175 {-# SCC "checkOldIface" #-}
176 checkOldIface hsc_env mod_summary
177 source_unchanged maybe_old_iface;
179 let no_old_iface = not (isJust maybe_checked_iface)
180 what_next | recomp_reqd || no_old_iface = hscRecomp
181 | otherwise = hscNoRecomp
183 ; what_next hsc_env msg_act mod_summary have_object
188 ------------------------------
189 -- hscNoRecomp definitely expects to have the old interface available
190 hscNoRecomp hsc_env msg_act mod_summary
191 have_object (Just old_iface)
192 | isOneShot (ghcMode (hsc_dflags hsc_env))
194 compilationProgressMsg (hsc_dflags hsc_env) $
195 "compilation IS NOT required";
196 dumpIfaceStats hsc_env ;
198 let { bomb = panic "hscNoRecomp:OneShot" };
199 return (HscNoRecomp bomb bomb)
202 = do { compilationProgressMsg (hsc_dflags hsc_env) $
203 ("Skipping " ++ showModMsg have_object mod_summary)
205 ; new_details <- {-# SCC "tcRnIface" #-}
206 typecheckIface hsc_env old_iface ;
207 ; dumpIfaceStats hsc_env
209 ; return (HscNoRecomp new_details old_iface)
212 ------------------------------
213 hscRecomp hsc_env msg_act mod_summary
214 have_object maybe_checked_iface
215 = case ms_hsc_src mod_summary of
217 front_res <- hscFileFrontEnd hsc_env msg_act mod_summary
218 hscBackEnd hsc_env mod_summary maybe_checked_iface front_res
221 front_res <- hscFileFrontEnd hsc_env msg_act mod_summary
222 hscBootBackEnd hsc_env mod_summary maybe_checked_iface front_res
225 front_res <- hscCoreFrontEnd hsc_env msg_act mod_summary
226 hscBackEnd hsc_env mod_summary maybe_checked_iface front_res
228 hscCoreFrontEnd hsc_env msg_act mod_summary = do {
232 ; inp <- readFile (expectJust "hscCoreFrontEnd" (ms_hspp_file mod_summary))
233 ; case parseCore inp 1 of
234 FailP s -> putMsg s{-ToDo: wrong-} >> return Nothing
235 OkP rdr_module -> do {
238 -- RENAME and TYPECHECK
240 ; (tc_msgs, maybe_tc_result) <- {-# SCC "TypeCheck" #-}
241 tcRnExtCore hsc_env rdr_module
243 ; case maybe_tc_result of
244 Nothing -> return Nothing
245 Just mod_guts -> return (Just mod_guts) -- No desugaring to do!
249 hscFileFrontEnd hsc_env msg_act mod_summary = do {
251 -- DISPLAY PROGRESS MESSAGE
253 let one_shot = isOneShot (ghcMode (hsc_dflags hsc_env))
254 ; let dflags = hsc_dflags hsc_env
255 ; let toInterp = hscTarget dflags == HscInterpreted
256 ; when (not one_shot) $
257 compilationProgressMsg dflags $
258 ("Compiling " ++ showModMsg (not toInterp) mod_summary)
263 ; let hspp_file = expectJust "hscFileFrontEnd" (ms_hspp_file mod_summary)
264 hspp_buf = ms_hspp_buf mod_summary
266 ; maybe_parsed <- myParseModule (hsc_dflags hsc_env) hspp_file hspp_buf
268 ; case maybe_parsed of {
269 Left err -> do { msg_act (unitBag err, emptyBag)
271 Right rdr_module -> do {
274 -- RENAME and TYPECHECK
276 (tc_msgs, maybe_tc_result)
277 <- {-# SCC "Typecheck-Rename" #-}
278 tcRnModule hsc_env (ms_hsc_src mod_summary) rdr_module
281 ; case maybe_tc_result of {
282 Nothing -> return Nothing ;
283 Just tc_result -> do {
