Allow warning if could have been infered safe instead of explicit
[ghc.git] / compiler / main / HscMain.hs
1 {-# LANGUAGE BangPatterns, CPP, MagicHash, NondecreasingIndentation #-}
2
3 -------------------------------------------------------------------------------
4 --
5 -- | Main API for compiling plain Haskell source code.
6 --
7 -- This module implements compilation of a Haskell source. It is
8 -- /not/ concerned with preprocessing of source files; this is handled
9 -- in "DriverPipeline".
10 --
11 -- There are various entry points depending on what mode we're in:
12 -- "batch" mode (@--make@), "one-shot" mode (@-c@, @-S@ etc.), and
13 -- "interactive" mode (GHCi). There are also entry points for
14 -- individual passes: parsing, typechecking/renaming, desugaring, and
15 -- simplification.
16 --
17 -- All the functions here take an 'HscEnv' as a parameter, but none of
18 -- them return a new one: 'HscEnv' is treated as an immutable value
19 -- from here on in (although it has mutable components, for the
20 -- caches).
21 --
22 -- Warning messages are dealt with consistently throughout this API:
23 -- during compilation warnings are collected, and before any function
24 -- in @HscMain@ returns, the warnings are either printed, or turned
25 -- into a real compialtion error if the @-Werror@ flag is enabled.
26 --
27 -- (c) The GRASP/AQUA Project, Glasgow University, 1993-2000
28 --
29 -------------------------------------------------------------------------------
30
31 module HscMain
32 (
33 -- * Making an HscEnv
34 newHscEnv
35
36 -- * Compiling complete source files
37 , Messager, batchMsg
38 , HscStatus (..)
39 , hscCompileOneShot
40 , hscCompileCmmFile
41 , hscCompileCore
42
43 , genericHscCompileGetFrontendResult
44
45 , genModDetails
46 , hscSimpleIface
47 , hscWriteIface
48 , hscNormalIface
49 , hscGenHardCode
50 , hscInteractive
51
52 -- * Running passes separately
53 , hscParse
54 , hscTypecheckRename
55 , hscDesugar
56 , makeSimpleIface
57 , makeSimpleDetails
58 , hscSimplify -- ToDo, shouldn't really export this
59
60 -- * Support for interactive evaluation
61 , hscParseIdentifier
62 , hscTcRcLookupName
63 , hscTcRnGetInfo
64 , hscCheckSafe
65 , hscGetSafe
66 #ifdef GHCI
67 , hscIsGHCiMonad
68 , hscGetModuleInterface
69 , hscRnImportDecls
70 , hscTcRnLookupRdrName
71 , hscStmt, hscStmtWithLocation
72 , hscDecls, hscDeclsWithLocation
73 , hscTcExpr, hscImport, hscKcType
74 , hscCompileCoreExpr
75 -- * Low-level exports for hooks
76 , hscCompileCoreExpr'
77 #endif
78 -- We want to make sure that we export enough to be able to redefine
79 -- hscFileFrontEnd in client code
80 , hscParse', hscSimplify', hscDesugar', tcRnModule'
81 , getHscEnv
82 , hscSimpleIface', hscNormalIface'
83 , oneShotMsg
84 , hscFileFrontEnd, genericHscFrontend, dumpIfaceStats
85 ) where
86
87 #ifdef GHCI
88 import Id
89 import BasicTypes ( HValue )
90 import ByteCodeGen ( byteCodeGen, coreExprToBCOs )
91 import Linker
92 import CoreTidy ( tidyExpr )
93 import Type ( Type )
94 import PrelNames
95 import {- Kind parts of -} Type ( Kind )
96 import CoreMonad ( lintInteractiveExpr )
97 import DsMeta ( templateHaskellNames )
98 import VarEnv ( emptyTidyEnv )
99 import Panic
100
101 import GHC.Exts
102 #endif
103
104 import Module
105 import Packages
106 import RdrName
107 import HsSyn
108 import CoreSyn
109 import StringBuffer
110 import Parser
111 import Lexer
112 import SrcLoc
113 import TcRnDriver
114 import TcIface ( typecheckIface )
115 import TcRnMonad
116 import IfaceEnv ( initNameCache )
117 import LoadIface ( ifaceStats, initExternalPackageState )
118 import PrelInfo
119 import MkIface
120 import Desugar
121 import SimplCore
122 import TidyPgm
123 import CorePrep
124 import CoreToStg ( coreToStg )
125 import qualified StgCmm ( codeGen )
126 import StgSyn
127 import CostCentre
128 import ProfInit
129 import TyCon
130 import Name
131 import SimplStg ( stg2stg )
132 import Cmm
133 import CmmParse ( parseCmmFile )
134 import CmmBuildInfoTables
135 import CmmPipeline
136 import CmmInfo
137 import CodeOutput
138 import NameEnv ( emptyNameEnv )
139 import NameSet ( emptyNameSet )
140 import InstEnv
141 import FamInstEnv
142 import Fingerprint ( Fingerprint )
143 import Hooks
144
145 import DynFlags
146 import ErrUtils
147
148 import Outputable
149 import HscStats ( ppSourceStats )
150 import HscTypes
151 import FastString
152 import UniqFM ( emptyUFM )
153 import UniqSupply
154 import Bag
155 import Exception
156 import qualified Stream
157 import Stream (Stream)
158
159 import Util
160
161 import Data.List
162 import Control.Monad
163 import Data.Maybe
164 import Data.IORef
165 import System.FilePath as FilePath
166 import System.Directory
167
168 #include "HsVersions.h"
169
170
171 {- **********************************************************************
172 %* *
173 Initialisation
174 %* *
175 %********************************************************************* -}
176
177 newHscEnv :: DynFlags -> IO HscEnv
178 newHscEnv dflags = do
179 eps_var <- newIORef initExternalPackageState
180 us <- mkSplitUniqSupply 'r'
181 nc_var <- newIORef (initNameCache us knownKeyNames)
182 fc_var <- newIORef emptyUFM
183 mlc_var <- newIORef emptyModuleEnv
184 return HscEnv { hsc_dflags = dflags,
185 hsc_targets = [],
186 hsc_mod_graph = [],
187 hsc_IC = emptyInteractiveContext dflags,
188 hsc_HPT = emptyHomePackageTable,
189 hsc_EPS = eps_var,
190 hsc_NC = nc_var,
191 hsc_FC = fc_var,
192 hsc_MLC = mlc_var,
193 hsc_type_env_var = Nothing }
194
195
196 knownKeyNames :: [Name] -- Put here to avoid loops involving DsMeta,
197 knownKeyNames = -- where templateHaskellNames are defined
198 map getName wiredInThings
199 ++ basicKnownKeyNames
200 #ifdef GHCI
201 ++ templateHaskellNames
202 #endif
203
204 -- -----------------------------------------------------------------------------
205
206 getWarnings :: Hsc WarningMessages
207 getWarnings = Hsc $ \_ w -> return (w, w)
208
209 clearWarnings :: Hsc ()
210 clearWarnings = Hsc $ \_ _ -> return ((), emptyBag)
211
212 logWarnings :: WarningMessages -> Hsc ()
213 logWarnings w = Hsc $ \_ w0 -> return ((), w0 `unionBags` w)
214
215 getHscEnv :: Hsc HscEnv
216 getHscEnv = Hsc $ \e w -> return (e, w)
217
218 handleWarnings :: Hsc ()
219 handleWarnings = do
220 dflags <- getDynFlags
221 w <- getWarnings
222 liftIO $ printOrThrowWarnings dflags w
223 clearWarnings
224
225 -- | log warning in the monad, and if there are errors then
226 -- throw a SourceError exception.
227 logWarningsReportErrors :: Messages -> Hsc ()
228 logWarningsReportErrors (warns,errs) = do
229 logWarnings warns
230 when (not $ isEmptyBag errs) $ throwErrors errs
231
232 -- | Throw some errors.
233 throwErrors :: ErrorMessages -> Hsc a
234 throwErrors = liftIO . throwIO . mkSrcErr
235
236 -- | Deal with errors and warnings returned by a compilation step
237 --
238 -- In order to reduce dependencies to other parts of the compiler, functions
239 -- outside the "main" parts of GHC return warnings and errors as a parameter
240 -- and signal success via by wrapping the result in a 'Maybe' type. This
241 -- function logs the returned warnings and propagates errors as exceptions
242 -- (of type 'SourceError').
243 --
244 -- This function assumes the following invariants:
245 --
246 -- 1. If the second result indicates success (is of the form 'Just x'),
247 -- there must be no error messages in the first result.
248 --
249 -- 2. If there are no error messages, but the second result indicates failure
250 -- there should be warnings in the first result. That is, if the action
251 -- failed, it must have been due to the warnings (i.e., @-Werror@).
252 ioMsgMaybe :: IO (Messages, Maybe a) -> Hsc a
253 ioMsgMaybe ioA = do
254 ((warns,errs), mb_r) <- liftIO ioA
255 logWarnings warns
256 case mb_r of
257 Nothing -> throwErrors errs
258 Just r -> ASSERT( isEmptyBag errs ) return r
259
260 -- | like ioMsgMaybe, except that we ignore error messages and return
261 -- 'Nothing' instead.
