%
-% (c) The GRASP/AQUA Project, Glasgow University, 1992-1995
+% (c) The GRASP/AQUA Project, Glasgow University, 1992-1996
%
-\section[SCCfinal]{Modify and collect code generation for final StgProgram}
+\section[SCCfinal]{Modify and collect code generation for final STG program}
This is now a sort-of-normal STG-to-STG pass (WDP 94/06), run by stg2stg.
* "Distributes" given cost-centres to all as-yet-unmarked RHSs.
\begin{code}
-#include "HsVersions.h"
-
module SCCfinal ( stgMassageForProfiling ) where
-import Pretty -- ToDo: rm (debugging only)
+#include "HsVersions.h"
-import AbsUniType ( isDictTy, getUniDataTyCon_maybe,
- isTupleTyCon, isFunType, getTauType,
- splitType -- pragmas
- )
-import CmdLineOpts
-import CostCentre
-import Id ( mkSysLocal, getIdUniType )
-import SrcLoc ( mkUnknownSrcLoc )
import StgSyn
-import SplitUniq
-import UniqSet ( emptyUniqSet
- IF_ATTACK_PRAGMAS(COMMA emptyUFM)
- )
-import Unique
-import Util
+
+import CmdLineOpts ( opt_AutoSccsOnIndividualCafs )
+import CostCentre -- lots of things
+import MkId ( mkSysLocal )
+import Id ( idType, emptyIdSet, Id )
+import SrcLoc ( noSrcLoc )
+import Type ( splitSigmaTy, splitFunTy_maybe )
+import UniqSupply ( getUnique, splitUniqSupply, UniqSupply )
+import Unique ( Unique )
+import Util ( removeDups, assertPanic, trace )
+import Outputable
infixr 9 `thenMM`, `thenMM_`
\end{code}
\begin{code}
-type CollectedCCs = ([CostCentre], -- locally defined ones
- [CostCentre]) -- ones needing "extern" decls
+type CollectedCCs = ([CostCentre], -- locally defined ones
+ [CostCentre]) -- ones needing "extern" decls
stgMassageForProfiling
- :: FAST_STRING -> FAST_STRING -- module name, group name
- -> SplitUniqSupply -- unique supply
- -> (GlobalSwitch -> Bool) -- command-line opts checker
- -> [PlainStgBinding] -- input
- -> (CollectedCCs, [PlainStgBinding])
+ :: FAST_STRING -> FAST_STRING -- module name, group name
+ -> UniqSupply -- unique supply
+ -> [StgBinding] -- input
+ -> (CollectedCCs, [StgBinding])
-stgMassageForProfiling mod_name grp_name us sw_chkr stg_binds
+stgMassageForProfiling mod_name grp_name us stg_binds
= let
((local_ccs, extern_ccs),
stg_binds2)
= initMM mod_name us (mapMM do_top_binding stg_binds)
fixed_ccs
- = if do_auto_sccs_on_cafs || doing_prelude
+ = if do_auto_sccs_on_cafs
then [] -- don't need "all CAFs" CC (for Prelude, we use PreludeCC)
else [all_cafs_cc]
in
((fixed_ccs ++ local_ccs_no_dups, extern_ccs_no_dups), stg_binds2)
where
- do_auto_sccs_on_cafs = sw_chkr AutoSccsOnIndividualCafs -- only use!
---UNUSED: do_auto_sccs_on_dicts = sw_chkr AutoSccsOnIndividualDicts -- only use! ** UNUSED really **
- doing_prelude = sw_chkr CompilingPrelude
+ do_auto_sccs_on_cafs = opt_AutoSccsOnIndividualCafs -- only use!
