Prototype for Probably Correct: Oscar issue 3110

[JohnAAbbott]

Prototype implementation incorporating some feedback.
To work this PR needs the code from the draft PR Nemocas/AbstractAlgebra.jl#2395

[thofma]

What is the overhead of this? How much more expensive is next_prime(ZZ(2))?

[JohnAAbbott]

What is the overhead of this? How much more expensive is next_prime(ZZ(2))?

No idea! If you're calling next_prime(n) where n is ZZ(2) then you are already throwing away some performance compared to when n is Int64(2). I tried measuring the difference, and obtained a factor of 20, but there was over 60% GC time. Anyway, if dodgy mode is off then the overhead should be quite low.

I add that next_prime(::Int) is unchanged. Not sure how often one calls next_prime for value which do not fit into Int64.

[thofma]

Yes, my question was about the additional overhead when calling next_prime(ZZ(2)) with dodgy mode off.

[JohnAAbbott]

Yes, my question was about the additional overhead when calling next_prime(ZZ(2)) with dodgy mode off.

I did not observe any significant detrimental effect.