262 ioMsgMaybe' :: IO (Messages, Maybe a) -> Hsc (Maybe a)
263 ioMsgMaybe' ioA = do
264 ((warns,_errs), mb_r) <- liftIO $ ioA
265 logWarnings warns
266 return mb_r
267
268 -- -----------------------------------------------------------------------------
269 -- | Lookup things in the compiler's environment
270
271 #ifdef GHCI
272 hscTcRnLookupRdrName :: HscEnv -> RdrName -> IO [Name]
273 hscTcRnLookupRdrName hsc_env0 rdr_name = runInteractiveHsc hsc_env0 $ do
274 hsc_env <- getHscEnv
275 ioMsgMaybe $ tcRnLookupRdrName hsc_env rdr_name
276 #endif
277
278 hscTcRcLookupName :: HscEnv -> Name -> IO (Maybe TyThing)
279 hscTcRcLookupName hsc_env0 name = runInteractiveHsc hsc_env0 $ do
280 hsc_env <- getHscEnv
281 ioMsgMaybe' $ tcRnLookupName hsc_env name
282 -- ignore errors: the only error we're likely to get is
283 -- "name not found", and the Maybe in the return type
284 -- is used to indicate that.
285
286 hscTcRnGetInfo :: HscEnv -> Name -> IO (Maybe (TyThing, Fixity, [ClsInst], [FamInst]))
287 hscTcRnGetInfo hsc_env0 name
288 = runInteractiveHsc hsc_env0 $
289 do { hsc_env <- getHscEnv
290 ; ioMsgMaybe' $ tcRnGetInfo hsc_env name }
291
292 #ifdef GHCI
293 hscIsGHCiMonad :: HscEnv -> String -> IO Name
294 hscIsGHCiMonad hsc_env name
295 = runHsc hsc_env $ ioMsgMaybe $ isGHCiMonad hsc_env name
296
297 hscGetModuleInterface :: HscEnv -> Module -> IO ModIface
298 hscGetModuleInterface hsc_env0 mod = runInteractiveHsc hsc_env0 $ do
299 hsc_env <- getHscEnv
300 ioMsgMaybe $ getModuleInterface hsc_env mod
301
302 -- -----------------------------------------------------------------------------
303 -- | Rename some import declarations
304 hscRnImportDecls :: HscEnv -> [LImportDecl RdrName] -> IO GlobalRdrEnv
305 hscRnImportDecls hsc_env0 import_decls = runInteractiveHsc hsc_env0 $ do
306 hsc_env <- getHscEnv
307 ioMsgMaybe $ tcRnImportDecls hsc_env import_decls
308 #endif
309
310 -- -----------------------------------------------------------------------------
311 -- | parse a file, returning the abstract syntax
312
313 hscParse :: HscEnv -> ModSummary -> IO HsParsedModule
314 hscParse hsc_env mod_summary = runHsc hsc_env $ hscParse' mod_summary
315
316 -- internal version, that doesn't fail due to -Werror
317 hscParse' :: ModSummary -> Hsc HsParsedModule
318 hscParse' mod_summary = do
319 dflags <- getDynFlags
320 let src_filename = ms_hspp_file mod_summary
321 maybe_src_buf = ms_hspp_buf mod_summary
322
323 -------------------------- Parser ----------------
324 liftIO $ showPass dflags "Parser"
325 {-# SCC "Parser" #-} do
326
327 -- sometimes we already have the buffer in memory, perhaps
328 -- because we needed to parse the imports out of it, or get the
329 -- module name.
330 buf <- case maybe_src_buf of
331 Just b -> return b
332 Nothing -> liftIO $ hGetStringBuffer src_filename
333
334 let loc = mkRealSrcLoc (mkFastString src_filename) 1 1
335
336 case unP parseModule (mkPState dflags buf loc) of
337 PFailed span err ->
338 liftIO $ throwOneError (mkPlainErrMsg dflags span err)
339
340 POk pst rdr_module -> do
341 logWarningsReportErrors (getMessages pst)
342 liftIO $ dumpIfSet_dyn dflags Opt_D_dump_parsed "Parser" $
343 ppr rdr_module
344 liftIO $ dumpIfSet_dyn dflags Opt_D_source_stats "Source Statistics" $
345 ppSourceStats False rdr_module
346
347 -- To get the list of extra source files, we take the list
348 -- that the parser gave us,
349 -- - eliminate files beginning with '<'. gcc likes to use
350 -- pseudo-filenames like "<built-in>" and "<command-line>"
351 -- - normalise them (elimiante differences between ./f and f)
352 -- - filter out the preprocessed source file
353 -- - filter out anything beginning with tmpdir
354 -- - remove duplicates
355 -- - filter out the .hs/.lhs source filename if we have one
356 --
357 let n_hspp = FilePath.normalise src_filename
358 srcs0 = nub $ filter (not . (tmpDir dflags `isPrefixOf`))
359 $ filter (not . (== n_hspp))
360 $ map FilePath.normalise
361 $ filter (not . (isPrefixOf "<"))
362 $ map unpackFS
363 $ srcfiles pst
364 srcs1 = case ml_hs_file (ms_location mod_summary) of
365 Just f -> filter (/= FilePath.normalise f) srcs0
366 Nothing -> srcs0
367
368 -- sometimes we see source files from earlier
369 -- preprocessing stages that cannot be found, so just
370 -- filter them out:
371 srcs2 <- liftIO $ filterM doesFileExist srcs1
372
373 return HsParsedModule {
374 hpm_module = rdr_module,
375 hpm_src_files = srcs2
376 }
377
378 -- XXX: should this really be a Maybe X? Check under which circumstances this
379 -- can become a Nothing and decide whether this should instead throw an
380 -- exception/signal an error.
381 type RenamedStuff =
382 (Maybe (HsGroup Name, [LImportDecl Name], Maybe [LIE Name],
383 Maybe LHsDocString))
384
385 -- | Rename and typecheck a module, additionally returning the renamed syntax
386 hscTypecheckRename :: HscEnv -> ModSummary -> HsParsedModule
387 -> IO (TcGblEnv, RenamedStuff)
388 hscTypecheckRename hsc_env mod_summary rdr_module = runHsc hsc_env $ do
389 tc_result <- tcRnModule' hsc_env mod_summary True rdr_module
390
391 -- This 'do' is in the Maybe monad!
392 let rn_info = do decl <- tcg_rn_decls tc_result
393 let imports = tcg_rn_imports tc_result
394 exports = tcg_rn_exports tc_result
395 doc_hdr = tcg_doc_hdr tc_result
396 return (decl,imports,exports,doc_hdr)
397
398 return (tc_result, rn_info)
399
400 -- wrapper around tcRnModule to handle safe haskell extras
401 tcRnModule' :: HscEnv -> ModSummary -> Bool -> HsParsedModule
402 -> Hsc TcGblEnv
403 tcRnModule' hsc_env sum save_rn_syntax mod = do
404 tcg_res <- {-# SCC "Typecheck-Rename" #-}
405 ioMsgMaybe $
406 tcRnModule hsc_env (ms_hsc_src sum) save_rn_syntax mod
407
408 tcSafeOK <- liftIO $ readIORef (tcg_safeInfer tcg_res)
409 dflags <- getDynFlags
410 let allSafeOK = safeInferred dflags && tcSafeOK
411
412 -- end of the safe haskell line, how to respond to user?
413 if not (safeHaskellOn dflags) || (safeInferOn dflags && not allSafeOK)
414 -- if safe Haskell off or safe infer failed, mark unsafe
415 then markUnsafe tcg_res emptyBag
416
417 -- module (could be) safe, throw warning if needed
418 else do
419 tcg_res' <- hscCheckSafeImports tcg_res
420 safe <- liftIO $ readIORef (tcg_safeInfer tcg_res')
421 when (safe && wopt Opt_WarnSafe dflags)
422 (logWarnings $ unitBag $ mkPlainWarnMsg dflags
423 (warnSafeOnLoc dflags) $ errSafe tcg_res')
424 return tcg_res'
425 where
426 pprMod t = ppr $ moduleName $ tcg_mod t
427 errSafe t = quotes (pprMod t) <+> text "has been inferred as safe!"
428
429 -- | Convert a typechecked module to Core
430 hscDesugar :: HscEnv -> ModSummary -> TcGblEnv -> IO ModGuts
431 hscDesugar hsc_env mod_summary tc_result =
432 runHsc hsc_env $ hscDesugar' (ms_location mod_summary) tc_result
433
434 hscDesugar' :: ModLocation -> TcGblEnv -> Hsc ModGuts
435 hscDesugar' mod_location tc_result = do
436 hsc_env <- getHscEnv
437 r <- ioMsgMaybe $
438 {-# SCC "deSugar" #-}
439 deSugar hsc_env mod_location tc_result
440
441 -- always check -Werror after desugaring, this is the last opportunity for
442 -- warnings to arise before the backend.
443 handleWarnings
444 return r
445
446 -- | Make a 'ModIface' from the results of typechecking. Used when
447 -- not optimising, and the interface doesn't need to contain any
448 -- unfoldings or other cross-module optimisation info.
449 -- ToDo: the old interface is only needed to get the version numbers,
450 -- we should use fingerprint versions instead.
