implement Log10 and CmpUint64 (alternate version)
#136
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holiman
changed the title
Log10 and CmpUint64 (alternate version)
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From CI benchmark run #134 : This PR So this is on the order of 3-4x faster. |
Codecov Report
@@ Coverage Diff @@
## master #136 +/- ##
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Coverage 100.00% 100.00%
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Files 5 5
Lines 1628 1646 +18
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+ Hits 1628 1646 +18 |
holiman
commented
Mar 31, 2023
Merged
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Alternative to #134
This PR implements
Log10in what is probably close to the optimal way. Both PRs handle the majority of cases by one lookup based on the bitlength.For the remaining cases, #134 does 0, or, 1, or 2 divisions, and then a few uint64-compares and then it's done.
In this PR, for the remaining cases, we do an additional lookup, and then a comparison, and then we're done.
The drawback of this PR is that it has more precalculated 'persistent memory' hog.
So around 2 K. Not much, but still