- all_cafs_cc = if doing_prelude
- then preludeCafsCostCentre
- else mkAllCafsCC mod_name grp_name
+ all_cafs_cc = mkAllCafsCC mod_name grp_name
----------
- do_top_binding :: PlainStgBinding -> MassageM PlainStgBinding
+ do_top_binding :: StgBinding -> MassageM StgBinding
do_top_binding (StgNonRec b rhs)
= do_top_rhs b rhs `thenMM` \ rhs' ->
returnMM (b, rhs2)
----------
- do_top_rhs :: Id -> PlainStgRhs -> MassageM PlainStgRhs
+ do_top_rhs :: Id -> StgRhs -> MassageM StgRhs
- do_top_rhs binder (StgRhsClosure rhs_cc bi fv u [] (StgSCC ty cc (StgConApp con args lvs)))
- -- top-level _scc_ around nothing but static data; toss it -- it's pointless
+ do_top_rhs binder (StgRhsClosure _ bi fv u [] (StgSCC ty cc (StgCon con args lvs)))
+ | not (isSccCountCostCentre cc)
+ -- Trivial _scc_ around nothing but static data
+ -- Eliminate _scc_ ... and turn into StgRhsCon
= returnMM (StgRhsCon dontCareCostCentre con args)
- do_top_rhs binder (StgRhsClosure rhs_cc bi fv u [] (StgSCC ty cc expr))
--- OLD:
--- | noCostCentreAttached rhs_cc || currentOrSubsumedCosts rhs_cc
--- -- doubtful guard... ToDo?
- -- Top level CAF with explicit scc expression. Attach CAF
- -- cost centre to StgRhsClosure and collect.
- = let
- calved_cc = cafifyCC cc
- in
- collectCC calved_cc `thenMM_`
- set_prevailing_cc calved_cc (
- do_expr expr
- ) `thenMM` \ expr' ->
- returnMM (StgRhsClosure calved_cc bi fv u [] expr')
-
- do_top_rhs binder (StgRhsClosure cc bi fv u [] body)
- | noCostCentreAttached cc || currentOrSubsumedCosts cc
- -- Top level CAF without a cost centre attached: Collect
- -- cost centre with binder name, if collecting CAFs.
+ do_top_rhs binder (StgRhsClosure no_cc bi fv u [] (StgSCC ty cc expr))
+ | (noCostCentreAttached no_cc || currentOrSubsumedCosts no_cc)
+ && not (isSccCountCostCentre cc)
+ -- Top level CAF without a cost centre attached
+ -- Attach and collect cc of trivial _scc_ in body
+ = collectCC cc `thenMM_`
+ set_prevailing_cc cc (do_expr expr) `thenMM` \ expr' ->
+ returnMM (StgRhsClosure cc bi fv u [] expr')
+
+ do_top_rhs binder (StgRhsClosure no_cc bi fv u [] body)
+ | noCostCentreAttached no_cc || currentOrSubsumedCosts no_cc
+ -- Top level CAF without a cost centre attached
+ -- Attach CAF cc (collect if individual CAF ccs)
= let
- (did_something, cc2)
+ (collect, caf_cc)
= if do_auto_sccs_on_cafs then
(True, mkAutoCC binder mod_name grp_name IsCafCC)
else
(False, all_cafs_cc)
in
- (if did_something
- then collectCC cc2
- else nopMM) `thenMM_`
- set_prevailing_cc cc2 (
- do_expr body
- ) `thenMM` \body2 ->
- returnMM (StgRhsClosure cc2 bi fv u [] body2)
-
- do_top_rhs binder (StgRhsClosure _ bi fv u args body@(StgSCC ty cc expr))
- -- We blindly use the cc off the _scc_
- = set_prevailing_cc cc (
- do_expr body
- ) `thenMM` \ body2 ->
- returnMM (StgRhsClosure cc bi fv u args body2)
+ (if collect then collectCC caf_cc else nopMM) `thenMM_`
+ set_prevailing_cc caf_cc (do_expr body) `thenMM` \ body' ->
+ returnMM (StgRhsClosure caf_cc bi fv u [] body')
+
+ do_top_rhs binder (StgRhsClosure cc bi fv u [] body)
+ -- Top level CAF with cost centre attached
+ -- Should this be a CAF cc ??? Does this ever occur ???
