%
-% (c) The GRASP/AQUA Project, Glasgow University, 1993-1995
+% (c) The GRASP/AQUA Project, Glasgow University, 1993-1998
%
\section[SimplStg]{Driver for simplifying @STG@ programs}
\begin{code}
-#include "HsVersions.h"
-
module SimplStg ( stg2stg ) where
-IMP_Ubiq(){-uitous-}
-IMPORT_1_3(IO(hPutStr,stderr))
+#include "HsVersions.h"
import StgSyn
import LambdaLift ( liftProgram )
-import Name ( isLocallyDefined )
-import UniqSet ( UniqSet(..), mapUniqSet )
-import CostCentre ( CostCentre )
+import CostCentre ( CostCentre, CostCentreStack )
import SCCfinal ( stgMassageForProfiling )
import StgLint ( lintStgBindings )
import StgStats ( showStgStats )
import StgVarInfo ( setStgVarInfo )
import UpdAnal ( updateAnalyse )
+import SRT ( computeSRTs )
-import CmdLineOpts ( opt_SccGroup, --Not used:opt_EnsureSplittableC,
+import CmdLineOpts ( opt_SccGroup,
opt_StgDoLetNoEscapes, opt_D_verbose_stg2stg,
opt_DoStgLinting,
StgToDo(..)
)
-import Id ( nullIdEnv, lookupIdEnv, addOneToIdEnv,
- growIdEnvList, isNullIdEnv, SYN_IE(IdEnv),
- setIdVisibility,
- GenId{-instance Eq/Outputable -}, SYN_IE(Id)
- )
-import Maybes ( maybeToBool )
-import PprType ( GenType{-instance Outputable-} )
-import Outputable ( PprStyle, Outputable(..) )
-import Pretty ( Doc, ($$), vcat, text, ptext )
+import Id ( Id )
+import VarEnv
+import ErrUtils ( doIfSet )
import UniqSupply ( splitUniqSupply, UniqSupply )
-import Util ( mapAccumL, panic, assertPanic )
+import Util ( panic, assertPanic, trace )
+import IO ( hPutStr, stderr )
+import Outputable
\end{code}
\begin{code}
stg2stg :: [StgToDo] -- spec of what stg-to-stg passes to do
-> FAST_STRING -- module name (profiling only)
- -> PprStyle -- printing style (for debugging only)
-> UniqSupply -- a name supply
-> [StgBinding] -- input...
-> IO
- ([StgBinding], -- output program...
- ([CostCentre], -- local cost-centres that need to be decl'd
- [CostCentre])) -- "extern" cost-centres
+ ([(StgBinding,[Id])], -- output program...
+ ([CostCentre], -- local cost-centres that need to be decl'd
+ [CostCentre], -- "extern" cost-centres
+ [CostCentreStack])) -- pre-defined "singleton" cost centre stacks
-stg2stg stg_todos module_name ppr_style us binds
+stg2stg stg_todos module_name us binds
= case (splitUniqSupply us) of { (us4now, us4later) ->
- (if do_verbose_stg2stg then
- hPutStr stderr "VERBOSE STG-TO-STG:\n" >>
- hPutStr stderr (show
- (($$) (ptext SLIT("*** Core2Stg:"))
- (vcat (map (ppr ppr_style) (setStgVarInfo False binds)))
- ))
- else return ()) >>
+ doIfSet do_verbose_stg2stg
+ (printErrs (text "VERBOSE STG-TO-STG:" $$
+ text "*** Core2Stg:" $$
+ vcat (map ppr (setStgVarInfo False binds)))) >>
-- Do the main business!
- foldl_mn do_stg_pass (binds, us4now, ([],[])) stg_todos
+ foldl_mn do_stg_pass (binds, us4now, ([],[],[])) stg_todos
>>= \ (processed_binds, _, cost_centres) ->
-- Do essential wind-up
-{- Nuked for now SLPJ Dec 96
-
- -- Essential wind-up: part (a), saturate RHSs
- -- This must occur *after* elimIndirections, because elimIndirections
- -- can change things' arities. Consider:
- -- x_local = f x
- -- x_global = \a -> x_local a
- -- Then elimIndirections will change the program to
- -- x_global = f x
- -- and lo and behold x_global's arity has changed!
- case (satStgRhs processed_binds us4later) of { saturated_binds ->
--}
-
-- Essential wind-up: part (b), do setStgVarInfo. It has to
-- happen regardless, because the code generator uses its
-- decorations.
-- correct, which is done by satStgRhs.
