[Haskell-cafe] A tale of three shootout entries

[Richard Kelsall]

Don Stewart wrote:
...
> 
> There may well have been changes to the strictness analyser that make
> some of the bangs (or most) unnecessary now. Also, its very likely 
> I didn't check all combinations of strict and lazy arguments for the
> optimal evaluation strategy :)

I suspect the optimum details will change again when we get to GHC 6.8.
Yes, I got bored trying different combinations too. A genetic algorithm
that knocks out different combinations might be fun. The ones in rand
seem to make the most difference and I decided the code was easier to
read if I took them all out.

> If it seems to be running consitently faster (and producing better Core
> code), by all means submit. I don't think this is a ghc bug or anything
> like that though: just overuse of bangs, leading to unnecessary work.
> 
> -- Don
> 

It was consistently faster on my machine, but it would be interesting
to compare with the run-times on Sterling's PPC machine. I'll have a
play with Sterling's new program and report.


Richard.