Delphi – Importing D7 DPR in Delphi 2009: “Invalid character in text content”

There's some info in this podcast. What we know now: Yes, there will probably be one. But it probably won't be as feature-rich as the last Turbo was.

ASM output is not a good indication of algorithm speed. Also, from what I can see, the two pieces of code are doing almost the identical work. The biggest difference seem to be the memory access strategy and the first is using roll-left instead of the equivalent set of instructions (shl | shr -- most higher-level programming languages leave out the "roll" operators). The latter may pipeline better than the former.

ASM optimization is black magic and sometimes more instructions execute faster than fewer.

To be sure, benchmark both and pick the winner. If you like the output of the second but the first is faster, plug the second's values into the first.

rol edx,5 { edx := (edx shl 5) or (edx shr 27)... }

Note that different machines will run the code in different ways, so if speed is REALLY of the essence then benchmark it on the hardware that you plan to run the final application on. I'm willing to bet that over megabytes of data the difference will be a matter of milliseconds -- which is far less than the operating system is taking away from you.

PS. I'm not convinced this algorithm creates even distribution, something you explicitly called out (have you run the histograms?). You may look at porting this hash function to Delphi. It may not be as fast as the above algorithm but it appears to be quite fast and also gives good distribution. Again, we're probably talking on the order of milliseconds of difference over megabytes of data.