X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2FsimplCore%2FSimplCore.lhs;h=5636fedbb4859f562d60c796ff73d63caf58ab37;hb=19fcb519897270c9fcd2c0f707636e9682ff1b08;hp=fc5b90323076546085075bf49c2f6ab8b08dc52d;hpb=b4229ab662b6d87b1477bafa85d2db46e5a9a152;p=ghc-hetmet.git diff --git a/compiler/simplCore/SimplCore.lhs b/compiler/simplCore/SimplCore.lhs index fc5b903..5636fed 100644 --- a/compiler/simplCore/SimplCore.lhs +++ b/compiler/simplCore/SimplCore.lhs @@ -22,20 +22,22 @@ import CoreSyn import HscTypes import CSE ( cseProgram ) import Rules ( RuleBase, emptyRuleBase, mkRuleBase, unionRuleBase, - extendRuleBaseList, pprRuleBase, ruleCheckProgram, + extendRuleBaseList, pprRuleBase, pprRulesForUser, + ruleCheckProgram, rulesOfBinds, addSpecInfo, addIdSpecialisations ) import PprCore ( pprCoreBindings, pprCoreExpr, pprRules ) import OccurAnal ( occurAnalysePgm, occurAnalyseExpr ) import IdInfo ( setNewStrictnessInfo, newStrictnessInfo, - setWorkerInfo, workerInfo, setSpecInfoHead, + setUnfoldingInfo, unfoldingInfo, setSpecInfoHead, setInlinePragInfo, inlinePragInfo, setSpecInfo, specInfo, specInfoRules ) import CoreUtils ( coreBindsSize ) import Simplify ( simplTopBinds, simplExpr ) import SimplEnv ( SimplEnv, simplBinders, mkSimplEnv, setInScopeSet ) import SimplMonad -import ErrUtils ( dumpIfSet, dumpIfSet_dyn, showPass ) -import CoreLint ( endPassIf, endIteration ) +import CoreMonad +import qualified ErrUtils as Err ( dumpIfSet_dyn, dumpIfSet, showPass ) +import CoreLint ( showPass, endPass, endPassIf, endIteration ) import FloatIn ( floatInwards ) import FloatOut ( floatOutwards ) import FamInstEnv @@ -43,6 +45,7 @@ import Id import DataCon import TyCon ( tyConSelIds, tyConDataCons ) import Class ( classSelIds ) +import BasicTypes ( CompilerPhase, isActive ) import VarSet import VarEnv import NameEnv ( lookupNameEnv ) @@ -57,11 +60,14 @@ import StrictAnal ( saBinds ) import CprAnalyse ( cprAnalyse ) #endif import Vectorise ( vectorise ) +import FastString +import Util import UniqSupply ( UniqSupply, mkSplitUniqSupply, splitUniqSupply ) import IO ( hPutStr, stderr ) import Outputable -import List ( partition ) +import Control.Monad +import List ( partition, intersperse ) import Maybes \end{code} @@ -76,33 +82,40 @@ core2core :: HscEnv -> ModGuts -> IO ModGuts -core2core hsc_env guts - = do { - ; let dflags = hsc_dflags hsc_env - core_todos = getCoreToDo dflags +core2core hsc_env guts = do + let dflags = hsc_dflags hsc_env + + us <- mkSplitUniqSupply 's' + let (cp_us, ru_us) = splitUniqSupply us - ; us <- mkSplitUniqSupply 's' - ; let (cp_us, ru_us) = splitUniqSupply us + -- COMPUTE THE ANNOTATIONS TO USE + ann_env <- prepareAnnotations hsc_env (Just guts) - -- COMPUTE THE RULE BASE TO USE - ; (imp_rule_base, guts1) <- prepareRules hsc_env guts ru_us + -- COMPUTE THE RULE BASE TO USE + (imp_rule_base, guts1) <- prepareRules hsc_env guts ru_us - -- Note [Injecting implicit bindings] - ; let implicit_binds = getImplicitBinds (mg_types guts1) - guts2 = guts1 { mg_binds = implicit_binds ++ mg_binds guts1 } + -- Get the module out of the current HscEnv so we can retrieve it from the monad. + -- This is very convienent for the users of the monad (e.g. plugins do not have to + -- consume the ModGuts to find the module) but somewhat ugly because mg_module may + -- _theoretically_ be changed during the Core pipeline (it's part of ModGuts), which + -- would mean our cached value would go out of date. + let mod = mg_module guts + (guts2, stats) <- runCoreM hsc_env ann_env