[curiousDog]

Do all 64-bit programs tend to be slower all the time though? I'd think it would be faster because you're processing more data per clock cycle. Or is that the x64 JIT hasn't been optimized to take advantage of the latest gen of 64-bit processors (I heard stuff about not making use of the latest Math.Pow a while ago)?

[freikev]

Programs that are pointer-heavy tend to be a little slower. There's really not that much 64-bit arithmetic going on in the average application, so the more data per clock cycle only helps in a particular class of apps. Cryptography tends to do significantly better, for that exact reason. You do seem to be conflating code quality with compiler throughput, though. I'll try to clarify in much more detail in a CLR Codegen blog post soon.

[groovy2shoes]

> I'd think it would be faster because you're processing more data per clock cycle.

This is only true if you happen to be dealing with integers larger than 32 bits (rarely in most of today's code). The real performance benefit of x64 has more to do with a larger number of general-purpose registers. More registers allow (but don't guarantee) programs to spend less time accessing main memory, thus gaining some speed.

[curiousDog]

Yes, I knew about the registers. I guess I overestimated the number of applications that involve large number computations.

[groovy2shoes]

Or perhaps I underestimated them...