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<p class="MsoNormal"><span style="mso-fareast-language:EN-US">Hi,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">I compared IRs and see what the issue is. I have not yet found which pass is responsible for this.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">The benchmark source:
<a href="http://www.llvm.org/viewvc/llvm-project/test-suite/trunk/MultiSource/Benchmarks/FreeBench/fourinarow/fourinarow.c?view=markup">
http://www.llvm.org/viewvc/llvm-project/test-suite/trunk/MultiSource/Benchmarks/FreeBench/fourinarow/fourinarow.c?view=markup</a><o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">The function of interest is ‘value’. There is a loop nest with small loops containing an if-statement. I see that the internal loops are fully unrolled. With the new pass manager, most of cmp+br
instructions are replaced with select instructions. This results huge basic blocks (400+ instructions). So we create a lot of instructions which are now executed unconditionally. According to the execution profile of the “good” program a lot of braches are
not taken. The “good” program has 1.01 Bn instructions executed. The “bad” program has 1.62 Bn instructions executed. Another problem is that a lot of the created instructions are FP instructions: SCVTF/FADD/FCVTZS. According to the Cortex-A57 optimization
guide they are quite heavy:<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">SCVTF: latency 10, throughput 1<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">FADD: latency 5, throughput 2<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">FCVTZS: latency 10, throughput 1<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">I think now it is clear why the regression is so huge.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">As soon as I identify the pass responsible for this I’ll create a bug report. Feel free to create it yourself if you know the pass. Just give a ticket number and I’ll add my results of analysis.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">Thanks,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US">Evgeny Astigeevich<o:p></o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:12.0pt;color:black">From: </span></b><span style="font-size:12.0pt;color:black">Sanjay Patel <spatel@rotateright.com><br>
<b>Date: </b>Wednesday, 25 October 2017 at 19:17<br>
<b>To: </b>Hal Finkel <hfinkel@anl.gov><br>
<b>Cc: </b>Evgeny Astigeevich <Evgeny.Astigeevich@arm.com>, Chandler Carruth <chandlerc@gmail.com>, llvm-dev <llvm-dev@lists.llvm.org>, nd <nd@arm.com><br>
<b>Subject: </b>Re: [llvm-dev] RFC: Switching to the new pass manager by default<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">The new PM always runs -latesimplifycfg rather than -simplifycfg. Test to show it:<o:p></o:p></p>
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<p class="MsoNormal"><a href="https://reviews.llvm.org/rL316351">https://reviews.llvm.org/rL316351</a><o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Given that these patches cited SPEC and test-suite perf while changing the behavior of simplifycfg:<br>
<a href="https://reviews.llvm.org/D30333" target="_blank">https://reviews.llvm.org/D30333</a><br>
<a href="https://reviews.llvm.org/D35411" target="_blank">https://reviews.llvm.org/D35411</a><o:p></o:p></p>
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<p class="MsoNormal"><br>
...the differences mentioned here might be related?<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt">Kindly request review so we can close this hole. :)<br>
<a href="https://reviews.llvm.org/D38631" target="_blank">https://reviews.llvm.org/D38631</a><o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On Wed, Oct 25, 2017 at 11:38 AM, Hal Finkel via llvm-dev <<a href="mailto:llvm-dev@lists.llvm.org" target="_blank">llvm-dev@lists.llvm.org</a>> wrote:<o:p></o:p></p>
<blockquote style="border:none;border-left:solid #CCCCCC 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-top:5.0pt;margin-right:0in;margin-bottom:5.0pt">
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<p><o:p> </o:p></p>
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<p class="MsoNormal">On 10/25/2017 12:32 PM, Evgeny Astigeevich wrote:<o:p></o:p></p>
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<blockquote style="margin-top:5.0pt;margin-bottom:5.0pt">
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Hi Hal,<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">I quickly checked the execution profile. It is real. The code changed significantly. A number of the hottest regions changed. I’ll compare IRs.<o:p></o:p></p>
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</blockquote>
<p class="MsoNormal"><br>
Thanks. Obviously a 1000% execution performance regression seems problematic.<br>
<br>
-Hal <o:p></o:p></p>
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<p class="MsoNormal"><br>
<br>
<br>
<o:p></o:p></p>
<blockquote style="margin-top:5.0pt;margin-bottom:5.0pt">
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">JFYI FreeBench/fourinarow time graph:
<a href="http://lnt.llvm.org/db_default/v4/nts/graph?highlight_run=76922&plot.1604615=1349.1604615.3" target="_blank">
http://lnt.llvm.org/db_default/v4/nts/graph?highlight_run=76922&plot.1604615=1349.1604615.3</a>
<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Its graph in our LNT is more stable.<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Thanks,<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Evgeny<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<div style="border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in">
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><b><span style="font-size:12.0pt;color:black">From:
</span></b><span style="font-size:12.0pt;color:black">Hal Finkel </span><a href="mailto:hfinkel@anl.gov" target="_blank"><span style="font-size:12.0pt"><hfinkel@anl.gov></span></a><span style="font-size:12.0pt;color:black"><br>
