Replace precomputed prime table with on-the-fly Miller-Rabin computation#802
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PointKernel wants to merge 5 commits intoNVIDIA:devfrom
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Replace precomputed prime table with on-the-fly Miller-Rabin computation#802PointKernel wants to merge 5 commits intoNVIDIA:devfrom
PointKernel wants to merge 5 commits intoNVIDIA:devfrom
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PointKernel
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type: improvement
sleeepyjack
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Apr 17, 2026
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Ha, a Miller-Rabin test in the wild! My old Discrete Math 101 professor would be proud of us :)
The diff in the prime.hpp is too large for the GH web UI to open. I inspected the file manually. One thing that caught my eye is that we use 128bit integers to prevent overflow. We have a macro check CUCO_HAS_INT128 that we should use in this case and have a fallback ready.
| if constexpr (cuco::is_double_hashing<probe>::value) { | ||
| return (CGSize == 1) ? 422 // 211 x 1 x 2 | ||
| : 412; // 103 x 2 x 2 | ||
| : 404; // 101 x 2 x 2 |
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why is this change needed?
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This PR replaces the precomputed prime table lookup with an on-the-fly calculation. While the new approach is slightly slower, it adds at most ~2 µs of overhead, making the performance impact negligible, and eliminates the need to store a large precomputed prime table.