451 makeSimpleIface :: HscEnv -> Maybe ModIface -> TcGblEnv -> ModDetails
452 -> IO (ModIface,Bool)
453 makeSimpleIface hsc_env maybe_old_iface tc_result details = runHsc hsc_env $ do
454 safe_mode <- hscGetSafeMode tc_result
455 ioMsgMaybe $ do
456 mkIfaceTc hsc_env (fmap mi_iface_hash maybe_old_iface) safe_mode
457 details tc_result
458
459 -- | Make a 'ModDetails' from the results of typechecking. Used when
460 -- typechecking only, as opposed to full compilation.
461 makeSimpleDetails :: HscEnv -> TcGblEnv -> IO ModDetails
462 makeSimpleDetails hsc_env tc_result = mkBootModDetailsTc hsc_env tc_result
463
464
465 {- **********************************************************************
466 %* *
467 The main compiler pipeline
468 %* *
469 %********************************************************************* -}
470
471 {-
472 --------------------------------
473 The compilation proper
474 --------------------------------
475
476 It's the task of the compilation proper to compile Haskell, hs-boot and core
477 files to either byte-code, hard-code (C, asm, LLVM, ect) or to nothing at all
478 (the module is still parsed and type-checked. This feature is mostly used by
479 IDE's and the likes). Compilation can happen in either 'one-shot', 'batch',
480 'nothing', or 'interactive' mode. 'One-shot' mode targets hard-code, 'batch'
481 mode targets hard-code, 'nothing' mode targets nothing and 'interactive' mode
482 targets byte-code.
483
484 The modes are kept separate because of their different types and meanings:
485
486 * In 'one-shot' mode, we're only compiling a single file and can therefore
487 discard the new ModIface and ModDetails. This is also the reason it only
488 targets hard-code; compiling to byte-code or nothing doesn't make sense when
489 we discard the result.
490
491 * 'Batch' mode is like 'one-shot' except that we keep the resulting ModIface
492 and ModDetails. 'Batch' mode doesn't target byte-code since that require us to
493 return the newly compiled byte-code.
494
495 * 'Nothing' mode has exactly the same type as 'batch' mode but they're still
496 kept separate. This is because compiling to nothing is fairly special: We
497 don't output any interface files, we don't run the simplifier and we don't
498 generate any code.
499
500 * 'Interactive' mode is similar to 'batch' mode except that we return the
501 compiled byte-code together with the ModIface and ModDetails.
502
503 Trying to compile a hs-boot file to byte-code will result in a run-time error.
504 This is the only thing that isn't caught by the type-system.
505 -}
506
507
508 type Messager = HscEnv -> (Int,Int) -> RecompileRequired -> ModSummary -> IO ()
509
510 genericHscCompileGetFrontendResult ::
511 Bool -- always do basic recompilation check?
512 -> Maybe TcGblEnv
513 -> Maybe Messager
514 -> HscEnv
515 -> ModSummary
516 -> SourceModified
517 -> Maybe ModIface -- Old interface, if available
518 -> (Int,Int) -- (i,n) = module i of n (for msgs)
519 -> IO (Either ModIface (TcGblEnv, Maybe Fingerprint))
520
521 genericHscCompileGetFrontendResult
522 always_do_basic_recompilation_check m_tc_result
523 mHscMessage hsc_env mod_summary source_modified mb_old_iface mod_index
524 = do
525
526 let msg what = case mHscMessage of
527 Just hscMessage -> hscMessage hsc_env mod_index what mod_summary
528 Nothing -> return ()
529
530 skip iface = do
531 msg UpToDate
532 return $ Left iface
533
534 compile mb_old_hash reason = do
535 msg reason
536 tc_result <- runHsc hsc_env $ genericHscFrontend mod_summary
537 return $ Right (tc_result, mb_old_hash)
538
539 stable = case source_modified of
540 SourceUnmodifiedAndStable -> True
541 _ -> False
542
543 case m_tc_result of
544 Just tc_result
545 | not always_do_basic_recompilation_check ->
546 return $ Right (tc_result, Nothing)
547 _ -> do
548 (recomp_reqd, mb_checked_iface)
549 <- {-# SCC "checkOldIface" #-}
550 checkOldIface hsc_env mod_summary
551 source_modified mb_old_iface
552 -- save the interface that comes back from checkOldIface.
553 -- In one-shot mode we don't have the old iface until this
554 -- point, when checkOldIface reads it from the disk.
555 let mb_old_hash = fmap mi_iface_hash mb_checked_iface
556
557 case mb_checked_iface of
558 Just iface | not (recompileRequired recomp_reqd) ->
559 -- If the module used TH splices when it was last
560 -- compiled, then the recompilation check is not
561 -- accurate enough (#481) and we must ignore
562 -- it. However, if the module is stable (none of
563 -- the modules it depends on, directly or
564 -- indirectly, changed), then we *can* skip
565 -- recompilation. This is why the SourceModified
566 -- type contains SourceUnmodifiedAndStable, and
567 -- it's pretty important: otherwise ghc --make
568 -- would always recompile TH modules, even if
569 -- nothing at all has changed. Stability is just
570 -- the same check that make is doing for us in
571 -- one-shot mode.
572 case m_tc_result of
573 Nothing
574 | mi_used_th iface && not stable ->
575 compile mb_old_hash (RecompBecause "TH")
576 _ ->
577 skip iface
578 _ ->
579 case m_tc_result of
580 Nothing -> compile mb_old_hash recomp_reqd
581 Just tc_result ->
582 return $ Right (tc_result, mb_old_hash)
583
584 genericHscFrontend :: ModSummary -> Hsc TcGblEnv
585 genericHscFrontend mod_summary =
586 getHooked hscFrontendHook genericHscFrontend' >>= ($ mod_summary)
587
588 genericHscFrontend' :: ModSummary -> Hsc TcGblEnv
589 genericHscFrontend' mod_summary = hscFileFrontEnd mod_summary
590
591 --------------------------------------------------------------
592 -- Compilers
593 --------------------------------------------------------------
594
595 hscCompileOneShot :: HscEnv
596 -> ModSummary
597 -> SourceModified
598 -> IO HscStatus
599 hscCompileOneShot env =
600 lookupHook hscCompileOneShotHook hscCompileOneShot' (hsc_dflags env) env
601
602 -- Compile Haskell/boot in OneShot mode.
603 hscCompileOneShot' :: HscEnv
604 -> ModSummary
605 -> SourceModified
606 -> IO HscStatus
607 hscCompileOneShot' hsc_env mod_summary src_changed
608 = do
609 -- One-shot mode needs a knot-tying mutable variable for interface
610 -- files. See TcRnTypes.TcGblEnv.tcg_type_env_var.
611 type_env_var <- newIORef emptyNameEnv
612 let mod = ms_mod mod_summary
613 hsc_env' = hsc_env{ hsc_type_env_var = Just (mod, type_env_var) }
614
615 msg what = oneShotMsg hsc_env' what
616
617 skip = do msg UpToDate
618 dumpIfaceStats hsc_env'
619 return HscUpToDate
620
621 compile mb_old_hash reason = runHsc hsc_env' $ do
622 liftIO $ msg reason
623 tc_result <- genericHscFrontend mod_summary
624 guts0 <- hscDesugar' (ms_location mod_summary) tc_result
625 dflags <- getDynFlags
626 case hscTarget dflags of
627 HscNothing -> do
628 when (gopt Opt_WriteInterface dflags) $ liftIO $ do
629 (iface, changed, _details) <- hscSimpleIface hsc_env tc_result mb_old_hash
630 hscWriteIface dflags iface changed mod_summary
631 return HscNotGeneratingCode
632 _ ->
633 case ms_hsc_src mod_summary of
634 HsBootFile ->
635 do (iface, changed, _) <- hscSimpleIface' tc_result mb_old_hash
636 liftIO $ hscWriteIface dflags iface changed mod_summary
637 return HscUpdateBoot
638 _ ->
639 do guts <- hscSimplify' guts0
640 (iface, changed, _details, cgguts) <- hscNormalIface' guts mb_old_hash
641 liftIO $ hscWriteIface dflags iface changed mod_summary
642 return $ HscRecomp cgguts mod_summary
643
644 -- XXX This is always False, because in one-shot mode the
645 -- concept of stability does not exist. The driver never
646 -- passes SourceUnmodifiedAndStable in here.
647 stable = case src_changed of
648 SourceUnmodifiedAndStable -> True
649 _ -> False
650
651 (recomp_reqd, mb_checked_iface)
652 <- {-# SCC "checkOldIface" #-}
653 checkOldIface hsc_env' mod_summary src_changed Nothing
654 -- save the interface that comes back from checkOldIface.
655 -- In one-shot mode we don't have the old iface until this
656 -- point, when checkOldIface reads it from the disk.
657 let mb_old_hash = fmap mi_iface_hash mb_checked_iface
658
659 case mb_checked_iface of
660 Just iface | not (recompileRequired recomp_reqd) ->
661 -- If the module used TH splices when it was last compiled,
662 -- then the recompilation check is not accurate enough (#481)
663 -- and we must ignore it. However, if the module is stable
664 -- (none of the modules it depends on, directly or indirectly,
665 -- changed), then we *can* skip recompilation. This is why
666 -- the SourceModified type contains SourceUnmodifiedAndStable,
667 -- and it's pretty important: otherwise ghc --make would
668 -- always recompile TH modules, even if nothing at all has
669 -- changed. Stability is just the same check that make is
670 -- doing for us in one-shot mode.