imp_rule_base cp_us mod $ do + -- FIND BUILT-IN PASSES + let builtin_core_todos = getCoreToDo dflags - -- DO THE BUSINESS - ; (stats, guts3) <- doCorePasses hsc_env imp_rule_base cp_us - (zeroSimplCount dflags) - guts2 core_todos + -- DO THE BUSINESS + doCorePasses builtin_core_todos guts1 - ; dumpIfSet_dyn dflags Opt_D_dump_simpl_stats - "Grand total simplifier statistics" - (pprSimplCount stats) + Err.dumpIfSet_dyn dflags Opt_D_dump_simpl_stats + "Grand total simplifier statistics" + (pprSimplCount stats) - ; return guts3 } + return guts2 +type CorePass = CoreToDo + simplifyExpr :: DynFlags -- includes spec of what core-to-core passes to do -> CoreExpr -> IO CoreExpr @@ -110,14 +123,14 @@ simplifyExpr :: DynFlags -- includes spec of what core-to-core passes to do -- expression typed in at the interactive prompt simplifyExpr dflags expr = do { - ; showPass dflags "Simplify" + ; Err.showPass dflags "Simplify" ; us <- mkSplitUniqSupply 's' ; let (expr', _counts) = initSmpl dflags emptyRuleBase emptyFamInstEnvs us $ simplExprGently gentleSimplEnv expr - ; dumpIfSet_dyn dflags Opt_D_dump_simpl "Simplified expression" + ; Err.dumpIfSet_dyn dflags Opt_D_dump_simpl "Simplified expression" (pprCoreExpr expr') ; return expr' @@ -126,135 +139,165 @@ simplifyExpr dflags expr gentleSimplEnv :: SimplEnv gentleSimplEnv = mkSimplEnv SimplGently (isAmongSimpl []) -doCorePasses :: HscEnv - -> RuleBase -- the imported main rule base - -> UniqSupply -- uniques - -> SimplCount -- simplifier stats - -> ModGuts -- local binds in (with rules attached) - -> [CoreToDo] -- which passes to do - -> IO (SimplCount, ModGuts) - -doCorePasses hsc_env rb us stats guts [] - = return (stats, guts) - -doCorePasses hsc_env rb us stats guts (CoreDoPasses to_dos1 : to_dos2) - = doCorePasses hsc_env rb us stats guts (to_dos1 ++ to_dos2) - -doCorePasses hsc_env rb us stats guts (to_do : to_dos) - = do - let (us1, us2) = splitUniqSupply us - (stats1, guts1) <- doCorePass to_do hsc_env us1 rb guts - doCorePasses hsc_env rb us2 (stats `plusSimplCount` stats1) guts1 to_dos - -doCorePass :: CoreToDo -> HscEnv -> UniqSupply -> RuleBase - -> ModGuts -> IO (SimplCount, ModGuts) -doCorePass (CoreDoSimplify mode sws) = {-# SCC "Simplify" #-} simplifyPgm mode sws -doCorePass CoreCSE = {-# SCC "CommonSubExpr" #-} trBinds cseProgram -doCorePass CoreLiberateCase = {-# SCC "LiberateCase" #-} liberateCase -doCorePass CoreDoFloatInwards = {-# SCC "FloatInwards" #-} trBinds floatInwards -doCorePass (CoreDoFloatOutwards f) = {-# SCC "FloatOutwards" #-} trBindsU (floatOutwards f) -doCorePass CoreDoStaticArgs = {-# SCC "StaticArgs" #-} trBinds doStaticArgs -doCorePass CoreDoStrictness = {-# SCC "Stranal" #-} trBinds dmdAnalPgm -doCorePass CoreDoWorkerWrapper = {-# SCC "WorkWrap" #-} trBindsU wwTopBinds -doCorePass CoreDoSpecialising = {-# SCC "Specialise" #-} trBindsU specProgram -doCorePass CoreDoSpecConstr = {-# SCC "SpecConstr" #-} trBindsU specConstrProgram -doCorePass CoreDoGlomBinds = trBinds glomBinds -doCorePass CoreDoVectorisation = {-# SCC "Vectorise" #-} vectorise -doCorePass CoreDoPrintCore = observe printCore -doCorePass (CoreDoRuleCheck phase pat) = ruleCheck phase pat -doCorePass CoreDoNothing = observe (\ _ _ -> return ()) -#ifdef OLD_STRICTNESS -doCorePass CoreDoOldStrictness = {-# SCC "OldStrictness" #-} trBinds doOldStrictness -#else -doCorePass CoreDoOldStrictness = panic "CoreDoOldStrictness" -#endif -doCorePass (CoreDoPasses _) = panic "CoreDoPasses" +doCorePasses :: [CorePass] -> ModGuts -> CoreM