Int vs Integer benchmark

[S.D.Mechveliani]

Here is some simple benchmark for  Int vs Integer  performance.

In the system i use, it gives the time ratio Integer/Int 
(for the whole task)  = 4.5.

The difference is obtained only by switching  Z = Integer, Int.


------------------
Sergey Mechveliani
[EMAIL PROTECTED]




------------------------------------------------------------------
type Z = Integer  --Int

main =  -- compute extended gcd for many x,y and sum the results
        let  
          (d,n,m) = (40,5000,10000) :: (Z,Z,Z)
          ns      = [n..(n+d)]
          ms      = [m..(m+d)]
          pairs   = [(x,y)| x<-ns, y<-ms]

          tripls = map (\ (x,y)->(x,y,gcdE x y))  pairs 

          s      = sum  (map (\ (_,_,(d,u,v))->d+u-v) tripls)

          --boo = all test tripls    --this tests gcdE
        in
        putStr (shows s "\n")



-- gcdE x y -> (d,u,v):   d = gcd(x,y) = u*x + v*y

gcdE :: Integral a => a -> a -> (a,a,a)

gcdE 0 y =  (y,0,1)
gcdE x y =  g (1,0,x) (0,1,y)
  where
  g (u1,u2,u3) (v1,v2,v3) =  
                   if  v3==0  then  (u3,u1,u2)
                   else
                     case  quotRem u3 v3  
                     of
                       (q,r) -> g (v1,v2,v3) (u1-q*v1, u2-q*v2, r)


test (x,y,(d,u,v)) =  d==(u*x+v*y)  &&  d==(gcd x y)