Cheng Shao pushed to branch wip/batch-loaddll at Glasgow Haskell Compiler / GHC Commits: 22f896cc by Cheng Shao at 2025-08-21T00:52:46+02:00 ghci: LoadDLL -> LoadDLLs Closes #25407. Co-authored-by: Codex - - - - - d9a2d03b by Cheng Shao at 2025-08-21T00:52:50+02:00 loadPackages': separate downsweep/upsweep - - - - - 8 changed files: - compiler/GHC/Driver/Plugins.hs - compiler/GHC/Linker/Loader.hs - compiler/GHC/Linker/MacOS.hs - compiler/GHC/Runtime/Interpreter.hs - libraries/ghci/GHCi/Message.hs - libraries/ghci/GHCi/ObjLink.hs - libraries/ghci/GHCi/Run.hs - utils/jsffi/dyld.mjs Changes: ===================================== compiler/GHC/Driver/Plugins.hs ===================================== @@ -421,7 +421,7 @@ loadExternalPlugins ps = do loadExternalPluginLib :: FilePath -> IO () loadExternalPluginLib path = do -- load library - loadDLL path >>= \case + loadDLLs [path] >>= \case Left errmsg -> pprPanic "loadExternalPluginLib" (vcat [ text "Can't load plugin library" , text " Library path: " <> text path ===================================== compiler/GHC/Linker/Loader.hs ===================================== @@ -1,6 +1,7 @@ {-# LANGUAGE CPP #-} {-# LANGUAGE RecordWildCards #-} {-# LANGUAGE LambdaCase #-} +{-# LANGUAGE ViewPatterns #-} -- -- (c) The University of Glasgow 2002-2006 @@ -534,9 +535,10 @@ preloadLib interp hsc_env lib_paths framework_paths pls lib_spec = do return pls DLL dll_unadorned -> do - maybe_errstr <- loadDLL interp (platformSOName platform dll_unadorned) - case maybe_errstr of - Right _ -> maybePutStrLn logger "done" + res_e <- loadDLLs interp [platformSOName platform dll_unadorned] + case res_e of + Right [_] -> maybePutStrLn logger "done" + Right _ -> preloadFailed "unexpected LoadDLLs response" lib_paths lib_spec Left mm | platformOS platform /= OSDarwin -> preloadFailed mm lib_paths lib_spec Left mm | otherwise -> do @@ -544,17 +546,19 @@ preloadLib interp hsc_env lib_paths framework_paths pls lib_spec = do -- since (apparently) some things install that way - see -- ticket #8770. let libfile = ("lib" ++ dll_unadorned) <.> "so" - err2 <- loadDLL interp libfile - case err2 of - Right _ -> maybePutStrLn logger "done" - Left _ -> preloadFailed mm lib_paths lib_spec + err2_e <- loadDLLs interp [libfile] + case err2_e of + Right [_] -> maybePutStrLn logger "done" + Right _ -> preloadFailed mm lib_paths lib_spec + Left _ -> preloadFailed mm lib_paths lib_spec return pls DLLPath dll_path -> do - do maybe_errstr <- loadDLL interp dll_path - case maybe_errstr of - Right _ -> maybePutStrLn logger "done" - Left mm -> preloadFailed mm lib_paths lib_spec + do res_e <- loadDLLs interp [dll_path] + case res_e of + Right [_] -> maybePutStrLn logger "done" + Left mm -> preloadFailed mm lib_paths lib_spec + _ -> preloadFailed "unexpected LoadDLLs response" lib_paths lib_spec return pls Framework framework -> @@ -891,10 +895,11 @@ dynLoadObjs interp hsc_env pls@LoaderState{..} objs = do -- if we got this far, extend the lifetime of the library file changeTempFilesLifetime tmpfs TFL_GhcSession [soFile] - m <- loadDLL interp soFile - case m of - Right _ -> return $! pls { temp_sos = (libPath, libName) : temp_sos } - Left err -> linkFail msg (text err) + res <- loadDLLs interp [soFile] + case res of + Right [_] -> return $! pls { temp_sos = (libPath, libName) : temp_sos } + Left err -> linkFail msg (text err) + _ -> linkFail msg (text "unexpected LoadDLLs response") where msg = "GHC.Linker.Loader.dynLoadObjs: Loading temp shared object failed" @@ -1128,33 +1133,57 @@ loadPackages interp hsc_env new_pkgs = do loadPackages' :: Interp -> HscEnv -> [UnitId] -> LoaderState -> IO LoaderState loadPackages' interp hsc_env new_pks pls = do - pkgs' <- link (pkgs_loaded pls) new_pks - return $! pls { pkgs_loaded = pkgs' + (reverse -> pkgs_info_list, pkgs_almost_loaded) <- + downsweep + ([], pkgs_loaded pls) + new_pks + let link_one pkgs new_pkg_info = do + (hs_cls, extra_cls, loaded_dlls) <- + loadPackage + interp + hsc_env + new_pkg_info + evaluate $ + adjustUDFM + ( \old_pkg_info -> + old_pkg_info + { loaded_pkg_hs_objs = hs_cls, + loaded_pkg_non_hs_objs = extra_cls, + loaded_pkg_hs_dlls = loaded_dlls } + ) + pkgs + (Packages.unitId new_pkg_info) + pkgs_loaded' <- foldlM link_one pkgs_almost_loaded pkgs_info_list + evaluate $ pls {pkgs_loaded = pkgs_loaded'} where - link :: PkgsLoaded -> [UnitId] -> IO PkgsLoaded - link pkgs new_pkgs = - foldM link_one pkgs new_pkgs - - link_one pkgs new_pkg - | new_pkg `elemUDFM` pkgs -- Already linked - = return pkgs - - | Just pkg_cfg <- lookupUnitId (hsc_units hsc_env) new_pkg - = do { let deps = unitDepends pkg_cfg - -- Link dependents first - ; pkgs' <- link pkgs deps - -- Now link the package itself - ; (hs_cls, extra_cls, loaded_dlls) <- loadPackage interp hsc_env pkg_cfg - ; let trans_deps = unionManyUniqDSets [ addOneToUniqDSet (loaded_pkg_trans_deps loaded_pkg_info) dep_pkg - | dep_pkg <- deps - , Just loaded_pkg_info <- pure (lookupUDFM pkgs' dep_pkg) - ] - ; return (addToUDFM pkgs' new_pkg (LoadedPkgInfo new_pkg hs_cls extra_cls loaded_dlls trans_deps)) } - - | otherwise - = throwGhcExceptionIO (CmdLineError ("unknown package: " ++ unpackFS (unitIdFS new_pkg))) - + downsweep = foldlM downsweep_one + + downsweep_one (pkgs_info_list, pkgs) new_pkg + | new_pkg `elemUDFM` pkgs = pure (pkgs_info_list, pkgs) + | Just new_pkg_info <- lookupUnitId (hsc_units hsc_env) new_pkg = do + let new_pkg_deps = unitDepends new_pkg_info + (pkgs_info_list', pkgs') <- downsweep (pkgs_info_list, pkgs) new_pkg_deps + let new_pkg_trans_deps = + unionManyUniqDSets + [ addOneToUniqDSet (loaded_pkg_trans_deps loaded_pkg_info) dep_pkg + | dep_pkg <- new_pkg_deps, + loaded_pkg_info <- maybeToList $ pkgs' `lookupUDFM` dep_pkg + ] + pure + ( new_pkg_info : pkgs_info_list', + addToUDFM pkgs' new_pkg $ + LoadedPkgInfo + { loaded_pkg_uid = new_pkg, + loaded_pkg_hs_objs = [], + loaded_pkg_non_hs_objs = [], + loaded_pkg_hs_dlls = [], + loaded_pkg_trans_deps = new_pkg_trans_deps + } + ) + | otherwise = + throwGhcExceptionIO + (CmdLineError ("unknown package: " ++ unpackFS (unitIdFS new_pkg))) loadPackage :: Interp -> HscEnv -> UnitInfo -> IO ([LibrarySpec], [LibrarySpec], [RemotePtr LoadedDLL]) loadPackage interp hsc_env pkg @@ -1221,11 +1250,16 @@ loadPackage interp hsc_env pkg loadFrameworks interp platform pkg -- See Note [Crash early load_dyn and locateLib] -- Crash early if can't load any of `known_dlls` - mapM_ (load_dyn interp hsc_env True) known_extra_dlls - loaded_dlls <- mapMaybeM (load_dyn interp hsc_env True) known_hs_dlls + _ <- load_dyn interp hsc_env True known_extra_dlls + -- Batch-load Haskell package DLLs to allow downstream + -- interpreters/linkers to parallelize work (#25407). + res_loaded_dlls <- loadDLLs interp known_hs_dlls + loaded_dlls <- case res_loaded_dlls of + Right ds -> pure ds + Left e -> cmdLineErrorIO e -- For remaining `dlls` crash early only when there is surely -- no package's DLL around ... (not is_dyn) - mapM_ (load_dyn interp hsc_env (not is_dyn) . platformSOName platform) dlls + _ <- load_dyn interp hsc_env (not is_dyn) $ map (platformSOName platform) dlls #else let loaded_dlls = [] #endif @@ -1300,11 +1334,11 @@ restriction very easily. -- can be passed directly to loadDLL. They are either fully-qualified -- ("/usr/lib/libfoo.so"), or unqualified ("libfoo.so"). In the latter case, -- loadDLL is going to search the system paths to find the library. -load_dyn :: Interp -> HscEnv -> Bool -> FilePath -> IO (Maybe (RemotePtr LoadedDLL)) -load_dyn interp hsc_env crash_early dll = do - r <- loadDLL interp dll - case r of - Right loaded_dll -> pure (Just loaded_dll) +load_dyn :: Interp -> HscEnv -> Bool -> [FilePath] -> IO (Maybe [RemotePtr LoadedDLL]) +load_dyn interp hsc_env crash_early dlls = do + rs <- loadDLLs interp dlls + case rs of + Right loaded_dlls -> pure (Just loaded_dlls) Left err -> if crash_early then cmdLineErrorIO err ===================================== compiler/GHC/Linker/MacOS.hs ===================================== @@ -162,7 +162,7 @@ loadFramework interp extraPaths rootname -- sorry for the hardcoded paths, I hope they won't change anytime soon: defaultFrameworkPaths = ["/Library/Frameworks", "/System/Library/Frameworks"] - -- Try to call loadDLL for each candidate path. + -- Try to call loadDLLs for each candidate path. -- -- See Note [macOS Big Sur dynamic libraries] findLoadDLL [] errs = @@ -170,8 +170,9 @@ loadFramework interp extraPaths rootname -- has no built-in paths for frameworks: give up return $ Just errs findLoadDLL (p:ps) errs = - do { dll <- loadDLL interp (p fwk_file) - ; case dll of - Right _ -> return Nothing - Left err -> findLoadDLL ps ((p ++ ": " ++ err):errs) + do { res <- loadDLLs interp [p fwk_file] + ; case res of + Right [_] -> return Nothing + Left err -> findLoadDLL ps ((p ++ ": " ++ err):errs) + _ -> findLoadDLL ps ((p ++ ": unexpected LoadDLLs response"):errs) } ===================================== compiler/GHC/Runtime/Interpreter.hs ===================================== @@ -38,7 +38,7 @@ module GHC.Runtime.Interpreter , lookupSymbol , lookupSymbolInDLL , lookupClosure - , loadDLL + , loadDLLs , loadArchive , loadObj , unloadObj @@ -559,13 +559,10 @@ withSymbolCache interp str determine_addr = do purgeLookupSymbolCache :: Interp -> IO () purgeLookupSymbolCache interp = purgeInterpSymbolCache (interpSymbolCache interp) --- | loadDLL loads a dynamic library using the OS's native linker --- (i.e. dlopen() on Unix, LoadLibrary() on Windows). It takes either --- an absolute pathname to the file, or a relative filename --- (e.g. "libfoo.so" or "foo.dll"). In the latter case, loadDLL --- searches the standard locations for the appropriate library. -loadDLL :: Interp -> String -> IO (Either String (RemotePtr LoadedDLL)) -loadDLL interp str = interpCmd interp (LoadDLL str) +-- | Load multiple DLLs in one batch. Returns either an error (if any DLL fails) +-- or the list of successfully loaded DLL handles. +loadDLLs :: Interp -> [String] -> IO (Either String [RemotePtr LoadedDLL]) +loadDLLs interp strs = interpCmd interp (LoadDLLs strs) loadArchive :: Interp -> String -> IO () loadArchive interp path = do @@ -761,4 +758,3 @@ readIModModBreaks hug mod = imodBreaks_modBreaks . expectJust <$> readIModBreaks fromEvalResult :: EvalResult a -> IO a fromEvalResult (EvalException e) = throwIO (fromSerializableException e) fromEvalResult (EvalSuccess a) = return a - ===================================== libraries/ghci/GHCi/Message.hs ===================================== @@ -84,7 +84,8 @@ data Message a where LookupSymbol :: String -> Message (Maybe (RemotePtr ())) LookupSymbolInDLL :: RemotePtr LoadedDLL -> String -> Message (Maybe (RemotePtr ())) LookupClosure :: String -> Message (Maybe HValueRef) - LoadDLL :: String -> Message (Either String (RemotePtr LoadedDLL)) + -- | Load multiple DLLs in one batch + LoadDLLs :: [String] -> Message (Either String [RemotePtr LoadedDLL]) LoadArchive :: String -> Message () -- error? LoadObj :: String -> Message () -- error? UnloadObj :: String -> Message () -- error? @@ -441,7 +442,7 @@ data BreakModule -- that type isn't available here. data BreakUnitId --- | A dummy type that tags pointers returned by 'LoadDLL'. +-- | A dummy type that tags pointers returned by 'LoadDLLs'. data LoadedDLL -- SomeException can't be