\section[SimplCore]{Driver for simplifying @Core@ programs}
\begin{code}
-module SimplCore ( core2core ) where
+module SimplCore ( core2core, simplifyExpr ) where
#include "HsVersions.h"
import CoreLint ( showPass, endPass )
import CoreSyn
import CoreFVs ( ruleRhsFreeVars )
-import HscTypes ( PackageRuleBase, HomeSymbolTable, IsExported, ModDetails(..) )
+import HscTypes ( PersistentCompilerState(..),
+ PackageRuleBase, HomeSymbolTable, IsExported, ModDetails(..)
+ )
import CSE ( cseProgram )
import Rules ( RuleBase, emptyRuleBase, ruleBaseFVs, ruleBaseIds,
extendRuleBaseList, addRuleBaseFVs )
import Module ( moduleEnvElts )
import CoreUnfold
-import PprCore ( pprCoreBindings, pprIdCoreRule )
-import OccurAnal ( occurAnalyseBinds )
-import CoreUtils ( etaReduceExpr, coreBindsSize )
+import PprCore ( pprCoreBindings, pprIdCoreRule, pprCoreExpr )
+import OccurAnal ( occurAnalyseBinds, occurAnalyseGlobalExpr )
+import CoreUtils ( coreBindsSize )
import Simplify ( simplTopBinds, simplExpr )
import SimplUtils ( simplBinders )
import SimplMonad
import LiberateCase ( liberateCase )
import SAT ( doStaticArgs )
import Specialise ( specProgram)
+import SpecConstr ( specConstrProgram)
import UsageSPInf ( doUsageSPInf )
import StrictAnal ( saBinds )
import WorkWrap ( wwTopBinds )
\begin{code}
core2core :: DynFlags -- includes spec of what core-to-core passes to do
- -> PackageRuleBase -- Rule-base accumulated from imported packages
+ -> PersistentCompilerState
-> HomeSymbolTable
-> IsExported
-> [CoreBind] -- Binds in
- -> [IdCoreRule] -- Rules in
+ -> [IdCoreRule] -- Rules defined in this module
-> IO ([CoreBind], [IdCoreRule]) -- binds, local orphan rules out
-core2core dflags pkg_rule_base hst is_exported binds rules
+core2core dflags pcs hst is_exported binds rules
= do
- let core_todos = dopt_CoreToDo dflags
+ let core_todos = dopt_CoreToDo dflags
+ let pkg_rule_base = pcs_rules pcs -- Rule-base accumulated from imported packages
+
us <- mkSplitUniqSupply 's'
let (cp_us, ru_us) = splitUniqSupply us
-- COMPUTE THE RULE BASE TO USE
- (rule_base, local_rule_stuff, orphan_rules)
+ (rule_base, local_rule_ids, orphan_rules, rule_rhs_fvs)
<- prepareRules dflags pkg_rule_base hst ru_us binds rules
-- PREPARE THE BINDINGS
- let binds1 = updateBinders local_rule_stuff is_exported binds
+ let binds1 = updateBinders local_rule_ids rule_rhs_fvs is_exported binds
-- DO THE BUSINESS
(stats, processed_binds)
return (processed_binds, 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
+ = do {
+ ; showPass dflags "Simplify"
+
+ ; us <- mkSplitUniqSupply 's'
+
+ ; let (expr', _counts) = initSmpl dflags sw_chkr us emptyVarSet black_list_nothing
+ (simplExprGently 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_nothing v = False -- Black list nothing
+
+
doCorePasses :: DynFlags
-> RuleBase -- the main rule base
-> SimplCount -- simplifier stats
= _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 CoreDoSpecConstr
+ = _scc_ "SpecConstr" noStats dfs (specConstrProgram dfs us binds)
doCorePass dfs rb us binds CoreDoCPResult
= _scc_ "CPResult" noStats dfs (cprAnalyse dfs binds)
doCorePass dfs rb us binds CoreDoPrintCore
-> [CoreBind]
-> [IdCoreRule] -- Local rules
-> IO (RuleBase, -- Full rule base
- (IdSet,IdSet), -- Local rule Ids, and RHS fvs
- [IdCoreRule]) -- Orphan rules
+ IdSet, -- Local rule Ids
+ [IdCoreRule], -- Orphan rules
+ IdSet) -- RHS free vars of all rules
prepareRules dflags pkg_rule_base hst us binds rules
= do { let (better_rules,_) = initSmpl dflags sw_chkr us local_ids black_list_all
(vcat (map pprIdCoreRule better_rules))
; let (local_rules, orphan_rules) = partition (isLocalId . fst) better_rules
- local_rule_rhs_fvs = unionVarSets (map (ruleRhsFreeVars . snd) local_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, local_rule_rhs_fvs), orphan_rules)
+ ; return (final_rule_base, local_rule_ids, orphan_rules, rule_rhs_fvs)
}
where
sw_chkr any = SwBool False -- A bit bogus
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
+updateBinders :: IdSet -- Locally defined ids with their Rules attached
+ -> IdSet -- Ids free in the RHS of local rules
-> IsExported
-> [CoreBind] -> [CoreBind]
-- A horrible function
-- 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 rule_rhs_fvs is_exported binds
= map update_bndrs binds
where
update_bndrs (NonRec b r) = NonRec (update_bndr b) r
= returnSmpl rule
simplRule rule@(id, Rule name bndrs args rhs)
= simplBinders bndrs $ \ bndrs' ->
- mapSmpl simpl_arg args `thenSmpl` \ args' ->
- simplExpr rhs `thenSmpl` \ rhs' ->
+ mapSmpl simplExprGently args `thenSmpl` \ args' ->
+ simplExprGently rhs `thenSmpl` \ rhs' ->
returnSmpl (id, Rule name bndrs' args' rhs')
-simpl_arg e
--- I've seen rules in which a LHS like
+-- It's important that simplExprGently does eta reduction.
+-- For example, in a rule like:
-- augment g (build h)
--- turns into
+-- we do not want to get
-- augment (\a. g a) (build h)
--- So it's a help to eta-reduce the args as we simplify them.
--- Otherwise we don't match when given an argument like
+-- otherwise we don't match when given an argument like
-- (\a. h a a)
- = simplExpr e `thenSmpl` \ e' ->
- returnSmpl (etaReduceExpr e')
+--
+-- The simplifier does indeed do eta reduction (it's in
+-- Simplify.completeLam) but only if -O is on.
+\end{code}
+
+\begin{code}
+simplExprGently :: 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)
\end{code}
text "",
pprSimplCount counts_out]);
- endPass dflags "Simplify"
- (dopt Opt_D_verbose_core2core dflags
- && not (dopt Opt_D_dump_simpl_iterations dflags))
- binds' ;
+ endPass dflags "Simplify" Opt_D_verbose_core2core binds';
return (counts_out, binds')
}
++ " out of " ++ show max_iterations)
(pprSimplCount counts') ;
- if dopt Opt_D_dump_simpl_iterations dflags then
- endPass dflags
- ("Simplifier iteration " ++ show iteration_no ++ " result")
- (dopt Opt_D_verbose_core2core dflags)
- binds'
- else
- return [] ;
+ 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