671 if mi_used_th iface && not stable
672 then compile mb_old_hash (RecompBecause "TH")
673 else skip
674 _ ->
675 compile mb_old_hash recomp_reqd
676
677 --------------------------------------------------------------
678 -- NoRecomp handlers
679 --------------------------------------------------------------
680
681 genModDetails :: HscEnv -> ModIface -> IO ModDetails
682 genModDetails hsc_env old_iface
683 = do
684 new_details <- {-# SCC "tcRnIface" #-}
685 initIfaceCheck hsc_env (typecheckIface old_iface)
686 dumpIfaceStats hsc_env
687 return new_details
688
689 --------------------------------------------------------------
690 -- Progress displayers.
691 --------------------------------------------------------------
692
693 oneShotMsg :: HscEnv -> RecompileRequired -> IO ()
694 oneShotMsg hsc_env recomp =
695 case recomp of
696 UpToDate ->
697 compilationProgressMsg (hsc_dflags hsc_env) $
698 "compilation IS NOT required"
699 _ ->
700 return ()
701
702 batchMsg :: Messager
703 batchMsg hsc_env mod_index recomp mod_summary =
704 case recomp of
705 MustCompile -> showMsg "Compiling " ""
706 UpToDate
707 | verbosity (hsc_dflags hsc_env) >= 2 -> showMsg "Skipping " ""
708 | otherwise -> return ()
709 RecompBecause reason -> showMsg "Compiling " (" [" ++ reason ++ "]")
710 where
711 dflags = hsc_dflags hsc_env
712 showMsg msg reason =
713 compilationProgressMsg dflags $
714 (showModuleIndex mod_index ++
715 msg ++ showModMsg dflags (hscTarget dflags)
716 (recompileRequired recomp) mod_summary)
717 ++ reason
718
719 --------------------------------------------------------------
720 -- FrontEnds
721 --------------------------------------------------------------
722
723 hscFileFrontEnd :: ModSummary -> Hsc TcGblEnv
724 hscFileFrontEnd mod_summary = do
725 hpm <- hscParse' mod_summary
726 hsc_env <- getHscEnv
727 tcg_env <- tcRnModule' hsc_env mod_summary False hpm
728 return tcg_env
729
730 --------------------------------------------------------------
731 -- Safe Haskell
732 --------------------------------------------------------------
733
734 -- Note [Safe Haskell Trust Check]
735 -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
736 -- Safe Haskell checks that an import is trusted according to the following
737 -- rules for an import of module M that resides in Package P:
738 --
739 -- * If M is recorded as Safe and all its trust dependencies are OK
740 -- then M is considered safe.
741 -- * If M is recorded as Trustworthy and P is considered trusted and
742 -- all M's trust dependencies are OK then M is considered safe.
743 --
744 -- By trust dependencies we mean that the check is transitive. So if
745 -- a module M that is Safe relies on a module N that is trustworthy,
746 -- importing module M will first check (according to the second case)
747 -- that N is trusted before checking M is trusted.
748 --
749 -- This is a minimal description, so please refer to the user guide
750 -- for more details. The user guide is also considered the authoritative
751 -- source in this matter, not the comments or code.
752
753
754 -- Note [Safe Haskell Inference]
755 -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
756 -- Safe Haskell does Safe inference on modules that don't have any specific
757 -- safe haskell mode flag. The basic aproach to this is:
758 -- * When deciding if we need to do a Safe language check, treat
759 -- an unmarked module as having -XSafe mode specified.
760 -- * For checks, don't throw errors but return them to the caller.
761 -- * Caller checks if there are errors:
762 -- * For modules explicitly marked -XSafe, we throw the errors.
763 -- * For unmarked modules (inference mode), we drop the errors
764 -- and mark the module as being Unsafe.
765
766
767 -- | Check that the safe imports of the module being compiled are valid.
768 -- If not we either issue a compilation error if the module is explicitly
769 -- using Safe Haskell, or mark the module as unsafe if we're in safe
770 -- inference mode.
771 hscCheckSafeImports :: TcGblEnv -> Hsc TcGblEnv
772 hscCheckSafeImports tcg_env = do
773 dflags <- getDynFlags
774 tcg_env' <- checkSafeImports dflags tcg_env
775 case safeLanguageOn dflags of
776 True -> do
777 -- XSafe: we nuke user written RULES
778 logWarnings $ warns dflags (tcg_rules tcg_env')
779 return tcg_env' { tcg_rules = [] }
780 False
781 -- SafeInferred: user defined RULES, so not safe
782 | safeInferOn dflags && not (null $ tcg_rules tcg_env')
783 -> markUnsafe tcg_env' $ warns dflags (tcg_rules tcg_env')
784
785 -- Trustworthy OR SafeInferred: with no RULES
786 | otherwise
787 -> return tcg_env'
788
789 where
790 warns dflags rules = listToBag $ map (warnRules dflags) rules
791 warnRules dflags (L loc (HsRule n _ _ _ _ _ _)) =
792 mkPlainWarnMsg dflags loc $
793 text "Rule \"" <> ftext n <> text "\" ignored" $+$
794 text "User defined rules are disabled under Safe Haskell"
795
796 -- | Validate that safe imported modules are actually safe. For modules in the
797 -- HomePackage (the package the module we are compiling in resides) this just
798 -- involves checking its trust type is 'Safe' or 'Trustworthy'. For modules
799 -- that reside in another package we also must check that the external pacakge
800 -- is trusted. See the Note [Safe Haskell Trust Check] above for more
801 -- information.
802 --
803 -- The code for this is quite tricky as the whole algorithm is done in a few
804 -- distinct phases in different parts of the code base. See
805 -- RnNames.rnImportDecl for where package trust dependencies for a module are
806 -- collected and unioned. Specifically see the Note [RnNames . Tracking Trust
807 -- Transitively] and the Note [RnNames . Trust Own Package].
808 checkSafeImports :: DynFlags -> TcGblEnv -> Hsc TcGblEnv
809 checkSafeImports dflags tcg_env
810 = do
811 -- We want to use the warning state specifically for detecting if safe
812 -- inference has failed, so store and clear any existing warnings.
813 oldErrs <- getWarnings
814 clearWarnings
815
816 imps <- mapM condense imports'
817 pkgs <- mapM checkSafe imps
818
819 -- grab any safe haskell specific errors and restore old warnings
820 errs <- getWarnings
821 clearWarnings
822 logWarnings oldErrs
823
824 -- See the Note [Safe Haskell Inference]
825 case (not $ isEmptyBag errs) of
826
827 -- We have errors!
828 True ->
829 -- did we fail safe inference or fail -XSafe?
830 case safeInferOn dflags of
831 True -> markUnsafe tcg_env errs
832 False -> liftIO . throwIO . mkSrcErr $ errs
833
834 -- All good matey!
835 False -> do
836 when (packageTrustOn dflags) $ checkPkgTrust dflags pkg_reqs
837 -- add in trusted package requirements for this module
838 let new_trust = emptyImportAvails { imp_trust_pkgs = catMaybes pkgs }
839 return tcg_env { tcg_imports = imp_info `plusImportAvails` new_trust }
840
841 where
842 imp_info = tcg_imports tcg_env -- ImportAvails
843 imports = imp_mods imp_info -- ImportedMods
844 imports' = moduleEnvToList imports -- (Module, [ImportedModsVal])
845 pkg_reqs = imp_trust_pkgs imp_info -- [PackageKey]
846
847 condense :: (Module, [ImportedModsVal]) -> Hsc (Module, SrcSpan, IsSafeImport)
848 condense (_, []) = panic "HscMain.condense: Pattern match failure!"
849 condense (m, x:xs) = do (_,_,l,s) <- foldlM cond' x xs
850 -- we turn all imports into safe ones when
851 -- inference mode is on.
852 let s' = if safeInferOn dflags &&
853 safeHaskell dflags == Sf_None
854 then True else s
855 return (m, l, s')
856
857 -- ImportedModsVal = (ModuleName, Bool, SrcSpan, IsSafeImport)
858 cond' :: ImportedModsVal -> ImportedModsVal -> Hsc ImportedModsVal
859 cond' v1@(m1,_,l1,s1) (_,_,_,s2)
860 | s1 /= s2
861 = throwErrors $ unitBag $ mkPlainErrMsg dflags l1
862 (text "Module" <+> ppr m1 <+>
863 (text $ "is imported both as a safe and unsafe import!"))
864 | otherwise
865 = return v1
866
867 -- easier interface to work with
868 checkSafe (_, _, False) = return Nothing
869 checkSafe (m, l, True ) = fst `fmap` hscCheckSafe' dflags m l
870
871 -- | Check that a module is safe to import.
872 --
873 -- We return True to indicate the import is safe and False otherwise
874 -- although in the False case an exception may be thrown first.
875 hscCheckSafe :: HscEnv -> Module -> SrcSpan -> IO Bool
876 hscCheckSafe hsc_env m l = runHsc hsc_env $ do
877 dflags <- getDynFlags
878 pkgs <- snd `fmap` hscCheckSafe' dflags m l
879 when (packageTrustOn dflags) $ checkPkgTrust dflags pkgs
880 errs <- getWarnings
881 return $ isEmptyBag errs
882
883 -- | Return if a module is trusted and the pkgs it depends on to be trusted.
