%
-% (c) The University of Glasgow, 2000
+% (c) The University of Glasgow, 2001
%
-\section[CmLink]{Linker for GHCI}
+\section[CmLink]{The compilation manager's linker}
\begin{code}
-module CmLink ( Linkable(..), Unlinked(..),
- filterModuleLinkables,
- modname_of_linkable, is_package_linkable,
- LinkResult(..),
- link,
- PersistentLinkerState{-abstractly!-}, emptyPLS )
-where
+module CmLink (
+ LinkResult(..), link, unload,
+ filterModuleLinkables,
+ findModuleLinkable_maybe,
+
+ PersistentLinkerState{-abstractly!-}, emptyPLS,
+
+#ifdef GHCI
+ delListFromClosureEnv,
+ addListToClosureEnv,
+ linkExpr
+#endif
+ ) where
+
+
+#ifdef GHCI
+import ByteCodeLink ( linkIModules, linkIExpr )
+#endif
import Interpreter
-import CmStaticInfo ( PackageConfigInfo )
-import Module ( ModuleName, PackageName )
-import Outputable ( SDoc )
-import Digraph ( SCC(..), flattenSCC, flattenSCCs )
+import DriverPipeline
+import CmTypes
+import HscTypes ( GhciMode(..) )
+import Name ( Name )
+import Module ( ModuleName )
+import FiniteMap
import Outputable
-import Panic ( panic )
+import ErrUtils ( showPass )
+import CmdLineOpts ( DynFlags(..) )
+import Util
+
+#ifdef GHCI
+import Exception ( block )
+#endif
+
+import IOExts
+import List
+import Monad
+import IO
#include "HsVersions.h"
-\end{code}
-\begin{code}
-data PersistentLinkerState
+-- ---------------------------------------------------------------------------
+-- The Linker's state
+
+-- The PersistentLinkerState maps Names to actual closures (for
+-- interpreted code only), for use during linking.
+
+data PersistentLinkerState
= PersistentLinkerState {
#ifdef GHCI
-- Current global mapping from RdrNames to closure addresses
closure_env :: ClosureEnv,
- -- the current global mapping from RdrNames of DataCons to
+ -- the current global mapping from RdrNames of DataCons to
-- info table addresses.
-- When a new Unlinked is linked into the running image, or an existing
-- module in the image is replaced, the itbl_env must be updated
-- appropriately.
- itbl_env :: ItblEnv
+ itbl_env :: ItblEnv,
+
+ -- the currently loaded interpreted modules
+ bcos_loaded :: [Linkable]
- -- notionally here, but really lives in the C part of the linker:
- -- object_symtab :: FiniteMap String Addr
#else
dummy :: () -- sigh, can't have an empty record
#endif
}
-data LinkResult
- = LinkOK PersistentLinkerState
- | LinkErrs PersistentLinkerState [SDoc]
+emptyPLS :: IO PersistentLinkerState
+#ifdef GHCI
+emptyPLS = return (PersistentLinkerState { closure_env = emptyFM,
+ itbl_env = emptyFM,
+ bcos_loaded = [] })
+#else
+emptyPLS = return (PersistentLinkerState {dummy=()})
+#endif
+
+-- We also keep track of which object modules are currently loaded
+-- into the dynamic linker, so that we can unload them again later.
+--
+-- This state *must* match the actual state of the dyanmic linker at
+-- all times, which is why we keep it private here and don't
+-- put it in the PersistentLinkerState.
