llvm warning: build with -O3 so that clang can unroll the loop

[smuzaffar]

PR description:

With LLVM 9 we have start seeing the warnings [a]. Looks like with -O3 clang is able to unroll the loop.

FYI, @VinInn

[a]

DataFormats/Math/test/CholeskyInvert_t.cpp:48:6: warning: loop not vectorized: the optimizer was unable to perform the requested transformation; the transformation might be disabled or specified as part of an unsupported transformation ordering [-Wpass-failed=transform-warning]
 void go(bool soa) {

PR validation:

Local build for both CLANG and normal IBs look good

[cmsbuild]

The code-checks are being triggered in jenkins.

[cmsbuild]

+code-checks

Logs: https://cmssdt.cern.ch/SDT/code-checks/cms-sw-PR-29790/15253

• This PR adds an extra 16KB to repository

[smuzaffar]

please test

[cmsbuild]

A new Pull Request was created by @smuzaffar (Malik Shahzad Muzaffar) for master.

It involves the following packages:

DataFormats/Math

@perrotta, @cmsbuild, @slava77 can you please review it and eventually sign? Thanks.
@makortel, @felicepantaleo, @fabiocos, @rovere this is something you requested to watch as well.
@silviodonato, @dpiparo you are the release manager for this.

cms-bot commands are listed here

[cmsbuild]

The tests are being triggered in jenkins.
https://cmssdt.cern.ch/jenkins/job/ib-run-pr-tests/6199/console Started: 2020/05/09 13:39

[cmsbuild]

+1
Tested at: 14a775a
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-b448dc/6199/summary.html
CMSSW: CMSSW_11_1_X_2020-05-08-2300
SCRAM_ARCH: slc7_amd64_gcc820

[cmsbuild]

Comparison job queued.

[cmsbuild]

Comparison is ready
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-b448dc/6199/summary.html

Comparison Summary:

• No significant changes to the logs found
• Reco comparison results: 4 differences found in the comparisons
• DQMHistoTests: Total files compared: 34
• DQMHistoTests: Total histograms compared: 2697527
• DQMHistoTests: Total failures: 71
• DQMHistoTests: Total nulls: 0
• DQMHistoTests: Total successes: 2697137
• DQMHistoTests: Total skipped: 319
• DQMHistoTests: Total Missing objects: 0
• DQMHistoSizes: Histogram memory added: 0.0 KiB( 33 files compared)
• Checked 147 log files, 16 edm output root files, 34 DQM output files

[slava77]

+1

for #29790 14a775a

• technical; as described

[cmsbuild]

This pull request is fully signed and it will be integrated in one of the next master IBs (tests are also fine). This pull request will now be reviewed by the release team before it's merged. @silviodonato, @dpiparo (and backports should be raised in the release meeting by the corresponding L2)

[silviodonato]

+1