rusi <rustompm...@gmail.com> writes: > On an 8086/8088 a MUL (multiply) instruction was of the order of 100 > clocks ... On most modern processors (after the pentium) the > difference has mostly vanished. I cant find a good data sheet to > quote though
See http://www.agner.org/optimize/ : 4. Instruction tables: Lists of instruction latencies, throughputs and micro-operation breakdowns for Intel, AMD and VIA CPUs Multiplication is now fast but DIV is still generally much slower. There are ways to make fast parallel dividers that I think nobody bothers with, because of chip area and because one can often optimize division out of algorithms, replacing most of it with multiplication. Worrying about this sort of micro-optimization in CPython is almost always misplaced, since the interpreter overhead generally swamps any slowness of the machine arithmetic. -- http://mail.python.org/mailman/listinfo/python-list
