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diff --git a/compiler/simplStg/SimplStg.lhs b/compiler/simplStg/SimplStg.lhs
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+%
+% (c) The GRASP/AQUA Project, Glasgow University, 1993-1998
+%
+\section[SimplStg]{Driver for simplifying @STG@ programs}
+
+\begin{code}
+module SimplStg ( stg2stg ) where
+
+#include "HsVersions.h"
+
+import StgSyn
+
+import CostCentre       ( CollectedCCs )
+import SCCfinal		( stgMassageForProfiling )
+import StgLint		( lintStgBindings )
+import StgStats	        ( showStgStats )
+import SRT		( computeSRTs )
+
+import Packages		( HomeModules )
+import DynFlags		( DynFlags(..), DynFlag(..), dopt, StgToDo(..),
+			  getStgToDo )
+import Id		( Id )
+import Module		( Module )
+import ErrUtils		( doIfSet_dyn, dumpIfSet_dyn, showPass )
+import UniqSupply	( mkSplitUniqSupply, splitUniqSupply )
+import Outputable
+\end{code}
+
+\begin{code}
+stg2stg :: DynFlags		     -- includes spec of what stg-to-stg passes to do
+	-> HomeModules
+	-> Module		     -- module name (profiling only)
+	-> [StgBinding]		     -- input...
+	-> IO ( [(StgBinding,[(Id,[Id])])]  -- output program...
+	      , CollectedCCs)        -- cost centre information (declared and used)
+
+stg2stg dflags pkg_deps module_name binds
+  = do	{ showPass dflags "Stg2Stg"
+	; us <- mkSplitUniqSupply 'g'
+
+	; doIfSet_dyn dflags Opt_D_verbose_stg2stg 
+		      (printDump (text "VERBOSE STG-TO-STG:"))
+
+	; (binds', us', ccs) <- end_pass us "Stg2Stg" ([],[],[]) binds
+
+		-- Do the main business!
+	; (processed_binds, _, cost_centres) 
+		<- foldl_mn do_stg_pass (binds', us', ccs) (getStgToDo dflags)
+
+	; let srt_binds = computeSRTs processed_binds
+
+	; dumpIfSet_dyn dflags Opt_D_dump_stg "STG syntax:" 
+	     		(pprStgBindingsWithSRTs srt_binds)
+
+	; return (srt_binds, cost_centres)
+   }
+
+  where
+    stg_linter = if dopt Opt_DoStgLinting dflags
+		 then lintStgBindings
+		 else ( \ whodunnit binds -> binds )
+
+    -------------------------------------------
+    do_stg_pass (binds, us, ccs) to_do
+      =	let
+	    (us1, us2) = splitUniqSupply us
+	in
+	case to_do of
+	  D_stg_stats ->
+	     trace (showStgStats binds)
+	     end_pass us2 "StgStats" ccs binds
+
+	  StgDoMassageForProfiling ->
+	     {-# SCC "ProfMassage" #-}
+	     let
+		 (collected_CCs, binds3)
+		   = stgMassageForProfiling pkg_deps module_name us1 binds
+	     in
+	     end_pass us2 "ProfMassage" collected_CCs binds3
+
+    end_pass us2 what ccs binds2
+      = do -- report verbosely, if required
+	   dumpIfSet_dyn dflags Opt_D_verbose_stg2stg what
+	      (vcat (map ppr binds2))
+	   let linted_binds = stg_linter what binds2
+	   return (linted_binds, us2, ccs)
+	    -- return: processed binds
+	    -- 	       UniqueSupply for the next guy to use
+	    --	       cost-centres to be declared/registered (specialised)
+	    --	       add to description of what's happened (reverse order)
+
+-- here so it can be inlined...
+foldl_mn f z []     = return z
+foldl_mn f z (x:xs) = f z x	>>= \ zz ->
+		     foldl_mn f zz xs
+\end{code}