288 ; (warns, maybe_ds_result) <- {-# SCC "DeSugar" #-}
289 deSugar hsc_env tc_result
290 ; msg_act (warns, emptyBag)
291 ; case maybe_ds_result of
292 Nothing -> return Nothing
293 Just ds_result -> return (Just ds_result)
296 ------------------------------
298 hscFileCheck :: HscEnv -> MessageAction -> ModSummary -> IO HscResult
299 hscFileCheck hsc_env msg_act mod_summary = do {
303 ; let hspp_file = expectJust "hscFileFrontEnd" (ms_hspp_file mod_summary)
304 hspp_buf = ms_hspp_buf mod_summary
306 ; maybe_parsed <- myParseModule (hsc_dflags hsc_env) hspp_file hspp_buf
308 ; case maybe_parsed of {
309 Left err -> do { msg_act (unitBag err, emptyBag)
311 Right rdr_module -> do {
314 -- RENAME and TYPECHECK
316 (tc_msgs, maybe_tc_result)
317 <- _scc_ "Typecheck-Rename"
318 tcRnModule hsc_env (ms_hsc_src mod_summary) rdr_module
321 ; case maybe_tc_result of {
322 Nothing -> return (HscChecked rdr_module Nothing);
324 let md = ModDetails {
325 md_types = tcg_type_env tc_result,
326 md_exports = tcg_exports tc_result,
327 md_insts = tcg_insts tc_result,
328 md_rules = [panic "no rules"] }
329 -- rules are IdCoreRules, not the
330 -- RuleDecls we get out of the typechecker
331 return (HscChecked rdr_module
332 (Just (tcg_binds tc_result,
333 tcg_rdr_env tc_result,
337 ------------------------------
338 hscBootBackEnd :: HscEnv -> ModSummary -> Maybe ModIface -> Maybe ModGuts -> IO HscResult
339 -- For hs-boot files, there's no code generation to do
341 hscBootBackEnd hsc_env mod_summary maybe_checked_iface Nothing
343 hscBootBackEnd hsc_env mod_summary maybe_checked_iface (Just ds_result)
344 = do { final_iface <- {-# SCC "MkFinalIface" #-}
345 mkIface hsc_env (ms_location mod_summary)
346 maybe_checked_iface ds_result
348 ; let { final_details = ModDetails { md_types = mg_types ds_result,
349 md_exports = mg_exports ds_result,
350 md_insts = mg_insts ds_result,
351 md_rules = mg_rules ds_result } }
352 -- And the answer is ...
353 ; dumpIfaceStats hsc_env
355 ; return (HscRecomp final_details
360 ------------------------------
361 hscBackEnd :: HscEnv -> ModSummary -> Maybe ModIface -> Maybe ModGuts -> IO HscResult
363 hscBackEnd hsc_env mod_summary maybe_checked_iface Nothing
366 hscBackEnd hsc_env mod_summary maybe_checked_iface (Just ds_result)
368 -- ; seqList imported_modules (return ())
370 let one_shot = isOneShot (ghcMode dflags)
371 dflags = hsc_dflags hsc_env
376 ; flat_result <- {-# SCC "Flattening" #-}
377 flatten hsc_env ds_result
380 {- TEMP: need to review space-leak fixing here
381 NB: even the code generator can force one of the
382 thunks for constructor arguments, for newtypes in particular
384 ; let -- Rule-base accumulated from imported packages
385 pkg_rule_base = eps_rule_base (hsc_EPS hsc_env)
387 -- In one-shot mode, ZAP the external package state at
388 -- this point, because we aren't going to need it from
389 -- now on. We keep the name cache, however, because
390 -- tidyCore needs it.
