%
% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
%
-% $Id: CgClosure.lhs,v 1.26 1999/03/22 16:58:19 simonm Exp $
+% $Id: CgClosure.lhs,v 1.27 1999/04/08 15:46:15 simonm Exp $
%
\section[CgClosure]{Code generation for closures}
cl_descr mod_name = closureDescription mod_name (closureName closure_info)
body_label = entryLabelFromCI closure_info
+ is_box = case body of { StgApp fun [] -> True; _ -> False }
+
body_code = profCtrC SLIT("TICK_ENT_THK") [] `thenC`
thunkWrapper closure_info body_label (
-- We only enter cc after setting up update so that cc
-- of enclosing scope will be recorded in update frame
-- CAF/DICT functions will be subsumed by this enclosing cc
- enterCostCentreCode closure_info cc IsThunk `thenC`
+ enterCostCentreCode closure_info cc IsThunk is_box `thenC`
cgExpr body)
\end{code}
freeStackSlots (map fst stk_tags) `thenC`
-- Enter the closures cc, if required
- enterCostCentreCode closure_info cc IsFunction `thenC`
+ enterCostCentreCode closure_info cc IsFunction False `thenC`
-- Do the business
funWrapper closure_info arg_regs stk_tags slow_label (cgExpr body)
deriving Eq
-- #endif
-enterCostCentreCode :: ClosureInfo -> CostCentreStack -> IsThunk -> Code
+enterCostCentreCode
+ :: ClosureInfo -> CostCentreStack
+ -> IsThunk
+ -> Bool -- is_box: this closure is a special box introduced by SCCfinal
+ -> Code
-enterCostCentreCode closure_info ccs is_thunk
+enterCostCentreCode closure_info ccs is_thunk is_box
= if not opt_SccProfilingOn then
nopC
else
ASSERT(not (noCCSAttached ccs))
if isSubsumedCCS ccs then
- --ASSERT(isToplevClosure closure_info)
- --ASSERT(is_thunk == IsFunction)
- (if isToplevClosure closure_info && is_thunk == IsFunction then \x->x
- else pprTrace "enterCostCenterCode:" (hsep [ppr (is_thunk == IsFunction),
- ppr ccs])) $
+ ASSERT(isToplevClosure closure_info)
+ ASSERT(is_thunk == IsFunction)
costCentresC SLIT("ENTER_CCS_FSUB") []
+
+ else if isSetCurrentCCS ccs then
+ ASSERT(not (isToplevClosure closure_info))
+ ASSERT(is_thunk == IsFunction)
+ costCentresC SLIT("ENTER_CCS_TCL") [CReg node]
else if isCurrentCCS ccs then
- if re_entrant
+ if re_entrant && not is_box
then costCentresC SLIT("ENTER_CCS_FCL") [CReg node]
else costCentresC SLIT("ENTER_CCS_TCL") [CReg node]
- else if isCafCCS ccs && isToplevClosure closure_info then
+ else if isCafCCS ccs then
+ ASSERT(isToplevClosure closure_info)
ASSERT(is_thunk == IsThunk)
-- might be a PAP, in which case we want to subsume costs
if re_entrant
then costCentresC SLIT("ENTER_CCS_FSUB") []
else costCentresC SLIT("ENTER_CCS_CAF") c_ccs
- else -- we've got a "real" cost centre right here in our hands...