884 hscGetSafe :: HscEnv -> Module -> SrcSpan -> IO (Bool, [PackageKey])
885 hscGetSafe hsc_env m l = runHsc hsc_env $ do
886 dflags <- getDynFlags
887 (self, pkgs) <- hscCheckSafe' dflags m l
888 good <- isEmptyBag `fmap` getWarnings
889 clearWarnings -- don't want them printed...
890 let pkgs' | Just p <- self = p:pkgs
891 | otherwise = pkgs
892 return (good, pkgs')
893
894 -- | Is a module trusted? If not, throw or log errors depending on the type.
895 -- Return (regardless of trusted or not) if the trust type requires the modules
896 -- own package be trusted and a list of other packages required to be trusted
897 -- (these later ones haven't been checked) but the own package trust has been.
898 hscCheckSafe' :: DynFlags -> Module -> SrcSpan -> Hsc (Maybe PackageKey, [PackageKey])
899 hscCheckSafe' dflags m l = do
900 (tw, pkgs) <- isModSafe m l
901 case tw of
902 False -> return (Nothing, pkgs)
903 True | isHomePkg m -> return (Nothing, pkgs)
904 | otherwise -> return (Just $ modulePackageKey m, pkgs)
905 where
906 isModSafe :: Module -> SrcSpan -> Hsc (Bool, [PackageKey])
907 isModSafe m l = do
908 iface <- lookup' m
909 case iface of
910 -- can't load iface to check trust!
911 Nothing -> throwErrors $ unitBag $ mkPlainErrMsg dflags l
912 $ text "Can't load the interface file for" <+> ppr m
913 <> text ", to check that it can be safely imported"
914
915 -- got iface, check trust
916 Just iface' ->
917 let trust = getSafeMode $ mi_trust iface'
918 trust_own_pkg = mi_trust_pkg iface'
919 -- check module is trusted
920 safeM = trust `elem` [Sf_Safe, Sf_Trustworthy]
921 -- check package is trusted
922 safeP = packageTrusted trust trust_own_pkg m
923 -- pkg trust reqs
924 pkgRs = map fst $ filter snd $ dep_pkgs $ mi_deps iface'
925 -- General errors we throw but Safe errors we log
926 errs = case (safeM, safeP) of
927 (True, True ) -> emptyBag
928 (True, False) -> pkgTrustErr
929 (False, _ ) -> modTrustErr
930 in do
931 logWarnings errs
932 return (trust == Sf_Trustworthy, pkgRs)
933
934 where
935 pkgTrustErr = unitBag $ mkPlainErrMsg dflags l $
936 sep [ ppr (moduleName m)
937 <> text ": Can't be safely imported!"
938 , text "The package (" <> ppr (modulePackageKey m)
939 <> text ") the module resides in isn't trusted."
940 ]
941 modTrustErr = unitBag $ mkPlainErrMsg dflags l $
942 sep [ ppr (moduleName m)
943 <> text ": Can't be safely imported!"
944 , text "The module itself isn't safe." ]
945
946 -- | Check the package a module resides in is trusted. Safe compiled
947 -- modules are trusted without requiring that their package is trusted. For
948 -- trustworthy modules, modules in the home package are trusted but
949 -- otherwise we check the package trust flag.
950 packageTrusted :: SafeHaskellMode -> Bool -> Module -> Bool
951 packageTrusted Sf_None _ _ = False -- shouldn't hit these cases
952 packageTrusted Sf_Unsafe _ _ = False -- prefer for completeness.
953 packageTrusted _ _ _
954 | not (packageTrustOn dflags) = True
955 packageTrusted Sf_Safe False _ = True
956 packageTrusted _ _ m
957 | isHomePkg m = True
958 | otherwise = trusted $ getPackageDetails (pkgState dflags)
959 (modulePackageKey m)
960
961 lookup' :: Module -> Hsc (Maybe ModIface)
962 lookup' m = do
963 hsc_env <- getHscEnv
964 hsc_eps <- liftIO $ hscEPS hsc_env
965 let pkgIfaceT = eps_PIT hsc_eps
966 homePkgT = hsc_HPT hsc_env
967 iface = lookupIfaceByModule dflags homePkgT pkgIfaceT m
968 #ifdef GHCI
969 -- the 'lookupIfaceByModule' method will always fail when calling from GHCi
970 -- as the compiler hasn't filled in the various module tables
971 -- so we need to call 'getModuleInterface' to load from disk
972 iface' <- case iface of
973 Just _ -> return iface
974 Nothing -> snd `fmap` (liftIO $ getModuleInterface hsc_env m)
975 return iface'
976 #else
977 return iface
978 #endif
979
980
981 isHomePkg :: Module -> Bool
982 isHomePkg m
983 | thisPackage dflags == modulePackageKey m = True
984 | otherwise = False
985
986 -- | Check the list of packages are trusted.
987 checkPkgTrust :: DynFlags -> [PackageKey] -> Hsc ()
988 checkPkgTrust dflags pkgs =
989 case errors of
990 [] -> return ()
991 _ -> (liftIO . throwIO . mkSrcErr . listToBag) errors
992 where
993 errors = catMaybes $ map go pkgs
994 go pkg
995 | trusted $ getPackageDetails (pkgState dflags) pkg
996 = Nothing
997 | otherwise
998 = Just $ mkPlainErrMsg dflags noSrcSpan
999 $ text "The package (" <> ppr pkg <> text ") is required" <>
1000 text " to be trusted but it isn't!"
1001
1002 -- | Set module to unsafe and (potentially) wipe trust information.
1003 --
1004 -- Make sure to call this method to set a module to inferred unsafe,
1005 -- it should be a central and single failure method. We only wipe the trust
1006 -- information when we aren't in a specific Safe Haskell mode.
1007 markUnsafe :: TcGblEnv -> WarningMessages -> Hsc TcGblEnv
1008 markUnsafe tcg_env whyUnsafe = do
1009 dflags <- getDynFlags
1010
1011 when (wopt Opt_WarnUnsafe dflags)
1012 (logWarnings $ unitBag $
1013 mkPlainWarnMsg dflags (warnUnsafeOnLoc dflags) (whyUnsafe' dflags))
1014
1015 liftIO $ writeIORef (tcg_safeInfer tcg_env) False
1016 -- NOTE: Only wipe trust when not in an explicity safe haskell mode. Other
1017 -- times inference may be on but we are in Trustworthy mode -- so we want
1018 -- to record safe-inference failed but not wipe the trust dependencies.
1019 case safeHaskell dflags == Sf_None of
1020 True -> return $ tcg_env { tcg_imports = wiped_trust }
1021 False -> return tcg_env
1022
1023 where
1024 wiped_trust = (tcg_imports tcg_env) { imp_trust_pkgs = [] }
1025 pprMod = ppr $ moduleName $ tcg_mod tcg_env
1026 whyUnsafe' df = vcat [ quotes pprMod <+> text "has been inferred as unsafe!"
1027 , text "Reason:"
1028 , nest 4 $ (vcat $ badFlags df) $+$
1029 (vcat $ pprErrMsgBagWithLoc whyUnsafe)
1030 ]
1031 badFlags df = concat $ map (badFlag df) unsafeFlagsForInfer
1032 badFlag df (str,loc,on,_)
1033 | on df = [mkLocMessage SevOutput (loc df) $
1034 text str <+> text "is not allowed in Safe Haskell"]
1035 | otherwise = []
1036
1037 -- | Figure out the final correct safe haskell mode
1038 hscGetSafeMode :: TcGblEnv -> Hsc SafeHaskellMode
1039 hscGetSafeMode tcg_env = do
1040 dflags <- getDynFlags
1041 liftIO $ finalSafeMode dflags tcg_env
1042
1043 --------------------------------------------------------------
1044 -- Simplifiers
1045 --------------------------------------------------------------
1046
1047 hscSimplify :: HscEnv -> ModGuts -> IO ModGuts
1048 hscSimplify hsc_env modguts = runHsc hsc_env $ hscSimplify' modguts
1049
1050 hscSimplify' :: ModGuts -> Hsc ModGuts
1051 hscSimplify' ds_result = do
1052 hsc_env <- getHscEnv
1053 {-# SCC "Core2Core" #-}
1054 liftIO $ core2core hsc_env ds_result
1055
1056 --------------------------------------------------------------
1057 -- Interface generators
1058 --------------------------------------------------------------
1059
1060 hscSimpleIface :: HscEnv
1061 -> TcGblEnv
1062 -> Maybe Fingerprint
1063 -> IO (ModIface, Bool, ModDetails)
1064 hscSimpleIface hsc_env tc_result mb_old_iface
1065 = runHsc hsc_env $ hscSimpleIface' tc_result mb_old_iface
1066
1067 hscSimpleIface' :: TcGblEnv
1068 -> Maybe Fingerprint
1069 -> Hsc (ModIface, Bool, ModDetails)
1070 hscSimpleIface' tc_result mb_old_iface = do
1071 hsc_env <- getHscEnv
1072 details <- liftIO $ mkBootModDetailsTc hsc_env tc_result
1073 safe_mode <- hscGetSafeMode tc_result
1074 (new_iface, no_change)
1075 <- {-# SCC "MkFinalIface" #-}
1076 ioMsgMaybe $
1077 mkIfaceTc hsc_env mb_old_iface safe_mode details tc_result
1078 -- And the answer is ...
