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https://issues.apache.org/jira/browse/LUCENE-5856?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14080165#comment-14080165
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ASF subversion and git services commented on LUCENE-5856:
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Commit 1614790 from [~rcmuir] in branch 'dev/branches/branch_4x'
[ https://svn.apache.org/r1614790 ]
LUCENE-5856: Optimize Fixed/Open/LongBitSet to remove unnecessary AND
> remove useless & 0x3f from *BitSet.get and company
> --------------------------------------------------
>
> Key: LUCENE-5856
> URL: https://issues.apache.org/jira/browse/LUCENE-5856
> Project: Lucene - Core
> Issue Type: Improvement
> Reporter: Robert Muir
> Fix For: 5.0, 4.10
>
> Attachments: LUCENE-5856.patch
>
>
> java specification says:
> {quote}
> If the promoted type of the left-hand operand is long, then only the six
> lowest-order bits of the right-hand operand are used as the shift distance.
> It is as if the right-hand operand were subjected to a bitwise logical AND
> operator & (ยง15.22.1) with the mask value 0x3f (0b111111). The shift distance
> actually used is therefore always in the range 0 to 63, inclusive.
> {quote}
> and x86 works the same way.
> if we remove this, we just see less instructions with printassembly...
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