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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Hi Xin,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Exactly what I meant, thank you for quick revert.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="RU" style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Thank you,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D">Serguei.<o:p></o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> Xin Tong [mailto:trent.xin.tong@gmail.com]
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<b>Sent:</b> Friday, October 6, 2017 6:36 AM<br>
<b>To:</b> reviews+D38563+public+d275dea540a39693@reviews.llvm.org<br>
<b>Cc:</b> David Li <davidxl@google.com>; Dehao Chen <danielcdh@gmail.com>; kyle+llvm@iteratee.net; Chandler Carruth <chandlerc@gmail.com>; Serguei Katkov <serguei.katkov@azul.com>; llvm-commits <llvm-commits@lists.llvm.org><br>
<b>Subject:</b> Re: [PATCH] D38563: [MachineBlockPlacement] Make sure PreferredLoopExit is cleared everytime new loop is processed<o:p></o:p></span></p>
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<p class="MsoNormal">On Fri, Oct 6, 2017 at 2:56 AM, Serguei Katkov via Phabricator <<a href="mailto:reviews@reviews.llvm.org" target="_blank">reviews@reviews.llvm.org</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal">skatkov added a comment.<br>
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I believe that added assert is invalid. PreferredLoopExit might be easily part of the loop L if it was not added to hot chain. In other words pass decided to layout this BB in a scope of outer loop or function at all.<br>
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If you agree with me, please fix this asap.<o:p></o:p></p>
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<p class="MsoNormal">Hi Serguei<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">I think i know what you mean. The problem is the block may be excluded from the LoopBlockSet (because its cold), and its predecessor in the current loop is chosen as the ExitingBlock to rotate with. However, its predecessor does not exit
the current loop. Am I correct ?<o:p></o:p></p>
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<p class="MsoNormal">I reverted that assert so unbreak a reported build. I will add a test case once we are on the same page with this.<o:p></o:p></p>
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<p class="MsoNormal">Thanks!<o:p></o:p></p>
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<p class="MsoNormal">-Xin <o:p></o:p></p>
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Repository:<br>
rL LLVM<br>
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<a href="https://reviews.llvm.org/D38563" target="_blank">https://reviews.llvm.org/D38563</a><br>
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<p class="MsoNormal">-- <o:p></o:p></p>
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<p class="MsoNormal">Software Engineer - Compiler Toolchain<br>
Employee of Facebook Inc.<o:p></o:p></p>
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