[Impala-ASF-CR] Experiment: glibc strncmp/memcmp appears much faster than SSE4.2

["Dan Hecht (Code Review)" <ge...@cloudera.org>]

Dan Hecht has posted comments on this change.

Change subject: Experiment: glibc strncmp/memcmp appears much faster than SSE4.2
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Patch Set 1:

(1 comment)

http://gerrit.cloudera.org:8080/#/c/6768/1//COMMIT_MSG
Commit Message:

PS1, Line 17: memcmp is sse4.1-based
does it fall back to non-SSE4.1, if the CPU doesn't have SSE4.1? (maybe using IFUNC)?

If so, then I think it makes sense to switch to gcc's version if it's always faster. You'll probably want to check codegen case too (make sure the cpu dependent dispatch all works with clang too).


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Gerrit-MessageType: comment
Gerrit-Change-Id: Ie4786a4a75fdaffedd6e17cf076b5368ba4b4e3e
Gerrit-PatchSet: 1
Gerrit-Project: Impala-ASF
Gerrit-Branch: master
Gerrit-Owner: Jim Apple <jb...@apache.org>
Gerrit-Reviewer: Dan Hecht <dh...@cloudera.com>
Gerrit-Reviewer: Jim Apple <jb...@apache.org>
Gerrit-Reviewer: Mostafa Mokhtar <mm...@cloudera.com>
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