+--
+GLOBAL_VAR(v_ObjectsLoaded, [], [Linkable])
-data Unlinked
- = DotO FilePath
- | DotA FilePath
- | DotDLL FilePath
- | Trees [UnlinkedIBind] ItblEnv -- bunch of interpretable bindings, +
- -- a mapping from DataCons to their itbls
-instance Outputable Unlinked where
- ppr (DotO path) = text "DotO" <+> text path
- ppr (DotA path) = text "DotA" <+> text path
- ppr (DotDLL path) = text "DotDLL" <+> text path
- ppr (Trees binds _) = text "Trees" <+> ppr binds
+-- ---------------------------------------------------------------------------
+-- Utils
+findModuleLinkable_maybe :: [Linkable] -> ModuleName -> Maybe Linkable
+findModuleLinkable_maybe lis mod
+ = case [LM time nm us | LM time nm us <- lis, nm == mod] of
+ [] -> Nothing
+ [li] -> Just li
+ many -> pprPanic "findModuleLinkable" (ppr mod)
+
+filterModuleLinkables :: (ModuleName -> Bool) -> [Linkable] -> [Linkable]
+filterModuleLinkables p [] = []
+filterModuleLinkables p (li:lis)
+ = case li of
+ LM _ modnm _ -> if p modnm then retain else dump
+ where
+ dump = filterModuleLinkables p lis
+ retain = li : dump
-isObject (DotO _) = True
-isObject (DotA _) = True
-isObject (DotDLL _) = True
-isObject _ = False
+linkableInSet :: Linkable -> [Linkable] -> Bool
+linkableInSet l objs_loaded =
+ case findModuleLinkable_maybe objs_loaded (linkableModName l) of
+ Nothing -> False
+ Just m -> linkableTime l == linkableTime m
-nameOfObject (DotO fn) = fn
-nameOfObject (DotA fn) = fn
-nameOfObject (DotDLL fn) = fn
+-- These two are used to add/remove entries from the closure env for
+-- new bindings made at the prompt.
+#ifdef GHCI
+delListFromClosureEnv :: PersistentLinkerState -> [Name]
+ -> IO PersistentLinkerState
+delListFromClosureEnv pls names
+ = return pls{ closure_env = delListFromFM (closure_env pls) names }
-isInterpretable (Trees _ _) = True
-isInterpretable _ = False
+addListToClosureEnv :: PersistentLinkerState -> [(Name,HValue)]
+ -> IO PersistentLinkerState
+addListToClosureEnv pls new_bindings
+ = return pls{ closure_env = addListToFM (closure_env pls) new_bindings }
+#endif
-data Linkable
- = LM ModuleName [Unlinked]
- | LP PackageName
+-- ---------------------------------------------------------------------------
+-- Unloading old objects ready for a new compilation sweep.
+--
+-- The compilation manager provides us with a list of linkables that it
+-- considers "stable", i.e. won't be recompiled this time around. For
+-- each of the modules current linked in memory,
+--
+-- * if the linkable is stable (and it's the same one - the
+-- user may have recompiled the module on the side), we keep it,
+--
+-- * otherwise, we unload it.
+--
+-- * we also implicitly unload all temporary bindings at this point.
-instance Outputable Linkable where
- ppr (LM mod_nm unlinkeds) = text "LinkableM" <+> ppr mod_nm <+> ppr unlinkeds
- ppr (LP package_nm) = text "LinkableP" <+> ptext package_nm
+unload :: GhciMode
+ -> DynFlags
+ -> [Linkable] -- stable linkables
+ -> PersistentLinkerState
+ -> IO PersistentLinkerState
+
+unload Batch dflags linkables pls = return pls
-emptyPLS :: IO PersistentLinkerState
#ifdef GHCI
-emptyPLS = return (PersistentLinkerState { closure_env = emptyFM,
- itbl_env = emptyFM })
+unload Interactive dflags linkables pls
+ = block $ do -- block, so we're safe from Ctrl-C in here
+ objs_loaded <- readIORef v_ObjectsLoaded
+ objs_loaded' <- filterM (maybeUnload objs_to_keep) objs_loaded
+ writeIORef v_ObjectsLoaded objs_loaded'
+
+ bcos_loaded' <- filterM (maybeUnload bcos_to_keep) (bcos_loaded pls)
+
+ let objs_retained = map linkableModName objs_loaded'
+ bcos_retained = map linkableModName bcos_loaded'
+ itbl_env' = filterNameMap bcos_retained (itbl_env pls)
+ closure_env' = filterNameMap bcos_retained (closure_env pls)
+
+ let verb = verbosity dflags
+ when (verb >= 3) $ do
+ hPutStrLn stderr (showSDoc
+ (text "CmLink.unload: retaining objs" <+> ppr objs_retained))
+ hPutStrLn stderr (showSDoc
+ (text "CmLink.unload: retaining bcos" <+> ppr bcos_retained))
+
+ return pls{ itbl_env = itbl_env',
+ closure_env = closure_env',
+ bcos_loaded = bcos_loaded' }
+ where
+ (objs_to_keep, bcos_to_keep) = partition isObjectLinkable linkables
+
+ maybeUnload :: [Linkable] -> Linkable -> IO Bool
+ maybeUnload keep_linkables l@(LM time mod objs)
+ | linkableInSet l linkables
+ = return True
+ | otherwise
+ = do mapM unloadObj [ f | DotO f <- objs ]
+ return False
#else
-emptyPLS = return (PersistentLinkerState {})
+unload Interactive dflags linkables pls = panic "CmLink.unload: no interpreter"
#endif
-\end{code}
-\begin{code}
--- The first arg is supposed to be DriverPipeline.doLink.