1079 liftIO $ dumpIfaceStats hsc_env
1080 return (new_iface, no_change, details)
1081
1082 hscNormalIface :: HscEnv
1083 -> ModGuts
1084 -> Maybe Fingerprint
1085 -> IO (ModIface, Bool, ModDetails, CgGuts)
1086 hscNormalIface hsc_env simpl_result mb_old_iface =
1087 runHsc hsc_env $ hscNormalIface' simpl_result mb_old_iface
1088
1089 hscNormalIface' :: ModGuts
1090 -> Maybe Fingerprint
1091 -> Hsc (ModIface, Bool, ModDetails, CgGuts)
1092 hscNormalIface' simpl_result mb_old_iface = do
1093 hsc_env <- getHscEnv
1094 (cg_guts, details) <- {-# SCC "CoreTidy" #-}
1095 liftIO $ tidyProgram hsc_env simpl_result
1096
1097 -- BUILD THE NEW ModIface and ModDetails
1098 -- and emit external core if necessary
1099 -- This has to happen *after* code gen so that the back-end
1100 -- info has been set. Not yet clear if it matters waiting
1101 -- until after code output
1102 (new_iface, no_change)
1103 <- {-# SCC "MkFinalIface" #-}
1104 ioMsgMaybe $
1105 mkIface hsc_env mb_old_iface details simpl_result
1106
1107 liftIO $ dumpIfaceStats hsc_env
1108
1109 -- Return the prepared code.
1110 return (new_iface, no_change, details, cg_guts)
1111
1112 --------------------------------------------------------------
1113 -- BackEnd combinators
1114 --------------------------------------------------------------
1115
1116 hscWriteIface :: DynFlags -> ModIface -> Bool -> ModSummary -> IO ()
1117 hscWriteIface dflags iface no_change mod_summary = do
1118 let ifaceFile = ml_hi_file (ms_location mod_summary)
1119 unless no_change $
1120 {-# SCC "writeIface" #-}
1121 writeIfaceFile dflags ifaceFile iface
1122 whenGeneratingDynamicToo dflags $ do
1123 -- TODO: We should do a no_change check for the dynamic
1124 -- interface file too
1125 -- TODO: Should handle the dynamic hi filename properly
1126 let dynIfaceFile = replaceExtension ifaceFile (dynHiSuf dflags)
1127 dynIfaceFile' = addBootSuffix_maybe (mi_boot iface) dynIfaceFile
1128 dynDflags = dynamicTooMkDynamicDynFlags dflags
1129 writeIfaceFile dynDflags dynIfaceFile' iface
1130
1131 -- | Compile to hard-code.
1132 hscGenHardCode :: HscEnv -> CgGuts -> ModSummary -> FilePath
1133 -> IO (FilePath, Maybe FilePath) -- ^ @Just f@ <=> _stub.c is f
1134 hscGenHardCode hsc_env cgguts mod_summary output_filename = do
1135 let CgGuts{ -- This is the last use of the ModGuts in a compilation.
1136 -- From now on, we just use the bits we need.
1137 cg_module = this_mod,
1138 cg_binds = core_binds,
1139 cg_tycons = tycons,
1140 cg_foreign = foreign_stubs0,
1141 cg_dep_pkgs = dependencies,
1142 cg_hpc_info = hpc_info } = cgguts
1143 dflags = hsc_dflags hsc_env
1144 location = ms_location mod_summary
1145 data_tycons = filter isDataTyCon tycons
1146 -- cg_tycons includes newtypes, for the benefit of External Core,
1147 -- but we don't generate any code for newtypes
1148
1149 -------------------
1150 -- PREPARE FOR CODE GENERATION
1151 -- Do saturation and convert to A-normal form
1152 prepd_binds <- {-# SCC "CorePrep" #-}
1153 corePrepPgm dflags hsc_env core_binds data_tycons ;
1154 ----------------- Convert to STG ------------------
1155 (stg_binds, cost_centre_info)
1156 <- {-# SCC "CoreToStg" #-}
1157 myCoreToStg dflags this_mod prepd_binds
1158
1159 let prof_init = profilingInitCode this_mod cost_centre_info
1160 foreign_stubs = foreign_stubs0 `appendStubC` prof_init
1161
1162 ------------------ Code generation ------------------
1163
1164 -- The back-end is streamed: each top-level function goes
1165 -- from Stg all the way to asm before dealing with the next
1166 -- top-level function, so showPass isn't very useful here.
1167 -- Hence we have one showPass for the whole backend, the
1168 -- next showPass after this will be "Assembler".
1169 showPass dflags "CodeGen"
1170
1171 cmms <- {-# SCC "StgCmm" #-}
1172 doCodeGen hsc_env this_mod data_tycons
1173 cost_centre_info
1174 stg_binds hpc_info
1175
1176 ------------------ Code output -----------------------
1177 rawcmms0 <- {-# SCC "cmmToRawCmm" #-}
1178 cmmToRawCmm dflags cmms
1179
1180 let dump a = do dumpIfSet_dyn dflags Opt_D_dump_cmm_raw "Raw Cmm"
1181 (ppr a)
1182 return a
1183 rawcmms1 = Stream.mapM dump rawcmms0
1184
1185 (output_filename, (_stub_h_exists, stub_c_exists))
1186 <- {-# SCC "codeOutput" #-}
1187 codeOutput dflags this_mod output_filename location
1188 foreign_stubs dependencies rawcmms1
1189 return (output_filename, stub_c_exists)
1190
1191
1192 hscInteractive :: HscEnv
1193 -> CgGuts
1194 -> ModSummary
1195 -> IO (Maybe FilePath, CompiledByteCode, ModBreaks)
1196 #ifdef GHCI
1197 hscInteractive hsc_env cgguts mod_summary = do
1198 let dflags = hsc_dflags hsc_env
1199 let CgGuts{ -- This is the last use of the ModGuts in a compilation.
1200 -- From now on, we just use the bits we need.
1201 cg_module = this_mod,
1202 cg_binds = core_binds,
1203 cg_tycons = tycons,
1204 cg_foreign = foreign_stubs,
1205 cg_modBreaks = mod_breaks } = cgguts
1206
1207 location = ms_location mod_summary
1208 data_tycons = filter isDataTyCon tycons
1209 -- cg_tycons includes newtypes, for the benefit of External Core,
1210 -- but we don't generate any code for newtypes
1211
1212 -------------------
1213 -- PREPARE FOR CODE GENERATION
1214 -- Do saturation and convert to A-normal form
1215 prepd_binds <- {-# SCC "CorePrep" #-}
1216 corePrepPgm dflags hsc_env core_binds data_tycons
1217 ----------------- Generate byte code ------------------
1218 comp_bc <- byteCodeGen dflags this_mod prepd_binds data_tycons mod_breaks
1219 ------------------ Create f-x-dynamic C-side stuff ---
1220 (_istub_h_exists, istub_c_exists)
1221 <- outputForeignStubs dflags this_mod location foreign_stubs
1222 return (istub_c_exists, comp_bc, mod_breaks)
1223 #else
1224 hscInteractive _ _ = panic "GHC not compiled with interpreter"
1225 #endif
1226
1227 ------------------------------
1228
1229 hscCompileCmmFile :: HscEnv -> FilePath -> FilePath -> IO ()
1230 hscCompileCmmFile hsc_env filename output_filename = runHsc hsc_env $ do
1231 let dflags = hsc_dflags hsc_env
1232 cmm <- ioMsgMaybe $ parseCmmFile dflags filename
1233 liftIO $ do
1234 us <- mkSplitUniqSupply 'S'
1235 let initTopSRT = initUs_ us emptySRT
1236 dumpIfSet_dyn dflags Opt_D_dump_cmm "Parsed Cmm" (ppr cmm)
1237 (_, cmmgroup) <- cmmPipeline hsc_env initTopSRT cmm
1238 rawCmms <- cmmToRawCmm dflags (Stream.yield cmmgroup)
1239 _ <- codeOutput dflags no_mod output_filename no_loc NoStubs [] rawCmms
1240 return ()
1241 where
1242 no_mod = panic "hscCmmFile: no_mod"
1243 no_loc = ModLocation{ ml_hs_file = Just filename,
1244 ml_hi_file = panic "hscCmmFile: no hi file",
1245 ml_obj_file = panic "hscCmmFile: no obj file" }
1246
1247 -------------------- Stuff for new code gen ---------------------
1248
1249 doCodeGen :: HscEnv -> Module -> [TyCon]
1250 -> CollectedCCs
1251 -> [StgBinding]
1252 -> HpcInfo
1253 -> IO (Stream IO CmmGroup ())
1254 -- Note we produce a 'Stream' of CmmGroups, so that the
1255 -- backend can be run incrementally. Otherwise it generates all
1256 -- the C-- up front, which has a significant space cost.
