impala-reviews mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Zach Amsden (Code Review)" <>
Subject [Impala-ASF-CR] IMPALA-5266 Impala ABM / LZCNT support
Date Thu, 04 May 2017 21:26:47 GMT
Zach Amsden has uploaded a new patch set (#7).

Change subject: IMPALA-5266 Impala ABM / LZCNT support

IMPALA-5266 Impala ABM / LZCNT support

I recently added some code that wants to do upwards power of 2
calculation.  Turns out this can be done much more quickly in
hardware.  It isn't on a perf critical code path yet but
still seems like a decent idea.

PopcountNoHw was absolutely atrocious as it contains a totally
unpredictable loop that can be computed much more efficiently,
so I fixed that as well.

Testing: Added a perf test to verify this is faster (it is)
and updated the bit-util-test to add better test coverage.

Change-Id: I9f6a465ab4a9ee4f582847f8e211a779bdede3d2
M be/src/benchmarks/CMakeLists.txt
A be/src/benchmarks/
M be/src/codegen/CMakeLists.txt
M be/src/exprs/
M be/src/exprs/
M be/src/util/
M be/src/util/bit-util.h
M be/src/util/
M be/src/util/cpu-info.h
M be/src/util/fixed-size-hash-table.h
M be/src/util/sse-util.h
11 files changed, 377 insertions(+), 48 deletions(-)

  git pull ssh:// refs/changes/21/5821/7
To view, visit
To unsubscribe, visit

Gerrit-MessageType: newpatchset
Gerrit-Change-Id: I9f6a465ab4a9ee4f582847f8e211a779bdede3d2
Gerrit-PatchSet: 7
Gerrit-Project: Impala-ASF
Gerrit-Branch: master
Gerrit-Owner: Zach Amsden <>
Gerrit-Reviewer: Attila Jeges <>
Gerrit-Reviewer: Dan Hecht <>
Gerrit-Reviewer: Jim Apple <>
Gerrit-Reviewer: Marcel Kornacker <>
Gerrit-Reviewer: Tim Armstrong <>
Gerrit-Reviewer: Zach Amsden <>

View raw message