Avoid copying bitset that's subsequently cleared #15582
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In two instances, `FixedBitSet.ensureCapacity()` was called right before the bitset was cleared. This unnecessarily copied the internal array. This PR adds `FixedBitSet.ensureCapacityAndClear()` that avoids the copying. This should give a small performance improvement.
dweiss
approved these changes
Jan 16, 2026
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Author
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Should we backport this to 10.x? |
Contributor
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We can but it'd require moving the changes entry under 10x. |
dweiss
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Jan 19, 2026
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I've backported and updated changes.txt accordingly. |
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Author
Thanks, was just about to do it... |
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In two instances,
FixedBitSet.ensureCapacity()was called right before the bitset was cleared. This unnecessarily copied the internal array.This PR adds
FixedBitSet.ensureCapacityAndClear()that avoids the copying. This should give a small performance improvement.Also rename
numBitstodesiredBit- the argument didn't specify the number of bits we want to store, but the desired index we wanted to store at. This allowed for a much simpler javadoc that's not self-contradictory.