Chengxiang Li created HIVE-10180:
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             Summary: Loop optimization in ColumnArithmeticColumn.txt
                 Key: HIVE-10180
                 URL: https://issues.apache.org/jira/browse/HIVE-10180
             Project: Hive
          Issue Type: Sub-task
            Reporter: Chengxiang Li
            Assignee: Chengxiang Li
            Priority: Minor


JVM is quite strict on the code schema which may executed with SIMD 
instructions, take a loop in DoubleColAddDoubleColumn.java for example, 
{code:java}
for (int i = 0; i != n; i++) {
  outputVector[i] = vector1[0] + vector2[i];
}
{code}
The "vector1[0]" reference would prevent JVM to execute this part of code with 
vectorized instructions, we need to assign the "vector1[0]" to a variable 
outside of loop, and use that variable in loop.



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