[Haskell-cafe] C-like Haskell

[Jake McArthur]

Ross Mellgren wrote:
> Duncan, I think you must have some magics -- on my machine the original 
> code also takes forever.
> Running with +RTS -S indicates it's allocating several gig of memory or 
> more.
> 
> Applying some bang patterns gives me ~8s for 10^8 and somewhat more than 
> a minute for 10^9

It works great for me. 64 bit, GHC 6.10.1, no bang patterns or other 
magic. Works about the same with both Int and Int64.

% time ./ctest
3141592649589764829

real	0m2.614s
user	0m2.610s
sys	0m0.003s

% time ./hstest
3141592653589764829

real	0m3.878s
user	0m3.870s
sys	0m0.003s

% ./hstest +RTS -S
./hstest +RTS -S
     Alloc    Copied     Live    GC    GC     TOT     TOT  Page Flts
     bytes     bytes     bytes  user  elap    user    elap
3141592653589764829
      8512       688     17136  0.00  0.00    3.94    3.94    0    0 
(Gen:  1)
         0                      0.00  0.00

            8,512 bytes allocated in the heap
              688 bytes copied during GC
           17,136 bytes maximum residency (1 sample(s))
           19,728 bytes maximum slop
                1 MB total memory in use (0 MB lost due to fragmentation)

   Generation 0:     0 collections,     0 parallel,  0.00s,  0.00s elapsed
   Generation 1:     1 collections,     0 parallel,  0.00s,  0.00s elapsed

   INIT  time    0.00s  (  0.00s elapsed)
   MUT   time    3.94s  (  3.94s elapsed)
   GC    time    0.00s  (  0.00s elapsed)
   EXIT  time    0.00s  (  0.00s elapsed)
   Total time    3.94s  (  3.94s elapsed)

   %GC time       0.0%  (0.0% elapsed)

   Alloc rate    2,158 bytes per MUT second

   Productivity  99.9% of total user, 100.0% of total elapsed