+ = trace ("SCCfinal: CAF with cc: " ++ showCostCentre False cc) $
+ collectCC cc `thenMM_`
+ set_prevailing_cc cc (do_expr body) `thenMM` \ body' ->
+ returnMM (StgRhsClosure cc bi fv u [] body')
+
+ do_top_rhs binder (StgRhsClosure _ bi fv u args (StgSCC ty cc expr))
+ | not (isSccCountCostCentre cc)
+ -- Top level function with trivial _scc_ in body
+ -- Attach and collect cc of trivial _scc_
+ = collectCC cc `thenMM_`
+ set_prevailing_cc cc (do_expr expr) `thenMM` \ expr' ->
+ returnMM (StgRhsClosure cc bi fv u args expr')
do_top_rhs binder (StgRhsClosure cc bi fv u args body)
+ -- Top level function, probably subsumed
= let
- cc2 = if noCostCentreAttached cc
- then subsumedCosts -- it's not a thunk; it is top-level & arity > 0
- else cc
+ (cc_closure, cc_body)
+ = if noCostCentreAttached cc
+ then (subsumedCosts, useCurrentCostCentre)
+ else (cc, cc)
in
- set_prevailing_cc cc2 (
- do_expr body
- ) `thenMM` \ body' ->
- returnMM (StgRhsClosure cc2 bi fv u args body')
+ set_prevailing_cc cc_body (do_expr body) `thenMM` \ body' ->
+ returnMM (StgRhsClosure cc_closure bi fv u args body')
do_top_rhs binder (StgRhsCon cc con args)
- = returnMM (StgRhsCon dontCareCostCentre con args)
-- Top-level (static) data is not counted in heap
-- profiles; nor do we set CCC from it; so we
-- just slam in dontCareCostCentre
+ = returnMM (StgRhsCon dontCareCostCentre con args)
------
- do_expr :: PlainStgExpr -> MassageM PlainStgExpr
+ do_expr :: StgExpr -> MassageM StgExpr
do_expr (StgApp fn args lvs)
= boxHigherOrderArgs (StgApp fn) args lvs
- do_expr (StgConApp con args lvs)
- = boxHigherOrderArgs (StgConApp con) args lvs
+ do_expr (StgCon con args lvs)
+ = boxHigherOrderArgs (StgCon con) args lvs
- do_expr (StgPrimApp op args lvs)
- = boxHigherOrderArgs (StgPrimApp op) args lvs
+ do_expr (StgPrim op args lvs)
+ = boxHigherOrderArgs (StgPrim op) args lvs
do_expr (StgSCC ty cc expr) -- Ha, we found a cost centre!
- = collectCC cc `thenMM_`
- set_prevailing_cc cc (
- do_expr expr
- ) `thenMM` \ expr' ->
+ = collectCC cc `thenMM_`
+ set_prevailing_cc cc (do_expr expr) `thenMM` \ expr' ->
returnMM (StgSCC ty cc expr')
do_expr (StgCase expr fv1 fv2 uniq alts)
returnMM (StgBindDefault b is_used e')
do_expr (StgLet b e)
- = set_prevailing_cc_maybe useCurrentCostCentre (
- do_binding b `thenMM` \ b' ->
- do_expr e `thenMM` \ e' ->
- returnMM (StgLet b' e') )
+ = do_binding b `thenMM` \ b' ->
+ do_expr e `thenMM` \ e' ->
+ returnMM (StgLet b' e')
do_expr (StgLetNoEscape lvs1 lvs2 rhs body)
- = set_prevailing_cc_maybe useCurrentCostCentre (
- do_binding rhs `thenMM` \ rhs' ->
- do_expr body `thenMM` \ body' ->
- returnMM (StgLetNoEscape lvs1 lvs2 rhs' body') )
+ = do_binding rhs `thenMM` \ rhs' ->
+ do_expr body `thenMM` \ body' ->
+ returnMM (StgLetNoEscape lvs1 lvs2 rhs' body')
----------
- do_binding :: PlainStgBinding -> MassageM PlainStgBinding
+ do_binding :: StgBinding -> MassageM StgBinding
do_binding (StgNonRec b rhs)
= do_rhs rhs `thenMM` \ rhs' ->
= do_rhs rhs `thenMM` \ rhs' ->
returnMM (b, rhs')
- do_rhs :: PlainStgRhs -> MassageM PlainStgRhs
+ 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 cafifying, etc.
