You are viewing a plain text version of this content. The canonical link for it is here.

Posted to jira@arrow.apache.org by "Frank Du (Jira)" <ji...@apache.org> on 2020/09/03 02:09:00 UTC

[jira] [Created] (ARROW-9904) [C++] Unroll the loop manually for CountSetBits

Frank Du created ARROW-9904:
-------------------------------

             Summary: [C++] Unroll the loop manually for CountSetBits
                 Key: ARROW-9904
                 URL: https://issues.apache.org/jira/browse/ARROW-9904
             Project: Apache Arrow
          Issue Type: Improvement
          Components: C++
            Reporter: Frank Du
            Assignee: Frank Du


The tight loop below can get better performance if unroll manually to indicate the compiler generating better parallel instructions.

for (auto iter = u64_data; iter < end; ++iter) {
 count += BitUtil::PopCount(*iter);
 }



--
This message was sent by Atlassian Jira
(v8.3.4#803005)