[Haskell-cafe] Re: speed: ghc vs gcc

On a G4: s.hs (which does not need bang patterns) is:

main = seq (sum0 (10^9) 0) (return ())

sum0 :: Int -> Int -> Int sum0 0 acc = acc sum0 x acc = sum0 (x-1) $! (acc+x)

And s.c is (actually including 10^9, which Bulat's did not):

main() { int sum=0; for(int i=1000*1000*1000; i>0; i--) sum += i; }

I compiled them with ghc --make -O2 s.hs -o shs gcc -o sc -std=c99 -O3 -funroll-loops s.c And timed them: $ time ./shs real 0m3.309s user 0m3.008s sys 0m0.026s $ time ./sc real 0m0.411s user 0m0.316s sys 0m0.006s So C is 9.4 times faster. And via-C did not help: $ ghc -fvia-C -optc "-O3 -funroll-loops" --make -O2 s.hs -o shs-via-C $ time ./shs-via-C real 0m7.051s user 0m3.010s sys 0m0.050s -- Chris