--
-{-
- Done in Core now. Nuke soon. SLPJ Nov 96
-
- No, STG passes may introduce toplevel bindings which
- have to be globalised here (later than Core anyway) -- SOF 2/97
-
- Yes, lambda lifting now does the Right Thing.
-
let
- -- ToDo: provide proper flag control!
- binds_to_mangle
- = if not do_unlocalising
- then processed_binds
- else snd (unlocaliseStgBinds unlocal_tag nullIdEnv processed_binds)
+ annotated_binds = setStgVarInfo do_let_no_escapes processed_binds
+ srt_binds = computeSRTs annotated_binds
in
--}
- return (setStgVarInfo do_let_no_escapes processed_binds, cost_centres)
+ return (srt_binds, cost_centres)
}
where
do_let_no_escapes = opt_StgDoLetNoEscapes
do_verbose_stg2stg = opt_D_verbose_stg2stg
-{-
- (do_unlocalising, unlocal_tag)
- = case opt_EnsureSplittableC of
- Just tag -> (True, _PK_ tag)
- Nothing -> (False, panic "tag")
--}
grp_name = case (opt_SccGroup) of
Just xx -> _PK_ xx
Nothing -> module_name -- default: module name
-------------
- stg_linter = if False --LATER: opt_DoStgLinting (ToDo)
- then lintStgBindings ppr_style
+ stg_linter = if opt_DoStgLinting
+ then lintStgBindings
else ( \ whodunnit binds -> binds )
-------------------------------------------
StgDoStaticArgs -> panic "STG static argument transformation deleted"
StgDoUpdateAnalysis ->
- ASSERT(null (fst ccs) && null (snd ccs))
_scc_ "StgUpdAnal"
-- NB We have to do setStgVarInfo first! (There's one
-- place free-var info is used) But no let-no-escapes,
= -- report verbosely, if required
(if do_verbose_stg2stg then
hPutStr stderr (show
- (($$) (text ("*** "++what++":"))
- (vcat (map (ppr ppr_style) binds2))
+ (text ("*** "++what++":") $$ vcat (map ppr binds2)
))
else return ()) >>
let
foldl_mn f z (x:xs) = f z x >>= \ zz ->
foldl_mn f zz xs
\end{code}
-
-%************************************************************************
-%* *
-\subsection[SimplStg-unlocalise]{Unlocalisation in STG code}
-%* *
-%************************************************************************
-
-The idea of all this ``unlocalise'' stuff is that in certain (prelude
-only) modules we split up the .hc file into lots of separate little
-files, which are separately compiled by the C compiler. That gives
-lots of little .o files. The idea is that if you happen to mention
-one of them you don't necessarily pull them all in. (Pulling in a
-piece you don't need can be v bad, because it may mention other pieces
-you don't need either, and so on.)
-
-Sadly, splitting up .hc files means that local names (like s234) are
-now globally visible, which can lead to clashes between two .hc
-files. So unlocaliseWhatnot goes through making all the local things
-into global things, essentially by giving them full names so when they
-are printed they'll have their module name too. Pretty revolting
-really.
-
-\begin{code}
-type UnlocalEnv = IdEnv Id
-
-lookup_uenv :: UnlocalEnv -> Id -> Id
-lookup_uenv env id = case lookupIdEnv env id of
- Nothing -> id
- Just new_id -> new_id
-unlocaliseStgBinds :: FAST_STRING
- -> UnlocalEnv
- -> [StgBinding]
- -> (UnlocalEnv, [StgBinding])
-unlocaliseStgBinds mod uenv [] = (uenv, [])
-unlocaliseStgBinds mod uenv (b : bs) =
- case unlocal_top_bind mod uenv b of { (new_uenv, new_b) ->
- case unlocaliseStgBinds mod new_uenv bs of { (uenv3, new_bs) ->
- (uenv3, new_b : new_bs)
- }}
-
-------------------
-unlocal_top_bind :: FAST_STRING
- -> UnlocalEnv
- -> StgBinding
- -> (UnlocalEnv, StgBinding)
-unlocal_top_bind mod uenv bind@(StgNonRec binder _) =
- let
- new_uenv =
- case lookupIdEnv uenv binder of
- Just global -> uenv
- Nothing -> new_env
- where
- new_env = addOneToIdEnv uenv binder new_global
- new_global = setIdVisibility mod binder
- in
- (new_uenv, renameTopStgBind (lookup_uenv new_uenv) bind)
-
-unlocal_top_bind mod uenv bind@(StgRec pairs) =
- let
- new_env binder uenv =
- case lookupIdEnv uenv binder of
- Just global -> uenv
- Nothing -> env'
- where
- env' = addOneToIdEnv uenv binder new_global
- new_global = setIdVisibility mod binder
-
- uenv' = foldr (new_env) uenv (map (fst) pairs)
- in
- (uenv', renameTopStgBind (lookup_uenv uenv') bind)
-
-\end{code}
-
-@renameTopStgBind@ renames top level binders and all occurrences thereof.