- -- (ToDo: consolidate??)
+ -- but we don't have to worry about cafs etc.
-{- Patrick says NO: it will mess up our counts (WDP 95/07)
- do_rhs (StgRhsClosure _ bi fv u [] (StgSCC _ cc (StgConApp con args lvs)))
+ do_rhs (StgRhsClosure _ bi fv u [] (StgSCC ty cc (StgCon con args lvs)))
+ | not (isSccCountCostCentre cc)
= collectCC cc `thenMM_`
returnMM (StgRhsCon cc con args)
--}
- do_rhs (StgRhsClosure _ bi fv u args body@(StgSCC _ cc _))
- = set_prevailing_cc cc (
- do_expr body
- ) `thenMM` \ body' ->
- returnMM (StgRhsClosure cc bi fv u args body')
+ do_rhs (StgRhsClosure _ bi fv u args (StgSCC ty cc expr))
+ | not (isSccCountCostCentre cc)
+ = collectCC cc `thenMM_`
+ set_prevailing_cc cc (do_expr expr) `thenMM` \ expr' ->
+ returnMM (StgRhsClosure cc bi fv u args expr')
do_rhs (StgRhsClosure cc bi fv u args body)
- = use_prevailing_cc_maybe cc `thenMM` \ cc2 ->
- set_prevailing_cc cc2 (
- do_expr body
- ) `thenMM` \ body' ->
- returnMM (StgRhsClosure cc2 bi fv u args body')
+ = set_prevailing_cc_maybe cc $ \ cc' ->
+ set_lambda_cc (do_expr body) `thenMM` \ body' ->
+ returnMM (StgRhsClosure cc' bi fv u args body')
do_rhs (StgRhsCon cc con args)
- = use_prevailing_cc_maybe cc `thenMM` \ cc2 ->
- returnMM (StgRhsCon cc2 con args)
- -- ToDo: Box args (if lex) Pass back let binding???
- -- Nope: maybe later? WDP 94/06
+ = 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
\end{code}
%************************************************************************
\begin{code}
boxHigherOrderArgs
- :: ([PlainStgAtom] -> PlainStgLiveVars -> PlainStgExpr)
- -- An application lacking its arguments and live-var info
- -> [PlainStgAtom] -- arguments which we might box
- -> PlainStgLiveVars -- live var info, which we do *not* try
+ :: ([StgArg] -> StgLiveVars -> StgExpr)
+ -- An application lacking its arguments and live-var info
+ -> [StgArg] -- arguments which we might box
+ -> StgLiveVars -- live var info, which we do *not* try
-- to maintain/update (setStgVarInfo will
-- do that)
- -> MassageM PlainStgExpr
+ -> MassageM StgExpr
+
+boxHigherOrderArgs almost_expr args live_vars
+ = returnMM (almost_expr args live_vars)
+
+{- No boxing for now ... should be moved to desugarer and preserved ...
boxHigherOrderArgs almost_expr args live_vars
- = mapAccumMM do_arg [] args `thenMM` \ (let_bindings, new_args) ->
- get_prevailing_cc `thenMM` \ cc ->
- returnMM (foldr (mk_stg_let cc) (almost_expr new_args live_vars) let_bindings)
+ = 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)
where
---------------
do_arg bindings atom@(StgLitAtom _) = returnMM (bindings, atom)
= let
var_type = getIdUniType old_var
in
- if not (is_fun_type var_type) then
- returnMM (bindings, atom) -- easy
- else
- -- make a trivial let-binding for the higher-order guy
+ if toplevelishId old_var && isFunType (getTauType var_type)
+ then
+ -- make a trivial let-binding for the top-level function
getUniqueMM `thenMM` \ uniq ->
let
- new_var = mkSysLocal SLIT("ho") uniq var_type mkUnknownSrcLoc
+ new_var = mkSysLocal SLIT("ho") uniq var_type noSrcLoc
in
returnMM ( (new_var, old_var) : bindings, StgVarAtom new_var )
- where
- is_fun_type ty = isFunType (getTauType ty)
+ else
+ returnMM (bindings, atom)
---------------
- mk_stg_let :: CostCentre -> (Id, Id) -> PlainStgExpr -> PlainStgExpr
+ mk_stg_let :: CostCentre -> (Id, Id) -> StgExpr -> StgExpr
mk_stg_let cc (new_var, old_var) body
= let
- rhs_body = StgApp (StgVarAtom old_var) [{-no args-}] bOGUS_LVs
-
- rhs = StgRhsClosure cc
- stgArgOcc -- safe...