- case is_thunk of
- IsThunk -> costCentresC SLIT("ENTER_CCS_T") c_ccs
- IsFunction -> if isCafCCS ccs-- || isDictCC ccs
- then costCentresC SLIT("ENTER_CCS_FCAF") c_ccs
- else costCentresC SLIT("ENTER_CCS_FLOAD") c_ccs
+ else panic "enterCostCentreCode"
+
where
c_ccs = [mkCCostCentreStack ccs]
re_entrant = closureReEntrant closure_info
blame_cc -- cost-centre on whom we blame the allocation
= case (args, fvs, body) of
- ([], [just1], StgApp fun [{-no args-}])
- | just1 == fun
+ ([], _, StgApp fun [{-no args-}])
-> mkCCostCentreStack overheadCCS
_ -> use_cc
import CmdLineOpts ( opt_AutoSccsOnIndividualCafs )
import CostCentre -- lots of things
import Const ( Con(..) )
-import Id ( Id, mkSysLocal )
+import Id ( Id, mkSysLocal, idType, idName )
import Module ( Module )
import UniqSupply ( uniqFromSupply, splitUniqSupply, UniqSupply )
import Unique ( Unique )
+import Type ( splitForAllTys, splitTyConApp_maybe )
+import TyCon ( isFunTyCon )
+import VarSet
+import UniqSet
+import Name ( isLocallyDefinedName )
import Util ( removeDups )
import Outputable
= let
((local_ccs, extern_ccs, cc_stacks),
stg_binds2)
- = initMM mod_name us (mapMM do_top_binding stg_binds)
+ = initMM mod_name us (do_top_bindings stg_binds)
(fixed_ccs, fixed_cc_stacks)
= if opt_AutoSccsOnIndividualCafs
all_cafs_ccs = mkSingletonCCS all_cafs_cc
----------
- do_top_binding :: StgBinding -> MassageM StgBinding
+ do_top_bindings :: [StgBinding] -> MassageM [StgBinding]
- do_top_binding (StgNonRec b rhs)
- = do_top_rhs b rhs `thenMM` \ rhs' ->
- returnMM (StgNonRec b rhs')
+ do_top_bindings [] = returnMM []
- do_top_binding (StgRec pairs)
- = mapMM do_pair pairs `thenMM` \ pairs2 ->
- returnMM (StgRec pairs2)
+ do_top_bindings (StgNonRec b rhs : bs)
+ = do_top_rhs b rhs `thenMM` \ rhs' ->
+ addTopLevelIshId b (
+ do_top_bindings bs `thenMM` \bs' ->
+ returnMM (StgNonRec b rhs' : bs')
+ )
+
+ do_top_bindings (StgRec pairs : bs)
+ = addTopLevelIshIds binders (
+ mapMM do_pair pairs `thenMM` \ pairs2 ->
+ do_top_bindings bs `thenMM` \ bs' ->
+ returnMM (StgRec pairs2 : bs')
+ )
where
+ binders = map fst pairs
do_pair (b, rhs)
= do_top_rhs b rhs `thenMM` \ rhs2 ->
returnMM (b, rhs2)
returnMM ccs
else
returnMM all_cafs_ccs) `thenMM` \ caf_ccs ->
- set_prevailing_cc caf_ccs (do_expr body) `thenMM` \ body' ->
- returnMM (StgRhsClosure caf_ccs bi srt fv u [] body')
+ set_prevailing_cc caf_ccs (do_expr body) `thenMM` \ body' ->
+ returnMM (StgRhsClosure caf_ccs bi srt fv u [] body')
do_top_rhs binder (StgRhsClosure cc bi srt fv u [] body)
-- Top level CAF with cost centre attached
do_top_rhs binder (StgRhsClosure no_ccs bi srt fv u args body)
-- Top level function, probably subsumed
| noCCSAttached no_ccs
- = set_prevailing_cc currentCCS (do_expr body) `thenMM` \ body' ->
+ = set_lambda_cc (do_expr body) `thenMM` \ body' ->
returnMM (StgRhsClosure subsumedCCS bi srt fv u args body')
| otherwise
= boxHigherOrderArgs (\args -> StgCon con args res_ty) args
do_expr (StgSCC cc expr) -- Ha, we found a cost centre!
