Re[2]: [Haskell-cafe] Re: speed: ghc vs gcc

Hello Peter, Friday, February 20, 2009, 6:34:04 PM, you wrote:

Well C# does it with a for loop in 2300ms, and when using a IEnumerable sequence it needs 19936ms. Very much like the Haskell code. But of course the Haskell code could optimize the sum I guess, I assume it is using the lazy version of sum by default.

the question is what is the natural for every language

Anyway it was more of a question. Does GHC perform register allocation (e.g. using graph colouring)  and loop unrolling?

afaik, ghc can be compared with 20-years old C compilers. it uses registers for performing tight loops but has very simple register allocation procedure. also it doesn't unroll loops

On Fri, Feb 20, 2009 at 4:22 PM, Colin Paul Adams wrote:

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"Peter" == Peter Verswyvelen writes:

   Peter> So GHC is about 3 to 4 times slower as Visual C++ / GCC    Peter> without loop unrolling, which is not too bad since GHC does    Peter> not perform register optimization and loop unrolling yet    Peter> no?

I would call it rather poor.

And I don't accept a since of that form as valid mitigation. -- Colin Adams Preston Lancashire

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