<b>Organization: </b>Argonne National Laboratory<br>
<b>Date: </b>Wednesday, 25 October 2017 at 18:14<br>
<b>To: </b>Evgeny Astigeevich </span><a href="mailto:Evgeny.Astigeevich@arm.com" target="_blank"><span style="font-size:12.0pt"><Evgeny.Astigeevich@arm.com></span></a><span style="font-size:12.0pt;color:black">, Chandler Carruth
</span><a href="mailto:chandlerc@gmail.com" target="_blank"><span style="font-size:12.0pt"><chandlerc@gmail.com></span></a><span style="font-size:12.0pt;color:black"><br>
<b>Cc: </b>llvm-dev </span><a href="mailto:llvm-dev@lists.llvm.org" target="_blank"><span style="font-size:12.0pt"><llvm-dev@lists.llvm.org></span></a><span style="font-size:12.0pt;color:black">, nd
</span><a href="mailto:nd@arm.com" target="_blank"><span style="font-size:12.0pt"><nd@arm.com></span></a><span style="font-size:12.0pt;color:black"><br>
<b>Subject: </b>Re: [llvm-dev] RFC: Switching to the new pass manager by default</span><o:p></o:p></p>
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<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p> <o:p></o:p></p>
<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">On 10/25/2017 12:10 PM, Evgeny Astigeevich via llvm-dev wrote:<o:p></o:p></p>
</div>
<blockquote style="margin-top:5.0pt;margin-bottom:5.0pt">
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Hi Chandler,<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">I ran the LNT benchmarks and SPEC2k6.train on AArch64 Cortex-A57. I used revisions: Clang 316561, LLVM 316563.<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Options: -O3 -mcpu=cortex-a57 -fomit-frame-pointer -fexperimental-new-pass-manager<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Regressions: execution time increase<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">LNT<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">MultiSource/Benchmarks/FreeBench/fourinarow/fourinarow 1018.58%<o:p></o:p></p>
</blockquote>
<p class="MsoNormal" style="mso-margin-top-alt:auto;margin-bottom:12.0pt"><br>
How real is this?<br>
<br>
-Hal<br>
<br>
<o:p></o:p></p>
<blockquote style="margin-top:5.0pt;margin-bottom:5.0pt">
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">MultiSource/Benchmarks/Fhourstones/fhourstones 9.06%<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">MultiSource/Benchmarks/Ptrdist/yacr2/yacr2 7.23%<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">MultiSource/Benchmarks/Olden/perimeter/perimeter 6.87%<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">MultiSource/Benchmarks/MiBench/consumer-typeset/consumer-typeset 6.02%<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">MultiSource/Benchmarks/Trimaran/enc-pc1/enc-pc1 5.59%<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">MultiSource/Benchmarks/ASC_Sequoia/AMGmk/AMGmk 5.03%<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">SPEC2k6<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">453.povray 17.11%<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">482.sphinx3 3.44%<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">444.namd 2.89%<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Improvements: execution time decrease<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">LNT<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">MultiSource/Benchmarks/BitBench/uudecode/uudecode -50.90%<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">SingleSource/Benchmarks/Adobe-C++/loop_unroll -27.75%<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">SingleSource/Benchmarks/Misc/perlin -21.35%<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">MultiSource/Benchmarks/Olden/em3d/em3d -19.12%<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">MultiSource/Benchmarks/tramp3d-v4/tramp3d-v4 -8.58%<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">SingleSource/Benchmarks/McGill/chomp -6.33%<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">MultiSource/Benchmarks/sim/sim -5.41%<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">MultiSource/Applications/ClamAV/clamscan -3.11%<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">MultiSource/Benchmarks/TSVC/Symbolics-dbl/Symbolics-dbl -2.81%<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">SPEC2k6<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">429.mcf -5.18%<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">473.astar -2.65%<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">400.perlbench -1.90%<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">There are also code sizes increases/decreases. The maximum increase is 18.98%. The maximum decrease is 25.65%.<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Thanks,<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Evgeny Astigeevich<o:p></o:p></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><b><span style="font-size:12.0pt;color:black">From:
</span></b><span style="font-size:12.0pt;color:black">llvm-dev </span><a href="mailto:llvm-dev-bounces@lists.llvm.org" target="_blank"><span style="font-size:12.0pt"><llvm-dev-bounces@lists.llvm.org></span></a><span style="font-size:12.0pt;color:black"> on
behalf of Chandler Carruth via llvm-dev </span><a href="mailto:llvm-dev@lists.llvm.org" target="_blank"><span style="font-size:12.0pt"><llvm-dev@lists.llvm.org></span></a><span style="font-size:12.0pt;color:black"><br>
<b>Reply-To: </b>Chandler Carruth </span><a href="mailto:chandlerc@gmail.com" target="_blank"><span style="font-size:12.0pt"><chandlerc@gmail.com></span></a><span style="font-size:12.0pt;color:black"><br>
<b>Date: </b>Wednesday, 18 October 2017 at 07:51<br>
<b>To: </b>llvm-dev </span><a href="mailto:llvm-dev@lists.llvm.org" target="_blank"><span style="font-size:12.0pt"><llvm-dev@lists.llvm.org></span></a><span style="font-size:12.0pt;color:black"><br>
<b>Subject: </b>[llvm-dev] RFC: Switching to the new pass manager by default</span><o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Greetings everyone!