- = collectCC cc `thenMM_`
- set_prevailing_cc currentCCS (do_expr expr) `thenMM` \ expr' ->
+ = collectCC cc `thenMM_`
+ do_expr expr `thenMM` \ expr' ->
returnMM (StgSCC cc expr')
do_expr (StgCase expr fv1 fv2 bndr srt alts)
returnMM (StgBindDefault e')
do_expr (StgLet b e)
- = do_binding b `thenMM` \ b' ->
- do_expr e `thenMM` \ e' ->
- returnMM (StgLet b' e')
-
- do_expr (StgLetNoEscape lvs1 lvs2 rhs body)
- = do_binding rhs `thenMM` \ rhs' ->
- do_expr body `thenMM` \ body' ->
- returnMM (StgLetNoEscape lvs1 lvs2 rhs' body')
-
- ----------
- do_binding :: StgBinding -> MassageM StgBinding
-
- do_binding (StgNonRec b rhs)
- = do_rhs rhs `thenMM` \ rhs' ->
- returnMM (StgNonRec b rhs')
-
- do_binding (StgRec pairs)
- = mapMM do_pair pairs `thenMM` \ new_pairs ->
- returnMM (StgRec new_pairs)
+ = do_let b e `thenMM` \ (b,e) ->
+ returnMM (StgLet b e)
+
+ do_expr (StgLetNoEscape lvs1 lvs2 b e)
+ = do_let b e `thenMM` \ (b,e) ->
+ returnMM (StgLetNoEscape lvs1 lvs2 b e)
+
+ ----------------------------------
+
+ do_let (StgNonRec b rhs) e
+ = do_rhs rhs `thenMM` \ rhs' ->
+ addTopLevelIshId b (
+ do_expr e `thenMM` \ e' ->
+ returnMM (StgNonRec b rhs',e')
+ )
+
+ do_let (StgRec pairs) e
+ = addTopLevelIshIds binders (
+ mapMM do_pair pairs `thenMM` \ pairs' ->
+ do_expr e `thenMM` \ e' ->
+ returnMM (StgRec pairs', e')
+ )
where
- do_pair (b, rhs)
- = do_rhs rhs `thenMM` \ rhs' ->
- returnMM (b, rhs')
+ binders = map fst pairs
+ do_pair (b, rhs)
+ = do_rhs rhs `thenMM` \ rhs2 ->
+ returnMM (b, rhs2)
+ ----------------------------------
do_rhs :: StgRhs -> MassageM StgRhs
-- We play much the same game as we did in do_top_rhs above;
-- but we don't have to worry about cafs etc.
returnMM (StgRhsClosure cc bi srt fv u args expr')
-}
+ do_rhs (StgRhsClosure cc bi srt fv u [] body)
+ = do_expr body `thenMM` \ body' ->
+ returnMM (StgRhsClosure currentCCS bi srt fv u [] body')
+
do_rhs (StgRhsClosure cc bi srt fv u args body)
- = set_prevailing_cc_maybe cc $ \ cc' ->
- set_lambda_cc (do_expr body) `thenMM` \ body' ->
- returnMM (StgRhsClosure cc' bi srt fv u args body')
+ = set_lambda_cc (do_expr body) `thenMM` \ body' ->
+ get_prevailing_cc `thenMM` \ prev_ccs ->
+ let new_ccs | isCurrentCCS prev_ccs = setCurrentCCS -- are we inside a lambda??
+ | otherwise = currentCCS
+ in
+ returnMM (StgRhsClosure new_ccs bi srt fv u args body')
do_rhs (StgRhsCon cc con args)
- = set_prevailing_cc_maybe cc $ \ cc' ->
- returnMM (StgRhsCon cc' con args)
-
- -- ToDo: Box args and sort out any let bindings ???
- -- Nope: maybe later? WDP 94/06
+ = returnMM (StgRhsCon currentCCS con args)
\end{code}
%************************************************************************
\begin{code}
boxHigherOrderArgs
:: ([StgArg] -> StgExpr)
- -- An application lacking its arguments and live-var info
+ -- An application lacking its arguments
-> [StgArg] -- arguments which we might box
-> MassageM StgExpr
boxHigherOrderArgs almost_expr args
- = returnMM (almost_expr args)
-
-{- No boxing for now ... should be moved to desugarer and preserved ...
