On Mon, 4 Aug 2008, Dag Sverre Seljebotn wrote: > Stefan Behnel wrote: >> Dag Sverre Seljebotn wrote: >>> If we make positive int literals unsigned long rather than plain long, >>> constant-index buffer lookups are going to be optimized for free. Is >>> there going to be any ill side-effects from doing this? >>> >>> (If not, I can always special-case int literals used for buffer lookups.) >> >> What about enabling this, adding a test module dedicated to integer >> literals, casting and arithmetic, and running the (complete) test suite >> with >> >> -Wall -pedantic >> >> ? > > Sure, but that would have been a lot of work only to get a reply here > afterwards that "this whole idea would obviously not work because X" > from people who know the code base better :-)
I think in general that is a good idea, but the problem is that PyLong_FromUnsignedLong is slower than PyInt_FromLong and produces python longs rather than python ints. One would need a special type (or flag) to indicate that the top bit can be assumed to be 0. - Robert _______________________________________________ Cython-dev mailing list [email protected] http://codespeak.net/mailman/listinfo/cython-dev
