Opt: Generalize the RuntimeLong.toString optimization to any base.
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gzm0
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Jun 8, 2025
| * It holds that 2^30 >= radixPowLength >= 2^30 / 36 > 2^24. | ||
| * | ||
| * Therefore, (2^64 - 1) / radixPowLength < 2^(64-24) = 2^40, which | ||
| * confortably fits in a `Double`. `toUnsignedStringLarge` relies on that |
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| * confortably fits in a `Double`. `toUnsignedStringLarge` relies on that | |
| * comfortably fits in a `Double`. `toUnsignedStringLarge` relies on that |
| * - chunkLength is then log_radix(radixPowLength). | ||
| * - paddingZeros is a string with exactly chunkLength '0's. | ||
| * - overflowBarrier is divideUnsigned(-1L, radixPowLength) so that we | ||
| * can test whether someValue * radixPowLength will overflow. | ||
| * | ||
| * It holds that 2^30 >= radixPowLength >= 2^30 / 36 > 2^24. |
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| * It holds that 2^30 >= radixPowLength >= 2^30 / 36 > 2^24. | |
| * It holds that 2^30 >= radixPowLength > 2^30 / maxRadix = 2^30 / 36 > 2^24. |
With some more care to the choice of divisors (`radixPowLength`)
we use in `jl.Long.to{,Unsigned}String`, we can generalize the
optimization of `RuntimeLong.toString` to all the possible bases.
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With some more care to the choice of divisors (
radixPowLength) we use injl.Long.to{,Unsigned}String, we can generalize the optimization ofRuntimeLong.toStringto all the possible bases.