ModGuts +doCorePasses passes guts = foldM (flip doCorePass) guts passes + +doCorePass :: CorePass -> ModGuts -> CoreM ModGuts +doCorePass (CoreDoSimplify mode sws) = {-# SCC "Simplify" #-} + simplifyPgm mode sws + +doCorePass CoreCSE = {-# SCC "CommonSubExpr" #-} + describePass "Common sub-expression" Opt_D_dump_cse $ + doPass cseProgram + +doCorePass CoreLiberateCase = {-# SCC "LiberateCase" #-} + describePass "Liberate case" Opt_D_verbose_core2core $ + doPassD liberateCase + +doCorePass CoreDoFloatInwards = {-# SCC "FloatInwards" #-} + describePass "Float inwards" Opt_D_verbose_core2core $ + doPass floatInwards + +doCorePass (CoreDoFloatOutwards f) = {-# SCC "FloatOutwards" #-} + describePassD (text "Float out" <+> parens (ppr f)) + Opt_D_verbose_core2core $ + doPassDUM (floatOutwards f) + +doCorePass CoreDoStaticArgs = {-# SCC "StaticArgs" #-} + describePass "Static argument" Opt_D_verbose_core2core $ + doPassU doStaticArgs + +doCorePass CoreDoStrictness = {-# SCC "Stranal" #-} + describePass "Demand analysis" Opt_D_dump_stranal $ + doPassDM dmdAnalPgm + +doCorePass CoreDoWorkerWrapper = {-# SCC "WorkWrap" #-} + describePass "Worker Wrapper binds" Opt_D_dump_worker_wrapper $ + doPassU wwTopBinds + +doCorePass CoreDoSpecialising = {-# SCC "Specialise" #-} + describePassR "Specialise" Opt_D_dump_spec $ + doPassU specProgram + +doCorePass CoreDoSpecConstr = {-# SCC "SpecConstr" #-} + describePassR "SpecConstr" Opt_D_dump_spec $ + doPassDU specConstrProgram + +doCorePass (CoreDoVectorisation be) = {-# SCC "Vectorise" #-} + describePass "Vectorisation" Opt_D_dump_vect $ + vectorise be + +doCorePass CoreDoGlomBinds = dontDescribePass $ doPassDM glomBinds +doCorePass CoreDoPrintCore = dontDescribePass $ observe printCore +doCorePass (CoreDoRuleCheck phase pat) = dontDescribePass $ ruleCheck phase pat #ifdef OLD_STRICTNESS -doOldStrictness dfs binds - = do binds1 <- saBinds dfs binds - binds2 <- cprAnalyse dfs binds1 - return binds2 +doCorePass CoreDoOldStrictness = {-# SCC "OldStrictness" #-} doOldStrictness #endif -printCore _ binds = dumpIfSet True "Print Core" (pprCoreBindings binds) - -ruleCheck phase pat hsc_env us rb guts - = do let dflags = hsc_dflags hsc_env - showPass dflags "RuleCheck" - printDump (ruleCheckProgram phase pat rb (mg_binds guts)) - return (zeroSimplCount dflags, guts) - --- Most passes return no stats and don't change rules -trBinds :: (DynFlags -> [CoreBind] -> IO [CoreBind]) - -> HscEnv -> UniqSupply -> RuleBase -> ModGuts - -> IO (SimplCount, ModGuts) -trBinds do_pass hsc_env us rb guts - = do { binds' <- do_pass dflags (mg_binds guts) - ; return (zeroSimplCount dflags, guts { mg_binds = binds' }) } - where - dflags = hsc_dflags hsc_env - -trBindsU :: (DynFlags -> UniqSupply -> [CoreBind] -> IO [CoreBind]) - -> HscEnv -> UniqSupply -> RuleBase -> ModGuts - -> IO (SimplCount, ModGuts) -trBindsU do_pass hsc_env us rb guts - = do { binds' <- do_pass dflags us (mg_binds guts) - ; return (zeroSimplCount dflags, guts { mg_binds = binds' }) } - where - dflags = hsc_dflags hsc_env +doCorePass CoreDoNothing = return +doCorePass (CoreDoPasses passes) = doCorePasses passes --- Observer passes just peek; don't modify the bindings at all -observe :: (DynFlags -> [CoreBind] -> IO a) - -> HscEnv -> UniqSupply -> RuleBase -> ModGuts - -> IO (SimplCount, ModGuts) -observe do_pass hsc_env us rb guts - = do { binds <- do_pass dflags (mg_binds guts) - ; return (zeroSimplCount dflags, guts) } - where - dflags = hsc_dflags hsc_env -\end{code} +#ifdef OLD_STRICTNESS +doOldStrictness :: ModGuts -> CoreM ModGuts +doOldStrictness guts + = do dfs <- getDynFlags + guts' <- describePass "Strictness analysis" Opt_D_dump_stranal $ + doPassM (saBinds dfs) guts + guts'' <- describePass "Constructed Product analysis" Opt_D_dump_cpranal $ + doPass cprAnalyse guts' + return guts'' +#endif +\end{code} %************************************************************************ %* * - Implicit bindings +\subsection{Core pass combinators} %* * %************************************************************************ -Note [Injecting implicit bindings] -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -We used to inject the implict bindings right at the end, in CoreTidy. -But some of these bindings, notably record selectors, are not -constructed in an optimised form. E.g. record selector for - data T = MkT { x :: {-# UNPACK #-} !Int } -Then the unfolding looks like - x = \t. case t of MkT x1 -> let x = I# x1 in x -This generates bad code unless it's first simplified a bit. -(Only matters when the selector is used curried; eg map x ys.) -See Trac #2070. - \begin{code} -getImplicitBinds :: TypeEnv -> [CoreBind] -getImplicitBinds type_env - = map get_defn (concatMap implicit_con_ids (typeEnvTyCons type_env) - ++ concatMap other_implicit_ids (typeEnvElts type_env)) - -- Put the constructor wrappers first, because - -- other implicit bindings (notably the fromT functions arising - -- from generics) use the constructor wrappers. At least that's - -- what External Core likes - where - implicit_con_ids tc = mapCatMaybes dataConWrapId_maybe (tyConDataCons tc) + +dontDescribePass :: (ModGuts -> CoreM ModGuts) -> ModGuts -> CoreM ModGuts +dontDescribePass = ($) + +describePass :: String -> DynFlag -> (ModGuts -> CoreM ModGuts) -> ModGuts -> CoreM ModGuts +describePass name dflag pass guts = do + dflags <- getDynFlags - other_implicit_ids (ATyCon tc) = filter (not . isNaughtyRecordSelector) (tyConSelIds tc) - -- The "naughty" ones are not real functions at all - -- They are there just so we can get decent error messages - -- See Note [Naughty record selectors] in MkId.lhs - other_implicit_ids (AClass cl) = classSelIds cl - other_implicit_ids _other = [] + liftIO $ showPass dflags name + guts' <- pass guts + liftIO $ endPass dflags name dflag (mg_binds guts') - get_defn :: Id -> CoreBind - get_defn id = NonRec id (unfoldingTemplate (idUnfolding id)) + return guts' + +describePassD :: SDoc -> DynFlag -> (ModGuts -> CoreM ModGuts) -> ModGuts -> CoreM ModGuts +describePassD doc = describePass (showSDoc doc) + +describePassR :: String -> DynFlag -> (ModGuts -> CoreM ModGuts) -> ModGuts -> CoreM ModGuts +describePassR name dflag pass guts = do + guts' <- describePass name dflag pass guts + dumpIfSet_dyn Opt_D_dump_rules "Top-level specialisations" + (pprRulesForUser (rulesOfBinds (mg_binds guts'))) + return guts' + +printCore _ binds = Err.dumpIfSet True "Print Core" (pprCoreBindings binds) + +ruleCheck :: CompilerPhase -> String -> ModGuts -> CoreM ModGuts +ruleCheck current_phase pat guts = do + let is_active = isActive current_phase + rb <- getRuleBase + dflags <- getDynFlags + liftIO $ Err.showPass dflags "RuleCheck" + liftIO $ printDump (ruleCheckProgram is_active pat rb (mg_binds guts)) + return guts + + +doPassDMS :: (DynFlags -> [CoreBind] -> IO (SimplCount, [CoreBind])) -> ModGuts -> CoreM ModGuts +doPassDMS do_pass = doPassM $ \binds -> do + dflags <- getDynFlags + liftIOWithCount $ do_pass dflags binds + +doPassDUM :: (DynFlags -> UniqSupply -> [CoreBind] -> IO [CoreBind]) -> ModGuts -> CoreM ModGuts +doPassDUM do_pass = doPassM $ \binds -> do + dflags <- getDynFlags + us <- getUniqueSupplyM + liftIO $ do_pass dflags us binds + +doPassDM :: (DynFlags -> [CoreBind] -> IO [CoreBind]) -> ModGuts -> CoreM ModGuts +doPassDM do_pass = doPassDUM (\dflags -> const (do_pass dflags)) + +doPassD :: (DynFlags -> [CoreBind] -> [CoreBind]) -> ModGuts -> CoreM ModGuts +doPassD do_pass = doPassDM (\dflags -> return . do_pass dflags) + +doPassDU :: (DynFlags -> UniqSupply -> [CoreBind] -> [CoreBind]) -> ModGuts -> CoreM ModGuts +doPassDU do_pass = doPassDUM (\dflags us -> return . do_pass dflags us) + +doPassU :: (UniqSupply -> [CoreBind] -> [CoreBind]) -> ModGuts -> CoreM ModGuts +doPassU do_pass = doPassDU (const do_pass) + +-- Most passes return no stats and don't change rules: these combinators +-- let us lift them to the full blown ModGuts+CoreM world +doPassM :: Monad m => ([CoreBind] -> m [CoreBind]) -> ModGuts -> m ModGuts +doPassM bind_f guts = do + binds' <- bind_f (mg_binds guts) + return (guts { mg_binds = binds' }) + +doPassMG :: Monad m => (ModGuts -> m [CoreBind]) -> ModGuts -> m ModGuts +doPassMG bind_f guts = do + binds' <- bind_f guts + return (guts { mg_binds = binds' }) + +doPass :: ([CoreBind] -> [CoreBind]) -> ModGuts -> CoreM ModGuts +doPass bind_f guts = return $ guts { mg_binds = bind_f (mg_binds guts) } + +-- Observer passes just peek; don't modify the bindings at all +observe :: (DynFlags -> [CoreBind] -> IO a) -> ModGuts -> CoreM ModGuts +observe do_pass = doPassM $ \binds -> do + dflags <- getDynFlags + liftIO $ do_pass dflags binds + return binds \end{code} @@ -279,43 +322,34 @@ prepareRules :: HscEnv ModGuts) -- Modified fields are -- (a) Bindings have rules attached, + -- and INLINE rules simplified -- (b) Rules are now just orphan rules prepareRules hsc_env@(HscEnv { hsc_dflags = dflags, hsc_HPT = hpt }) - guts@(ModGuts { mg_binds = binds, mg_deps = deps, mg_rules = local_rules }) + guts@(ModGuts { mg_binds = binds, mg_deps = deps + , mg_rules = local_rules, mg_rdr_env = rdr_env }) us - = do { let -- Simplify the local rules; boringly, we need to make an in-scope set + = do { us <- mkSplitUniqSupply 'w' + + ; let -- Simplify the local rules; boringly, we need to make an in-scope set -- from the local binders, to avoid warnings from Simplify.simplVar local_ids = mkInScopeSet (mkVarSet (bindersOfBinds binds)) env = setInScopeSet gentleSimplEnv local_ids - (better_rules,_) = initSmpl dflags emptyRuleBase emptyFamInstEnvs us $ - (mapM (simplRule env) local_rules) - home_pkg_rules = hptRules hsc_env (dep_mods deps) - - -- Find the rules for locally-defined Ids; then we can attach them - -- to the binders in the top-level bindings - -- - -- Reason - -- - It makes the rules easier to look up - -- - It means that transformation rules and specialisations for - -- locally defined Ids are handled uniformly - -- - It keeps alive things that are referred to only from a rule - -- (the occurrence analyser knows about rules attached to Ids) - -- - It makes sure that, when we apply a rule, the free vars - -- of the RHS are more likely to be in scope - -- - The imported rules are carried in the in-scope set - -- which is extended on each iteration by the new wave of - -- local binders; any rules which aren't on the binding will - -- thereby get dropped - (rules_for_locals, rules_for_imps) = partition isLocalRule better_rules - local_rule_base = extendRuleBaseList emptyRuleBase rules_for_locals - binds_w_rules = updateBinders local_rule_base binds - - hpt_rule_base = mkRuleBase home_pkg_rules - imp_rule_base = extendRuleBaseList hpt_rule_base rules_for_imps - - ; dumpIfSet_dyn dflags Opt_D_dump_rules "Transformation rules" - (vcat [text "Local rules", pprRules better_rules, + (simpl_rules, _) = initSmpl dflags emptyRuleBase emptyFamInstEnvs us $ + mapM (simplRule env) local_rules + + ; let (rules_for_locals, rules_for_imps) = partition isLocalRule simpl_rules + + home_pkg_rules = hptRules hsc_env (dep_mods deps) + hpt_rule_base = mkRuleBase home_pkg_rules + imp_rule_base = extendRuleBaseList hpt_rule_base rules_for_imps + + binds_w_rules = updateBinders rules_for_locals binds + + + ; Err.dumpIfSet_dyn dflags Opt_D_dump_rules "Transformation rules" + (withPprStyle (mkUserStyle (mkPrintUnqualified dflags rdr_env) AllTheWay) $ + vcat [text "Local rules", pprRules simpl_rules, text "", text "Imported rules", pprRuleBase imp_rule_base]) @@ -323,26 +357,59 @@ prepareRules hsc_env@(HscEnv { hsc_dflags = dflags, hsc_HPT = hpt }) mg_rules = rules_for_imps }) } -updateBinders :: RuleBase -> [CoreBind] -> [CoreBind] -updateBinders local_rules binds - = map update_bndrs binds +-- Note [Attach rules to local ids] +-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +-- Find the rules for locally-defined Ids; then we can attach them +-- to the binders in the top-level bindings +-- +-- Reason +-- - It makes the rules easier to look up +-- - It means that transformation rules and specialisations for +-- locally defined Ids are handled uniformly +-- - It keeps alive things that are referred to only from a rule +-- (the occurrence analyser knows about rules attached to Ids) +-- - It makes sure that, when we apply a rule, the free vars +-- of the RHS are more likely to be in scope +-- - The imported rules are carried in the in-scope set +-- which is extended on each iteration by the new wave of +-- local binders; any rules which aren't on the binding will +-- thereby get dropped + +updateBinders :: [CoreRule] -> [CoreBind] -> [CoreBind] +updateBinders rules_for_locals binds + = map update_bind binds where - update_bndrs (NonRec b r) = NonRec (update_bndr b) r - update_bndrs (Rec prs) = Rec [(update_bndr b, r) | (b,r) <- prs] - - update_bndr bndr = case lookupNameEnv local_rules (idName bndr) of - Nothing -> bndr - Just rules -> bndr `addIdSpecialisations` rules - -- The binder might have some existing rules, - -- arising from specialisation pragmas + local_rules = extendRuleBaseList emptyRuleBase rules_for_locals + + update_bind (NonRec b r) = NonRec (add_rules b) r + update_bind (Rec prs) = Rec (mapFst add_rules prs) + + -- See Note [Attach rules to local ids] + -- NB: the binder might have some existing rules, + -- arising from specialisation pragmas + add_rules bndr + | Just rules <- lookupNameEnv local_rules (idName bndr) + = bndr `addIdSpecialisations` rules + | otherwise + = bndr \end{code} - -We must do some gentle simplification on the template (but not the RHS) -of each rule. The case that forced me to add this was the fold/build rule, +Note [Simplifying the left-hand side of a RULE] +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +We must do some gentle simplification on the lhs (template) of each +rule. The case that forced me to add this was the fold/build rule, which without simplification looked like: fold k z (build (/\a. g a)) ==> ... This doesn't match unless you do eta reduction on the build argument. +Similarly for a LHS like + augment g (build h) +we do