--- Passed in here to avoid a hard-to-avoid circular dependency
--- between CmLink and DriverPipeline. Same deal as with
--- CmSummarise.summarise.
-link :: ([String] -> IO ())
- -> Bool -- was the upsweep completely successful?
- -> PackageConfigInfo
- -> [SCC Linkable]
- -> PersistentLinkerState
+-----------------------------------------------------------------------------
+-- Linking
+
+data LinkResult
+ = LinkOK PersistentLinkerState
+ | LinkFailed PersistentLinkerState
+
+link :: GhciMode -- interactive or batch
+ -> DynFlags -- dynamic flags
+ -> Bool -- attempt linking in batch mode?
+ -> [Linkable]
+ -> PersistentLinkerState
-> IO LinkResult
-#ifndef GHCI_NOTYET
---link = panic "CmLink.link: not implemented"
-
--- For the moment, in the batch linker, we don't bother to
--- tell doLink which packages to link -- it just tries all that
--- are available.
-link doLink upsweep_complete_success pci groups pls1
- | upsweep_complete_success
- = do putStrLn "Hello from the Linker!"
- putStrLn (showSDoc (vcat (map ppLinkableSCC groups)))
- let o_files = concatMap getOfiles (flattenSCCs groups)
+-- For the moment, in the batch linker, we don't bother to tell doLink
+-- which packages to link -- it just tries all that are available.
+-- batch_attempt_linking should only be *looked at* in batch mode. It
+-- should only be True if the upsweep was successful and someone
+-- exports main, i.e., we have good reason to believe that linking
+-- will succeed.
+
+-- There will be (ToDo: are) two lists passed to link. These
+-- correspond to
+--
+-- 1. The list of all linkables in the current home package. This is
+-- used by the batch linker to link the program, and by the interactive
+-- linker to decide which modules from the previous link it can
+-- throw away.
+-- 2. The list of modules on which we just called "compile". This list
+-- is used by the interactive linker to decide which modules need
+-- to be actually linked this time around (or unlinked and re-linked
+-- if the module was recompiled).
+
+link mode dflags batch_attempt_linking linkables pls1
+ = do let verb = verbosity dflags
+ when (verb >= 3) $ do
+ hPutStrLn stderr "CmLink.link: linkables are ..."
+ hPutStrLn stderr (showSDoc (vcat (map ppr linkables)))
+ res <- link' mode dflags batch_attempt_linking linkables pls1
+ when (verb >= 3) $
+ hPutStrLn stderr "CmLink.link: done"
+ return res
+
+link' Batch dflags batch_attempt_linking linkables pls1
+ | batch_attempt_linking
+ = do let o_files = concatMap getOfiles linkables
+ when (verb >= 1) $
+ hPutStrLn stderr "ghc: linking ..."
+ -- don't showPass in Batch mode; doLink will do that for us.
doLink o_files
- putStrLn "Bye-bye from the Linker!"
+ -- doLink only returns if it succeeds
return (LinkOK pls1)
| otherwise
- = do putStrLn "LINKER: upsweep (partially?) failed; not doing batch linking"
+ = do when (verb >= 3) $ do
+ hPutStrLn stderr "CmLink.link(batch): upsweep (partially) failed OR"
+ hPutStrLn stderr " Main.main not exported; not linking."
return (LinkOK pls1)
where
- getOfiles (LP _) = []
- getOfiles (LM _ us) = map nameOfObject (filter isObject us)
+ verb = verbosity dflags
+ getOfiles (LM _ _ us) = map nameOfObject (filter isObject us)
-
+#ifdef GHCI
+link' Interactive dflags batch_attempt_linking linkables pls
+ = do showPass dflags "Linking"
+ block $ do -- don't want to be interrupted by ^C in here
-ppLinkableSCC :: SCC Linkable -> SDoc
-ppLinkableSCC = ppr . flattenSCC
+ -- Always load objects first. Objects aren't allowed to
+ -- depend on BCOs.