-
-\begin{code}
-renameTopStgBind :: (Id -> Id) -> StgBinding -> StgBinding
-renameTopStgBind fn (StgNonRec b rhs) = StgNonRec (fn b) (mapStgBindeesRhs fn rhs)
-renameTopStgBind fn (StgRec pairs) = StgRec [ (fn b, mapStgBindeesRhs fn r) | (b, r) <- pairs ]
-\end{code}
-
-This utility function simply applies the given function to every
-bindee in the program.
-
-\begin{code}
-mapStgBindeesBind :: (Id -> Id) -> StgBinding -> StgBinding
-mapStgBindeesBind fn (StgNonRec b rhs) = StgNonRec b (mapStgBindeesRhs fn rhs)
-mapStgBindeesBind fn (StgRec pairs) = StgRec [ (b, mapStgBindeesRhs fn r) | (b, r) <- pairs ]
-
-------------------
-mapStgBindeesRhs :: (Id -> Id) -> StgRhs -> StgRhs
-mapStgBindeesRhs fn (StgRhsClosure cc bi fvs u args expr)
- = StgRhsClosure
- cc bi
- (map fn fvs)
- u
- (map fn args)
- (mapStgBindeesExpr fn expr)
-
-mapStgBindeesRhs fn (StgRhsCon cc con atoms)
- = StgRhsCon cc con (map (mapStgBindeesArg fn) atoms)
-
-------------------
-mapStgBindeesExpr :: (Id -> Id) -> StgExpr -> StgExpr
-
-mapStgBindeesExpr fn (StgApp f args lvs)
- = StgApp (mapStgBindeesArg fn f)
- (map (mapStgBindeesArg fn) args)
- (mapUniqSet fn lvs)
-
-mapStgBindeesExpr fn (StgCon con atoms lvs)
- = StgCon con (map (mapStgBindeesArg fn) atoms) (mapUniqSet fn lvs)
-
-mapStgBindeesExpr fn (StgPrim op atoms lvs)
- = StgPrim op (map (mapStgBindeesArg fn) atoms) (mapUniqSet fn lvs)
-
-mapStgBindeesExpr fn (StgLet bind expr)
- = StgLet (mapStgBindeesBind fn bind) (mapStgBindeesExpr fn expr)
-
-mapStgBindeesExpr fn (StgLetNoEscape lvs rhss_lvs bind body)
- = StgLetNoEscape (mapUniqSet fn lvs) (mapUniqSet fn rhss_lvs)
- (mapStgBindeesBind fn bind) (mapStgBindeesExpr fn body)
-
-mapStgBindeesExpr fn (StgSCC ty label expr)
- = StgSCC ty label (mapStgBindeesExpr fn expr)
-
-mapStgBindeesExpr fn (StgCase expr lvs1 lvs2 uniq alts)
- = StgCase (mapStgBindeesExpr fn expr)
- (mapUniqSet fn lvs1)
- (mapUniqSet fn lvs2)
- uniq
- (mapStgBindeesAlts alts)
- where
- mapStgBindeesAlts (StgAlgAlts ty alts deflt)
- = StgAlgAlts ty (map mapStgBindeesBoxed_alt alts) (mapStgBindeesDeflt deflt)
- where
- mapStgBindeesBoxed_alt (c,ps,use_mask,expr) = (c,ps,use_mask,mapStgBindeesExpr fn expr)
-
- mapStgBindeesAlts (StgPrimAlts ty alts deflt)
- = StgPrimAlts ty (map mapStgBindeesunboxed_alt alts) (mapStgBindeesDeflt deflt)
- where
- mapStgBindeesunboxed_alt (l,expr) = (l,mapStgBindeesExpr fn expr)
-
- mapStgBindeesDeflt StgNoDefault = StgNoDefault
- mapStgBindeesDeflt (StgBindDefault b used expr) = StgBindDefault b used (mapStgBindeesExpr fn expr)
-
-------------------
-mapStgBindeesArg :: (Id -> Id) -> StgArg -> StgArg
-mapStgBindeesArg fn a@(StgLitArg _) = a
-mapStgBindeesArg fn a@(StgConArg _) = a
-mapStgBindeesArg fn a@(StgVarArg id) = StgVarArg (fn id)
-\end{code}
projects / ghc-hetmet.git / blobdiff