ghc and signal processing

[Mike Gunter]

Hmmm.  With -O2 on GHC 6.2, I get 0.177s, 0.217s, and 0.348s for your
three Haskell examples and 0.187s (with gcc -O2) for your C example.
The output of -ddump-simpl for the looks perfect for the second
Haskell example.  My GHC seems to be doing a bang-up job here.  What's
wrong with yours?  (For the third example GHC's code could be improved
by additional inlining or hoisting of a constant array outside of the
loop.)

	mike