Mark Dickinson <dicki...@gmail.com> added the comment: Here's a version of the patch that includes optimizations to basecase multiplication, and a streamlined x_divrem for faster division. With Victor's benchmark, I'm getting 43% speed increase on 64-bit Linux/Core 2 Duo.
Note: the base patch is stable and ready for review; in contrast, the optimizations are still in a state of flux, so the +optimizations patch is just there as an example of what might be possible. About using uint64_t: the 64-bit type isn't really used very much: its main role is as the result type of a 32-bit by 32-bit multiplication. So it might not matter too much if it's an emulated type; what's important is that the 32-bit by 32-bit multiply with 64-bit results is done in a single CPU instruction. I don't know how to test for this. Do you know of a mainstream system where this isn't true? I'll test this tonight on 32-bit PPC and 32=bit Intel, and report back. I don't care very much about trying to *automatically* do the right thing for small or embedded systems: they can use the --disable-big-digits configure option to turn 30-bit digits off. Antoine, do you think we should be using 30-bit digits by default *only* on 64-bit machines? I guess I could go with that, if it can be manually overridden by the configure option. Added file: http://bugs.python.org/file13118/30bit_longdigit13+optimizations.patch _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue4258> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
