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+{-# OPTIONS_GHC -O2 -ddump-simpl  #-}
+module Roman where
+
+{- From: Roman Leshchinskiy [mailto:rl@cse.unsw.edu.au] 
+   Sent: 07 February 2008 03:34
+   Subject: Quadratic SpecConstr 
+
+Here is a program which makes SpecConstr generate a quadratic number of
+iterations:
+-}
+
+
+bar :: Int -> Int -> Int
+bar m n = foo n (n,n) (n,n) (n,n) (n,n)
+   where
+     foo :: Int -> (Int,Int) -> (Int,Int) -> (Int,Int) -> (Int,Int) -> Int
+     foo n p q r s
+       | n == 0    = m
+       | n > 3000  = case p of { (p1,p2) -> foo (n-1) (p2,p1) q r s }
+       | n > 2000  = case q of { (q1,q2) -> foo (n-1) p (q2,q1) r s }
+       | n > 1000  = case r of { (r1,r2) -> foo (n-1) p q (r2,r1) s }
+       | otherwise = case s of { (s1,s2) -> foo (n-1) p q r (s2,s1) }
+
+{- For this particular function, I get 14 specialisations, one for each
+   possible combination of arguments.
+ 
+   However, since we can see all the call sites outside the loop, we could
+   use that to 'seed' the specialisation, and get just one specialisation.
+-}
+
+
+-- Eyeball guidance: 
+-- 	There should be just one specialisation for foo
+-- 	Indeed, the original function should disappear,
+--		since it isn't used
+