<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">The new pass manager is getting extremely close to the point where I'm not aware of any significant outstanding work needed, and I'd like to see what else would be needed to enable
it by default. Here are the current functionality I'm aware of outstanding:<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<div>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">1) Does not do non-trivial loop unswitching. Majority of this is in
<a href="https://reviews.llvm.org/D34200" target="_blank">https://reviews.llvm.org/D34200</a> but will need one or two small follow-ups.<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">2) Currently, sanitizers don't work correctly with it. Thanks to the work of others, the missing infrastructure has been added and I'll send a patch to wire this up this week.<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">3) Missing support for 'optnone'. I've been working on this, but the existing testing wasn't as thorough as I wanted, so it is going slowly. I've got about 1/4 of this implemented
and should have patches this week or next.<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">4) Missing opt-bisect (or similar) facility. This looks pretty trivial to add, but I've not even started. If anyone is interested in it, go for it. We might even be able to do something
simpler using the generic debug counters and get equivalent functionality.<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">... that's it?<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Optimization quality / run-time performance:<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">- We've been using it at Google extensively and are very happy with the optimization quality. Benchmarks look *very* good here.<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">- More data from other users would be important.<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">- You can try it out with `-fexperimental-new-pass-manager` to Clang<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Compile-time performance:<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">- Sometimes *much* better due to cached analyses.<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">- Sometimes worse, typically due to more / different inlining in turn running main pipeline (GVN + InstCombine) more times or over more code.<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">- Overall somewhat a wash, but the increased compile times typically due to the optimizer "trying" harder, so not too concerning on our end.<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">- Again, more feedback from other users good: `-fexperimental-new-pass-manager` to Clang<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Once the four missing things land, I'll also happily work on collecting some of the basics on the test-suite and CTMark. But I suspect more "in the wild" data would really be useful
here given the significance of the change.<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Thoughts? What else (beyond the four items above and feedback on run-time and compile-time) would folks like to see?<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Once this happens, I'll also be preparing some batch, mechanical updates to the test suite to primarily use the new pass manager. Also there is lots of documentation updates that
will be needed here.<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">-Chandler<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"> <o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">PS: I'll be sending a note to cfe-dev as a "heads up" about this discussion as in some ways, the default flip is mostly a Clang default flip. But hopefully our doc updates will
trigger this being "perceived" as the default for other frontends, and I'll try to reach out to other major frontends as well (Swift and Rust are on my radar, and I've already started talking with Philip Reames about their Falcon JIT).<o:p></o:p></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;margin-bottom:12.0pt"><br>
<br>
<o:p></o:p></p>
<pre>_______________________________________________<o:p></o:p></pre>
<pre>LLVM Developers mailing list<o:p></o:p></pre>
<pre><a href="mailto:llvm-dev@lists.llvm.org" target="_blank">llvm-dev@lists.llvm.org</a><o:p></o:p></pre>
<pre><a href="http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev" target="_blank">http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev</a><o:p></o:p></pre>
</blockquote>
<p class="MsoNormal" style="mso-margin-top-alt:auto;margin-bottom:12.0pt"><o:p> </o:p></p>
<pre>-- <o:p></o:p></pre>
<pre>Hal Finkel<o:p></o:p></pre>
<pre>Lead, Compiler Technology and Programming Languages<o:p></o:p></pre>
<pre>Leadership Computing Facility<o:p></o:p></pre>
<pre>Argonne National Laboratory<o:p></o:p></pre>
</div>
</blockquote>
<p class="MsoNormal"><br>
<br>
<o:p></o:p></p>
<pre>-- <o:p></o:p></pre>
<pre>Hal Finkel<o:p></o:p></pre>
<pre>Lead, Compiler Technology and Programming Languages<o:p></o:p></pre>
<pre>Leadership Computing Facility<o:p></o:p></pre>
<pre>Argonne National Laboratory<o:p></o:p></pre>
</div>
</div>
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<p class="MsoNormal" style="margin-bottom:12.0pt"><br>
_______________________________________________<br>
LLVM Developers mailing list<br>
<a href="mailto:llvm-dev@lists.llvm.org">llvm-dev@lists.llvm.org</a><br>
<a href="http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev" target="_blank">http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev</a><o:p></o:p></p>
</blockquote>
</div>
<p class="MsoNormal"><span style="mso-fareast-language:EN-US"><o:p> </o:p></span></p>
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