X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2FsimplCore%2FSimplCore.lhs;h=8843455afd50d2e2319e78cf30beee1c2867c366;hb=d876992cf9b9fb07cb913b0c297d9a42b746c29a;hp=bcfbbfa4931904a4ba20e63dd857e6c9945ea268;hpb=82f63df94dafed10f51f158ab531d52da97c2c86;p=ghc-hetmet.git diff --git a/ghc/compiler/simplCore/SimplCore.lhs b/ghc/compiler/simplCore/SimplCore.lhs index bcfbbfa..8843455 100644 --- a/ghc/compiler/simplCore/SimplCore.lhs +++ b/ghc/compiler/simplCore/SimplCore.lhs @@ -8,39 +8,46 @@ module SimplCore ( core2core, simplifyExpr ) where #include "HsVersions.h" -import CmdLineOpts ( CoreToDo(..), SimplifierSwitch(..), - SwitchResult(..), intSwitchSet, - DynFlags, DynFlag(..), dopt, dopt_CoreToDo +import CmdLineOpts ( CoreToDo(..), SimplifierSwitch(..), + SimplifierMode(..), DynFlags, DynFlag(..), dopt, + dopt_CoreToDo, buildCoreToDo ) -import CoreLint ( showPass, endPass ) import CoreSyn -import CoreFVs ( ruleRhsFreeVars ) -import HscTypes ( PersistentCompilerState(..), - PackageRuleBase, HomeSymbolTable, IsExported, ModDetails(..) +import TcIface ( loadImportedRules ) +import HscTypes ( HscEnv(..), GhciMode(..), + ModGuts(..), ModGuts, Avails, + ModDetails(..), + HomeModInfo(..), ExternalPackageState(..), hscEPS ) import CSE ( cseProgram ) -import Rules ( RuleBase, emptyRuleBase, ruleBaseFVs, ruleBaseIds, - extendRuleBaseList, addRuleBaseFVs ) +import Rules ( RuleBase, emptyRuleBase, ruleBaseIds, + extendRuleBaseList, pprRuleBase, getLocalRules, + ruleCheckProgram ) import Module ( moduleEnvElts ) -import CoreUnfold -import PprCore ( pprCoreBindings, pprIdCoreRule, pprCoreExpr ) +import Name ( Name, isExternalName ) +import NameSet ( elemNameSet ) +import PprCore ( pprCoreBindings, pprCoreExpr, pprIdRules ) import OccurAnal ( occurAnalyseBinds, occurAnalyseGlobalExpr ) import CoreUtils ( coreBindsSize ) import Simplify ( simplTopBinds, simplExpr ) import SimplUtils ( simplBinders ) import SimplMonad -import ErrUtils ( dumpIfSet, dumpIfSet_dyn ) +import ErrUtils ( dumpIfSet, dumpIfSet_dyn, showPass ) +import CoreLint ( endPass ) import FloatIn ( floatInwards ) import FloatOut ( floatOutwards ) -import Id ( idName, isDataConWrapId, setIdNoDiscard, isLocalId ) +import Id ( idName, idIsFrom, idSpecialisation, setIdSpecialisation ) import VarSet import LiberateCase ( liberateCase ) import SAT ( doStaticArgs ) import Specialise ( specProgram) -import UsageSPInf ( doUsageSPInf ) -import StrictAnal ( saBinds ) +import SpecConstr ( specConstrProgram) +import DmdAnal ( dmdAnalPgm ) import WorkWrap ( wwTopBinds ) +#ifdef OLD_STRICTNESS +import StrictAnal ( saBinds ) import CprAnalyse ( cprAnalyse ) +#endif import UniqSupply ( UniqSupply, mkSplitUniqSupply, splitUniqSupply ) import IO ( hPutStr, stderr ) @@ -57,28 +64,27 @@ import List ( partition ) %************************************************************************ \begin{code} -core2core :: DynFlags -- includes spec of what core-to-core passes to do - -> PersistentCompilerState - -> HomeSymbolTable - -> IsExported - -> [CoreBind] -- Binds in - -> [IdCoreRule] -- Rules defined in this module - -> IO ([CoreBind], [IdCoreRule]) -- binds, local orphan rules out - -core2core dflags pcs hst is_exported binds rules +core2core :: HscEnv + -> ModGuts + -> IO ModGuts + +core2core hsc_env + mod_impl@(ModGuts { mg_binds = binds_in }) = do - let core_todos = dopt_CoreToDo dflags - let pkg_rule_base = pcs_rules pcs -- Rule-base accumulated from imported packages + let dflags = hsc_dflags