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<p class="MsoNormal" style="margin-left:.5in"><b>From:</b> Wei Mi <wmi@google.com>
<br>
<b>Sent:</b> Friday, July 26, 2019 11:54 AM<br>
<b>To:</b> reviews+D65310+public+218d41e11489d8c7@reviews.llvm.org<br>
<b>Cc:</b> David Li <davidxl@google.com>; Eli Friedman <efriedma@quicinc.com>; brzycki@gmail.com; simachijun@gmail.com; hiraditya@msn.com; jfbastien@apple.com; llvm-commits <llvm-commits@lists.llvm.org>; jun.l@samsung.com; florian_hahn@apple.com; czhengsz@cn.ibm.com<br>
<b>Subject:</b> [EXT] Re: [PATCH] D65310: [JumpThreading] In updatePredecessorProfileMetadata, stop searching predecessor when the current bb is an unreachable single bb loop<o:p></o:p></p>
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<p class="MsoNormal" style="margin-left:.5in">On Fri, Jul 26, 2019 at 11:34 AM Eli Friedman via Phabricator <<a href="mailto:reviews@reviews.llvm.org">reviews@reviews.llvm.org</a>> wrote:<o:p></o:p></p>
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Calling getDomTree() here is expensive; it flushes all updates in the DomTreeUpdater.<o:p></o:p></p>
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<p class="MsoNormal" style="margin-left:.5in">Or I can detect loop using a set keeping nodes which have been visited. Whenever SinglePredBB is seen in the set, stop searching. <o:p></o:p></p>
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<p class="MsoNormal">That’s fine.<o:p></o:p></p>
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<p class="MsoNormal">-Eli<o:p></o:p></p>
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