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https://issues.apache.org/jira/browse/ARROW-3055?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16696140#comment-16696140
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Wes McKinney commented on ARROW-3055:
-------------------------------------
I experimented with this a bit at one point. The idea was that when a byte is
{{0xFF}} or {{0x0}} that you could return true/false always in
{{IsSet/IsNotSet}}. So the implementation of {{IsSet}} would become
{code}
bool IsSet() const { return byte_all_set_ || (current_byte_ & (1 <<
bit_offset_)) != 0; }
{code}
It seems that the additional labor of determining {{byte_all_set_}} negates any
performance gains, but it would be worthwhile to determine for certain
> [C++] Use byte pop counts to bypass bit checking in some cases in
> BitmapReader classes
> --------------------------------------------------------------------------------------
>
> Key: ARROW-3055
> URL: https://issues.apache.org/jira/browse/ARROW-3055
> Project: Apache Arrow
> Issue Type: Improvement
> Components: C++
> Reporter: Wes McKinney
> Priority: Major
>
> When performing a scan of a bitmap, skipping bit checking math could improve
> performance, but we would need to investigate
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