392 | one_shot = pcs_tc{ pcs_EPS = error "pcs_EPS missing" }
395 ; pkg_rule_base `seq` pcs_middle `seq` return ()
398 -- alive at this point:
406 ; simpl_result <- {-# SCC "Core2Core" #-}
407 core2core hsc_env flat_result
412 ; tidy_result <- {-# SCC "CoreTidy" #-}
413 tidyCorePgm hsc_env simpl_result
415 -- Emit external core
416 ; emitExternalCore dflags tidy_result
418 -- Alive at this point:
419 -- tidy_result, pcs_final
423 -- BUILD THE NEW ModIface and ModDetails
424 -- and emit external core if necessary
425 -- This has to happen *after* code gen so that the back-end
426 -- info has been set. Not yet clear if it matters waiting
427 -- until after code output
428 ; new_iface <- {-# SCC "MkFinalIface" #-}
429 mkIface hsc_env (ms_location mod_summary)
430 maybe_checked_iface tidy_result
432 -- Space leak reduction: throw away the new interface if
433 -- we're in one-shot mode; we won't be needing it any
436 if one_shot then return (error "no final iface")
437 else return new_iface
439 -- Build the final ModDetails (except in one-shot mode, where
440 -- we won't need this information after compilation).
442 if one_shot then return (error "no final details")
443 else return $! ModDetails {
444 md_types = mg_types tidy_result,
445 md_exports = mg_exports tidy_result,
446 md_insts = mg_insts tidy_result,
447 md_rules = mg_rules tidy_result }
450 -- CONVERT TO STG and COMPLETE CODE GENERATION
451 ; (stub_h_exists, stub_c_exists, maybe_bcos)
452 <- hscCodeGen dflags tidy_result
454 -- And the answer is ...
455 ; dumpIfaceStats hsc_env
457 ; return (HscRecomp final_details
459 stub_h_exists stub_c_exists
466 ModGuts{ -- This is the last use of the ModGuts in a compilation.
467 -- From now on, we just use the bits we need.
468 mg_module = this_mod,
469 mg_binds = core_binds,
471 mg_dir_imps = dir_imps,
472 mg_foreign = foreign_stubs,
473 mg_deps = dependencies } = do {
476 -- PREPARE FOR CODE GENERATION
477 -- Do saturation and convert to A-normal form
478 prepd_binds <- {-# SCC "CorePrep" #-}
479 corePrepPgm dflags core_binds type_env;
481 case hscTarget dflags of
482 HscNothing -> return (False, False, Nothing)
486 do ----------------- Generate byte code ------------------
487 comp_bc <- byteCodeGen dflags prepd_binds type_env
489 ------------------ Create f-x-dynamic C-side stuff ---
490 (istub_h_exists, istub_c_exists)
491 <- outputForeignStubs dflags foreign_stubs
493 return ( istub_h_exists, istub_c_exists, Just comp_bc )
495 panic "GHC not compiled with interpreter"
500 ----------------- Convert to STG ------------------
501 (stg_binds, cost_centre_info) <- {-# SCC "CoreToStg" #-}
502 myCoreToStg dflags this_mod prepd_binds
504 ------------------ Code generation ------------------
505 abstractC <- {-# SCC "CodeGen" #-}
506 codeGen dflags this_mod type_env foreign_stubs
507 dir_imps cost_centre_info stg_binds
509 ------------------ Code output -----------------------
510 (stub_h_exists, stub_c_exists)
511 <- codeOutput dflags this_mod foreign_stubs
512 dependencies abstractC
514 return (stub_h_exists, stub_c_exists, Nothing)
518 hscCmmFile :: DynFlags -> FilePath -> IO Bool
519 hscCmmFile dflags filename = do
520 maybe_cmm <- parseCmmFile dflags filename
522 Nothing -> return False
524 codeOutput dflags no_mod NoStubs noDependencies [cmm]
527 no_mod = panic "hscCmmFile: no_mod"
530 myParseModule dflags src_filename maybe_src_buf
531 = -------------------------- Parser ----------------
532 showPass dflags "Parser" >>
533 {-# SCC "Parser" #-} do
535 -- sometimes we already have the buffer in memory, perhaps
536 -- because we needed to parse the imports out of it, or get the
538 buf <- case maybe_src_buf of
540 Nothing -> hGetStringBuffer src_filename
542 let loc = mkSrcLoc (mkFastString src_filename) 1 0
544 case unP parseModule (mkPState buf loc dflags) of {
546 PFailed span err -> return (Left (mkPlainErrMsg span err));
548 POk _ rdr_module -> do {
550 dumpIfSet_dyn dflags Opt_D_dump_parsed "Parser" (ppr rdr_module) ;
552 dumpIfSet_dyn dflags Opt_D_source_stats "Source Statistics"
553 (ppSourceStats False rdr_module) ;
555 return (Right rdr_module)
556 -- ToDo: free the string buffer later.