not want to get + augment (\a. g a) (build h) +otherwise we don't match when given an argument like + augment (\a. h a a) (build h) + +The simplifier does indeed do eta reduction (it's in +Simplify.completeLam) but only if -O is on. \begin{code} simplRule env rule@(BuiltinRule {}) @@ -352,17 +419,6 @@ simplRule env rule@(Rule { ru_bndrs = bndrs, ru_args = args, ru_rhs = rhs }) args' <- mapM (simplExprGently env) args rhs' <- simplExprGently env rhs return (rule { ru_bndrs = bndrs', ru_args = args', ru_rhs = rhs' }) - --- It's important that simplExprGently does eta reduction. --- For example, in a rule like: --- augment g (build h) --- we do not want to get --- augment (\a. g a) (build h) --- otherwise we don't match when given an argument like --- (\a. h a a) --- --- The simplifier does indeed do eta reduction (it's in --- Simplify.completeLam) but only if -O is on. \end{code} \begin{code} @@ -373,11 +429,17 @@ simplExprGently :: SimplEnv -> CoreExpr -> SimplM CoreExpr -- alone leaves tons of crud. -- Used (a) for user expressions typed in at the interactive prompt -- (b) the LHS and RHS of a RULE +-- (c) Template Haskell splices -- -- The name 'Gently' suggests that the SimplifierMode is SimplGently, -- and in fact that is so.... but the 'Gently' in simplExprGently doesn't -- enforce that; it just simplifies the expression twice +-- It's important that simplExprGently does eta reduction; see +-- Note [Simplifying the left-hand side of a RULE] above. The +-- simplifier does indeed do eta reduction (it's in Simplify.completeLam) +-- but only if -O is on. + simplExprGently env expr = do expr1 <- simplExpr env (occurAnalyseExpr expr) simplExpr env (occurAnalyseExpr expr1) @@ -418,7 +480,7 @@ glomBinds :: DynFlags -> [CoreBind] -> IO [CoreBind] -- analyser as free in f. glomBinds dflags binds - = do { showPass dflags "GlomBinds" ; + = do { Err.showPass dflags "GlomBinds" ; let { recd_binds = [Rec (flattenBinds binds)] } ; return recd_binds } -- Not much point in printing the result... @@ -433,40 +495,46 @@ glomBinds dflags binds %************************************************************************ \begin{code} -simplifyPgm :: SimplifierMode +simplifyPgm :: SimplifierMode -> [SimplifierSwitch] -> ModGuts -> CoreM ModGuts +simplifyPgm mode switches + = describePassD doc Opt_D_dump_simpl_phases $ \guts -> + do { hsc_env <- getHscEnv + ; us <- getUniqueSupplyM + ; rb <- getRuleBase + ; let fam_inst_env = mg_fam_inst_env guts + dump_phase = shouldDumpSimplPhase (hsc_dflags hsc_env) mode + simplify_pgm = simplifyPgmIO dump_phase mode switches + hsc_env us rb fam_inst_env + + ; doPassM (liftIOWithCount . simplify_pgm) guts } + where + doc = ptext (sLit "Simplifier Phase") <+> text (showPpr mode) + +simplifyPgmIO :: Bool + -> SimplifierMode -> [SimplifierSwitch] -> HscEnv -> UniqSupply -> RuleBase - -> ModGuts - -> IO (SimplCount, ModGuts) -- New bindings + -> FamInstEnv + -> [CoreBind] + -> IO (SimplCount, [CoreBind]) -- New bindings -simplifyPgm mode switches hsc_env us imp_rule_base guts +simplifyPgmIO dump_phase mode switches hsc_env us imp_rule_base fam_inst_env binds = do { - showPass dflags "Simplify"; - (termination_msg, it_count, counts_out, binds') - <- do_iteration us 1 (zeroSimplCount dflags) (mg_binds guts) ; + <- do_iteration us 1 (zeroSimplCount dflags) binds ; - dumpIfSet (dump_phase && dopt Opt_D_dump_simpl_stats dflags) - "Simplifier statistics" + Err.dumpIfSet (dump_phase && dopt Opt_D_dump_simpl_stats dflags) + "Simplifier statistics for following