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digitalmars.D - Re: Biggest problems w/ D - 64bit

renoX Wrote:
 2x?
 Your code must do a lot of 64b computation!

Yes. Lots of 64-bit integer shifts of pointer values. The only other difference is that 32-bit pointer addresses are closer together. The result: The exact same code compiled for 32- or 64-bit has a 2x speed difference.
 
 When the AMD64 was released benchmarks made showed at best a 20% 
 improvement, which is quite a lot to get with a simple recompilation 
 assuming the code is 64b clean of course but is nowhere 2x.

Yes. 20% is a good rule of thumb. That's what we usually see, for general object-oriented programming. System-level programming is different. I'll try gdc someday....
Aug 10 2007