hsc_env + core_todos + | Just todo <- dopt_CoreToDo dflags = todo + | otherwise = buildCoreToDo dflags us <- mkSplitUniqSupply 's' let (cp_us, ru_us) = splitUniqSupply us -- COMPUTE THE RULE BASE TO USE - (rule_base, local_rule_ids, orphan_rules, rule_rhs_fvs) - <- prepareRules dflags pkg_rule_base hst ru_us binds rules + (rule_base, local_rule_ids, orphan_rules) + <- prepareRules hsc_env mod_impl ru_us -- PREPARE THE BINDINGS - let binds1 = updateBinders local_rule_ids rule_rhs_fvs is_exported binds + let binds1 = updateBinders local_rule_ids binds_in -- DO THE BUSINESS (stats, processed_binds) @@ -91,33 +97,28 @@ core2core dflags pcs hst is_exported binds rules -- Return results -- We only return local orphan rules, i.e., local rules not attached to an Id -- The bindings cotain more rules, embedded in the Ids - return (processed_binds, orphan_rules) + return (mod_impl { mg_binds = processed_binds, mg_rules = orphan_rules}) simplifyExpr :: DynFlags -- includes spec of what core-to-core passes to do - -> PersistentCompilerState - -> HomeSymbolTable -> CoreExpr -> IO CoreExpr -- simplifyExpr is called by the driver to simplify an -- expression typed in at the interactive prompt -simplifyExpr dflags pcs hst expr +simplifyExpr dflags expr = do { ; showPass dflags "Simplify" ; us <- mkSplitUniqSupply 's' - ; let (expr', _counts) = initSmpl dflags sw_chkr us emptyVarSet black_list_all - (simplExprGently expr) + ; let env = emptySimplEnv SimplGently [] emptyVarSet + (expr', _counts) = initSmpl dflags us (simplExprGently env expr) ; dumpIfSet_dyn dflags Opt_D_dump_simpl "Simplified expression" (pprCoreExpr expr') ; return expr' } - where - sw_chkr any = SwBool False -- A bit bogus - black_list_all v = True -- Black list everything doCorePasses :: DynFlags @@ -139,8 +140,8 @@ doCorePasses dflags rb stats us binds (to_do : to_dos) doCorePasses dflags rb (stats `plusSimplCount` stats1) us2 binds1 to_dos -doCorePass dfs rb us binds (CoreDoSimplify sw_chkr) - = _scc_ "Simplify" simplifyPgm dfs rb sw_chkr us binds +doCorePass dfs rb us binds (CoreDoSimplify mode switches) + = _scc_ "Simplify" simplifyPgm dfs rb mode switches us binds doCorePass dfs rb us binds CoreCSE = _scc_ "CommonSubExpr" noStats dfs (cseProgram dfs binds) doCorePass dfs rb us binds CoreLiberateCase @@ -152,28 +153,44 @@ doCorePass dfs rb us binds (CoreDoFloatOutwards f) doCorePass dfs rb us binds CoreDoStaticArgs = _scc_ "StaticArgs" noStats dfs (doStaticArgs us binds) doCorePass dfs rb us binds CoreDoStrictness - = _scc_ "Stranal" noStats dfs (saBinds dfs binds) + = _scc_ "Stranal" noStats dfs (dmdAnalPgm dfs binds) doCorePass dfs rb us binds CoreDoWorkerWrapper = _scc_ "WorkWrap" noStats dfs (wwTopBinds dfs us binds) doCorePass dfs rb us binds CoreDoSpecialising = _scc_ "Specialise" noStats dfs (specProgram dfs us binds) -doCorePass dfs rb us binds CoreDoCPResult - = _scc_ "CPResult" noStats dfs (cprAnalyse dfs binds) +doCorePass dfs rb us binds CoreDoSpecConstr + = _scc_ "SpecConstr" noStats dfs (specConstrProgram dfs us binds) +#ifdef OLD_STRICTNESS +doCorePass dfs rb us binds CoreDoOldStrictness + = _scc_ "OldStrictness" noStats dfs (doOldStrictness dfs binds) +#endif doCorePass dfs rb us binds CoreDoPrintCore = _scc_ "PrintCore" noStats dfs (printCore binds) -doCorePass dfs rb us binds CoreDoUSPInf - = _scc_ "CoreUsageSPInf" noStats dfs (doUsageSPInf dfs us binds) doCorePass dfs rb us binds CoreDoGlomBinds = noStats dfs (glomBinds dfs binds) +doCorePass dfs rb us binds (CoreDoRuleCheck phase pat) + = noStats dfs (ruleCheck dfs phase pat binds) doCorePass dfs rb us binds CoreDoNothing = noStats dfs (return binds) +#ifdef OLD_STRICTNESS +doOldStrictness dfs binds + = do binds1 <- saBinds dfs binds + binds2 <- cprAnalyse dfs binds1 + return binds2 +#endif + printCore binds = do dumpIfSet True "Print Core" (pprCoreBindings binds) return binds +ruleCheck dflags phase pat binds = do showPass dflags "RuleCheck" + printDump (ruleCheckProgram phase pat binds) + return binds + -- most passes return no stats and don't change rules noStats dfs thing = do { binds <- thing; return (zeroSimplCount dfs, binds) } + \end{code} @@ -193,58 +210,52 @@ noStats dfs thing = do { binds <- thing; return (zeroSimplCount dfs, binds) } -- so that the opportunity to apply the rule isn't lost too soon \begin{code} -prepareRules :: DynFlags -> PackageRuleBase -> HomeSymbolTable +prepareRules :: HscEnv + -> ModGuts -> UniqSupply - -> [CoreBind] - -> [IdCoreRule] -- Local rules -> IO (RuleBase, -- Full rule base IdSet, -- Local rule Ids - [IdCoreRule], -- Orphan rules - IdSet) -- RHS free vars of all rules + [IdCoreRule]) -- Orphan rules defined in this module + +prepareRules hsc_env@(HscEnv { hsc_dflags = dflags, hsc_HPT = hpt }) + guts@(ModGuts { mg_binds = binds, mg_rules = local_rules, mg_module = this_mod }) + us + = do { pkg_rule_base <- loadImportedRules hsc_env guts -prepareRules dflags pkg_rule_base hst us binds rules - = do { let (better_rules,_) = initSmpl dflags sw_chkr us local_ids black_list_all - (mapSmpl simplRule rules) + ; let env = emptySimplEnv SimplGently [] local_ids + (better_rules,_) = initSmpl dflags us (mapSmpl (simplRule env) local_rules) + + imp_rule_base = foldl add_rules pkg_rule_base (moduleEnvElts hpt) + full_rule_base = extendRuleBaseList imp_rule_base better_rules + + (local_rule_ids, final_rule_base) = getLocalRules this_mod full_rule_base + -- NB: the imported rules may include rules for Ids in this module + -- which is why we suck the local rules out of full_rule_base + + orphan_rules = filter (not . idIsFrom this_mod . fst) better_rules ; dumpIfSet_dyn dflags Opt_D_dump_rules "Transformation rules" - (vcat (map pprIdCoreRule better_rules)) - - ; let (local_rules, orphan_rules) = partition (isLocalId . fst) better_rules - rule_rhs_fvs = unionVarSets (map (ruleRhsFreeVars . snd) better_rules) - local_rule_base = extendRuleBaseList emptyRuleBase local_rules - local_rule_ids = ruleBaseIds local_rule_base -- Local Ids with rules attached - imp_rule_base = foldl add_rules pkg_rule_base (moduleEnvElts hst) - rule_base = extendRuleBaseList imp_rule_base orphan_rules - final_rule_base = addRuleBaseFVs rule_base (ruleBaseFVs local_rule_base) - -- The last step black-lists the free vars of local rules too - ; return (final_rule_base, local_rule_ids, orphan_rules, rule_rhs_fvs) + (vcat [text "Local rules", pprIdRules better_rules, + text "", + text "Imported rules", pprRuleBase final_rule_base]) + + ; return (final_rule_base, local_rule_ids, orphan_rules) } where - sw_chkr any = SwBool False -- A bit bogus - black_list_all v = not (isDataConWrapId v) - -- This stops all inlining except the - -- wrappers for data constructors - - add_rules rule_base mds = extendRuleBaseList rule_base (md_rules mds) + add_rules rule_base mod_info = extendRuleBaseList rule_base (md_rules (hm_details mod_info)) -- Boringly, we need to gather the in-scope set. - -- Typically this thunk won't even be forced, but the test in - -- simpVar fails if it isn't right, and it might conceiveably matter local_ids = foldr (unionVarSet . mkVarSet . bindersOf) emptyVarSet binds updateBinders :: IdSet -- Locally defined ids with their Rules attached - -> IdSet -- Ids free in the RHS of local rules - -> IsExported -> [CoreBind] -> [CoreBind] -- A horrible function --- Update the binders of top-level bindings as follows --- a) Attach the rules for each locally-defined Id to that Id. --- b) Set the no-discard flag if either the Id is exported, --- or it's mentoined in the RHS of a rule +-- Update the binders of top-level bindings by +-- attaching the rules for each locally-defined Id to that Id. -- --- Reason for (a) +-- Reason -- - It makes the rules easier to look up -- - It means that transformation rules and specialisations for -- locally defined Ids are handled uniformly @@ -252,26 +263,16 @@ updateBinders :: IdSet -- Locally defined ids with their Rules attached -- (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 --- --- Reason for (b) --- It means that the binding won't be discarded EVEN if the binding --- ends up being trivial (v = w) -- the simplifier would usually just --- substitute w for v throughout, but we don't apply the substitution to --- the rules (maybe we should?), so this substitution would make the rule --- bogus. - -updateBinders rule_ids rule_rhs_fvs is_exported binds + +updateBinders rule_ids binds = map update_bndrs 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 - | is_exported (idName bndr) - || bndr `elemVarSet` rule_rhs_fvs = setIdNoDiscard bndr' - | otherwise = bndr' - where - bndr' = lookupVarSet rule_ids bndr `orElse` bndr + update_bndr bndr = case lookupVarSet rule_ids bndr of + Nothing -> bndr + Just id -> bndr `setIdSpecialisation` idSpecialisation id \end{code} @@ -282,13 +283,13 @@ which without simplification looked like: This doesn't match unless you do eta reduction on the build argument. \begin{code} -simplRule rule@(id, BuiltinRule _) +simplRule env rule@(id, BuiltinRule _ _) = returnSmpl rule -simplRule rule@(id, Rule name bndrs args rhs) - = simplBinders bndrs $ \ bndrs' -> - mapSmpl simplExprGently args `thenSmpl` \ args' -> - simplExprGently rhs `thenSmpl` \ rhs' -> - returnSmpl (id, Rule name bndrs' args' rhs') +simplRule env rule@(id, Rule act name bndrs args rhs) + = simplBinders env bndrs `thenSmpl` \ (env, bndrs') -> + mapSmpl (simplExprGently env) args `thenSmpl` \ args' -> + simplExprGently env rhs `thenSmpl` \ rhs' -> + returnSmpl (id, Rule act name bndrs' args' rhs') -- It's important that simplExprGently does eta reduction. -- For example, in a rule like: @@ -303,16 +304,21 @@ simplRule rule@(id, Rule name bndrs args rhs) \end{code} \begin{code} -simplExprGently :: CoreExpr -> SimplM CoreExpr +simplExprGently :: SimplEnv -> CoreExpr -> SimplM CoreExpr -- Simplifies an expression -- does occurrence analysis, then simplification -- and repeats (twice currently) because one pass -- alone leaves tons of crud. -- Used (a) for user expressions typed in at the interactive prompt -- (b) the LHS and RHS of a RULE -simplExprGently expr - = simplExpr (occurAnalyseGlobalExpr expr) `thenSmpl` \ expr1 -> - simplExpr (occurAnalyseGlobalExpr expr1) +-- +-- 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 + +simplExprGently env expr + = simplExpr env (occurAnalyseGlobalExpr expr) `thenSmpl` \ expr1 -> + simplExpr env (occurAnalyseGlobalExpr expr1) \end{code} @@ -367,13 +373,14 @@ glomBinds dflags binds \begin{code} simplifyPgm :: DynFlags -> RuleBase - -> (SimplifierSwitch -> SwitchResult) + -> SimplifierMode + -> [SimplifierSwitch] -> UniqSupply -> [CoreBind] -- Input -> IO (SimplCount, [CoreBind]) -- New bindings simplifyPgm dflags rule_base - sw_chkr us binds + mode switches us binds = do { showPass dflags "Simplify"; @@ -392,12 +399,33 @@ simplifyPgm dflags rule_base return (counts_out, binds') } where - max_iterations = getSimplIntSwitch sw_chkr MaxSimplifierIterations - black_list_fn = blackListed rule_lhs_fvs (intSwitchSet sw_chkr SimplInlinePhase) + phase_info = case mode of + SimplGently -> "gentle" + SimplPhase n -> show n + imported_rule_ids = ruleBaseIds rule_base - rule_lhs_fvs = ruleBaseFVs rule_base + simpl_env = emptySimplEnv mode switches imported_rule_ids + sw_chkr = getSwitchChecker simpl_env + max_iterations = intSwitchSet sw_chkr MaxSimplifierIterations `orElse` 2 iteration us iteration_no counts binds + -- 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.\n") + else + return (); +#endif + -- Subtract 1 from iteration_no to get the + -- number of iterations we actually completed + return ("Simplifier baled out", iteration_no - 1, counts, binds) + } + -- Try and force thunks off the binds; significantly reduces -- space usage, especially with -O. JRS, 000620. | let sz = coreBindsSize binds in sz == sz @@ -416,18 +444,21 @@ simplifyPgm dflags rule_base -- t = initSmpl ... -- counts' = snd t -- in - -- case t of {(_,counts') -> if counts'=0 then ... + -- case t of {(_,counts') -> if counts'=0 then ... } -- So the conditional didn't force counts', because the -- selection got duplicated. Sigh! - case initSmpl dflags sw_chkr us1 imported_rule_ids black_list_fn - (simplTopBinds tagged_binds) - of { (binds', counts') -> do { + case initSmpl dflags us1 (simplTopBinds simpl_env tagged_binds) of { + (binds', counts') -> do { -- The imported_rule_ids are used by initSmpl to initialise -- the in-scope set. That way, the simplifier will change any -- occurrences of the imported id to the one in the imported_rule_ids -- set, which are decorated with their rules. - let { all_counts = counts `plusSimplCount` counts' } ; + let { all_counts = counts `plusSimplCount` counts' ; + herald = "Simplifier phase " ++ phase_info ++ + ", iteration " ++ show iteration_no ++ + " out of " ++ show max_iterations + } ; -- Stop if nothing happened; don't dump output if isZeroSimplCount counts' then @@ -435,33 +466,13 @@ simplifyPgm dflags rule_base else do { -- Dump the result of this iteration - dumpIfSet_dyn dflags Opt_D_dump_simpl_iterations - ("Simplifier iteration " ++ show iteration_no - ++ " out of " ++ show max_iterations) - (pprSimplCount counts') ; - - endPass dflags - ("Simplifier iteration " ++ show iteration_no ++ " result") - Opt_D_dump_simpl_iterations - binds' ; - - -- Stop if we've run out of iterations - if iteration_no == max_iterations then - do { -#ifdef DEBUG - if max_iterations > 2 then - hPutStr stderr ("NOTE: Simplifier still going after " ++ - show max_iterations ++ - " iterations; bailing out.\n") - else -#endif - return (); + dumpIfSet_dyn dflags Opt_D_dump_simpl_iterations herald + (pprSimplCount counts') ; - return ("Simplifier baled out", iteration_no, all_counts, binds') - } + endPass dflags herald Opt_D_dump_simpl_iterations binds' ; - -- Else loop - else iteration us2 (iteration_no + 1) all_counts binds' + -- Loop + iteration us2 (iteration_no + 1) all_counts binds' } } } } where (us1, us2) = splitUniqSupply us