Mark Dickinson <dicki...@gmail.com> added the comment: > Daniel Stutzbach <dan...@stutzbachenterprises.com> added the comment: > > Speaking of getting side-tracked, I didn't see an answer to a question I > asked earlier. I'd like to get some feedback before I proceed with revising > the patch. > > For the find-last-set-bit (to replace log2) and count-set-bits operations, > would it be worthwhile to create a pybits.h and .c that defines > _Py_FindLastSetBit and _Py_CountSetBits? (with appropriate logic in the .h > and configure.in to use system/compiler versions if available)
How about putting them in pymath.c and pymath.h? Then there's no need for new files. There's the possible issue that the two bit-counting methods operate on different types, though. > There are already two implementations of find-last-set-bit in Python: > bits_in_digit() in Objects/longobject.c and hi0bits() in Python/dtoa.c, which > I could consolidate. dtoa.c should be left alone, ideally: it's currently almost completely self-contained, and also very close to the original dtoa.c from David Gay, which makes it easy to incorporate fixes from upstream. So it's just Objects/longobject.c that would share the code. > Alternately, I could just add static functions to mathmodule.c with the > simplest possible implementation (they're only called once per factorial, so > the performance impact is minimal). That would work, too. ---------- _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue8692> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