+ let (objs, bcos) = partition isObjectLinkable linkables
-#else
+ objs_loaded <- readIORef v_ObjectsLoaded
+ objs_loaded' <- linkObjs objs objs_loaded
+ writeIORef v_ObjectsLoaded objs_loaded'
+ -- resolve symbols within the object files
+ ok <- resolveObjs
+ -- if resolving failed, unload all our object modules and
+ -- carry on.
+ if (not ok)
+ then do pls <- unload Interactive dflags [] pls
+ return (LinkFailed pls)
+ else do
-link pci [] pls = return (LinkOK pls)
-link pci (groupSCC:groups) pls = do
- let group = flattenSCC groupSCC
- -- the group is either all objects or all interpretable, for now
- if all isObject group
- then do mapM loadObj [ file | DotO file <- group ]
- resolveObjs
- link pci groups pls
- else if all isInterpretable group
- then do (new_closure_env, new_itbl_env) <-
- linkIModules (closure_env pls)
- (itbl_env pls)
- [ trees | Trees trees <- group ]
- link pci groups (PersistentLinkerState{
- closure_env=new_closure_env,
- itbl_env=new_itbl_env})
- else
- return (LinkErrs pls (ptext SLIT("linker: group must contain all objects or all interpreted modules")))
+ -- finally link the interpreted linkables
+ linkBCOs bcos [] pls
#endif
+-----------------------------------------------------------------------------
+-- Linker for interactive mode
-modname_of_linkable (LM nm _) = nm
-modname_of_linkable (LP _) = panic "modname_of_linkable: package"
+#ifdef GHCI
+linkObjs [] objs_loaded = return objs_loaded
+linkObjs (l@(LM _ m uls) : ls) objs_loaded
+ | linkableInSet l objs_loaded = linkObjs ls objs_loaded -- already loaded
+ | otherwise = do mapM_ loadObj [ file | DotO file <- uls ]
+ linkObjs ls (l:objs_loaded)
-is_package_linkable (LP _) = True
-is_package_linkable (LM _ _) = False
+linkBCOs [] ul_trees pls = linkFinish pls ul_trees
+linkBCOs (l@(LM _ m uls) : ls) ul_trees pls
+ | linkableInSet l (bcos_loaded pls)
+ = linkBCOs ls ul_trees pls
+ | otherwise
+ = linkBCOs ls (uls++ul_trees) pls{bcos_loaded = l : bcos_loaded pls}
-filterModuleLinkables :: (ModuleName -> Bool)
- -> [Linkable]
- -> [Linkable]
-filterModuleLinkables p [] = []
-filterModuleLinkables p (li:lis)
- = case li of
- LP _ -> retain
- LM modnm _ -> if p modnm then retain else dump
- where
- dump = filterModuleLinkables p lis
- retain = li : dump
+-- link all the interpreted code in one go.
+linkFinish pls ul_bcos = do
+
+ let stuff = [ (bcos,itbls) | BCOs bcos itbls <- ul_bcos ]
+
+ (ibinds, new_itbl_env, new_closure_env) <-
+ linkIModules (itbl_env pls) (closure_env pls) stuff
+
+ let new_pls = pls { closure_env = new_closure_env,
+ itbl_env = new_itbl_env
+ }
+ return (LinkOK new_pls)
+#endif
+
+-- ---------------------------------------------------------------------------
+-- Link a single expression
+
+#ifdef GHCI
+linkExpr :: PersistentLinkerState -> UnlinkedBCOExpr -> IO HValue
+linkExpr PersistentLinkerState{ itbl_env = ie, closure_env = ce } bcos
+ = linkIExpr ie ce bcos
+#endif
\end{code}
projects / ghc-hetmet.git / blobdiff