-
-boxHigherOrderArgs almost_expr args live_vars
- = get_prevailing_cc `thenMM` \ cc ->
- if (isCafCC cc || isDictCC cc) then
- -- no boxing required inside CAF/DICT cc
- -- since CAF/DICT functions are subsumed anyway
- returnMM (almost_expr args live_vars)
- else
- mapAccumMM do_arg [] args `thenMM` \ (let_bindings, new_args) ->
- returnMM (foldr (mk_stg_let cc) (almost_expr new_args live_vars) let_bindings)
+ = getTopLevelIshIds `thenMM` \ ids ->
+ mapAccumMM (do_arg ids) [] args `thenMM` \ (let_bindings, new_args) ->
+ returnMM (foldr (mk_stg_let currentCCS) (almost_expr new_args) let_bindings)
where
---------------
- do_arg bindings atom@(StgLitAtom _) = returnMM (bindings, atom)
+ do_arg ids bindings atom@(StgConArg _) = returnMM (bindings, atom)
- do_arg bindings atom@(StgVarAtom old_var)
+ do_arg ids bindings atom@(StgVarArg old_var)
= let
- var_type = getIdUniType old_var
+ var_type = idType old_var
in
- if toplevelishId old_var && isFunType (getTauType var_type)
+ if ( not (isLocallyDefinedName (idName old_var)) ||
+ elemVarSet old_var ids ) && isFunType var_type
then
-- make a trivial let-binding for the top-level function
getUniqueMM `thenMM` \ uniq ->
let
new_var = mkSysLocal SLIT("sf") uniq var_type
in
- returnMM ( (new_var, old_var) : bindings, StgVarAtom new_var )
+ returnMM ( (new_var, old_var) : bindings, StgVarArg new_var )
else
returnMM (bindings, atom)
---------------
- mk_stg_let :: CostCentre -> (Id, Id) -> StgExpr -> StgExpr
+ mk_stg_let :: CostCentreStack -> (Id, Id) -> StgExpr -> StgExpr
mk_stg_let cc (new_var, old_var) body
= let
- rhs_body = StgApp (StgVarAtom old_var) [{-args-}]
+ rhs_body = StgApp old_var [{-args-}]
rhs_closure = StgRhsClosure cc stgArgOcc NoSRT [{-fvs-}] ReEntrant [{-args-}] rhs_body
in
StgLet (StgNonRec new_var rhs_closure) body
where
bOGUS_LVs = emptyUniqSet -- easier to print than: panic "mk_stg_let: LVs"
--}
+
+isFunType var_type
+ = case splitForAllTys var_type of
+ (_, ty) -> case splitTyConApp_maybe ty of
+ Just (tycon,_) | isFunTyCon tycon -> True
+ _ -> False
+
\end{code}
%************************************************************************
-- if none, subsumedCosts at top-level
-- useCurrentCostCentre at nested levels
-> UniqSupply
+ -> VarSet -- toplevel-ish Ids for boxing
-> CollectedCCs
-> (CollectedCCs, result)
-> MassageM a
-> (CollectedCCs, a)
-initMM mod_name init_us m = m mod_name noCCS init_us ([],[],[])
+initMM mod_name init_us m = m mod_name noCCS init_us emptyVarSet ([],[],[])
thenMM :: MassageM a -> (a -> MassageM b) -> MassageM b
thenMM_ :: MassageM a -> (MassageM b) -> MassageM b
-thenMM expr cont mod scope_cc us ccs
+thenMM expr cont mod scope_cc us ids ccs
= case splitUniqSupply us of { (s1, s2) ->
- case (expr mod scope_cc s1 ccs) of { (ccs2, result) ->
- cont result mod scope_cc s2 ccs2 }}
+ case (expr mod scope_cc s1 ids ccs) of { (ccs2, result) ->
+ cont result mod scope_cc s2 ids ccs2 }}
-thenMM_ expr cont mod scope_cc us ccs
+thenMM_ expr cont mod scope_cc us ids ccs
= case splitUniqSupply us of { (s1, s2) ->
- case (expr mod scope_cc s1 ccs) of { (ccs2, _) ->
- cont mod scope_cc s2 ccs2 }}
+ case (expr mod scope_cc s1 ids ccs) of { (ccs2, _) ->
+ cont mod scope_cc s2 ids ccs2 }}
returnMM :: a -> MassageM a
-returnMM result mod scope_cc us ccs = (ccs, result)
+returnMM result mod scope_cc us ids ccs = (ccs, result)
