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Re: [PATCH v2.1] Use long for mantissa for generic mp code
On 2013-03-14 01:28, Siddhesh Poyarekar wrote:
Using bit shifts instead of division makes (as expected) a neat
positive difference to performance of pow of about 5%. I've also made
the comment for INTEGER_OF more verbose.
For the record, this seems to have sped up the benchmarks
by a factor of 10-20 on arm:
exp: ITERS:100000: TOTAL:19.2022s, MAX:266889ns, MIN:190590ns, 5207.73 iter/s
pow: ITERS:100000: TOTAL:47.5425s, MAX:482874ns, MIN:474051ns, 2103.38 iter/s
exp: ITERS:100000: TOTAL:2.6179s, MAX:26460.7ns, MIN:26068.7ns, 38198.5 iter/s
pow: ITERS:100000: TOTAL:2.1143s, MAX:21386.5ns, MIN:21019.5ns, 47296.9 iter/s
which looks fantastic, except the pow test running faster than the exp test,
which seems implausible.
Did you say something about unused outputs in the benchmark between v2 and
v2.1? Did you check in the wrong version?