1257 doCodeGen hsc_env this_mod data_tycons
1258 cost_centre_info stg_binds hpc_info = do
1259 let dflags = hsc_dflags hsc_env
1260
1261 let cmm_stream :: Stream IO CmmGroup ()
1262 cmm_stream = {-# SCC "StgCmm" #-}
1263 StgCmm.codeGen dflags this_mod data_tycons
1264 cost_centre_info stg_binds hpc_info
1265
1266 -- codegen consumes a stream of CmmGroup, and produces a new
1267 -- stream of CmmGroup (not necessarily synchronised: one
1268 -- CmmGroup on input may produce many CmmGroups on output due
1269 -- to proc-point splitting).
1270
1271 let dump1 a = do dumpIfSet_dyn dflags Opt_D_dump_cmm
1272 "Cmm produced by new codegen" (ppr a)
1273 return a
1274
1275 ppr_stream1 = Stream.mapM dump1 cmm_stream
1276
1277 -- We are building a single SRT for the entire module, so
1278 -- we must thread it through all the procedures as we cps-convert them.
1279 us <- mkSplitUniqSupply 'S'
1280
1281 -- When splitting, we generate one SRT per split chunk, otherwise
1282 -- we generate one SRT for the whole module.
1283 let
1284 pipeline_stream
1285 | gopt Opt_SplitObjs dflags
1286 = {-# SCC "cmmPipeline" #-}
1287 let run_pipeline us cmmgroup = do
1288 let (topSRT', us') = initUs us emptySRT
1289 (topSRT, cmmgroup) <- cmmPipeline hsc_env topSRT' cmmgroup
1290 let srt | isEmptySRT topSRT = []
1291 | otherwise = srtToData topSRT
1292 return (us', srt ++ cmmgroup)
1293
1294 in do _ <- Stream.mapAccumL run_pipeline us ppr_stream1
1295 return ()
1296
1297 | otherwise
1298 = {-# SCC "cmmPipeline" #-}
1299 let initTopSRT = initUs_ us emptySRT
1300 run_pipeline = cmmPipeline hsc_env
1301 in do topSRT <- Stream.mapAccumL run_pipeline initTopSRT ppr_stream1
1302 Stream.yield (srtToData topSRT)
1303
1304 let
1305 dump2 a = do dumpIfSet_dyn dflags Opt_D_dump_cmm "Output Cmm" $ ppr a
1306 return a
1307
1308 ppr_stream2 = Stream.mapM dump2 pipeline_stream
1309
1310 return ppr_stream2
1311
1312
1313
1314 myCoreToStg :: DynFlags -> Module -> CoreProgram
1315 -> IO ( [StgBinding] -- output program
1316 , CollectedCCs) -- cost centre info (declared and used)
1317 myCoreToStg dflags this_mod prepd_binds = do
1318 stg_binds
1319 <- {-# SCC "Core2Stg" #-}
1320 coreToStg dflags this_mod prepd_binds
1321
1322 (stg_binds2, cost_centre_info)
1323 <- {-# SCC "Stg2Stg" #-}
1324 stg2stg dflags this_mod stg_binds
1325
1326 return (stg_binds2, cost_centre_info)
1327
1328
1329 {- **********************************************************************
1330 %* *
1331 \subsection{Compiling a do-statement}
1332 %* *
1333 %********************************************************************* -}
1334
1335 {-
1336 When the UnlinkedBCOExpr is linked you get an HValue of type *IO [HValue]* When
1337 you run it you get a list of HValues that should be the same length as the list
1338 of names; add them to the ClosureEnv.
1339
1340 A naked expression returns a singleton Name [it]. The stmt is lifted into the
1341 IO monad as explained in Note [Interactively-bound Ids in GHCi] in HscTypes
1342 -}
1343
1344 #ifdef GHCI
1345 -- | Compile a stmt all the way to an HValue, but don't run it
1346 --
1347 -- We return Nothing to indicate an empty statement (or comment only), not a
1348 -- parse error.
1349 hscStmt :: HscEnv -> String -> IO (Maybe ([Id], IO [HValue], FixityEnv))
1350 hscStmt hsc_env stmt = hscStmtWithLocation hsc_env stmt "<interactive>" 1
1351
1352 -- | Compile a stmt all the way to an HValue, but don't run it
1353 --
1354 -- We return Nothing to indicate an empty statement (or comment only), not a
1355 -- parse error.
1356 hscStmtWithLocation :: HscEnv
1357 -> String -- ^ The statement
1358 -> String -- ^ The source
1359 -> Int -- ^ Starting line
1360 -> IO (Maybe ([Id], IO [HValue], FixityEnv))
1361 hscStmtWithLocation hsc_env0 stmt source linenumber =
1362 runInteractiveHsc hsc_env0 $ do
1363 maybe_stmt <- hscParseStmtWithLocation source linenumber stmt
1364 case maybe_stmt of
1365 Nothing -> return Nothing
1366
1367 Just parsed_stmt -> do
1368 -- Rename and typecheck it
1369 hsc_env <- getHscEnv
1370 (ids, tc_expr, fix_env) <- ioMsgMaybe $ tcRnStmt hsc_env parsed_stmt
1371
1372 -- Desugar it
1373 ds_expr <- ioMsgMaybe $ deSugarExpr hsc_env tc_expr
1374 liftIO (lintInteractiveExpr "desugar expression" hsc_env ds_expr)
1375 handleWarnings
1376
1377 -- Then code-gen, and link it
1378 -- It's important NOT to have package 'interactive' as thisPackageKey
1379 -- for linking, else we try to link 'main' and can't find it.
1380 -- Whereas the linker already knows to ignore 'interactive'
1381 let src_span = srcLocSpan interactiveSrcLoc
1382 hval <- liftIO $ hscCompileCoreExpr hsc_env src_span ds_expr
1383 let hval_io = unsafeCoerce# hval :: IO [HValue]
1384
1385 return $ Just (ids, hval_io, fix_env)
1386
1387 -- | Compile a decls
1388 hscDecls :: HscEnv
1389 -> String -- ^ The statement
1390 -> IO ([TyThing], InteractiveContext)
1391 hscDecls hsc_env str = hscDeclsWithLocation hsc_env str "<interactive>" 1
1392
1393 -- | Compile a decls
1394 hscDeclsWithLocation :: HscEnv
1395 -> String -- ^ The statement
1396 -> String -- ^ The source
1397 -> Int -- ^ Starting line
1398 -> IO ([TyThing], InteractiveContext)
1399 hscDeclsWithLocation hsc_env0 str source linenumber =
1400 runInteractiveHsc hsc_env0 $ do
1401 L _ (HsModule{ hsmodDecls = decls }) <-
1402 hscParseThingWithLocation source linenumber parseModule str
1403
1404 {- Rename and typecheck it -}
1405 hsc_env <- getHscEnv
1406 tc_gblenv <- ioMsgMaybe $ tcRnDeclsi hsc_env decls
1407
1408 {- Grab the new instances -}
1409 -- We grab the whole environment because of the overlapping that may have
1410 -- been done. See the notes at the definition of InteractiveContext
1411 -- (ic_instances) for more details.
1412 let finsts = tcg_fam_insts tc_gblenv
1413 insts = tcg_insts tc_gblenv
1414
1415 let defaults = tcg_default tc_gblenv
1416
1417 {- Desugar it -}
1418 -- We use a basically null location for iNTERACTIVE
1419 let iNTERACTIVELoc = ModLocation{ ml_hs_file = Nothing,
1420 ml_hi_file = panic "hsDeclsWithLocation:ml_hi_file",
1421 ml_obj_file = panic "hsDeclsWithLocation:ml_hi_file"}
1422 ds_result <- hscDesugar' iNTERACTIVELoc tc_gblenv
1423
1424 {- Simplify -}
1425 simpl_mg <- liftIO $ hscSimplify hsc_env ds_result
1426
1427 {- Tidy -}
1428 (tidy_cg, _mod_details) <- liftIO $ tidyProgram hsc_env simpl_mg
1429
1430 let dflags = hsc_dflags hsc_env
1431 !CgGuts{ cg_module = this_mod,
1432 cg_binds = core_binds,
1433 cg_tycons = tycons,
1434 cg_modBreaks = mod_breaks } = tidy_cg
1435 data_tycons = filter isDataTyCon tycons
1436
1437 {- Prepare For Code Generation -}
1438 -- Do saturation and convert to A-normal form
1439 prepd_binds <- {-# SCC "CorePrep" #-}
1440 liftIO $ corePrepPgm dflags hsc_env core_binds data_tycons
1441
1442 {- Generate byte code -}
1443 cbc <- liftIO $ byteCodeGen dflags this_mod
1444 prepd_binds data_tycons mod_breaks
1445
1446 let src_span = srcLocSpan interactiveSrcLoc
1447 liftIO $ linkDecls hsc_env src_span cbc
1448
1449 let tcs = filterOut isImplicitTyCon (mg_tcs simpl_mg)
1450
1451 ext_ids = [ id | id <- bindersOfBinds core_binds
1452 , isExternalName (idName id)
1453 , not (isDFunId id || isImplicitId id) ]
1454 -- We only need to keep around the external bindings
1455 -- (as decided by TidyPgm), since those are the only ones
1456 -- that might be referenced elsewhere.