nopMM :: MassageM ()
-nopMM mod scope_cc us ccs = (ccs, ())
+nopMM mod scope_cc us ids ccs = (ccs, ())
mapMM :: (a -> MassageM b) -> [a] -> MassageM [b]
-
mapMM f [] = returnMM []
mapMM f (m:ms)
= f m `thenMM` \ r ->
returnMM (r:rs)
mapAccumMM :: (acc -> x -> MassageM (acc, y)) -> acc -> [x] -> MassageM (acc, [y])
-
mapAccumMM f b [] = returnMM (b, [])
mapAccumMM f b (m:ms)
= f b m `thenMM` \ (b2, r) ->
returnMM (b3, r:rs)
getUniqueMM :: MassageM Unique
-getUniqueMM mod scope_cc us ccs = (ccs, uniqFromSupply us)
-\end{code}
+getUniqueMM mod scope_cc us ids ccs = (ccs, uniqFromSupply us)
-I'm not sure about all this prevailing CC stuff --SDM
+addTopLevelIshId :: Id -> MassageM a -> MassageM a
+addTopLevelIshId id scope mod scope_cc us ids ccs
+ | isCurrentCCS scope_cc = scope mod scope_cc us ids ccs
+ | otherwise = scope mod scope_cc us (extendVarSet ids id) ccs
-\begin{code}
-set_prevailing_cc :: CostCentreStack -> MassageM a -> MassageM a
-set_prevailing_cc cc_to_set_to action mod scope_cc us ccs
- -- set unconditionally
- = action mod cc_to_set_to us ccs
+addTopLevelIshIds :: [Id] -> MassageM a -> MassageM a
+addTopLevelIshIds [] cont = cont
+addTopLevelIshIds (id:ids) cont
+ = addTopLevelIshId id (addTopLevelIshIds ids cont)
-set_prevailing_cc_maybe :: CostCentreStack -> (CostCentreStack -> MassageM a) -> MassageM a
-set_prevailing_cc_maybe cc_to_try action mod scope_cc us ccs
- -- set only if a real cost centre
- = let
- cc_to_use
- = if noCCSAttached cc_to_try
- then scope_cc -- carry on as before
- else cc_to_try -- use new cost centre
- in
- action cc_to_use mod cc_to_use us ccs
+getTopLevelIshIds :: MassageM VarSet
+getTopLevelIshIds mod scope_cc us ids ccs = (ccs, ids)
+\end{code}
+
+The prevailing CCS is used to tell whether we're in a top-levelish
+position, where top-levelish is defined as "not inside a lambda".
+Prevailing CCs used to be used for something much more complicated,
+I'm sure --SDM
+\begin{code}
set_lambda_cc :: MassageM a -> MassageM a
-set_lambda_cc action mod scope_cc us ccs
- -- used when moving inside a lambda;
- -- if we were chugging along as "caf/dict" we change to "ccc"
- = let
- cc_to_use = currentCCS
- {-
- = if isCafCC scope_cc || isDictCC scope_cc
- then useCurrentCostCentre
- else scope_cc
- -}
- in
- action mod cc_to_use us ccs
+set_lambda_cc action mod scope_cc us ids ccs
+ = action mod currentCCS us ids ccs
+set_prevailing_cc :: CostCentreStack -> MassageM a -> MassageM a
+set_prevailing_cc cc_to_set_to action mod scope_cc us ids ccs
+ = action mod cc_to_set_to us ids ccs
get_prevailing_cc :: MassageM CostCentreStack
-get_prevailing_cc mod scope_cc us ccs = (ccs, scope_cc)
-
+get_prevailing_cc mod scope_cc us ids ccs = (ccs, scope_cc)
\end{code}
\begin{code}
collectCC :: CostCentre -> MassageM ()
-collectCC cc mod_name scope_cc us (local_ccs, extern_ccs, ccss)
+collectCC cc mod_name scope_cc us ids (local_ccs, extern_ccs, ccss)
= ASSERT(not (noCCAttached cc))
if (cc `ccFromThisModule` mod_name) then
((cc : local_ccs, extern_ccs, ccss), ())
collectCCS :: CostCentreStack -> MassageM ()
-collectCCS ccs mod_name scope_cc us (local_ccs, extern_ccs, ccss)
+collectCCS ccs mod_name scope_cc us ids (local_ccs, extern_ccs, ccss)
= ASSERT(not (noCCSAttached ccs))
((local_ccs, extern_ccs, ccs : ccss), ())
\end{code}
projects / ghc-hetmet.git / commitdiff