- [{-junk-}] Updatable [{-no args-}] rhs_body
+ rhs_body = StgApp (StgVarAtom old_var) [{-args-}] bOGUS_LVs
+ rhs_closure = StgRhsClosure cc stgArgOcc [{-fvs-}] ReEntrant [{-args-}] rhs_body
in
- StgLet (StgNonRec new_var rhs) body
+ StgLet (StgNonRec new_var rhs_closure) body
where
bOGUS_LVs = emptyUniqSet -- easier to print than: panic "mk_stg_let: LVs"
+-}
\end{code}
%************************************************************************
-> CostCentre -- prevailing CostCentre
-- if none, subsumedCosts at top-level
-- useCurrentCostCentre at nested levels
- -> SplitUniqSupply
+ -> UniqSupply
-> CollectedCCs
-> (CollectedCCs, result)
-- the initUs function also returns the final UniqueSupply and CollectedCCs
initMM :: FAST_STRING -- module name, which we may consult
- -> SplitUniqSupply
+ -> UniqSupply
-> MassageM a
-> (CollectedCCs, a)
-initMM mod_name init_us m = m mod_name subsumedCosts{-top-level-} init_us ([],[])
+initMM mod_name init_us m = m mod_name noCostCentre init_us ([],[])
thenMM :: MassageM a -> (a -> MassageM b) -> MassageM b
thenMM_ :: MassageM a -> (MassageM b) -> MassageM b
returnMM (b3, r:rs)
getUniqueMM :: MassageM Unique
-getUniqueMM mod scope_cc us ccs = (ccs, getSUnique us)
+getUniqueMM mod scope_cc us ccs = (ccs, getUnique us)
\end{code}
\begin{code}
-set_prevailing_cc, set_prevailing_cc_maybe
- :: CostCentre -> MassageM a -> MassageM a
-
+set_prevailing_cc :: CostCentre -> 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
- -- set unconditionally
-set_prevailing_cc_maybe cc_to_set_to action mod scope_cc us ccs
+set_prevailing_cc_maybe :: CostCentre -> (CostCentre -> 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
- -- used when switching from top-level to nested
- -- scope; if we were chugging along as "subsumed",
- -- we change to the new thing; otherwise we
- -- keep what we had.
+ cc_to_use
+ = if noCostCentreAttached cc_to_try || currentOrSubsumedCosts 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
+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
- = if (costsAreSubsumed scope_cc)
- then cc_to_set_to
- else scope_cc -- carry on as before
+ = if isCafCC scope_cc || isDictCC scope_cc
+ then useCurrentCostCentre
+ else scope_cc
in
action mod cc_to_use us ccs
+
get_prevailing_cc :: MassageM CostCentre
get_prevailing_cc mod scope_cc us ccs = (ccs, scope_cc)
-use_prevailing_cc_maybe :: CostCentre -> MassageM CostCentre
-
-use_prevailing_cc_maybe cc_to_try mod scope_cc us ccs
- = let
- cc_to_use
- = if not (noCostCentreAttached cc_to_try
- || currentOrSubsumedCosts cc_to_try) then
- cc_to_try
- else
- uncalved_scope_cc
- -- carry on as before, but be sure it
- -- isn't marked as CAFish (we're
- -- crossing a lambda...)
- in
- (ccs, cc_to_use)
- where
- uncalved_scope_cc = unCafifyCC scope_cc
\end{code}
\begin{code}
projects / ghc-hetmet.git / blobdiff