GHC-6.4.1 much slower than GHC-6.4

[Christian Maeder]

Mirko Rahn wrote:
> 
>> I've found a way to speed up your code for ghc-6.4.1.
>> Replace the "where" with a "case" in PCP.Suc.suc_rules (see below)
> 
> Okay, thanks, that works fine.

Yes, It's even quite fast without optimization (I did not check with 
ghc-6.4, though)

>> (Maybe that is a good idea in PCP.Rules.Suc, too)
> 
> Seems to be unimportant whether the replacement is done in PCP.Rules.Suc 

Yes, it is unimportant.

Christian