David, all Very interesting statistics! As I suspected, Glen's routine is indeed faster on a real machine even though it executed more instructions. I'll be very interested to see how the real z196 instruction times compares to these different routines.
I'll leave Fritz as #1 running on z390 but add note with your results showing Glen's routine does run faster on a real machine. This is a good example of how pipelining and register versus main memory instructions really do matter as Tony indicated earlier. Don Higgins [email protected]