560 myCoreToStg dflags this_mod prepd_binds
562 stg_binds <- {-# SCC "Core2Stg" #-}
563 coreToStg dflags prepd_binds
565 (stg_binds2, cost_centre_info) <- {-# SCC "Core2Stg" #-}
566 stg2stg dflags this_mod stg_binds
568 return (stg_binds2, cost_centre_info)
572 %************************************************************************
574 \subsection{Compiling a do-statement}
576 %************************************************************************
578 When the UnlinkedBCOExpr is linked you get an HValue of type
580 When you run it you get a list of HValues that should be
581 the same length as the list of names; add them to the ClosureEnv.
583 A naked expression returns a singleton Name [it].
585 What you type The IO [HValue] that hscStmt returns
586 ------------- ------------------------------------
587 let pat = expr ==> let pat = expr in return [coerce HVal x, coerce HVal y, ...]
590 pat <- expr ==> expr >>= \ pat -> return [coerce HVal x, coerce HVal y, ...]
593 expr (of IO type) ==> expr >>= \ v -> return [v]
594 [NB: result not printed] bindings: [it]
597 expr (of non-IO type,
598 result showable) ==> let v = expr in print v >> return [v]
601 expr (of non-IO type,
602 result not showable) ==> error
606 hscStmt -- Compile a stmt all the way to an HValue, but don't run it
608 -> String -- The statement
609 -> IO (Maybe (HscEnv, [Name], HValue))
612 = do { maybe_stmt <- hscParseStmt (hsc_dflags hsc_env) stmt
613 ; case maybe_stmt of {
614 Nothing -> return Nothing ; -- Parse error
615 Just Nothing -> return Nothing ; -- Empty line
616 Just (Just parsed_stmt) -> do { -- The real stuff
618 -- Rename and typecheck it
619 let icontext = hsc_IC hsc_env
620 ; maybe_tc_result <- tcRnStmt hsc_env icontext parsed_stmt
622 ; case maybe_tc_result of {
623 Nothing -> return Nothing ;
624 Just (new_ic, bound_names, tc_expr) -> do {
626 -- Then desugar, code gen, and link it
627 ; hval <- compileExpr hsc_env iNTERACTIVE
628 (ic_rn_gbl_env new_ic)
632 ; return (Just (hsc_env{ hsc_IC=new_ic }, bound_names, hval))
635 hscTcExpr -- Typecheck an expression (but don't run it)
637 -> String -- The expression
640 hscTcExpr hsc_env expr
641 = do { maybe_stmt <- hscParseStmt (hsc_dflags hsc_env) expr
642 ; let icontext = hsc_IC hsc_env
643 ; case maybe_stmt of {
644 Nothing -> return Nothing ; -- Parse error
645 Just (Just (L _ (ExprStmt expr _ _)))
646 -> tcRnExpr hsc_env icontext expr ;
647 Just other -> do { errorMsg ("not an expression: `" ++ expr ++ "'") ;
651 hscKcType -- Find the kind of a type
653 -> String -- The type
656 hscKcType hsc_env str
657 = do { maybe_type <- hscParseType (hsc_dflags hsc_env) str
658 ; let icontext = hsc_IC hsc_env
659 ; case maybe_type of {
660 Just ty -> tcRnType hsc_env icontext ty ;
661 Just other -> do { errorMsg ("not an type: `" ++ str ++ "'") ;
663 Nothing -> return Nothing } }
668 hscParseStmt :: DynFlags -> String -> IO (Maybe (Maybe (LStmt RdrName)))
669 hscParseStmt = hscParseThing parseStmt
