t...@gmplib.org (Torbjörn Granlund) writes: > Intel ark doesn't seem to know any processor called "U4100" so I cannot > figure out what generation it belongs to.
gmp's config.guess classifies it as core2. cat /proc/cpuinfo says processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 23 model name : Genuine Intel(R) CPU U4100 @ 1.30GHz I suspect there's a letter missing, and the marketing name really is "SU4100". It's likely since 2010, based on timestamps in my home directory. Anyway, *far* from the latest and greatest. > Again, if IIRC, small quotients may result in 16 cycle latency. That's > the lowest possible timing. In that case, not so surprising that the div1 function loses. Do other architectures also have decent performance for small-quotient division? Do you think table lookup on high bits should beat 16 cycles? It needs to give good enough accuracy (possibly with an adjustment step) to not result in a large penalty in iteration count. Even with div1 deleted, the code handles q == 1 specially, and only divides when q >= 2. Regards, /Niels -- Niels Möller. PGP-encrypted email is preferred. Keyid 368C6677. Internet email is subject to wholesale government surveillance. _______________________________________________ gmp-devel mailing list gmp-devel@gmplib.org https://gmplib.org/mailman/listinfo/gmp-devel