1457 -- The DFunIds are in 'insts' (see Note [ic_tythings] in HscTypes
1458 -- Implicit Ids are implicit in tcs
1459
1460 tythings = map AnId ext_ids ++ map ATyCon tcs
1461
1462 let icontext = hsc_IC hsc_env
1463 ictxt1 = extendInteractiveContext icontext tythings
1464 ictxt = ictxt1 { ic_instances = (insts, finsts)
1465 , ic_default = defaults }
1466
1467 return (tythings, ictxt)
1468
1469 hscImport :: HscEnv -> String -> IO (ImportDecl RdrName)
1470 hscImport hsc_env str = runInteractiveHsc hsc_env $ do
1471 (L _ (HsModule{hsmodImports=is})) <-
1472 hscParseThing parseModule str
1473 case is of
1474 [i] -> return (unLoc i)
1475 _ -> liftIO $ throwOneError $
1476 mkPlainErrMsg (hsc_dflags hsc_env) noSrcSpan $
1477 ptext (sLit "parse error in import declaration")
1478
1479 -- | Typecheck an expression (but don't run it)
1480 -- Returns its most general type
1481 hscTcExpr :: HscEnv
1482 -> String -- ^ The expression
1483 -> IO Type
1484 hscTcExpr hsc_env0 expr = runInteractiveHsc hsc_env0 $ do
1485 hsc_env <- getHscEnv
1486 maybe_stmt <- hscParseStmt expr
1487 case maybe_stmt of
1488 Just (L _ (BodyStmt expr _ _ _)) ->
1489 ioMsgMaybe $ tcRnExpr hsc_env expr
1490 _ ->
1491 throwErrors $ unitBag $ mkPlainErrMsg (hsc_dflags hsc_env) noSrcSpan
1492 (text "not an expression:" <+> quotes (text expr))
1493
1494 -- | Find the kind of a type
1495 -- Currently this does *not* generalise the kinds of the type
1496 hscKcType
1497 :: HscEnv
1498 -> Bool -- ^ Normalise the type
1499 -> String -- ^ The type as a string
1500 -> IO (Type, Kind) -- ^ Resulting type (possibly normalised) and kind
1501 hscKcType hsc_env0 normalise str = runInteractiveHsc hsc_env0 $ do
1502 hsc_env <- getHscEnv
1503 ty <- hscParseType str
1504 ioMsgMaybe $ tcRnType hsc_env normalise ty
1505
1506 hscParseStmt :: String -> Hsc (Maybe (GhciLStmt RdrName))
1507 hscParseStmt = hscParseThing parseStmt
1508
1509 hscParseStmtWithLocation :: String -> Int -> String
1510 -> Hsc (Maybe (GhciLStmt RdrName))
1511 hscParseStmtWithLocation source linenumber stmt =
1512 hscParseThingWithLocation source linenumber parseStmt stmt
1513
1514 hscParseType :: String -> Hsc (LHsType RdrName)
1515 hscParseType = hscParseThing parseType
1516 #endif
1517
1518 hscParseIdentifier :: HscEnv -> String -> IO (Located RdrName)
1519 hscParseIdentifier hsc_env str =
1520 runInteractiveHsc hsc_env $ hscParseThing parseIdentifier str
1521
1522 hscParseThing :: (Outputable thing) => Lexer.P thing -> String -> Hsc thing
1523 hscParseThing = hscParseThingWithLocation "<interactive>" 1
1524
1525 hscParseThingWithLocation :: (Outputable thing) => String -> Int
1526 -> Lexer.P thing -> String -> Hsc thing
1527 hscParseThingWithLocation source linenumber parser str
1528 = {-# SCC "Parser" #-} do
1529 dflags <- getDynFlags
1530 liftIO $ showPass dflags "Parser"
1531
1532 let buf = stringToStringBuffer str
1533 loc = mkRealSrcLoc (fsLit source) linenumber 1
1534
1535 case unP parser (mkPState dflags buf loc) of
1536 PFailed span err -> do
1537 let msg = mkPlainErrMsg dflags span err
1538 throwErrors $ unitBag msg
1539
1540 POk pst thing -> do
1541 logWarningsReportErrors (getMessages pst)
1542 liftIO $ dumpIfSet_dyn dflags Opt_D_dump_parsed "Parser" (ppr thing)
1543 return thing
1544
1545 hscCompileCore :: HscEnv -> Bool -> SafeHaskellMode -> ModSummary
1546 -> CoreProgram -> FilePath -> IO ()
1547 hscCompileCore hsc_env simplify safe_mode mod_summary binds output_filename
1548 = runHsc hsc_env $ do
1549 guts <- maybe_simplify (mkModGuts (ms_mod mod_summary) safe_mode binds)
1550 (iface, changed, _details, cgguts) <- hscNormalIface' guts Nothing
1551 liftIO $ hscWriteIface (hsc_dflags hsc_env) iface changed mod_summary
1552 _ <- liftIO $ hscGenHardCode hsc_env cgguts mod_summary output_filename
1553 return ()
1554
1555 where
1556 maybe_simplify mod_guts | simplify = hscSimplify' mod_guts
1557 | otherwise = return mod_guts
1558
1559 -- Makes a "vanilla" ModGuts.
1560 mkModGuts :: Module -> SafeHaskellMode -> CoreProgram -> ModGuts
1561 mkModGuts mod safe binds =
1562 ModGuts {
1563 mg_module = mod,
1564 mg_boot = False,
1565 mg_exports = [],
1566 mg_deps = noDependencies,
1567 mg_dir_imps = emptyModuleEnv,
1568 mg_used_names = emptyNameSet,
1569 mg_used_th = False,
1570 mg_rdr_env = emptyGlobalRdrEnv,
1571 mg_fix_env = emptyFixityEnv,
1572 mg_tcs = [],
1573 mg_insts = [],
1574 mg_fam_insts = [],
1575 mg_patsyns = [],
1576 mg_rules = [],
1577 mg_vect_decls = [],
1578 mg_binds = binds,
1579 mg_foreign = NoStubs,
1580 mg_warns = NoWarnings,
1581 mg_anns = [],
1582 mg_hpc_info = emptyHpcInfo False,
1583 mg_modBreaks = emptyModBreaks,
1584 mg_vect_info = noVectInfo,
1585 mg_inst_env = emptyInstEnv,
1586 mg_fam_inst_env = emptyFamInstEnv,
1587 mg_safe_haskell = safe,
1588 mg_trust_pkg = False,
1589 mg_dependent_files = []
1590 }
1591
1592
1593 {- **********************************************************************
1594 %* *
1595 Desugar, simplify, convert to bytecode, and link an expression
1596 %* *
1597 %********************************************************************* -}
1598
1599 #ifdef GHCI
1600 hscCompileCoreExpr :: HscEnv -> SrcSpan -> CoreExpr -> IO HValue
1601 hscCompileCoreExpr hsc_env =
1602 lookupHook hscCompileCoreExprHook hscCompileCoreExpr' (hsc_dflags hsc_env) hsc_env
1603
1604 hscCompileCoreExpr' :: HscEnv -> SrcSpan -> CoreExpr -> IO HValue
1605 hscCompileCoreExpr' hsc_env srcspan ds_expr
1606 | rtsIsProfiled
1607 = throwIO (InstallationError "You can't call hscCompileCoreExpr in a profiled compiler")
1608 -- Otherwise you get a seg-fault when you run it
1609
1610 | otherwise
1611 = do { let dflags = hsc_dflags hsc_env
1612
1613 {- Simplify it -}
1614 ; simpl_expr <- simplifyExpr dflags ds_expr
1615
1616 {- Tidy it (temporary, until coreSat does cloning) -}
1617 ; let tidy_expr = tidyExpr emptyTidyEnv simpl_expr
1618
1619 {- Prepare for codegen -}
1620 ; prepd_expr <- corePrepExpr dflags hsc_env tidy_expr
1621
1622 {- Lint if necessary -}
1623 ; lintInteractiveExpr "hscCompileExpr" hsc_env prepd_expr
1624
1625 {- Convert to BCOs -}
1626 ; bcos <- coreExprToBCOs dflags (icInteractiveModule (hsc_IC hsc_env)) prepd_expr
1627
1628 {- link it -}
1629 ; hval <- linkExpr hsc_env srcspan bcos
1630
1631 ; return hval }
1632 #endif
1633
1634
1635 {- **********************************************************************
1636 %* *
1637 Statistics on reading interfaces
1638 %* *
1639 %********************************************************************* -}
1640
1641 dumpIfaceStats :: HscEnv -> IO ()
1642 dumpIfaceStats hsc_env = do
1643 eps <- readIORef (hsc_EPS hsc_env)
1644 dumpIfSet dflags (dump_if_trace || dump_rn_stats)
1645 "Interface statistics"
1646 (ifaceStats eps)
1647 where
1648 dflags = hsc_dflags hsc_env
1649 dump_rn_stats = dopt Opt_D_dump_rn_stats dflags
1650 dump_if_trace = dopt Opt_D_dump_if_trace dflags
1651
1652
1653 {- **********************************************************************
1654 %* *
1655 Progress Messages: Module i of n
1656 %* *
1657 %********************************************************************* -}
1658
1659 showModuleIndex :: (Int, Int) -> String
1660 showModuleIndex (i,n) = "[" ++ padded ++ " of " ++ n_str ++ "] "
1661 where
1662 n_str = show n
1663 i_str = show i
1664 padded = replicate (length n_str - length i_str) ' ' ++ i_str