671 hscParseType :: DynFlags -> String -> IO (Maybe (LHsType RdrName))
672 hscParseType = hscParseThing parseType
674 hscParseIdentifier :: DynFlags -> String -> IO (Maybe (Located RdrName))
675 hscParseIdentifier = hscParseThing parseIdentifier
677 hscParseThing :: Outputable thing
679 -> DynFlags -> String
681 -- Nothing => Parse error (message already printed)
683 hscParseThing parser dflags str
684 = showPass dflags "Parser" >>
685 {-# SCC "Parser" #-} do
687 buf <- stringToStringBuffer str
689 let loc = mkSrcLoc FSLIT("<interactive>") 1 0
691 case unP parser (mkPState buf loc dflags) of {
693 PFailed span err -> do { printError span err;
698 --ToDo: can't free the string buffer until we've finished this
699 -- compilation sweep and all the identifiers have gone away.
700 dumpIfSet_dyn dflags Opt_D_dump_parsed "Parser" (ppr thing);
705 %************************************************************************
707 \subsection{Getting information about an identifer}
709 %************************************************************************
713 hscGetInfo -- like hscStmt, but deals with a single identifier
715 -> String -- The identifier
716 -> IO [GetInfoResult]
718 hscGetInfo hsc_env str
719 = do maybe_rdr_name <- hscParseIdentifier (hsc_dflags hsc_env) str
720 case maybe_rdr_name of {
721 Nothing -> return [];
722 Just (L _ rdr_name) -> do
724 maybe_tc_result <- tcRnGetInfo hsc_env (hsc_IC hsc_env) rdr_name
726 case maybe_tc_result of
728 Just things -> return things
733 %************************************************************************
735 Desugar, simplify, convert to bytecode, and link an expression
737 %************************************************************************
741 compileExpr :: HscEnv
742 -> Module -> GlobalRdrEnv -> TypeEnv
746 compileExpr hsc_env this_mod rdr_env type_env tc_expr
747 = do { let { dflags = hsc_dflags hsc_env ;
748 lint_on = dopt Opt_DoCoreLinting dflags }
751 ; ds_expr <- deSugarExpr hsc_env this_mod rdr_env type_env tc_expr
754 ; flat_expr <- flattenExpr hsc_env ds_expr
757 ; simpl_expr <- simplifyExpr dflags flat_expr
759 -- Tidy it (temporary, until coreSat does cloning)
760 ; tidy_expr <- tidyCoreExpr simpl_expr
762 -- Prepare for codegen
763 ; prepd_expr <- corePrepExpr dflags tidy_expr
766 -- ToDo: improve SrcLoc
768 case lintUnfolding noSrcLoc [] prepd_expr of
769 Just err -> pprPanic "compileExpr" err
775 ; bcos <- coreExprToBCOs dflags prepd_expr
778 ; hval <- linkExpr hsc_env bcos
786 %************************************************************************
788 Statistics on reading interfaces
790 %************************************************************************
793 dumpIfaceStats :: HscEnv -> IO ()
794 dumpIfaceStats hsc_env
795 = do { eps <- readIORef (hsc_EPS hsc_env)
796 ; dumpIfSet (dump_if_trace || dump_rn_stats)
797 "Interface statistics"
800 dflags = hsc_dflags hsc_env
801 dump_rn_stats = dopt Opt_D_dump_rn_stats dflags
802 dump_if_trace = dopt Opt_D_dump_if_trace dflags