hughperkins:
[snip] unsafeWrite[snip] [snip]unsafeRead[snip] Hi Donald, the idea is to use this for operational code, so avoiding unsafe operations is preferable ;-) You'll note
On 7/15/07, Donald Bruce Stewart <[1]dons@cse.unsw.edu.au> wrote: that the C# version is not using unsafe operations, although to be fair that's because they worked out slower than the safe version ;-)
"unsafe"' here just means direct array indexing. Same as the other languages. Haskell's 'unsafe' is a little more paranoid that other languages.
Also, the whole algorithm is bound to the IO Monad, which is something I'd like to avoid if possible, since my entire interest in Haskell stems from the possibilites of running programs easily on 1 megacore processors in the future.
You're deciding that on a cache-thrashing primes benchmark? Since the goal is to flip bits very quickly in the cache, you could localise this to the ST monad then, as its perfectly pure on the outside.
Anyway, congrats you got nearly as fast as C#!
Try the other version I just sent. This one trashes cache lines needlessly. What C# version are you using, by the way? (So I can check if it does any tricks). -- Don