serialized because it contains dynamic @@ -555,7 +556,7 @@ getMessage = do 1 -> Msg <$> return InitLinker 2 -> Msg <$> LookupSymbol <$> get 3 -> Msg <$> LookupClosure <$> get - 4 -> Msg <$> LoadDLL <$> get + 4 -> Msg <$> LoadDLLs <$> get 5 -> Msg <$> LoadArchive <$> get 6 -> Msg <$> LoadObj <$> get 7 -> Msg <$> UnloadObj <$> get @@ -601,7 +602,7 @@ putMessage m = case m of InitLinker -> putWord8 1 LookupSymbol str -> putWord8 2 >> put str LookupClosure str -> putWord8 3 >> put str - LoadDLL str -> putWord8 4 >> put str + LoadDLLs strs -> putWord8 4 >> put strs LoadArchive str -> putWord8 5 >> put str LoadObj str -> putWord8 6 >> put str UnloadObj str -> putWord8 7 >> put str ===================================== libraries/ghci/GHCi/ObjLink.hs ===================================== @@ -12,7 +12,7 @@ -- dynamic linker. module GHCi.ObjLink ( initObjLinker, ShouldRetainCAFs(..) - , loadDLL + , loadDLLs , loadArchive , loadObj , unloadObj @@ -43,6 +43,10 @@ import Control.Exception (catch, evaluate) import GHC.Wasm.Prim #endif +#if defined(wasm32_HOST_ARCH) +import Data.List (intercalate) +#endif + -- --------------------------------------------------------------------------- -- RTS Linker Interface -- --------------------------------------------------------------------------- @@ -67,20 +71,25 @@ data ShouldRetainCAFs initObjLinker :: ShouldRetainCAFs -> IO () initObjLinker _ = pure () -loadDLL :: String -> IO (Either String (Ptr LoadedDLL)) -loadDLL f = +-- Batch load multiple DLLs at once via dyld to enable a single +-- dependency resolution and more parallel compilation. We pass a +-- NUL-delimited JSString to avoid array marshalling on wasm. +loadDLLs :: [String] -> IO (Either String [Ptr LoadedDLL]) +loadDLLs fs = m `catch` \(err :: JSException) -> - pure $ Left $ "loadDLL failed for " <> f <> ": " <> show err + pure $ Left $ "loadDLLs failed: " <> show err where + packed :: JSString + packed = toJSString (intercalate ['\0'] fs) m = do - evaluate =<< js_loadDLL (toJSString f) - pure $ Right nullPtr + evaluate =<< js_loadDLLs packed + pure $ Right (replicate (length fs) nullPtr) -- See Note [Variable passing in JSFFI] for where -- __ghc_wasm_jsffi_dyld comes from -foreign import javascript safe "__ghc_wasm_jsffi_dyld.loadDLL($1)" - js_loadDLL :: JSString -> IO () +foreign import javascript safe "__ghc_wasm_jsffi_dyld.loadDLLs($1)" + js_loadDLLs :: JSString -> IO () loadArchive :: String -> IO () loadArchive f = throwIO $ ErrorCall $ "loadArchive: unsupported on wasm for " <> f @@ -241,6 +250,17 @@ resolveObjs = do r <- c_resolveObjs return (r /= 0) +-- | Portable batch load: map 'loadDLL' and collect results. +loadDLLs :: [String] -> IO (Either String [Ptr LoadedDLL]) +loadDLLs = go [] + where + go acc [] = pure (Right (reverse acc)) + go acc (p:ps) = do + r <- loadDLL p + case r of + Left err -> pure (Left err) + Right h -> go (h:acc) ps + -- --------------------------------------------------------------------------- -- Foreign declarations to RTS entry points which does the real work; -- --------------------------------------------------------------------------- ===================================== libraries/ghci/GHCi/Run.hs ===================================== @@ -57,7 +57,7 @@ run m = case m of #if defined(javascript_HOST_ARCH) LoadObj p -> withCString p loadJS InitLinker -> notSupportedJS m - LoadDLL {} -> notSupportedJS m + LoadDLLs {} -> notSupportedJS m LoadArchive {} -> notSupportedJS m UnloadObj {} -> notSupportedJS m AddLibrarySearchPath {} -> notSupportedJS m @@ -69,7 +69,9 @@ run m = case m of LookupClosure str -> lookupJSClosure str #else InitLinker -> initObjLinker RetainCAFs - LoadDLL str -> fmap toRemotePtr <$> loadDLL str + LoadDLLs strs -> do + -- Always go through batch API. On non-wasm this falls