pass" (vcat [text termination_msg <+> text "after" <+> ppr it_count <+> text "iterations", text "", pprSimplCount counts_out]); - endPassIf dump_phase dflags - ("Simplify phase " ++ phase_info ++ " done") - Opt_D_dump_simpl_phases binds'; - - return (counts_out, guts { mg_binds = binds' }) + return (counts_out, binds') } where dflags = hsc_dflags hsc_env - phase_info = case mode of - SimplGently -> "gentle" - SimplPhase n -> show n - - dump_phase = shouldDumpSimplPhase dflags mode sw_chkr = isAmongSimpl switches max_iterations = intSwitchSet sw_chkr MaxSimplifierIterations `orElse` 2 @@ -475,19 +543,13 @@ simplifyPgm mode switches hsc_env us imp_rule_base guts -- iteration_no is the number of the iteration we are -- about to begin, with '1' for the first | iteration_no > max_iterations -- Stop if we've run out of iterations - = do { -#ifdef DEBUG - if max_iterations > 2 then - hPutStr stderr ("NOTE: Simplifier still going after " ++ - show max_iterations ++ - " iterations; bailing out. Size = " ++ show (coreBindsSize binds) ++ "\n" ) - else - return (); -#endif + = WARN(debugIsOn && (max_iterations > 2), + text ("Simplifier still going after " ++ + show max_iterations ++ + " iterations; bailing out. Size = " ++ show (coreBindsSize binds) ++ "\n" )) -- Subtract 1 from iteration_no to get the -- number of iterations we actually completed - return ("Simplifier baled out", iteration_no - 1, counts, binds) - } + return ("Simplifier bailed out", iteration_no - 1, counts, binds) -- Try and force thunks off the binds; significantly reduces -- space usage, especially with -O. JRS, 000620. @@ -495,7 +557,7 @@ simplifyPgm mode switches hsc_env us imp_rule_base guts = do { -- Occurrence analysis let { tagged_binds = {-# SCC "OccAnal" #-} occurAnalysePgm binds } ; - dumpIfSet_dyn dflags Opt_D_dump_occur_anal "Occurrence analysis" + Err.dumpIfSet_dyn dflags Opt_D_dump_occur_anal "Occurrence analysis" (pprCoreBindings tagged_binds); -- Get any new rules, and extend the rule base @@ -508,7 +570,7 @@ simplifyPgm mode switches hsc_env us imp_rule_base guts ; simpl_env = mkSimplEnv mode sw_chkr ; simpl_binds = {-# SCC "SimplTopBinds" #-} simplTopBinds simpl_env tagged_binds - ; fam_envs = (eps_fam_inst_env eps, mg_fam_inst_env guts) } ; + ; fam_envs = (eps_fam_inst_env eps, fam_inst_env) } ; -- Simplify the program -- We do this with a *case* not a *let* because lazy pattern @@ -525,7 +587,7 @@ simplifyPgm mode switches hsc_env us imp_rule_base guts (binds', counts') -> do { let { all_counts = counts `plusSimplCount` counts' - ; herald = "Simplifier phase " ++ phase_info ++ + ; herald = "Simplifier mode " ++ showPpr mode ++ ", iteration " ++ show iteration_no ++ " out of " ++ show max_iterations } ; @@ -546,7 +608,7 @@ simplifyPgm mode switches hsc_env us imp_rule_base guts let { binds'' = {-# SCC "ZapInd" #-} shortOutIndirections binds' } ; -- Dump the result of this iteration - dumpIfSet_dyn dflags Opt_D_dump_simpl_iterations herald + Err.dumpIfSet_dyn dflags Opt_D_dump_simpl_iterations herald (pprSimplCount counts') ; endIteration dflags herald Opt_D_dump_simpl_iterations binds'' ; @@ -749,7 +811,7 @@ transferIdInfo exported_id local_id where local_info = idInfo local_id transfer exp_info = exp_info `setNewStrictnessInfo` newStrictnessInfo local_info - `setWorkerInfo` workerInfo local_info + `setUnfoldingInfo` unfoldingInfo local_info `setInlinePragInfo` inlinePragInfo local_info `setSpecInfo` addSpecInfo (specInfo exp_info) new_info new_info = setSpecInfoHead (idName exported_id)