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diff --git a/compiler/nativeGen/NCGMonad.hs b/compiler/nativeGen/NCGMonad.hs
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+++ b/compiler/nativeGen/NCGMonad.hs
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+-- -----------------------------------------------------------------------------
+--
+-- (c) The University of Glasgow 1993-2004
+-- 
+-- The native code generator's monad.
+--
+-- -----------------------------------------------------------------------------
+
+module NCGMonad (
+	NatM_State(..), mkNatM_State,
+
+	NatM, -- instance Monad
+	initNat, addImportNat, getUniqueNat,
+	mapAccumLNat, setDeltaNat, getDeltaNat,
+	getBlockIdNat, getNewLabelNat, getNewRegNat, getNewRegPairNat,
+	getPicBaseMaybeNat, getPicBaseNat
+ ) where
+  
+#include "HsVersions.h"
+
+import Cmm		( BlockId(..) )
+import CLabel		( CLabel, mkAsmTempLabel )
+import MachRegs
+import MachOp		( MachRep )
+import UniqSupply
+import Unique		( Unique )
+
+
+data NatM_State = NatM_State {
+			natm_us      :: UniqSupply,
+			natm_delta   :: Int,
+			natm_imports :: [(CLabel)],
+			natm_pic     :: Maybe Reg
+		}
+
+newtype NatM result = NatM (NatM_State -> (result, NatM_State))
+
+unNat (NatM a) = a
+
+mkNatM_State :: UniqSupply -> Int -> NatM_State
+mkNatM_State us delta = NatM_State us delta [] Nothing
+
+initNat :: NatM_State -> NatM a -> (a, NatM_State)
+initNat init_st m = case unNat m init_st of { (r,st) -> (r,st) }
+
+instance Monad NatM where
+  (>>=) = thenNat
+  return = returnNat
+
+thenNat :: NatM a -> (a -> NatM b) -> NatM b
+thenNat expr cont
+  = NatM $ \st -> case unNat expr st of
+			(result, st') -> unNat (cont result) st'
+
+returnNat :: a -> NatM a
+returnNat result = NatM $ \st ->  (result, st)
+
+mapAccumLNat :: (acc -> x -> NatM (acc, y))
+                -> acc
+	        -> [x]
+	        -> NatM (acc, [y])
+
+mapAccumLNat f b []
+  = return (b, [])
+mapAccumLNat f b (x:xs)
+  = do (b__2, x__2)  <- f b x
+       (b__3, xs__2) <- mapAccumLNat f b__2 xs
+       return (b__3, x__2:xs__2)
+
+getUniqueNat :: NatM Unique
+getUniqueNat = NatM $ \ (NatM_State us delta imports pic) ->
+    case splitUniqSupply us of
+         (us1,us2) -> (uniqFromSupply us1, (NatM_State us2 delta imports pic))
+
+getDeltaNat :: NatM Int
+getDeltaNat = NatM $ \ st -> (natm_delta st, st)
+
+setDeltaNat :: Int -> NatM ()
+setDeltaNat delta = NatM $ \ (NatM_State us _ imports pic) ->
+   ((), NatM_State us delta imports pic)
+
+addImportNat :: CLabel -> NatM ()
+addImportNat imp = NatM $ \ (NatM_State us delta imports pic) -> 
+   ((), NatM_State us delta (imp:imports) pic)
+
+getBlockIdNat :: NatM BlockId
+getBlockIdNat = do u <- getUniqueNat; return (BlockId u)
+
+getNewLabelNat :: NatM CLabel
+getNewLabelNat = do u <- getUniqueNat; return (mkAsmTempLabel u)
+
+getNewRegNat :: MachRep -> NatM Reg
+getNewRegNat rep = do u <- getUniqueNat; return (mkVReg u rep)
+
+getNewRegPairNat :: MachRep -> NatM (Reg,Reg)
+getNewRegPairNat rep = do 
+  u <- getUniqueNat
+  let lo = mkVReg u rep; hi = getHiVRegFromLo lo
+  return (lo,hi)
+
+getPicBaseMaybeNat :: NatM (Maybe Reg)
+getPicBaseMaybeNat = NatM (\state -> (natm_pic state, state))
+
+getPicBaseNat :: MachRep -> NatM Reg
+getPicBaseNat rep = do
+  mbPicBase <- getPicBaseMaybeNat
+  case mbPicBase of
+        Just picBase -> return picBase
+        Nothing -> do
+            reg <- getNewRegNat rep
+            NatM (\state -> (reg, state { natm_pic = Just reg }))