back to per-DLL loads. + fmap (map toRemotePtr) <$> loadDLLs strs LoadArchive str -> loadArchive str LoadObj str -> loadObj str UnloadObj str -> unloadObj str ===================================== utils/jsffi/dyld.mjs ===================================== @@ -9,7 +9,7 @@ // iserv (GHCi.Server.defaultServer). This part only runs in // nodejs. // 2. Dynamic linker: provide RTS linker interfaces like -// loadDLL/lookupSymbol etc which are imported by wasm iserv. This +// loadDLLs/lookupSymbol etc which are imported by wasm iserv. This // part can run in browsers as well. // // When GHC starts external interpreter for the wasm target, it starts @@ -50,7 +50,7 @@ // // *** What works right now and what doesn't work yet? // -// loadDLL & bytecode interpreter work. Template Haskell & ghci work. +// loadDLLs & bytecode interpreter work. Template Haskell & ghci work. // Profiled dynamic code works. Compiled code and bytecode can all be // loaded, though the side effects are constrained to what's supported // by wasi preview1: we map the full host filesystem into wasm cause @@ -801,17 +801,17 @@ class DyLD { return this.#rpc.findSystemLibrary(f); } - // When we do loadDLL, we first perform "downsweep" which return a + // When we do loadDLLs, we first perform "downsweep" which return a // toposorted array of dependencies up to itself, then sequentially // load the downsweep result. // // The rationale of a separate downsweep phase, instead of a simple - // recursive loadDLL function is: V8 delegates async + // recursive loadDLLs function is: V8 delegates async // WebAssembly.compile to a background worker thread pool. To // maintain consistent internal linker state, we *must* load each so // file sequentially, but it's okay to kick off compilation asap, // store the Promise in downsweep result and await for the actual - // WebAssembly.Module in loadDLL logic. This way we can harness some + // WebAssembly.Module in loadDLLs logic. This way we can harness some // background parallelism. async #downsweep(p) { const toks = p.split("/"); @@ -852,8 +852,26 @@ class DyLD { return acc; } - // The real stuff - async loadDLL(p) { + // Batch load multiple DLLs in one go. + // Accepts a NUL-delimited string of paths to avoid array marshalling. + // Each path can be absolute or a soname; dependency resolution is + // performed across the full set to enable maximal parallel compile + // while maintaining sequential instantiation order. + async loadDLLs(packed) { + // Normalize input to an array of strings. When called from Haskell + // we pass a single JSString containing NUL-separated paths. + const paths = (typeof packed === "string" + ? (packed.length === 0 ? [] : packed.split("\0")) + : [packed] // tolerate an accidental single path object + ).filter((s) => s.length > 0); + + // Compute a single downsweep plan for the whole batch. + // Note: #downsweep mutates #loadedSos to break cycles and dedup. + const plan = []; + for (const p of paths) { + plan.push(...(await this.#downsweep(p))); + } + for (const { memSize, memP2Align, @@ -861,7 +879,7 @@ class DyLD { tableP2Align, modp, soname, - } of await this.#downsweep(p)) { + } of plan) { const import_obj = { wasi_snapshot_preview1: this.#wasi.wasiImport, env: { @@ -1138,7 +1156,7 @@ export async function main({ rpc, libdir, ghciSoPath, args }) { rpc, }); await dyld.addLibrarySearchPath(libdir); - await dyld.loadDLL(ghciSoPath); + await dyld.loadDLLs(ghciSoPath); const reader = rpc.readStream.getReader(); const writer = rpc.writeStream.getWriter(); View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/98c839ddd9ea9beeef0fe2dda49ac45... -- View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/98c839ddd9ea9beeef0fe2dda49ac45... 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